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-rw-r--r--src/grp-resolve/systemd-resolved/.gitignore6
-rw-r--r--src/grp-resolve/systemd-resolved/Makefile141
-rw-r--r--src/grp-resolve/systemd-resolved/RFCs59
-rw-r--r--src/grp-resolve/systemd-resolved/dnssec-trust-anchors.d.xml200
-rw-r--r--src/grp-resolve/systemd-resolved/org.freedesktop.resolve1.conf27
-rw-r--r--src/grp-resolve/systemd-resolved/org.freedesktop.resolve1.service12
-rw-r--r--src/grp-resolve/systemd-resolved/resolv.conf11
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-bus.c1690
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-bus.h25
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-conf.c241
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-conf.h36
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-cache.c1065
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-cache.h52
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-query.c1122
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-query.h141
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-scope.c1038
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-scope.h111
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-search-domain.c228
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-search-domain.h74
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-server.c778
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-server.h147
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-stream.c421
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-stream.h80
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-stub.c573
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-stub.h31
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-synthesize.c414
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-synthesize.h31
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-transaction.c3108
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-transaction.h180
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-trust-anchor.c744
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-trust-anchor.h43
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-zone.c665
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-dns-zone.h82
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-etc-hosts.c449
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-etc-hosts.h29
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-gperf.gperf24
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-link-bus.c630
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-link-bus.h38
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-link.c1115
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-link.h118
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-llmnr.c472
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-llmnr.h32
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-manager.c1379
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-manager.h183
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-mdns.c288
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-mdns.h30
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-resolv-conf.c267
-rw-r--r--src/grp-resolve/systemd-resolved/resolved-resolv-conf.h27
-rw-r--r--src/grp-resolve/systemd-resolved/resolved.c121
-rw-r--r--src/grp-resolve/systemd-resolved/resolved.conf.in20
-rw-r--r--src/grp-resolve/systemd-resolved/resolved.conf.xml230
-rw-r--r--src/grp-resolve/systemd-resolved/systemd-resolved.service.m4.in34
-rw-r--r--src/grp-resolve/systemd-resolved/systemd-resolved.service.xml234
-rw-r--r--src/grp-resolve/systemd-resolved/systemd-resolved.sysusers8
-rw-r--r--src/grp-resolve/systemd-resolved/systemd-resolved.tmpfiles10
55 files changed, 19314 insertions, 0 deletions
diff --git a/src/grp-resolve/systemd-resolved/.gitignore b/src/grp-resolve/systemd-resolved/.gitignore
new file mode 100644
index 0000000000..f0835923b7
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/.gitignore
@@ -0,0 +1,6 @@
+/resolved-gperf.c
+/resolved.conf
+/dns_type-from-name.gperf
+/dns_type-from-name.h
+/dns_type-list.txt
+/dns_type-to-name.h
diff --git a/src/grp-resolve/systemd-resolved/Makefile b/src/grp-resolve/systemd-resolved/Makefile
new file mode 100644
index 0000000000..78b352b76f
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/Makefile
@@ -0,0 +1,141 @@
+# -*- Mode: makefile; indent-tabs-mode: t -*-
+#
+# This file is part of systemd.
+#
+# Copyright 2010-2012 Lennart Poettering
+# Copyright 2010-2012 Kay Sievers
+# Copyright 2013 Zbigniew Jędrzejewski-Szmek
+# Copyright 2013 David Strauss
+# Copyright 2016 Luke Shumaker
+#
+# systemd is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation; either version 2.1 of the License, or
+# (at your option) any later version.
+#
+# systemd is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with systemd; If not, see <http://www.gnu.org/licenses/>.
+include $(dir $(lastword $(MAKEFILE_LIST)))/../../../config.mk
+include $(topsrcdir)/build-aux/Makefile.head.mk
+
+ifneq ($(ENABLE_RESOLVED),)
+
+basic_dns_sources = \
+ src/resolve/resolved-dns-dnssec.c \
+ src/resolve/resolved-dns-dnssec.h \
+ src/resolve/resolved-dns-packet.c \
+ src/resolve/resolved-dns-packet.h \
+ src/resolve/resolved-dns-rr.c \
+ src/resolve/resolved-dns-rr.h \
+ src/resolve/resolved-dns-answer.c \
+ src/resolve/resolved-dns-answer.h \
+ src/resolve/resolved-dns-question.c \
+ src/resolve/resolved-dns-question.h \
+ src/resolve/dns-type.c \
+ src/resolve/dns-type.h
+
+systemd_resolved_SOURCES = \
+ src/resolve/resolved.c \
+ src/resolve/resolved-manager.c \
+ src/resolve/resolved-manager.h \
+ src/resolve/resolved-conf.c \
+ src/resolve/resolved-conf.h \
+ src/resolve/resolved-resolv-conf.c \
+ src/resolve/resolved-resolv-conf.h \
+ src/resolve/resolved-bus.c \
+ src/resolve/resolved-bus.h \
+ src/resolve/resolved-link.h \
+ src/resolve/resolved-link.c \
+ src/resolve/resolved-link-bus.c \
+ src/resolve/resolved-link-bus.h \
+ src/resolve/resolved-llmnr.h \
+ src/resolve/resolved-llmnr.c \
+ src/resolve/resolved-mdns.h \
+ src/resolve/resolved-mdns.c \
+ src/resolve/resolved-def.h \
+ $(basic_dns_sources) \
+ src/resolve/resolved-dns-query.h \
+ src/resolve/resolved-dns-query.c \
+ src/resolve/resolved-dns-synthesize.h \
+ src/resolve/resolved-dns-synthesize.c \
+ src/resolve/resolved-dns-transaction.h \
+ src/resolve/resolved-dns-transaction.c \
+ src/resolve/resolved-dns-scope.h \
+ src/resolve/resolved-dns-scope.c \
+ src/resolve/resolved-dns-server.h \
+ src/resolve/resolved-dns-server.c \
+ src/resolve/resolved-dns-search-domain.h \
+ src/resolve/resolved-dns-search-domain.c \
+ src/resolve/resolved-dns-cache.h \
+ src/resolve/resolved-dns-cache.c \
+ src/resolve/resolved-dns-zone.h \
+ src/resolve/resolved-dns-zone.c \
+ src/resolve/resolved-dns-stream.h \
+ src/resolve/resolved-dns-stream.c \
+ src/resolve/resolved-dns-trust-anchor.h \
+ src/resolve/resolved-dns-trust-anchor.c \
+ src/resolve/resolved-dns-stub.h \
+ src/resolve/resolved-dns-stub.c \
+ src/resolve/resolved-etc-hosts.h \
+ src/resolve/resolved-etc-hosts.c \
+ src/shared/gcrypt-util.c \
+ src/shared/gcrypt-util.h
+
+nodist_systemd_resolved_SOURCES = \
+ src/resolve/dns_type-from-name.h \
+ src/resolve/dns_type-to-name.h \
+ src/resolve/resolved-gperf.c
+
+systemd_resolved_CFLAGS = \
+ $(GCRYPT_CFLAGS)
+
+systemd_resolved_LDADD = \
+ libsystemd-network.la \
+ libsystemd-shared.la \
+ $(GCRYPT_LIBS) \
+ -lm
+
+rootlibexec_PROGRAMS += \
+ systemd-resolved
+
+nodist_systemunit_DATA += \
+ units/systemd-resolved.service
+
+dist_systemunit_DATA_busnames += \
+ units/org.freedesktop.resolve1.busname
+
+dist_dbuspolicy_DATA += \
+ src/resolve/org.freedesktop.resolve1.conf
+
+dist_dbussystemservice_DATA += \
+ src/resolve/org.freedesktop.resolve1.service
+
+SYSTEM_UNIT_ALIASES += \
+ systemd-resolved.service dbus-org.freedesktop.resolve1.service
+
+BUSNAMES_TARGET_WANTS += \
+ org.freedesktop.resolve1.busname
+
+GENERAL_ALIASES += \
+ $(systemunitdir)/systemd-resolved.service $(pkgsysconfdir)/system/multi-user.target.wants/systemd-resolved.service
+
+nodist_pkgsysconf_DATA += \
+ src/resolve/resolved.conf
+
+endif # ENABLE_RESOLVED
+gperf_gperf_sources += \
+ src/resolve/resolved-gperf.gperf
+
+EXTRA_DIST += \
+ units/systemd-resolved.service.m4.in \
+ src/resolve/resolved.conf.in
+
+dist_rootlibexec_DATA += \
+ src/resolve/resolv.conf
+
+include $(topsrcdir)/build-aux/Makefile.tail.mk
diff --git a/src/grp-resolve/systemd-resolved/RFCs b/src/grp-resolve/systemd-resolved/RFCs
new file mode 100644
index 0000000000..09c85f9518
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/RFCs
@@ -0,0 +1,59 @@
+Y = Comprehensively Implemented, to the point appropriate for resolved
+D = Comprehensively Implemented, by a dependency of resolved
+! = Missing and something we might want to implement
+~ = Needs no explicit support or doesn't apply
+? = Is this relevant today?
+ = We are working on this
+
+Y https://tools.ietf.org/html/rfc1034 → DOMAIN NAMES - CONCEPTS AND FACILITIES
+Y https://tools.ietf.org/html/rfc1035 → DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATION
+? https://tools.ietf.org/html/rfc1101 → DNS Encoding of Network Names and Other Types
+Y https://tools.ietf.org/html/rfc1123 → Requirements for Internet Hosts — Application and Support
+~ https://tools.ietf.org/html/rfc1464 → Using the Domain Name System To Store Arbitrary String Attributes
+Y https://tools.ietf.org/html/rfc1536 → Common DNS Implementation Errors and Suggested Fixes
+Y https://tools.ietf.org/html/rfc1876 → A Means for Expressing Location Information in the Domain Name System
+Y https://tools.ietf.org/html/rfc2181 → Clarifications to the DNS Specification
+Y https://tools.ietf.org/html/rfc2308 → Negative Caching of DNS Queries (DNS NCACHE)
+Y https://tools.ietf.org/html/rfc2782 → A DNS RR for specifying the location of services (DNS SRV)
+D https://tools.ietf.org/html/rfc3492 → Punycode: A Bootstring encoding of Unicode for Internationalized Domain Names in Applications (IDNA)
+Y https://tools.ietf.org/html/rfc3596 → DNS Extensions to Support IP Version 6
+Y https://tools.ietf.org/html/rfc3597 → Handling of Unknown DNS Resource Record (RR) Types
+Y https://tools.ietf.org/html/rfc4033 → DNS Security Introduction and Requirements
+Y https://tools.ietf.org/html/rfc4034 → Resource Records for the DNS Security Extensions
+Y https://tools.ietf.org/html/rfc4035 → Protocol Modifications for the DNS Security Extensions
+! https://tools.ietf.org/html/rfc4183 → A Suggested Scheme for DNS Resolution of Networks and Gateways
+Y https://tools.ietf.org/html/rfc4255 → Using DNS to Securely Publish Secure Shell (SSH) Key Fingerprints
+Y https://tools.ietf.org/html/rfc4343 → Domain Name System (DNS) Case Insensitivity Clarification
+~ https://tools.ietf.org/html/rfc4470 → Minimally Covering NSEC Records and DNSSEC On-line Signing
+Y https://tools.ietf.org/html/rfc4501 → Domain Name System Uniform Resource Identifiers
+Y https://tools.ietf.org/html/rfc4509 → Use of SHA-256 in DNSSEC Delegation Signer (DS) Resource Records (RRs)
+~ https://tools.ietf.org/html/rfc4592 → The Role of Wildcards in the Domain Name System
+~ https://tools.ietf.org/html/rfc4697 → Observed DNS Resolution Misbehavior
+Y https://tools.ietf.org/html/rfc4795 → Link-Local Multicast Name Resolution (LLMNR)
+Y https://tools.ietf.org/html/rfc5011 → Automated Updates of DNS Security (DNSSEC) Trust Anchors
+Y https://tools.ietf.org/html/rfc5155 → DNS Security (DNSSEC) Hashed Authenticated Denial of Existence
+Y https://tools.ietf.org/html/rfc5452 → Measures for Making DNS More Resilient against Forged Answers
+Y https://tools.ietf.org/html/rfc5702 → Use of SHA-2 Algorithms with RSA in DNSKEY and RRSIG Resource Records for DNSSEC
+Y https://tools.ietf.org/html/rfc5890 → Internationalized Domain Names for Applications (IDNA): Definitions and Document Framework
+Y https://tools.ietf.org/html/rfc5891 → Internationalized Domain Names in Applications (IDNA): Protocol
+Y https://tools.ietf.org/html/rfc5966 → DNS Transport over TCP - Implementation Requirements
+Y https://tools.ietf.org/html/rfc6303 → Locally Served DNS Zones
+Y https://tools.ietf.org/html/rfc6604 → xNAME RCODE and Status Bits Clarification
+Y https://tools.ietf.org/html/rfc6605 → Elliptic Curve Digital Signature Algorithm (DSA) for DNSSEC
+ https://tools.ietf.org/html/rfc6672 → DNAME Redirection in the DNS
+! https://tools.ietf.org/html/rfc6731 → Improved Recursive DNS Server Selection for Multi-Interfaced Nodes
+Y https://tools.ietf.org/html/rfc6761 → Special-Use Domain Names
+ https://tools.ietf.org/html/rfc6762 → Multicast DNS
+ https://tools.ietf.org/html/rfc6763 → DNS-Based Service Discovery
+~ https://tools.ietf.org/html/rfc6781 → DNSSEC Operational Practices, Version 2
+Y https://tools.ietf.org/html/rfc6840 → Clarifications and Implementation Notes for DNS Security (DNSSEC)
+Y https://tools.ietf.org/html/rfc6891 → Extension Mechanisms for DNS (EDNS(0))
+Y https://tools.ietf.org/html/rfc6944 → Applicability Statement: DNS Security (DNSSEC) DNSKEY Algorithm Implementation Status
+Y https://tools.ietf.org/html/rfc6975 → Signaling Cryptographic Algorithm Understanding in DNS Security Extensions (DNSSEC)
+Y https://tools.ietf.org/html/rfc7129 → Authenticated Denial of Existence in the DNS
+Y https://tools.ietf.org/html/rfc7646 → Definition and Use of DNSSEC Negative Trust Anchors
+~ https://tools.ietf.org/html/rfc7719 → DNS Terminology
+
+Also relevant:
+
+ https://www.iab.org/documents/correspondence-reports-documents/2013-2/iab-statement-dotless-domains-considered-harmful/
diff --git a/src/grp-resolve/systemd-resolved/dnssec-trust-anchors.d.xml b/src/grp-resolve/systemd-resolved/dnssec-trust-anchors.d.xml
new file mode 100644
index 0000000000..4bdc167f79
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/dnssec-trust-anchors.d.xml
@@ -0,0 +1,200 @@
+<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+ "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+
+<!--
+ This file is part of systemd.
+
+ Copyright 2016 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="dnssec-trust-anchors.d" conditional='ENABLE_RESOLVED'
+ xmlns:xi="http://www.w3.org/2001/XInclude">
+ <refentryinfo>
+ <title>dnssec-trust-anchors.d</title>
+ <productname>systemd</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>dnssec-trust-anchors.d</refentrytitle>
+ <manvolnum>5</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>dnssec-trust-anchors.d</refname>
+ <refname>systemd.positive</refname>
+ <refname>systemd.negative</refname>
+ <refpurpose>DNSSEC trust anchor configuration files</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <para><filename>/etc/dnssec-trust-anchors.d/*.positive</filename></para>
+ <para><filename>/run/dnssec-trust-anchors.d/*.positive</filename></para>
+ <para><filename>/usr/lib/dnssec-trust-anchors.d/*.positive</filename></para>
+ <para><filename>/etc/dnssec-trust-anchors.d/*.negative</filename></para>
+ <para><filename>/run/dnssec-trust-anchors.d/*.negative</filename></para>
+ <para><filename>/usr/lib/dnssec-trust-anchors.d/*.negative</filename></para>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para>The DNSSEC trust anchor configuration files define positive
+ and negative trust anchors
+ <citerefentry><refentrytitle>systemd-resolved.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ bases DNSSEC integrity proofs on.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Positive Trust Anchors</title>
+
+ <para>Positive trust anchor configuration files contain DNSKEY and
+ DS resource record definitions to use as base for DNSSEC integrity
+ proofs. See <ulink
+ url="https://tools.ietf.org/html/rfc4035#section-4.4">RFC 4035,
+ Section 4.4</ulink> for more information about DNSSEC trust
+ anchors.</para>
+
+ <para>Positive trust anchors are read from files with the suffix
+ <filename>.positive</filename> located in
+ <filename>/etc/dnssec-trust-anchors.d/</filename>,
+ <filename>/run/dnssec-trust-anchors.d/</filename> and
+ <filename>/usr/lib/dnssec-trust-anchors.d/</filename>. These
+ directories are searched in the specified order, and a trust
+ anchor file of the same name in an earlier path overrides a trust
+ anchor files in a later path. To disable a trust anchor file
+ shipped in <filename>/usr/lib/dnssec-trust-anchors.d/</filename>
+ it is sufficient to provide an identically-named file in
+ <filename>/etc/dnssec-trust-anchors.d/</filename> or
+ <filename>/run/dnssec-trust-anchors.d/</filename> that is either
+ empty or a symlink to <filename>/dev/null</filename> ("masked").</para>
+
+ <para>Positive trust anchor files are simple text files resembling
+ DNS zone files, as documented in <ulink
+ url="https://tools.ietf.org/html/rfc1035#section-5">RFC 1035, Section
+ 5</ulink>. One DS or DNSKEY resource record may be listed per
+ line. Empty lines and lines starting with a semicolon
+ (<literal>;</literal>) are ignored and considered comments. A DS
+ resource record is specified like in the following example:</para>
+
+ <programlisting>. IN DS 19036 8 2 49aac11d7b6f6446702e54a1607371607a1a41855200fd2ce1cdde32f24e8fb5</programlisting>
+
+ <para>The first word specifies the domain, use
+ <literal>.</literal> for the root domain. The domain may be
+ specified with or without trailing dot, which is considered
+ equivalent. The second word must be <literal>IN</literal> the
+ third word <literal>DS</literal>. The following words specify the
+ key tag, signature algorithm, digest algorithm, followed by the
+ hex-encoded key fingerprint. See <ulink
+ url="https://tools.ietf.org/html/rfc4034#section-5">RFC 4034,
+ Section 5</ulink> for details about the precise syntax and meaning
+ of these fields.</para>
+
+ <para>Alternatively, DNSKEY resource records may be used to define
+ trust anchors, like in the following example:</para>
+
+ <programlisting>. IN DNSKEY 257 3 8 AwEAAagAIKlVZrpC6Ia7gEzahOR+9W29euxhJhVVLOyQbSEW0O8gcCjFFVQUTf6v58fLjwBd0YI0EzrAcQqBGCzh/RStIoO8g0NfnfL2MTJRkxoXbfDaUeVPQuYEhg37NZWAJQ9VnMVDxP/VHL496M/QZxkjf5/Efucp2gaDX6RS6CXpoY68LsvPVjR0ZSwzz1apAzvN9dlzEheX7ICJBBtuA6G3LQpzW5hOA2hzCTMjJPJ8LbqF6dsV6DoBQzgul0sGIcGOYl7OyQdXfZ57relSQageu+ipAdTTJ25AsRTAoub8ONGcLmqrAmRLKBP1dfwhYB4N7knNnulqQxA+Uk1ihz0=</programlisting>
+
+ <para>The first word specifies the domain again, the second word
+ must be <literal>IN</literal>, followed by
+ <literal>DNSKEY</literal>. The subsequent words encode the DNSKEY
+ flags, protocol and algorithm fields, followed by the key data
+ encoded in Base64. See <ulink
+ url="https://tools.ietf.org/html/rfc4034#section-2">RFC 4034,
+ Section 2</ulink> for details about the precise syntax and meaning
+ of these fields.</para>
+
+ <para>If multiple DS or DNSKEY records are defined for the same
+ domain (possibly even in different trust anchor files), all keys
+ are used and are considered equivalent as base for DNSSEC
+ proofs.</para>
+
+ <para>Note that <filename>systemd-resolved</filename> will
+ automatically use a built-in trust anchor key for the Internet
+ root domain if no positive trust anchors are defined for the root
+ domain. In most cases it is hence unnecessary to define an
+ explicit key with trust anchor files. The built-in key is disabled
+ as soon as at least one trust anchor key for the root domain is
+ defined in trust anchor files.</para>
+
+ <para>It is generally recommended to encode trust anchors in DS
+ resource records, rather than DNSKEY resource records.</para>
+
+ <para>If a trust anchor specified via a DS record is found revoked
+ it is automatically removed from the trust anchor database for the
+ runtime. See <ulink url="https://tools.ietf.org/html/rfc5011">RFC
+ 5011</ulink> for details about revoked trust anchors. Note that
+ <filename>systemd-resolved</filename> will not update its trust
+ anchor database from DNS servers automatically. Instead, it is
+ recommended to update the resolver software or update the new
+ trust anchor via adding in new trust anchor files.</para>
+
+ <para>The current DNSSEC trust anchor for the Internet's root
+ domain is available at the <ulink
+ url="https://data.iana.org/root-anchors/root-anchors.xml">IANA
+ Trust Anchor and Keys</ulink> page.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Negative Trust Anchors</title>
+
+ <para>Negative trust anchors define domains where DNSSEC
+ validation shall be turned off. Negative trust anchor files are
+ found at the same location as positive trust anchor files, and
+ follow the same overriding rules. They are text files with the
+ <filename>.negative</filename> suffix. Empty lines and lines whose
+ first character is <literal>;</literal> are ignored. Each line
+ specifies one domain name where DNSSEC validation shall be
+ disabled on.</para>
+
+ <para>Negative trust anchors are useful to support private DNS
+ subtrees that are not referenced from the Internet DNS hierarchy,
+ and not signed.</para>
+
+ <para><ulink url="https://tools.ietf.org/html/rfc7646">RFC
+ 7646</ulink> for details on negative trust anchors.</para>
+
+ <para>If no negative trust anchor files are configured a built-in
+ set of well-known private DNS zone domains is used as negative
+ trust anchors.</para>
+
+ <para>It is also possibly to define per-interface negative trust
+ anchors using the <varname>DNSSECNegativeTrustAnchors=</varname>
+ setting in
+ <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ files.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-resolved.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>resolved.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
diff --git a/src/grp-resolve/systemd-resolved/org.freedesktop.resolve1.conf b/src/grp-resolve/systemd-resolved/org.freedesktop.resolve1.conf
new file mode 100644
index 0000000000..25b09774e5
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/org.freedesktop.resolve1.conf
@@ -0,0 +1,27 @@
+<?xml version="1.0"?> <!--*-nxml-*-->
+<!DOCTYPE busconfig PUBLIC "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
+ "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
+
+<!--
+ This file is part of systemd.
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+-->
+
+<busconfig>
+
+ <policy user="systemd-resolve">
+ <allow own="org.freedesktop.resolve1"/>
+ <allow send_destination="org.freedesktop.resolve1"/>
+ <allow receive_sender="org.freedesktop.resolve1"/>
+ </policy>
+
+ <policy context="default">
+ <allow send_destination="org.freedesktop.resolve1"/>
+ <allow receive_sender="org.freedesktop.resolve1"/>
+ </policy>
+
+</busconfig>
diff --git a/src/grp-resolve/systemd-resolved/org.freedesktop.resolve1.service b/src/grp-resolve/systemd-resolved/org.freedesktop.resolve1.service
new file mode 100644
index 0000000000..7ac5c323f0
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/org.freedesktop.resolve1.service
@@ -0,0 +1,12 @@
+# This file is part of systemd.
+#
+# systemd is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation; either version 2.1 of the License, or
+# (at your option) any later version.
+
+[D-BUS Service]
+Name=org.freedesktop.resolve1
+Exec=/bin/false
+User=root
+SystemdService=dbus-org.freedesktop.resolve1.service
diff --git a/src/grp-resolve/systemd-resolved/resolv.conf b/src/grp-resolve/systemd-resolved/resolv.conf
new file mode 100644
index 0000000000..b8034d6829
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolv.conf
@@ -0,0 +1,11 @@
+# This is a static resolv.conf file for connecting local clients to
+# systemd-resolved via its DNS stub listener on 127.0.0.53.
+#
+# Third party programs must not access this file directly, but only through the
+# symlink at /etc/resolv.conf. To manage resolv.conf(5) in a different way,
+# replace this symlink by a static file or a different symlink.
+#
+# See systemd-resolved.service(8) for details about the supported modes of
+# operation for /etc/resolv.conf.
+
+nameserver 127.0.0.53
diff --git a/src/grp-resolve/systemd-resolved/resolved-bus.c b/src/grp-resolve/systemd-resolved/resolved-bus.c
new file mode 100644
index 0000000000..ec63fb2900
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-bus.c
@@ -0,0 +1,1690 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "basic-dns/resolved-def.h"
+#include "sd-bus/bus-common-errors.h"
+#include "sd-bus/bus-util.h"
+#include "systemd-basic/alloc-util.h"
+#include "systemd-shared/dns-domain.h"
+
+#include "resolved-bus.h"
+#include "resolved-dns-synthesize.h"
+#include "resolved-link-bus.h"
+
+static int reply_query_state(DnsQuery *q) {
+
+ switch (q->state) {
+
+ case DNS_TRANSACTION_NO_SERVERS:
+ return sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_NAME_SERVERS, "No appropriate name servers or networks for name found");
+
+ case DNS_TRANSACTION_TIMEOUT:
+ return sd_bus_reply_method_errorf(q->request, SD_BUS_ERROR_TIMEOUT, "Query timed out");
+
+ case DNS_TRANSACTION_ATTEMPTS_MAX_REACHED:
+ return sd_bus_reply_method_errorf(q->request, SD_BUS_ERROR_TIMEOUT, "All attempts to contact name servers or networks failed");
+
+ case DNS_TRANSACTION_INVALID_REPLY:
+ return sd_bus_reply_method_errorf(q->request, BUS_ERROR_INVALID_REPLY, "Received invalid reply");
+
+ case DNS_TRANSACTION_ERRNO:
+ return sd_bus_reply_method_errnof(q->request, q->answer_errno, "Lookup failed due to system error: %m");
+
+ case DNS_TRANSACTION_ABORTED:
+ return sd_bus_reply_method_errorf(q->request, BUS_ERROR_ABORTED, "Query aborted");
+
+ case DNS_TRANSACTION_DNSSEC_FAILED:
+ return sd_bus_reply_method_errorf(q->request, BUS_ERROR_DNSSEC_FAILED, "DNSSEC validation failed: %s",
+ dnssec_result_to_string(q->answer_dnssec_result));
+
+ case DNS_TRANSACTION_NO_TRUST_ANCHOR:
+ return sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_TRUST_ANCHOR, "No suitable trust anchor known");
+
+ case DNS_TRANSACTION_RR_TYPE_UNSUPPORTED:
+ return sd_bus_reply_method_errorf(q->request, BUS_ERROR_RR_TYPE_UNSUPPORTED, "Server does not support requested resource record type");
+
+ case DNS_TRANSACTION_NETWORK_DOWN:
+ return sd_bus_reply_method_errorf(q->request, BUS_ERROR_NETWORK_DOWN, "Network is down");
+
+ case DNS_TRANSACTION_NOT_FOUND:
+ /* We return this as NXDOMAIN. This is only generated when a host doesn't implement LLMNR/TCP, and we
+ * thus quickly know that we cannot resolve an in-addr.arpa or ip6.arpa address. */
+ return sd_bus_reply_method_errorf(q->request, _BUS_ERROR_DNS "NXDOMAIN", "'%s' not found", dns_query_string(q));
+
+ case DNS_TRANSACTION_RCODE_FAILURE: {
+ _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+
+ if (q->answer_rcode == DNS_RCODE_NXDOMAIN)
+ sd_bus_error_setf(&error, _BUS_ERROR_DNS "NXDOMAIN", "'%s' not found", dns_query_string(q));
+ else {
+ const char *rc, *n;
+ char p[DECIMAL_STR_MAX(q->answer_rcode)];
+
+ rc = dns_rcode_to_string(q->answer_rcode);
+ if (!rc) {
+ sprintf(p, "%i", q->answer_rcode);
+ rc = p;
+ }
+
+ n = strjoina(_BUS_ERROR_DNS, rc);
+ sd_bus_error_setf(&error, n, "Could not resolve '%s', server or network returned error %s", dns_query_string(q), rc);
+ }
+
+ return sd_bus_reply_method_error(q->request, &error);
+ }
+
+ case DNS_TRANSACTION_NULL:
+ case DNS_TRANSACTION_PENDING:
+ case DNS_TRANSACTION_VALIDATING:
+ case DNS_TRANSACTION_SUCCESS:
+ default:
+ assert_not_reached("Impossible state");
+ }
+}
+
+static int append_address(sd_bus_message *reply, DnsResourceRecord *rr, int ifindex) {
+ int r;
+
+ assert(reply);
+ assert(rr);
+
+ r = sd_bus_message_open_container(reply, 'r', "iiay");
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_append(reply, "i", ifindex);
+ if (r < 0)
+ return r;
+
+ if (rr->key->type == DNS_TYPE_A) {
+ r = sd_bus_message_append(reply, "i", AF_INET);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_append_array(reply, 'y', &rr->a.in_addr, sizeof(struct in_addr));
+
+ } else if (rr->key->type == DNS_TYPE_AAAA) {
+ r = sd_bus_message_append(reply, "i", AF_INET6);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_append_array(reply, 'y', &rr->aaaa.in6_addr, sizeof(struct in6_addr));
+ } else
+ return -EAFNOSUPPORT;
+
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_close_container(reply);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+static void bus_method_resolve_hostname_complete(DnsQuery *q) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *canonical = NULL;
+ _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+ _cleanup_free_ char *normalized = NULL;
+ DnsResourceRecord *rr;
+ unsigned added = 0;
+ int ifindex, r;
+
+ assert(q);
+
+ if (q->state != DNS_TRANSACTION_SUCCESS) {
+ r = reply_query_state(q);
+ goto finish;
+ }
+
+ r = dns_query_process_cname(q);
+ if (r == -ELOOP) {
+ r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_CNAME_LOOP, "CNAME loop detected, or CNAME resolving disabled on '%s'", dns_query_string(q));
+ goto finish;
+ }
+ if (r < 0)
+ goto finish;
+ if (r == DNS_QUERY_RESTARTED) /* This was a cname, and the query was restarted. */
+ return;
+
+ r = sd_bus_message_new_method_return(q->request, &reply);
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_message_open_container(reply, 'a', "(iiay)");
+ if (r < 0)
+ goto finish;
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, q->answer) {
+ DnsQuestion *question;
+
+ question = dns_query_question_for_protocol(q, q->answer_protocol);
+
+ r = dns_question_matches_rr(question, rr, DNS_SEARCH_DOMAIN_NAME(q->answer_search_domain));
+ if (r < 0)
+ goto finish;
+ if (r == 0)
+ continue;
+
+ r = append_address(reply, rr, ifindex);
+ if (r < 0)
+ goto finish;
+
+ if (!canonical)
+ canonical = dns_resource_record_ref(rr);
+
+ added++;
+ }
+
+ if (added <= 0) {
+ r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_SUCH_RR, "'%s' does not have any RR of the requested type", dns_query_string(q));
+ goto finish;
+ }
+
+ r = sd_bus_message_close_container(reply);
+ if (r < 0)
+ goto finish;
+
+ /* The key names are not necessarily normalized, make sure that they are when we return them to our bus
+ * clients. */
+ r = dns_name_normalize(dns_resource_key_name(canonical->key), &normalized);
+ if (r < 0)
+ goto finish;
+
+ /* Return the precise spelling and uppercasing and CNAME target reported by the server */
+ assert(canonical);
+ r = sd_bus_message_append(
+ reply, "st",
+ normalized,
+ SD_RESOLVED_FLAGS_MAKE(q->answer_protocol, q->answer_family, q->answer_authenticated));
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_send(q->manager->bus, reply, NULL);
+
+finish:
+ if (r < 0) {
+ log_error_errno(r, "Failed to send hostname reply: %m");
+ sd_bus_reply_method_errno(q->request, r, NULL);
+ }
+
+ dns_query_free(q);
+}
+
+static int check_ifindex_flags(int ifindex, uint64_t *flags, uint64_t ok, sd_bus_error *error) {
+ assert(flags);
+
+ if (ifindex < 0)
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid interface index");
+
+ if (*flags & ~(SD_RESOLVED_PROTOCOLS_ALL|SD_RESOLVED_NO_CNAME|ok))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid flags parameter");
+
+ if ((*flags & SD_RESOLVED_PROTOCOLS_ALL) == 0) /* If no protocol is enabled, enable all */
+ *flags |= SD_RESOLVED_PROTOCOLS_ALL;
+
+ return 0;
+}
+
+static int parse_as_address(sd_bus_message *m, int ifindex, const char *hostname, int family, uint64_t flags) {
+ _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+ _cleanup_free_ char *canonical = NULL;
+ union in_addr_union parsed;
+ int r, ff, parsed_ifindex = 0;
+
+ /* Check if the hostname is actually already an IP address formatted as string. In that case just parse it,
+ * let's not attempt to look it up. */
+
+ r = in_addr_ifindex_from_string_auto(hostname, &ff, &parsed, &parsed_ifindex);
+ if (r < 0) /* not an address */
+ return 0;
+
+ if (family != AF_UNSPEC && ff != family)
+ return sd_bus_reply_method_errorf(m, BUS_ERROR_NO_SUCH_RR, "The specified address is not of the requested family.");
+ if (ifindex > 0 && parsed_ifindex > 0 && parsed_ifindex != ifindex)
+ return sd_bus_reply_method_errorf(m, BUS_ERROR_NO_SUCH_RR, "The specified address interface index does not match requested interface.");
+
+ if (parsed_ifindex > 0)
+ ifindex = parsed_ifindex;
+
+ r = sd_bus_message_new_method_return(m, &reply);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_open_container(reply, 'a', "(iiay)");
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_open_container(reply, 'r', "iiay");
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_append(reply, "ii", ifindex, ff);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_append_array(reply, 'y', &parsed, FAMILY_ADDRESS_SIZE(ff));
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_close_container(reply);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_close_container(reply);
+ if (r < 0)
+ return r;
+
+ /* When an IP address is specified we just return it as canonical name, in order to avoid a DNS
+ * look-up. However, we reformat it to make sure it's in a truly canonical form (i.e. on IPv6 the inner
+ * omissions are always done the same way). */
+ r = in_addr_ifindex_to_string(ff, &parsed, ifindex, &canonical);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_append(reply, "st", canonical,
+ SD_RESOLVED_FLAGS_MAKE(dns_synthesize_protocol(flags), ff, true));
+ if (r < 0)
+ return r;
+
+ return sd_bus_send(sd_bus_message_get_bus(m), reply, NULL);
+}
+
+static int bus_method_resolve_hostname(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ _cleanup_(dns_question_unrefp) DnsQuestion *question_idna = NULL, *question_utf8 = NULL;
+ Manager *m = userdata;
+ const char *hostname;
+ int family, ifindex;
+ uint64_t flags;
+ DnsQuery *q;
+ int r;
+
+ assert(message);
+ assert(m);
+
+ assert_cc(sizeof(int) == sizeof(int32_t));
+
+ r = sd_bus_message_read(message, "isit", &ifindex, &hostname, &family, &flags);
+ if (r < 0)
+ return r;
+
+ if (!IN_SET(family, AF_INET, AF_INET6, AF_UNSPEC))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Unknown address family %i", family);
+
+ r = check_ifindex_flags(ifindex, &flags, SD_RESOLVED_NO_SEARCH, error);
+ if (r < 0)
+ return r;
+
+ r = parse_as_address(message, ifindex, hostname, family, flags);
+ if (r != 0)
+ return r;
+
+ r = dns_name_is_valid(hostname);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid hostname '%s'", hostname);
+
+ r = dns_question_new_address(&question_utf8, family, hostname, false);
+ if (r < 0)
+ return r;
+
+ r = dns_question_new_address(&question_idna, family, hostname, true);
+ if (r < 0)
+ return r;
+
+ r = dns_query_new(m, &q, question_utf8, question_idna, ifindex, flags);
+ if (r < 0)
+ return r;
+
+ q->request = sd_bus_message_ref(message);
+ q->request_family = family;
+ q->complete = bus_method_resolve_hostname_complete;
+ q->suppress_unroutable_family = family == AF_UNSPEC;
+
+ r = dns_query_bus_track(q, message);
+ if (r < 0)
+ goto fail;
+
+ r = dns_query_go(q);
+ if (r < 0)
+ goto fail;
+
+ return 1;
+
+fail:
+ dns_query_free(q);
+ return r;
+}
+
+static void bus_method_resolve_address_complete(DnsQuery *q) {
+ _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+ DnsQuestion *question;
+ DnsResourceRecord *rr;
+ unsigned added = 0;
+ int ifindex, r;
+
+ assert(q);
+
+ if (q->state != DNS_TRANSACTION_SUCCESS) {
+ r = reply_query_state(q);
+ goto finish;
+ }
+
+ r = dns_query_process_cname(q);
+ if (r == -ELOOP) {
+ r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_CNAME_LOOP, "CNAME loop detected, or CNAME resolving disabled on '%s'", dns_query_string(q));
+ goto finish;
+ }
+ if (r < 0)
+ goto finish;
+ if (r == DNS_QUERY_RESTARTED) /* This was a cname, and the query was restarted. */
+ return;
+
+ r = sd_bus_message_new_method_return(q->request, &reply);
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_message_open_container(reply, 'a', "(is)");
+ if (r < 0)
+ goto finish;
+
+ question = dns_query_question_for_protocol(q, q->answer_protocol);
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, q->answer) {
+ _cleanup_free_ char *normalized = NULL;
+
+ r = dns_question_matches_rr(question, rr, NULL);
+ if (r < 0)
+ goto finish;
+ if (r == 0)
+ continue;
+
+ r = dns_name_normalize(rr->ptr.name, &normalized);
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_message_append(reply, "(is)", ifindex, normalized);
+ if (r < 0)
+ goto finish;
+
+ added++;
+ }
+
+ if (added <= 0) {
+ _cleanup_free_ char *ip = NULL;
+
+ (void) in_addr_to_string(q->request_family, &q->request_address, &ip);
+ r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_SUCH_RR,
+ "Address '%s' does not have any RR of requested type", strnull(ip));
+ goto finish;
+ }
+
+ r = sd_bus_message_close_container(reply);
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_message_append(reply, "t", SD_RESOLVED_FLAGS_MAKE(q->answer_protocol, q->answer_family, q->answer_authenticated));
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_send(q->manager->bus, reply, NULL);
+
+finish:
+ if (r < 0) {
+ log_error_errno(r, "Failed to send address reply: %m");
+ sd_bus_reply_method_errno(q->request, r, NULL);
+ }
+
+ dns_query_free(q);
+}
+
+static int bus_method_resolve_address(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+ Manager *m = userdata;
+ int family, ifindex;
+ uint64_t flags;
+ const void *d;
+ DnsQuery *q;
+ size_t sz;
+ int r;
+
+ assert(message);
+ assert(m);
+
+ assert_cc(sizeof(int) == sizeof(int32_t));
+
+ r = sd_bus_message_read(message, "ii", &ifindex, &family);
+ if (r < 0)
+ return r;
+
+ if (!IN_SET(family, AF_INET, AF_INET6))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Unknown address family %i", family);
+
+ r = sd_bus_message_read_array(message, 'y', &d, &sz);
+ if (r < 0)
+ return r;
+
+ if (sz != FAMILY_ADDRESS_SIZE(family))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid address size");
+
+ r = sd_bus_message_read(message, "t", &flags);
+ if (r < 0)
+ return r;
+
+ r = check_ifindex_flags(ifindex, &flags, 0, error);
+ if (r < 0)
+ return r;
+
+ r = dns_question_new_reverse(&question, family, d);
+ if (r < 0)
+ return r;
+
+ r = dns_query_new(m, &q, question, question, ifindex, flags|SD_RESOLVED_NO_SEARCH);
+ if (r < 0)
+ return r;
+
+ q->request = sd_bus_message_ref(message);
+ q->request_family = family;
+ memcpy(&q->request_address, d, sz);
+ q->complete = bus_method_resolve_address_complete;
+
+ r = dns_query_bus_track(q, message);
+ if (r < 0)
+ goto fail;
+
+ r = dns_query_go(q);
+ if (r < 0)
+ goto fail;
+
+ return 1;
+
+fail:
+ dns_query_free(q);
+ return r;
+}
+
+static int bus_message_append_rr(sd_bus_message *m, DnsResourceRecord *rr, int ifindex) {
+ int r;
+
+ assert(m);
+ assert(rr);
+
+ r = sd_bus_message_open_container(m, 'r', "iqqay");
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_append(m, "iqq",
+ ifindex,
+ rr->key->class,
+ rr->key->type);
+ if (r < 0)
+ return r;
+
+ r = dns_resource_record_to_wire_format(rr, false);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_append_array(m, 'y', rr->wire_format, rr->wire_format_size);
+ if (r < 0)
+ return r;
+
+ return sd_bus_message_close_container(m);
+}
+
+static void bus_method_resolve_record_complete(DnsQuery *q) {
+ _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+ DnsResourceRecord *rr;
+ DnsQuestion *question;
+ unsigned added = 0;
+ int ifindex;
+ int r;
+
+ assert(q);
+
+ if (q->state != DNS_TRANSACTION_SUCCESS) {
+ r = reply_query_state(q);
+ goto finish;
+ }
+
+ r = dns_query_process_cname(q);
+ if (r == -ELOOP) {
+ r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_CNAME_LOOP, "CNAME loop detected, or CNAME resolving disabled on '%s'", dns_query_string(q));
+ goto finish;
+ }
+ if (r < 0)
+ goto finish;
+ if (r == DNS_QUERY_RESTARTED) /* This was a cname, and the query was restarted. */
+ return;
+
+ r = sd_bus_message_new_method_return(q->request, &reply);
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_message_open_container(reply, 'a', "(iqqay)");
+ if (r < 0)
+ goto finish;
+
+ question = dns_query_question_for_protocol(q, q->answer_protocol);
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, q->answer) {
+ r = dns_question_matches_rr(question, rr, NULL);
+ if (r < 0)
+ goto finish;
+ if (r == 0)
+ continue;
+
+ r = bus_message_append_rr(reply, rr, ifindex);
+ if (r < 0)
+ goto finish;
+
+ added++;
+ }
+
+ if (added <= 0) {
+ r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_SUCH_RR, "Name '%s' does not have any RR of the requested type", dns_query_string(q));
+ goto finish;
+ }
+
+ r = sd_bus_message_close_container(reply);
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_message_append(reply, "t", SD_RESOLVED_FLAGS_MAKE(q->answer_protocol, q->answer_family, q->answer_authenticated));
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_send(q->manager->bus, reply, NULL);
+
+finish:
+ if (r < 0) {
+ log_error_errno(r, "Failed to send record reply: %m");
+ sd_bus_reply_method_errno(q->request, r, NULL);
+ }
+
+ dns_query_free(q);
+}
+
+static int bus_method_resolve_record(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+ _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+ Manager *m = userdata;
+ uint16_t class, type;
+ const char *name;
+ int r, ifindex;
+ uint64_t flags;
+ DnsQuery *q;
+
+ assert(message);
+ assert(m);
+
+ assert_cc(sizeof(int) == sizeof(int32_t));
+
+ r = sd_bus_message_read(message, "isqqt", &ifindex, &name, &class, &type, &flags);
+ if (r < 0)
+ return r;
+
+ r = dns_name_is_valid(name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid name '%s'", name);
+
+ if (!dns_type_is_valid_query(type))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Specified resource record type %" PRIu16 " may not be used in a query.", type);
+ if (dns_type_is_zone_transer(type))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_NOT_SUPPORTED, "Zone transfers not permitted via this programming interface.");
+ if (dns_type_is_obsolete(type))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_NOT_SUPPORTED, "Specified DNS resource record type %" PRIu16 " is obsolete.", type);
+
+ r = check_ifindex_flags(ifindex, &flags, 0, error);
+ if (r < 0)
+ return r;
+
+ question = dns_question_new(1);
+ if (!question)
+ return -ENOMEM;
+
+ key = dns_resource_key_new(class, type, name);
+ if (!key)
+ return -ENOMEM;
+
+ r = dns_question_add(question, key);
+ if (r < 0)
+ return r;
+
+ r = dns_query_new(m, &q, question, question, ifindex, flags|SD_RESOLVED_NO_SEARCH);
+ if (r < 0)
+ return r;
+
+ /* Let's request that the TTL is fixed up for locally cached entries, after all we return it in the wire format
+ * blob */
+ q->clamp_ttl = true;
+
+ q->request = sd_bus_message_ref(message);
+ q->complete = bus_method_resolve_record_complete;
+
+ r = dns_query_bus_track(q, message);
+ if (r < 0)
+ goto fail;
+
+ r = dns_query_go(q);
+ if (r < 0)
+ goto fail;
+
+ return 1;
+
+fail:
+ dns_query_free(q);
+ return r;
+}
+
+static int append_srv(DnsQuery *q, sd_bus_message *reply, DnsResourceRecord *rr) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *canonical = NULL;
+ _cleanup_free_ char *normalized = NULL;
+ DnsQuery *aux;
+ int r;
+
+ assert(q);
+ assert(reply);
+ assert(rr);
+ assert(rr->key);
+
+ if (rr->key->type != DNS_TYPE_SRV)
+ return 0;
+
+ if ((q->flags & SD_RESOLVED_NO_ADDRESS) == 0) {
+ /* First, let's see if we could find an appropriate A or AAAA
+ * record for the SRV record */
+ LIST_FOREACH(auxiliary_queries, aux, q->auxiliary_queries) {
+ DnsResourceRecord *zz;
+ DnsQuestion *question;
+
+ if (aux->state != DNS_TRANSACTION_SUCCESS)
+ continue;
+ if (aux->auxiliary_result != 0)
+ continue;
+
+ question = dns_query_question_for_protocol(aux, aux->answer_protocol);
+
+ r = dns_name_equal(dns_question_first_name(question), rr->srv.name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ DNS_ANSWER_FOREACH(zz, aux->answer) {
+
+ r = dns_question_matches_rr(question, zz, NULL);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ canonical = dns_resource_record_ref(zz);
+ break;
+ }
+
+ if (canonical)
+ break;
+ }
+
+ /* Is there are successful A/AAAA lookup for this SRV RR? If not, don't add it */
+ if (!canonical)
+ return 0;
+ }
+
+ r = sd_bus_message_open_container(reply, 'r', "qqqsa(iiay)s");
+ if (r < 0)
+ return r;
+
+ r = dns_name_normalize(rr->srv.name, &normalized);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_append(
+ reply,
+ "qqqs",
+ rr->srv.priority, rr->srv.weight, rr->srv.port, normalized);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_open_container(reply, 'a', "(iiay)");
+ if (r < 0)
+ return r;
+
+ if ((q->flags & SD_RESOLVED_NO_ADDRESS) == 0) {
+ LIST_FOREACH(auxiliary_queries, aux, q->auxiliary_queries) {
+ DnsResourceRecord *zz;
+ DnsQuestion *question;
+ int ifindex;
+
+ if (aux->state != DNS_TRANSACTION_SUCCESS)
+ continue;
+ if (aux->auxiliary_result != 0)
+ continue;
+
+ question = dns_query_question_for_protocol(aux, aux->answer_protocol);
+
+ r = dns_name_equal(dns_question_first_name(question), rr->srv.name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ DNS_ANSWER_FOREACH_IFINDEX(zz, ifindex, aux->answer) {
+
+ r = dns_question_matches_rr(question, zz, NULL);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ r = append_address(reply, zz, ifindex);
+ if (r < 0)
+ return r;
+ }
+ }
+ }
+
+ r = sd_bus_message_close_container(reply);
+ if (r < 0)
+ return r;
+
+ if (canonical) {
+ normalized = mfree(normalized);
+
+ r = dns_name_normalize(dns_resource_key_name(canonical->key), &normalized);
+ if (r < 0)
+ return r;
+ }
+
+ /* Note that above we appended the hostname as encoded in the
+ * SRV, and here the canonical hostname this maps to. */
+ r = sd_bus_message_append(reply, "s", normalized);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_close_container(reply);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+static int append_txt(sd_bus_message *reply, DnsResourceRecord *rr) {
+ DnsTxtItem *i;
+ int r;
+
+ assert(reply);
+ assert(rr);
+ assert(rr->key);
+
+ if (rr->key->type != DNS_TYPE_TXT)
+ return 0;
+
+ LIST_FOREACH(items, i, rr->txt.items) {
+
+ if (i->length <= 0)
+ continue;
+
+ r = sd_bus_message_append_array(reply, 'y', i->data, i->length);
+ if (r < 0)
+ return r;
+ }
+
+ return 1;
+}
+
+static void resolve_service_all_complete(DnsQuery *q) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *canonical = NULL;
+ _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+ _cleanup_free_ char *name = NULL, *type = NULL, *domain = NULL;
+ DnsQuestion *question;
+ DnsResourceRecord *rr;
+ unsigned added = 0;
+ DnsQuery *aux;
+ int r;
+
+ assert(q);
+
+ if (q->block_all_complete > 0)
+ return;
+
+ if ((q->flags & SD_RESOLVED_NO_ADDRESS) == 0) {
+ DnsQuery *bad = NULL;
+ bool have_success = false;
+
+ LIST_FOREACH(auxiliary_queries, aux, q->auxiliary_queries) {
+
+ switch (aux->state) {
+
+ case DNS_TRANSACTION_PENDING:
+ /* If an auxiliary query is still pending, let's wait */
+ return;
+
+ case DNS_TRANSACTION_SUCCESS:
+ if (aux->auxiliary_result == 0)
+ have_success = true;
+ else
+ bad = aux;
+ break;
+
+ default:
+ bad = aux;
+ break;
+ }
+ }
+
+ if (!have_success) {
+ /* We can only return one error, hence pick the last error we encountered */
+
+ assert(bad);
+
+ if (bad->state == DNS_TRANSACTION_SUCCESS) {
+ assert(bad->auxiliary_result != 0);
+
+ if (bad->auxiliary_result == -ELOOP) {
+ r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_CNAME_LOOP, "CNAME loop detected, or CNAME resolving disabled on '%s'", dns_query_string(bad));
+ goto finish;
+ }
+
+ r = bad->auxiliary_result;
+ goto finish;
+ }
+
+ r = reply_query_state(bad);
+ goto finish;
+ }
+ }
+
+ r = sd_bus_message_new_method_return(q->request, &reply);
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_message_open_container(reply, 'a', "(qqqsa(iiay)s)");
+ if (r < 0)
+ goto finish;
+
+ question = dns_query_question_for_protocol(q, q->answer_protocol);
+ DNS_ANSWER_FOREACH(rr, q->answer) {
+ r = dns_question_matches_rr(question, rr, NULL);
+ if (r < 0)
+ goto finish;
+ if (r == 0)
+ continue;
+
+ r = append_srv(q, reply, rr);
+ if (r < 0)
+ goto finish;
+ if (r == 0) /* not an SRV record */
+ continue;
+
+ if (!canonical)
+ canonical = dns_resource_record_ref(rr);
+
+ added++;
+ }
+
+ if (added <= 0) {
+ r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_SUCH_RR, "'%s' does not have any RR of the requested type", dns_query_string(q));
+ goto finish;
+ }
+
+ r = sd_bus_message_close_container(reply);
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_message_open_container(reply, 'a', "ay");
+ if (r < 0)
+ goto finish;
+
+ DNS_ANSWER_FOREACH(rr, q->answer) {
+ r = dns_question_matches_rr(question, rr, NULL);
+ if (r < 0)
+ goto finish;
+ if (r == 0)
+ continue;
+
+ r = append_txt(reply, rr);
+ if (r < 0)
+ goto finish;
+ }
+
+ r = sd_bus_message_close_container(reply);
+ if (r < 0)
+ goto finish;
+
+ assert(canonical);
+ r = dns_service_split(dns_resource_key_name(canonical->key), &name, &type, &domain);
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_message_append(
+ reply,
+ "ssst",
+ name, type, domain,
+ SD_RESOLVED_FLAGS_MAKE(q->answer_protocol, q->answer_family, q->answer_authenticated));
+ if (r < 0)
+ goto finish;
+
+ r = sd_bus_send(q->manager->bus, reply, NULL);
+
+finish:
+ if (r < 0) {
+ log_error_errno(r, "Failed to send service reply: %m");
+ sd_bus_reply_method_errno(q->request, r, NULL);
+ }
+
+ dns_query_free(q);
+}
+
+static void resolve_service_hostname_complete(DnsQuery *q) {
+ int r;
+
+ assert(q);
+ assert(q->auxiliary_for);
+
+ if (q->state != DNS_TRANSACTION_SUCCESS) {
+ resolve_service_all_complete(q->auxiliary_for);
+ return;
+ }
+
+ r = dns_query_process_cname(q);
+ if (r == DNS_QUERY_RESTARTED) /* This was a cname, and the query was restarted. */
+ return;
+
+ /* This auxiliary lookup is finished or failed, let's see if all are finished now. */
+ q->auxiliary_result = r;
+ resolve_service_all_complete(q->auxiliary_for);
+}
+
+static int resolve_service_hostname(DnsQuery *q, DnsResourceRecord *rr, int ifindex) {
+ _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+ DnsQuery *aux;
+ int r;
+
+ assert(q);
+ assert(rr);
+ assert(rr->key);
+ assert(rr->key->type == DNS_TYPE_SRV);
+
+ /* OK, we found an SRV record for the service. Let's resolve
+ * the hostname included in it */
+
+ r = dns_question_new_address(&question, q->request_family, rr->srv.name, false);
+ if (r < 0)
+ return r;
+
+ r = dns_query_new(q->manager, &aux, question, question, ifindex, q->flags|SD_RESOLVED_NO_SEARCH);
+ if (r < 0)
+ return r;
+
+ aux->request_family = q->request_family;
+ aux->complete = resolve_service_hostname_complete;
+
+ r = dns_query_make_auxiliary(aux, q);
+ if (r == -EAGAIN) {
+ /* Too many auxiliary lookups? If so, don't complain,
+ * let's just not add this one, we already have more
+ * than enough */
+
+ dns_query_free(aux);
+ return 0;
+ }
+ if (r < 0)
+ goto fail;
+
+ /* Note that auxiliary queries do not track the original bus
+ * client, only the primary request does that. */
+
+ r = dns_query_go(aux);
+ if (r < 0)
+ goto fail;
+
+ return 1;
+
+fail:
+ dns_query_free(aux);
+ return r;
+}
+
+static void bus_method_resolve_service_complete(DnsQuery *q) {
+ bool has_root_domain = false;
+ DnsResourceRecord *rr;
+ DnsQuestion *question;
+ unsigned found = 0;
+ int ifindex, r;
+
+ assert(q);
+
+ if (q->state != DNS_TRANSACTION_SUCCESS) {
+ r = reply_query_state(q);
+ goto finish;
+ }
+
+ r = dns_query_process_cname(q);
+ if (r == -ELOOP) {
+ r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_CNAME_LOOP, "CNAME loop detected, or CNAME resolving disabled on '%s'", dns_query_string(q));
+ goto finish;
+ }
+ if (r < 0)
+ goto finish;
+ if (r == DNS_QUERY_RESTARTED) /* This was a cname, and the query was restarted. */
+ return;
+
+ question = dns_query_question_for_protocol(q, q->answer_protocol);
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, q->answer) {
+ r = dns_question_matches_rr(question, rr, NULL);
+ if (r < 0)
+ goto finish;
+ if (r == 0)
+ continue;
+
+ if (rr->key->type != DNS_TYPE_SRV)
+ continue;
+
+ if (dns_name_is_root(rr->srv.name)) {
+ has_root_domain = true;
+ continue;
+ }
+
+ if ((q->flags & SD_RESOLVED_NO_ADDRESS) == 0) {
+ q->block_all_complete++;
+ r = resolve_service_hostname(q, rr, ifindex);
+ q->block_all_complete--;
+
+ if (r < 0)
+ goto finish;
+ }
+
+ found++;
+ }
+
+ if (has_root_domain && found <= 0) {
+ /* If there's exactly one SRV RR and it uses
+ * the root domain as host name, then the
+ * service is explicitly not offered on the
+ * domain. Report this as a recognizable
+ * error. See RFC 2782, Section "Usage
+ * Rules". */
+ r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_SUCH_SERVICE, "'%s' does not provide the requested service", dns_query_string(q));
+ goto finish;
+ }
+
+ if (found <= 0) {
+ r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_SUCH_RR, "'%s' does not have any RR of the requested type", dns_query_string(q));
+ goto finish;
+ }
+
+ /* Maybe we are already finished? check now... */
+ resolve_service_all_complete(q);
+ return;
+
+finish:
+ if (r < 0) {
+ log_error_errno(r, "Failed to send service reply: %m");
+ sd_bus_reply_method_errno(q->request, r, NULL);
+ }
+
+ dns_query_free(q);
+}
+
+static int bus_method_resolve_service(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ _cleanup_(dns_question_unrefp) DnsQuestion *question_idna = NULL, *question_utf8 = NULL;
+ const char *name, *type, *domain;
+ Manager *m = userdata;
+ int family, ifindex;
+ uint64_t flags;
+ DnsQuery *q;
+ int r;
+
+ assert(message);
+ assert(m);
+
+ assert_cc(sizeof(int) == sizeof(int32_t));
+
+ r = sd_bus_message_read(message, "isssit", &ifindex, &name, &type, &domain, &family, &flags);
+ if (r < 0)
+ return r;
+
+ if (!IN_SET(family, AF_INET, AF_INET6, AF_UNSPEC))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Unknown address family %i", family);
+
+ if (isempty(name))
+ name = NULL;
+ else if (!dns_service_name_is_valid(name))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid service name '%s'", name);
+
+ if (isempty(type))
+ type = NULL;
+ else if (!dns_srv_type_is_valid(type))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid SRV service type '%s'", type);
+
+ r = dns_name_is_valid(domain);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid domain '%s'", domain);
+
+ if (name && !type)
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Service name cannot be specified without service type.");
+
+ r = check_ifindex_flags(ifindex, &flags, SD_RESOLVED_NO_TXT|SD_RESOLVED_NO_ADDRESS, error);
+ if (r < 0)
+ return r;
+
+ r = dns_question_new_service(&question_utf8, name, type, domain, !(flags & SD_RESOLVED_NO_TXT), false);
+ if (r < 0)
+ return r;
+
+ r = dns_question_new_service(&question_idna, name, type, domain, !(flags & SD_RESOLVED_NO_TXT), true);
+ if (r < 0)
+ return r;
+
+ r = dns_query_new(m, &q, question_utf8, question_idna, ifindex, flags|SD_RESOLVED_NO_SEARCH);
+ if (r < 0)
+ return r;
+
+ q->request = sd_bus_message_ref(message);
+ q->request_family = family;
+ q->complete = bus_method_resolve_service_complete;
+
+ r = dns_query_bus_track(q, message);
+ if (r < 0)
+ goto fail;
+
+ r = dns_query_go(q);
+ if (r < 0)
+ goto fail;
+
+ return 1;
+
+fail:
+ dns_query_free(q);
+ return r;
+}
+
+int bus_dns_server_append(sd_bus_message *reply, DnsServer *s, bool with_ifindex) {
+ int r;
+
+ assert(reply);
+ assert(s);
+
+ r = sd_bus_message_open_container(reply, 'r', with_ifindex ? "iiay" : "iay");
+ if (r < 0)
+ return r;
+
+ if (with_ifindex) {
+ r = sd_bus_message_append(reply, "i", dns_server_ifindex(s));
+ if (r < 0)
+ return r;
+ }
+
+ r = sd_bus_message_append(reply, "i", s->family);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_append_array(reply, 'y', &s->address, FAMILY_ADDRESS_SIZE(s->family));
+ if (r < 0)
+ return r;
+
+ return sd_bus_message_close_container(reply);
+}
+
+static int bus_property_get_dns_servers(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Manager *m = userdata;
+ unsigned c = 0;
+ DnsServer *s;
+ Iterator i;
+ Link *l;
+ int r;
+
+ assert(reply);
+ assert(m);
+
+ r = sd_bus_message_open_container(reply, 'a', "(iiay)");
+ if (r < 0)
+ return r;
+
+ LIST_FOREACH(servers, s, m->dns_servers) {
+ r = bus_dns_server_append(reply, s, true);
+ if (r < 0)
+ return r;
+
+ c++;
+ }
+
+ HASHMAP_FOREACH(l, m->links, i) {
+ LIST_FOREACH(servers, s, l->dns_servers) {
+ r = bus_dns_server_append(reply, s, true);
+ if (r < 0)
+ return r;
+ c++;
+ }
+ }
+
+ if (c == 0) {
+ LIST_FOREACH(servers, s, m->fallback_dns_servers) {
+ r = bus_dns_server_append(reply, s, true);
+ if (r < 0)
+ return r;
+ }
+ }
+
+ return sd_bus_message_close_container(reply);
+}
+
+static int bus_property_get_domains(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Manager *m = userdata;
+ DnsSearchDomain *d;
+ Iterator i;
+ Link *l;
+ int r;
+
+ assert(reply);
+ assert(m);
+
+ r = sd_bus_message_open_container(reply, 'a', "(isb)");
+ if (r < 0)
+ return r;
+
+ LIST_FOREACH(domains, d, m->search_domains) {
+ r = sd_bus_message_append(reply, "(isb)", 0, d->name, d->route_only);
+ if (r < 0)
+ return r;
+ }
+
+ HASHMAP_FOREACH(l, m->links, i) {
+ LIST_FOREACH(domains, d, l->search_domains) {
+ r = sd_bus_message_append(reply, "(isb)", l->ifindex, d->name, d->route_only);
+ if (r < 0)
+ return r;
+ }
+ }
+
+ return sd_bus_message_close_container(reply);
+}
+
+static int bus_property_get_transaction_statistics(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Manager *m = userdata;
+
+ assert(reply);
+ assert(m);
+
+ return sd_bus_message_append(reply, "(tt)",
+ (uint64_t) hashmap_size(m->dns_transactions),
+ (uint64_t) m->n_transactions_total);
+}
+
+static int bus_property_get_cache_statistics(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ uint64_t size = 0, hit = 0, miss = 0;
+ Manager *m = userdata;
+ DnsScope *s;
+
+ assert(reply);
+ assert(m);
+
+ LIST_FOREACH(scopes, s, m->dns_scopes) {
+ size += dns_cache_size(&s->cache);
+ hit += s->cache.n_hit;
+ miss += s->cache.n_miss;
+ }
+
+ return sd_bus_message_append(reply, "(ttt)", size, hit, miss);
+}
+
+static int bus_property_get_dnssec_statistics(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Manager *m = userdata;
+
+ assert(reply);
+ assert(m);
+
+ return sd_bus_message_append(reply, "(tttt)",
+ (uint64_t) m->n_dnssec_verdict[DNSSEC_SECURE],
+ (uint64_t) m->n_dnssec_verdict[DNSSEC_INSECURE],
+ (uint64_t) m->n_dnssec_verdict[DNSSEC_BOGUS],
+ (uint64_t) m->n_dnssec_verdict[DNSSEC_INDETERMINATE]);
+}
+
+static int bus_property_get_dnssec_supported(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Manager *m = userdata;
+
+ assert(reply);
+ assert(m);
+
+ return sd_bus_message_append(reply, "b", manager_dnssec_supported(m));
+}
+
+static int bus_property_get_ntas(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Manager *m = userdata;
+ const char *domain;
+ Iterator i;
+ int r;
+
+ assert(reply);
+ assert(m);
+
+ r = sd_bus_message_open_container(reply, 'a', "s");
+ if (r < 0)
+ return r;
+
+ SET_FOREACH(domain, m->trust_anchor.negative_by_name, i) {
+ r = sd_bus_message_append(reply, "s", domain);
+ if (r < 0)
+ return r;
+ }
+
+ return sd_bus_message_close_container(reply);
+}
+
+static int bus_method_reset_statistics(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ Manager *m = userdata;
+ DnsScope *s;
+
+ assert(message);
+ assert(m);
+
+ LIST_FOREACH(scopes, s, m->dns_scopes)
+ s->cache.n_hit = s->cache.n_miss = 0;
+
+ m->n_transactions_total = 0;
+ zero(m->n_dnssec_verdict);
+
+ return sd_bus_reply_method_return(message, NULL);
+}
+
+static int get_any_link(Manager *m, int ifindex, Link **ret, sd_bus_error *error) {
+ Link *l;
+
+ assert(m);
+ assert(ret);
+
+ if (ifindex <= 0)
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid interface index");
+
+ l = hashmap_get(m->links, INT_TO_PTR(ifindex));
+ if (!l)
+ return sd_bus_error_setf(error, BUS_ERROR_NO_SUCH_LINK, "Link %i not known", ifindex);
+
+ *ret = l;
+ return 0;
+}
+
+static int call_link_method(Manager *m, sd_bus_message *message, sd_bus_message_handler_t handler, sd_bus_error *error) {
+ int ifindex, r;
+ Link *l;
+
+ assert(m);
+ assert(message);
+ assert(handler);
+
+ assert_cc(sizeof(int) == sizeof(int32_t));
+ r = sd_bus_message_read(message, "i", &ifindex);
+ if (r < 0)
+ return r;
+
+ r = get_any_link(m, ifindex, &l, error);
+ if (r < 0)
+ return r;
+
+ return handler(message, l, error);
+}
+
+static int bus_method_set_link_dns_servers(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ return call_link_method(userdata, message, bus_link_method_set_dns_servers, error);
+}
+
+static int bus_method_set_link_domains(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ return call_link_method(userdata, message, bus_link_method_set_domains, error);
+}
+
+static int bus_method_set_link_llmnr(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ return call_link_method(userdata, message, bus_link_method_set_llmnr, error);
+}
+
+static int bus_method_set_link_mdns(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ return call_link_method(userdata, message, bus_link_method_set_mdns, error);
+}
+
+static int bus_method_set_link_dnssec(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ return call_link_method(userdata, message, bus_link_method_set_dnssec, error);
+}
+
+static int bus_method_set_link_dnssec_negative_trust_anchors(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ return call_link_method(userdata, message, bus_link_method_set_dnssec_negative_trust_anchors, error);
+}
+
+static int bus_method_revert_link(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ return call_link_method(userdata, message, bus_link_method_revert, error);
+}
+
+static int bus_method_get_link(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ _cleanup_free_ char *p = NULL;
+ Manager *m = userdata;
+ int r, ifindex;
+ Link *l;
+
+ assert(message);
+ assert(m);
+
+ assert_cc(sizeof(int) == sizeof(int32_t));
+ r = sd_bus_message_read(message, "i", &ifindex);
+ if (r < 0)
+ return r;
+
+ r = get_any_link(m, ifindex, &l, error);
+ if (r < 0)
+ return r;
+
+ p = link_bus_path(l);
+ if (!p)
+ return -ENOMEM;
+
+ return sd_bus_reply_method_return(message, "o", p);
+}
+
+static int bus_method_flush_caches(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ Manager *m = userdata;
+
+ assert(message);
+ assert(m);
+
+ manager_flush_caches(m);
+
+ return sd_bus_reply_method_return(message, NULL);
+}
+
+static const sd_bus_vtable resolve_vtable[] = {
+ SD_BUS_VTABLE_START(0),
+ SD_BUS_PROPERTY("LLMNRHostname", "s", NULL, offsetof(Manager, llmnr_hostname), 0),
+ SD_BUS_PROPERTY("DNS", "a(iiay)", bus_property_get_dns_servers, 0, 0),
+ SD_BUS_PROPERTY("Domains", "a(isb)", bus_property_get_domains, 0, 0),
+ SD_BUS_PROPERTY("TransactionStatistics", "(tt)", bus_property_get_transaction_statistics, 0, 0),
+ SD_BUS_PROPERTY("CacheStatistics", "(ttt)", bus_property_get_cache_statistics, 0, 0),
+ SD_BUS_PROPERTY("DNSSECStatistics", "(tttt)", bus_property_get_dnssec_statistics, 0, 0),
+ SD_BUS_PROPERTY("DNSSECSupported", "b", bus_property_get_dnssec_supported, 0, 0),
+ SD_BUS_PROPERTY("DNSSECNegativeTrustAnchors", "as", bus_property_get_ntas, 0, 0),
+
+ SD_BUS_METHOD("ResolveHostname", "isit", "a(iiay)st", bus_method_resolve_hostname, SD_BUS_VTABLE_UNPRIVILEGED),
+ SD_BUS_METHOD("ResolveAddress", "iiayt", "a(is)t", bus_method_resolve_address, SD_BUS_VTABLE_UNPRIVILEGED),
+ SD_BUS_METHOD("ResolveRecord", "isqqt", "a(iqqay)t", bus_method_resolve_record, SD_BUS_VTABLE_UNPRIVILEGED),
+ SD_BUS_METHOD("ResolveService", "isssit", "a(qqqsa(iiay)s)aayssst", bus_method_resolve_service, SD_BUS_VTABLE_UNPRIVILEGED),
+ SD_BUS_METHOD("ResetStatistics", NULL, NULL, bus_method_reset_statistics, 0),
+ SD_BUS_METHOD("FlushCaches", NULL, NULL, bus_method_flush_caches, 0),
+ SD_BUS_METHOD("GetLink", "i", "o", bus_method_get_link, SD_BUS_VTABLE_UNPRIVILEGED),
+ SD_BUS_METHOD("SetLinkDNS", "ia(iay)", NULL, bus_method_set_link_dns_servers, 0),
+ SD_BUS_METHOD("SetLinkDomains", "ia(sb)", NULL, bus_method_set_link_domains, 0),
+ SD_BUS_METHOD("SetLinkLLMNR", "is", NULL, bus_method_set_link_llmnr, 0),
+ SD_BUS_METHOD("SetLinkMulticastDNS", "is", NULL, bus_method_set_link_mdns, 0),
+ SD_BUS_METHOD("SetLinkDNSSEC", "is", NULL, bus_method_set_link_dnssec, 0),
+ SD_BUS_METHOD("SetLinkDNSSECNegativeTrustAnchors", "ias", NULL, bus_method_set_link_dnssec_negative_trust_anchors, 0),
+ SD_BUS_METHOD("RevertLink", "i", NULL, bus_method_revert_link, 0),
+
+ SD_BUS_VTABLE_END,
+};
+
+static int on_bus_retry(sd_event_source *s, usec_t usec, void *userdata) {
+ Manager *m = userdata;
+
+ assert(s);
+ assert(m);
+
+ m->bus_retry_event_source = sd_event_source_unref(m->bus_retry_event_source);
+
+ manager_connect_bus(m);
+ return 0;
+}
+
+static int match_prepare_for_sleep(sd_bus_message *message, void *userdata, sd_bus_error *ret_error) {
+ Manager *m = userdata;
+ int b, r;
+
+ assert(message);
+ assert(m);
+
+ r = sd_bus_message_read(message, "b", &b);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to parse PrepareForSleep signal: %m");
+ return 0;
+ }
+
+ if (b)
+ return 0;
+
+ log_debug("Coming back from suspend, verifying all RRs...");
+
+ manager_verify_all(m);
+ return 0;
+}
+
+int manager_connect_bus(Manager *m) {
+ int r;
+
+ assert(m);
+
+ if (m->bus)
+ return 0;
+
+ r = sd_bus_default_system(&m->bus);
+ if (r < 0) {
+ /* We failed to connect? Yuck, we must be in early
+ * boot. Let's try in 5s again. As soon as we have
+ * kdbus we can stop doing this... */
+
+ log_debug_errno(r, "Failed to connect to bus, trying again in 5s: %m");
+
+ r = sd_event_add_time(m->event, &m->bus_retry_event_source, CLOCK_MONOTONIC, now(CLOCK_MONOTONIC) + 5*USEC_PER_SEC, 0, on_bus_retry, m);
+ if (r < 0)
+ return log_error_errno(r, "Failed to install bus reconnect time event: %m");
+
+ (void) sd_event_source_set_description(m->bus_retry_event_source, "bus-retry");
+ return 0;
+ }
+
+ r = sd_bus_add_object_vtable(m->bus, NULL, "/org/freedesktop/resolve1", "org.freedesktop.resolve1.Manager", resolve_vtable, m);
+ if (r < 0)
+ return log_error_errno(r, "Failed to register object: %m");
+
+ r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/resolve1/link", "org.freedesktop.resolve1.Link", link_vtable, link_object_find, m);
+ if (r < 0)
+ return log_error_errno(r, "Failed to register link objects: %m");
+
+ r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/resolve1/link", link_node_enumerator, m);
+ if (r < 0)
+ return log_error_errno(r, "Failed to register link enumerator: %m");
+
+ r = sd_bus_request_name(m->bus, "org.freedesktop.resolve1", 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to register name: %m");
+
+ r = sd_bus_attach_event(m->bus, m->event, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to attach bus to event loop: %m");
+
+ r = sd_bus_add_match(m->bus, &m->prepare_for_sleep_slot,
+ "type='signal',"
+ "sender='org.freedesktop.login1',"
+ "interface='org.freedesktop.login1.Manager',"
+ "member='PrepareForSleep',"
+ "path='/org/freedesktop/login1'",
+ match_prepare_for_sleep,
+ m);
+ if (r < 0)
+ log_error_errno(r, "Failed to add match for PrepareForSleep: %m");
+
+ return 0;
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-bus.h b/src/grp-resolve/systemd-resolved/resolved-bus.h
new file mode 100644
index 0000000000..f49e1337d2
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-bus.h
@@ -0,0 +1,25 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "resolved-manager.h"
+
+int manager_connect_bus(Manager *m);
+int bus_dns_server_append(sd_bus_message *reply, DnsServer *s, bool with_ifindex);
diff --git a/src/grp-resolve/systemd-resolved/resolved-conf.c b/src/grp-resolve/systemd-resolved/resolved-conf.c
new file mode 100644
index 0000000000..49667ec128
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-conf.c
@@ -0,0 +1,241 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Tom Gundersen <teg@jklm.no>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+ ***/
+
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/def.h"
+#include "systemd-basic/extract-word.h"
+#include "systemd-basic/parse-util.h"
+#include "systemd-basic/string-util.h"
+#include "systemd-shared/conf-parser.h"
+
+#include "resolved-conf.h"
+
+int manager_add_dns_server_by_string(Manager *m, DnsServerType type, const char *word) {
+ union in_addr_union address;
+ int family, r, ifindex = 0;
+ DnsServer *s;
+
+ assert(m);
+ assert(word);
+
+ r = in_addr_ifindex_from_string_auto(word, &family, &address, &ifindex);
+ if (r < 0)
+ return r;
+
+ /* Silently filter out 0.0.0.0 and 127.0.0.53 (our own stub DNS listener) */
+ if (!dns_server_address_valid(family, &address))
+ return 0;
+
+ /* Filter out duplicates */
+ s = dns_server_find(manager_get_first_dns_server(m, type), family, &address, ifindex);
+ if (s) {
+ /*
+ * Drop the marker. This is used to find the servers
+ * that ceased to exist, see
+ * manager_mark_dns_servers() and
+ * manager_flush_marked_dns_servers().
+ */
+ dns_server_move_back_and_unmark(s);
+ return 0;
+ }
+
+ return dns_server_new(m, NULL, type, NULL, family, &address, ifindex);
+}
+
+int manager_parse_dns_server_string_and_warn(Manager *m, DnsServerType type, const char *string) {
+ int r;
+
+ assert(m);
+ assert(string);
+
+ for (;;) {
+ _cleanup_free_ char *word = NULL;
+
+ r = extract_first_word(&string, &word, NULL, 0);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ break;
+
+ r = manager_add_dns_server_by_string(m, type, word);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add DNS server address '%s', ignoring: %m", word);
+ }
+
+ return 0;
+}
+
+int manager_add_search_domain_by_string(Manager *m, const char *domain) {
+ DnsSearchDomain *d;
+ bool route_only;
+ int r;
+
+ assert(m);
+ assert(domain);
+
+ route_only = *domain == '~';
+ if (route_only)
+ domain++;
+
+ if (dns_name_is_root(domain) || streq(domain, "*")) {
+ route_only = true;
+ domain = ".";
+ }
+
+ r = dns_search_domain_find(m->search_domains, domain, &d);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ dns_search_domain_move_back_and_unmark(d);
+ else {
+ r = dns_search_domain_new(m, &d, DNS_SEARCH_DOMAIN_SYSTEM, NULL, domain);
+ if (r < 0)
+ return r;
+ }
+
+ d->route_only = route_only;
+ return 0;
+}
+
+int manager_parse_search_domains_and_warn(Manager *m, const char *string) {
+ int r;
+
+ assert(m);
+ assert(string);
+
+ for (;;) {
+ _cleanup_free_ char *word = NULL;
+
+ r = extract_first_word(&string, &word, NULL, EXTRACT_QUOTES);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ break;
+
+ r = manager_add_search_domain_by_string(m, word);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add search domain '%s', ignoring: %m", word);
+ }
+
+ return 0;
+}
+
+int config_parse_dns_servers(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Manager *m = userdata;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(m);
+
+ if (isempty(rvalue))
+ /* Empty assignment means clear the list */
+ dns_server_unlink_all(manager_get_first_dns_server(m, ltype));
+ else {
+ /* Otherwise, add to the list */
+ r = manager_parse_dns_server_string_and_warn(m, ltype, rvalue);
+ if (r < 0) {
+ log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse DNS server string '%s'. Ignoring.", rvalue);
+ return 0;
+ }
+ }
+
+ /* If we have a manual setting, then we stop reading
+ * /etc/resolv.conf */
+ if (ltype == DNS_SERVER_SYSTEM)
+ m->read_resolv_conf = false;
+ if (ltype == DNS_SERVER_FALLBACK)
+ m->need_builtin_fallbacks = false;
+
+ return 0;
+}
+
+int config_parse_search_domains(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Manager *m = userdata;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(m);
+
+ if (isempty(rvalue))
+ /* Empty assignment means clear the list */
+ dns_search_domain_unlink_all(m->search_domains);
+ else {
+ /* Otherwise, add to the list */
+ r = manager_parse_search_domains_and_warn(m, rvalue);
+ if (r < 0) {
+ log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse search domains string '%s'. Ignoring.", rvalue);
+ return 0;
+ }
+ }
+
+ /* If we have a manual setting, then we stop reading
+ * /etc/resolv.conf */
+ m->read_resolv_conf = false;
+
+ return 0;
+}
+
+int manager_parse_config_file(Manager *m) {
+ int r;
+
+ assert(m);
+
+ r = config_parse_many(PKGSYSCONFDIR "/resolved.conf",
+ CONF_PATHS_NULSTR("systemd/resolved.conf.d"),
+ "Resolve\0",
+ config_item_perf_lookup, resolved_gperf_lookup,
+ false, m);
+ if (r < 0)
+ return r;
+
+ if (m->need_builtin_fallbacks) {
+ r = manager_parse_dns_server_string_and_warn(m, DNS_SERVER_FALLBACK, DNS_SERVERS);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-conf.h b/src/grp-resolve/systemd-resolved/resolved-conf.h
new file mode 100644
index 0000000000..e1fd2cceec
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-conf.h
@@ -0,0 +1,36 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Tom Gundersen <teg@jklm.no>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "resolved-manager.h"
+
+int manager_parse_config_file(Manager *m);
+
+int manager_add_search_domain_by_string(Manager *m, const char *domain);
+int manager_parse_search_domains_and_warn(Manager *m, const char *string);
+
+int manager_add_dns_server_by_string(Manager *m, DnsServerType type, const char *word);
+int manager_parse_dns_server_string_and_warn(Manager *m, DnsServerType type, const char *string);
+
+const struct ConfigPerfItem* resolved_gperf_lookup(const char *key, unsigned length);
+
+int config_parse_dns_servers(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
+int config_parse_search_domains(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
+int config_parse_dnssec(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-cache.c b/src/grp-resolve/systemd-resolved/resolved-dns-cache.c
new file mode 100644
index 0000000000..1f8811c5de
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-cache.c
@@ -0,0 +1,1065 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <net/if.h>
+
+#include "basic-dns/resolved-dns-answer.h"
+#include "basic-dns/resolved-dns-packet.h"
+#include "systemd-basic/af-list.h"
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/string-util.h"
+#include "systemd-shared/dns-domain.h"
+
+#include "resolved-dns-cache.h"
+
+/* Never cache more than 4K entries. RFC 1536, Section 5 suggests to
+ * leave DNS caches unbounded, but that's crazy. */
+#define CACHE_MAX 4096
+
+/* We never keep any item longer than 2h in our cache */
+#define CACHE_TTL_MAX_USEC (2 * USEC_PER_HOUR)
+
+typedef enum DnsCacheItemType DnsCacheItemType;
+typedef struct DnsCacheItem DnsCacheItem;
+
+enum DnsCacheItemType {
+ DNS_CACHE_POSITIVE,
+ DNS_CACHE_NODATA,
+ DNS_CACHE_NXDOMAIN,
+};
+
+struct DnsCacheItem {
+ DnsCacheItemType type;
+ DnsResourceKey *key;
+ DnsResourceRecord *rr;
+
+ usec_t until;
+ bool authenticated:1;
+ bool shared_owner:1;
+
+ int ifindex;
+ int owner_family;
+ union in_addr_union owner_address;
+
+ unsigned prioq_idx;
+ LIST_FIELDS(DnsCacheItem, by_key);
+};
+
+static void dns_cache_item_free(DnsCacheItem *i) {
+ if (!i)
+ return;
+
+ dns_resource_record_unref(i->rr);
+ dns_resource_key_unref(i->key);
+ free(i);
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(DnsCacheItem*, dns_cache_item_free);
+
+static void dns_cache_item_unlink_and_free(DnsCache *c, DnsCacheItem *i) {
+ DnsCacheItem *first;
+
+ assert(c);
+
+ if (!i)
+ return;
+
+ first = hashmap_get(c->by_key, i->key);
+ LIST_REMOVE(by_key, first, i);
+
+ if (first)
+ assert_se(hashmap_replace(c->by_key, first->key, first) >= 0);
+ else
+ hashmap_remove(c->by_key, i->key);
+
+ prioq_remove(c->by_expiry, i, &i->prioq_idx);
+
+ dns_cache_item_free(i);
+}
+
+static bool dns_cache_remove_by_rr(DnsCache *c, DnsResourceRecord *rr) {
+ DnsCacheItem *first, *i;
+ int r;
+
+ first = hashmap_get(c->by_key, rr->key);
+ LIST_FOREACH(by_key, i, first) {
+ r = dns_resource_record_equal(i->rr, rr);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ dns_cache_item_unlink_and_free(c, i);
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static bool dns_cache_remove_by_key(DnsCache *c, DnsResourceKey *key) {
+ DnsCacheItem *first, *i, *n;
+
+ assert(c);
+ assert(key);
+
+ first = hashmap_remove(c->by_key, key);
+ if (!first)
+ return false;
+
+ LIST_FOREACH_SAFE(by_key, i, n, first) {
+ prioq_remove(c->by_expiry, i, &i->prioq_idx);
+ dns_cache_item_free(i);
+ }
+
+ return true;
+}
+
+void dns_cache_flush(DnsCache *c) {
+ DnsResourceKey *key;
+
+ assert(c);
+
+ while ((key = hashmap_first_key(c->by_key)))
+ dns_cache_remove_by_key(c, key);
+
+ assert(hashmap_size(c->by_key) == 0);
+ assert(prioq_size(c->by_expiry) == 0);
+
+ c->by_key = hashmap_free(c->by_key);
+ c->by_expiry = prioq_free(c->by_expiry);
+}
+
+static void dns_cache_make_space(DnsCache *c, unsigned add) {
+ assert(c);
+
+ if (add <= 0)
+ return;
+
+ /* Makes space for n new entries. Note that we actually allow
+ * the cache to grow beyond CACHE_MAX, but only when we shall
+ * add more RRs to the cache than CACHE_MAX at once. In that
+ * case the cache will be emptied completely otherwise. */
+
+ for (;;) {
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+ DnsCacheItem *i;
+
+ if (prioq_size(c->by_expiry) <= 0)
+ break;
+
+ if (prioq_size(c->by_expiry) + add < CACHE_MAX)
+ break;
+
+ i = prioq_peek(c->by_expiry);
+ assert(i);
+
+ /* Take an extra reference to the key so that it
+ * doesn't go away in the middle of the remove call */
+ key = dns_resource_key_ref(i->key);
+ dns_cache_remove_by_key(c, key);
+ }
+}
+
+void dns_cache_prune(DnsCache *c) {
+ usec_t t = 0;
+
+ assert(c);
+
+ /* Remove all entries that are past their TTL */
+
+ for (;;) {
+ DnsCacheItem *i;
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
+
+ i = prioq_peek(c->by_expiry);
+ if (!i)
+ break;
+
+ if (t <= 0)
+ t = now(clock_boottime_or_monotonic());
+
+ if (i->until > t)
+ break;
+
+ /* Depending whether this is an mDNS shared entry
+ * either remove only this one RR or the whole RRset */
+ log_debug("Removing %scache entry for %s (expired "USEC_FMT"s ago)",
+ i->shared_owner ? "shared " : "",
+ dns_resource_key_to_string(i->key, key_str, sizeof key_str),
+ (t - i->until) / USEC_PER_SEC);
+
+ if (i->shared_owner)
+ dns_cache_item_unlink_and_free(c, i);
+ else {
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+ /* Take an extra reference to the key so that it
+ * doesn't go away in the middle of the remove call */
+ key = dns_resource_key_ref(i->key);
+ dns_cache_remove_by_key(c, key);
+ }
+ }
+}
+
+static int dns_cache_item_prioq_compare_func(const void *a, const void *b) {
+ const DnsCacheItem *x = a, *y = b;
+
+ if (x->until < y->until)
+ return -1;
+ if (x->until > y->until)
+ return 1;
+ return 0;
+}
+
+static int dns_cache_init(DnsCache *c) {
+ int r;
+
+ assert(c);
+
+ r = prioq_ensure_allocated(&c->by_expiry, dns_cache_item_prioq_compare_func);
+ if (r < 0)
+ return r;
+
+ r = hashmap_ensure_allocated(&c->by_key, &dns_resource_key_hash_ops);
+ if (r < 0)
+ return r;
+
+ return r;
+}
+
+static int dns_cache_link_item(DnsCache *c, DnsCacheItem *i) {
+ DnsCacheItem *first;
+ int r;
+
+ assert(c);
+ assert(i);
+
+ r = prioq_put(c->by_expiry, i, &i->prioq_idx);
+ if (r < 0)
+ return r;
+
+ first = hashmap_get(c->by_key, i->key);
+ if (first) {
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *k = NULL;
+
+ /* Keep a reference to the original key, while we manipulate the list. */
+ k = dns_resource_key_ref(first->key);
+
+ /* Now, try to reduce the number of keys we keep */
+ dns_resource_key_reduce(&first->key, &i->key);
+
+ if (first->rr)
+ dns_resource_key_reduce(&first->rr->key, &i->key);
+ if (i->rr)
+ dns_resource_key_reduce(&i->rr->key, &i->key);
+
+ LIST_PREPEND(by_key, first, i);
+ assert_se(hashmap_replace(c->by_key, first->key, first) >= 0);
+ } else {
+ r = hashmap_put(c->by_key, i->key, i);
+ if (r < 0) {
+ prioq_remove(c->by_expiry, i, &i->prioq_idx);
+ return r;
+ }
+ }
+
+ return 0;
+}
+
+static DnsCacheItem* dns_cache_get(DnsCache *c, DnsResourceRecord *rr) {
+ DnsCacheItem *i;
+
+ assert(c);
+ assert(rr);
+
+ LIST_FOREACH(by_key, i, hashmap_get(c->by_key, rr->key))
+ if (i->rr && dns_resource_record_equal(i->rr, rr) > 0)
+ return i;
+
+ return NULL;
+}
+
+static usec_t calculate_until(DnsResourceRecord *rr, uint32_t nsec_ttl, usec_t timestamp, bool use_soa_minimum) {
+ uint32_t ttl;
+ usec_t u;
+
+ assert(rr);
+
+ ttl = MIN(rr->ttl, nsec_ttl);
+ if (rr->key->type == DNS_TYPE_SOA && use_soa_minimum) {
+ /* If this is a SOA RR, and it is requested, clamp to
+ * the SOA's minimum field. This is used when we do
+ * negative caching, to determine the TTL for the
+ * negative caching entry. See RFC 2308, Section
+ * 5. */
+
+ if (ttl > rr->soa.minimum)
+ ttl = rr->soa.minimum;
+ }
+
+ u = ttl * USEC_PER_SEC;
+ if (u > CACHE_TTL_MAX_USEC)
+ u = CACHE_TTL_MAX_USEC;
+
+ if (rr->expiry != USEC_INFINITY) {
+ usec_t left;
+
+ /* Make use of the DNSSEC RRSIG expiry info, if we
+ * have it */
+
+ left = LESS_BY(rr->expiry, now(CLOCK_REALTIME));
+ if (u > left)
+ u = left;
+ }
+
+ return timestamp + u;
+}
+
+static void dns_cache_item_update_positive(
+ DnsCache *c,
+ DnsCacheItem *i,
+ DnsResourceRecord *rr,
+ bool authenticated,
+ bool shared_owner,
+ usec_t timestamp,
+ int ifindex,
+ int owner_family,
+ const union in_addr_union *owner_address) {
+
+ assert(c);
+ assert(i);
+ assert(rr);
+ assert(owner_address);
+
+ i->type = DNS_CACHE_POSITIVE;
+
+ if (!i->by_key_prev)
+ /* We are the first item in the list, we need to
+ * update the key used in the hashmap */
+
+ assert_se(hashmap_replace(c->by_key, rr->key, i) >= 0);
+
+ dns_resource_record_ref(rr);
+ dns_resource_record_unref(i->rr);
+ i->rr = rr;
+
+ dns_resource_key_unref(i->key);
+ i->key = dns_resource_key_ref(rr->key);
+
+ i->until = calculate_until(rr, (uint32_t) -1, timestamp, false);
+ i->authenticated = authenticated;
+ i->shared_owner = shared_owner;
+
+ i->ifindex = ifindex;
+
+ i->owner_family = owner_family;
+ i->owner_address = *owner_address;
+
+ prioq_reshuffle(c->by_expiry, i, &i->prioq_idx);
+}
+
+static int dns_cache_put_positive(
+ DnsCache *c,
+ DnsResourceRecord *rr,
+ bool authenticated,
+ bool shared_owner,
+ usec_t timestamp,
+ int ifindex,
+ int owner_family,
+ const union in_addr_union *owner_address) {
+
+ _cleanup_(dns_cache_item_freep) DnsCacheItem *i = NULL;
+ DnsCacheItem *existing;
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX], ifname[IF_NAMESIZE];
+ int r, k;
+
+ assert(c);
+ assert(rr);
+ assert(owner_address);
+
+ /* Never cache pseudo RRs */
+ if (dns_class_is_pseudo(rr->key->class))
+ return 0;
+ if (dns_type_is_pseudo(rr->key->type))
+ return 0;
+
+ /* New TTL is 0? Delete this specific entry... */
+ if (rr->ttl <= 0) {
+ k = dns_cache_remove_by_rr(c, rr);
+ log_debug("%s: %s",
+ k > 0 ? "Removed zero TTL entry from cache" : "Not caching zero TTL cache entry",
+ dns_resource_key_to_string(rr->key, key_str, sizeof key_str));
+ return 0;
+ }
+
+ /* Entry exists already? Update TTL, timestamp and owner*/
+ existing = dns_cache_get(c, rr);
+ if (existing) {
+ dns_cache_item_update_positive(
+ c,
+ existing,
+ rr,
+ authenticated,
+ shared_owner,
+ timestamp,
+ ifindex,
+ owner_family,
+ owner_address);
+ return 0;
+ }
+
+ /* Otherwise, add the new RR */
+ r = dns_cache_init(c);
+ if (r < 0)
+ return r;
+
+ dns_cache_make_space(c, 1);
+
+ i = new0(DnsCacheItem, 1);
+ if (!i)
+ return -ENOMEM;
+
+ i->type = DNS_CACHE_POSITIVE;
+ i->key = dns_resource_key_ref(rr->key);
+ i->rr = dns_resource_record_ref(rr);
+ i->until = calculate_until(rr, (uint32_t) -1, timestamp, false);
+ i->authenticated = authenticated;
+ i->shared_owner = shared_owner;
+ i->ifindex = ifindex;
+ i->owner_family = owner_family;
+ i->owner_address = *owner_address;
+ i->prioq_idx = PRIOQ_IDX_NULL;
+
+ r = dns_cache_link_item(c, i);
+ if (r < 0)
+ return r;
+
+ if (log_get_max_level() >= LOG_DEBUG) {
+ _cleanup_free_ char *t = NULL;
+
+ (void) in_addr_to_string(i->owner_family, &i->owner_address, &t);
+
+ log_debug("Added positive %s%s cache entry for %s "USEC_FMT"s on %s/%s/%s",
+ i->authenticated ? "authenticated" : "unauthenticated",
+ i->shared_owner ? " shared" : "",
+ dns_resource_key_to_string(i->key, key_str, sizeof key_str),
+ (i->until - timestamp) / USEC_PER_SEC,
+ i->ifindex == 0 ? "*" : strna(if_indextoname(i->ifindex, ifname)),
+ af_to_name_short(i->owner_family),
+ strna(t));
+ }
+
+ i = NULL;
+ return 0;
+}
+
+static int dns_cache_put_negative(
+ DnsCache *c,
+ DnsResourceKey *key,
+ int rcode,
+ bool authenticated,
+ uint32_t nsec_ttl,
+ usec_t timestamp,
+ DnsResourceRecord *soa,
+ int owner_family,
+ const union in_addr_union *owner_address) {
+
+ _cleanup_(dns_cache_item_freep) DnsCacheItem *i = NULL;
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
+ int r;
+
+ assert(c);
+ assert(key);
+ assert(soa);
+ assert(owner_address);
+
+ /* Never cache pseudo RR keys. DNS_TYPE_ANY is particularly
+ * important to filter out as we use this as a pseudo-type for
+ * NXDOMAIN entries */
+ if (dns_class_is_pseudo(key->class))
+ return 0;
+ if (dns_type_is_pseudo(key->type))
+ return 0;
+
+ if (nsec_ttl <= 0 || soa->soa.minimum <= 0 || soa->ttl <= 0) {
+ log_debug("Not caching negative entry with zero SOA/NSEC/NSEC3 TTL: %s",
+ dns_resource_key_to_string(key, key_str, sizeof key_str));
+ return 0;
+ }
+
+ if (!IN_SET(rcode, DNS_RCODE_SUCCESS, DNS_RCODE_NXDOMAIN))
+ return 0;
+
+ r = dns_cache_init(c);
+ if (r < 0)
+ return r;
+
+ dns_cache_make_space(c, 1);
+
+ i = new0(DnsCacheItem, 1);
+ if (!i)
+ return -ENOMEM;
+
+ i->type = rcode == DNS_RCODE_SUCCESS ? DNS_CACHE_NODATA : DNS_CACHE_NXDOMAIN;
+ i->until = calculate_until(soa, nsec_ttl, timestamp, true);
+ i->authenticated = authenticated;
+ i->owner_family = owner_family;
+ i->owner_address = *owner_address;
+ i->prioq_idx = PRIOQ_IDX_NULL;
+
+ if (i->type == DNS_CACHE_NXDOMAIN) {
+ /* NXDOMAIN entries should apply equally to all types, so we use ANY as
+ * a pseudo type for this purpose here. */
+ i->key = dns_resource_key_new(key->class, DNS_TYPE_ANY, dns_resource_key_name(key));
+ if (!i->key)
+ return -ENOMEM;
+
+ /* Make sure to remove any previous entry for this
+ * specific ANY key. (For non-ANY keys the cache data
+ * is already cleared by the caller.) Note that we
+ * don't bother removing positive or NODATA cache
+ * items in this case, because it would either be slow
+ * or require explicit indexing by name */
+ dns_cache_remove_by_key(c, key);
+ } else
+ i->key = dns_resource_key_ref(key);
+
+ r = dns_cache_link_item(c, i);
+ if (r < 0)
+ return r;
+
+ log_debug("Added %s cache entry for %s "USEC_FMT"s",
+ i->type == DNS_CACHE_NODATA ? "NODATA" : "NXDOMAIN",
+ dns_resource_key_to_string(i->key, key_str, sizeof key_str),
+ (i->until - timestamp) / USEC_PER_SEC);
+
+ i = NULL;
+ return 0;
+}
+
+static void dns_cache_remove_previous(
+ DnsCache *c,
+ DnsResourceKey *key,
+ DnsAnswer *answer) {
+
+ DnsResourceRecord *rr;
+ DnsAnswerFlags flags;
+
+ assert(c);
+
+ /* First, if we were passed a key (i.e. on LLMNR/DNS, but
+ * not on mDNS), delete all matching old RRs, so that we only
+ * keep complete by_key in place. */
+ if (key)
+ dns_cache_remove_by_key(c, key);
+
+ /* Second, flush all entries matching the answer, unless this
+ * is an RR that is explicitly marked to be "shared" between
+ * peers (i.e. mDNS RRs without the flush-cache bit set). */
+ DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) {
+ if ((flags & DNS_ANSWER_CACHEABLE) == 0)
+ continue;
+
+ if (flags & DNS_ANSWER_SHARED_OWNER)
+ continue;
+
+ dns_cache_remove_by_key(c, rr->key);
+ }
+}
+
+static bool rr_eligible(DnsResourceRecord *rr) {
+ assert(rr);
+
+ /* When we see an NSEC/NSEC3 RR, we'll only cache it if it is from the lower zone, not the upper zone, since
+ * that's where the interesting bits are (with exception of DS RRs). Of course, this way we cannot derive DS
+ * existence from any cached NSEC/NSEC3, but that should be fine. */
+
+ switch (rr->key->type) {
+
+ case DNS_TYPE_NSEC:
+ return !bitmap_isset(rr->nsec.types, DNS_TYPE_NS) ||
+ bitmap_isset(rr->nsec.types, DNS_TYPE_SOA);
+
+ case DNS_TYPE_NSEC3:
+ return !bitmap_isset(rr->nsec3.types, DNS_TYPE_NS) ||
+ bitmap_isset(rr->nsec3.types, DNS_TYPE_SOA);
+
+ default:
+ return true;
+ }
+}
+
+int dns_cache_put(
+ DnsCache *c,
+ DnsResourceKey *key,
+ int rcode,
+ DnsAnswer *answer,
+ bool authenticated,
+ uint32_t nsec_ttl,
+ usec_t timestamp,
+ int owner_family,
+ const union in_addr_union *owner_address) {
+
+ DnsResourceRecord *soa = NULL, *rr;
+ DnsAnswerFlags flags;
+ unsigned cache_keys;
+ int r, ifindex;
+
+ assert(c);
+ assert(owner_address);
+
+ dns_cache_remove_previous(c, key, answer);
+
+ /* We only care for positive replies and NXDOMAINs, on all
+ * other replies we will simply flush the respective entries,
+ * and that's it */
+ if (!IN_SET(rcode, DNS_RCODE_SUCCESS, DNS_RCODE_NXDOMAIN))
+ return 0;
+
+ if (dns_answer_size(answer) <= 0) {
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
+
+ log_debug("Not caching negative entry without a SOA record: %s",
+ dns_resource_key_to_string(key, key_str, sizeof key_str));
+ return 0;
+ }
+
+ cache_keys = dns_answer_size(answer);
+ if (key)
+ cache_keys++;
+
+ /* Make some space for our new entries */
+ dns_cache_make_space(c, cache_keys);
+
+ if (timestamp <= 0)
+ timestamp = now(clock_boottime_or_monotonic());
+
+ /* Second, add in positive entries for all contained RRs */
+ DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, answer) {
+ if ((flags & DNS_ANSWER_CACHEABLE) == 0)
+ continue;
+
+ r = rr_eligible(rr);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ r = dns_cache_put_positive(
+ c,
+ rr,
+ flags & DNS_ANSWER_AUTHENTICATED,
+ flags & DNS_ANSWER_SHARED_OWNER,
+ timestamp,
+ ifindex,
+ owner_family, owner_address);
+ if (r < 0)
+ goto fail;
+ }
+
+ if (!key) /* mDNS doesn't know negative caching, really */
+ return 0;
+
+ /* Third, add in negative entries if the key has no RR */
+ r = dns_answer_match_key(answer, key, NULL);
+ if (r < 0)
+ goto fail;
+ if (r > 0)
+ return 0;
+
+ /* But not if it has a matching CNAME/DNAME (the negative
+ * caching will be done on the canonical name, not on the
+ * alias) */
+ r = dns_answer_find_cname_or_dname(answer, key, NULL, NULL);
+ if (r < 0)
+ goto fail;
+ if (r > 0)
+ return 0;
+
+ /* See https://tools.ietf.org/html/rfc2308, which say that a
+ * matching SOA record in the packet is used to enable
+ * negative caching. */
+ r = dns_answer_find_soa(answer, key, &soa, &flags);
+ if (r < 0)
+ goto fail;
+ if (r == 0)
+ return 0;
+
+ /* Refuse using the SOA data if it is unsigned, but the key is
+ * signed */
+ if (authenticated && (flags & DNS_ANSWER_AUTHENTICATED) == 0)
+ return 0;
+
+ r = dns_cache_put_negative(
+ c,
+ key,
+ rcode,
+ authenticated,
+ nsec_ttl,
+ timestamp,
+ soa,
+ owner_family, owner_address);
+ if (r < 0)
+ goto fail;
+
+ return 0;
+
+fail:
+ /* Adding all RRs failed. Let's clean up what we already
+ * added, just in case */
+
+ if (key)
+ dns_cache_remove_by_key(c, key);
+
+ DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) {
+ if ((flags & DNS_ANSWER_CACHEABLE) == 0)
+ continue;
+
+ dns_cache_remove_by_key(c, rr->key);
+ }
+
+ return r;
+}
+
+static DnsCacheItem *dns_cache_get_by_key_follow_cname_dname_nsec(DnsCache *c, DnsResourceKey *k) {
+ DnsCacheItem *i;
+ const char *n;
+ int r;
+
+ assert(c);
+ assert(k);
+
+ /* If we hit some OOM error, or suchlike, we don't care too
+ * much, after all this is just a cache */
+
+ i = hashmap_get(c->by_key, k);
+ if (i)
+ return i;
+
+ n = dns_resource_key_name(k);
+
+ /* Check if we have an NXDOMAIN cache item for the name, notice that we use
+ * the pseudo-type ANY for NXDOMAIN cache items. */
+ i = hashmap_get(c->by_key, &DNS_RESOURCE_KEY_CONST(k->class, DNS_TYPE_ANY, n));
+ if (i && i->type == DNS_CACHE_NXDOMAIN)
+ return i;
+
+ if (dns_type_may_redirect(k->type)) {
+ /* Check if we have a CNAME record instead */
+ i = hashmap_get(c->by_key, &DNS_RESOURCE_KEY_CONST(k->class, DNS_TYPE_CNAME, n));
+ if (i)
+ return i;
+
+ /* OK, let's look for cached DNAME records. */
+ for (;;) {
+ if (isempty(n))
+ return NULL;
+
+ i = hashmap_get(c->by_key, &DNS_RESOURCE_KEY_CONST(k->class, DNS_TYPE_DNAME, n));
+ if (i)
+ return i;
+
+ /* Jump one label ahead */
+ r = dns_name_parent(&n);
+ if (r <= 0)
+ return NULL;
+ }
+ }
+
+ if (k->type != DNS_TYPE_NSEC) {
+ /* Check if we have an NSEC record instead for the name. */
+ i = hashmap_get(c->by_key, &DNS_RESOURCE_KEY_CONST(k->class, DNS_TYPE_NSEC, n));
+ if (i)
+ return i;
+ }
+
+ return NULL;
+}
+
+int dns_cache_lookup(DnsCache *c, DnsResourceKey *key, bool clamp_ttl, int *rcode, DnsAnswer **ret, bool *authenticated) {
+ _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
+ unsigned n = 0;
+ int r;
+ bool nxdomain = false;
+ DnsCacheItem *j, *first, *nsec = NULL;
+ bool have_authenticated = false, have_non_authenticated = false;
+ usec_t current;
+
+ assert(c);
+ assert(key);
+ assert(rcode);
+ assert(ret);
+ assert(authenticated);
+
+ if (key->type == DNS_TYPE_ANY || key->class == DNS_CLASS_ANY) {
+ /* If we have ANY lookups we don't use the cache, so
+ * that the caller refreshes via the network. */
+
+ log_debug("Ignoring cache for ANY lookup: %s",
+ dns_resource_key_to_string(key, key_str, sizeof key_str));
+
+ c->n_miss++;
+
+ *ret = NULL;
+ *rcode = DNS_RCODE_SUCCESS;
+ return 0;
+ }
+
+ first = dns_cache_get_by_key_follow_cname_dname_nsec(c, key);
+ if (!first) {
+ /* If one question cannot be answered we need to refresh */
+
+ log_debug("Cache miss for %s",
+ dns_resource_key_to_string(key, key_str, sizeof key_str));
+
+ c->n_miss++;
+
+ *ret = NULL;
+ *rcode = DNS_RCODE_SUCCESS;
+ return 0;
+ }
+
+ LIST_FOREACH(by_key, j, first) {
+ if (j->rr) {
+ if (j->rr->key->type == DNS_TYPE_NSEC)
+ nsec = j;
+
+ n++;
+ } else if (j->type == DNS_CACHE_NXDOMAIN)
+ nxdomain = true;
+
+ if (j->authenticated)
+ have_authenticated = true;
+ else
+ have_non_authenticated = true;
+ }
+
+ if (nsec && !IN_SET(key->type, DNS_TYPE_NSEC, DNS_TYPE_DS)) {
+ /* Note that we won't derive information for DS RRs from an NSEC, because we only cache NSEC RRs from
+ * the lower-zone of a zone cut, but the DS RRs are on the upper zone. */
+
+ log_debug("NSEC NODATA cache hit for %s",
+ dns_resource_key_to_string(key, key_str, sizeof key_str));
+
+ /* We only found an NSEC record that matches our name.
+ * If it says the type doesn't exist report
+ * NODATA. Otherwise report a cache miss. */
+
+ *ret = NULL;
+ *rcode = DNS_RCODE_SUCCESS;
+ *authenticated = nsec->authenticated;
+
+ if (!bitmap_isset(nsec->rr->nsec.types, key->type) &&
+ !bitmap_isset(nsec->rr->nsec.types, DNS_TYPE_CNAME) &&
+ !bitmap_isset(nsec->rr->nsec.types, DNS_TYPE_DNAME)) {
+ c->n_hit++;
+ return 1;
+ }
+
+ c->n_miss++;
+ return 0;
+ }
+
+ log_debug("%s cache hit for %s",
+ n > 0 ? "Positive" :
+ nxdomain ? "NXDOMAIN" : "NODATA",
+ dns_resource_key_to_string(key, key_str, sizeof key_str));
+
+ if (n <= 0) {
+ c->n_hit++;
+
+ *ret = NULL;
+ *rcode = nxdomain ? DNS_RCODE_NXDOMAIN : DNS_RCODE_SUCCESS;
+ *authenticated = have_authenticated && !have_non_authenticated;
+ return 1;
+ }
+
+ answer = dns_answer_new(n);
+ if (!answer)
+ return -ENOMEM;
+
+ if (clamp_ttl)
+ current = now(clock_boottime_or_monotonic());
+
+ LIST_FOREACH(by_key, j, first) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+ if (!j->rr)
+ continue;
+
+ if (clamp_ttl) {
+ rr = dns_resource_record_ref(j->rr);
+
+ r = dns_resource_record_clamp_ttl(&rr, LESS_BY(j->until, current) / USEC_PER_SEC);
+ if (r < 0)
+ return r;
+ }
+
+ r = dns_answer_add(answer, rr ?: j->rr, j->ifindex, j->authenticated ? DNS_ANSWER_AUTHENTICATED : 0);
+ if (r < 0)
+ return r;
+ }
+
+ c->n_hit++;
+
+ *ret = answer;
+ *rcode = DNS_RCODE_SUCCESS;
+ *authenticated = have_authenticated && !have_non_authenticated;
+ answer = NULL;
+
+ return n;
+}
+
+int dns_cache_check_conflicts(DnsCache *cache, DnsResourceRecord *rr, int owner_family, const union in_addr_union *owner_address) {
+ DnsCacheItem *i, *first;
+ bool same_owner = true;
+
+ assert(cache);
+ assert(rr);
+
+ dns_cache_prune(cache);
+
+ /* See if there's a cache entry for the same key. If there
+ * isn't there's no conflict */
+ first = hashmap_get(cache->by_key, rr->key);
+ if (!first)
+ return 0;
+
+ /* See if the RR key is owned by the same owner, if so, there
+ * isn't a conflict either */
+ LIST_FOREACH(by_key, i, first) {
+ if (i->owner_family != owner_family ||
+ !in_addr_equal(owner_family, &i->owner_address, owner_address)) {
+ same_owner = false;
+ break;
+ }
+ }
+ if (same_owner)
+ return 0;
+
+ /* See if there's the exact same RR in the cache. If yes, then
+ * there's no conflict. */
+ if (dns_cache_get(cache, rr))
+ return 0;
+
+ /* There's a conflict */
+ return 1;
+}
+
+int dns_cache_export_shared_to_packet(DnsCache *cache, DnsPacket *p) {
+ unsigned ancount = 0;
+ Iterator iterator;
+ DnsCacheItem *i;
+ int r;
+
+ assert(cache);
+ assert(p);
+
+ HASHMAP_FOREACH(i, cache->by_key, iterator) {
+ DnsCacheItem *j;
+
+ LIST_FOREACH(by_key, j, i) {
+ if (!j->rr)
+ continue;
+
+ if (!j->shared_owner)
+ continue;
+
+ r = dns_packet_append_rr(p, j->rr, NULL, NULL);
+ if (r == -EMSGSIZE && p->protocol == DNS_PROTOCOL_MDNS) {
+ /* For mDNS, if we're unable to stuff all known answers into the given packet,
+ * allocate a new one, push the RR into that one and link it to the current one.
+ */
+
+ DNS_PACKET_HEADER(p)->ancount = htobe16(ancount);
+ ancount = 0;
+
+ r = dns_packet_new_query(&p->more, p->protocol, 0, true);
+ if (r < 0)
+ return r;
+
+ /* continue with new packet */
+ p = p->more;
+ r = dns_packet_append_rr(p, j->rr, NULL, NULL);
+ }
+
+ if (r < 0)
+ return r;
+
+ ancount++;
+ }
+ }
+
+ DNS_PACKET_HEADER(p)->ancount = htobe16(ancount);
+
+ return 0;
+}
+
+void dns_cache_dump(DnsCache *cache, FILE *f) {
+ Iterator iterator;
+ DnsCacheItem *i;
+
+ if (!cache)
+ return;
+
+ if (!f)
+ f = stdout;
+
+ HASHMAP_FOREACH(i, cache->by_key, iterator) {
+ DnsCacheItem *j;
+
+ LIST_FOREACH(by_key, j, i) {
+
+ fputc('\t', f);
+
+ if (j->rr) {
+ const char *t;
+ t = dns_resource_record_to_string(j->rr);
+ if (!t) {
+ log_oom();
+ continue;
+ }
+
+ fputs(t, f);
+ fputc('\n', f);
+ } else {
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
+
+ fputs(dns_resource_key_to_string(j->key, key_str, sizeof key_str), f);
+ fputs(" -- ", f);
+ fputs(j->type == DNS_CACHE_NODATA ? "NODATA" : "NXDOMAIN", f);
+ fputc('\n', f);
+ }
+ }
+ }
+}
+
+bool dns_cache_is_empty(DnsCache *cache) {
+ if (!cache)
+ return true;
+
+ return hashmap_isempty(cache->by_key);
+}
+
+unsigned dns_cache_size(DnsCache *cache) {
+ if (!cache)
+ return 0;
+
+ return hashmap_size(cache->by_key);
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-cache.h b/src/grp-resolve/systemd-resolved/resolved-dns-cache.h
new file mode 100644
index 0000000000..c2b6a987b9
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-cache.h
@@ -0,0 +1,52 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "systemd-basic/hashmap.h"
+#include "systemd-basic/list.h"
+#include "systemd-basic/prioq.h"
+#include "systemd-basic/time-util.h"
+
+typedef struct DnsCache {
+ Hashmap *by_key;
+ Prioq *by_expiry;
+ unsigned n_hit;
+ unsigned n_miss;
+} DnsCache;
+
+#include "basic-dns/resolved-dns-answer.h"
+#include "basic-dns/resolved-dns-packet.h"
+#include "basic-dns/resolved-dns-question.h"
+#include "basic-dns/resolved-dns-rr.h"
+
+void dns_cache_flush(DnsCache *c);
+void dns_cache_prune(DnsCache *c);
+
+int dns_cache_put(DnsCache *c, DnsResourceKey *key, int rcode, DnsAnswer *answer, bool authenticated, uint32_t nsec_ttl, usec_t timestamp, int owner_family, const union in_addr_union *owner_address);
+int dns_cache_lookup(DnsCache *c, DnsResourceKey *key, bool clamp_ttl, int *rcode, DnsAnswer **answer, bool *authenticated);
+
+int dns_cache_check_conflicts(DnsCache *cache, DnsResourceRecord *rr, int owner_family, const union in_addr_union *owner_address);
+
+void dns_cache_dump(DnsCache *cache, FILE *f);
+bool dns_cache_is_empty(DnsCache *cache);
+
+unsigned dns_cache_size(DnsCache *cache);
+
+int dns_cache_export_shared_to_packet(DnsCache *cache, DnsPacket *p);
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-query.c b/src/grp-resolve/systemd-resolved/resolved-dns-query.c
new file mode 100644
index 0000000000..7c270ccd2b
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-query.c
@@ -0,0 +1,1122 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "basic-dns/dns-type.h"
+#include "sd-netlink/local-addresses.h"
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/hostname-util.h"
+#include "systemd-basic/string-util.h"
+#include "systemd-shared/dns-domain.h"
+
+#include "resolved-dns-query.h"
+#include "resolved-dns-synthesize.h"
+#include "resolved-etc-hosts.h"
+
+/* How long to wait for the query in total */
+#define QUERY_TIMEOUT_USEC (30 * USEC_PER_SEC)
+
+#define CNAME_MAX 8
+#define QUERIES_MAX 2048
+#define AUXILIARY_QUERIES_MAX 64
+
+static int dns_query_candidate_new(DnsQueryCandidate **ret, DnsQuery *q, DnsScope *s) {
+ DnsQueryCandidate *c;
+
+ assert(ret);
+ assert(q);
+ assert(s);
+
+ c = new0(DnsQueryCandidate, 1);
+ if (!c)
+ return -ENOMEM;
+
+ c->query = q;
+ c->scope = s;
+
+ LIST_PREPEND(candidates_by_query, q->candidates, c);
+ LIST_PREPEND(candidates_by_scope, s->query_candidates, c);
+
+ *ret = c;
+ return 0;
+}
+
+static void dns_query_candidate_stop(DnsQueryCandidate *c) {
+ DnsTransaction *t;
+
+ assert(c);
+
+ while ((t = set_steal_first(c->transactions))) {
+ set_remove(t->notify_query_candidates, c);
+ set_remove(t->notify_query_candidates_done, c);
+ dns_transaction_gc(t);
+ }
+}
+
+DnsQueryCandidate* dns_query_candidate_free(DnsQueryCandidate *c) {
+
+ if (!c)
+ return NULL;
+
+ dns_query_candidate_stop(c);
+
+ set_free(c->transactions);
+ dns_search_domain_unref(c->search_domain);
+
+ if (c->query)
+ LIST_REMOVE(candidates_by_query, c->query->candidates, c);
+
+ if (c->scope)
+ LIST_REMOVE(candidates_by_scope, c->scope->query_candidates, c);
+
+ free(c);
+
+ return NULL;
+}
+
+static int dns_query_candidate_next_search_domain(DnsQueryCandidate *c) {
+ DnsSearchDomain *next = NULL;
+
+ assert(c);
+
+ if (c->search_domain && c->search_domain->linked)
+ next = c->search_domain->domains_next;
+ else
+ next = dns_scope_get_search_domains(c->scope);
+
+ for (;;) {
+ if (!next) /* We hit the end of the list */
+ return 0;
+
+ if (!next->route_only)
+ break;
+
+ /* Skip over route-only domains */
+ next = next->domains_next;
+ }
+
+ dns_search_domain_unref(c->search_domain);
+ c->search_domain = dns_search_domain_ref(next);
+
+ return 1;
+}
+
+static int dns_query_candidate_add_transaction(DnsQueryCandidate *c, DnsResourceKey *key) {
+ DnsTransaction *t;
+ int r;
+
+ assert(c);
+ assert(key);
+
+ t = dns_scope_find_transaction(c->scope, key, true);
+ if (!t) {
+ r = dns_transaction_new(&t, c->scope, key);
+ if (r < 0)
+ return r;
+ } else {
+ if (set_contains(c->transactions, t))
+ return 0;
+ }
+
+ r = set_ensure_allocated(&c->transactions, NULL);
+ if (r < 0)
+ goto gc;
+
+ r = set_ensure_allocated(&t->notify_query_candidates, NULL);
+ if (r < 0)
+ goto gc;
+
+ r = set_ensure_allocated(&t->notify_query_candidates_done, NULL);
+ if (r < 0)
+ goto gc;
+
+ r = set_put(t->notify_query_candidates, c);
+ if (r < 0)
+ goto gc;
+
+ r = set_put(c->transactions, t);
+ if (r < 0) {
+ (void) set_remove(t->notify_query_candidates, c);
+ goto gc;
+ }
+
+ t->clamp_ttl = c->query->clamp_ttl;
+ return 1;
+
+gc:
+ dns_transaction_gc(t);
+ return r;
+}
+
+static int dns_query_candidate_go(DnsQueryCandidate *c) {
+ DnsTransaction *t;
+ Iterator i;
+ int r;
+ unsigned n = 0;
+
+ assert(c);
+
+ /* Start the transactions that are not started yet */
+ SET_FOREACH(t, c->transactions, i) {
+ if (t->state != DNS_TRANSACTION_NULL)
+ continue;
+
+ r = dns_transaction_go(t);
+ if (r < 0)
+ return r;
+
+ n++;
+ }
+
+ /* If there was nothing to start, then let's proceed immediately */
+ if (n == 0)
+ dns_query_candidate_notify(c);
+
+ return 0;
+}
+
+static DnsTransactionState dns_query_candidate_state(DnsQueryCandidate *c) {
+ DnsTransactionState state = DNS_TRANSACTION_NO_SERVERS;
+ DnsTransaction *t;
+ Iterator i;
+
+ assert(c);
+
+ if (c->error_code != 0)
+ return DNS_TRANSACTION_ERRNO;
+
+ SET_FOREACH(t, c->transactions, i) {
+
+ switch (t->state) {
+
+ case DNS_TRANSACTION_NULL:
+ /* If there's a NULL transaction pending, then
+ * this means not all transactions where
+ * started yet, and we were called from within
+ * the stackframe that is supposed to start
+ * remaining transactions. In this case,
+ * simply claim the candidate is pending. */
+
+ case DNS_TRANSACTION_PENDING:
+ case DNS_TRANSACTION_VALIDATING:
+ /* If there's one transaction currently in
+ * VALIDATING state, then this means there's
+ * also one in PENDING state, hence we can
+ * return PENDING immediately. */
+ return DNS_TRANSACTION_PENDING;
+
+ case DNS_TRANSACTION_SUCCESS:
+ state = t->state;
+ break;
+
+ default:
+ if (state != DNS_TRANSACTION_SUCCESS)
+ state = t->state;
+
+ break;
+ }
+ }
+
+ return state;
+}
+
+static bool dns_query_candidate_is_routable(DnsQueryCandidate *c, uint16_t type) {
+ int family;
+
+ assert(c);
+
+ /* Checks whether the specified RR type matches an address family that is routable on the link(s) the scope of
+ * this candidate belongs to. Specifically, whether there's a routable IPv4 address on it if we query an A RR,
+ * or a routable IPv6 address if we query an AAAA RR. */
+
+ if (!c->query->suppress_unroutable_family)
+ return true;
+
+ if (c->scope->protocol != DNS_PROTOCOL_DNS)
+ return true;
+
+ family = dns_type_to_af(type);
+ if (family < 0)
+ return true;
+
+ if (c->scope->link)
+ return link_relevant(c->scope->link, family, false);
+ else
+ return manager_routable(c->scope->manager, family);
+}
+
+static int dns_query_candidate_setup_transactions(DnsQueryCandidate *c) {
+ DnsQuestion *question;
+ DnsResourceKey *key;
+ int n = 0, r;
+
+ assert(c);
+
+ dns_query_candidate_stop(c);
+
+ question = dns_query_question_for_protocol(c->query, c->scope->protocol);
+
+ /* Create one transaction per question key */
+ DNS_QUESTION_FOREACH(key, question) {
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *new_key = NULL;
+ DnsResourceKey *qkey;
+
+ if (!dns_query_candidate_is_routable(c, key->type))
+ continue;
+
+ if (c->search_domain) {
+ r = dns_resource_key_new_append_suffix(&new_key, key, c->search_domain->name);
+ if (r < 0)
+ goto fail;
+
+ qkey = new_key;
+ } else
+ qkey = key;
+
+ if (!dns_scope_good_key(c->scope, qkey))
+ continue;
+
+ r = dns_query_candidate_add_transaction(c, qkey);
+ if (r < 0)
+ goto fail;
+
+ n++;
+ }
+
+ return n;
+
+fail:
+ dns_query_candidate_stop(c);
+ return r;
+}
+
+void dns_query_candidate_notify(DnsQueryCandidate *c) {
+ DnsTransactionState state;
+ int r;
+
+ assert(c);
+
+ state = dns_query_candidate_state(c);
+
+ if (DNS_TRANSACTION_IS_LIVE(state))
+ return;
+
+ if (state != DNS_TRANSACTION_SUCCESS && c->search_domain) {
+
+ r = dns_query_candidate_next_search_domain(c);
+ if (r < 0)
+ goto fail;
+
+ if (r > 0) {
+ /* OK, there's another search domain to try, let's do so. */
+
+ r = dns_query_candidate_setup_transactions(c);
+ if (r < 0)
+ goto fail;
+
+ if (r > 0) {
+ /* New transactions where queued. Start them and wait */
+
+ r = dns_query_candidate_go(c);
+ if (r < 0)
+ goto fail;
+
+ return;
+ }
+ }
+
+ }
+
+ dns_query_ready(c->query);
+ return;
+
+fail:
+ log_warning_errno(r, "Failed to follow search domains: %m");
+ c->error_code = r;
+ dns_query_ready(c->query);
+}
+
+static void dns_query_stop(DnsQuery *q) {
+ DnsQueryCandidate *c;
+
+ assert(q);
+
+ q->timeout_event_source = sd_event_source_unref(q->timeout_event_source);
+
+ LIST_FOREACH(candidates_by_query, c, q->candidates)
+ dns_query_candidate_stop(c);
+}
+
+static void dns_query_free_candidates(DnsQuery *q) {
+ assert(q);
+
+ while (q->candidates)
+ dns_query_candidate_free(q->candidates);
+}
+
+static void dns_query_reset_answer(DnsQuery *q) {
+ assert(q);
+
+ q->answer = dns_answer_unref(q->answer);
+ q->answer_rcode = 0;
+ q->answer_dnssec_result = _DNSSEC_RESULT_INVALID;
+ q->answer_errno = 0;
+ q->answer_authenticated = false;
+ q->answer_protocol = _DNS_PROTOCOL_INVALID;
+ q->answer_family = AF_UNSPEC;
+ q->answer_search_domain = dns_search_domain_unref(q->answer_search_domain);
+}
+
+DnsQuery *dns_query_free(DnsQuery *q) {
+ if (!q)
+ return NULL;
+
+ while (q->auxiliary_queries)
+ dns_query_free(q->auxiliary_queries);
+
+ if (q->auxiliary_for) {
+ assert(q->auxiliary_for->n_auxiliary_queries > 0);
+ q->auxiliary_for->n_auxiliary_queries--;
+ LIST_REMOVE(auxiliary_queries, q->auxiliary_for->auxiliary_queries, q);
+ }
+
+ dns_query_free_candidates(q);
+
+ dns_question_unref(q->question_idna);
+ dns_question_unref(q->question_utf8);
+
+ dns_query_reset_answer(q);
+
+ sd_bus_message_unref(q->request);
+ sd_bus_track_unref(q->bus_track);
+
+ dns_packet_unref(q->request_dns_packet);
+
+ if (q->request_dns_stream) {
+ /* Detach the stream from our query, in case something else keeps a reference to it. */
+ q->request_dns_stream->complete = NULL;
+ q->request_dns_stream->on_packet = NULL;
+ q->request_dns_stream->query = NULL;
+ dns_stream_unref(q->request_dns_stream);
+ }
+
+ free(q->request_address_string);
+
+ if (q->manager) {
+ LIST_REMOVE(queries, q->manager->dns_queries, q);
+ q->manager->n_dns_queries--;
+ }
+
+ free(q);
+
+ return NULL;
+}
+
+int dns_query_new(
+ Manager *m,
+ DnsQuery **ret,
+ DnsQuestion *question_utf8,
+ DnsQuestion *question_idna,
+ int ifindex,
+ uint64_t flags) {
+
+ _cleanup_(dns_query_freep) DnsQuery *q = NULL;
+ DnsResourceKey *key;
+ bool good = false;
+ int r;
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
+
+ assert(m);
+
+ if (dns_question_size(question_utf8) > 0) {
+ r = dns_question_is_valid_for_query(question_utf8);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EINVAL;
+
+ good = true;
+ }
+
+ /* If the IDNA and UTF8 questions are the same, merge their references */
+ r = dns_question_is_equal(question_idna, question_utf8);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ question_idna = question_utf8;
+ else {
+ if (dns_question_size(question_idna) > 0) {
+ r = dns_question_is_valid_for_query(question_idna);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EINVAL;
+
+ good = true;
+ }
+ }
+
+ if (!good) /* don't allow empty queries */
+ return -EINVAL;
+
+ if (m->n_dns_queries >= QUERIES_MAX)
+ return -EBUSY;
+
+ q = new0(DnsQuery, 1);
+ if (!q)
+ return -ENOMEM;
+
+ q->question_utf8 = dns_question_ref(question_utf8);
+ q->question_idna = dns_question_ref(question_idna);
+ q->ifindex = ifindex;
+ q->flags = flags;
+ q->answer_dnssec_result = _DNSSEC_RESULT_INVALID;
+ q->answer_protocol = _DNS_PROTOCOL_INVALID;
+ q->answer_family = AF_UNSPEC;
+
+ /* First dump UTF8 question */
+ DNS_QUESTION_FOREACH(key, question_utf8)
+ log_debug("Looking up RR for %s.",
+ dns_resource_key_to_string(key, key_str, sizeof key_str));
+
+ /* And then dump the IDNA question, but only what hasn't been dumped already through the UTF8 question. */
+ DNS_QUESTION_FOREACH(key, question_idna) {
+ r = dns_question_contains(question_utf8, key);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ continue;
+
+ log_debug("Looking up IDNA RR for %s.",
+ dns_resource_key_to_string(key, key_str, sizeof key_str));
+ }
+
+ LIST_PREPEND(queries, m->dns_queries, q);
+ m->n_dns_queries++;
+ q->manager = m;
+
+ if (ret)
+ *ret = q;
+ q = NULL;
+
+ return 0;
+}
+
+int dns_query_make_auxiliary(DnsQuery *q, DnsQuery *auxiliary_for) {
+ assert(q);
+ assert(auxiliary_for);
+
+ /* Ensure that the query is not auxiliary yet, and
+ * nothing else is auxiliary to it either */
+ assert(!q->auxiliary_for);
+ assert(!q->auxiliary_queries);
+
+ /* Ensure that the unit we shall be made auxiliary for isn't
+ * auxiliary itself */
+ assert(!auxiliary_for->auxiliary_for);
+
+ if (auxiliary_for->n_auxiliary_queries >= AUXILIARY_QUERIES_MAX)
+ return -EAGAIN;
+
+ LIST_PREPEND(auxiliary_queries, auxiliary_for->auxiliary_queries, q);
+ q->auxiliary_for = auxiliary_for;
+
+ auxiliary_for->n_auxiliary_queries++;
+ return 0;
+}
+
+static void dns_query_complete(DnsQuery *q, DnsTransactionState state) {
+ assert(q);
+ assert(!DNS_TRANSACTION_IS_LIVE(state));
+ assert(DNS_TRANSACTION_IS_LIVE(q->state));
+
+ /* Note that this call might invalidate the query. Callers
+ * should hence not attempt to access the query or transaction
+ * after calling this function. */
+
+ q->state = state;
+
+ dns_query_stop(q);
+ if (q->complete)
+ q->complete(q);
+}
+
+static int on_query_timeout(sd_event_source *s, usec_t usec, void *userdata) {
+ DnsQuery *q = userdata;
+
+ assert(s);
+ assert(q);
+
+ dns_query_complete(q, DNS_TRANSACTION_TIMEOUT);
+ return 0;
+}
+
+static int dns_query_add_candidate(DnsQuery *q, DnsScope *s) {
+ DnsQueryCandidate *c;
+ int r;
+
+ assert(q);
+ assert(s);
+
+ r = dns_query_candidate_new(&c, q, s);
+ if (r < 0)
+ return r;
+
+ /* If this a single-label domain on DNS, we might append a suitable search domain first. */
+ if ((q->flags & SD_RESOLVED_NO_SEARCH) == 0) {
+ r = dns_scope_name_needs_search_domain(s, dns_question_first_name(q->question_idna));
+ if (r < 0)
+ goto fail;
+ if (r > 0) {
+ /* OK, we need a search domain now. Let's find one for this scope */
+
+ r = dns_query_candidate_next_search_domain(c);
+ if (r <= 0) /* if there's no search domain, then we won't add any transaction. */
+ goto fail;
+ }
+ }
+
+ r = dns_query_candidate_setup_transactions(c);
+ if (r < 0)
+ goto fail;
+
+ return 0;
+
+fail:
+ dns_query_candidate_free(c);
+ return r;
+}
+
+static int dns_query_synthesize_reply(DnsQuery *q, DnsTransactionState *state) {
+ _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
+ int r;
+
+ assert(q);
+ assert(state);
+
+ /* Tries to synthesize localhost RR replies (and others) where appropriate. Note that this is done *after* the
+ * the normal lookup finished. The data from the network hence takes precedence over the data we
+ * synthesize. (But note that many scopes refuse to resolve certain domain names) */
+
+ if (!IN_SET(*state,
+ DNS_TRANSACTION_RCODE_FAILURE,
+ DNS_TRANSACTION_NO_SERVERS,
+ DNS_TRANSACTION_TIMEOUT,
+ DNS_TRANSACTION_ATTEMPTS_MAX_REACHED,
+ DNS_TRANSACTION_NETWORK_DOWN,
+ DNS_TRANSACTION_NOT_FOUND))
+ return 0;
+
+ r = dns_synthesize_answer(
+ q->manager,
+ q->question_utf8,
+ q->ifindex,
+ &answer);
+
+ if (r <= 0)
+ return r;
+
+ dns_query_reset_answer(q);
+
+ q->answer = answer;
+ answer = NULL;
+ q->answer_rcode = DNS_RCODE_SUCCESS;
+ q->answer_protocol = dns_synthesize_protocol(q->flags);
+ q->answer_family = dns_synthesize_family(q->flags);
+ q->answer_authenticated = true;
+
+ *state = DNS_TRANSACTION_SUCCESS;
+
+ return 1;
+}
+
+static int dns_query_try_etc_hosts(DnsQuery *q) {
+ _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
+ int r;
+
+ assert(q);
+
+ /* Looks in /etc/hosts for matching entries. Note that this is done *before* the normal lookup is done. The
+ * data from /etc/hosts hence takes precedence over the network. */
+
+ r = manager_etc_hosts_lookup(
+ q->manager,
+ q->question_utf8,
+ &answer);
+ if (r <= 0)
+ return r;
+
+ dns_query_reset_answer(q);
+
+ q->answer = answer;
+ answer = NULL;
+ q->answer_rcode = DNS_RCODE_SUCCESS;
+ q->answer_protocol = dns_synthesize_protocol(q->flags);
+ q->answer_family = dns_synthesize_family(q->flags);
+ q->answer_authenticated = true;
+
+ return 1;
+}
+
+int dns_query_go(DnsQuery *q) {
+ DnsScopeMatch found = DNS_SCOPE_NO;
+ DnsScope *s, *first = NULL;
+ DnsQueryCandidate *c;
+ int r;
+
+ assert(q);
+
+ if (q->state != DNS_TRANSACTION_NULL)
+ return 0;
+
+ r = dns_query_try_etc_hosts(q);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ dns_query_complete(q, DNS_TRANSACTION_SUCCESS);
+ return 1;
+ }
+
+ LIST_FOREACH(scopes, s, q->manager->dns_scopes) {
+ DnsScopeMatch match;
+ const char *name;
+
+ name = dns_question_first_name(dns_query_question_for_protocol(q, s->protocol));
+ if (!name)
+ continue;
+
+ match = dns_scope_good_domain(s, q->ifindex, q->flags, name);
+ if (match < 0)
+ return match;
+
+ if (match == DNS_SCOPE_NO)
+ continue;
+
+ found = match;
+
+ if (match == DNS_SCOPE_YES) {
+ first = s;
+ break;
+ } else {
+ assert(match == DNS_SCOPE_MAYBE);
+
+ if (!first)
+ first = s;
+ }
+ }
+
+ if (found == DNS_SCOPE_NO) {
+ DnsTransactionState state = DNS_TRANSACTION_NO_SERVERS;
+
+ r = dns_query_synthesize_reply(q, &state);
+ if (r < 0)
+ return r;
+
+ dns_query_complete(q, state);
+ return 1;
+ }
+
+ r = dns_query_add_candidate(q, first);
+ if (r < 0)
+ goto fail;
+
+ LIST_FOREACH(scopes, s, first->scopes_next) {
+ DnsScopeMatch match;
+ const char *name;
+
+ name = dns_question_first_name(dns_query_question_for_protocol(q, s->protocol));
+ if (!name)
+ continue;
+
+ match = dns_scope_good_domain(s, q->ifindex, q->flags, name);
+ if (match < 0)
+ goto fail;
+
+ if (match != found)
+ continue;
+
+ r = dns_query_add_candidate(q, s);
+ if (r < 0)
+ goto fail;
+ }
+
+ dns_query_reset_answer(q);
+
+ r = sd_event_add_time(
+ q->manager->event,
+ &q->timeout_event_source,
+ clock_boottime_or_monotonic(),
+ now(clock_boottime_or_monotonic()) + QUERY_TIMEOUT_USEC, 0,
+ on_query_timeout, q);
+ if (r < 0)
+ goto fail;
+
+ (void) sd_event_source_set_description(q->timeout_event_source, "query-timeout");
+
+ q->state = DNS_TRANSACTION_PENDING;
+ q->block_ready++;
+
+ /* Start the transactions */
+ LIST_FOREACH(candidates_by_query, c, q->candidates) {
+ r = dns_query_candidate_go(c);
+ if (r < 0) {
+ q->block_ready--;
+ goto fail;
+ }
+ }
+
+ q->block_ready--;
+ dns_query_ready(q);
+
+ return 1;
+
+fail:
+ dns_query_stop(q);
+ return r;
+}
+
+static void dns_query_accept(DnsQuery *q, DnsQueryCandidate *c) {
+ DnsTransactionState state = DNS_TRANSACTION_NO_SERVERS;
+ bool has_authenticated = false, has_non_authenticated = false;
+ DnssecResult dnssec_result_authenticated = _DNSSEC_RESULT_INVALID, dnssec_result_non_authenticated = _DNSSEC_RESULT_INVALID;
+ DnsTransaction *t;
+ Iterator i;
+ int r;
+
+ assert(q);
+
+ if (!c) {
+ r = dns_query_synthesize_reply(q, &state);
+ if (r < 0)
+ goto fail;
+
+ dns_query_complete(q, state);
+ return;
+ }
+
+ if (c->error_code != 0) {
+ /* If the candidate had an error condition of its own, start with that. */
+ state = DNS_TRANSACTION_ERRNO;
+ q->answer = dns_answer_unref(q->answer);
+ q->answer_rcode = 0;
+ q->answer_dnssec_result = _DNSSEC_RESULT_INVALID;
+ q->answer_errno = c->error_code;
+ }
+
+ SET_FOREACH(t, c->transactions, i) {
+
+ switch (t->state) {
+
+ case DNS_TRANSACTION_SUCCESS: {
+ /* We found a successfully reply, merge it into the answer */
+ r = dns_answer_extend(&q->answer, t->answer);
+ if (r < 0)
+ goto fail;
+
+ q->answer_rcode = t->answer_rcode;
+ q->answer_errno = 0;
+
+ if (t->answer_authenticated) {
+ has_authenticated = true;
+ dnssec_result_authenticated = t->answer_dnssec_result;
+ } else {
+ has_non_authenticated = true;
+ dnssec_result_non_authenticated = t->answer_dnssec_result;
+ }
+
+ state = DNS_TRANSACTION_SUCCESS;
+ break;
+ }
+
+ case DNS_TRANSACTION_NULL:
+ case DNS_TRANSACTION_PENDING:
+ case DNS_TRANSACTION_VALIDATING:
+ case DNS_TRANSACTION_ABORTED:
+ /* Ignore transactions that didn't complete */
+ continue;
+
+ default:
+ /* Any kind of failure? Store the data away,
+ * if there's nothing stored yet. */
+
+ if (state == DNS_TRANSACTION_SUCCESS)
+ continue;
+
+ q->answer = dns_answer_unref(q->answer);
+ q->answer_rcode = t->answer_rcode;
+ q->answer_dnssec_result = t->answer_dnssec_result;
+ q->answer_errno = t->answer_errno;
+
+ state = t->state;
+ break;
+ }
+ }
+
+ if (state == DNS_TRANSACTION_SUCCESS) {
+ q->answer_authenticated = has_authenticated && !has_non_authenticated;
+ q->answer_dnssec_result = q->answer_authenticated ? dnssec_result_authenticated : dnssec_result_non_authenticated;
+ }
+
+ q->answer_protocol = c->scope->protocol;
+ q->answer_family = c->scope->family;
+
+ dns_search_domain_unref(q->answer_search_domain);
+ q->answer_search_domain = dns_search_domain_ref(c->search_domain);
+
+ r = dns_query_synthesize_reply(q, &state);
+ if (r < 0)
+ goto fail;
+
+ dns_query_complete(q, state);
+ return;
+
+fail:
+ q->answer_errno = -r;
+ dns_query_complete(q, DNS_TRANSACTION_ERRNO);
+}
+
+void dns_query_ready(DnsQuery *q) {
+
+ DnsQueryCandidate *bad = NULL, *c;
+ bool pending = false;
+
+ assert(q);
+ assert(DNS_TRANSACTION_IS_LIVE(q->state));
+
+ /* Note that this call might invalidate the query. Callers
+ * should hence not attempt to access the query or transaction
+ * after calling this function, unless the block_ready
+ * counter was explicitly bumped before doing so. */
+
+ if (q->block_ready > 0)
+ return;
+
+ LIST_FOREACH(candidates_by_query, c, q->candidates) {
+ DnsTransactionState state;
+
+ state = dns_query_candidate_state(c);
+ switch (state) {
+
+ case DNS_TRANSACTION_SUCCESS:
+ /* One of the candidates is successful,
+ * let's use it, and copy its data out */
+ dns_query_accept(q, c);
+ return;
+
+ case DNS_TRANSACTION_NULL:
+ case DNS_TRANSACTION_PENDING:
+ case DNS_TRANSACTION_VALIDATING:
+ /* One of the candidates is still going on,
+ * let's maybe wait for it */
+ pending = true;
+ break;
+
+ default:
+ /* Any kind of failure */
+ bad = c;
+ break;
+ }
+ }
+
+ if (pending)
+ return;
+
+ dns_query_accept(q, bad);
+}
+
+static int dns_query_cname_redirect(DnsQuery *q, const DnsResourceRecord *cname) {
+ _cleanup_(dns_question_unrefp) DnsQuestion *nq_idna = NULL, *nq_utf8 = NULL;
+ int r, k;
+
+ assert(q);
+
+ q->n_cname_redirects++;
+ if (q->n_cname_redirects > CNAME_MAX)
+ return -ELOOP;
+
+ r = dns_question_cname_redirect(q->question_idna, cname, &nq_idna);
+ if (r < 0)
+ return r;
+ else if (r > 0)
+ log_debug("Following CNAME/DNAME %s → %s.", dns_question_first_name(q->question_idna), dns_question_first_name(nq_idna));
+
+ k = dns_question_is_equal(q->question_idna, q->question_utf8);
+ if (k < 0)
+ return r;
+ if (k > 0) {
+ /* Same question? Shortcut new question generation */
+ nq_utf8 = dns_question_ref(nq_idna);
+ k = r;
+ } else {
+ k = dns_question_cname_redirect(q->question_utf8, cname, &nq_utf8);
+ if (k < 0)
+ return k;
+ else if (k > 0)
+ log_debug("Following UTF8 CNAME/DNAME %s → %s.", dns_question_first_name(q->question_utf8), dns_question_first_name(nq_utf8));
+ }
+
+ if (r == 0 && k == 0) /* No actual cname happened? */
+ return -ELOOP;
+
+ if (q->answer_protocol == DNS_PROTOCOL_DNS) {
+ /* Don't permit CNAME redirects from unicast DNS to LLMNR or MulticastDNS, so that global resources
+ * cannot invade the local namespace. The opposite way we permit: local names may redirect to global
+ * ones. */
+
+ q->flags &= ~(SD_RESOLVED_LLMNR|SD_RESOLVED_MDNS); /* mask away the local protocols */
+ }
+
+ /* Turn off searching for the new name */
+ q->flags |= SD_RESOLVED_NO_SEARCH;
+
+ dns_question_unref(q->question_idna);
+ q->question_idna = nq_idna;
+ nq_idna = NULL;
+
+ dns_question_unref(q->question_utf8);
+ q->question_utf8 = nq_utf8;
+ nq_utf8 = NULL;
+
+ dns_query_free_candidates(q);
+ dns_query_reset_answer(q);
+
+ q->state = DNS_TRANSACTION_NULL;
+
+ return 0;
+}
+
+int dns_query_process_cname(DnsQuery *q) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *cname = NULL;
+ DnsQuestion *question;
+ DnsResourceRecord *rr;
+ int r;
+
+ assert(q);
+
+ if (!IN_SET(q->state, DNS_TRANSACTION_SUCCESS, DNS_TRANSACTION_NULL))
+ return DNS_QUERY_NOMATCH;
+
+ question = dns_query_question_for_protocol(q, q->answer_protocol);
+
+ DNS_ANSWER_FOREACH(rr, q->answer) {
+ r = dns_question_matches_rr(question, rr, DNS_SEARCH_DOMAIN_NAME(q->answer_search_domain));
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return DNS_QUERY_MATCH; /* The answer matches directly, no need to follow cnames */
+
+ r = dns_question_matches_cname_or_dname(question, rr, DNS_SEARCH_DOMAIN_NAME(q->answer_search_domain));
+ if (r < 0)
+ return r;
+ if (r > 0 && !cname)
+ cname = dns_resource_record_ref(rr);
+ }
+
+ if (!cname)
+ return DNS_QUERY_NOMATCH; /* No match and no cname to follow */
+
+ if (q->flags & SD_RESOLVED_NO_CNAME)
+ return -ELOOP;
+
+ /* OK, let's actually follow the CNAME */
+ r = dns_query_cname_redirect(q, cname);
+ if (r < 0)
+ return r;
+
+ /* Let's see if the answer can already answer the new
+ * redirected question */
+ r = dns_query_process_cname(q);
+ if (r != DNS_QUERY_NOMATCH)
+ return r;
+
+ /* OK, it cannot, let's begin with the new query */
+ r = dns_query_go(q);
+ if (r < 0)
+ return r;
+
+ return DNS_QUERY_RESTARTED; /* We restarted the query for a new cname */
+}
+
+static int on_bus_track(sd_bus_track *t, void *userdata) {
+ DnsQuery *q = userdata;
+
+ assert(t);
+ assert(q);
+
+ log_debug("Client of active query vanished, aborting query.");
+ dns_query_complete(q, DNS_TRANSACTION_ABORTED);
+ return 0;
+}
+
+int dns_query_bus_track(DnsQuery *q, sd_bus_message *m) {
+ int r;
+
+ assert(q);
+ assert(m);
+
+ if (!q->bus_track) {
+ r = sd_bus_track_new(sd_bus_message_get_bus(m), &q->bus_track, on_bus_track, q);
+ if (r < 0)
+ return r;
+ }
+
+ r = sd_bus_track_add_sender(q->bus_track, m);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+DnsQuestion* dns_query_question_for_protocol(DnsQuery *q, DnsProtocol protocol) {
+ assert(q);
+
+ switch (protocol) {
+
+ case DNS_PROTOCOL_DNS:
+ return q->question_idna;
+
+ case DNS_PROTOCOL_MDNS:
+ case DNS_PROTOCOL_LLMNR:
+ return q->question_utf8;
+
+ default:
+ return NULL;
+ }
+}
+
+const char *dns_query_string(DnsQuery *q) {
+ const char *name;
+ int r;
+
+ /* Returns a somewhat useful human-readable lookup key string for this query */
+
+ if (q->request_address_string)
+ return q->request_address_string;
+
+ if (q->request_address_valid) {
+ r = in_addr_to_string(q->request_family, &q->request_address, &q->request_address_string);
+ if (r >= 0)
+ return q->request_address_string;
+ }
+
+ name = dns_question_first_name(q->question_utf8);
+ if (name)
+ return name;
+
+ return dns_question_first_name(q->question_idna);
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-query.h b/src/grp-resolve/systemd-resolved/resolved-dns-query.h
new file mode 100644
index 0000000000..bc26a58f21
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-query.h
@@ -0,0 +1,141 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+
+#include <systemd/sd-bus.h>
+
+#include "basic-dns/resolved-dns-answer.h"
+#include "basic-dns/resolved-dns-question.h"
+#include "systemd-basic/set.h"
+
+typedef struct DnsQuery DnsQuery;
+typedef struct DnsQueryCandidate DnsQueryCandidate;
+
+#include "resolved-dns-search-domain.h"
+#include "resolved-dns-stream.h"
+
+struct DnsQueryCandidate {
+ DnsQuery *query;
+ DnsScope *scope;
+
+ DnsSearchDomain *search_domain;
+
+ int error_code;
+ Set *transactions;
+
+ LIST_FIELDS(DnsQueryCandidate, candidates_by_query);
+ LIST_FIELDS(DnsQueryCandidate, candidates_by_scope);
+};
+
+struct DnsQuery {
+ Manager *manager;
+
+ /* When resolving a service, we first create a TXT+SRV query,
+ * and then for the hostnames we discover auxiliary A+AAAA
+ * queries. This pointer always points from the auxiliary
+ * queries back to the TXT+SRV query. */
+ DnsQuery *auxiliary_for;
+ LIST_HEAD(DnsQuery, auxiliary_queries);
+ unsigned n_auxiliary_queries;
+ int auxiliary_result;
+
+ /* The question, formatted in IDNA for use on classic DNS, and as UTF8 for use in LLMNR or mDNS. Note that even
+ * on classic DNS some labels might use UTF8 encoding. Specifically, DNS-SD service names (in contrast to their
+ * domain suffixes) use UTF-8 encoding even on DNS. Thus, the difference between these two fields is mostly
+ * relevant only for explicit *hostname* lookups as well as the domain suffixes of service lookups. */
+ DnsQuestion *question_idna;
+ DnsQuestion *question_utf8;
+
+ uint64_t flags;
+ int ifindex;
+
+ /* If true, A or AAAA RR lookups will be suppressed on links with no routable address of the matching address
+ * family */
+ bool suppress_unroutable_family;
+
+
+ /* If true, the RR TTLs of the answer will be clamped by their current left validity in the cache */
+ bool clamp_ttl;
+
+ DnsTransactionState state;
+ unsigned n_cname_redirects;
+
+ LIST_HEAD(DnsQueryCandidate, candidates);
+ sd_event_source *timeout_event_source;
+
+ /* Discovered data */
+ DnsAnswer *answer;
+ int answer_rcode;
+ DnssecResult answer_dnssec_result;
+ bool answer_authenticated;
+ DnsProtocol answer_protocol;
+ int answer_family;
+ DnsSearchDomain *answer_search_domain;
+ int answer_errno; /* if state is DNS_TRANSACTION_ERRNO */
+
+ /* Bus client information */
+ sd_bus_message *request;
+ int request_family;
+ bool request_address_valid;
+ union in_addr_union request_address;
+ unsigned block_all_complete;
+ char *request_address_string;
+
+ /* DNS stub information */
+ DnsPacket *request_dns_packet;
+ DnsStream *request_dns_stream;
+
+ /* Completion callback */
+ void (*complete)(DnsQuery* q);
+ unsigned block_ready;
+
+ sd_bus_track *bus_track;
+
+ LIST_FIELDS(DnsQuery, queries);
+ LIST_FIELDS(DnsQuery, auxiliary_queries);
+};
+
+enum {
+ DNS_QUERY_MATCH,
+ DNS_QUERY_NOMATCH,
+ DNS_QUERY_RESTARTED,
+};
+
+DnsQueryCandidate* dns_query_candidate_free(DnsQueryCandidate *c);
+void dns_query_candidate_notify(DnsQueryCandidate *c);
+
+int dns_query_new(Manager *m, DnsQuery **q, DnsQuestion *question_utf8, DnsQuestion *question_idna, int family, uint64_t flags);
+DnsQuery *dns_query_free(DnsQuery *q);
+
+int dns_query_make_auxiliary(DnsQuery *q, DnsQuery *auxiliary_for);
+
+int dns_query_go(DnsQuery *q);
+void dns_query_ready(DnsQuery *q);
+
+int dns_query_process_cname(DnsQuery *q);
+
+int dns_query_bus_track(DnsQuery *q, sd_bus_message *m);
+
+DnsQuestion* dns_query_question_for_protocol(DnsQuery *q, DnsProtocol protocol);
+
+const char *dns_query_string(DnsQuery *q);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(DnsQuery*, dns_query_free);
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-scope.c b/src/grp-resolve/systemd-resolved/resolved-dns-scope.c
new file mode 100644
index 0000000000..9b7883a410
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-scope.c
@@ -0,0 +1,1038 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <netinet/tcp.h>
+
+#include "systemd-basic/af-list.h"
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/fd-util.h"
+#include "systemd-basic/hostname-util.h"
+#include "systemd-basic/missing.h"
+#include "systemd-basic/random-util.h"
+#include "systemd-basic/socket-util.h"
+#include "systemd-basic/strv.h"
+#include "systemd-shared/dns-domain.h"
+
+#include "resolved-dns-scope.h"
+#include "resolved-llmnr.h"
+#include "resolved-mdns.h"
+
+#define MULTICAST_RATELIMIT_INTERVAL_USEC (1*USEC_PER_SEC)
+#define MULTICAST_RATELIMIT_BURST 1000
+
+/* After how much time to repeat LLMNR requests, see RFC 4795 Section 7 */
+#define MULTICAST_RESEND_TIMEOUT_MIN_USEC (100 * USEC_PER_MSEC)
+#define MULTICAST_RESEND_TIMEOUT_MAX_USEC (1 * USEC_PER_SEC)
+
+int dns_scope_new(Manager *m, DnsScope **ret, Link *l, DnsProtocol protocol, int family) {
+ DnsScope *s;
+
+ assert(m);
+ assert(ret);
+
+ s = new0(DnsScope, 1);
+ if (!s)
+ return -ENOMEM;
+
+ s->manager = m;
+ s->link = l;
+ s->protocol = protocol;
+ s->family = family;
+ s->resend_timeout = MULTICAST_RESEND_TIMEOUT_MIN_USEC;
+
+ if (protocol == DNS_PROTOCOL_DNS) {
+ /* Copy DNSSEC mode from the link if it is set there,
+ * otherwise take the manager's DNSSEC mode. Note that
+ * we copy this only at scope creation time, and do
+ * not update it from the on, even if the setting
+ * changes. */
+
+ if (l)
+ s->dnssec_mode = link_get_dnssec_mode(l);
+ else
+ s->dnssec_mode = manager_get_dnssec_mode(m);
+ } else
+ s->dnssec_mode = DNSSEC_NO;
+
+ LIST_PREPEND(scopes, m->dns_scopes, s);
+
+ dns_scope_llmnr_membership(s, true);
+ dns_scope_mdns_membership(s, true);
+
+ log_debug("New scope on link %s, protocol %s, family %s", l ? l->name : "*", dns_protocol_to_string(protocol), family == AF_UNSPEC ? "*" : af_to_name(family));
+
+ /* Enforce ratelimiting for the multicast protocols */
+ RATELIMIT_INIT(s->ratelimit, MULTICAST_RATELIMIT_INTERVAL_USEC, MULTICAST_RATELIMIT_BURST);
+
+ *ret = s;
+ return 0;
+}
+
+static void dns_scope_abort_transactions(DnsScope *s) {
+ assert(s);
+
+ while (s->transactions) {
+ DnsTransaction *t = s->transactions;
+
+ /* Abort the transaction, but make sure it is not
+ * freed while we still look at it */
+
+ t->block_gc++;
+ if (DNS_TRANSACTION_IS_LIVE(t->state))
+ dns_transaction_complete(t, DNS_TRANSACTION_ABORTED);
+ t->block_gc--;
+
+ dns_transaction_free(t);
+ }
+}
+
+DnsScope* dns_scope_free(DnsScope *s) {
+ DnsResourceRecord *rr;
+
+ if (!s)
+ return NULL;
+
+ log_debug("Removing scope on link %s, protocol %s, family %s", s->link ? s->link->name : "*", dns_protocol_to_string(s->protocol), s->family == AF_UNSPEC ? "*" : af_to_name(s->family));
+
+ dns_scope_llmnr_membership(s, false);
+ dns_scope_mdns_membership(s, false);
+ dns_scope_abort_transactions(s);
+
+ while (s->query_candidates)
+ dns_query_candidate_free(s->query_candidates);
+
+ hashmap_free(s->transactions_by_key);
+
+ while ((rr = ordered_hashmap_steal_first(s->conflict_queue)))
+ dns_resource_record_unref(rr);
+
+ ordered_hashmap_free(s->conflict_queue);
+ sd_event_source_unref(s->conflict_event_source);
+
+ dns_cache_flush(&s->cache);
+ dns_zone_flush(&s->zone);
+
+ LIST_REMOVE(scopes, s->manager->dns_scopes, s);
+ free(s);
+
+ return NULL;
+}
+
+DnsServer *dns_scope_get_dns_server(DnsScope *s) {
+ assert(s);
+
+ if (s->protocol != DNS_PROTOCOL_DNS)
+ return NULL;
+
+ if (s->link)
+ return link_get_dns_server(s->link);
+ else
+ return manager_get_dns_server(s->manager);
+}
+
+void dns_scope_next_dns_server(DnsScope *s) {
+ assert(s);
+
+ if (s->protocol != DNS_PROTOCOL_DNS)
+ return;
+
+ if (s->link)
+ link_next_dns_server(s->link);
+ else
+ manager_next_dns_server(s->manager);
+}
+
+void dns_scope_packet_received(DnsScope *s, usec_t rtt) {
+ assert(s);
+
+ if (rtt <= s->max_rtt)
+ return;
+
+ s->max_rtt = rtt;
+ s->resend_timeout = MIN(MAX(MULTICAST_RESEND_TIMEOUT_MIN_USEC, s->max_rtt * 2), MULTICAST_RESEND_TIMEOUT_MAX_USEC);
+}
+
+void dns_scope_packet_lost(DnsScope *s, usec_t usec) {
+ assert(s);
+
+ if (s->resend_timeout <= usec)
+ s->resend_timeout = MIN(s->resend_timeout * 2, MULTICAST_RESEND_TIMEOUT_MAX_USEC);
+}
+
+static int dns_scope_emit_one(DnsScope *s, int fd, DnsPacket *p) {
+ union in_addr_union addr;
+ int ifindex = 0, r;
+ int family;
+ uint32_t mtu;
+
+ assert(s);
+ assert(p);
+ assert(p->protocol == s->protocol);
+
+ if (s->link) {
+ mtu = s->link->mtu;
+ ifindex = s->link->ifindex;
+ } else
+ mtu = manager_find_mtu(s->manager);
+
+ switch (s->protocol) {
+
+ case DNS_PROTOCOL_DNS:
+ assert(fd >= 0);
+
+ if (DNS_PACKET_QDCOUNT(p) > 1)
+ return -EOPNOTSUPP;
+
+ if (p->size > DNS_PACKET_UNICAST_SIZE_MAX)
+ return -EMSGSIZE;
+
+ if (p->size + UDP_PACKET_HEADER_SIZE > mtu)
+ return -EMSGSIZE;
+
+ r = manager_write(s->manager, fd, p);
+ if (r < 0)
+ return r;
+
+ break;
+
+ case DNS_PROTOCOL_LLMNR:
+ assert(fd < 0);
+
+ if (DNS_PACKET_QDCOUNT(p) > 1)
+ return -EOPNOTSUPP;
+
+ if (!ratelimit_test(&s->ratelimit))
+ return -EBUSY;
+
+ family = s->family;
+
+ if (family == AF_INET) {
+ addr.in = LLMNR_MULTICAST_IPV4_ADDRESS;
+ fd = manager_llmnr_ipv4_udp_fd(s->manager);
+ } else if (family == AF_INET6) {
+ addr.in6 = LLMNR_MULTICAST_IPV6_ADDRESS;
+ fd = manager_llmnr_ipv6_udp_fd(s->manager);
+ } else
+ return -EAFNOSUPPORT;
+ if (fd < 0)
+ return fd;
+
+ r = manager_send(s->manager, fd, ifindex, family, &addr, LLMNR_PORT, NULL, p);
+ if (r < 0)
+ return r;
+
+ break;
+
+ case DNS_PROTOCOL_MDNS:
+ assert(fd < 0);
+
+ if (!ratelimit_test(&s->ratelimit))
+ return -EBUSY;
+
+ family = s->family;
+
+ if (family == AF_INET) {
+ addr.in = MDNS_MULTICAST_IPV4_ADDRESS;
+ fd = manager_mdns_ipv4_fd(s->manager);
+ } else if (family == AF_INET6) {
+ addr.in6 = MDNS_MULTICAST_IPV6_ADDRESS;
+ fd = manager_mdns_ipv6_fd(s->manager);
+ } else
+ return -EAFNOSUPPORT;
+ if (fd < 0)
+ return fd;
+
+ r = manager_send(s->manager, fd, ifindex, family, &addr, MDNS_PORT, NULL, p);
+ if (r < 0)
+ return r;
+
+ break;
+
+ default:
+ return -EAFNOSUPPORT;
+ }
+
+ return 1;
+}
+
+int dns_scope_emit_udp(DnsScope *s, int fd, DnsPacket *p) {
+ int r;
+
+ assert(s);
+ assert(p);
+ assert(p->protocol == s->protocol);
+ assert((s->protocol == DNS_PROTOCOL_DNS) == (fd >= 0));
+
+ do {
+ /* If there are multiple linked packets, set the TC bit in all but the last of them */
+ if (p->more) {
+ assert(p->protocol == DNS_PROTOCOL_MDNS);
+ dns_packet_set_flags(p, true, true);
+ }
+
+ r = dns_scope_emit_one(s, fd, p);
+ if (r < 0)
+ return r;
+
+ p = p->more;
+ } while (p);
+
+ return 0;
+}
+
+static int dns_scope_socket(
+ DnsScope *s,
+ int type,
+ int family,
+ const union in_addr_union *address,
+ DnsServer *server,
+ uint16_t port) {
+
+ _cleanup_close_ int fd = -1;
+ union sockaddr_union sa = {};
+ socklen_t salen;
+ static const int one = 1;
+ int ret, r, ifindex;
+
+ assert(s);
+
+ if (server) {
+ assert(family == AF_UNSPEC);
+ assert(!address);
+
+ ifindex = dns_server_ifindex(server);
+
+ sa.sa.sa_family = server->family;
+ if (server->family == AF_INET) {
+ sa.in.sin_port = htobe16(port);
+ sa.in.sin_addr = server->address.in;
+ salen = sizeof(sa.in);
+ } else if (server->family == AF_INET6) {
+ sa.in6.sin6_port = htobe16(port);
+ sa.in6.sin6_addr = server->address.in6;
+ sa.in6.sin6_scope_id = ifindex;
+ salen = sizeof(sa.in6);
+ } else
+ return -EAFNOSUPPORT;
+ } else {
+ assert(family != AF_UNSPEC);
+ assert(address);
+
+ sa.sa.sa_family = family;
+ ifindex = s->link ? s->link->ifindex : 0;
+
+ if (family == AF_INET) {
+ sa.in.sin_port = htobe16(port);
+ sa.in.sin_addr = address->in;
+ salen = sizeof(sa.in);
+ } else if (family == AF_INET6) {
+ sa.in6.sin6_port = htobe16(port);
+ sa.in6.sin6_addr = address->in6;
+ sa.in6.sin6_scope_id = ifindex;
+ salen = sizeof(sa.in6);
+ } else
+ return -EAFNOSUPPORT;
+ }
+
+ fd = socket(sa.sa.sa_family, type|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (fd < 0)
+ return -errno;
+
+ if (type == SOCK_STREAM) {
+ r = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &one, sizeof(one));
+ if (r < 0)
+ return -errno;
+ }
+
+ if (s->link) {
+ be32_t ifindex_be = htobe32(ifindex);
+
+ if (sa.sa.sa_family == AF_INET) {
+ r = setsockopt(fd, IPPROTO_IP, IP_UNICAST_IF, &ifindex_be, sizeof(ifindex_be));
+ if (r < 0)
+ return -errno;
+ } else if (sa.sa.sa_family == AF_INET6) {
+ r = setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_IF, &ifindex_be, sizeof(ifindex_be));
+ if (r < 0)
+ return -errno;
+ }
+ }
+
+ if (s->protocol == DNS_PROTOCOL_LLMNR) {
+ /* RFC 4795, section 2.5 requires the TTL to be set to 1 */
+
+ if (sa.sa.sa_family == AF_INET) {
+ r = setsockopt(fd, IPPROTO_IP, IP_TTL, &one, sizeof(one));
+ if (r < 0)
+ return -errno;
+ } else if (sa.sa.sa_family == AF_INET6) {
+ r = setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &one, sizeof(one));
+ if (r < 0)
+ return -errno;
+ }
+ }
+
+ r = connect(fd, &sa.sa, salen);
+ if (r < 0 && errno != EINPROGRESS)
+ return -errno;
+
+ ret = fd;
+ fd = -1;
+
+ return ret;
+}
+
+int dns_scope_socket_udp(DnsScope *s, DnsServer *server, uint16_t port) {
+ return dns_scope_socket(s, SOCK_DGRAM, AF_UNSPEC, NULL, server, port);
+}
+
+int dns_scope_socket_tcp(DnsScope *s, int family, const union in_addr_union *address, DnsServer *server, uint16_t port) {
+ return dns_scope_socket(s, SOCK_STREAM, family, address, server, port);
+}
+
+DnsScopeMatch dns_scope_good_domain(DnsScope *s, int ifindex, uint64_t flags, const char *domain) {
+ DnsSearchDomain *d;
+
+ assert(s);
+ assert(domain);
+
+ /* Checks if the specified domain is something to look up on
+ * this scope. Note that this accepts non-qualified hostnames,
+ * i.e. those without any search path prefixed yet. */
+
+ if (ifindex != 0 && (!s->link || s->link->ifindex != ifindex))
+ return DNS_SCOPE_NO;
+
+ if ((SD_RESOLVED_FLAGS_MAKE(s->protocol, s->family, 0) & flags) == 0)
+ return DNS_SCOPE_NO;
+
+ /* Never resolve any loopback hostname or IP address via DNS,
+ * LLMNR or mDNS. Instead, always rely on synthesized RRs for
+ * these. */
+ if (is_localhost(domain) ||
+ dns_name_endswith(domain, "127.in-addr.arpa") > 0 ||
+ dns_name_equal(domain, "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa") > 0)
+ return DNS_SCOPE_NO;
+
+ /* Never respond to some of the domains listed in RFC6303 */
+ if (dns_name_endswith(domain, "0.in-addr.arpa") > 0 ||
+ dns_name_equal(domain, "255.255.255.255.in-addr.arpa") > 0 ||
+ dns_name_equal(domain, "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa") > 0)
+ return DNS_SCOPE_NO;
+
+ /* Never respond to some of the domains listed in RFC6761 */
+ if (dns_name_endswith(domain, "invalid") > 0)
+ return DNS_SCOPE_NO;
+
+ /* Always honour search domains for routing queries. Note that
+ * we return DNS_SCOPE_YES here, rather than just
+ * DNS_SCOPE_MAYBE, which means wildcard scopes won't be
+ * considered anymore. */
+ LIST_FOREACH(domains, d, dns_scope_get_search_domains(s))
+ if (dns_name_endswith(domain, d->name) > 0)
+ return DNS_SCOPE_YES;
+
+ switch (s->protocol) {
+
+ case DNS_PROTOCOL_DNS:
+
+ /* Exclude link-local IP ranges */
+ if (dns_name_endswith(domain, "254.169.in-addr.arpa") == 0 &&
+ dns_name_endswith(domain, "8.e.f.ip6.arpa") == 0 &&
+ dns_name_endswith(domain, "9.e.f.ip6.arpa") == 0 &&
+ dns_name_endswith(domain, "a.e.f.ip6.arpa") == 0 &&
+ dns_name_endswith(domain, "b.e.f.ip6.arpa") == 0 &&
+ /* If networks use .local in their private setups, they are supposed to also add .local to their search
+ * domains, which we already checked above. Otherwise, we consider .local specific to mDNS and won't
+ * send such queries ordinary DNS servers. */
+ dns_name_endswith(domain, "local") == 0)
+ return DNS_SCOPE_MAYBE;
+
+ return DNS_SCOPE_NO;
+
+ case DNS_PROTOCOL_MDNS:
+ if ((s->family == AF_INET && dns_name_endswith(domain, "in-addr.arpa") > 0) ||
+ (s->family == AF_INET6 && dns_name_endswith(domain, "ip6.arpa") > 0) ||
+ (dns_name_endswith(domain, "local") > 0 && /* only resolve names ending in .local via mDNS */
+ dns_name_equal(domain, "local") == 0 && /* but not the single-label "local" name itself */
+ manager_is_own_hostname(s->manager, domain) <= 0)) /* never resolve the local hostname via mDNS */
+ return DNS_SCOPE_MAYBE;
+
+ return DNS_SCOPE_NO;
+
+ case DNS_PROTOCOL_LLMNR:
+ if ((s->family == AF_INET && dns_name_endswith(domain, "in-addr.arpa") > 0) ||
+ (s->family == AF_INET6 && dns_name_endswith(domain, "ip6.arpa") > 0) ||
+ (dns_name_is_single_label(domain) && /* only resolve single label names via LLMNR */
+ !is_gateway_hostname(domain) && /* don't resolve "gateway" with LLMNR, let nss-myhostname handle this */
+ manager_is_own_hostname(s->manager, domain) <= 0)) /* never resolve the local hostname via LLMNR */
+ return DNS_SCOPE_MAYBE;
+
+ return DNS_SCOPE_NO;
+
+ default:
+ assert_not_reached("Unknown scope protocol");
+ }
+}
+
+bool dns_scope_good_key(DnsScope *s, const DnsResourceKey *key) {
+ int key_family;
+
+ assert(s);
+ assert(key);
+
+ /* Check if it makes sense to resolve the specified key on
+ * this scope. Note that this call assumes as fully qualified
+ * name, i.e. the search suffixes already appended. */
+
+ if (key->class != DNS_CLASS_IN)
+ return false;
+
+ if (s->protocol == DNS_PROTOCOL_DNS) {
+
+ /* On classic DNS, looking up non-address RRs is always
+ * fine. (Specifically, we want to permit looking up
+ * DNSKEY and DS records on the root and top-level
+ * domains.) */
+ if (!dns_resource_key_is_address(key))
+ return true;
+
+ /* However, we refuse to look up A and AAAA RRs on the
+ * root and single-label domains, under the assumption
+ * that those should be resolved via LLMNR or search
+ * path only, and should not be leaked onto the
+ * internet. */
+ return !(dns_name_is_single_label(dns_resource_key_name(key)) ||
+ dns_name_is_root(dns_resource_key_name(key)));
+ }
+
+ /* On mDNS and LLMNR, send A and AAAA queries only on the
+ * respective scopes */
+
+ key_family = dns_type_to_af(key->type);
+ if (key_family < 0)
+ return true;
+
+ return key_family == s->family;
+}
+
+static int dns_scope_multicast_membership(DnsScope *s, bool b, struct in_addr in, struct in6_addr in6) {
+ int fd;
+
+ assert(s);
+ assert(s->link);
+
+ if (s->family == AF_INET) {
+ struct ip_mreqn mreqn = {
+ .imr_multiaddr = in,
+ .imr_ifindex = s->link->ifindex,
+ };
+
+ fd = manager_llmnr_ipv4_udp_fd(s->manager);
+ if (fd < 0)
+ return fd;
+
+ /* Always first try to drop membership before we add
+ * one. This is necessary on some devices, such as
+ * veth. */
+ if (b)
+ (void) setsockopt(fd, IPPROTO_IP, IP_DROP_MEMBERSHIP, &mreqn, sizeof(mreqn));
+
+ if (setsockopt(fd, IPPROTO_IP, b ? IP_ADD_MEMBERSHIP : IP_DROP_MEMBERSHIP, &mreqn, sizeof(mreqn)) < 0)
+ return -errno;
+
+ } else if (s->family == AF_INET6) {
+ struct ipv6_mreq mreq = {
+ .ipv6mr_multiaddr = in6,
+ .ipv6mr_interface = s->link->ifindex,
+ };
+
+ fd = manager_llmnr_ipv6_udp_fd(s->manager);
+ if (fd < 0)
+ return fd;
+
+ if (b)
+ (void) setsockopt(fd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq, sizeof(mreq));
+
+ if (setsockopt(fd, IPPROTO_IPV6, b ? IPV6_ADD_MEMBERSHIP : IPV6_DROP_MEMBERSHIP, &mreq, sizeof(mreq)) < 0)
+ return -errno;
+ } else
+ return -EAFNOSUPPORT;
+
+ return 0;
+}
+
+int dns_scope_llmnr_membership(DnsScope *s, bool b) {
+ assert(s);
+
+ if (s->protocol != DNS_PROTOCOL_LLMNR)
+ return 0;
+
+ return dns_scope_multicast_membership(s, b, LLMNR_MULTICAST_IPV4_ADDRESS, LLMNR_MULTICAST_IPV6_ADDRESS);
+}
+
+int dns_scope_mdns_membership(DnsScope *s, bool b) {
+ assert(s);
+
+ if (s->protocol != DNS_PROTOCOL_MDNS)
+ return 0;
+
+ return dns_scope_multicast_membership(s, b, MDNS_MULTICAST_IPV4_ADDRESS, MDNS_MULTICAST_IPV6_ADDRESS);
+}
+
+static int dns_scope_make_reply_packet(
+ DnsScope *s,
+ uint16_t id,
+ int rcode,
+ DnsQuestion *q,
+ DnsAnswer *answer,
+ DnsAnswer *soa,
+ bool tentative,
+ DnsPacket **ret) {
+
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ int r;
+
+ assert(s);
+ assert(ret);
+
+ if (dns_question_isempty(q) &&
+ dns_answer_isempty(answer) &&
+ dns_answer_isempty(soa))
+ return -EINVAL;
+
+ r = dns_packet_new(&p, s->protocol, 0);
+ if (r < 0)
+ return r;
+
+ DNS_PACKET_HEADER(p)->id = id;
+ DNS_PACKET_HEADER(p)->flags = htobe16(DNS_PACKET_MAKE_FLAGS(
+ 1 /* qr */,
+ 0 /* opcode */,
+ 0 /* c */,
+ 0 /* tc */,
+ tentative,
+ 0 /* (ra) */,
+ 0 /* (ad) */,
+ 0 /* (cd) */,
+ rcode));
+
+ r = dns_packet_append_question(p, q);
+ if (r < 0)
+ return r;
+ DNS_PACKET_HEADER(p)->qdcount = htobe16(dns_question_size(q));
+
+ r = dns_packet_append_answer(p, answer);
+ if (r < 0)
+ return r;
+ DNS_PACKET_HEADER(p)->ancount = htobe16(dns_answer_size(answer));
+
+ r = dns_packet_append_answer(p, soa);
+ if (r < 0)
+ return r;
+ DNS_PACKET_HEADER(p)->arcount = htobe16(dns_answer_size(soa));
+
+ *ret = p;
+ p = NULL;
+
+ return 0;
+}
+
+static void dns_scope_verify_conflicts(DnsScope *s, DnsPacket *p) {
+ DnsResourceRecord *rr;
+ DnsResourceKey *key;
+
+ assert(s);
+ assert(p);
+
+ DNS_QUESTION_FOREACH(key, p->question)
+ dns_zone_verify_conflicts(&s->zone, key);
+
+ DNS_ANSWER_FOREACH(rr, p->answer)
+ dns_zone_verify_conflicts(&s->zone, rr->key);
+}
+
+void dns_scope_process_query(DnsScope *s, DnsStream *stream, DnsPacket *p) {
+ _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL, *soa = NULL;
+ _cleanup_(dns_packet_unrefp) DnsPacket *reply = NULL;
+ DnsResourceKey *key = NULL;
+ bool tentative = false;
+ int r;
+
+ assert(s);
+ assert(p);
+
+ if (p->protocol != DNS_PROTOCOL_LLMNR)
+ return;
+
+ if (p->ipproto == IPPROTO_UDP) {
+ /* Don't accept UDP queries directed to anything but
+ * the LLMNR multicast addresses. See RFC 4795,
+ * section 2.5. */
+
+ if (p->family == AF_INET && !in_addr_equal(AF_INET, &p->destination, (union in_addr_union*) &LLMNR_MULTICAST_IPV4_ADDRESS))
+ return;
+
+ if (p->family == AF_INET6 && !in_addr_equal(AF_INET6, &p->destination, (union in_addr_union*) &LLMNR_MULTICAST_IPV6_ADDRESS))
+ return;
+ }
+
+ r = dns_packet_extract(p);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to extract resource records from incoming packet: %m");
+ return;
+ }
+
+ if (DNS_PACKET_LLMNR_C(p)) {
+ /* Somebody notified us about a possible conflict */
+ dns_scope_verify_conflicts(s, p);
+ return;
+ }
+
+ assert(dns_question_size(p->question) == 1);
+ key = p->question->keys[0];
+
+ r = dns_zone_lookup(&s->zone, key, 0, &answer, &soa, &tentative);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to lookup key: %m");
+ return;
+ }
+ if (r == 0)
+ return;
+
+ if (answer)
+ dns_answer_order_by_scope(answer, in_addr_is_link_local(p->family, &p->sender) > 0);
+
+ r = dns_scope_make_reply_packet(s, DNS_PACKET_ID(p), DNS_RCODE_SUCCESS, p->question, answer, soa, tentative, &reply);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to build reply packet: %m");
+ return;
+ }
+
+ if (stream) {
+ r = dns_stream_write_packet(stream, reply);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to enqueue reply packet: %m");
+ return;
+ }
+
+ /* Let's take an extra reference on this stream, so that it stays around after returning. The reference
+ * will be dangling until the stream is disconnected, and the default completion handler of the stream
+ * will then unref the stream and destroy it */
+ if (DNS_STREAM_QUEUED(stream))
+ dns_stream_ref(stream);
+ } else {
+ int fd;
+
+ if (!ratelimit_test(&s->ratelimit))
+ return;
+
+ if (p->family == AF_INET)
+ fd = manager_llmnr_ipv4_udp_fd(s->manager);
+ else if (p->family == AF_INET6)
+ fd = manager_llmnr_ipv6_udp_fd(s->manager);
+ else {
+ log_debug("Unknown protocol");
+ return;
+ }
+ if (fd < 0) {
+ log_debug_errno(fd, "Failed to get reply socket: %m");
+ return;
+ }
+
+ /* Note that we always immediately reply to all LLMNR
+ * requests, and do not wait any time, since we
+ * verified uniqueness for all records. Also see RFC
+ * 4795, Section 2.7 */
+
+ r = manager_send(s->manager, fd, p->ifindex, p->family, &p->sender, p->sender_port, NULL, reply);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to send reply packet: %m");
+ return;
+ }
+ }
+}
+
+DnsTransaction *dns_scope_find_transaction(DnsScope *scope, DnsResourceKey *key, bool cache_ok) {
+ DnsTransaction *t;
+
+ assert(scope);
+ assert(key);
+
+ /* Try to find an ongoing transaction that is a equal to the
+ * specified question */
+ t = hashmap_get(scope->transactions_by_key, key);
+ if (!t)
+ return NULL;
+
+ /* Refuse reusing transactions that completed based on cached
+ * data instead of a real packet, if that's requested. */
+ if (!cache_ok &&
+ IN_SET(t->state, DNS_TRANSACTION_SUCCESS, DNS_TRANSACTION_RCODE_FAILURE) &&
+ t->answer_source != DNS_TRANSACTION_NETWORK)
+ return NULL;
+
+ return t;
+}
+
+static int dns_scope_make_conflict_packet(
+ DnsScope *s,
+ DnsResourceRecord *rr,
+ DnsPacket **ret) {
+
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ int r;
+
+ assert(s);
+ assert(rr);
+ assert(ret);
+
+ r = dns_packet_new(&p, s->protocol, 0);
+ if (r < 0)
+ return r;
+
+ DNS_PACKET_HEADER(p)->flags = htobe16(DNS_PACKET_MAKE_FLAGS(
+ 0 /* qr */,
+ 0 /* opcode */,
+ 1 /* conflict */,
+ 0 /* tc */,
+ 0 /* t */,
+ 0 /* (ra) */,
+ 0 /* (ad) */,
+ 0 /* (cd) */,
+ 0));
+
+ /* For mDNS, the transaction ID should always be 0 */
+ if (s->protocol != DNS_PROTOCOL_MDNS)
+ random_bytes(&DNS_PACKET_HEADER(p)->id, sizeof(uint16_t));
+
+ DNS_PACKET_HEADER(p)->qdcount = htobe16(1);
+ DNS_PACKET_HEADER(p)->arcount = htobe16(1);
+
+ r = dns_packet_append_key(p, rr->key, NULL);
+ if (r < 0)
+ return r;
+
+ r = dns_packet_append_rr(p, rr, NULL, NULL);
+ if (r < 0)
+ return r;
+
+ *ret = p;
+ p = NULL;
+
+ return 0;
+}
+
+static int on_conflict_dispatch(sd_event_source *es, usec_t usec, void *userdata) {
+ DnsScope *scope = userdata;
+ int r;
+
+ assert(es);
+ assert(scope);
+
+ scope->conflict_event_source = sd_event_source_unref(scope->conflict_event_source);
+
+ for (;;) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+
+ rr = ordered_hashmap_steal_first(scope->conflict_queue);
+ if (!rr)
+ break;
+
+ r = dns_scope_make_conflict_packet(scope, rr, &p);
+ if (r < 0) {
+ log_error_errno(r, "Failed to make conflict packet: %m");
+ return 0;
+ }
+
+ r = dns_scope_emit_udp(scope, -1, p);
+ if (r < 0)
+ log_debug_errno(r, "Failed to send conflict packet: %m");
+ }
+
+ return 0;
+}
+
+int dns_scope_notify_conflict(DnsScope *scope, DnsResourceRecord *rr) {
+ usec_t jitter;
+ int r;
+
+ assert(scope);
+ assert(rr);
+
+ /* We don't send these queries immediately. Instead, we queue
+ * them, and send them after some jitter delay. */
+ r = ordered_hashmap_ensure_allocated(&scope->conflict_queue, &dns_resource_key_hash_ops);
+ if (r < 0) {
+ log_oom();
+ return r;
+ }
+
+ /* We only place one RR per key in the conflict
+ * messages, not all of them. That should be enough to
+ * indicate where there might be a conflict */
+ r = ordered_hashmap_put(scope->conflict_queue, rr->key, rr);
+ if (r == -EEXIST || r == 0)
+ return 0;
+ if (r < 0)
+ return log_debug_errno(r, "Failed to queue conflicting RR: %m");
+
+ dns_resource_record_ref(rr);
+
+ if (scope->conflict_event_source)
+ return 0;
+
+ random_bytes(&jitter, sizeof(jitter));
+ jitter %= LLMNR_JITTER_INTERVAL_USEC;
+
+ r = sd_event_add_time(scope->manager->event,
+ &scope->conflict_event_source,
+ clock_boottime_or_monotonic(),
+ now(clock_boottime_or_monotonic()) + jitter,
+ LLMNR_JITTER_INTERVAL_USEC,
+ on_conflict_dispatch, scope);
+ if (r < 0)
+ return log_debug_errno(r, "Failed to add conflict dispatch event: %m");
+
+ (void) sd_event_source_set_description(scope->conflict_event_source, "scope-conflict");
+
+ return 0;
+}
+
+void dns_scope_check_conflicts(DnsScope *scope, DnsPacket *p) {
+ unsigned i;
+ int r;
+
+ assert(scope);
+ assert(p);
+
+ if (p->protocol != DNS_PROTOCOL_LLMNR)
+ return;
+
+ if (DNS_PACKET_RRCOUNT(p) <= 0)
+ return;
+
+ if (DNS_PACKET_LLMNR_C(p) != 0)
+ return;
+
+ if (DNS_PACKET_LLMNR_T(p) != 0)
+ return;
+
+ if (manager_our_packet(scope->manager, p))
+ return;
+
+ r = dns_packet_extract(p);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to extract packet: %m");
+ return;
+ }
+
+ log_debug("Checking for conflicts...");
+
+ for (i = 0; i < p->answer->n_rrs; i++) {
+
+ /* Check for conflicts against the local zone. If we
+ * found one, we won't check any further */
+ r = dns_zone_check_conflicts(&scope->zone, p->answer->items[i].rr);
+ if (r != 0)
+ continue;
+
+ /* Check for conflicts against the local cache. If so,
+ * send out an advisory query, to inform everybody */
+ r = dns_cache_check_conflicts(&scope->cache, p->answer->items[i].rr, p->family, &p->sender);
+ if (r <= 0)
+ continue;
+
+ dns_scope_notify_conflict(scope, p->answer->items[i].rr);
+ }
+}
+
+void dns_scope_dump(DnsScope *s, FILE *f) {
+ assert(s);
+
+ if (!f)
+ f = stdout;
+
+ fputs("[Scope protocol=", f);
+ fputs(dns_protocol_to_string(s->protocol), f);
+
+ if (s->link) {
+ fputs(" interface=", f);
+ fputs(s->link->name, f);
+ }
+
+ if (s->family != AF_UNSPEC) {
+ fputs(" family=", f);
+ fputs(af_to_name(s->family), f);
+ }
+
+ fputs("]\n", f);
+
+ if (!dns_zone_is_empty(&s->zone)) {
+ fputs("ZONE:\n", f);
+ dns_zone_dump(&s->zone, f);
+ }
+
+ if (!dns_cache_is_empty(&s->cache)) {
+ fputs("CACHE:\n", f);
+ dns_cache_dump(&s->cache, f);
+ }
+}
+
+DnsSearchDomain *dns_scope_get_search_domains(DnsScope *s) {
+ assert(s);
+
+ if (s->protocol != DNS_PROTOCOL_DNS)
+ return NULL;
+
+ if (s->link)
+ return s->link->search_domains;
+
+ return s->manager->search_domains;
+}
+
+bool dns_scope_name_needs_search_domain(DnsScope *s, const char *name) {
+ assert(s);
+
+ if (s->protocol != DNS_PROTOCOL_DNS)
+ return false;
+
+ return dns_name_is_single_label(name);
+}
+
+bool dns_scope_network_good(DnsScope *s) {
+ /* Checks whether the network is in good state for lookups on this scope. For mDNS/LLMNR/Classic DNS scopes
+ * bound to links this is easy, as they don't even exist if the link isn't in a suitable state. For the global
+ * DNS scope we check whether there are any links that are up and have an address. */
+
+ if (s->link)
+ return true;
+
+ return manager_routable(s->manager, AF_UNSPEC);
+}
+
+int dns_scope_ifindex(DnsScope *s) {
+ assert(s);
+
+ if (s->link)
+ return s->link->ifindex;
+
+ return 0;
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-scope.h b/src/grp-resolve/systemd-resolved/resolved-dns-scope.h
new file mode 100644
index 0000000000..8f35fd841a
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-scope.h
@@ -0,0 +1,111 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "basic-dns/resolved-dns-dnssec.h"
+#include "basic-dns/resolved-dns-packet.h"
+#include "systemd-basic/list.h"
+
+typedef struct DnsScope DnsScope;
+
+#include "resolved-dns-cache.h"
+#include "resolved-dns-server.h"
+#include "resolved-dns-zone.h"
+#include "resolved-link.h"
+
+typedef enum DnsScopeMatch {
+ DNS_SCOPE_NO,
+ DNS_SCOPE_MAYBE,
+ DNS_SCOPE_YES,
+ _DNS_SCOPE_MATCH_MAX,
+ _DNS_SCOPE_INVALID = -1
+} DnsScopeMatch;
+
+struct DnsScope {
+ Manager *manager;
+
+ DnsProtocol protocol;
+ int family;
+ DnssecMode dnssec_mode;
+
+ Link *link;
+
+ DnsCache cache;
+ DnsZone zone;
+
+ OrderedHashmap *conflict_queue;
+ sd_event_source *conflict_event_source;
+
+ RateLimit ratelimit;
+
+ usec_t resend_timeout;
+ usec_t max_rtt;
+
+ LIST_HEAD(DnsQueryCandidate, query_candidates);
+
+ /* Note that we keep track of ongoing transactions in two
+ * ways: once in a hashmap, indexed by the rr key, and once in
+ * a linked list. We use the hashmap to quickly find
+ * transactions we can reuse for a key. But note that there
+ * might be multiple transactions for the same key (because
+ * the zone probing can't reuse a transaction answered from
+ * the zone or the cache), and the hashmap only tracks the
+ * most recent entry. */
+ Hashmap *transactions_by_key;
+ LIST_HEAD(DnsTransaction, transactions);
+
+ LIST_FIELDS(DnsScope, scopes);
+};
+
+int dns_scope_new(Manager *m, DnsScope **ret, Link *l, DnsProtocol p, int family);
+DnsScope* dns_scope_free(DnsScope *s);
+
+void dns_scope_packet_received(DnsScope *s, usec_t rtt);
+void dns_scope_packet_lost(DnsScope *s, usec_t usec);
+
+int dns_scope_emit_udp(DnsScope *s, int fd, DnsPacket *p);
+int dns_scope_socket_tcp(DnsScope *s, int family, const union in_addr_union *address, DnsServer *server, uint16_t port);
+int dns_scope_socket_udp(DnsScope *s, DnsServer *server, uint16_t port);
+
+DnsScopeMatch dns_scope_good_domain(DnsScope *s, int ifindex, uint64_t flags, const char *domain);
+bool dns_scope_good_key(DnsScope *s, const DnsResourceKey *key);
+
+DnsServer *dns_scope_get_dns_server(DnsScope *s);
+void dns_scope_next_dns_server(DnsScope *s);
+
+int dns_scope_llmnr_membership(DnsScope *s, bool b);
+int dns_scope_mdns_membership(DnsScope *s, bool b);
+
+void dns_scope_process_query(DnsScope *s, DnsStream *stream, DnsPacket *p);
+
+DnsTransaction *dns_scope_find_transaction(DnsScope *scope, DnsResourceKey *key, bool cache_ok);
+
+int dns_scope_notify_conflict(DnsScope *scope, DnsResourceRecord *rr);
+void dns_scope_check_conflicts(DnsScope *scope, DnsPacket *p);
+
+void dns_scope_dump(DnsScope *s, FILE *f);
+
+DnsSearchDomain *dns_scope_get_search_domains(DnsScope *s);
+
+bool dns_scope_name_needs_search_domain(DnsScope *s, const char *name);
+
+bool dns_scope_network_good(DnsScope *s);
+
+int dns_scope_ifindex(DnsScope *s);
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-search-domain.c b/src/grp-resolve/systemd-resolved/resolved-dns-search-domain.c
new file mode 100644
index 0000000000..5ddbc7504e
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-search-domain.c
@@ -0,0 +1,228 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2015 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "systemd-basic/alloc-util.h"
+#include "systemd-shared/dns-domain.h"
+
+#include "resolved-dns-search-domain.h"
+
+int dns_search_domain_new(
+ Manager *m,
+ DnsSearchDomain **ret,
+ DnsSearchDomainType type,
+ Link *l,
+ const char *name) {
+
+ _cleanup_free_ char *normalized = NULL;
+ DnsSearchDomain *d;
+ int r;
+
+ assert(m);
+ assert((type == DNS_SEARCH_DOMAIN_LINK) == !!l);
+ assert(name);
+
+ r = dns_name_normalize(name, &normalized);
+ if (r < 0)
+ return r;
+
+ if (l) {
+ if (l->n_search_domains >= LINK_SEARCH_DOMAINS_MAX)
+ return -E2BIG;
+ } else {
+ if (m->n_search_domains >= MANAGER_SEARCH_DOMAINS_MAX)
+ return -E2BIG;
+ }
+
+ d = new0(DnsSearchDomain, 1);
+ if (!d)
+ return -ENOMEM;
+
+ d->n_ref = 1;
+ d->manager = m;
+ d->type = type;
+ d->name = normalized;
+ normalized = NULL;
+
+ switch (type) {
+
+ case DNS_SEARCH_DOMAIN_LINK:
+ d->link = l;
+ LIST_APPEND(domains, l->search_domains, d);
+ l->n_search_domains++;
+ break;
+
+ case DNS_SERVER_SYSTEM:
+ LIST_APPEND(domains, m->search_domains, d);
+ m->n_search_domains++;
+ break;
+
+ default:
+ assert_not_reached("Unknown search domain type");
+ }
+
+ d->linked = true;
+
+ if (ret)
+ *ret = d;
+
+ return 0;
+}
+
+DnsSearchDomain* dns_search_domain_ref(DnsSearchDomain *d) {
+ if (!d)
+ return NULL;
+
+ assert(d->n_ref > 0);
+ d->n_ref++;
+
+ return d;
+}
+
+DnsSearchDomain* dns_search_domain_unref(DnsSearchDomain *d) {
+ if (!d)
+ return NULL;
+
+ assert(d->n_ref > 0);
+ d->n_ref--;
+
+ if (d->n_ref > 0)
+ return NULL;
+
+ free(d->name);
+ free(d);
+
+ return NULL;
+}
+
+void dns_search_domain_unlink(DnsSearchDomain *d) {
+ assert(d);
+ assert(d->manager);
+
+ if (!d->linked)
+ return;
+
+ switch (d->type) {
+
+ case DNS_SEARCH_DOMAIN_LINK:
+ assert(d->link);
+ assert(d->link->n_search_domains > 0);
+ LIST_REMOVE(domains, d->link->search_domains, d);
+ d->link->n_search_domains--;
+ break;
+
+ case DNS_SEARCH_DOMAIN_SYSTEM:
+ assert(d->manager->n_search_domains > 0);
+ LIST_REMOVE(domains, d->manager->search_domains, d);
+ d->manager->n_search_domains--;
+ break;
+ }
+
+ d->linked = false;
+
+ dns_search_domain_unref(d);
+}
+
+void dns_search_domain_move_back_and_unmark(DnsSearchDomain *d) {
+ DnsSearchDomain *tail;
+
+ assert(d);
+
+ if (!d->marked)
+ return;
+
+ d->marked = false;
+
+ if (!d->linked || !d->domains_next)
+ return;
+
+ switch (d->type) {
+
+ case DNS_SEARCH_DOMAIN_LINK:
+ assert(d->link);
+ LIST_FIND_TAIL(domains, d, tail);
+ LIST_REMOVE(domains, d->link->search_domains, d);
+ LIST_INSERT_AFTER(domains, d->link->search_domains, tail, d);
+ break;
+
+ case DNS_SEARCH_DOMAIN_SYSTEM:
+ LIST_FIND_TAIL(domains, d, tail);
+ LIST_REMOVE(domains, d->manager->search_domains, d);
+ LIST_INSERT_AFTER(domains, d->manager->search_domains, tail, d);
+ break;
+
+ default:
+ assert_not_reached("Unknown search domain type");
+ }
+}
+
+void dns_search_domain_unlink_all(DnsSearchDomain *first) {
+ DnsSearchDomain *next;
+
+ if (!first)
+ return;
+
+ next = first->domains_next;
+ dns_search_domain_unlink(first);
+
+ dns_search_domain_unlink_all(next);
+}
+
+void dns_search_domain_unlink_marked(DnsSearchDomain *first) {
+ DnsSearchDomain *next;
+
+ if (!first)
+ return;
+
+ next = first->domains_next;
+
+ if (first->marked)
+ dns_search_domain_unlink(first);
+
+ dns_search_domain_unlink_marked(next);
+}
+
+void dns_search_domain_mark_all(DnsSearchDomain *first) {
+ if (!first)
+ return;
+
+ first->marked = true;
+ dns_search_domain_mark_all(first->domains_next);
+}
+
+int dns_search_domain_find(DnsSearchDomain *first, const char *name, DnsSearchDomain **ret) {
+ DnsSearchDomain *d;
+ int r;
+
+ assert(name);
+ assert(ret);
+
+ LIST_FOREACH(domains, d, first) {
+
+ r = dns_name_equal(name, d->name);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ *ret = d;
+ return 1;
+ }
+ }
+
+ *ret = NULL;
+ return 0;
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-search-domain.h b/src/grp-resolve/systemd-resolved/resolved-dns-search-domain.h
new file mode 100644
index 0000000000..53b4f3207a
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-search-domain.h
@@ -0,0 +1,74 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2015 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "systemd-basic/macro.h"
+
+typedef struct DnsSearchDomain DnsSearchDomain;
+
+typedef enum DnsSearchDomainType {
+ DNS_SEARCH_DOMAIN_SYSTEM,
+ DNS_SEARCH_DOMAIN_LINK,
+} DnsSearchDomainType;
+
+#include "resolved-link.h"
+#include "resolved-manager.h"
+
+struct DnsSearchDomain {
+ Manager *manager;
+
+ unsigned n_ref;
+
+ DnsSearchDomainType type;
+ Link *link;
+
+ char *name;
+
+ bool marked:1;
+ bool route_only:1;
+
+ bool linked:1;
+ LIST_FIELDS(DnsSearchDomain, domains);
+};
+
+int dns_search_domain_new(
+ Manager *m,
+ DnsSearchDomain **ret,
+ DnsSearchDomainType type,
+ Link *link,
+ const char *name);
+
+DnsSearchDomain* dns_search_domain_ref(DnsSearchDomain *d);
+DnsSearchDomain* dns_search_domain_unref(DnsSearchDomain *d);
+
+void dns_search_domain_unlink(DnsSearchDomain *d);
+void dns_search_domain_move_back_and_unmark(DnsSearchDomain *d);
+
+void dns_search_domain_unlink_all(DnsSearchDomain *first);
+void dns_search_domain_unlink_marked(DnsSearchDomain *first);
+void dns_search_domain_mark_all(DnsSearchDomain *first);
+
+int dns_search_domain_find(DnsSearchDomain *first, const char *name, DnsSearchDomain **ret);
+
+static inline const char* DNS_SEARCH_DOMAIN_NAME(DnsSearchDomain *d) {
+ return d ? d->name : NULL;
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(DnsSearchDomain*, dns_search_domain_unref);
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-server.c b/src/grp-resolve/systemd-resolved/resolved-dns-server.c
new file mode 100644
index 0000000000..2274eedae2
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-server.c
@@ -0,0 +1,778 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <systemd/sd-messages.h>
+
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/siphash24.h"
+#include "systemd-basic/string-table.h"
+#include "systemd-basic/string-util.h"
+
+#include "resolved-dns-server.h"
+#include "resolved-dns-stub.h"
+#include "resolved-resolv-conf.h"
+
+/* After how much time to repeat classic DNS requests */
+#define DNS_TIMEOUT_MIN_USEC (500 * USEC_PER_MSEC)
+#define DNS_TIMEOUT_MAX_USEC (5 * USEC_PER_SEC)
+
+/* The amount of time to wait before retrying with a full feature set */
+#define DNS_SERVER_FEATURE_GRACE_PERIOD_MAX_USEC (6 * USEC_PER_HOUR)
+#define DNS_SERVER_FEATURE_GRACE_PERIOD_MIN_USEC (5 * USEC_PER_MINUTE)
+
+/* The number of times we will attempt a certain feature set before degrading */
+#define DNS_SERVER_FEATURE_RETRY_ATTEMPTS 3
+
+int dns_server_new(
+ Manager *m,
+ DnsServer **ret,
+ DnsServerType type,
+ Link *l,
+ int family,
+ const union in_addr_union *in_addr,
+ int ifindex) {
+
+ DnsServer *s;
+
+ assert(m);
+ assert((type == DNS_SERVER_LINK) == !!l);
+ assert(in_addr);
+
+ if (!IN_SET(family, AF_INET, AF_INET6))
+ return -EAFNOSUPPORT;
+
+ if (l) {
+ if (l->n_dns_servers >= LINK_DNS_SERVERS_MAX)
+ return -E2BIG;
+ } else {
+ if (m->n_dns_servers >= MANAGER_DNS_SERVERS_MAX)
+ return -E2BIG;
+ }
+
+ s = new0(DnsServer, 1);
+ if (!s)
+ return -ENOMEM;
+
+ s->n_ref = 1;
+ s->manager = m;
+ s->verified_feature_level = _DNS_SERVER_FEATURE_LEVEL_INVALID;
+ s->possible_feature_level = DNS_SERVER_FEATURE_LEVEL_BEST;
+ s->features_grace_period_usec = DNS_SERVER_FEATURE_GRACE_PERIOD_MIN_USEC;
+ s->received_udp_packet_max = DNS_PACKET_UNICAST_SIZE_MAX;
+ s->type = type;
+ s->family = family;
+ s->address = *in_addr;
+ s->ifindex = ifindex;
+ s->resend_timeout = DNS_TIMEOUT_MIN_USEC;
+
+ switch (type) {
+
+ case DNS_SERVER_LINK:
+ s->link = l;
+ LIST_APPEND(servers, l->dns_servers, s);
+ l->n_dns_servers++;
+ break;
+
+ case DNS_SERVER_SYSTEM:
+ LIST_APPEND(servers, m->dns_servers, s);
+ m->n_dns_servers++;
+ break;
+
+ case DNS_SERVER_FALLBACK:
+ LIST_APPEND(servers, m->fallback_dns_servers, s);
+ m->n_dns_servers++;
+ break;
+
+ default:
+ assert_not_reached("Unknown server type");
+ }
+
+ s->linked = true;
+
+ /* A new DNS server that isn't fallback is added and the one
+ * we used so far was a fallback one? Then let's try to pick
+ * the new one */
+ if (type != DNS_SERVER_FALLBACK &&
+ m->current_dns_server &&
+ m->current_dns_server->type == DNS_SERVER_FALLBACK)
+ manager_set_dns_server(m, NULL);
+
+ if (ret)
+ *ret = s;
+
+ return 0;
+}
+
+DnsServer* dns_server_ref(DnsServer *s) {
+ if (!s)
+ return NULL;
+
+ assert(s->n_ref > 0);
+ s->n_ref++;
+
+ return s;
+}
+
+DnsServer* dns_server_unref(DnsServer *s) {
+ if (!s)
+ return NULL;
+
+ assert(s->n_ref > 0);
+ s->n_ref--;
+
+ if (s->n_ref > 0)
+ return NULL;
+
+ free(s->server_string);
+ free(s);
+ return NULL;
+}
+
+void dns_server_unlink(DnsServer *s) {
+ assert(s);
+ assert(s->manager);
+
+ /* This removes the specified server from the linked list of
+ * servers, but any server might still stay around if it has
+ * refs, for example from an ongoing transaction. */
+
+ if (!s->linked)
+ return;
+
+ switch (s->type) {
+
+ case DNS_SERVER_LINK:
+ assert(s->link);
+ assert(s->link->n_dns_servers > 0);
+ LIST_REMOVE(servers, s->link->dns_servers, s);
+ s->link->n_dns_servers--;
+ break;
+
+ case DNS_SERVER_SYSTEM:
+ assert(s->manager->n_dns_servers > 0);
+ LIST_REMOVE(servers, s->manager->dns_servers, s);
+ s->manager->n_dns_servers--;
+ break;
+
+ case DNS_SERVER_FALLBACK:
+ assert(s->manager->n_dns_servers > 0);
+ LIST_REMOVE(servers, s->manager->fallback_dns_servers, s);
+ s->manager->n_dns_servers--;
+ break;
+ }
+
+ s->linked = false;
+
+ if (s->link && s->link->current_dns_server == s)
+ link_set_dns_server(s->link, NULL);
+
+ if (s->manager->current_dns_server == s)
+ manager_set_dns_server(s->manager, NULL);
+
+ dns_server_unref(s);
+}
+
+void dns_server_move_back_and_unmark(DnsServer *s) {
+ DnsServer *tail;
+
+ assert(s);
+
+ if (!s->marked)
+ return;
+
+ s->marked = false;
+
+ if (!s->linked || !s->servers_next)
+ return;
+
+ /* Move us to the end of the list, so that the order is
+ * strictly kept, if we are not at the end anyway. */
+
+ switch (s->type) {
+
+ case DNS_SERVER_LINK:
+ assert(s->link);
+ LIST_FIND_TAIL(servers, s, tail);
+ LIST_REMOVE(servers, s->link->dns_servers, s);
+ LIST_INSERT_AFTER(servers, s->link->dns_servers, tail, s);
+ break;
+
+ case DNS_SERVER_SYSTEM:
+ LIST_FIND_TAIL(servers, s, tail);
+ LIST_REMOVE(servers, s->manager->dns_servers, s);
+ LIST_INSERT_AFTER(servers, s->manager->dns_servers, tail, s);
+ break;
+
+ case DNS_SERVER_FALLBACK:
+ LIST_FIND_TAIL(servers, s, tail);
+ LIST_REMOVE(servers, s->manager->fallback_dns_servers, s);
+ LIST_INSERT_AFTER(servers, s->manager->fallback_dns_servers, tail, s);
+ break;
+
+ default:
+ assert_not_reached("Unknown server type");
+ }
+}
+
+static void dns_server_verified(DnsServer *s, DnsServerFeatureLevel level) {
+ assert(s);
+
+ if (s->verified_feature_level > level)
+ return;
+
+ if (s->verified_feature_level != level) {
+ log_debug("Verified we get a response at feature level %s from DNS server %s.",
+ dns_server_feature_level_to_string(level),
+ dns_server_string(s));
+ s->verified_feature_level = level;
+ }
+
+ assert_se(sd_event_now(s->manager->event, clock_boottime_or_monotonic(), &s->verified_usec) >= 0);
+}
+
+static void dns_server_reset_counters(DnsServer *s) {
+ assert(s);
+
+ s->n_failed_udp = 0;
+ s->n_failed_tcp = 0;
+ s->packet_truncated = false;
+ s->verified_usec = 0;
+
+ /* Note that we do not reset s->packet_bad_opt and s->packet_rrsig_missing here. We reset them only when the
+ * grace period ends, but not when lowering the possible feature level, as a lower level feature level should
+ * not make RRSIGs appear or OPT appear, but rather make them disappear. If the reappear anyway, then that's
+ * indication for a differently broken OPT/RRSIG implementation, and we really don't want to support that
+ * either.
+ *
+ * This is particularly important to deal with certain Belkin routers which break OPT for certain lookups (A),
+ * but pass traffic through for others (AAAA). If we detect the broken behaviour on one lookup we should not
+ * reenable it for another, because we cannot validate things anyway, given that the RRSIG/OPT data will be
+ * incomplete. */
+}
+
+void dns_server_packet_received(DnsServer *s, int protocol, DnsServerFeatureLevel level, usec_t rtt, size_t size) {
+ assert(s);
+
+ if (protocol == IPPROTO_UDP) {
+ if (s->possible_feature_level == level)
+ s->n_failed_udp = 0;
+
+ /* If the RRSIG data is missing, then we can only validate EDNS0 at max */
+ if (s->packet_rrsig_missing && level >= DNS_SERVER_FEATURE_LEVEL_DO)
+ level = DNS_SERVER_FEATURE_LEVEL_DO - 1;
+
+ /* If the OPT RR got lost, then we can only validate UDP at max */
+ if (s->packet_bad_opt && level >= DNS_SERVER_FEATURE_LEVEL_EDNS0)
+ level = DNS_SERVER_FEATURE_LEVEL_EDNS0 - 1;
+
+ /* Even if we successfully receive a reply to a request announcing support for large packets,
+ that does not mean we can necessarily receive large packets. */
+ if (level == DNS_SERVER_FEATURE_LEVEL_LARGE)
+ level = DNS_SERVER_FEATURE_LEVEL_LARGE - 1;
+
+ } else if (protocol == IPPROTO_TCP) {
+
+ if (s->possible_feature_level == level)
+ s->n_failed_tcp = 0;
+
+ /* Successful TCP connections are only useful to verify the TCP feature level. */
+ level = DNS_SERVER_FEATURE_LEVEL_TCP;
+ }
+
+ dns_server_verified(s, level);
+
+ /* Remember the size of the largest UDP packet we received from a server,
+ we know that we can always announce support for packets with at least
+ this size. */
+ if (protocol == IPPROTO_UDP && s->received_udp_packet_max < size)
+ s->received_udp_packet_max = size;
+
+ if (s->max_rtt < rtt) {
+ s->max_rtt = rtt;
+ s->resend_timeout = CLAMP(s->max_rtt * 2, DNS_TIMEOUT_MIN_USEC, DNS_TIMEOUT_MAX_USEC);
+ }
+}
+
+void dns_server_packet_lost(DnsServer *s, int protocol, DnsServerFeatureLevel level, usec_t usec) {
+ assert(s);
+ assert(s->manager);
+
+ if (s->possible_feature_level == level) {
+ if (protocol == IPPROTO_UDP)
+ s->n_failed_udp++;
+ else if (protocol == IPPROTO_TCP)
+ s->n_failed_tcp++;
+ }
+
+ if (s->resend_timeout > usec)
+ return;
+
+ s->resend_timeout = MIN(s->resend_timeout * 2, DNS_TIMEOUT_MAX_USEC);
+}
+
+void dns_server_packet_truncated(DnsServer *s, DnsServerFeatureLevel level) {
+ assert(s);
+
+ /* Invoked whenever we get a packet with TC bit set. */
+
+ if (s->possible_feature_level != level)
+ return;
+
+ s->packet_truncated = true;
+}
+
+void dns_server_packet_rrsig_missing(DnsServer *s, DnsServerFeatureLevel level) {
+ assert(s);
+
+ if (level < DNS_SERVER_FEATURE_LEVEL_DO)
+ return;
+
+ /* If the RRSIG RRs are missing, we have to downgrade what we previously verified */
+ if (s->verified_feature_level >= DNS_SERVER_FEATURE_LEVEL_DO)
+ s->verified_feature_level = DNS_SERVER_FEATURE_LEVEL_DO-1;
+
+ s->packet_rrsig_missing = true;
+}
+
+void dns_server_packet_bad_opt(DnsServer *s, DnsServerFeatureLevel level) {
+ assert(s);
+
+ if (level < DNS_SERVER_FEATURE_LEVEL_EDNS0)
+ return;
+
+ /* If the OPT RR got lost, we have to downgrade what we previously verified */
+ if (s->verified_feature_level >= DNS_SERVER_FEATURE_LEVEL_EDNS0)
+ s->verified_feature_level = DNS_SERVER_FEATURE_LEVEL_EDNS0-1;
+
+ s->packet_bad_opt = true;
+}
+
+void dns_server_packet_rcode_downgrade(DnsServer *s, DnsServerFeatureLevel level) {
+ assert(s);
+
+ /* Invoked whenever we got a FORMERR, SERVFAIL or NOTIMP rcode from a server and downgrading the feature level
+ * for the transaction made it go away. In this case we immediately downgrade to the feature level that made
+ * things work. */
+
+ if (s->verified_feature_level > level)
+ s->verified_feature_level = level;
+
+ if (s->possible_feature_level > level) {
+ s->possible_feature_level = level;
+ dns_server_reset_counters(s);
+ }
+
+ log_debug("Downgrading transaction feature level fixed an RCODE error, downgrading server %s too.", dns_server_string(s));
+}
+
+static bool dns_server_grace_period_expired(DnsServer *s) {
+ usec_t ts;
+
+ assert(s);
+ assert(s->manager);
+
+ if (s->verified_usec == 0)
+ return false;
+
+ assert_se(sd_event_now(s->manager->event, clock_boottime_or_monotonic(), &ts) >= 0);
+
+ if (s->verified_usec + s->features_grace_period_usec > ts)
+ return false;
+
+ s->features_grace_period_usec = MIN(s->features_grace_period_usec * 2, DNS_SERVER_FEATURE_GRACE_PERIOD_MAX_USEC);
+
+ return true;
+}
+
+DnsServerFeatureLevel dns_server_possible_feature_level(DnsServer *s) {
+ assert(s);
+
+ if (s->possible_feature_level != DNS_SERVER_FEATURE_LEVEL_BEST &&
+ dns_server_grace_period_expired(s)) {
+
+ s->possible_feature_level = DNS_SERVER_FEATURE_LEVEL_BEST;
+
+ dns_server_reset_counters(s);
+
+ s->packet_bad_opt = false;
+ s->packet_rrsig_missing = false;
+
+ log_info("Grace period over, resuming full feature set (%s) for DNS server %s.",
+ dns_server_feature_level_to_string(s->possible_feature_level),
+ dns_server_string(s));
+
+ } else if (s->possible_feature_level <= s->verified_feature_level)
+ s->possible_feature_level = s->verified_feature_level;
+ else {
+ DnsServerFeatureLevel p = s->possible_feature_level;
+
+ if (s->n_failed_tcp >= DNS_SERVER_FEATURE_RETRY_ATTEMPTS &&
+ s->possible_feature_level == DNS_SERVER_FEATURE_LEVEL_TCP) {
+
+ /* We are at the TCP (lowest) level, and we tried a couple of TCP connections, and it didn't
+ * work. Upgrade back to UDP again. */
+ log_debug("Reached maximum number of failed TCP connection attempts, trying UDP again...");
+ s->possible_feature_level = DNS_SERVER_FEATURE_LEVEL_UDP;
+
+ } else if (s->packet_bad_opt &&
+ s->possible_feature_level >= DNS_SERVER_FEATURE_LEVEL_EDNS0) {
+
+ /* A reply to one of our EDNS0 queries didn't carry a valid OPT RR, then downgrade to below
+ * EDNS0 levels. After all, some records generate different responses with and without OPT RR
+ * in the request. Example:
+ * https://open.nlnetlabs.nl/pipermail/dnssec-trigger/2014-November/000376.html */
+
+ log_debug("Server doesn't support EDNS(0) properly, downgrading feature level...");
+ s->possible_feature_level = DNS_SERVER_FEATURE_LEVEL_UDP;
+
+ } else if (s->packet_rrsig_missing &&
+ s->possible_feature_level >= DNS_SERVER_FEATURE_LEVEL_DO) {
+
+ /* RRSIG data was missing on a EDNS0 packet with DO bit set. This means the server doesn't
+ * augment responses with DNSSEC RRs. If so, let's better not ask the server for it anymore,
+ * after all some servers generate different replies depending if an OPT RR is in the query or
+ * not. */
+
+ log_debug("Detected server responses lack RRSIG records, downgrading feature level...");
+ s->possible_feature_level = DNS_SERVER_FEATURE_LEVEL_EDNS0;
+
+ } else if (s->n_failed_udp >= DNS_SERVER_FEATURE_RETRY_ATTEMPTS &&
+ s->possible_feature_level >= DNS_SERVER_FEATURE_LEVEL_UDP) {
+
+ /* We lost too many UDP packets in a row, and are on a feature level of UDP or higher. If the
+ * packets are lost, maybe the server cannot parse them, hence downgrading sounds like a good
+ * idea. We might downgrade all the way down to TCP this way. */
+
+ log_debug("Lost too many UDP packets, downgrading feature level...");
+ s->possible_feature_level--;
+
+ } else if (s->n_failed_tcp >= DNS_SERVER_FEATURE_RETRY_ATTEMPTS &&
+ s->packet_truncated &&
+ s->possible_feature_level > DNS_SERVER_FEATURE_LEVEL_UDP) {
+
+ /* We got too many TCP connection failures in a row, we had at least one truncated packet, and
+ * are on a feature level above UDP. By downgrading things and getting rid of DNSSEC or EDNS0
+ * data we hope to make the packet smaller, so that it still works via UDP given that TCP
+ * appears not to be a fallback. Note that if we are already at the lowest UDP level, we don't
+ * go further down, since that's TCP, and TCP failed too often after all. */
+
+ log_debug("Got too many failed TCP connection failures and truncated UDP packets, downgrading feature level...");
+ s->possible_feature_level--;
+ }
+
+ if (p != s->possible_feature_level) {
+
+ /* We changed the feature level, reset the counting */
+ dns_server_reset_counters(s);
+
+ log_warning("Using degraded feature set (%s) for DNS server %s.",
+ dns_server_feature_level_to_string(s->possible_feature_level),
+ dns_server_string(s));
+ }
+ }
+
+ return s->possible_feature_level;
+}
+
+int dns_server_adjust_opt(DnsServer *server, DnsPacket *packet, DnsServerFeatureLevel level) {
+ size_t packet_size;
+ bool edns_do;
+ int r;
+
+ assert(server);
+ assert(packet);
+ assert(packet->protocol == DNS_PROTOCOL_DNS);
+
+ /* Fix the OPT field in the packet to match our current feature level. */
+
+ r = dns_packet_truncate_opt(packet);
+ if (r < 0)
+ return r;
+
+ if (level < DNS_SERVER_FEATURE_LEVEL_EDNS0)
+ return 0;
+
+ edns_do = level >= DNS_SERVER_FEATURE_LEVEL_DO;
+
+ if (level >= DNS_SERVER_FEATURE_LEVEL_LARGE)
+ packet_size = DNS_PACKET_UNICAST_SIZE_LARGE_MAX;
+ else
+ packet_size = server->received_udp_packet_max;
+
+ return dns_packet_append_opt(packet, packet_size, edns_do, 0, NULL);
+}
+
+int dns_server_ifindex(const DnsServer *s) {
+ assert(s);
+
+ /* The link ifindex always takes precedence */
+ if (s->link)
+ return s->link->ifindex;
+
+ if (s->ifindex > 0)
+ return s->ifindex;
+
+ return 0;
+}
+
+const char *dns_server_string(DnsServer *server) {
+ assert(server);
+
+ if (!server->server_string)
+ (void) in_addr_ifindex_to_string(server->family, &server->address, dns_server_ifindex(server), &server->server_string);
+
+ return strna(server->server_string);
+}
+
+bool dns_server_dnssec_supported(DnsServer *server) {
+ assert(server);
+
+ /* Returns whether the server supports DNSSEC according to what we know about it */
+
+ if (server->possible_feature_level < DNS_SERVER_FEATURE_LEVEL_DO)
+ return false;
+
+ if (server->packet_bad_opt)
+ return false;
+
+ if (server->packet_rrsig_missing)
+ return false;
+
+ /* DNSSEC servers need to support TCP properly (see RFC5966), if they don't, we assume DNSSEC is borked too */
+ if (server->n_failed_tcp >= DNS_SERVER_FEATURE_RETRY_ATTEMPTS)
+ return false;
+
+ return true;
+}
+
+void dns_server_warn_downgrade(DnsServer *server) {
+ assert(server);
+
+ if (server->warned_downgrade)
+ return;
+
+ log_struct(LOG_NOTICE,
+ LOG_MESSAGE_ID(SD_MESSAGE_DNSSEC_DOWNGRADE),
+ LOG_MESSAGE("Server %s does not support DNSSEC, downgrading to non-DNSSEC mode.", dns_server_string(server)),
+ "DNS_SERVER=%s", dns_server_string(server),
+ "DNS_SERVER_FEATURE_LEVEL=%s", dns_server_feature_level_to_string(server->possible_feature_level),
+ NULL);
+
+ server->warned_downgrade = true;
+}
+
+static void dns_server_hash_func(const void *p, struct siphash *state) {
+ const DnsServer *s = p;
+
+ assert(s);
+
+ siphash24_compress(&s->family, sizeof(s->family), state);
+ siphash24_compress(&s->address, FAMILY_ADDRESS_SIZE(s->family), state);
+ siphash24_compress(&s->ifindex, sizeof(s->ifindex), state);
+}
+
+static int dns_server_compare_func(const void *a, const void *b) {
+ const DnsServer *x = a, *y = b;
+ int r;
+
+ if (x->family < y->family)
+ return -1;
+ if (x->family > y->family)
+ return 1;
+
+ r = memcmp(&x->address, &y->address, FAMILY_ADDRESS_SIZE(x->family));
+ if (r != 0)
+ return r;
+
+ if (x->ifindex < y->ifindex)
+ return -1;
+ if (x->ifindex > y->ifindex)
+ return 1;
+
+ return 0;
+}
+
+const struct hash_ops dns_server_hash_ops = {
+ .hash = dns_server_hash_func,
+ .compare = dns_server_compare_func
+};
+
+void dns_server_unlink_all(DnsServer *first) {
+ DnsServer *next;
+
+ if (!first)
+ return;
+
+ next = first->servers_next;
+ dns_server_unlink(first);
+
+ dns_server_unlink_all(next);
+}
+
+void dns_server_unlink_marked(DnsServer *first) {
+ DnsServer *next;
+
+ if (!first)
+ return;
+
+ next = first->servers_next;
+
+ if (first->marked)
+ dns_server_unlink(first);
+
+ dns_server_unlink_marked(next);
+}
+
+void dns_server_mark_all(DnsServer *first) {
+ if (!first)
+ return;
+
+ first->marked = true;
+ dns_server_mark_all(first->servers_next);
+}
+
+DnsServer *dns_server_find(DnsServer *first, int family, const union in_addr_union *in_addr, int ifindex) {
+ DnsServer *s;
+
+ LIST_FOREACH(servers, s, first)
+ if (s->family == family && in_addr_equal(family, &s->address, in_addr) > 0 && s->ifindex == ifindex)
+ return s;
+
+ return NULL;
+}
+
+DnsServer *manager_get_first_dns_server(Manager *m, DnsServerType t) {
+ assert(m);
+
+ switch (t) {
+
+ case DNS_SERVER_SYSTEM:
+ return m->dns_servers;
+
+ case DNS_SERVER_FALLBACK:
+ return m->fallback_dns_servers;
+
+ default:
+ return NULL;
+ }
+}
+
+DnsServer *manager_set_dns_server(Manager *m, DnsServer *s) {
+ assert(m);
+
+ if (m->current_dns_server == s)
+ return s;
+
+ if (s)
+ log_info("Switching to %s DNS server %s.",
+ dns_server_type_to_string(s->type),
+ dns_server_string(s));
+
+ dns_server_unref(m->current_dns_server);
+ m->current_dns_server = dns_server_ref(s);
+
+ if (m->unicast_scope)
+ dns_cache_flush(&m->unicast_scope->cache);
+
+ return s;
+}
+
+DnsServer *manager_get_dns_server(Manager *m) {
+ Link *l;
+ assert(m);
+
+ /* Try to read updates resolv.conf */
+ manager_read_resolv_conf(m);
+
+ /* If no DNS server was chosen so far, pick the first one */
+ if (!m->current_dns_server)
+ manager_set_dns_server(m, m->dns_servers);
+
+ if (!m->current_dns_server) {
+ bool found = false;
+ Iterator i;
+
+ /* No DNS servers configured, let's see if there are
+ * any on any links. If not, we use the fallback
+ * servers */
+
+ HASHMAP_FOREACH(l, m->links, i)
+ if (l->dns_servers) {
+ found = true;
+ break;
+ }
+
+ if (!found)
+ manager_set_dns_server(m, m->fallback_dns_servers);
+ }
+
+ return m->current_dns_server;
+}
+
+void manager_next_dns_server(Manager *m) {
+ assert(m);
+
+ /* If there's currently no DNS server set, then the next
+ * manager_get_dns_server() will find one */
+ if (!m->current_dns_server)
+ return;
+
+ /* Change to the next one, but make sure to follow the linked
+ * list only if the server is still linked. */
+ if (m->current_dns_server->linked && m->current_dns_server->servers_next) {
+ manager_set_dns_server(m, m->current_dns_server->servers_next);
+ return;
+ }
+
+ /* If there was no next one, then start from the beginning of
+ * the list */
+ if (m->current_dns_server->type == DNS_SERVER_FALLBACK)
+ manager_set_dns_server(m, m->fallback_dns_servers);
+ else
+ manager_set_dns_server(m, m->dns_servers);
+}
+
+bool dns_server_address_valid(int family, const union in_addr_union *sa) {
+
+ /* Refuses the 0 IP addresses as well as 127.0.0.53 (which is our own DNS stub) */
+
+ if (in_addr_is_null(family, sa))
+ return false;
+
+ if (family == AF_INET && sa->in.s_addr == htobe32(INADDR_DNS_STUB))
+ return false;
+
+ return true;
+}
+
+static const char* const dns_server_type_table[_DNS_SERVER_TYPE_MAX] = {
+ [DNS_SERVER_SYSTEM] = "system",
+ [DNS_SERVER_FALLBACK] = "fallback",
+ [DNS_SERVER_LINK] = "link",
+};
+DEFINE_STRING_TABLE_LOOKUP(dns_server_type, DnsServerType);
+
+static const char* const dns_server_feature_level_table[_DNS_SERVER_FEATURE_LEVEL_MAX] = {
+ [DNS_SERVER_FEATURE_LEVEL_TCP] = "TCP",
+ [DNS_SERVER_FEATURE_LEVEL_UDP] = "UDP",
+ [DNS_SERVER_FEATURE_LEVEL_EDNS0] = "UDP+EDNS0",
+ [DNS_SERVER_FEATURE_LEVEL_DO] = "UDP+EDNS0+DO",
+ [DNS_SERVER_FEATURE_LEVEL_LARGE] = "UDP+EDNS0+DO+LARGE",
+};
+DEFINE_STRING_TABLE_LOOKUP(dns_server_feature_level, DnsServerFeatureLevel);
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-server.h b/src/grp-resolve/systemd-resolved/resolved-dns-server.h
new file mode 100644
index 0000000000..327bc7ae0a
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-server.h
@@ -0,0 +1,147 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "systemd-basic/in-addr-util.h"
+
+typedef struct DnsServer DnsServer;
+
+typedef enum DnsServerType {
+ DNS_SERVER_SYSTEM,
+ DNS_SERVER_FALLBACK,
+ DNS_SERVER_LINK,
+} DnsServerType;
+#define _DNS_SERVER_TYPE_MAX (DNS_SERVER_LINK + 1)
+
+const char* dns_server_type_to_string(DnsServerType i) _const_;
+DnsServerType dns_server_type_from_string(const char *s) _pure_;
+
+typedef enum DnsServerFeatureLevel {
+ DNS_SERVER_FEATURE_LEVEL_TCP,
+ DNS_SERVER_FEATURE_LEVEL_UDP,
+ DNS_SERVER_FEATURE_LEVEL_EDNS0,
+ DNS_SERVER_FEATURE_LEVEL_DO,
+ DNS_SERVER_FEATURE_LEVEL_LARGE,
+ _DNS_SERVER_FEATURE_LEVEL_MAX,
+ _DNS_SERVER_FEATURE_LEVEL_INVALID = -1
+} DnsServerFeatureLevel;
+
+#define DNS_SERVER_FEATURE_LEVEL_WORST 0
+#define DNS_SERVER_FEATURE_LEVEL_BEST (_DNS_SERVER_FEATURE_LEVEL_MAX - 1)
+
+const char* dns_server_feature_level_to_string(int i) _const_;
+int dns_server_feature_level_from_string(const char *s) _pure_;
+
+#include "resolved-link.h"
+#include "resolved-manager.h"
+
+struct DnsServer {
+ Manager *manager;
+
+ unsigned n_ref;
+
+ DnsServerType type;
+ Link *link;
+
+ int family;
+ union in_addr_union address;
+ int ifindex; /* for IPv6 link-local DNS servers */
+
+ char *server_string;
+
+ usec_t resend_timeout;
+ usec_t max_rtt;
+
+ DnsServerFeatureLevel verified_feature_level;
+ DnsServerFeatureLevel possible_feature_level;
+
+ size_t received_udp_packet_max;
+
+ unsigned n_failed_udp;
+ unsigned n_failed_tcp;
+
+ bool packet_truncated:1;
+ bool packet_bad_opt:1;
+ bool packet_rrsig_missing:1;
+
+ usec_t verified_usec;
+ usec_t features_grace_period_usec;
+
+ /* Whether we already warned about downgrading to non-DNSSEC mode for this server */
+ bool warned_downgrade:1;
+
+ /* Used when GC'ing old DNS servers when configuration changes. */
+ bool marked:1;
+
+ /* If linked is set, then this server appears in the servers linked list */
+ bool linked:1;
+ LIST_FIELDS(DnsServer, servers);
+};
+
+int dns_server_new(
+ Manager *m,
+ DnsServer **ret,
+ DnsServerType type,
+ Link *link,
+ int family,
+ const union in_addr_union *address,
+ int ifindex);
+
+DnsServer* dns_server_ref(DnsServer *s);
+DnsServer* dns_server_unref(DnsServer *s);
+
+void dns_server_unlink(DnsServer *s);
+void dns_server_move_back_and_unmark(DnsServer *s);
+
+void dns_server_packet_received(DnsServer *s, int protocol, DnsServerFeatureLevel level, usec_t rtt, size_t size);
+void dns_server_packet_lost(DnsServer *s, int protocol, DnsServerFeatureLevel level, usec_t usec);
+void dns_server_packet_truncated(DnsServer *s, DnsServerFeatureLevel level);
+void dns_server_packet_rrsig_missing(DnsServer *s, DnsServerFeatureLevel level);
+void dns_server_packet_bad_opt(DnsServer *s, DnsServerFeatureLevel level);
+void dns_server_packet_rcode_downgrade(DnsServer *s, DnsServerFeatureLevel level);
+
+DnsServerFeatureLevel dns_server_possible_feature_level(DnsServer *s);
+
+int dns_server_adjust_opt(DnsServer *server, DnsPacket *packet, DnsServerFeatureLevel level);
+
+const char *dns_server_string(DnsServer *server);
+int dns_server_ifindex(const DnsServer *s);
+
+bool dns_server_dnssec_supported(DnsServer *server);
+
+void dns_server_warn_downgrade(DnsServer *server);
+
+DnsServer *dns_server_find(DnsServer *first, int family, const union in_addr_union *in_addr, int ifindex);
+
+void dns_server_unlink_all(DnsServer *first);
+void dns_server_unlink_marked(DnsServer *first);
+void dns_server_mark_all(DnsServer *first);
+
+DnsServer *manager_get_first_dns_server(Manager *m, DnsServerType t);
+
+DnsServer *manager_set_dns_server(Manager *m, DnsServer *s);
+DnsServer *manager_get_dns_server(Manager *m);
+void manager_next_dns_server(Manager *m);
+
+bool dns_server_address_valid(int family, const union in_addr_union *sa);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(DnsServer*, dns_server_unref);
+
+extern const struct hash_ops dns_server_hash_ops;
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-stream.c b/src/grp-resolve/systemd-resolved/resolved-dns-stream.c
new file mode 100644
index 0000000000..353d5f7a45
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-stream.c
@@ -0,0 +1,421 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <netinet/tcp.h>
+
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/fd-util.h"
+#include "systemd-basic/io-util.h"
+#include "systemd-basic/missing.h"
+
+#include "resolved-dns-stream.h"
+
+#define DNS_STREAM_TIMEOUT_USEC (10 * USEC_PER_SEC)
+#define DNS_STREAMS_MAX 128
+
+static void dns_stream_stop(DnsStream *s) {
+ assert(s);
+
+ s->io_event_source = sd_event_source_unref(s->io_event_source);
+ s->timeout_event_source = sd_event_source_unref(s->timeout_event_source);
+ s->fd = safe_close(s->fd);
+}
+
+static int dns_stream_update_io(DnsStream *s) {
+ int f = 0;
+
+ assert(s);
+
+ if (s->write_packet && s->n_written < sizeof(s->write_size) + s->write_packet->size)
+ f |= EPOLLOUT;
+ if (!s->read_packet || s->n_read < sizeof(s->read_size) + s->read_packet->size)
+ f |= EPOLLIN;
+
+ return sd_event_source_set_io_events(s->io_event_source, f);
+}
+
+static int dns_stream_complete(DnsStream *s, int error) {
+ assert(s);
+
+ dns_stream_stop(s);
+
+ if (s->complete)
+ s->complete(s, error);
+ else /* the default action if no completion function is set is to close the stream */
+ dns_stream_unref(s);
+
+ return 0;
+}
+
+static int dns_stream_identify(DnsStream *s) {
+ union {
+ struct cmsghdr header; /* For alignment */
+ uint8_t buffer[CMSG_SPACE(MAXSIZE(struct in_pktinfo, struct in6_pktinfo))
+ + EXTRA_CMSG_SPACE /* kernel appears to require extra space */];
+ } control;
+ struct msghdr mh = {};
+ struct cmsghdr *cmsg;
+ socklen_t sl;
+ int r;
+
+ assert(s);
+
+ if (s->identified)
+ return 0;
+
+ /* Query the local side */
+ s->local_salen = sizeof(s->local);
+ r = getsockname(s->fd, &s->local.sa, &s->local_salen);
+ if (r < 0)
+ return -errno;
+ if (s->local.sa.sa_family == AF_INET6 && s->ifindex <= 0)
+ s->ifindex = s->local.in6.sin6_scope_id;
+
+ /* Query the remote side */
+ s->peer_salen = sizeof(s->peer);
+ r = getpeername(s->fd, &s->peer.sa, &s->peer_salen);
+ if (r < 0)
+ return -errno;
+ if (s->peer.sa.sa_family == AF_INET6 && s->ifindex <= 0)
+ s->ifindex = s->peer.in6.sin6_scope_id;
+
+ /* Check consistency */
+ assert(s->peer.sa.sa_family == s->local.sa.sa_family);
+ assert(IN_SET(s->peer.sa.sa_family, AF_INET, AF_INET6));
+
+ /* Query connection meta information */
+ sl = sizeof(control);
+ if (s->peer.sa.sa_family == AF_INET) {
+ r = getsockopt(s->fd, IPPROTO_IP, IP_PKTOPTIONS, &control, &sl);
+ if (r < 0)
+ return -errno;
+ } else if (s->peer.sa.sa_family == AF_INET6) {
+
+ r = getsockopt(s->fd, IPPROTO_IPV6, IPV6_2292PKTOPTIONS, &control, &sl);
+ if (r < 0)
+ return -errno;
+ } else
+ return -EAFNOSUPPORT;
+
+ mh.msg_control = &control;
+ mh.msg_controllen = sl;
+
+ CMSG_FOREACH(cmsg, &mh) {
+
+ if (cmsg->cmsg_level == IPPROTO_IPV6) {
+ assert(s->peer.sa.sa_family == AF_INET6);
+
+ switch (cmsg->cmsg_type) {
+
+ case IPV6_PKTINFO: {
+ struct in6_pktinfo *i = (struct in6_pktinfo*) CMSG_DATA(cmsg);
+
+ if (s->ifindex <= 0)
+ s->ifindex = i->ipi6_ifindex;
+ break;
+ }
+
+ case IPV6_HOPLIMIT:
+ s->ttl = *(int *) CMSG_DATA(cmsg);
+ break;
+ }
+
+ } else if (cmsg->cmsg_level == IPPROTO_IP) {
+ assert(s->peer.sa.sa_family == AF_INET);
+
+ switch (cmsg->cmsg_type) {
+
+ case IP_PKTINFO: {
+ struct in_pktinfo *i = (struct in_pktinfo*) CMSG_DATA(cmsg);
+
+ if (s->ifindex <= 0)
+ s->ifindex = i->ipi_ifindex;
+ break;
+ }
+
+ case IP_TTL:
+ s->ttl = *(int *) CMSG_DATA(cmsg);
+ break;
+ }
+ }
+ }
+
+ /* The Linux kernel sets the interface index to the loopback
+ * device if the connection came from the local host since it
+ * avoids the routing table in such a case. Let's unset the
+ * interface index in such a case. */
+ if (s->ifindex == LOOPBACK_IFINDEX)
+ s->ifindex = 0;
+
+ /* If we don't know the interface index still, we look for the
+ * first local interface with a matching address. Yuck! */
+ if (s->ifindex <= 0)
+ s->ifindex = manager_find_ifindex(s->manager, s->local.sa.sa_family, s->local.sa.sa_family == AF_INET ? (union in_addr_union*) &s->local.in.sin_addr : (union in_addr_union*) &s->local.in6.sin6_addr);
+
+ if (s->protocol == DNS_PROTOCOL_LLMNR && s->ifindex > 0) {
+ uint32_t ifindex = htobe32(s->ifindex);
+
+ /* Make sure all packets for this connection are sent on the same interface */
+ if (s->local.sa.sa_family == AF_INET) {
+ r = setsockopt(s->fd, IPPROTO_IP, IP_UNICAST_IF, &ifindex, sizeof(ifindex));
+ if (r < 0)
+ log_debug_errno(errno, "Failed to invoke IP_UNICAST_IF: %m");
+ } else if (s->local.sa.sa_family == AF_INET6) {
+ r = setsockopt(s->fd, IPPROTO_IPV6, IPV6_UNICAST_IF, &ifindex, sizeof(ifindex));
+ if (r < 0)
+ log_debug_errno(errno, "Failed to invoke IPV6_UNICAST_IF: %m");
+ }
+ }
+
+ s->identified = true;
+
+ return 0;
+}
+
+static int on_stream_timeout(sd_event_source *es, usec_t usec, void *userdata) {
+ DnsStream *s = userdata;
+
+ assert(s);
+
+ return dns_stream_complete(s, ETIMEDOUT);
+}
+
+static int on_stream_io(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
+ DnsStream *s = userdata;
+ int r;
+
+ assert(s);
+
+ r = dns_stream_identify(s);
+ if (r < 0)
+ return dns_stream_complete(s, -r);
+
+ if ((revents & EPOLLOUT) &&
+ s->write_packet &&
+ s->n_written < sizeof(s->write_size) + s->write_packet->size) {
+
+ struct iovec iov[2];
+ ssize_t ss;
+
+ iov[0].iov_base = &s->write_size;
+ iov[0].iov_len = sizeof(s->write_size);
+ iov[1].iov_base = DNS_PACKET_DATA(s->write_packet);
+ iov[1].iov_len = s->write_packet->size;
+
+ IOVEC_INCREMENT(iov, 2, s->n_written);
+
+ ss = writev(fd, iov, 2);
+ if (ss < 0) {
+ if (errno != EINTR && errno != EAGAIN)
+ return dns_stream_complete(s, errno);
+ } else
+ s->n_written += ss;
+
+ /* Are we done? If so, disable the event source for EPOLLOUT */
+ if (s->n_written >= sizeof(s->write_size) + s->write_packet->size) {
+ r = dns_stream_update_io(s);
+ if (r < 0)
+ return dns_stream_complete(s, -r);
+ }
+ }
+
+ if ((revents & (EPOLLIN|EPOLLHUP|EPOLLRDHUP)) &&
+ (!s->read_packet ||
+ s->n_read < sizeof(s->read_size) + s->read_packet->size)) {
+
+ if (s->n_read < sizeof(s->read_size)) {
+ ssize_t ss;
+
+ ss = read(fd, (uint8_t*) &s->read_size + s->n_read, sizeof(s->read_size) - s->n_read);
+ if (ss < 0) {
+ if (errno != EINTR && errno != EAGAIN)
+ return dns_stream_complete(s, errno);
+ } else if (ss == 0)
+ return dns_stream_complete(s, ECONNRESET);
+ else
+ s->n_read += ss;
+ }
+
+ if (s->n_read >= sizeof(s->read_size)) {
+
+ if (be16toh(s->read_size) < DNS_PACKET_HEADER_SIZE)
+ return dns_stream_complete(s, EBADMSG);
+
+ if (s->n_read < sizeof(s->read_size) + be16toh(s->read_size)) {
+ ssize_t ss;
+
+ if (!s->read_packet) {
+ r = dns_packet_new(&s->read_packet, s->protocol, be16toh(s->read_size));
+ if (r < 0)
+ return dns_stream_complete(s, -r);
+
+ s->read_packet->size = be16toh(s->read_size);
+ s->read_packet->ipproto = IPPROTO_TCP;
+ s->read_packet->family = s->peer.sa.sa_family;
+ s->read_packet->ttl = s->ttl;
+ s->read_packet->ifindex = s->ifindex;
+
+ if (s->read_packet->family == AF_INET) {
+ s->read_packet->sender.in = s->peer.in.sin_addr;
+ s->read_packet->sender_port = be16toh(s->peer.in.sin_port);
+ s->read_packet->destination.in = s->local.in.sin_addr;
+ s->read_packet->destination_port = be16toh(s->local.in.sin_port);
+ } else {
+ assert(s->read_packet->family == AF_INET6);
+ s->read_packet->sender.in6 = s->peer.in6.sin6_addr;
+ s->read_packet->sender_port = be16toh(s->peer.in6.sin6_port);
+ s->read_packet->destination.in6 = s->local.in6.sin6_addr;
+ s->read_packet->destination_port = be16toh(s->local.in6.sin6_port);
+
+ if (s->read_packet->ifindex == 0)
+ s->read_packet->ifindex = s->peer.in6.sin6_scope_id;
+ if (s->read_packet->ifindex == 0)
+ s->read_packet->ifindex = s->local.in6.sin6_scope_id;
+ }
+ }
+
+ ss = read(fd,
+ (uint8_t*) DNS_PACKET_DATA(s->read_packet) + s->n_read - sizeof(s->read_size),
+ sizeof(s->read_size) + be16toh(s->read_size) - s->n_read);
+ if (ss < 0) {
+ if (errno != EINTR && errno != EAGAIN)
+ return dns_stream_complete(s, errno);
+ } else if (ss == 0)
+ return dns_stream_complete(s, ECONNRESET);
+ else
+ s->n_read += ss;
+ }
+
+ /* Are we done? If so, disable the event source for EPOLLIN */
+ if (s->n_read >= sizeof(s->read_size) + be16toh(s->read_size)) {
+ r = dns_stream_update_io(s);
+ if (r < 0)
+ return dns_stream_complete(s, -r);
+
+ /* If there's a packet handler
+ * installed, call that. Note that
+ * this is optional... */
+ if (s->on_packet)
+ return s->on_packet(s);
+ }
+ }
+ }
+
+ if ((s->write_packet && s->n_written >= sizeof(s->write_size) + s->write_packet->size) &&
+ (s->read_packet && s->n_read >= sizeof(s->read_size) + s->read_packet->size))
+ return dns_stream_complete(s, 0);
+
+ return 0;
+}
+
+DnsStream *dns_stream_unref(DnsStream *s) {
+ if (!s)
+ return NULL;
+
+ assert(s->n_ref > 0);
+ s->n_ref--;
+
+ if (s->n_ref > 0)
+ return NULL;
+
+ dns_stream_stop(s);
+
+ if (s->manager) {
+ LIST_REMOVE(streams, s->manager->dns_streams, s);
+ s->manager->n_dns_streams--;
+ }
+
+ dns_packet_unref(s->write_packet);
+ dns_packet_unref(s->read_packet);
+
+ free(s);
+
+ return NULL;
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(DnsStream*, dns_stream_unref);
+
+DnsStream *dns_stream_ref(DnsStream *s) {
+ if (!s)
+ return NULL;
+
+ assert(s->n_ref > 0);
+ s->n_ref++;
+
+ return s;
+}
+
+int dns_stream_new(Manager *m, DnsStream **ret, DnsProtocol protocol, int fd) {
+ _cleanup_(dns_stream_unrefp) DnsStream *s = NULL;
+ int r;
+
+ assert(m);
+ assert(fd >= 0);
+
+ if (m->n_dns_streams > DNS_STREAMS_MAX)
+ return -EBUSY;
+
+ s = new0(DnsStream, 1);
+ if (!s)
+ return -ENOMEM;
+
+ s->n_ref = 1;
+ s->fd = -1;
+ s->protocol = protocol;
+
+ r = sd_event_add_io(m->event, &s->io_event_source, fd, EPOLLIN, on_stream_io, s);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_source_set_description(s->io_event_source, "dns-stream-io");
+
+ r = sd_event_add_time(
+ m->event,
+ &s->timeout_event_source,
+ clock_boottime_or_monotonic(),
+ now(clock_boottime_or_monotonic()) + DNS_STREAM_TIMEOUT_USEC, 0,
+ on_stream_timeout, s);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_source_set_description(s->timeout_event_source, "dns-stream-timeout");
+
+ LIST_PREPEND(streams, m->dns_streams, s);
+ s->manager = m;
+ s->fd = fd;
+ m->n_dns_streams++;
+
+ *ret = s;
+ s = NULL;
+
+ return 0;
+}
+
+int dns_stream_write_packet(DnsStream *s, DnsPacket *p) {
+ assert(s);
+
+ if (s->write_packet)
+ return -EBUSY;
+
+ s->write_packet = dns_packet_ref(p);
+ s->write_size = htobe16(p->size);
+ s->n_written = 0;
+
+ return dns_stream_update_io(s);
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-stream.h b/src/grp-resolve/systemd-resolved/resolved-dns-stream.h
new file mode 100644
index 0000000000..bea93487de
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-stream.h
@@ -0,0 +1,80 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "basic-dns/resolved-dns-packet.h"
+#include "systemd-basic/socket-util.h"
+
+typedef struct DnsStream DnsStream;
+
+#include "resolved-dns-transaction.h"
+
+/* Streams are used by three subsystems:
+ *
+ * 1. The normal transaction logic when doing a DNS or LLMNR lookup via TCP
+ * 2. The LLMNR logic when accepting a TCP-based lookup
+ * 3. The DNS stub logic when accepting a TCP-based lookup
+ */
+
+struct DnsStream {
+ Manager *manager;
+ int n_ref;
+
+ DnsProtocol protocol;
+
+ int fd;
+ union sockaddr_union peer;
+ socklen_t peer_salen;
+ union sockaddr_union local;
+ socklen_t local_salen;
+ int ifindex;
+ uint32_t ttl;
+ bool identified;
+
+ sd_event_source *io_event_source;
+ sd_event_source *timeout_event_source;
+
+ be16_t write_size, read_size;
+ DnsPacket *write_packet, *read_packet;
+ size_t n_written, n_read;
+
+ int (*on_packet)(DnsStream *s);
+ int (*complete)(DnsStream *s, int error);
+
+ DnsTransaction *transaction; /* when used by the transaction logic */
+ DnsQuery *query; /* when used by the DNS stub logic */
+
+ LIST_FIELDS(DnsStream, streams);
+};
+
+int dns_stream_new(Manager *m, DnsStream **s, DnsProtocol protocol, int fd);
+DnsStream *dns_stream_unref(DnsStream *s);
+DnsStream *dns_stream_ref(DnsStream *s);
+
+int dns_stream_write_packet(DnsStream *s, DnsPacket *p);
+
+static inline bool DNS_STREAM_QUEUED(DnsStream *s) {
+ assert(s);
+
+ if (s->fd < 0) /* already stopped? */
+ return false;
+
+ return !!s->write_packet;
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-stub.c b/src/grp-resolve/systemd-resolved/resolved-dns-stub.c
new file mode 100644
index 0000000000..e7aa7a1c38
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-stub.c
@@ -0,0 +1,573 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2016 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "systemd-basic/fd-util.h"
+#include "systemd-basic/socket-util.h"
+
+#include "resolved-dns-stub.h"
+
+/* The MTU of the loopback device is 64K on Linux, advertise that as maximum datagram size, but subtract the Ethernet,
+ * IP and UDP header sizes */
+#define ADVERTISE_DATAGRAM_SIZE_MAX (65536U-14U-20U-8U)
+
+static int dns_stub_make_reply_packet(
+ uint16_t id,
+ int rcode,
+ DnsQuestion *q,
+ DnsAnswer *answer,
+ bool add_opt, /* add an OPT RR to this packet */
+ bool edns0_do, /* set the EDNS0 DNSSEC OK bit */
+ bool ad, /* set the DNSSEC authenticated data bit */
+ DnsPacket **ret) {
+
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ DnsResourceRecord *rr;
+ unsigned c = 0;
+ int r;
+
+ /* Note that we don't bother with any additional RRs, as this is stub is for local lookups only, and hence
+ * roundtrips aren't expensive. */
+
+ r = dns_packet_new(&p, DNS_PROTOCOL_DNS, 0);
+ if (r < 0)
+ return r;
+
+ /* If the client didn't do EDNS, clamp the rcode to 4 bit */
+ if (!add_opt && rcode > 0xF)
+ rcode = DNS_RCODE_SERVFAIL;
+
+ DNS_PACKET_HEADER(p)->id = id;
+ DNS_PACKET_HEADER(p)->flags = htobe16(DNS_PACKET_MAKE_FLAGS(
+ 1 /* qr */,
+ 0 /* opcode */,
+ 0 /* aa */,
+ 0 /* tc */,
+ 1 /* rd */,
+ 1 /* ra */,
+ ad /* ad */,
+ 0 /* cd */,
+ rcode));
+
+ r = dns_packet_append_question(p, q);
+ if (r < 0)
+ return r;
+ DNS_PACKET_HEADER(p)->qdcount = htobe16(dns_question_size(q));
+
+ DNS_ANSWER_FOREACH(rr, answer) {
+ r = dns_question_matches_rr(q, rr, NULL);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ goto add;
+
+ r = dns_question_matches_cname_or_dname(q, rr, NULL);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ goto add;
+
+ continue;
+ add:
+ r = dns_packet_append_rr(p, rr, NULL, NULL);
+ if (r < 0)
+ return r;
+
+ c++;
+ }
+ DNS_PACKET_HEADER(p)->ancount = htobe16(c);
+
+ if (add_opt) {
+ r = dns_packet_append_opt(p, ADVERTISE_DATAGRAM_SIZE_MAX, edns0_do, rcode, NULL);
+ if (r < 0)
+ return r;
+ }
+
+ *ret = p;
+ p = NULL;
+
+ return 0;
+}
+
+static void dns_stub_detach_stream(DnsStream *s) {
+ assert(s);
+
+ s->complete = NULL;
+ s->on_packet = NULL;
+ s->query = NULL;
+}
+
+static int dns_stub_send(Manager *m, DnsStream *s, DnsPacket *p, DnsPacket *reply) {
+ int r;
+
+ assert(m);
+ assert(p);
+ assert(reply);
+
+ if (s)
+ r = dns_stream_write_packet(s, reply);
+ else {
+ int fd;
+
+ /* Truncate the message to the right size */
+ if (reply->size > DNS_PACKET_PAYLOAD_SIZE_MAX(p)) {
+ dns_packet_truncate(reply, DNS_PACKET_UNICAST_SIZE_MAX);
+ DNS_PACKET_HEADER(reply)->flags = htobe16(be16toh(DNS_PACKET_HEADER(reply)->flags) | DNS_PACKET_FLAG_TC);
+ }
+
+ fd = manager_dns_stub_udp_fd(m);
+ if (fd < 0)
+ return log_debug_errno(fd, "Failed to get reply socket: %m");
+
+ /* Note that it is essential here that we explicitly choose the source IP address for this packet. This
+ * is because otherwise the kernel will choose it automatically based on the routing table and will
+ * thus pick 127.0.0.1 rather than 127.0.0.53. */
+
+ r = manager_send(m, fd, LOOPBACK_IFINDEX, p->family, &p->sender, p->sender_port, &p->destination, reply);
+ }
+ if (r < 0)
+ return log_debug_errno(r, "Failed to send reply packet: %m");
+
+ return 0;
+}
+
+static int dns_stub_send_failure(Manager *m, DnsStream *s, DnsPacket *p, int rcode) {
+ _cleanup_(dns_packet_unrefp) DnsPacket *reply = NULL;
+ int r;
+
+ assert(m);
+ assert(p);
+
+ r = dns_stub_make_reply_packet(DNS_PACKET_ID(p), rcode, p->question, NULL, !!p->opt, DNS_PACKET_DO(p), false, &reply);
+ if (r < 0)
+ return log_debug_errno(r, "Failed to build failure packet: %m");
+
+ return dns_stub_send(m, s, p, reply);
+}
+
+static void dns_stub_query_complete(DnsQuery *q) {
+ int r;
+
+ assert(q);
+ assert(q->request_dns_packet);
+
+ switch (q->state) {
+
+ case DNS_TRANSACTION_SUCCESS: {
+ _cleanup_(dns_packet_unrefp) DnsPacket *reply = NULL;
+
+ r = dns_stub_make_reply_packet(
+ DNS_PACKET_ID(q->request_dns_packet),
+ q->answer_rcode,
+ q->question_idna,
+ q->answer,
+ !!q->request_dns_packet->opt,
+ DNS_PACKET_DO(q->request_dns_packet),
+ DNS_PACKET_DO(q->request_dns_packet) && q->answer_authenticated,
+ &reply);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to build reply packet: %m");
+ break;
+ }
+
+ (void) dns_stub_send(q->manager, q->request_dns_stream, q->request_dns_packet, reply);
+ break;
+ }
+
+ case DNS_TRANSACTION_RCODE_FAILURE:
+ (void) dns_stub_send_failure(q->manager, q->request_dns_stream, q->request_dns_packet, q->answer_rcode);
+ break;
+
+ case DNS_TRANSACTION_NOT_FOUND:
+ (void) dns_stub_send_failure(q->manager, q->request_dns_stream, q->request_dns_packet, DNS_RCODE_NXDOMAIN);
+ break;
+
+ case DNS_TRANSACTION_TIMEOUT:
+ case DNS_TRANSACTION_ATTEMPTS_MAX_REACHED:
+ /* Propagate a timeout as a no packet, i.e. that the client also gets a timeout */
+ break;
+
+ case DNS_TRANSACTION_NO_SERVERS:
+ case DNS_TRANSACTION_INVALID_REPLY:
+ case DNS_TRANSACTION_ERRNO:
+ case DNS_TRANSACTION_ABORTED:
+ case DNS_TRANSACTION_DNSSEC_FAILED:
+ case DNS_TRANSACTION_NO_TRUST_ANCHOR:
+ case DNS_TRANSACTION_RR_TYPE_UNSUPPORTED:
+ case DNS_TRANSACTION_NETWORK_DOWN:
+ (void) dns_stub_send_failure(q->manager, q->request_dns_stream, q->request_dns_packet, DNS_RCODE_SERVFAIL);
+ break;
+
+ case DNS_TRANSACTION_NULL:
+ case DNS_TRANSACTION_PENDING:
+ case DNS_TRANSACTION_VALIDATING:
+ default:
+ assert_not_reached("Impossible state");
+ }
+
+ /* If there's a packet to write set, let's leave the stream around */
+ if (q->request_dns_stream && DNS_STREAM_QUEUED(q->request_dns_stream)) {
+
+ /* Detach the stream from our query (make it an orphan), but do not drop the reference to it. The
+ * default completion action of the stream will drop the reference. */
+
+ dns_stub_detach_stream(q->request_dns_stream);
+ q->request_dns_stream = NULL;
+ }
+
+ dns_query_free(q);
+}
+
+static int dns_stub_stream_complete(DnsStream *s, int error) {
+ assert(s);
+
+ log_debug_errno(error, "DNS TCP connection terminated, destroying query: %m");
+
+ assert(s->query);
+ dns_query_free(s->query);
+
+ return 0;
+}
+
+static void dns_stub_process_query(Manager *m, DnsStream *s, DnsPacket *p) {
+ DnsQuery *q = NULL;
+ int r;
+
+ assert(m);
+ assert(p);
+ assert(p->protocol == DNS_PROTOCOL_DNS);
+
+ /* Takes ownership of the *s stream object */
+
+ if (in_addr_is_localhost(p->family, &p->sender) <= 0 ||
+ in_addr_is_localhost(p->family, &p->destination) <= 0) {
+ log_error("Got packet on unexpected IP range, refusing.");
+ dns_stub_send_failure(m, s, p, DNS_RCODE_SERVFAIL);
+ goto fail;
+ }
+
+ r = dns_packet_extract(p);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to extract resources from incoming packet, ignoring packet: %m");
+ dns_stub_send_failure(m, s, p, DNS_RCODE_FORMERR);
+ goto fail;
+ }
+
+ if (!DNS_PACKET_VERSION_SUPPORTED(p)) {
+ log_debug("Got EDNS OPT field with unsupported version number.");
+ dns_stub_send_failure(m, s, p, DNS_RCODE_BADVERS);
+ goto fail;
+ }
+
+ if (dns_type_is_obsolete(p->question->keys[0]->type)) {
+ log_debug("Got message with obsolete key type, refusing.");
+ dns_stub_send_failure(m, s, p, DNS_RCODE_NOTIMP);
+ goto fail;
+ }
+
+ if (dns_type_is_zone_transer(p->question->keys[0]->type)) {
+ log_debug("Got request for zone transfer, refusing.");
+ dns_stub_send_failure(m, s, p, DNS_RCODE_NOTIMP);
+ goto fail;
+ }
+
+ if (!DNS_PACKET_RD(p)) {
+ /* If the "rd" bit is off (i.e. recursion was not requested), then refuse operation */
+ log_debug("Got request with recursion disabled, refusing.");
+ dns_stub_send_failure(m, s, p, DNS_RCODE_REFUSED);
+ goto fail;
+ }
+
+ if (DNS_PACKET_DO(p) && DNS_PACKET_CD(p)) {
+ log_debug("Got request with DNSSEC CD bit set, refusing.");
+ dns_stub_send_failure(m, s, p, DNS_RCODE_NOTIMP);
+ goto fail;
+ }
+
+ r = dns_query_new(m, &q, p->question, p->question, 0, SD_RESOLVED_PROTOCOLS_ALL|SD_RESOLVED_NO_SEARCH|SD_RESOLVED_NO_CNAME);
+ if (r < 0) {
+ log_error_errno(r, "Failed to generate query object: %m");
+ dns_stub_send_failure(m, s, p, DNS_RCODE_SERVFAIL);
+ goto fail;
+ }
+
+ /* Request that the TTL is corrected by the cached time for this lookup, so that we return vaguely useful TTLs */
+ q->clamp_ttl = true;
+
+ q->request_dns_packet = dns_packet_ref(p);
+ q->request_dns_stream = dns_stream_ref(s); /* make sure the stream stays around until we can send a reply through it */
+ q->complete = dns_stub_query_complete;
+
+ if (s) {
+ s->on_packet = NULL;
+ s->complete = dns_stub_stream_complete;
+ s->query = q;
+ }
+
+ r = dns_query_go(q);
+ if (r < 0) {
+ log_error_errno(r, "Failed to start query: %m");
+ dns_stub_send_failure(m, s, p, DNS_RCODE_SERVFAIL);
+ goto fail;
+ }
+
+ log_info("Processing query...");
+ return;
+
+fail:
+ if (s && DNS_STREAM_QUEUED(s))
+ dns_stub_detach_stream(s);
+
+ dns_query_free(q);
+}
+
+static int on_dns_stub_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ Manager *m = userdata;
+ int r;
+
+ r = manager_recv(m, fd, DNS_PROTOCOL_DNS, &p);
+ if (r <= 0)
+ return r;
+
+ if (dns_packet_validate_query(p) > 0) {
+ log_debug("Got DNS stub UDP query packet for id %u", DNS_PACKET_ID(p));
+
+ dns_stub_process_query(m, NULL, p);
+ } else
+ log_debug("Invalid DNS stub UDP packet, ignoring.");
+
+ return 0;
+}
+
+int manager_dns_stub_udp_fd(Manager *m) {
+ static const int one = 1;
+
+ union sockaddr_union sa = {
+ .in.sin_family = AF_INET,
+ .in.sin_port = htobe16(53),
+ .in.sin_addr.s_addr = htobe32(INADDR_DNS_STUB),
+ };
+
+ int r;
+
+ if (m->dns_stub_udp_fd >= 0)
+ return m->dns_stub_udp_fd;
+
+ m->dns_stub_udp_fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (m->dns_stub_udp_fd < 0)
+ return -errno;
+
+ r = setsockopt(m->dns_stub_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->dns_stub_udp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->dns_stub_udp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ /* Make sure no traffic from outside the local host can leak to onto this socket */
+ r = setsockopt(m->dns_stub_udp_fd, SOL_SOCKET, SO_BINDTODEVICE, "lo", 3);
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = bind(m->dns_stub_udp_fd, &sa.sa, sizeof(sa.in));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = sd_event_add_io(m->event, &m->dns_stub_udp_event_source, m->dns_stub_udp_fd, EPOLLIN, on_dns_stub_packet, m);
+ if (r < 0)
+ goto fail;
+
+ (void) sd_event_source_set_description(m->dns_stub_udp_event_source, "dns-stub-udp");
+
+ return m->dns_stub_udp_fd;
+
+fail:
+ m->dns_stub_udp_fd = safe_close(m->dns_stub_udp_fd);
+ return r;
+}
+
+static int on_dns_stub_stream_packet(DnsStream *s) {
+ assert(s);
+ assert(s->read_packet);
+
+ if (dns_packet_validate_query(s->read_packet) > 0) {
+ log_debug("Got DNS stub TCP query packet for id %u", DNS_PACKET_ID(s->read_packet));
+
+ dns_stub_process_query(s->manager, s, s->read_packet);
+ } else
+ log_debug("Invalid DNS stub TCP packet, ignoring.");
+
+ /* Drop the reference to the stream. Either a query was created and added its own reference to the stream now,
+ * or that didn't happen in which case we want to free the stream */
+ dns_stream_unref(s);
+
+ return 0;
+}
+
+static int on_dns_stub_stream(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ DnsStream *stream;
+ Manager *m = userdata;
+ int cfd, r;
+
+ cfd = accept4(fd, NULL, NULL, SOCK_NONBLOCK|SOCK_CLOEXEC);
+ if (cfd < 0) {
+ if (errno == EAGAIN || errno == EINTR)
+ return 0;
+
+ return -errno;
+ }
+
+ r = dns_stream_new(m, &stream, DNS_PROTOCOL_DNS, cfd);
+ if (r < 0) {
+ safe_close(cfd);
+ return r;
+ }
+
+ stream->on_packet = on_dns_stub_stream_packet;
+
+ /* We let the reference to the stream dangling here, it will either be dropped by the default "complete" action
+ * of the stream, or by our packet callback, or when the manager is shut down. */
+
+ return 0;
+}
+
+int manager_dns_stub_tcp_fd(Manager *m) {
+ static const int one = 1;
+
+ union sockaddr_union sa = {
+ .in.sin_family = AF_INET,
+ .in.sin_addr.s_addr = htobe32(INADDR_DNS_STUB),
+ .in.sin_port = htobe16(53),
+ };
+
+ int r;
+
+ if (m->dns_stub_tcp_fd >= 0)
+ return m->dns_stub_tcp_fd;
+
+ m->dns_stub_tcp_fd = socket(AF_INET, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (m->dns_stub_tcp_fd < 0)
+ return -errno;
+
+ r = setsockopt(m->dns_stub_tcp_fd, IPPROTO_IP, IP_TTL, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->dns_stub_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->dns_stub_tcp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->dns_stub_tcp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ /* Make sure no traffic from outside the local host can leak to onto this socket */
+ r = setsockopt(m->dns_stub_tcp_fd, SOL_SOCKET, SO_BINDTODEVICE, "lo", 3);
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = bind(m->dns_stub_tcp_fd, &sa.sa, sizeof(sa.in));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = listen(m->dns_stub_tcp_fd, SOMAXCONN);
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = sd_event_add_io(m->event, &m->dns_stub_tcp_event_source, m->dns_stub_tcp_fd, EPOLLIN, on_dns_stub_stream, m);
+ if (r < 0)
+ goto fail;
+
+ (void) sd_event_source_set_description(m->dns_stub_tcp_event_source, "dns-stub-tcp");
+
+ return m->dns_stub_tcp_fd;
+
+fail:
+ m->dns_stub_tcp_fd = safe_close(m->dns_stub_tcp_fd);
+ return r;
+}
+
+int manager_dns_stub_start(Manager *m) {
+ int r;
+
+ assert(m);
+
+ r = manager_dns_stub_udp_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+
+ r = manager_dns_stub_tcp_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+
+ return 0;
+
+eaddrinuse:
+ log_warning("Another process is already listening on 127.0.0.53:53. Turning off local DNS stub support.");
+ manager_dns_stub_stop(m);
+
+ return 0;
+}
+
+void manager_dns_stub_stop(Manager *m) {
+ assert(m);
+
+ m->dns_stub_udp_event_source = sd_event_source_unref(m->dns_stub_udp_event_source);
+ m->dns_stub_tcp_event_source = sd_event_source_unref(m->dns_stub_tcp_event_source);
+
+ m->dns_stub_udp_fd = safe_close(m->dns_stub_udp_fd);
+ m->dns_stub_tcp_fd = safe_close(m->dns_stub_tcp_fd);
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-stub.h b/src/grp-resolve/systemd-resolved/resolved-dns-stub.h
new file mode 100644
index 0000000000..fce4d25ede
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-stub.h
@@ -0,0 +1,31 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2016 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "resolved-manager.h"
+
+/* 127.0.0.53 in native endian */
+#define INADDR_DNS_STUB ((in_addr_t) 0x7f000035U)
+
+int manager_dns_stub_udp_fd(Manager *m);
+int manager_dns_stub_tcp_fd(Manager *m);
+
+void manager_dns_stub_stop(Manager *m);
+int manager_dns_stub_start(Manager *m);
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-synthesize.c b/src/grp-resolve/systemd-resolved/resolved-dns-synthesize.c
new file mode 100644
index 0000000000..53d1940d9e
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-synthesize.c
@@ -0,0 +1,414 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "sd-netlink/local-addresses.h"
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/hostname-util.h"
+
+#include "resolved-dns-synthesize.h"
+
+int dns_synthesize_ifindex(int ifindex) {
+
+ /* When the caller asked for resolving on a specific
+ * interface, we synthesize the answer for that
+ * interface. However, if nothing specific was claimed and we
+ * only return localhost RRs, we synthesize the answer for
+ * localhost. */
+
+ if (ifindex > 0)
+ return ifindex;
+
+ return LOOPBACK_IFINDEX;
+}
+
+int dns_synthesize_family(uint64_t flags) {
+
+ /* Picks an address family depending on set flags. This is
+ * purely for synthesized answers, where the family we return
+ * for the reply should match what was requested in the
+ * question, even though we are synthesizing the answer
+ * here. */
+
+ if (!(flags & SD_RESOLVED_DNS)) {
+ if (flags & (SD_RESOLVED_LLMNR_IPV4|SD_RESOLVED_MDNS_IPV4))
+ return AF_INET;
+ if (flags & (SD_RESOLVED_LLMNR_IPV6|SD_RESOLVED_MDNS_IPV6))
+ return AF_INET6;
+ }
+
+ return AF_UNSPEC;
+}
+
+DnsProtocol dns_synthesize_protocol(uint64_t flags) {
+
+ /* Similar as dns_synthesize_family() but does this for the
+ * protocol. If resolving via DNS was requested, we claim it
+ * was DNS. Similar, if nothing specific was
+ * requested. However, if only resolving via LLMNR was
+ * requested we return that. */
+
+ if (flags & SD_RESOLVED_DNS)
+ return DNS_PROTOCOL_DNS;
+ if (flags & SD_RESOLVED_LLMNR)
+ return DNS_PROTOCOL_LLMNR;
+ if (flags & SD_RESOLVED_MDNS)
+ return DNS_PROTOCOL_MDNS;
+
+ return DNS_PROTOCOL_DNS;
+}
+
+static int synthesize_localhost_rr(Manager *m, const DnsResourceKey *key, int ifindex, DnsAnswer **answer) {
+ int r;
+
+ assert(m);
+ assert(key);
+ assert(answer);
+
+ r = dns_answer_reserve(answer, 2);
+ if (r < 0)
+ return r;
+
+ if (IN_SET(key->type, DNS_TYPE_A, DNS_TYPE_ANY)) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+ rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_A, dns_resource_key_name(key));
+ if (!rr)
+ return -ENOMEM;
+
+ rr->a.in_addr.s_addr = htobe32(INADDR_LOOPBACK);
+
+ r = dns_answer_add(*answer, rr, dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+ }
+
+ if (IN_SET(key->type, DNS_TYPE_AAAA, DNS_TYPE_ANY)) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+ rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_AAAA, dns_resource_key_name(key));
+ if (!rr)
+ return -ENOMEM;
+
+ rr->aaaa.in6_addr = in6addr_loopback;
+
+ r = dns_answer_add(*answer, rr, dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static int answer_add_ptr(DnsAnswer **answer, const char *from, const char *to, int ifindex, DnsAnswerFlags flags) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+ rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_PTR, from);
+ if (!rr)
+ return -ENOMEM;
+
+ rr->ptr.name = strdup(to);
+ if (!rr->ptr.name)
+ return -ENOMEM;
+
+ return dns_answer_add(*answer, rr, ifindex, flags);
+}
+
+static int synthesize_localhost_ptr(Manager *m, const DnsResourceKey *key, int ifindex, DnsAnswer **answer) {
+ int r;
+
+ assert(m);
+ assert(key);
+ assert(answer);
+
+ if (IN_SET(key->type, DNS_TYPE_PTR, DNS_TYPE_ANY)) {
+ r = dns_answer_reserve(answer, 1);
+ if (r < 0)
+ return r;
+
+ r = answer_add_ptr(answer, dns_resource_key_name(key), "localhost", dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static int answer_add_addresses_rr(
+ DnsAnswer **answer,
+ const char *name,
+ struct local_address *addresses,
+ unsigned n_addresses) {
+
+ unsigned j;
+ int r;
+
+ assert(answer);
+ assert(name);
+
+ r = dns_answer_reserve(answer, n_addresses);
+ if (r < 0)
+ return r;
+
+ for (j = 0; j < n_addresses; j++) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+ r = dns_resource_record_new_address(&rr, addresses[j].family, &addresses[j].address, name);
+ if (r < 0)
+ return r;
+
+ r = dns_answer_add(*answer, rr, addresses[j].ifindex, DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static int answer_add_addresses_ptr(
+ DnsAnswer **answer,
+ const char *name,
+ struct local_address *addresses,
+ unsigned n_addresses,
+ int af, const union in_addr_union *match) {
+
+ unsigned j;
+ int r;
+
+ assert(answer);
+ assert(name);
+
+ for (j = 0; j < n_addresses; j++) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+ if (af != AF_UNSPEC) {
+
+ if (addresses[j].family != af)
+ continue;
+
+ if (match && !in_addr_equal(af, match, &addresses[j].address))
+ continue;
+ }
+
+ r = dns_answer_reserve(answer, 1);
+ if (r < 0)
+ return r;
+
+ r = dns_resource_record_new_reverse(&rr, addresses[j].family, &addresses[j].address, name);
+ if (r < 0)
+ return r;
+
+ r = dns_answer_add(*answer, rr, addresses[j].ifindex, DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static int synthesize_system_hostname_rr(Manager *m, const DnsResourceKey *key, int ifindex, DnsAnswer **answer) {
+ _cleanup_free_ struct local_address *addresses = NULL;
+ int n = 0, af;
+
+ assert(m);
+ assert(key);
+ assert(answer);
+
+ af = dns_type_to_af(key->type);
+ if (af >= 0) {
+ n = local_addresses(m->rtnl, ifindex, af, &addresses);
+ if (n < 0)
+ return n;
+
+ if (n == 0) {
+ struct local_address buffer[2];
+
+ /* If we have no local addresses then use ::1
+ * and 127.0.0.2 as local ones. */
+
+ if (af == AF_INET || af == AF_UNSPEC)
+ buffer[n++] = (struct local_address) {
+ .family = AF_INET,
+ .ifindex = dns_synthesize_ifindex(ifindex),
+ .address.in.s_addr = htobe32(0x7F000002),
+ };
+
+ if (af == AF_INET6 || af == AF_UNSPEC)
+ buffer[n++] = (struct local_address) {
+ .family = AF_INET6,
+ .ifindex = dns_synthesize_ifindex(ifindex),
+ .address.in6 = in6addr_loopback,
+ };
+
+ return answer_add_addresses_rr(answer, dns_resource_key_name(key), buffer, n);
+ }
+ }
+
+ return answer_add_addresses_rr(answer, dns_resource_key_name(key), addresses, n);
+}
+
+static int synthesize_system_hostname_ptr(Manager *m, int af, const union in_addr_union *address, int ifindex, DnsAnswer **answer) {
+ _cleanup_free_ struct local_address *addresses = NULL;
+ int n, r;
+
+ assert(m);
+ assert(address);
+ assert(answer);
+
+ if (af == AF_INET && address->in.s_addr == htobe32(0x7F000002)) {
+
+ /* Always map the IPv4 address 127.0.0.2 to the local
+ * hostname, in addition to "localhost": */
+
+ r = dns_answer_reserve(answer, 3);
+ if (r < 0)
+ return r;
+
+ r = answer_add_ptr(answer, "2.0.0.127.in-addr.arpa", m->llmnr_hostname, dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+
+ r = answer_add_ptr(answer, "2.0.0.127.in-addr.arpa", m->mdns_hostname, dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+
+ r = answer_add_ptr(answer, "2.0.0.127.in-addr.arpa", "localhost", dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+
+ return 0;
+ }
+
+ n = local_addresses(m->rtnl, ifindex, af, &addresses);
+ if (n < 0)
+ return n;
+
+ r = answer_add_addresses_ptr(answer, m->llmnr_hostname, addresses, n, af, address);
+ if (r < 0)
+ return r;
+
+ return answer_add_addresses_ptr(answer, m->mdns_hostname, addresses, n, af, address);
+}
+
+static int synthesize_gateway_rr(Manager *m, const DnsResourceKey *key, int ifindex, DnsAnswer **answer) {
+ _cleanup_free_ struct local_address *addresses = NULL;
+ int n = 0, af;
+
+ assert(m);
+ assert(key);
+ assert(answer);
+
+ af = dns_type_to_af(key->type);
+ if (af >= 0) {
+ n = local_gateways(m->rtnl, ifindex, af, &addresses);
+ if (n < 0)
+ return n;
+ }
+
+ return answer_add_addresses_rr(answer, dns_resource_key_name(key), addresses, n);
+}
+
+static int synthesize_gateway_ptr(Manager *m, int af, const union in_addr_union *address, int ifindex, DnsAnswer **answer) {
+ _cleanup_free_ struct local_address *addresses = NULL;
+ int n;
+
+ assert(m);
+ assert(address);
+ assert(answer);
+
+ n = local_gateways(m->rtnl, ifindex, af, &addresses);
+ if (n < 0)
+ return n;
+
+ return answer_add_addresses_ptr(answer, "gateway", addresses, n, af, address);
+}
+
+int dns_synthesize_answer(
+ Manager *m,
+ DnsQuestion *q,
+ int ifindex,
+ DnsAnswer **ret) {
+
+ _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
+ DnsResourceKey *key;
+ bool found = false;
+ int r;
+
+ assert(m);
+ assert(q);
+
+ DNS_QUESTION_FOREACH(key, q) {
+ union in_addr_union address;
+ const char *name;
+ int af;
+
+ if (key->class != DNS_CLASS_IN &&
+ key->class != DNS_CLASS_ANY)
+ continue;
+
+ name = dns_resource_key_name(key);
+
+ if (is_localhost(name)) {
+
+ r = synthesize_localhost_rr(m, key, ifindex, &answer);
+ if (r < 0)
+ return log_error_errno(r, "Failed to synthesize localhost RRs: %m");
+
+ } else if (manager_is_own_hostname(m, name)) {
+
+ r = synthesize_system_hostname_rr(m, key, ifindex, &answer);
+ if (r < 0)
+ return log_error_errno(r, "Failed to synthesize system hostname RRs: %m");
+
+ } else if (is_gateway_hostname(name)) {
+
+ r = synthesize_gateway_rr(m, key, ifindex, &answer);
+ if (r < 0)
+ return log_error_errno(r, "Failed to synthesize gateway RRs: %m");
+
+ } else if ((dns_name_endswith(name, "127.in-addr.arpa") > 0 && dns_name_equal(name, "2.0.0.127.in-addr.arpa") == 0) ||
+ dns_name_equal(name, "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa") > 0) {
+
+ r = synthesize_localhost_ptr(m, key, ifindex, &answer);
+ if (r < 0)
+ return log_error_errno(r, "Failed to synthesize localhost PTR RRs: %m");
+
+ } else if (dns_name_address(name, &af, &address) > 0) {
+
+ r = synthesize_system_hostname_ptr(m, af, &address, ifindex, &answer);
+ if (r < 0)
+ return log_error_errno(r, "Failed to synthesize system hostname PTR RR: %m");
+
+ r = synthesize_gateway_ptr(m, af, &address, ifindex, &answer);
+ if (r < 0)
+ return log_error_errno(r, "Failed to synthesize gateway hostname PTR RR: %m");
+ } else
+ continue;
+
+ found = true;
+ }
+
+ r = found;
+
+ if (ret) {
+ *ret = answer;
+ answer = NULL;
+ }
+
+ return r;
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-synthesize.h b/src/grp-resolve/systemd-resolved/resolved-dns-synthesize.h
new file mode 100644
index 0000000000..23b05587ac
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-synthesize.h
@@ -0,0 +1,31 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2016 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "basic-dns/resolved-dns-answer.h"
+#include "basic-dns/resolved-dns-question.h"
+
+#include "resolved-manager.h"
+
+int dns_synthesize_ifindex(int ifindex);
+int dns_synthesize_family(uint64_t flags);
+DnsProtocol dns_synthesize_protocol(uint64_t flags);
+
+int dns_synthesize_answer(Manager *m, DnsQuestion *q, int ifindex, DnsAnswer **ret);
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-transaction.c b/src/grp-resolve/systemd-resolved/resolved-dns-transaction.c
new file mode 100644
index 0000000000..a5ae8d0853
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-transaction.c
@@ -0,0 +1,3108 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <systemd/sd-messages.h>
+
+#include "systemd-basic/af-list.h"
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/errno-list.h"
+#include "systemd-basic/fd-util.h"
+#include "systemd-basic/random-util.h"
+#include "systemd-basic/string-table.h"
+#include "systemd-shared/dns-domain.h"
+
+#include "resolved-dns-cache.h"
+#include "resolved-dns-transaction.h"
+#include "resolved-llmnr.h"
+
+#define TRANSACTIONS_MAX 4096
+
+static void dns_transaction_reset_answer(DnsTransaction *t) {
+ assert(t);
+
+ t->received = dns_packet_unref(t->received);
+ t->answer = dns_answer_unref(t->answer);
+ t->answer_rcode = 0;
+ t->answer_dnssec_result = _DNSSEC_RESULT_INVALID;
+ t->answer_source = _DNS_TRANSACTION_SOURCE_INVALID;
+ t->answer_authenticated = false;
+ t->answer_nsec_ttl = (uint32_t) -1;
+ t->answer_errno = 0;
+}
+
+static void dns_transaction_flush_dnssec_transactions(DnsTransaction *t) {
+ DnsTransaction *z;
+
+ assert(t);
+
+ while ((z = set_steal_first(t->dnssec_transactions))) {
+ set_remove(z->notify_transactions, t);
+ set_remove(z->notify_transactions_done, t);
+ dns_transaction_gc(z);
+ }
+}
+
+static void dns_transaction_close_connection(DnsTransaction *t) {
+ assert(t);
+
+ if (t->stream) {
+ /* Let's detach the stream from our transaction, in case something else keeps a reference to it. */
+ t->stream->complete = NULL;
+ t->stream->on_packet = NULL;
+ t->stream->transaction = NULL;
+ t->stream = dns_stream_unref(t->stream);
+ }
+
+ t->dns_udp_event_source = sd_event_source_unref(t->dns_udp_event_source);
+ t->dns_udp_fd = safe_close(t->dns_udp_fd);
+}
+
+static void dns_transaction_stop_timeout(DnsTransaction *t) {
+ assert(t);
+
+ t->timeout_event_source = sd_event_source_unref(t->timeout_event_source);
+}
+
+DnsTransaction* dns_transaction_free(DnsTransaction *t) {
+ DnsQueryCandidate *c;
+ DnsZoneItem *i;
+ DnsTransaction *z;
+
+ if (!t)
+ return NULL;
+
+ log_debug("Freeing transaction %" PRIu16 ".", t->id);
+
+ dns_transaction_close_connection(t);
+ dns_transaction_stop_timeout(t);
+
+ dns_packet_unref(t->sent);
+ dns_transaction_reset_answer(t);
+
+ dns_server_unref(t->server);
+
+ if (t->scope) {
+ hashmap_remove_value(t->scope->transactions_by_key, t->key, t);
+ LIST_REMOVE(transactions_by_scope, t->scope->transactions, t);
+
+ if (t->id != 0)
+ hashmap_remove(t->scope->manager->dns_transactions, UINT_TO_PTR(t->id));
+ }
+
+ while ((c = set_steal_first(t->notify_query_candidates)))
+ set_remove(c->transactions, t);
+ set_free(t->notify_query_candidates);
+
+ while ((c = set_steal_first(t->notify_query_candidates_done)))
+ set_remove(c->transactions, t);
+ set_free(t->notify_query_candidates_done);
+
+ while ((i = set_steal_first(t->notify_zone_items)))
+ i->probe_transaction = NULL;
+ set_free(t->notify_zone_items);
+
+ while ((i = set_steal_first(t->notify_zone_items_done)))
+ i->probe_transaction = NULL;
+ set_free(t->notify_zone_items_done);
+
+ while ((z = set_steal_first(t->notify_transactions)))
+ set_remove(z->dnssec_transactions, t);
+ set_free(t->notify_transactions);
+
+ while ((z = set_steal_first(t->notify_transactions_done)))
+ set_remove(z->dnssec_transactions, t);
+ set_free(t->notify_transactions_done);
+
+ dns_transaction_flush_dnssec_transactions(t);
+ set_free(t->dnssec_transactions);
+
+ dns_answer_unref(t->validated_keys);
+ dns_resource_key_unref(t->key);
+
+ free(t);
+ return NULL;
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(DnsTransaction*, dns_transaction_free);
+
+bool dns_transaction_gc(DnsTransaction *t) {
+ assert(t);
+
+ if (t->block_gc > 0)
+ return true;
+
+ if (set_isempty(t->notify_query_candidates) &&
+ set_isempty(t->notify_query_candidates_done) &&
+ set_isempty(t->notify_zone_items) &&
+ set_isempty(t->notify_zone_items_done) &&
+ set_isempty(t->notify_transactions) &&
+ set_isempty(t->notify_transactions_done)) {
+ dns_transaction_free(t);
+ return false;
+ }
+
+ return true;
+}
+
+static uint16_t pick_new_id(Manager *m) {
+ uint16_t new_id;
+
+ /* Find a fresh, unused transaction id. Note that this loop is bounded because there's a limit on the number of
+ * transactions, and it's much lower than the space of IDs. */
+
+ assert_cc(TRANSACTIONS_MAX < 0xFFFF);
+
+ do
+ random_bytes(&new_id, sizeof(new_id));
+ while (new_id == 0 ||
+ hashmap_get(m->dns_transactions, UINT_TO_PTR(new_id)));
+
+ return new_id;
+}
+
+int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsResourceKey *key) {
+ _cleanup_(dns_transaction_freep) DnsTransaction *t = NULL;
+ int r;
+
+ assert(ret);
+ assert(s);
+ assert(key);
+
+ /* Don't allow looking up invalid or pseudo RRs */
+ if (!dns_type_is_valid_query(key->type))
+ return -EINVAL;
+ if (dns_type_is_obsolete(key->type))
+ return -EOPNOTSUPP;
+
+ /* We only support the IN class */
+ if (key->class != DNS_CLASS_IN && key->class != DNS_CLASS_ANY)
+ return -EOPNOTSUPP;
+
+ if (hashmap_size(s->manager->dns_transactions) >= TRANSACTIONS_MAX)
+ return -EBUSY;
+
+ r = hashmap_ensure_allocated(&s->manager->dns_transactions, NULL);
+ if (r < 0)
+ return r;
+
+ r = hashmap_ensure_allocated(&s->transactions_by_key, &dns_resource_key_hash_ops);
+ if (r < 0)
+ return r;
+
+ t = new0(DnsTransaction, 1);
+ if (!t)
+ return -ENOMEM;
+
+ t->dns_udp_fd = -1;
+ t->answer_source = _DNS_TRANSACTION_SOURCE_INVALID;
+ t->answer_dnssec_result = _DNSSEC_RESULT_INVALID;
+ t->answer_nsec_ttl = (uint32_t) -1;
+ t->key = dns_resource_key_ref(key);
+ t->current_feature_level = _DNS_SERVER_FEATURE_LEVEL_INVALID;
+ t->clamp_feature_level = _DNS_SERVER_FEATURE_LEVEL_INVALID;
+
+ t->id = pick_new_id(s->manager);
+
+ r = hashmap_put(s->manager->dns_transactions, UINT_TO_PTR(t->id), t);
+ if (r < 0) {
+ t->id = 0;
+ return r;
+ }
+
+ r = hashmap_replace(s->transactions_by_key, t->key, t);
+ if (r < 0) {
+ hashmap_remove(s->manager->dns_transactions, UINT_TO_PTR(t->id));
+ return r;
+ }
+
+ LIST_PREPEND(transactions_by_scope, s->transactions, t);
+ t->scope = s;
+
+ s->manager->n_transactions_total++;
+
+ if (ret)
+ *ret = t;
+
+ t = NULL;
+
+ return 0;
+}
+
+static void dns_transaction_shuffle_id(DnsTransaction *t) {
+ uint16_t new_id;
+ assert(t);
+
+ /* Pick a new ID for this transaction. */
+
+ new_id = pick_new_id(t->scope->manager);
+ assert_se(hashmap_remove_and_put(t->scope->manager->dns_transactions, UINT_TO_PTR(t->id), UINT_TO_PTR(new_id), t) >= 0);
+
+ log_debug("Transaction %" PRIu16 " is now %" PRIu16 ".", t->id, new_id);
+ t->id = new_id;
+
+ /* Make sure we generate a new packet with the new ID */
+ t->sent = dns_packet_unref(t->sent);
+}
+
+static void dns_transaction_tentative(DnsTransaction *t, DnsPacket *p) {
+ _cleanup_free_ char *pretty = NULL;
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
+ DnsZoneItem *z;
+
+ assert(t);
+ assert(p);
+
+ if (manager_our_packet(t->scope->manager, p) != 0)
+ return;
+
+ (void) in_addr_to_string(p->family, &p->sender, &pretty);
+
+ log_debug("Transaction %" PRIu16 " for <%s> on scope %s on %s/%s got tentative packet from %s.",
+ t->id,
+ dns_resource_key_to_string(t->key, key_str, sizeof key_str),
+ dns_protocol_to_string(t->scope->protocol),
+ t->scope->link ? t->scope->link->name : "*",
+ af_to_name_short(t->scope->family),
+ strnull(pretty));
+
+ /* RFC 4795, Section 4.1 says that the peer with the
+ * lexicographically smaller IP address loses */
+ if (memcmp(&p->sender, &p->destination, FAMILY_ADDRESS_SIZE(p->family)) >= 0) {
+ log_debug("Peer has lexicographically larger IP address and thus lost in the conflict.");
+ return;
+ }
+
+ log_debug("We have the lexicographically larger IP address and thus lost in the conflict.");
+
+ t->block_gc++;
+
+ while ((z = set_first(t->notify_zone_items))) {
+ /* First, make sure the zone item drops the reference
+ * to us */
+ dns_zone_item_probe_stop(z);
+
+ /* Secondly, report this as conflict, so that we might
+ * look for a different hostname */
+ dns_zone_item_conflict(z);
+ }
+ t->block_gc--;
+
+ dns_transaction_gc(t);
+}
+
+void dns_transaction_complete(DnsTransaction *t, DnsTransactionState state) {
+ DnsQueryCandidate *c;
+ DnsZoneItem *z;
+ DnsTransaction *d;
+ const char *st;
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
+
+ assert(t);
+ assert(!DNS_TRANSACTION_IS_LIVE(state));
+
+ if (state == DNS_TRANSACTION_DNSSEC_FAILED) {
+ dns_resource_key_to_string(t->key, key_str, sizeof key_str);
+
+ log_struct(LOG_NOTICE,
+ LOG_MESSAGE_ID(SD_MESSAGE_DNSSEC_FAILURE),
+ LOG_MESSAGE("DNSSEC validation failed for question %s: %s", key_str, dnssec_result_to_string(t->answer_dnssec_result)),
+ "DNS_TRANSACTION=%" PRIu16, t->id,
+ "DNS_QUESTION=%s", key_str,
+ "DNSSEC_RESULT=%s", dnssec_result_to_string(t->answer_dnssec_result),
+ "DNS_SERVER=%s", dns_server_string(t->server),
+ "DNS_SERVER_FEATURE_LEVEL=%s", dns_server_feature_level_to_string(t->server->possible_feature_level),
+ NULL);
+ }
+
+ /* Note that this call might invalidate the query. Callers
+ * should hence not attempt to access the query or transaction
+ * after calling this function. */
+
+ if (state == DNS_TRANSACTION_ERRNO)
+ st = errno_to_name(t->answer_errno);
+ else
+ st = dns_transaction_state_to_string(state);
+
+ log_debug("Transaction %" PRIu16 " for <%s> on scope %s on %s/%s now complete with <%s> from %s (%s).",
+ t->id,
+ dns_resource_key_to_string(t->key, key_str, sizeof key_str),
+ dns_protocol_to_string(t->scope->protocol),
+ t->scope->link ? t->scope->link->name : "*",
+ af_to_name_short(t->scope->family),
+ st,
+ t->answer_source < 0 ? "none" : dns_transaction_source_to_string(t->answer_source),
+ t->answer_authenticated ? "authenticated" : "unsigned");
+
+ t->state = state;
+
+ dns_transaction_close_connection(t);
+ dns_transaction_stop_timeout(t);
+
+ /* Notify all queries that are interested, but make sure the
+ * transaction isn't freed while we are still looking at it */
+ t->block_gc++;
+
+ SET_FOREACH_MOVE(c, t->notify_query_candidates_done, t->notify_query_candidates)
+ dns_query_candidate_notify(c);
+ SWAP_TWO(t->notify_query_candidates, t->notify_query_candidates_done);
+
+ SET_FOREACH_MOVE(z, t->notify_zone_items_done, t->notify_zone_items)
+ dns_zone_item_notify(z);
+ SWAP_TWO(t->notify_zone_items, t->notify_zone_items_done);
+
+ SET_FOREACH_MOVE(d, t->notify_transactions_done, t->notify_transactions)
+ dns_transaction_notify(d, t);
+ SWAP_TWO(t->notify_transactions, t->notify_transactions_done);
+
+ t->block_gc--;
+ dns_transaction_gc(t);
+}
+
+static int dns_transaction_pick_server(DnsTransaction *t) {
+ DnsServer *server;
+
+ assert(t);
+ assert(t->scope->protocol == DNS_PROTOCOL_DNS);
+
+ /* Pick a DNS server and a feature level for it. */
+
+ server = dns_scope_get_dns_server(t->scope);
+ if (!server)
+ return -ESRCH;
+
+ /* If we changed the server invalidate the feature level clamping, as the new server might have completely
+ * different properties. */
+ if (server != t->server)
+ t->clamp_feature_level = _DNS_SERVER_FEATURE_LEVEL_INVALID;
+
+ t->current_feature_level = dns_server_possible_feature_level(server);
+
+ /* Clamp the feature level if that is requested. */
+ if (t->clamp_feature_level != _DNS_SERVER_FEATURE_LEVEL_INVALID &&
+ t->current_feature_level > t->clamp_feature_level)
+ t->current_feature_level = t->clamp_feature_level;
+
+ log_debug("Using feature level %s for transaction %u.", dns_server_feature_level_to_string(t->current_feature_level), t->id);
+
+ if (server == t->server)
+ return 0;
+
+ dns_server_unref(t->server);
+ t->server = dns_server_ref(server);
+
+ log_debug("Using DNS server %s for transaction %u.", dns_server_string(t->server), t->id);
+
+ return 1;
+}
+
+static void dns_transaction_retry(DnsTransaction *t, bool next_server) {
+ int r;
+
+ assert(t);
+
+ log_debug("Retrying transaction %" PRIu16 ".", t->id);
+
+ /* Before we try again, switch to a new server. */
+ if (next_server)
+ dns_scope_next_dns_server(t->scope);
+
+ r = dns_transaction_go(t);
+ if (r < 0) {
+ t->answer_errno = -r;
+ dns_transaction_complete(t, DNS_TRANSACTION_ERRNO);
+ }
+}
+
+static int dns_transaction_maybe_restart(DnsTransaction *t) {
+ int r;
+
+ assert(t);
+
+ /* Returns > 0 if the transaction was restarted, 0 if not */
+
+ if (!t->server)
+ return 0;
+
+ if (t->current_feature_level <= dns_server_possible_feature_level(t->server))
+ return 0;
+
+ /* The server's current feature level is lower than when we sent the original query. We learnt something from
+ the response or possibly an auxiliary DNSSEC response that we didn't know before. We take that as reason to
+ restart the whole transaction. This is a good idea to deal with servers that respond rubbish if we include
+ OPT RR or DO bit. One of these cases is documented here, for example:
+ https://open.nlnetlabs.nl/pipermail/dnssec-trigger/2014-November/000376.html */
+
+ log_debug("Server feature level is now lower than when we began our transaction. Restarting with new ID.");
+ dns_transaction_shuffle_id(t);
+
+ r = dns_transaction_go(t);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+static int on_stream_complete(DnsStream *s, int error) {
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ DnsTransaction *t;
+
+ assert(s);
+ assert(s->transaction);
+
+ /* Copy the data we care about out of the stream before we
+ * destroy it. */
+ t = s->transaction;
+ p = dns_packet_ref(s->read_packet);
+
+ dns_transaction_close_connection(t);
+
+ if (ERRNO_IS_DISCONNECT(error)) {
+ usec_t usec;
+
+ if (t->scope->protocol == DNS_PROTOCOL_LLMNR) {
+ /* If the LLMNR/TCP connection failed, the host doesn't support LLMNR, and we cannot answer the
+ * question on this scope. */
+ dns_transaction_complete(t, DNS_TRANSACTION_NOT_FOUND);
+ return 0;
+ }
+
+ log_debug_errno(error, "Connection failure for DNS TCP stream: %m");
+ assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &usec) >= 0);
+ dns_server_packet_lost(t->server, IPPROTO_TCP, t->current_feature_level, usec - t->start_usec);
+
+ dns_transaction_retry(t, true);
+ return 0;
+ }
+ if (error != 0) {
+ t->answer_errno = error;
+ dns_transaction_complete(t, DNS_TRANSACTION_ERRNO);
+ return 0;
+ }
+
+ if (dns_packet_validate_reply(p) <= 0) {
+ log_debug("Invalid TCP reply packet.");
+ dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
+ return 0;
+ }
+
+ dns_scope_check_conflicts(t->scope, p);
+
+ t->block_gc++;
+ dns_transaction_process_reply(t, p);
+ t->block_gc--;
+
+ /* If the response wasn't useful, then complete the transition
+ * now. After all, we are the worst feature set now with TCP
+ * sockets, and there's really no point in retrying. */
+ if (t->state == DNS_TRANSACTION_PENDING)
+ dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
+ else
+ dns_transaction_gc(t);
+
+ return 0;
+}
+
+static int dns_transaction_open_tcp(DnsTransaction *t) {
+ _cleanup_close_ int fd = -1;
+ int r;
+
+ assert(t);
+
+ dns_transaction_close_connection(t);
+
+ switch (t->scope->protocol) {
+
+ case DNS_PROTOCOL_DNS:
+ r = dns_transaction_pick_server(t);
+ if (r < 0)
+ return r;
+
+ if (!dns_server_dnssec_supported(t->server) && dns_type_is_dnssec(t->key->type))
+ return -EOPNOTSUPP;
+
+ r = dns_server_adjust_opt(t->server, t->sent, t->current_feature_level);
+ if (r < 0)
+ return r;
+
+ fd = dns_scope_socket_tcp(t->scope, AF_UNSPEC, NULL, t->server, 53);
+ break;
+
+ case DNS_PROTOCOL_LLMNR:
+ /* When we already received a reply to this (but it was truncated), send to its sender address */
+ if (t->received)
+ fd = dns_scope_socket_tcp(t->scope, t->received->family, &t->received->sender, NULL, t->received->sender_port);
+ else {
+ union in_addr_union address;
+ int family = AF_UNSPEC;
+
+ /* Otherwise, try to talk to the owner of a
+ * the IP address, in case this is a reverse
+ * PTR lookup */
+
+ r = dns_name_address(dns_resource_key_name(t->key), &family, &address);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EINVAL;
+ if (family != t->scope->family)
+ return -ESRCH;
+
+ fd = dns_scope_socket_tcp(t->scope, family, &address, NULL, LLMNR_PORT);
+ }
+
+ break;
+
+ default:
+ return -EAFNOSUPPORT;
+ }
+
+ if (fd < 0)
+ return fd;
+
+ r = dns_stream_new(t->scope->manager, &t->stream, t->scope->protocol, fd);
+ if (r < 0)
+ return r;
+ fd = -1;
+
+ r = dns_stream_write_packet(t->stream, t->sent);
+ if (r < 0) {
+ t->stream = dns_stream_unref(t->stream);
+ return r;
+ }
+
+ t->stream->complete = on_stream_complete;
+ t->stream->transaction = t;
+
+ /* The interface index is difficult to determine if we are
+ * connecting to the local host, hence fill this in right away
+ * instead of determining it from the socket */
+ t->stream->ifindex = dns_scope_ifindex(t->scope);
+
+ dns_transaction_reset_answer(t);
+
+ t->tried_stream = true;
+
+ return 0;
+}
+
+static void dns_transaction_cache_answer(DnsTransaction *t) {
+ assert(t);
+
+ /* For mDNS we cache whenever we get the packet, rather than
+ * in each transaction. */
+ if (!IN_SET(t->scope->protocol, DNS_PROTOCOL_DNS, DNS_PROTOCOL_LLMNR))
+ return;
+
+ /* Caching disabled? */
+ if (!t->scope->manager->enable_cache)
+ return;
+
+ /* We never cache if this packet is from the local host, under
+ * the assumption that a locally running DNS server would
+ * cache this anyway, and probably knows better when to flush
+ * the cache then we could. */
+ if (!DNS_PACKET_SHALL_CACHE(t->received))
+ return;
+
+ dns_cache_put(&t->scope->cache,
+ t->key,
+ t->answer_rcode,
+ t->answer,
+ t->answer_authenticated,
+ t->answer_nsec_ttl,
+ 0,
+ t->received->family,
+ &t->received->sender);
+}
+
+static bool dns_transaction_dnssec_is_live(DnsTransaction *t) {
+ DnsTransaction *dt;
+ Iterator i;
+
+ assert(t);
+
+ SET_FOREACH(dt, t->dnssec_transactions, i)
+ if (DNS_TRANSACTION_IS_LIVE(dt->state))
+ return true;
+
+ return false;
+}
+
+static int dns_transaction_dnssec_ready(DnsTransaction *t) {
+ DnsTransaction *dt;
+ Iterator i;
+
+ assert(t);
+
+ /* Checks whether the auxiliary DNSSEC transactions of our transaction have completed, or are still
+ * ongoing. Returns 0, if we aren't ready for the DNSSEC validation, positive if we are. */
+
+ SET_FOREACH(dt, t->dnssec_transactions, i) {
+
+ switch (dt->state) {
+
+ case DNS_TRANSACTION_NULL:
+ case DNS_TRANSACTION_PENDING:
+ case DNS_TRANSACTION_VALIDATING:
+ /* Still ongoing */
+ return 0;
+
+ case DNS_TRANSACTION_RCODE_FAILURE:
+ if (!IN_SET(dt->answer_rcode, DNS_RCODE_NXDOMAIN, DNS_RCODE_SERVFAIL)) {
+ log_debug("Auxiliary DNSSEC RR query failed with rcode=%s.", dns_rcode_to_string(dt->answer_rcode));
+ goto fail;
+ }
+
+ /* Fall-through: NXDOMAIN/SERVFAIL is good enough for us. This is because some DNS servers
+ * erronously return NXDOMAIN/SERVFAIL for empty non-terminals (Akamai...) or missing DS
+ * records (Facebook), and we need to handle that nicely, when asking for parent SOA or similar
+ * RRs to make unsigned proofs. */
+
+ case DNS_TRANSACTION_SUCCESS:
+ /* All good. */
+ break;
+
+ case DNS_TRANSACTION_DNSSEC_FAILED:
+ /* We handle DNSSEC failures different from other errors, as we care about the DNSSEC
+ * validationr result */
+
+ log_debug("Auxiliary DNSSEC RR query failed validation: %s", dnssec_result_to_string(dt->answer_dnssec_result));
+ t->answer_dnssec_result = dt->answer_dnssec_result; /* Copy error code over */
+ dns_transaction_complete(t, DNS_TRANSACTION_DNSSEC_FAILED);
+ return 0;
+
+
+ default:
+ log_debug("Auxiliary DNSSEC RR query failed with %s", dns_transaction_state_to_string(dt->state));
+ goto fail;
+ }
+ }
+
+ /* All is ready, we can go and validate */
+ return 1;
+
+fail:
+ t->answer_dnssec_result = DNSSEC_FAILED_AUXILIARY;
+ dns_transaction_complete(t, DNS_TRANSACTION_DNSSEC_FAILED);
+ return 0;
+}
+
+static void dns_transaction_process_dnssec(DnsTransaction *t) {
+ int r;
+
+ assert(t);
+
+ /* Are there ongoing DNSSEC transactions? If so, let's wait for them. */
+ r = dns_transaction_dnssec_ready(t);
+ if (r < 0)
+ goto fail;
+ if (r == 0) /* We aren't ready yet (or one of our auxiliary transactions failed, and we shouldn't validate now */
+ return;
+
+ /* See if we learnt things from the additional DNSSEC transactions, that we didn't know before, and better
+ * restart the lookup immediately. */
+ r = dns_transaction_maybe_restart(t);
+ if (r < 0)
+ goto fail;
+ if (r > 0) /* Transaction got restarted... */
+ return;
+
+ /* All our auxiliary DNSSEC transactions are complete now. Try
+ * to validate our RRset now. */
+ r = dns_transaction_validate_dnssec(t);
+ if (r == -EBADMSG) {
+ dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
+ return;
+ }
+ if (r < 0)
+ goto fail;
+
+ if (t->answer_dnssec_result == DNSSEC_INCOMPATIBLE_SERVER &&
+ t->scope->dnssec_mode == DNSSEC_YES) {
+ /* We are not in automatic downgrade mode, and the
+ * server is bad, refuse operation. */
+ dns_transaction_complete(t, DNS_TRANSACTION_DNSSEC_FAILED);
+ return;
+ }
+
+ if (!IN_SET(t->answer_dnssec_result,
+ _DNSSEC_RESULT_INVALID, /* No DNSSEC validation enabled */
+ DNSSEC_VALIDATED, /* Answer is signed and validated successfully */
+ DNSSEC_UNSIGNED, /* Answer is right-fully unsigned */
+ DNSSEC_INCOMPATIBLE_SERVER)) { /* Server does not do DNSSEC (Yay, we are downgrade attack vulnerable!) */
+ dns_transaction_complete(t, DNS_TRANSACTION_DNSSEC_FAILED);
+ return;
+ }
+
+ if (t->answer_dnssec_result == DNSSEC_INCOMPATIBLE_SERVER)
+ dns_server_warn_downgrade(t->server);
+
+ dns_transaction_cache_answer(t);
+
+ if (t->answer_rcode == DNS_RCODE_SUCCESS)
+ dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);
+ else
+ dns_transaction_complete(t, DNS_TRANSACTION_RCODE_FAILURE);
+
+ return;
+
+fail:
+ t->answer_errno = -r;
+ dns_transaction_complete(t, DNS_TRANSACTION_ERRNO);
+}
+
+static int dns_transaction_has_positive_answer(DnsTransaction *t, DnsAnswerFlags *flags) {
+ int r;
+
+ assert(t);
+
+ /* Checks whether the answer is positive, i.e. either a direct
+ * answer to the question, or a CNAME/DNAME for it */
+
+ r = dns_answer_match_key(t->answer, t->key, flags);
+ if (r != 0)
+ return r;
+
+ r = dns_answer_find_cname_or_dname(t->answer, t->key, NULL, flags);
+ if (r != 0)
+ return r;
+
+ return false;
+}
+
+static int dns_transaction_fix_rcode(DnsTransaction *t) {
+ int r;
+
+ assert(t);
+
+ /* Fix up the RCODE to SUCCESS if we get at least one matching RR in a response. Note that this contradicts the
+ * DNS RFCs a bit. Specifically, RFC 6604 Section 3 clarifies that the RCODE shall say something about a
+ * CNAME/DNAME chain element coming after the last chain element contained in the message, and not the first
+ * one included. However, it also indicates that not all DNS servers implement this correctly. Moreover, when
+ * using DNSSEC we usually only can prove the first element of a CNAME/DNAME chain anyway, hence let's settle
+ * on always processing the RCODE as referring to the immediate look-up we do, i.e. the first element of a
+ * CNAME/DNAME chain. This way, we uniformly handle CNAME/DNAME chains, regardless if the DNS server
+ * incorrectly implements RCODE, whether DNSSEC is in use, or whether the DNS server only supplied us with an
+ * incomplete CNAME/DNAME chain.
+ *
+ * Or in other words: if we get at least one positive reply in a message we patch NXDOMAIN to become SUCCESS,
+ * and then rely on the CNAME chasing logic to figure out that there's actually a CNAME error with a new
+ * lookup. */
+
+ if (t->answer_rcode != DNS_RCODE_NXDOMAIN)
+ return 0;
+
+ r = dns_transaction_has_positive_answer(t, NULL);
+ if (r <= 0)
+ return r;
+
+ t->answer_rcode = DNS_RCODE_SUCCESS;
+ return 0;
+}
+
+void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
+ usec_t ts;
+ int r;
+
+ assert(t);
+ assert(p);
+ assert(t->scope);
+ assert(t->scope->manager);
+
+ if (t->state != DNS_TRANSACTION_PENDING)
+ return;
+
+ /* Note that this call might invalidate the query. Callers
+ * should hence not attempt to access the query or transaction
+ * after calling this function. */
+
+ log_debug("Processing incoming packet on transaction %" PRIu16".", t->id);
+
+ switch (t->scope->protocol) {
+
+ case DNS_PROTOCOL_LLMNR:
+ /* For LLMNR we will not accept any packets from other interfaces */
+
+ if (p->ifindex != dns_scope_ifindex(t->scope))
+ return;
+
+ if (p->family != t->scope->family)
+ return;
+
+ /* Tentative packets are not full responses but still
+ * useful for identifying uniqueness conflicts during
+ * probing. */
+ if (DNS_PACKET_LLMNR_T(p)) {
+ dns_transaction_tentative(t, p);
+ return;
+ }
+
+ break;
+
+ case DNS_PROTOCOL_MDNS:
+ /* For mDNS we will not accept any packets from other interfaces */
+
+ if (p->ifindex != dns_scope_ifindex(t->scope))
+ return;
+
+ if (p->family != t->scope->family)
+ return;
+
+ break;
+
+ case DNS_PROTOCOL_DNS:
+ /* Note that we do not need to verify the
+ * addresses/port numbers of incoming traffic, as we
+ * invoked connect() on our UDP socket in which case
+ * the kernel already does the needed verification for
+ * us. */
+ break;
+
+ default:
+ assert_not_reached("Invalid DNS protocol.");
+ }
+
+ if (t->received != p) {
+ dns_packet_unref(t->received);
+ t->received = dns_packet_ref(p);
+ }
+
+ t->answer_source = DNS_TRANSACTION_NETWORK;
+
+ if (p->ipproto == IPPROTO_TCP) {
+ if (DNS_PACKET_TC(p)) {
+ /* Truncated via TCP? Somebody must be fucking with us */
+ dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
+ return;
+ }
+
+ if (DNS_PACKET_ID(p) != t->id) {
+ /* Not the reply to our query? Somebody must be fucking with us */
+ dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
+ return;
+ }
+ }
+
+ assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &ts) >= 0);
+
+ switch (t->scope->protocol) {
+
+ case DNS_PROTOCOL_DNS:
+ assert(t->server);
+
+ if (IN_SET(DNS_PACKET_RCODE(p), DNS_RCODE_FORMERR, DNS_RCODE_SERVFAIL, DNS_RCODE_NOTIMP)) {
+
+ /* Request failed, immediately try again with reduced features */
+
+ if (t->current_feature_level <= DNS_SERVER_FEATURE_LEVEL_WORST) {
+ /* This was already at the lowest possible feature level? If so, we can't downgrade
+ * this transaction anymore, hence let's process the response, and accept the rcode. */
+ log_debug("Server returned error: %s", dns_rcode_to_string(DNS_PACKET_RCODE(p)));
+ break;
+ }
+
+ /* Reduce this feature level by one and try again. */
+ t->clamp_feature_level = t->current_feature_level - 1;
+
+ log_debug("Server returned error %s, retrying transaction with reduced feature level %s.",
+ dns_rcode_to_string(DNS_PACKET_RCODE(p)),
+ dns_server_feature_level_to_string(t->clamp_feature_level));
+
+ dns_transaction_retry(t, false /* use the same server */);
+ return;
+ } else if (DNS_PACKET_TC(p))
+ dns_server_packet_truncated(t->server, t->current_feature_level);
+
+ break;
+
+ case DNS_PROTOCOL_LLMNR:
+ case DNS_PROTOCOL_MDNS:
+ dns_scope_packet_received(t->scope, ts - t->start_usec);
+ break;
+
+ default:
+ assert_not_reached("Invalid DNS protocol.");
+ }
+
+ if (DNS_PACKET_TC(p)) {
+
+ /* Truncated packets for mDNS are not allowed. Give up immediately. */
+ if (t->scope->protocol == DNS_PROTOCOL_MDNS) {
+ dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
+ return;
+ }
+
+ log_debug("Reply truncated, retrying via TCP.");
+
+ /* Response was truncated, let's try again with good old TCP */
+ r = dns_transaction_open_tcp(t);
+ if (r == -ESRCH) {
+ /* No servers found? Damn! */
+ dns_transaction_complete(t, DNS_TRANSACTION_NO_SERVERS);
+ return;
+ }
+ if (r == -EOPNOTSUPP) {
+ /* Tried to ask for DNSSEC RRs, on a server that doesn't do DNSSEC */
+ dns_transaction_complete(t, DNS_TRANSACTION_RR_TYPE_UNSUPPORTED);
+ return;
+ }
+ if (r < 0) {
+ /* On LLMNR, if we cannot connect to the host,
+ * we immediately give up */
+ if (t->scope->protocol != DNS_PROTOCOL_DNS)
+ goto fail;
+
+ /* On DNS, couldn't send? Try immediately again, with a new server */
+ dns_transaction_retry(t, true);
+ }
+
+ return;
+ }
+
+ /* After the superficial checks, actually parse the message. */
+ r = dns_packet_extract(p);
+ if (r < 0) {
+ dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
+ return;
+ }
+
+ if (t->server) {
+ /* Report that we successfully received a valid packet with a good rcode after we initially got a bad
+ * rcode and subsequently downgraded the protocol */
+
+ if (IN_SET(DNS_PACKET_RCODE(p), DNS_RCODE_SUCCESS, DNS_RCODE_NXDOMAIN) &&
+ t->clamp_feature_level != _DNS_SERVER_FEATURE_LEVEL_INVALID)
+ dns_server_packet_rcode_downgrade(t->server, t->clamp_feature_level);
+
+ /* Report that the OPT RR was missing */
+ if (!p->opt)
+ dns_server_packet_bad_opt(t->server, t->current_feature_level);
+
+ /* Report that we successfully received a packet */
+ dns_server_packet_received(t->server, p->ipproto, t->current_feature_level, ts - t->start_usec, p->size);
+ }
+
+ /* See if we know things we didn't know before that indicate we better restart the lookup immediately. */
+ r = dns_transaction_maybe_restart(t);
+ if (r < 0)
+ goto fail;
+ if (r > 0) /* Transaction got restarted... */
+ return;
+
+ if (IN_SET(t->scope->protocol, DNS_PROTOCOL_DNS, DNS_PROTOCOL_LLMNR)) {
+
+ /* Only consider responses with equivalent query section to the request */
+ r = dns_packet_is_reply_for(p, t->key);
+ if (r < 0)
+ goto fail;
+ if (r == 0) {
+ dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
+ return;
+ }
+
+ /* Install the answer as answer to the transaction */
+ dns_answer_unref(t->answer);
+ t->answer = dns_answer_ref(p->answer);
+ t->answer_rcode = DNS_PACKET_RCODE(p);
+ t->answer_dnssec_result = _DNSSEC_RESULT_INVALID;
+ t->answer_authenticated = false;
+
+ r = dns_transaction_fix_rcode(t);
+ if (r < 0)
+ goto fail;
+
+ /* Block GC while starting requests for additional DNSSEC RRs */
+ t->block_gc++;
+ r = dns_transaction_request_dnssec_keys(t);
+ t->block_gc--;
+
+ /* Maybe the transaction is ready for GC'ing now? If so, free it and return. */
+ if (!dns_transaction_gc(t))
+ return;
+
+ /* Requesting additional keys might have resulted in
+ * this transaction to fail, since the auxiliary
+ * request failed for some reason. If so, we are not
+ * in pending state anymore, and we should exit
+ * quickly. */
+ if (t->state != DNS_TRANSACTION_PENDING)
+ return;
+ if (r < 0)
+ goto fail;
+ if (r > 0) {
+ /* There are DNSSEC transactions pending now. Update the state accordingly. */
+ t->state = DNS_TRANSACTION_VALIDATING;
+ dns_transaction_close_connection(t);
+ dns_transaction_stop_timeout(t);
+ return;
+ }
+ }
+
+ dns_transaction_process_dnssec(t);
+ return;
+
+fail:
+ t->answer_errno = -r;
+ dns_transaction_complete(t, DNS_TRANSACTION_ERRNO);
+}
+
+static int on_dns_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ DnsTransaction *t = userdata;
+ int r;
+
+ assert(t);
+ assert(t->scope);
+
+ r = manager_recv(t->scope->manager, fd, DNS_PROTOCOL_DNS, &p);
+ if (ERRNO_IS_DISCONNECT(-r)) {
+ usec_t usec;
+
+ /* UDP connection failure get reported via ICMP and then are possible delivered to us on the next
+ * recvmsg(). Treat this like a lost packet. */
+
+ log_debug_errno(r, "Connection failure for DNS UDP packet: %m");
+ assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &usec) >= 0);
+ dns_server_packet_lost(t->server, IPPROTO_UDP, t->current_feature_level, usec - t->start_usec);
+
+ dns_transaction_retry(t, true);
+ return 0;
+ }
+ if (r < 0) {
+ dns_transaction_complete(t, DNS_TRANSACTION_ERRNO);
+ t->answer_errno = -r;
+ return 0;
+ }
+
+ r = dns_packet_validate_reply(p);
+ if (r < 0) {
+ log_debug_errno(r, "Received invalid DNS packet as response, ignoring: %m");
+ return 0;
+ }
+ if (r == 0) {
+ log_debug("Received inappropriate DNS packet as response, ignoring.");
+ return 0;
+ }
+
+ if (DNS_PACKET_ID(p) != t->id) {
+ log_debug("Received packet with incorrect transaction ID, ignoring.");
+ return 0;
+ }
+
+ dns_transaction_process_reply(t, p);
+ return 0;
+}
+
+static int dns_transaction_emit_udp(DnsTransaction *t) {
+ int r;
+
+ assert(t);
+
+ if (t->scope->protocol == DNS_PROTOCOL_DNS) {
+
+ r = dns_transaction_pick_server(t);
+ if (r < 0)
+ return r;
+
+ if (t->current_feature_level < DNS_SERVER_FEATURE_LEVEL_UDP)
+ return -EAGAIN;
+
+ if (!dns_server_dnssec_supported(t->server) && dns_type_is_dnssec(t->key->type))
+ return -EOPNOTSUPP;
+
+ if (r > 0 || t->dns_udp_fd < 0) { /* Server changed, or no connection yet. */
+ int fd;
+
+ dns_transaction_close_connection(t);
+
+ fd = dns_scope_socket_udp(t->scope, t->server, 53);
+ if (fd < 0)
+ return fd;
+
+ r = sd_event_add_io(t->scope->manager->event, &t->dns_udp_event_source, fd, EPOLLIN, on_dns_packet, t);
+ if (r < 0) {
+ safe_close(fd);
+ return r;
+ }
+
+ (void) sd_event_source_set_description(t->dns_udp_event_source, "dns-transaction-udp");
+ t->dns_udp_fd = fd;
+ }
+
+ r = dns_server_adjust_opt(t->server, t->sent, t->current_feature_level);
+ if (r < 0)
+ return r;
+ } else
+ dns_transaction_close_connection(t);
+
+ r = dns_scope_emit_udp(t->scope, t->dns_udp_fd, t->sent);
+ if (r < 0)
+ return r;
+
+ dns_transaction_reset_answer(t);
+
+ return 0;
+}
+
+static int on_transaction_timeout(sd_event_source *s, usec_t usec, void *userdata) {
+ DnsTransaction *t = userdata;
+
+ assert(s);
+ assert(t);
+
+ if (!t->initial_jitter_scheduled || t->initial_jitter_elapsed) {
+ /* Timeout reached? Increase the timeout for the server used */
+ switch (t->scope->protocol) {
+
+ case DNS_PROTOCOL_DNS:
+ assert(t->server);
+ dns_server_packet_lost(t->server, t->stream ? IPPROTO_TCP : IPPROTO_UDP, t->current_feature_level, usec - t->start_usec);
+ break;
+
+ case DNS_PROTOCOL_LLMNR:
+ case DNS_PROTOCOL_MDNS:
+ dns_scope_packet_lost(t->scope, usec - t->start_usec);
+ break;
+
+ default:
+ assert_not_reached("Invalid DNS protocol.");
+ }
+
+ if (t->initial_jitter_scheduled)
+ t->initial_jitter_elapsed = true;
+ }
+
+ log_debug("Timeout reached on transaction %" PRIu16 ".", t->id);
+
+ dns_transaction_retry(t, true);
+ return 0;
+}
+
+static usec_t transaction_get_resend_timeout(DnsTransaction *t) {
+ assert(t);
+ assert(t->scope);
+
+ switch (t->scope->protocol) {
+
+ case DNS_PROTOCOL_DNS:
+ assert(t->server);
+ return t->server->resend_timeout;
+
+ case DNS_PROTOCOL_MDNS:
+ assert(t->n_attempts > 0);
+ return (1 << (t->n_attempts - 1)) * USEC_PER_SEC;
+
+ case DNS_PROTOCOL_LLMNR:
+ return t->scope->resend_timeout;
+
+ default:
+ assert_not_reached("Invalid DNS protocol.");
+ }
+}
+
+static int dns_transaction_prepare(DnsTransaction *t, usec_t ts) {
+ int r;
+
+ assert(t);
+
+ dns_transaction_stop_timeout(t);
+
+ r = dns_scope_network_good(t->scope);
+ if (r < 0)
+ return r;
+ if (r == 0) {
+ dns_transaction_complete(t, DNS_TRANSACTION_NETWORK_DOWN);
+ return 0;
+ }
+
+ if (t->n_attempts >= TRANSACTION_ATTEMPTS_MAX(t->scope->protocol)) {
+ dns_transaction_complete(t, DNS_TRANSACTION_ATTEMPTS_MAX_REACHED);
+ return 0;
+ }
+
+ if (t->scope->protocol == DNS_PROTOCOL_LLMNR && t->tried_stream) {
+ /* If we already tried via a stream, then we don't
+ * retry on LLMNR. See RFC 4795, Section 2.7. */
+ dns_transaction_complete(t, DNS_TRANSACTION_ATTEMPTS_MAX_REACHED);
+ return 0;
+ }
+
+ t->n_attempts++;
+ t->start_usec = ts;
+
+ dns_transaction_reset_answer(t);
+ dns_transaction_flush_dnssec_transactions(t);
+
+ /* Check the trust anchor. Do so only on classic DNS, since DNSSEC does not apply otherwise. */
+ if (t->scope->protocol == DNS_PROTOCOL_DNS) {
+ r = dns_trust_anchor_lookup_positive(&t->scope->manager->trust_anchor, t->key, &t->answer);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ t->answer_rcode = DNS_RCODE_SUCCESS;
+ t->answer_source = DNS_TRANSACTION_TRUST_ANCHOR;
+ t->answer_authenticated = true;
+ dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);
+ return 0;
+ }
+
+ if (dns_name_is_root(dns_resource_key_name(t->key)) &&
+ t->key->type == DNS_TYPE_DS) {
+
+ /* Hmm, this is a request for the root DS? A
+ * DS RR doesn't exist in the root zone, and
+ * if our trust anchor didn't know it either,
+ * this means we cannot do any DNSSEC logic
+ * anymore. */
+
+ if (t->scope->dnssec_mode == DNSSEC_ALLOW_DOWNGRADE) {
+ /* We are in downgrade mode. In this
+ * case, synthesize an unsigned empty
+ * response, so that the any lookup
+ * depending on this one can continue
+ * assuming there was no DS, and hence
+ * the root zone was unsigned. */
+
+ t->answer_rcode = DNS_RCODE_SUCCESS;
+ t->answer_source = DNS_TRANSACTION_TRUST_ANCHOR;
+ t->answer_authenticated = false;
+ dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);
+ } else
+ /* If we are not in downgrade mode,
+ * then fail the lookup, because we
+ * cannot reasonably answer it. There
+ * might be DS RRs, but we don't know
+ * them, and the DNS server won't tell
+ * them to us (and even if it would,
+ * we couldn't validate and trust them. */
+ dns_transaction_complete(t, DNS_TRANSACTION_NO_TRUST_ANCHOR);
+
+ return 0;
+ }
+ }
+
+ /* Check the zone, but only if this transaction is not used
+ * for probing or verifying a zone item. */
+ if (set_isempty(t->notify_zone_items)) {
+
+ r = dns_zone_lookup(&t->scope->zone, t->key, dns_scope_ifindex(t->scope), &t->answer, NULL, NULL);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ t->answer_rcode = DNS_RCODE_SUCCESS;
+ t->answer_source = DNS_TRANSACTION_ZONE;
+ t->answer_authenticated = true;
+ dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);
+ return 0;
+ }
+ }
+
+ /* Check the cache, but only if this transaction is not used
+ * for probing or verifying a zone item. */
+ if (set_isempty(t->notify_zone_items)) {
+
+ /* Before trying the cache, let's make sure we figured out a
+ * server to use. Should this cause a change of server this
+ * might flush the cache. */
+ dns_scope_get_dns_server(t->scope);
+
+ /* Let's then prune all outdated entries */
+ dns_cache_prune(&t->scope->cache);
+
+ r = dns_cache_lookup(&t->scope->cache, t->key, t->clamp_ttl, &t->answer_rcode, &t->answer, &t->answer_authenticated);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ t->answer_source = DNS_TRANSACTION_CACHE;
+ if (t->answer_rcode == DNS_RCODE_SUCCESS)
+ dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);
+ else
+ dns_transaction_complete(t, DNS_TRANSACTION_RCODE_FAILURE);
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+static int dns_transaction_make_packet_mdns(DnsTransaction *t) {
+
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ bool add_known_answers = false;
+ DnsTransaction *other;
+ unsigned qdcount;
+ usec_t ts;
+ int r;
+
+ assert(t);
+ assert(t->scope->protocol == DNS_PROTOCOL_MDNS);
+
+ /* Discard any previously prepared packet, so we can start over and coalesce again */
+ t->sent = dns_packet_unref(t->sent);
+
+ r = dns_packet_new_query(&p, t->scope->protocol, 0, false);
+ if (r < 0)
+ return r;
+
+ r = dns_packet_append_key(p, t->key, NULL);
+ if (r < 0)
+ return r;
+
+ qdcount = 1;
+
+ if (dns_key_is_shared(t->key))
+ add_known_answers = true;
+
+ /*
+ * For mDNS, we want to coalesce as many open queries in pending transactions into one single
+ * query packet on the wire as possible. To achieve that, we iterate through all pending transactions
+ * in our current scope, and see whether their timing contraints allow them to be sent.
+ */
+
+ assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &ts) >= 0);
+
+ LIST_FOREACH(transactions_by_scope, other, t->scope->transactions) {
+
+ /* Skip ourselves */
+ if (other == t)
+ continue;
+
+ if (other->state != DNS_TRANSACTION_PENDING)
+ continue;
+
+ if (other->next_attempt_after > ts)
+ continue;
+
+ if (qdcount >= UINT16_MAX)
+ break;
+
+ r = dns_packet_append_key(p, other->key, NULL);
+
+ /*
+ * If we can't stuff more questions into the packet, just give up.
+ * One of the 'other' transactions will fire later and take care of the rest.
+ */
+ if (r == -EMSGSIZE)
+ break;
+
+ if (r < 0)
+ return r;
+
+ r = dns_transaction_prepare(other, ts);
+ if (r <= 0)
+ continue;
+
+ ts += transaction_get_resend_timeout(other);
+
+ r = sd_event_add_time(
+ other->scope->manager->event,
+ &other->timeout_event_source,
+ clock_boottime_or_monotonic(),
+ ts, 0,
+ on_transaction_timeout, other);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_source_set_description(t->timeout_event_source, "dns-transaction-timeout");
+
+ other->state = DNS_TRANSACTION_PENDING;
+ other->next_attempt_after = ts;
+
+ qdcount++;
+
+ if (dns_key_is_shared(other->key))
+ add_known_answers = true;
+ }
+
+ DNS_PACKET_HEADER(p)->qdcount = htobe16(qdcount);
+
+ /* Append known answer section if we're asking for any shared record */
+ if (add_known_answers) {
+ r = dns_cache_export_shared_to_packet(&t->scope->cache, p);
+ if (r < 0)
+ return r;
+ }
+
+ t->sent = p;
+ p = NULL;
+
+ return 0;
+}
+
+static int dns_transaction_make_packet(DnsTransaction *t) {
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ int r;
+
+ assert(t);
+
+ if (t->scope->protocol == DNS_PROTOCOL_MDNS)
+ return dns_transaction_make_packet_mdns(t);
+
+ if (t->sent)
+ return 0;
+
+ r = dns_packet_new_query(&p, t->scope->protocol, 0, t->scope->dnssec_mode != DNSSEC_NO);
+ if (r < 0)
+ return r;
+
+ r = dns_packet_append_key(p, t->key, NULL);
+ if (r < 0)
+ return r;
+
+ DNS_PACKET_HEADER(p)->qdcount = htobe16(1);
+ DNS_PACKET_HEADER(p)->id = t->id;
+
+ t->sent = p;
+ p = NULL;
+
+ return 0;
+}
+
+int dns_transaction_go(DnsTransaction *t) {
+ usec_t ts;
+ int r;
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
+
+ assert(t);
+
+ /* Returns > 0 if the transaction is now pending, returns 0 if could be processed immediately and has finished
+ * now. */
+
+ assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &ts) >= 0);
+
+ r = dns_transaction_prepare(t, ts);
+ if (r <= 0)
+ return r;
+
+ log_debug("Transaction %" PRIu16 " for <%s> scope %s on %s/%s.",
+ t->id,
+ dns_resource_key_to_string(t->key, key_str, sizeof key_str),
+ dns_protocol_to_string(t->scope->protocol),
+ t->scope->link ? t->scope->link->name : "*",
+ af_to_name_short(t->scope->family));
+
+ if (!t->initial_jitter_scheduled &&
+ (t->scope->protocol == DNS_PROTOCOL_LLMNR ||
+ t->scope->protocol == DNS_PROTOCOL_MDNS)) {
+ usec_t jitter, accuracy;
+
+ /* RFC 4795 Section 2.7 suggests all queries should be
+ * delayed by a random time from 0 to JITTER_INTERVAL. */
+
+ t->initial_jitter_scheduled = true;
+
+ random_bytes(&jitter, sizeof(jitter));
+
+ switch (t->scope->protocol) {
+
+ case DNS_PROTOCOL_LLMNR:
+ jitter %= LLMNR_JITTER_INTERVAL_USEC;
+ accuracy = LLMNR_JITTER_INTERVAL_USEC;
+ break;
+
+ case DNS_PROTOCOL_MDNS:
+ jitter %= MDNS_JITTER_RANGE_USEC;
+ jitter += MDNS_JITTER_MIN_USEC;
+ accuracy = MDNS_JITTER_RANGE_USEC;
+ break;
+ default:
+ assert_not_reached("bad protocol");
+ }
+
+ r = sd_event_add_time(
+ t->scope->manager->event,
+ &t->timeout_event_source,
+ clock_boottime_or_monotonic(),
+ ts + jitter, accuracy,
+ on_transaction_timeout, t);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_source_set_description(t->timeout_event_source, "dns-transaction-timeout");
+
+ t->n_attempts = 0;
+ t->next_attempt_after = ts;
+ t->state = DNS_TRANSACTION_PENDING;
+
+ log_debug("Delaying %s transaction for " USEC_FMT "us.", dns_protocol_to_string(t->scope->protocol), jitter);
+ return 0;
+ }
+
+ /* Otherwise, we need to ask the network */
+ r = dns_transaction_make_packet(t);
+ if (r < 0)
+ return r;
+
+ if (t->scope->protocol == DNS_PROTOCOL_LLMNR &&
+ (dns_name_endswith(dns_resource_key_name(t->key), "in-addr.arpa") > 0 ||
+ dns_name_endswith(dns_resource_key_name(t->key), "ip6.arpa") > 0)) {
+
+ /* RFC 4795, Section 2.4. says reverse lookups shall
+ * always be made via TCP on LLMNR */
+ r = dns_transaction_open_tcp(t);
+ } else {
+ /* Try via UDP, and if that fails due to large size or lack of
+ * support try via TCP */
+ r = dns_transaction_emit_udp(t);
+ if (r == -EMSGSIZE)
+ log_debug("Sending query via TCP since it is too large.");
+ if (r == -EAGAIN)
+ log_debug("Sending query via TCP since server doesn't support UDP.");
+ if (r == -EMSGSIZE || r == -EAGAIN)
+ r = dns_transaction_open_tcp(t);
+ }
+
+ if (r == -ESRCH) {
+ /* No servers to send this to? */
+ dns_transaction_complete(t, DNS_TRANSACTION_NO_SERVERS);
+ return 0;
+ }
+ if (r == -EOPNOTSUPP) {
+ /* Tried to ask for DNSSEC RRs, on a server that doesn't do DNSSEC */
+ dns_transaction_complete(t, DNS_TRANSACTION_RR_TYPE_UNSUPPORTED);
+ return 0;
+ }
+ if (t->scope->protocol == DNS_PROTOCOL_LLMNR && ERRNO_IS_DISCONNECT(-r)) {
+ /* On LLMNR, if we cannot connect to a host via TCP when doing reverse lookups. This means we cannot
+ * answer this request with this protocol. */
+ dns_transaction_complete(t, DNS_TRANSACTION_NOT_FOUND);
+ return 0;
+ }
+ if (r < 0) {
+ if (t->scope->protocol != DNS_PROTOCOL_DNS)
+ return r;
+
+ /* Couldn't send? Try immediately again, with a new server */
+ dns_scope_next_dns_server(t->scope);
+
+ return dns_transaction_go(t);
+ }
+
+ ts += transaction_get_resend_timeout(t);
+
+ r = sd_event_add_time(
+ t->scope->manager->event,
+ &t->timeout_event_source,
+ clock_boottime_or_monotonic(),
+ ts, 0,
+ on_transaction_timeout, t);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_source_set_description(t->timeout_event_source, "dns-transaction-timeout");
+
+ t->state = DNS_TRANSACTION_PENDING;
+ t->next_attempt_after = ts;
+
+ return 1;
+}
+
+static int dns_transaction_find_cyclic(DnsTransaction *t, DnsTransaction *aux) {
+ DnsTransaction *n;
+ Iterator i;
+ int r;
+
+ assert(t);
+ assert(aux);
+
+ /* Try to find cyclic dependencies between transaction objects */
+
+ if (t == aux)
+ return 1;
+
+ SET_FOREACH(n, aux->dnssec_transactions, i) {
+ r = dns_transaction_find_cyclic(t, n);
+ if (r != 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static int dns_transaction_add_dnssec_transaction(DnsTransaction *t, DnsResourceKey *key, DnsTransaction **ret) {
+ DnsTransaction *aux;
+ int r;
+
+ assert(t);
+ assert(ret);
+ assert(key);
+
+ aux = dns_scope_find_transaction(t->scope, key, true);
+ if (!aux) {
+ r = dns_transaction_new(&aux, t->scope, key);
+ if (r < 0)
+ return r;
+ } else {
+ if (set_contains(t->dnssec_transactions, aux)) {
+ *ret = aux;
+ return 0;
+ }
+
+ r = dns_transaction_find_cyclic(t, aux);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ char s[DNS_RESOURCE_KEY_STRING_MAX], saux[DNS_RESOURCE_KEY_STRING_MAX];
+
+ log_debug("Potential cyclic dependency, refusing to add transaction %" PRIu16 " (%s) as dependency for %" PRIu16 " (%s).",
+ aux->id,
+ dns_resource_key_to_string(t->key, s, sizeof s),
+ t->id,
+ dns_resource_key_to_string(aux->key, saux, sizeof saux));
+
+ return -ELOOP;
+ }
+ }
+
+ r = set_ensure_allocated(&t->dnssec_transactions, NULL);
+ if (r < 0)
+ goto gc;
+
+ r = set_ensure_allocated(&aux->notify_transactions, NULL);
+ if (r < 0)
+ goto gc;
+
+ r = set_ensure_allocated(&aux->notify_transactions_done, NULL);
+ if (r < 0)
+ goto gc;
+
+ r = set_put(t->dnssec_transactions, aux);
+ if (r < 0)
+ goto gc;
+
+ r = set_put(aux->notify_transactions, t);
+ if (r < 0) {
+ (void) set_remove(t->dnssec_transactions, aux);
+ goto gc;
+ }
+
+ *ret = aux;
+ return 1;
+
+gc:
+ dns_transaction_gc(aux);
+ return r;
+}
+
+static int dns_transaction_request_dnssec_rr(DnsTransaction *t, DnsResourceKey *key) {
+ _cleanup_(dns_answer_unrefp) DnsAnswer *a = NULL;
+ DnsTransaction *aux;
+ int r;
+
+ assert(t);
+ assert(key);
+
+ /* Try to get the data from the trust anchor */
+ r = dns_trust_anchor_lookup_positive(&t->scope->manager->trust_anchor, key, &a);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ r = dns_answer_extend(&t->validated_keys, a);
+ if (r < 0)
+ return r;
+
+ return 0;
+ }
+
+ /* This didn't work, ask for it via the network/cache then. */
+ r = dns_transaction_add_dnssec_transaction(t, key, &aux);
+ if (r == -ELOOP) /* This would result in a cyclic dependency */
+ return 0;
+ if (r < 0)
+ return r;
+
+ if (aux->state == DNS_TRANSACTION_NULL) {
+ r = dns_transaction_go(aux);
+ if (r < 0)
+ return r;
+ }
+
+ return 1;
+}
+
+static int dns_transaction_negative_trust_anchor_lookup(DnsTransaction *t, const char *name) {
+ int r;
+
+ assert(t);
+
+ /* Check whether the specified name is in the NTA
+ * database, either in the global one, or the link-local
+ * one. */
+
+ r = dns_trust_anchor_lookup_negative(&t->scope->manager->trust_anchor, name);
+ if (r != 0)
+ return r;
+
+ if (!t->scope->link)
+ return 0;
+
+ return set_contains(t->scope->link->dnssec_negative_trust_anchors, name);
+}
+
+static int dns_transaction_has_unsigned_negative_answer(DnsTransaction *t) {
+ int r;
+
+ assert(t);
+
+ /* Checks whether the answer is negative, and lacks NSEC/NSEC3
+ * RRs to prove it */
+
+ r = dns_transaction_has_positive_answer(t, NULL);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return false;
+
+ /* Is this key explicitly listed as a negative trust anchor?
+ * If so, it's nothing we need to care about */
+ r = dns_transaction_negative_trust_anchor_lookup(t, dns_resource_key_name(t->key));
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return false;
+
+ /* The answer does not contain any RRs that match to the
+ * question. If so, let's see if there are any NSEC/NSEC3 RRs
+ * included. If not, the answer is unsigned. */
+
+ r = dns_answer_contains_nsec_or_nsec3(t->answer);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return false;
+
+ return true;
+}
+
+static int dns_transaction_is_primary_response(DnsTransaction *t, DnsResourceRecord *rr) {
+ int r;
+
+ assert(t);
+ assert(rr);
+
+ /* Check if the specified RR is the "primary" response,
+ * i.e. either matches the question precisely or is a
+ * CNAME/DNAME for it. */
+
+ r = dns_resource_key_match_rr(t->key, rr, NULL);
+ if (r != 0)
+ return r;
+
+ return dns_resource_key_match_cname_or_dname(t->key, rr->key, NULL);
+}
+
+static bool dns_transaction_dnssec_supported(DnsTransaction *t) {
+ assert(t);
+
+ /* Checks whether our transaction's DNS server is assumed to be compatible with DNSSEC. Returns false as soon
+ * as we changed our mind about a server, and now believe it is incompatible with DNSSEC. */
+
+ if (t->scope->protocol != DNS_PROTOCOL_DNS)
+ return false;
+
+ /* If we have picked no server, then we are working from the cache or some other source, and DNSSEC might well
+ * be supported, hence return true. */
+ if (!t->server)
+ return true;
+
+ /* Note that we do not check the feature level actually used for the transaction but instead the feature level
+ * the server is known to support currently, as the transaction feature level might be lower than what the
+ * server actually supports, since we might have downgraded this transaction's feature level because we got a
+ * SERVFAIL earlier and wanted to check whether downgrading fixes it. */
+
+ return dns_server_dnssec_supported(t->server);
+}
+
+static bool dns_transaction_dnssec_supported_full(DnsTransaction *t) {
+ DnsTransaction *dt;
+ Iterator i;
+
+ assert(t);
+
+ /* Checks whether our transaction our any of the auxiliary transactions couldn't do DNSSEC. */
+
+ if (!dns_transaction_dnssec_supported(t))
+ return false;
+
+ SET_FOREACH(dt, t->dnssec_transactions, i)
+ if (!dns_transaction_dnssec_supported(dt))
+ return false;
+
+ return true;
+}
+
+int dns_transaction_request_dnssec_keys(DnsTransaction *t) {
+ DnsResourceRecord *rr;
+
+ int r;
+
+ assert(t);
+
+ /*
+ * Retrieve all auxiliary RRs for the answer we got, so that
+ * we can verify signatures or prove that RRs are rightfully
+ * unsigned. Specifically:
+ *
+ * - For RRSIG we get the matching DNSKEY
+ * - For DNSKEY we get the matching DS
+ * - For unsigned SOA/NS we get the matching DS
+ * - For unsigned CNAME/DNAME/DS we get the parent SOA RR
+ * - For other unsigned RRs we get the matching SOA RR
+ * - For SOA/NS queries with no matching response RR, and no NSEC/NSEC3, the DS RR
+ * - For DS queries with no matching response RRs, and no NSEC/NSEC3, the parent's SOA RR
+ * - For other queries with no matching response RRs, and no NSEC/NSEC3, the SOA RR
+ */
+
+ if (t->scope->dnssec_mode == DNSSEC_NO)
+ return 0;
+ if (t->answer_source != DNS_TRANSACTION_NETWORK)
+ return 0; /* We only need to validate stuff from the network */
+ if (!dns_transaction_dnssec_supported(t))
+ return 0; /* If we can't do DNSSEC anyway there's no point in geting the auxiliary RRs */
+
+ DNS_ANSWER_FOREACH(rr, t->answer) {
+
+ if (dns_type_is_pseudo(rr->key->type))
+ continue;
+
+ /* If this RR is in the negative trust anchor, we don't need to validate it. */
+ r = dns_transaction_negative_trust_anchor_lookup(t, dns_resource_key_name(rr->key));
+ if (r < 0)
+ return r;
+ if (r > 0)
+ continue;
+
+ switch (rr->key->type) {
+
+ case DNS_TYPE_RRSIG: {
+ /* For each RRSIG we request the matching DNSKEY */
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *dnskey = NULL;
+
+ /* If this RRSIG is about a DNSKEY RR and the
+ * signer is the same as the owner, then we
+ * already have the DNSKEY, and we don't have
+ * to look for more. */
+ if (rr->rrsig.type_covered == DNS_TYPE_DNSKEY) {
+ r = dns_name_equal(rr->rrsig.signer, dns_resource_key_name(rr->key));
+ if (r < 0)
+ return r;
+ if (r > 0)
+ continue;
+ }
+
+ /* If the signer is not a parent of our
+ * original query, then this is about an
+ * auxiliary RRset, but not anything we asked
+ * for. In this case we aren't interested,
+ * because we don't want to request additional
+ * RRs for stuff we didn't really ask for, and
+ * also to avoid request loops, where
+ * additional RRs from one transaction result
+ * in another transaction whose additonal RRs
+ * point back to the original transaction, and
+ * we deadlock. */
+ r = dns_name_endswith(dns_resource_key_name(t->key), rr->rrsig.signer);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ dnskey = dns_resource_key_new(rr->key->class, DNS_TYPE_DNSKEY, rr->rrsig.signer);
+ if (!dnskey)
+ return -ENOMEM;
+
+ log_debug("Requesting DNSKEY to validate transaction %" PRIu16" (%s, RRSIG with key tag: %" PRIu16 ").",
+ t->id, dns_resource_key_name(rr->key), rr->rrsig.key_tag);
+ r = dns_transaction_request_dnssec_rr(t, dnskey);
+ if (r < 0)
+ return r;
+ break;
+ }
+
+ case DNS_TYPE_DNSKEY: {
+ /* For each DNSKEY we request the matching DS */
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *ds = NULL;
+
+ /* If the DNSKEY we are looking at is not for
+ * zone we are interested in, nor any of its
+ * parents, we aren't interested, and don't
+ * request it. After all, we don't want to end
+ * up in request loops, and want to keep
+ * additional traffic down. */
+
+ r = dns_name_endswith(dns_resource_key_name(t->key), dns_resource_key_name(rr->key));
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ ds = dns_resource_key_new(rr->key->class, DNS_TYPE_DS, dns_resource_key_name(rr->key));
+ if (!ds)
+ return -ENOMEM;
+
+ log_debug("Requesting DS to validate transaction %" PRIu16" (%s, DNSKEY with key tag: %" PRIu16 ").",
+ t->id, dns_resource_key_name(rr->key), dnssec_keytag(rr, false));
+ r = dns_transaction_request_dnssec_rr(t, ds);
+ if (r < 0)
+ return r;
+
+ break;
+ }
+
+ case DNS_TYPE_SOA:
+ case DNS_TYPE_NS: {
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *ds = NULL;
+
+ /* For an unsigned SOA or NS, try to acquire
+ * the matching DS RR, as we are at a zone cut
+ * then, and whether a DS exists tells us
+ * whether the zone is signed. Do so only if
+ * this RR matches our original question,
+ * however. */
+
+ r = dns_resource_key_match_rr(t->key, rr, NULL);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ r = dnssec_has_rrsig(t->answer, rr->key);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ continue;
+
+ ds = dns_resource_key_new(rr->key->class, DNS_TYPE_DS, dns_resource_key_name(rr->key));
+ if (!ds)
+ return -ENOMEM;
+
+ log_debug("Requesting DS to validate transaction %" PRIu16 " (%s, unsigned SOA/NS RRset).",
+ t->id, dns_resource_key_name(rr->key));
+ r = dns_transaction_request_dnssec_rr(t, ds);
+ if (r < 0)
+ return r;
+
+ break;
+ }
+
+ case DNS_TYPE_DS:
+ case DNS_TYPE_CNAME:
+ case DNS_TYPE_DNAME: {
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *soa = NULL;
+ const char *name;
+
+ /* CNAMEs and DNAMEs cannot be located at a
+ * zone apex, hence ask for the parent SOA for
+ * unsigned CNAME/DNAME RRs, maybe that's the
+ * apex. But do all that only if this is
+ * actually a response to our original
+ * question.
+ *
+ * Similar for DS RRs, which are signed when
+ * the parent SOA is signed. */
+
+ r = dns_transaction_is_primary_response(t, rr);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ r = dnssec_has_rrsig(t->answer, rr->key);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ continue;
+
+ r = dns_answer_has_dname_for_cname(t->answer, rr);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ continue;
+
+ name = dns_resource_key_name(rr->key);
+ r = dns_name_parent(&name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ soa = dns_resource_key_new(rr->key->class, DNS_TYPE_SOA, name);
+ if (!soa)
+ return -ENOMEM;
+
+ log_debug("Requesting parent SOA to validate transaction %" PRIu16 " (%s, unsigned CNAME/DNAME/DS RRset).",
+ t->id, dns_resource_key_name(rr->key));
+ r = dns_transaction_request_dnssec_rr(t, soa);
+ if (r < 0)
+ return r;
+
+ break;
+ }
+
+ default: {
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *soa = NULL;
+
+ /* For other unsigned RRsets (including
+ * NSEC/NSEC3!), look for proof the zone is
+ * unsigned, by requesting the SOA RR of the
+ * zone. However, do so only if they are
+ * directly relevant to our original
+ * question. */
+
+ r = dns_transaction_is_primary_response(t, rr);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ r = dnssec_has_rrsig(t->answer, rr->key);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ continue;
+
+ soa = dns_resource_key_new(rr->key->class, DNS_TYPE_SOA, dns_resource_key_name(rr->key));
+ if (!soa)
+ return -ENOMEM;
+
+ log_debug("Requesting SOA to validate transaction %" PRIu16 " (%s, unsigned non-SOA/NS RRset <%s>).",
+ t->id, dns_resource_key_name(rr->key), dns_resource_record_to_string(rr));
+ r = dns_transaction_request_dnssec_rr(t, soa);
+ if (r < 0)
+ return r;
+ break;
+ }}
+ }
+
+ /* Above, we requested everything necessary to validate what
+ * we got. Now, let's request what we need to validate what we
+ * didn't get... */
+
+ r = dns_transaction_has_unsigned_negative_answer(t);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ const char *name;
+ uint16_t type = 0;
+
+ name = dns_resource_key_name(t->key);
+
+ /* If this was a SOA or NS request, then check if there's a DS RR for the same domain. Note that this
+ * could also be used as indication that we are not at a zone apex, but in real world setups there are
+ * too many broken DNS servers (Hello, incapdns.net!) where non-terminal zones return NXDOMAIN even
+ * though they have further children. If this was a DS request, then it's signed when the parent zone
+ * is signed, hence ask the parent SOA in that case. If this was any other RR then ask for the SOA RR,
+ * to see if that is signed. */
+
+ if (t->key->type == DNS_TYPE_DS) {
+ r = dns_name_parent(&name);
+ if (r > 0) {
+ type = DNS_TYPE_SOA;
+ log_debug("Requesting parent SOA to validate transaction %" PRIu16 " (%s, unsigned empty DS response).",
+ t->id, dns_resource_key_name(t->key));
+ } else
+ name = NULL;
+
+ } else if (IN_SET(t->key->type, DNS_TYPE_SOA, DNS_TYPE_NS)) {
+
+ type = DNS_TYPE_DS;
+ log_debug("Requesting DS to validate transaction %" PRIu16 " (%s, unsigned empty SOA/NS response).",
+ t->id, dns_resource_key_name(t->key));
+
+ } else {
+ type = DNS_TYPE_SOA;
+ log_debug("Requesting SOA to validate transaction %" PRIu16 " (%s, unsigned empty non-SOA/NS/DS response).",
+ t->id, dns_resource_key_name(t->key));
+ }
+
+ if (name) {
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *soa = NULL;
+
+ soa = dns_resource_key_new(t->key->class, type, name);
+ if (!soa)
+ return -ENOMEM;
+
+ r = dns_transaction_request_dnssec_rr(t, soa);
+ if (r < 0)
+ return r;
+ }
+ }
+
+ return dns_transaction_dnssec_is_live(t);
+}
+
+void dns_transaction_notify(DnsTransaction *t, DnsTransaction *source) {
+ assert(t);
+ assert(source);
+
+ /* Invoked whenever any of our auxiliary DNSSEC transactions completed its work. If the state is still PENDING,
+ we are still in the loop that adds further DNSSEC transactions, hence don't check if we are ready yet. If
+ the state is VALIDATING however, we should check if we are complete now. */
+
+ if (t->state == DNS_TRANSACTION_VALIDATING)
+ dns_transaction_process_dnssec(t);
+}
+
+static int dns_transaction_validate_dnskey_by_ds(DnsTransaction *t) {
+ DnsResourceRecord *rr;
+ int ifindex, r;
+
+ assert(t);
+
+ /* Add all DNSKEY RRs from the answer that are validated by DS
+ * RRs from the list of validated keys to the list of
+ * validated keys. */
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, t->answer) {
+
+ r = dnssec_verify_dnskey_by_ds_search(rr, t->validated_keys);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ /* If so, the DNSKEY is validated too. */
+ r = dns_answer_add_extend(&t->validated_keys, rr, ifindex, DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static int dns_transaction_requires_rrsig(DnsTransaction *t, DnsResourceRecord *rr) {
+ int r;
+
+ assert(t);
+ assert(rr);
+
+ /* Checks if the RR we are looking for must be signed with an
+ * RRSIG. This is used for positive responses. */
+
+ if (t->scope->dnssec_mode == DNSSEC_NO)
+ return false;
+
+ if (dns_type_is_pseudo(rr->key->type))
+ return -EINVAL;
+
+ r = dns_transaction_negative_trust_anchor_lookup(t, dns_resource_key_name(rr->key));
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return false;
+
+ switch (rr->key->type) {
+
+ case DNS_TYPE_RRSIG:
+ /* RRSIGs are the signatures themselves, they need no signing. */
+ return false;
+
+ case DNS_TYPE_SOA:
+ case DNS_TYPE_NS: {
+ DnsTransaction *dt;
+ Iterator i;
+
+ /* For SOA or NS RRs we look for a matching DS transaction */
+
+ SET_FOREACH(dt, t->dnssec_transactions, i) {
+
+ if (dt->key->class != rr->key->class)
+ continue;
+ if (dt->key->type != DNS_TYPE_DS)
+ continue;
+
+ r = dns_name_equal(dns_resource_key_name(dt->key), dns_resource_key_name(rr->key));
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ /* We found a DS transactions for the SOA/NS
+ * RRs we are looking at. If it discovered signed DS
+ * RRs, then we need to be signed, too. */
+
+ if (!dt->answer_authenticated)
+ return false;
+
+ return dns_answer_match_key(dt->answer, dt->key, NULL);
+ }
+
+ /* We found nothing that proves this is safe to leave
+ * this unauthenticated, hence ask inist on
+ * authentication. */
+ return true;
+ }
+
+ case DNS_TYPE_DS:
+ case DNS_TYPE_CNAME:
+ case DNS_TYPE_DNAME: {
+ const char *parent = NULL;
+ DnsTransaction *dt;
+ Iterator i;
+
+ /*
+ * CNAME/DNAME RRs cannot be located at a zone apex, hence look directly for the parent SOA.
+ *
+ * DS RRs are signed if the parent is signed, hence also look at the parent SOA
+ */
+
+ SET_FOREACH(dt, t->dnssec_transactions, i) {
+
+ if (dt->key->class != rr->key->class)
+ continue;
+ if (dt->key->type != DNS_TYPE_SOA)
+ continue;
+
+ if (!parent) {
+ parent = dns_resource_key_name(rr->key);
+ r = dns_name_parent(&parent);
+ if (r < 0)
+ return r;
+ if (r == 0) {
+ if (rr->key->type == DNS_TYPE_DS)
+ return true;
+
+ /* A CNAME/DNAME without a parent? That's sooo weird. */
+ log_debug("Transaction %" PRIu16 " claims CNAME/DNAME at root. Refusing.", t->id);
+ return -EBADMSG;
+ }
+ }
+
+ r = dns_name_equal(dns_resource_key_name(dt->key), parent);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ return t->answer_authenticated;
+ }
+
+ return true;
+ }
+
+ default: {
+ DnsTransaction *dt;
+ Iterator i;
+
+ /* Any other kind of RR (including DNSKEY/NSEC/NSEC3). Let's see if our SOA lookup was authenticated */
+
+ SET_FOREACH(dt, t->dnssec_transactions, i) {
+
+ if (dt->key->class != rr->key->class)
+ continue;
+ if (dt->key->type != DNS_TYPE_SOA)
+ continue;
+
+ r = dns_name_equal(dns_resource_key_name(dt->key), dns_resource_key_name(rr->key));
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ /* We found the transaction that was supposed to find
+ * the SOA RR for us. It was successful, but found no
+ * RR for us. This means we are not at a zone cut. In
+ * this case, we require authentication if the SOA
+ * lookup was authenticated too. */
+ return t->answer_authenticated;
+ }
+
+ return true;
+ }}
+}
+
+static int dns_transaction_in_private_tld(DnsTransaction *t, const DnsResourceKey *key) {
+ DnsTransaction *dt;
+ const char *tld;
+ Iterator i;
+ int r;
+
+ /* If DNSSEC downgrade mode is on, checks whether the
+ * specified RR is one level below a TLD we have proven not to
+ * exist. In such a case we assume that this is a private
+ * domain, and permit it.
+ *
+ * This detects cases like the Fritz!Box router networks. Each
+ * Fritz!Box router serves a private "fritz.box" zone, in the
+ * non-existing TLD "box". Requests for the "fritz.box" domain
+ * are served by the router itself, while requests for the
+ * "box" domain will result in NXDOMAIN.
+ *
+ * Note that this logic is unable to detect cases where a
+ * router serves a private DNS zone directly under
+ * non-existing TLD. In such a case we cannot detect whether
+ * the TLD is supposed to exist or not, as all requests we
+ * make for it will be answered by the router's zone, and not
+ * by the root zone. */
+
+ assert(t);
+
+ if (t->scope->dnssec_mode != DNSSEC_ALLOW_DOWNGRADE)
+ return false; /* In strict DNSSEC mode what doesn't exist, doesn't exist */
+
+ tld = dns_resource_key_name(key);
+ r = dns_name_parent(&tld);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return false; /* Already the root domain */
+
+ if (!dns_name_is_single_label(tld))
+ return false;
+
+ SET_FOREACH(dt, t->dnssec_transactions, i) {
+
+ if (dt->key->class != key->class)
+ continue;
+
+ r = dns_name_equal(dns_resource_key_name(dt->key), tld);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ /* We found an auxiliary lookup we did for the TLD. If
+ * that returned with NXDOMAIN, we know the TLD didn't
+ * exist, and hence this might be a private zone. */
+
+ return dt->answer_rcode == DNS_RCODE_NXDOMAIN;
+ }
+
+ return false;
+}
+
+static int dns_transaction_requires_nsec(DnsTransaction *t) {
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
+ DnsTransaction *dt;
+ const char *name;
+ uint16_t type = 0;
+ Iterator i;
+ int r;
+
+ assert(t);
+
+ /* Checks if we need to insist on NSEC/NSEC3 RRs for proving
+ * this negative reply */
+
+ if (t->scope->dnssec_mode == DNSSEC_NO)
+ return false;
+
+ if (dns_type_is_pseudo(t->key->type))
+ return -EINVAL;
+
+ r = dns_transaction_negative_trust_anchor_lookup(t, dns_resource_key_name(t->key));
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return false;
+
+ r = dns_transaction_in_private_tld(t, t->key);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ /* The lookup is from a TLD that is proven not to
+ * exist, and we are in downgrade mode, hence ignore
+ * that fact that we didn't get any NSEC RRs.*/
+
+ log_info("Detected a negative query %s in a private DNS zone, permitting unsigned response.",
+ dns_resource_key_to_string(t->key, key_str, sizeof key_str));
+ return false;
+ }
+
+ name = dns_resource_key_name(t->key);
+
+ if (t->key->type == DNS_TYPE_DS) {
+
+ /* We got a negative reply for this DS lookup? DS RRs are signed when their parent zone is signed,
+ * hence check the parent SOA in this case. */
+
+ r = dns_name_parent(&name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return true;
+
+ type = DNS_TYPE_SOA;
+
+ } else if (IN_SET(t->key->type, DNS_TYPE_SOA, DNS_TYPE_NS))
+ /* We got a negative reply for this SOA/NS lookup? If so, check if there's a DS RR for this */
+ type = DNS_TYPE_DS;
+ else
+ /* For all other negative replies, check for the SOA lookup */
+ type = DNS_TYPE_SOA;
+
+ /* For all other RRs we check the SOA on the same level to see
+ * if it's signed. */
+
+ SET_FOREACH(dt, t->dnssec_transactions, i) {
+
+ if (dt->key->class != t->key->class)
+ continue;
+ if (dt->key->type != type)
+ continue;
+
+ r = dns_name_equal(dns_resource_key_name(dt->key), name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ return dt->answer_authenticated;
+ }
+
+ /* If in doubt, require NSEC/NSEC3 */
+ return true;
+}
+
+static int dns_transaction_dnskey_authenticated(DnsTransaction *t, DnsResourceRecord *rr) {
+ DnsResourceRecord *rrsig;
+ bool found = false;
+ int r;
+
+ /* Checks whether any of the DNSKEYs used for the RRSIGs for
+ * the specified RRset is authenticated (i.e. has a matching
+ * DS RR). */
+
+ r = dns_transaction_negative_trust_anchor_lookup(t, dns_resource_key_name(rr->key));
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return false;
+
+ DNS_ANSWER_FOREACH(rrsig, t->answer) {
+ DnsTransaction *dt;
+ Iterator i;
+
+ r = dnssec_key_match_rrsig(rr->key, rrsig);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ SET_FOREACH(dt, t->dnssec_transactions, i) {
+
+ if (dt->key->class != rr->key->class)
+ continue;
+
+ if (dt->key->type == DNS_TYPE_DNSKEY) {
+
+ r = dns_name_equal(dns_resource_key_name(dt->key), rrsig->rrsig.signer);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ /* OK, we found an auxiliary DNSKEY
+ * lookup. If that lookup is
+ * authenticated, report this. */
+
+ if (dt->answer_authenticated)
+ return true;
+
+ found = true;
+
+ } else if (dt->key->type == DNS_TYPE_DS) {
+
+ r = dns_name_equal(dns_resource_key_name(dt->key), rrsig->rrsig.signer);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ /* OK, we found an auxiliary DS
+ * lookup. If that lookup is
+ * authenticated and non-zero, we
+ * won! */
+
+ if (!dt->answer_authenticated)
+ return false;
+
+ return dns_answer_match_key(dt->answer, dt->key, NULL);
+ }
+ }
+ }
+
+ return found ? false : -ENXIO;
+}
+
+static int dns_transaction_known_signed(DnsTransaction *t, DnsResourceRecord *rr) {
+ assert(t);
+ assert(rr);
+
+ /* We know that the root domain is signed, hence if it appears
+ * not to be signed, there's a problem with the DNS server */
+
+ return rr->key->class == DNS_CLASS_IN &&
+ dns_name_is_root(dns_resource_key_name(rr->key));
+}
+
+static int dns_transaction_check_revoked_trust_anchors(DnsTransaction *t) {
+ DnsResourceRecord *rr;
+ int r;
+
+ assert(t);
+
+ /* Maybe warn the user that we encountered a revoked DNSKEY
+ * for a key from our trust anchor. Note that we don't care
+ * whether the DNSKEY can be authenticated or not. It's
+ * sufficient if it is self-signed. */
+
+ DNS_ANSWER_FOREACH(rr, t->answer) {
+ r = dns_trust_anchor_check_revoked(&t->scope->manager->trust_anchor, rr, t->answer);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static int dns_transaction_invalidate_revoked_keys(DnsTransaction *t) {
+ bool changed;
+ int r;
+
+ assert(t);
+
+ /* Removes all DNSKEY/DS objects from t->validated_keys that
+ * our trust anchors database considers revoked. */
+
+ do {
+ DnsResourceRecord *rr;
+
+ changed = false;
+
+ DNS_ANSWER_FOREACH(rr, t->validated_keys) {
+ r = dns_trust_anchor_is_revoked(&t->scope->manager->trust_anchor, rr);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ r = dns_answer_remove_by_rr(&t->validated_keys, rr);
+ if (r < 0)
+ return r;
+
+ assert(r > 0);
+ changed = true;
+ break;
+ }
+ }
+ } while (changed);
+
+ return 0;
+}
+
+static int dns_transaction_copy_validated(DnsTransaction *t) {
+ DnsTransaction *dt;
+ Iterator i;
+ int r;
+
+ assert(t);
+
+ /* Copy all validated RRs from the auxiliary DNSSEC transactions into our set of validated RRs */
+
+ SET_FOREACH(dt, t->dnssec_transactions, i) {
+
+ if (DNS_TRANSACTION_IS_LIVE(dt->state))
+ continue;
+
+ if (!dt->answer_authenticated)
+ continue;
+
+ r = dns_answer_extend(&t->validated_keys, dt->answer);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+typedef enum {
+ DNSSEC_PHASE_DNSKEY, /* Phase #1, only validate DNSKEYs */
+ DNSSEC_PHASE_NSEC, /* Phase #2, only validate NSEC+NSEC3 */
+ DNSSEC_PHASE_ALL, /* Phase #3, validate everything else */
+} Phase;
+
+static int dnssec_validate_records(
+ DnsTransaction *t,
+ Phase phase,
+ bool *have_nsec,
+ DnsAnswer **validated) {
+
+ DnsResourceRecord *rr;
+ int r;
+
+ /* Returns negative on error, 0 if validation failed, 1 to restart validation, 2 when finished. */
+
+ DNS_ANSWER_FOREACH(rr, t->answer) {
+ DnsResourceRecord *rrsig = NULL;
+ DnssecResult result;
+
+ switch (rr->key->type) {
+ case DNS_TYPE_RRSIG:
+ continue;
+
+ case DNS_TYPE_DNSKEY:
+ /* We validate DNSKEYs only in the DNSKEY and ALL phases */
+ if (phase == DNSSEC_PHASE_NSEC)
+ continue;
+ break;
+
+ case DNS_TYPE_NSEC:
+ case DNS_TYPE_NSEC3:
+ *have_nsec = true;
+
+ /* We validate NSEC/NSEC3 only in the NSEC and ALL phases */
+ if (phase == DNSSEC_PHASE_DNSKEY)
+ continue;
+ break;
+
+ default:
+ /* We validate all other RRs only in the ALL phases */
+ if (phase != DNSSEC_PHASE_ALL)
+ continue;
+ }
+
+ r = dnssec_verify_rrset_search(t->answer, rr->key, t->validated_keys, USEC_INFINITY, &result, &rrsig);
+ if (r < 0)
+ return r;
+
+ log_debug("Looking at %s: %s", strna(dns_resource_record_to_string(rr)), dnssec_result_to_string(result));
+
+ if (result == DNSSEC_VALIDATED) {
+
+ if (rr->key->type == DNS_TYPE_DNSKEY) {
+ /* If we just validated a DNSKEY RRset, then let's add these keys to
+ * the set of validated keys for this transaction. */
+
+ r = dns_answer_copy_by_key(&t->validated_keys, t->answer, rr->key, DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+
+ /* Some of the DNSKEYs we just added might already have been revoked,
+ * remove them again in that case. */
+ r = dns_transaction_invalidate_revoked_keys(t);
+ if (r < 0)
+ return r;
+ }
+
+ /* Add the validated RRset to the new list of validated
+ * RRsets, and remove it from the unvalidated RRsets.
+ * We mark the RRset as authenticated and cacheable. */
+ r = dns_answer_move_by_key(validated, &t->answer, rr->key, DNS_ANSWER_AUTHENTICATED|DNS_ANSWER_CACHEABLE);
+ if (r < 0)
+ return r;
+
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_SECURE, rr->key);
+
+ /* Exit the loop, we dropped something from the answer, start from the beginning */
+ return 1;
+ }
+
+ /* If we haven't read all DNSKEYs yet a negative result of the validation is irrelevant, as
+ * there might be more DNSKEYs coming. Similar, if we haven't read all NSEC/NSEC3 RRs yet,
+ * we cannot do positive wildcard proofs yet, as those require the NSEC/NSEC3 RRs. */
+ if (phase != DNSSEC_PHASE_ALL)
+ continue;
+
+ if (result == DNSSEC_VALIDATED_WILDCARD) {
+ bool authenticated = false;
+ const char *source;
+
+ /* This RRset validated, but as a wildcard. This means we need
+ * to prove via NSEC/NSEC3 that no matching non-wildcard RR exists.*/
+
+ /* First step, determine the source of synthesis */
+ r = dns_resource_record_source(rrsig, &source);
+ if (r < 0)
+ return r;
+
+ r = dnssec_test_positive_wildcard(*validated,
+ dns_resource_key_name(rr->key),
+ source,
+ rrsig->rrsig.signer,
+ &authenticated);
+
+ /* Unless the NSEC proof showed that the key really doesn't exist something is off. */
+ if (r == 0)
+ result = DNSSEC_INVALID;
+ else {
+ r = dns_answer_move_by_key(validated, &t->answer, rr->key,
+ authenticated ? (DNS_ANSWER_AUTHENTICATED|DNS_ANSWER_CACHEABLE) : 0);
+ if (r < 0)
+ return r;
+
+ manager_dnssec_verdict(t->scope->manager, authenticated ? DNSSEC_SECURE : DNSSEC_INSECURE, rr->key);
+
+ /* Exit the loop, we dropped something from the answer, start from the beginning */
+ return 1;
+ }
+ }
+
+ if (result == DNSSEC_NO_SIGNATURE) {
+ r = dns_transaction_requires_rrsig(t, rr);
+ if (r < 0)
+ return r;
+ if (r == 0) {
+ /* Data does not require signing. In that case, just copy it over,
+ * but remember that this is by no means authenticated.*/
+ r = dns_answer_move_by_key(validated, &t->answer, rr->key, 0);
+ if (r < 0)
+ return r;
+
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_INSECURE, rr->key);
+ return 1;
+ }
+
+ r = dns_transaction_known_signed(t, rr);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ /* This is an RR we know has to be signed. If it isn't this means
+ * the server is not attaching RRSIGs, hence complain. */
+
+ dns_server_packet_rrsig_missing(t->server, t->current_feature_level);
+
+ if (t->scope->dnssec_mode == DNSSEC_ALLOW_DOWNGRADE) {
+
+ /* Downgrading is OK? If so, just consider the information unsigned */
+
+ r = dns_answer_move_by_key(validated, &t->answer, rr->key, 0);
+ if (r < 0)
+ return r;
+
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_INSECURE, rr->key);
+ return 1;
+ }
+
+ /* Otherwise, fail */
+ t->answer_dnssec_result = DNSSEC_INCOMPATIBLE_SERVER;
+ return 0;
+ }
+
+ r = dns_transaction_in_private_tld(t, rr->key);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ char s[DNS_RESOURCE_KEY_STRING_MAX];
+
+ /* The data is from a TLD that is proven not to exist, and we are in downgrade
+ * mode, hence ignore the fact that this was not signed. */
+
+ log_info("Detected RRset %s is in a private DNS zone, permitting unsigned RRs.",
+ dns_resource_key_to_string(rr->key, s, sizeof s));
+
+ r = dns_answer_move_by_key(validated, &t->answer, rr->key, 0);
+ if (r < 0)
+ return r;
+
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_INSECURE, rr->key);
+ return 1;
+ }
+ }
+
+ if (IN_SET(result,
+ DNSSEC_MISSING_KEY,
+ DNSSEC_SIGNATURE_EXPIRED,
+ DNSSEC_UNSUPPORTED_ALGORITHM)) {
+
+ r = dns_transaction_dnskey_authenticated(t, rr);
+ if (r < 0 && r != -ENXIO)
+ return r;
+ if (r == 0) {
+ /* The DNSKEY transaction was not authenticated, this means there's
+ * no DS for this, which means it's OK if no keys are found for this signature. */
+
+ r = dns_answer_move_by_key(validated, &t->answer, rr->key, 0);
+ if (r < 0)
+ return r;
+
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_INSECURE, rr->key);
+ return 1;
+ }
+ }
+
+ r = dns_transaction_is_primary_response(t, rr);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ /* Look for a matching DNAME for this CNAME */
+ r = dns_answer_has_dname_for_cname(t->answer, rr);
+ if (r < 0)
+ return r;
+ if (r == 0) {
+ /* Also look among the stuff we already validated */
+ r = dns_answer_has_dname_for_cname(*validated, rr);
+ if (r < 0)
+ return r;
+ }
+
+ if (r == 0) {
+ if (IN_SET(result,
+ DNSSEC_INVALID,
+ DNSSEC_SIGNATURE_EXPIRED,
+ DNSSEC_NO_SIGNATURE))
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_BOGUS, rr->key);
+ else /* DNSSEC_MISSING_KEY or DNSSEC_UNSUPPORTED_ALGORITHM */
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_INDETERMINATE, rr->key);
+
+ /* This is a primary response to our question, and it failed validation.
+ * That's fatal. */
+ t->answer_dnssec_result = result;
+ return 0;
+ }
+
+ /* This is a primary response, but we do have a DNAME RR
+ * in the RR that can replay this CNAME, hence rely on
+ * that, and we can remove the CNAME in favour of it. */
+ }
+
+ /* This is just some auxiliary data. Just remove the RRset and continue. */
+ r = dns_answer_remove_by_key(&t->answer, rr->key);
+ if (r < 0)
+ return r;
+
+ /* We dropped something from the answer, start from the beginning. */
+ return 1;
+ }
+
+ return 2; /* Finito. */
+}
+
+int dns_transaction_validate_dnssec(DnsTransaction *t) {
+ _cleanup_(dns_answer_unrefp) DnsAnswer *validated = NULL;
+ Phase phase;
+ DnsAnswerFlags flags;
+ int r;
+ char key_str[DNS_RESOURCE_KEY_STRING_MAX];
+
+ assert(t);
+
+ /* We have now collected all DS and DNSKEY RRs in
+ * t->validated_keys, let's see which RRs we can now
+ * authenticate with that. */
+
+ if (t->scope->dnssec_mode == DNSSEC_NO)
+ return 0;
+
+ /* Already validated */
+ if (t->answer_dnssec_result != _DNSSEC_RESULT_INVALID)
+ return 0;
+
+ /* Our own stuff needs no validation */
+ if (IN_SET(t->answer_source, DNS_TRANSACTION_ZONE, DNS_TRANSACTION_TRUST_ANCHOR)) {
+ t->answer_dnssec_result = DNSSEC_VALIDATED;
+ t->answer_authenticated = true;
+ return 0;
+ }
+
+ /* Cached stuff is not affected by validation. */
+ if (t->answer_source != DNS_TRANSACTION_NETWORK)
+ return 0;
+
+ if (!dns_transaction_dnssec_supported_full(t)) {
+ /* The server does not support DNSSEC, or doesn't augment responses with RRSIGs. */
+ t->answer_dnssec_result = DNSSEC_INCOMPATIBLE_SERVER;
+ log_debug("Not validating response for %" PRIu16 ", used server feature level does not support DNSSEC.", t->id);
+ return 0;
+ }
+
+ log_debug("Validating response from transaction %" PRIu16 " (%s).",
+ t->id,
+ dns_resource_key_to_string(t->key, key_str, sizeof key_str));
+
+ /* First, see if this response contains any revoked trust
+ * anchors we care about */
+ r = dns_transaction_check_revoked_trust_anchors(t);
+ if (r < 0)
+ return r;
+
+ /* Third, copy all RRs we acquired successfully from auxiliary RRs over. */
+ r = dns_transaction_copy_validated(t);
+ if (r < 0)
+ return r;
+
+ /* Second, see if there are DNSKEYs we already know a
+ * validated DS for. */
+ r = dns_transaction_validate_dnskey_by_ds(t);
+ if (r < 0)
+ return r;
+
+ /* Fourth, remove all DNSKEY and DS RRs again that our trust
+ * anchor says are revoked. After all we might have marked
+ * some keys revoked above, but they might still be lingering
+ * in our validated_keys list. */
+ r = dns_transaction_invalidate_revoked_keys(t);
+ if (r < 0)
+ return r;
+
+ phase = DNSSEC_PHASE_DNSKEY;
+ for (;;) {
+ bool have_nsec = false;
+
+ r = dnssec_validate_records(t, phase, &have_nsec, &validated);
+ if (r <= 0)
+ return r;
+
+ /* Try again as long as we managed to achieve something */
+ if (r == 1)
+ continue;
+
+ if (phase == DNSSEC_PHASE_DNSKEY && have_nsec) {
+ /* OK, we processed all DNSKEYs, and there are NSEC/NSEC3 RRs, look at those now. */
+ phase = DNSSEC_PHASE_NSEC;
+ continue;
+ }
+
+ if (phase != DNSSEC_PHASE_ALL) {
+ /* OK, we processed all DNSKEYs and NSEC/NSEC3 RRs, look at all the rest now.
+ * Note that in this third phase we start to remove RRs we couldn't validate. */
+ phase = DNSSEC_PHASE_ALL;
+ continue;
+ }
+
+ /* We're done */
+ break;
+ }
+
+ dns_answer_unref(t->answer);
+ t->answer = validated;
+ validated = NULL;
+
+ /* At this point the answer only contains validated
+ * RRsets. Now, let's see if it actually answers the question
+ * we asked. If so, great! If it doesn't, then see if
+ * NSEC/NSEC3 can prove this. */
+ r = dns_transaction_has_positive_answer(t, &flags);
+ if (r > 0) {
+ /* Yes, it answers the question! */
+
+ if (flags & DNS_ANSWER_AUTHENTICATED) {
+ /* The answer is fully authenticated, yay. */
+ t->answer_dnssec_result = DNSSEC_VALIDATED;
+ t->answer_rcode = DNS_RCODE_SUCCESS;
+ t->answer_authenticated = true;
+ } else {
+ /* The answer is not fully authenticated. */
+ t->answer_dnssec_result = DNSSEC_UNSIGNED;
+ t->answer_authenticated = false;
+ }
+
+ } else if (r == 0) {
+ DnssecNsecResult nr;
+ bool authenticated = false;
+
+ /* Bummer! Let's check NSEC/NSEC3 */
+ r = dnssec_nsec_test(t->answer, t->key, &nr, &authenticated, &t->answer_nsec_ttl);
+ if (r < 0)
+ return r;
+
+ switch (nr) {
+
+ case DNSSEC_NSEC_NXDOMAIN:
+ /* NSEC proves the domain doesn't exist. Very good. */
+ log_debug("Proved NXDOMAIN via NSEC/NSEC3 for transaction %u (%s)", t->id, key_str);
+ t->answer_dnssec_result = DNSSEC_VALIDATED;
+ t->answer_rcode = DNS_RCODE_NXDOMAIN;
+ t->answer_authenticated = authenticated;
+
+ manager_dnssec_verdict(t->scope->manager, authenticated ? DNSSEC_SECURE : DNSSEC_INSECURE, t->key);
+ break;
+
+ case DNSSEC_NSEC_NODATA:
+ /* NSEC proves that there's no data here, very good. */
+ log_debug("Proved NODATA via NSEC/NSEC3 for transaction %u (%s)", t->id, key_str);
+ t->answer_dnssec_result = DNSSEC_VALIDATED;
+ t->answer_rcode = DNS_RCODE_SUCCESS;
+ t->answer_authenticated = authenticated;
+
+ manager_dnssec_verdict(t->scope->manager, authenticated ? DNSSEC_SECURE : DNSSEC_INSECURE, t->key);
+ break;
+
+ case DNSSEC_NSEC_OPTOUT:
+ /* NSEC3 says the data might not be signed */
+ log_debug("Data is NSEC3 opt-out via NSEC/NSEC3 for transaction %u (%s)", t->id, key_str);
+ t->answer_dnssec_result = DNSSEC_UNSIGNED;
+ t->answer_authenticated = false;
+
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_INSECURE, t->key);
+ break;
+
+ case DNSSEC_NSEC_NO_RR:
+ /* No NSEC data? Bummer! */
+
+ r = dns_transaction_requires_nsec(t);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ t->answer_dnssec_result = DNSSEC_NO_SIGNATURE;
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_BOGUS, t->key);
+ } else {
+ t->answer_dnssec_result = DNSSEC_UNSIGNED;
+ t->answer_authenticated = false;
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_INSECURE, t->key);
+ }
+
+ break;
+
+ case DNSSEC_NSEC_UNSUPPORTED_ALGORITHM:
+ /* We don't know the NSEC3 algorithm used? */
+ t->answer_dnssec_result = DNSSEC_UNSUPPORTED_ALGORITHM;
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_INDETERMINATE, t->key);
+ break;
+
+ case DNSSEC_NSEC_FOUND:
+ case DNSSEC_NSEC_CNAME:
+ /* NSEC says it needs to be there, but we couldn't find it? Bummer! */
+ t->answer_dnssec_result = DNSSEC_NSEC_MISMATCH;
+ manager_dnssec_verdict(t->scope->manager, DNSSEC_BOGUS, t->key);
+ break;
+
+ default:
+ assert_not_reached("Unexpected NSEC result.");
+ }
+ }
+
+ return 1;
+}
+
+static const char* const dns_transaction_state_table[_DNS_TRANSACTION_STATE_MAX] = {
+ [DNS_TRANSACTION_NULL] = "null",
+ [DNS_TRANSACTION_PENDING] = "pending",
+ [DNS_TRANSACTION_VALIDATING] = "validating",
+ [DNS_TRANSACTION_RCODE_FAILURE] = "rcode-failure",
+ [DNS_TRANSACTION_SUCCESS] = "success",
+ [DNS_TRANSACTION_NO_SERVERS] = "no-servers",
+ [DNS_TRANSACTION_TIMEOUT] = "timeout",
+ [DNS_TRANSACTION_ATTEMPTS_MAX_REACHED] = "attempts-max-reached",
+ [DNS_TRANSACTION_INVALID_REPLY] = "invalid-reply",
+ [DNS_TRANSACTION_ERRNO] = "errno",
+ [DNS_TRANSACTION_ABORTED] = "aborted",
+ [DNS_TRANSACTION_DNSSEC_FAILED] = "dnssec-failed",
+ [DNS_TRANSACTION_NO_TRUST_ANCHOR] = "no-trust-anchor",
+ [DNS_TRANSACTION_RR_TYPE_UNSUPPORTED] = "rr-type-unsupported",
+ [DNS_TRANSACTION_NETWORK_DOWN] = "network-down",
+ [DNS_TRANSACTION_NOT_FOUND] = "not-found",
+};
+DEFINE_STRING_TABLE_LOOKUP(dns_transaction_state, DnsTransactionState);
+
+static const char* const dns_transaction_source_table[_DNS_TRANSACTION_SOURCE_MAX] = {
+ [DNS_TRANSACTION_NETWORK] = "network",
+ [DNS_TRANSACTION_CACHE] = "cache",
+ [DNS_TRANSACTION_ZONE] = "zone",
+ [DNS_TRANSACTION_TRUST_ANCHOR] = "trust-anchor",
+};
+DEFINE_STRING_TABLE_LOOKUP(dns_transaction_source, DnsTransactionSource);
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-transaction.h b/src/grp-resolve/systemd-resolved/resolved-dns-transaction.h
new file mode 100644
index 0000000000..cdc598fa9c
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-transaction.h
@@ -0,0 +1,180 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+typedef struct DnsTransaction DnsTransaction;
+typedef enum DnsTransactionState DnsTransactionState;
+typedef enum DnsTransactionSource DnsTransactionSource;
+
+enum DnsTransactionState {
+ DNS_TRANSACTION_NULL,
+ DNS_TRANSACTION_PENDING,
+ DNS_TRANSACTION_VALIDATING,
+ DNS_TRANSACTION_RCODE_FAILURE,
+ DNS_TRANSACTION_SUCCESS,
+ DNS_TRANSACTION_NO_SERVERS,
+ DNS_TRANSACTION_TIMEOUT,
+ DNS_TRANSACTION_ATTEMPTS_MAX_REACHED,
+ DNS_TRANSACTION_INVALID_REPLY,
+ DNS_TRANSACTION_ERRNO,
+ DNS_TRANSACTION_ABORTED,
+ DNS_TRANSACTION_DNSSEC_FAILED,
+ DNS_TRANSACTION_NO_TRUST_ANCHOR,
+ DNS_TRANSACTION_RR_TYPE_UNSUPPORTED,
+ DNS_TRANSACTION_NETWORK_DOWN,
+ DNS_TRANSACTION_NOT_FOUND, /* like NXDOMAIN, but when LLMNR/TCP connections fail */
+ _DNS_TRANSACTION_STATE_MAX,
+ _DNS_TRANSACTION_STATE_INVALID = -1
+};
+
+#define DNS_TRANSACTION_IS_LIVE(state) IN_SET((state), DNS_TRANSACTION_NULL, DNS_TRANSACTION_PENDING, DNS_TRANSACTION_VALIDATING)
+
+enum DnsTransactionSource {
+ DNS_TRANSACTION_NETWORK,
+ DNS_TRANSACTION_CACHE,
+ DNS_TRANSACTION_ZONE,
+ DNS_TRANSACTION_TRUST_ANCHOR,
+ _DNS_TRANSACTION_SOURCE_MAX,
+ _DNS_TRANSACTION_SOURCE_INVALID = -1
+};
+
+#include "basic-dns/resolved-dns-answer.h"
+#include "basic-dns/resolved-dns-packet.h"
+#include "basic-dns/resolved-dns-question.h"
+
+#include "resolved-dns-scope.h"
+
+struct DnsTransaction {
+ DnsScope *scope;
+
+ DnsResourceKey *key;
+
+ DnsTransactionState state;
+
+ uint16_t id;
+
+ bool tried_stream:1;
+
+ bool initial_jitter_scheduled:1;
+ bool initial_jitter_elapsed:1;
+
+ bool clamp_ttl:1;
+
+ DnsPacket *sent, *received;
+
+ DnsAnswer *answer;
+ int answer_rcode;
+ DnssecResult answer_dnssec_result;
+ DnsTransactionSource answer_source;
+ uint32_t answer_nsec_ttl;
+ int answer_errno; /* if state is DNS_TRANSACTION_ERRNO */
+
+ /* Indicates whether the primary answer is authenticated,
+ * i.e. whether the RRs from answer which directly match the
+ * question are authenticated, or, if there are none, whether
+ * the NODATA or NXDOMAIN case is. It says nothing about
+ * additional RRs listed in the answer, however they have
+ * their own DNS_ANSWER_AUTHORIZED FLAGS. Note that this bit
+ * is defined different than the AD bit in DNS packets, as
+ * that covers more than just the actual primary answer. */
+ bool answer_authenticated;
+
+ /* Contains DNSKEY, DS, SOA RRs we already verified and need
+ * to authenticate this reply */
+ DnsAnswer *validated_keys;
+
+ usec_t start_usec;
+ usec_t next_attempt_after;
+ sd_event_source *timeout_event_source;
+ unsigned n_attempts;
+
+ /* UDP connection logic, if we need it */
+ int dns_udp_fd;
+ sd_event_source *dns_udp_event_source;
+
+ /* TCP connection logic, if we need it */
+ DnsStream *stream;
+
+ /* The active server */
+ DnsServer *server;
+
+ /* The features of the DNS server at time of transaction start */
+ DnsServerFeatureLevel current_feature_level;
+
+ /* If we got SERVFAIL back, we retry the lookup, using a lower feature level than we used before. */
+ DnsServerFeatureLevel clamp_feature_level;
+
+ /* Query candidates this transaction is referenced by and that
+ * shall be notified about this specific transaction
+ * completing. */
+ Set *notify_query_candidates, *notify_query_candidates_done;
+
+ /* Zone items this transaction is referenced by and that shall
+ * be notified about completion. */
+ Set *notify_zone_items, *notify_zone_items_done;
+
+ /* Other transactions that this transactions is referenced by
+ * and that shall be notified about completion. This is used
+ * when transactions want to validate their RRsets, but need
+ * another DNSKEY or DS RR to do so. */
+ Set *notify_transactions, *notify_transactions_done;
+
+ /* The opposite direction: the transactions this transaction
+ * created in order to request DNSKEY or DS RRs. */
+ Set *dnssec_transactions;
+
+ unsigned block_gc;
+
+ LIST_FIELDS(DnsTransaction, transactions_by_scope);
+};
+
+int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsResourceKey *key);
+DnsTransaction* dns_transaction_free(DnsTransaction *t);
+
+bool dns_transaction_gc(DnsTransaction *t);
+int dns_transaction_go(DnsTransaction *t);
+
+void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p);
+void dns_transaction_complete(DnsTransaction *t, DnsTransactionState state);
+
+void dns_transaction_notify(DnsTransaction *t, DnsTransaction *source);
+int dns_transaction_validate_dnssec(DnsTransaction *t);
+int dns_transaction_request_dnssec_keys(DnsTransaction *t);
+
+const char* dns_transaction_state_to_string(DnsTransactionState p) _const_;
+DnsTransactionState dns_transaction_state_from_string(const char *s) _pure_;
+
+const char* dns_transaction_source_to_string(DnsTransactionSource p) _const_;
+DnsTransactionSource dns_transaction_source_from_string(const char *s) _pure_;
+
+/* LLMNR Jitter interval, see RFC 4795 Section 7 */
+#define LLMNR_JITTER_INTERVAL_USEC (100 * USEC_PER_MSEC)
+
+/* mDNS Jitter interval, see RFC 6762 Section 5.2 */
+#define MDNS_JITTER_MIN_USEC (20 * USEC_PER_MSEC)
+#define MDNS_JITTER_RANGE_USEC (100 * USEC_PER_MSEC)
+
+/* Maximum attempts to send DNS requests, across all DNS servers */
+#define DNS_TRANSACTION_ATTEMPTS_MAX 16
+
+/* Maximum attempts to send LLMNR requests, see RFC 4795 Section 2.7 */
+#define LLMNR_TRANSACTION_ATTEMPTS_MAX 3
+
+#define TRANSACTION_ATTEMPTS_MAX(p) ((p) == DNS_PROTOCOL_LLMNR ? LLMNR_TRANSACTION_ATTEMPTS_MAX : DNS_TRANSACTION_ATTEMPTS_MAX)
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-trust-anchor.c b/src/grp-resolve/systemd-resolved/resolved-dns-trust-anchor.c
new file mode 100644
index 0000000000..53cd9d8f55
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-trust-anchor.c
@@ -0,0 +1,744 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2015 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <systemd/sd-messages.h>
+
+#include "basic-dns/resolved-dns-dnssec.h"
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/conf-files.h"
+#include "systemd-basic/def.h"
+#include "systemd-basic/fd-util.h"
+#include "systemd-basic/fileio.h"
+#include "systemd-basic/hexdecoct.h"
+#include "systemd-basic/parse-util.h"
+#include "systemd-basic/set.h"
+#include "systemd-basic/string-util.h"
+#include "systemd-basic/strv.h"
+#include "systemd-shared/dns-domain.h"
+
+#include "resolved-dns-trust-anchor.h"
+
+static const char trust_anchor_dirs[] = CONF_PATHS_NULSTR("dnssec-trust-anchors.d");
+
+/* The DS RR from https://data.iana.org/root-anchors/root-anchors.xml, retrieved December 2015 */
+static const uint8_t root_digest[] =
+ { 0x49, 0xAA, 0xC1, 0x1D, 0x7B, 0x6F, 0x64, 0x46, 0x70, 0x2E, 0x54, 0xA1, 0x60, 0x73, 0x71, 0x60,
+ 0x7A, 0x1A, 0x41, 0x85, 0x52, 0x00, 0xFD, 0x2C, 0xE1, 0xCD, 0xDE, 0x32, 0xF2, 0x4E, 0x8F, 0xB5 };
+
+static bool dns_trust_anchor_knows_domain_positive(DnsTrustAnchor *d, const char *name) {
+ assert(d);
+
+ /* Returns true if there's an entry for the specified domain
+ * name in our trust anchor */
+
+ return
+ hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DNSKEY, name)) ||
+ hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DS, name));
+}
+
+static int dns_trust_anchor_add_builtin_positive(DnsTrustAnchor *d) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+ _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
+ int r;
+
+ assert(d);
+
+ r = hashmap_ensure_allocated(&d->positive_by_key, &dns_resource_key_hash_ops);
+ if (r < 0)
+ return r;
+
+ /* Only add the built-in trust anchor if there's neither a DS
+ * nor a DNSKEY defined for the root domain. That way users
+ * have an easy way to override the root domain DS/DNSKEY
+ * data. */
+ if (dns_trust_anchor_knows_domain_positive(d, "."))
+ return 0;
+
+ /* Add the RR from https://data.iana.org/root-anchors/root-anchors.xml */
+ rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DS, "");
+ if (!rr)
+ return -ENOMEM;
+
+ rr->ds.key_tag = 19036;
+ rr->ds.algorithm = DNSSEC_ALGORITHM_RSASHA256;
+ rr->ds.digest_type = DNSSEC_DIGEST_SHA256;
+ rr->ds.digest_size = sizeof(root_digest);
+ rr->ds.digest = memdup(root_digest, rr->ds.digest_size);
+ if (!rr->ds.digest)
+ return -ENOMEM;
+
+ answer = dns_answer_new(1);
+ if (!answer)
+ return -ENOMEM;
+
+ r = dns_answer_add(answer, rr, 0, DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+
+ r = hashmap_put(d->positive_by_key, rr->key, answer);
+ if (r < 0)
+ return r;
+
+ answer = NULL;
+ return 0;
+}
+
+static int dns_trust_anchor_add_builtin_negative(DnsTrustAnchor *d) {
+
+ static const char private_domains[] =
+ /* RFC 6761 says that .test is a special domain for
+ * testing and not to be installed in the root zone */
+ "test\0"
+
+ /* RFC 6761 says that these reverse IP lookup ranges
+ * are for private addresses, and hence should not
+ * show up in the root zone */
+ "10.in-addr.arpa\0"
+ "16.172.in-addr.arpa\0"
+ "17.172.in-addr.arpa\0"
+ "18.172.in-addr.arpa\0"
+ "19.172.in-addr.arpa\0"
+ "20.172.in-addr.arpa\0"
+ "21.172.in-addr.arpa\0"
+ "22.172.in-addr.arpa\0"
+ "23.172.in-addr.arpa\0"
+ "24.172.in-addr.arpa\0"
+ "25.172.in-addr.arpa\0"
+ "26.172.in-addr.arpa\0"
+ "27.172.in-addr.arpa\0"
+ "28.172.in-addr.arpa\0"
+ "29.172.in-addr.arpa\0"
+ "30.172.in-addr.arpa\0"
+ "31.172.in-addr.arpa\0"
+ "168.192.in-addr.arpa\0"
+
+ /* RFC 6762 reserves the .local domain for Multicast
+ * DNS, it hence cannot appear in the root zone. (Note
+ * that we by default do not route .local traffic to
+ * DNS anyway, except when a configured search domain
+ * suggests so.) */
+ "local\0"
+
+ /* These two are well known, popular private zone
+ * TLDs, that are blocked from delegation, according
+ * to:
+ * http://icannwiki.com/Name_Collision#NGPC_Resolution
+ *
+ * There's also ongoing work on making this official
+ * in an RRC:
+ * https://www.ietf.org/archive/id/draft-chapin-additional-reserved-tlds-02.txt */
+ "home\0"
+ "corp\0"
+
+ /* The following four TLDs are suggested for private
+ * zones in RFC 6762, Appendix G, and are hence very
+ * unlikely to be made official TLDs any day soon */
+ "lan\0"
+ "intranet\0"
+ "internal\0"
+ "private\0";
+
+ const char *name;
+ int r;
+
+ assert(d);
+
+ /* Only add the built-in trust anchor if there's no negative
+ * trust anchor defined at all. This enables easy overriding
+ * of negative trust anchors. */
+
+ if (set_size(d->negative_by_name) > 0)
+ return 0;
+
+ r = set_ensure_allocated(&d->negative_by_name, &dns_name_hash_ops);
+ if (r < 0)
+ return r;
+
+ /* We add a couple of domains as default negative trust
+ * anchors, where it's very unlikely they will be installed in
+ * the root zone. If they exist they must be private, and thus
+ * unsigned. */
+
+ NULSTR_FOREACH(name, private_domains) {
+
+ if (dns_trust_anchor_knows_domain_positive(d, name))
+ continue;
+
+ r = set_put_strdup(d->negative_by_name, name);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static int dns_trust_anchor_load_positive(DnsTrustAnchor *d, const char *path, unsigned line, const char *s) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+ _cleanup_free_ char *domain = NULL, *class = NULL, *type = NULL;
+ _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
+ DnsAnswer *old_answer = NULL;
+ const char *p = s;
+ int r;
+
+ assert(d);
+ assert(line);
+
+ r = extract_first_word(&p, &domain, NULL, EXTRACT_QUOTES);
+ if (r < 0)
+ return log_warning_errno(r, "Unable to parse domain in line %s:%u: %m", path, line);
+
+ if (!dns_name_is_valid(domain)) {
+ log_warning("Domain name %s is invalid, at line %s:%u, ignoring line.", domain, path, line);
+ return -EINVAL;
+ }
+
+ r = extract_many_words(&p, NULL, 0, &class, &type, NULL);
+ if (r < 0)
+ return log_warning_errno(r, "Unable to parse class and type in line %s:%u: %m", path, line);
+ if (r != 2) {
+ log_warning("Missing class or type in line %s:%u", path, line);
+ return -EINVAL;
+ }
+
+ if (!strcaseeq(class, "IN")) {
+ log_warning("RR class %s is not supported, ignoring line %s:%u.", class, path, line);
+ return -EINVAL;
+ }
+
+ if (strcaseeq(type, "DS")) {
+ _cleanup_free_ char *key_tag = NULL, *algorithm = NULL, *digest_type = NULL, *digest = NULL;
+ _cleanup_free_ void *dd = NULL;
+ uint16_t kt;
+ int a, dt;
+ size_t l;
+
+ r = extract_many_words(&p, NULL, 0, &key_tag, &algorithm, &digest_type, &digest, NULL);
+ if (r < 0) {
+ log_warning_errno(r, "Failed to parse DS parameters on line %s:%u: %m", path, line);
+ return -EINVAL;
+ }
+ if (r != 4) {
+ log_warning("Missing DS parameters on line %s:%u", path, line);
+ return -EINVAL;
+ }
+
+ r = safe_atou16(key_tag, &kt);
+ if (r < 0)
+ return log_warning_errno(r, "Failed to parse DS key tag %s on line %s:%u: %m", key_tag, path, line);
+
+ a = dnssec_algorithm_from_string(algorithm);
+ if (a < 0) {
+ log_warning("Failed to parse DS algorithm %s on line %s:%u", algorithm, path, line);
+ return -EINVAL;
+ }
+
+ dt = dnssec_digest_from_string(digest_type);
+ if (dt < 0) {
+ log_warning("Failed to parse DS digest type %s on line %s:%u", digest_type, path, line);
+ return -EINVAL;
+ }
+
+ r = unhexmem(digest, strlen(digest), &dd, &l);
+ if (r < 0) {
+ log_warning("Failed to parse DS digest %s on line %s:%u", digest, path, line);
+ return -EINVAL;
+ }
+
+ rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DS, domain);
+ if (!rr)
+ return log_oom();
+
+ rr->ds.key_tag = kt;
+ rr->ds.algorithm = a;
+ rr->ds.digest_type = dt;
+ rr->ds.digest_size = l;
+ rr->ds.digest = dd;
+ dd = NULL;
+
+ } else if (strcaseeq(type, "DNSKEY")) {
+ _cleanup_free_ char *flags = NULL, *protocol = NULL, *algorithm = NULL, *key = NULL;
+ _cleanup_free_ void *k = NULL;
+ uint16_t f;
+ size_t l;
+ int a;
+
+ r = extract_many_words(&p, NULL, 0, &flags, &protocol, &algorithm, &key, NULL);
+ if (r < 0)
+ return log_warning_errno(r, "Failed to parse DNSKEY parameters on line %s:%u: %m", path, line);
+ if (r != 4) {
+ log_warning("Missing DNSKEY parameters on line %s:%u", path, line);
+ return -EINVAL;
+ }
+
+ if (!streq(protocol, "3")) {
+ log_warning("DNSKEY Protocol is not 3 on line %s:%u", path, line);
+ return -EINVAL;
+ }
+
+ r = safe_atou16(flags, &f);
+ if (r < 0)
+ return log_warning_errno(r, "Failed to parse DNSKEY flags field %s on line %s:%u", flags, path, line);
+ if ((f & DNSKEY_FLAG_ZONE_KEY) == 0) {
+ log_warning("DNSKEY lacks zone key bit set on line %s:%u", path, line);
+ return -EINVAL;
+ }
+ if ((f & DNSKEY_FLAG_REVOKE)) {
+ log_warning("DNSKEY is already revoked on line %s:%u", path, line);
+ return -EINVAL;
+ }
+
+ a = dnssec_algorithm_from_string(algorithm);
+ if (a < 0) {
+ log_warning("Failed to parse DNSKEY algorithm %s on line %s:%u", algorithm, path, line);
+ return -EINVAL;
+ }
+
+ r = unbase64mem(key, strlen(key), &k, &l);
+ if (r < 0)
+ return log_warning_errno(r, "Failed to parse DNSKEY key data %s on line %s:%u", key, path, line);
+
+ rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DNSKEY, domain);
+ if (!rr)
+ return log_oom();
+
+ rr->dnskey.flags = f;
+ rr->dnskey.protocol = 3;
+ rr->dnskey.algorithm = a;
+ rr->dnskey.key_size = l;
+ rr->dnskey.key = k;
+ k = NULL;
+
+ } else {
+ log_warning("RR type %s is not supported, ignoring line %s:%u.", type, path, line);
+ return -EINVAL;
+ }
+
+ if (!isempty(p)) {
+ log_warning("Trailing garbage on line %s:%u, ignoring line.", path, line);
+ return -EINVAL;
+ }
+
+ r = hashmap_ensure_allocated(&d->positive_by_key, &dns_resource_key_hash_ops);
+ if (r < 0)
+ return log_oom();
+
+ old_answer = hashmap_get(d->positive_by_key, rr->key);
+ answer = dns_answer_ref(old_answer);
+
+ r = dns_answer_add_extend(&answer, rr, 0, DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return log_error_errno(r, "Failed to add trust anchor RR: %m");
+
+ r = hashmap_replace(d->positive_by_key, rr->key, answer);
+ if (r < 0)
+ return log_error_errno(r, "Failed to add answer to trust anchor: %m");
+
+ old_answer = dns_answer_unref(old_answer);
+ answer = NULL;
+
+ return 0;
+}
+
+static int dns_trust_anchor_load_negative(DnsTrustAnchor *d, const char *path, unsigned line, const char *s) {
+ _cleanup_free_ char *domain = NULL;
+ const char *p = s;
+ int r;
+
+ assert(d);
+ assert(line);
+
+ r = extract_first_word(&p, &domain, NULL, EXTRACT_QUOTES);
+ if (r < 0)
+ return log_warning_errno(r, "Unable to parse line %s:%u: %m", path, line);
+
+ if (!dns_name_is_valid(domain)) {
+ log_warning("Domain name %s is invalid, at line %s:%u, ignoring line.", domain, path, line);
+ return -EINVAL;
+ }
+
+ if (!isempty(p)) {
+ log_warning("Trailing garbage at line %s:%u, ignoring line.", path, line);
+ return -EINVAL;
+ }
+
+ r = set_ensure_allocated(&d->negative_by_name, &dns_name_hash_ops);
+ if (r < 0)
+ return log_oom();
+
+ r = set_put(d->negative_by_name, domain);
+ if (r < 0)
+ return log_oom();
+ if (r > 0)
+ domain = NULL;
+
+ return 0;
+}
+
+static int dns_trust_anchor_load_files(
+ DnsTrustAnchor *d,
+ const char *suffix,
+ int (*loader)(DnsTrustAnchor *d, const char *path, unsigned n, const char *line)) {
+
+ _cleanup_strv_free_ char **files = NULL;
+ char **f;
+ int r;
+
+ assert(d);
+ assert(suffix);
+ assert(loader);
+
+ r = conf_files_list_nulstr(&files, suffix, NULL, trust_anchor_dirs);
+ if (r < 0)
+ return log_error_errno(r, "Failed to enumerate %s trust anchor files: %m", suffix);
+
+ STRV_FOREACH(f, files) {
+ _cleanup_fclose_ FILE *g = NULL;
+ char line[LINE_MAX];
+ unsigned n = 0;
+
+ g = fopen(*f, "r");
+ if (!g) {
+ if (errno == ENOENT)
+ continue;
+
+ log_warning_errno(errno, "Failed to open %s: %m", *f);
+ continue;
+ }
+
+ FOREACH_LINE(line, g, log_warning_errno(errno, "Failed to read %s, ignoring: %m", *f)) {
+ char *l;
+
+ n++;
+
+ l = strstrip(line);
+ if (isempty(l))
+ continue;
+
+ if (*l == ';')
+ continue;
+
+ (void) loader(d, *f, n, l);
+ }
+ }
+
+ return 0;
+}
+
+static int domain_name_cmp(const void *a, const void *b) {
+ char **x = (char**) a, **y = (char**) b;
+
+ return dns_name_compare_func(*x, *y);
+}
+
+static int dns_trust_anchor_dump(DnsTrustAnchor *d) {
+ DnsAnswer *a;
+ Iterator i;
+
+ assert(d);
+
+ if (hashmap_isempty(d->positive_by_key))
+ log_info("No positive trust anchors defined.");
+ else {
+ log_info("Positive Trust Anchors:");
+ HASHMAP_FOREACH(a, d->positive_by_key, i) {
+ DnsResourceRecord *rr;
+
+ DNS_ANSWER_FOREACH(rr, a)
+ log_info("%s", dns_resource_record_to_string(rr));
+ }
+ }
+
+ if (set_isempty(d->negative_by_name))
+ log_info("No negative trust anchors defined.");
+ else {
+ _cleanup_free_ char **l = NULL, *j = NULL;
+
+ l = set_get_strv(d->negative_by_name);
+ if (!l)
+ return log_oom();
+
+ qsort_safe(l, set_size(d->negative_by_name), sizeof(char*), domain_name_cmp);
+
+ j = strv_join(l, " ");
+ if (!j)
+ return log_oom();
+
+ log_info("Negative trust anchors: %s", j);
+ }
+
+ return 0;
+}
+
+int dns_trust_anchor_load(DnsTrustAnchor *d) {
+ int r;
+
+ assert(d);
+
+ /* If loading things from disk fails, we don't consider this fatal */
+ (void) dns_trust_anchor_load_files(d, ".positive", dns_trust_anchor_load_positive);
+ (void) dns_trust_anchor_load_files(d, ".negative", dns_trust_anchor_load_negative);
+
+ /* However, if the built-in DS fails, then we have a problem. */
+ r = dns_trust_anchor_add_builtin_positive(d);
+ if (r < 0)
+ return log_error_errno(r, "Failed to add built-in positive trust anchor: %m");
+
+ r = dns_trust_anchor_add_builtin_negative(d);
+ if (r < 0)
+ return log_error_errno(r, "Failed to add built-in negative trust anchor: %m");
+
+ dns_trust_anchor_dump(d);
+
+ return 0;
+}
+
+void dns_trust_anchor_flush(DnsTrustAnchor *d) {
+ DnsAnswer *a;
+ DnsResourceRecord *rr;
+
+ assert(d);
+
+ while ((a = hashmap_steal_first(d->positive_by_key)))
+ dns_answer_unref(a);
+ d->positive_by_key = hashmap_free(d->positive_by_key);
+
+ while ((rr = set_steal_first(d->revoked_by_rr)))
+ dns_resource_record_unref(rr);
+ d->revoked_by_rr = set_free(d->revoked_by_rr);
+
+ d->negative_by_name = set_free_free(d->negative_by_name);
+}
+
+int dns_trust_anchor_lookup_positive(DnsTrustAnchor *d, const DnsResourceKey *key, DnsAnswer **ret) {
+ DnsAnswer *a;
+
+ assert(d);
+ assert(key);
+ assert(ret);
+
+ /* We only serve DS and DNSKEY RRs. */
+ if (!IN_SET(key->type, DNS_TYPE_DS, DNS_TYPE_DNSKEY))
+ return 0;
+
+ a = hashmap_get(d->positive_by_key, key);
+ if (!a)
+ return 0;
+
+ *ret = dns_answer_ref(a);
+ return 1;
+}
+
+int dns_trust_anchor_lookup_negative(DnsTrustAnchor *d, const char *name) {
+ assert(d);
+ assert(name);
+
+ return set_contains(d->negative_by_name, name);
+}
+
+static int dns_trust_anchor_revoked_put(DnsTrustAnchor *d, DnsResourceRecord *rr) {
+ int r;
+
+ assert(d);
+
+ r = set_ensure_allocated(&d->revoked_by_rr, &dns_resource_record_hash_ops);
+ if (r < 0)
+ return r;
+
+ r = set_put(d->revoked_by_rr, rr);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ dns_resource_record_ref(rr);
+
+ return r;
+}
+
+static int dns_trust_anchor_remove_revoked(DnsTrustAnchor *d, DnsResourceRecord *rr) {
+ _cleanup_(dns_answer_unrefp) DnsAnswer *new_answer = NULL;
+ DnsAnswer *old_answer;
+ int r;
+
+ /* Remember that this is a revoked trust anchor RR */
+ r = dns_trust_anchor_revoked_put(d, rr);
+ if (r < 0)
+ return r;
+
+ /* Remove this from the positive trust anchor */
+ old_answer = hashmap_get(d->positive_by_key, rr->key);
+ if (!old_answer)
+ return 0;
+
+ new_answer = dns_answer_ref(old_answer);
+
+ r = dns_answer_remove_by_rr(&new_answer, rr);
+ if (r <= 0)
+ return r;
+
+ /* We found the key! Warn the user */
+ log_struct(LOG_WARNING,
+ LOG_MESSAGE_ID(SD_MESSAGE_DNSSEC_TRUST_ANCHOR_REVOKED),
+ LOG_MESSAGE("DNSSEC Trust anchor %s has been revoked. Please update the trust anchor, or upgrade your operating system."), strna(dns_resource_record_to_string(rr)),
+ "TRUST_ANCHOR=%s", dns_resource_record_to_string(rr),
+ NULL);
+
+ if (dns_answer_size(new_answer) <= 0) {
+ assert_se(hashmap_remove(d->positive_by_key, rr->key) == old_answer);
+ dns_answer_unref(old_answer);
+ return 1;
+ }
+
+ r = hashmap_replace(d->positive_by_key, new_answer->items[0].rr->key, new_answer);
+ if (r < 0)
+ return r;
+
+ new_answer = NULL;
+ dns_answer_unref(old_answer);
+ return 1;
+}
+
+static int dns_trust_anchor_check_revoked_one(DnsTrustAnchor *d, DnsResourceRecord *revoked_dnskey) {
+ DnsAnswer *a;
+ int r;
+
+ assert(d);
+ assert(revoked_dnskey);
+ assert(revoked_dnskey->key->type == DNS_TYPE_DNSKEY);
+ assert(revoked_dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE);
+
+ a = hashmap_get(d->positive_by_key, revoked_dnskey->key);
+ if (a) {
+ DnsResourceRecord *anchor;
+
+ /* First, look for the precise DNSKEY in our trust anchor database */
+
+ DNS_ANSWER_FOREACH(anchor, a) {
+
+ if (anchor->dnskey.protocol != revoked_dnskey->dnskey.protocol)
+ continue;
+
+ if (anchor->dnskey.algorithm != revoked_dnskey->dnskey.algorithm)
+ continue;
+
+ if (anchor->dnskey.key_size != revoked_dnskey->dnskey.key_size)
+ continue;
+
+ /* Note that we allow the REVOKE bit to be
+ * different! It will be set in the revoked
+ * key, but unset in our version of it */
+ if (((anchor->dnskey.flags ^ revoked_dnskey->dnskey.flags) | DNSKEY_FLAG_REVOKE) != DNSKEY_FLAG_REVOKE)
+ continue;
+
+ if (memcmp(anchor->dnskey.key, revoked_dnskey->dnskey.key, anchor->dnskey.key_size) != 0)
+ continue;
+
+ dns_trust_anchor_remove_revoked(d, anchor);
+ break;
+ }
+ }
+
+ a = hashmap_get(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(revoked_dnskey->key->class, DNS_TYPE_DS, dns_resource_key_name(revoked_dnskey->key)));
+ if (a) {
+ DnsResourceRecord *anchor;
+
+ /* Second, look for DS RRs matching this DNSKEY in our trust anchor database */
+
+ DNS_ANSWER_FOREACH(anchor, a) {
+
+ /* We set mask_revoke to true here, since our
+ * DS fingerprint will be the one of the
+ * unrevoked DNSKEY, but the one we got passed
+ * here has the bit set. */
+ r = dnssec_verify_dnskey_by_ds(revoked_dnskey, anchor, true);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ dns_trust_anchor_remove_revoked(d, anchor);
+ break;
+ }
+ }
+
+ return 0;
+}
+
+int dns_trust_anchor_check_revoked(DnsTrustAnchor *d, DnsResourceRecord *dnskey, DnsAnswer *rrs) {
+ DnsResourceRecord *rrsig;
+ int r;
+
+ assert(d);
+ assert(dnskey);
+
+ /* Looks if "dnskey" is a self-signed RR that has been revoked
+ * and matches one of our trust anchor entries. If so, removes
+ * it from the trust anchor and returns > 0. */
+
+ if (dnskey->key->type != DNS_TYPE_DNSKEY)
+ return 0;
+
+ /* Is this DNSKEY revoked? */
+ if ((dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE) == 0)
+ return 0;
+
+ /* Could this be interesting to us at all? If not,
+ * there's no point in looking for and verifying a
+ * self-signed RRSIG. */
+ if (!dns_trust_anchor_knows_domain_positive(d, dns_resource_key_name(dnskey->key)))
+ return 0;
+
+ /* Look for a self-signed RRSIG in the other rrs belonging to this DNSKEY */
+ DNS_ANSWER_FOREACH(rrsig, rrs) {
+ DnssecResult result;
+
+ if (rrsig->key->type != DNS_TYPE_RRSIG)
+ continue;
+
+ r = dnssec_rrsig_match_dnskey(rrsig, dnskey, true);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ r = dnssec_verify_rrset(rrs, dnskey->key, rrsig, dnskey, USEC_INFINITY, &result);
+ if (r < 0)
+ return r;
+ if (result != DNSSEC_VALIDATED)
+ continue;
+
+ /* Bingo! This is a revoked self-signed DNSKEY. Let's
+ * see if this precise one exists in our trust anchor
+ * database, too. */
+ r = dns_trust_anchor_check_revoked_one(d, dnskey);
+ if (r < 0)
+ return r;
+
+ return 1;
+ }
+
+ return 0;
+}
+
+int dns_trust_anchor_is_revoked(DnsTrustAnchor *d, DnsResourceRecord *rr) {
+ assert(d);
+
+ if (!IN_SET(rr->key->type, DNS_TYPE_DS, DNS_TYPE_DNSKEY))
+ return 0;
+
+ return set_contains(d->revoked_by_rr, rr);
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-trust-anchor.h b/src/grp-resolve/systemd-resolved/resolved-dns-trust-anchor.h
new file mode 100644
index 0000000000..9039bd7aa3
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-trust-anchor.h
@@ -0,0 +1,43 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2015 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "basic-dns/resolved-dns-answer.h"
+#include "basic-dns/resolved-dns-rr.h"
+#include "systemd-basic/hashmap.h"
+
+typedef struct DnsTrustAnchor DnsTrustAnchor;
+
+/* This contains a fixed database mapping domain names to DS or DNSKEY records. */
+
+struct DnsTrustAnchor {
+ Hashmap *positive_by_key;
+ Set *negative_by_name;
+ Set *revoked_by_rr;
+};
+
+int dns_trust_anchor_load(DnsTrustAnchor *d);
+void dns_trust_anchor_flush(DnsTrustAnchor *d);
+
+int dns_trust_anchor_lookup_positive(DnsTrustAnchor *d, const DnsResourceKey* key, DnsAnswer **answer);
+int dns_trust_anchor_lookup_negative(DnsTrustAnchor *d, const char *name);
+
+int dns_trust_anchor_check_revoked(DnsTrustAnchor *d, DnsResourceRecord *dnskey, DnsAnswer *rrs);
+int dns_trust_anchor_is_revoked(DnsTrustAnchor *d, DnsResourceRecord *rr);
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-zone.c b/src/grp-resolve/systemd-resolved/resolved-dns-zone.c
new file mode 100644
index 0000000000..723df26454
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-zone.c
@@ -0,0 +1,665 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "basic-dns/resolved-dns-packet.h"
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/list.h"
+#include "systemd-basic/string-util.h"
+#include "systemd-shared/dns-domain.h"
+
+#include "resolved-dns-zone.h"
+
+/* Never allow more than 1K entries */
+#define ZONE_MAX 1024
+
+void dns_zone_item_probe_stop(DnsZoneItem *i) {
+ DnsTransaction *t;
+ assert(i);
+
+ if (!i->probe_transaction)
+ return;
+
+ t = i->probe_transaction;
+ i->probe_transaction = NULL;
+
+ set_remove(t->notify_zone_items, i);
+ set_remove(t->notify_zone_items_done, i);
+ dns_transaction_gc(t);
+}
+
+static void dns_zone_item_free(DnsZoneItem *i) {
+ if (!i)
+ return;
+
+ dns_zone_item_probe_stop(i);
+ dns_resource_record_unref(i->rr);
+
+ free(i);
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(DnsZoneItem*, dns_zone_item_free);
+
+static void dns_zone_item_remove_and_free(DnsZone *z, DnsZoneItem *i) {
+ DnsZoneItem *first;
+
+ assert(z);
+
+ if (!i)
+ return;
+
+ first = hashmap_get(z->by_key, i->rr->key);
+ LIST_REMOVE(by_key, first, i);
+ if (first)
+ assert_se(hashmap_replace(z->by_key, first->rr->key, first) >= 0);
+ else
+ hashmap_remove(z->by_key, i->rr->key);
+
+ first = hashmap_get(z->by_name, dns_resource_key_name(i->rr->key));
+ LIST_REMOVE(by_name, first, i);
+ if (first)
+ assert_se(hashmap_replace(z->by_name, dns_resource_key_name(first->rr->key), first) >= 0);
+ else
+ hashmap_remove(z->by_name, dns_resource_key_name(i->rr->key));
+
+ dns_zone_item_free(i);
+}
+
+void dns_zone_flush(DnsZone *z) {
+ DnsZoneItem *i;
+
+ assert(z);
+
+ while ((i = hashmap_first(z->by_key)))
+ dns_zone_item_remove_and_free(z, i);
+
+ assert(hashmap_size(z->by_key) == 0);
+ assert(hashmap_size(z->by_name) == 0);
+
+ z->by_key = hashmap_free(z->by_key);
+ z->by_name = hashmap_free(z->by_name);
+}
+
+static DnsZoneItem* dns_zone_get(DnsZone *z, DnsResourceRecord *rr) {
+ DnsZoneItem *i;
+
+ assert(z);
+ assert(rr);
+
+ LIST_FOREACH(by_key, i, hashmap_get(z->by_key, rr->key))
+ if (dns_resource_record_equal(i->rr, rr) > 0)
+ return i;
+
+ return NULL;
+}
+
+void dns_zone_remove_rr(DnsZone *z, DnsResourceRecord *rr) {
+ DnsZoneItem *i;
+
+ assert(z);
+ assert(rr);
+
+ i = dns_zone_get(z, rr);
+ if (i)
+ dns_zone_item_remove_and_free(z, i);
+}
+
+static int dns_zone_init(DnsZone *z) {
+ int r;
+
+ assert(z);
+
+ r = hashmap_ensure_allocated(&z->by_key, &dns_resource_key_hash_ops);
+ if (r < 0)
+ return r;
+
+ r = hashmap_ensure_allocated(&z->by_name, &dns_name_hash_ops);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+static int dns_zone_link_item(DnsZone *z, DnsZoneItem *i) {
+ DnsZoneItem *first;
+ int r;
+
+ first = hashmap_get(z->by_key, i->rr->key);
+ if (first) {
+ LIST_PREPEND(by_key, first, i);
+ assert_se(hashmap_replace(z->by_key, first->rr->key, first) >= 0);
+ } else {
+ r = hashmap_put(z->by_key, i->rr->key, i);
+ if (r < 0)
+ return r;
+ }
+
+ first = hashmap_get(z->by_name, dns_resource_key_name(i->rr->key));
+ if (first) {
+ LIST_PREPEND(by_name, first, i);
+ assert_se(hashmap_replace(z->by_name, dns_resource_key_name(first->rr->key), first) >= 0);
+ } else {
+ r = hashmap_put(z->by_name, dns_resource_key_name(i->rr->key), i);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static int dns_zone_item_probe_start(DnsZoneItem *i) {
+ DnsTransaction *t;
+ int r;
+
+ assert(i);
+
+ if (i->probe_transaction)
+ return 0;
+
+ t = dns_scope_find_transaction(i->scope, &DNS_RESOURCE_KEY_CONST(i->rr->key->class, DNS_TYPE_ANY, dns_resource_key_name(i->rr->key)), false);
+ if (!t) {
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+ key = dns_resource_key_new(i->rr->key->class, DNS_TYPE_ANY, dns_resource_key_name(i->rr->key));
+ if (!key)
+ return -ENOMEM;
+
+ r = dns_transaction_new(&t, i->scope, key);
+ if (r < 0)
+ return r;
+ }
+
+ r = set_ensure_allocated(&t->notify_zone_items, NULL);
+ if (r < 0)
+ goto gc;
+
+ r = set_ensure_allocated(&t->notify_zone_items_done, NULL);
+ if (r < 0)
+ goto gc;
+
+ r = set_put(t->notify_zone_items, i);
+ if (r < 0)
+ goto gc;
+
+ i->probe_transaction = t;
+
+ if (t->state == DNS_TRANSACTION_NULL) {
+
+ i->block_ready++;
+ r = dns_transaction_go(t);
+ i->block_ready--;
+
+ if (r < 0) {
+ dns_zone_item_probe_stop(i);
+ return r;
+ }
+ }
+
+ dns_zone_item_notify(i);
+ return 0;
+
+gc:
+ dns_transaction_gc(t);
+ return r;
+}
+
+int dns_zone_put(DnsZone *z, DnsScope *s, DnsResourceRecord *rr, bool probe) {
+ _cleanup_(dns_zone_item_freep) DnsZoneItem *i = NULL;
+ DnsZoneItem *existing;
+ int r;
+
+ assert(z);
+ assert(s);
+ assert(rr);
+
+ if (dns_class_is_pseudo(rr->key->class))
+ return -EINVAL;
+ if (dns_type_is_pseudo(rr->key->type))
+ return -EINVAL;
+
+ existing = dns_zone_get(z, rr);
+ if (existing)
+ return 0;
+
+ r = dns_zone_init(z);
+ if (r < 0)
+ return r;
+
+ i = new0(DnsZoneItem, 1);
+ if (!i)
+ return -ENOMEM;
+
+ i->scope = s;
+ i->rr = dns_resource_record_ref(rr);
+ i->probing_enabled = probe;
+
+ r = dns_zone_link_item(z, i);
+ if (r < 0)
+ return r;
+
+ if (probe) {
+ DnsZoneItem *first, *j;
+ bool established = false;
+
+ /* Check if there's already an RR with the same name
+ * established. If so, it has been probed already, and
+ * we don't ned to probe again. */
+
+ LIST_FIND_HEAD(by_name, i, first);
+ LIST_FOREACH(by_name, j, first) {
+ if (i == j)
+ continue;
+
+ if (j->state == DNS_ZONE_ITEM_ESTABLISHED)
+ established = true;
+ }
+
+ if (established)
+ i->state = DNS_ZONE_ITEM_ESTABLISHED;
+ else {
+ i->state = DNS_ZONE_ITEM_PROBING;
+
+ r = dns_zone_item_probe_start(i);
+ if (r < 0) {
+ dns_zone_item_remove_and_free(z, i);
+ i = NULL;
+ return r;
+ }
+ }
+ } else
+ i->state = DNS_ZONE_ITEM_ESTABLISHED;
+
+ i = NULL;
+ return 0;
+}
+
+int dns_zone_lookup(DnsZone *z, DnsResourceKey *key, int ifindex, DnsAnswer **ret_answer, DnsAnswer **ret_soa, bool *ret_tentative) {
+ _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL, *soa = NULL;
+ unsigned n_answer = 0;
+ DnsZoneItem *j, *first;
+ bool tentative = true, need_soa = false;
+ int r;
+
+ /* Note that we don't actually need the ifindex for anything. However when it is passed we'll initialize the
+ * ifindex field in the answer with it */
+
+ assert(z);
+ assert(key);
+ assert(ret_answer);
+
+ /* First iteration, count what we have */
+
+ if (key->type == DNS_TYPE_ANY || key->class == DNS_CLASS_ANY) {
+ bool found = false, added = false;
+ int k;
+
+ /* If this is a generic match, then we have to
+ * go through the list by the name and look
+ * for everything manually */
+
+ first = hashmap_get(z->by_name, dns_resource_key_name(key));
+ LIST_FOREACH(by_name, j, first) {
+ if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING))
+ continue;
+
+ found = true;
+
+ k = dns_resource_key_match_rr(key, j->rr, NULL);
+ if (k < 0)
+ return k;
+ if (k > 0) {
+ n_answer++;
+ added = true;
+ }
+
+ }
+
+ if (found && !added)
+ need_soa = true;
+
+ } else {
+ bool found = false;
+
+ /* If this is a specific match, then look for
+ * the right key immediately */
+
+ first = hashmap_get(z->by_key, key);
+ LIST_FOREACH(by_key, j, first) {
+ if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING))
+ continue;
+
+ found = true;
+ n_answer++;
+ }
+
+ if (!found) {
+ first = hashmap_get(z->by_name, dns_resource_key_name(key));
+ LIST_FOREACH(by_name, j, first) {
+ if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING))
+ continue;
+
+ need_soa = true;
+ break;
+ }
+ }
+ }
+
+ if (n_answer <= 0 && !need_soa)
+ goto return_empty;
+
+ if (n_answer > 0) {
+ answer = dns_answer_new(n_answer);
+ if (!answer)
+ return -ENOMEM;
+ }
+
+ if (need_soa) {
+ soa = dns_answer_new(1);
+ if (!soa)
+ return -ENOMEM;
+ }
+
+ /* Second iteration, actually add the RRs to the answers */
+ if (key->type == DNS_TYPE_ANY || key->class == DNS_CLASS_ANY) {
+ bool found = false, added = false;
+ int k;
+
+ first = hashmap_get(z->by_name, dns_resource_key_name(key));
+ LIST_FOREACH(by_name, j, first) {
+ if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING))
+ continue;
+
+ found = true;
+
+ if (j->state != DNS_ZONE_ITEM_PROBING)
+ tentative = false;
+
+ k = dns_resource_key_match_rr(key, j->rr, NULL);
+ if (k < 0)
+ return k;
+ if (k > 0) {
+ r = dns_answer_add(answer, j->rr, ifindex, DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+
+ added = true;
+ }
+ }
+
+ if (found && !added) {
+ r = dns_answer_add_soa(soa, dns_resource_key_name(key), LLMNR_DEFAULT_TTL, ifindex);
+ if (r < 0)
+ return r;
+ }
+ } else {
+ bool found = false;
+
+ first = hashmap_get(z->by_key, key);
+ LIST_FOREACH(by_key, j, first) {
+ if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING))
+ continue;
+
+ found = true;
+
+ if (j->state != DNS_ZONE_ITEM_PROBING)
+ tentative = false;
+
+ r = dns_answer_add(answer, j->rr, ifindex, DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+ }
+
+ if (!found) {
+ bool add_soa = false;
+
+ first = hashmap_get(z->by_name, dns_resource_key_name(key));
+ LIST_FOREACH(by_name, j, first) {
+ if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING))
+ continue;
+
+ if (j->state != DNS_ZONE_ITEM_PROBING)
+ tentative = false;
+
+ add_soa = true;
+ }
+
+ if (add_soa) {
+ r = dns_answer_add_soa(soa, dns_resource_key_name(key), LLMNR_DEFAULT_TTL, ifindex);
+ if (r < 0)
+ return r;
+ }
+ }
+ }
+
+ /* If the caller sets ret_tentative to NULL, then use this as
+ * indication to not return tentative entries */
+
+ if (!ret_tentative && tentative)
+ goto return_empty;
+
+ *ret_answer = answer;
+ answer = NULL;
+
+ if (ret_soa) {
+ *ret_soa = soa;
+ soa = NULL;
+ }
+
+ if (ret_tentative)
+ *ret_tentative = tentative;
+
+ return 1;
+
+return_empty:
+ *ret_answer = NULL;
+
+ if (ret_soa)
+ *ret_soa = NULL;
+
+ if (ret_tentative)
+ *ret_tentative = false;
+
+ return 0;
+}
+
+void dns_zone_item_conflict(DnsZoneItem *i) {
+ assert(i);
+
+ if (!IN_SET(i->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_VERIFYING, DNS_ZONE_ITEM_ESTABLISHED))
+ return;
+
+ log_info("Detected conflict on %s", strna(dns_resource_record_to_string(i->rr)));
+
+ dns_zone_item_probe_stop(i);
+
+ /* Withdraw the conflict item */
+ i->state = DNS_ZONE_ITEM_WITHDRAWN;
+
+ /* Maybe change the hostname */
+ if (manager_is_own_hostname(i->scope->manager, dns_resource_key_name(i->rr->key)) > 0)
+ manager_next_hostname(i->scope->manager);
+}
+
+void dns_zone_item_notify(DnsZoneItem *i) {
+ assert(i);
+ assert(i->probe_transaction);
+
+ if (i->block_ready > 0)
+ return;
+
+ if (IN_SET(i->probe_transaction->state, DNS_TRANSACTION_NULL, DNS_TRANSACTION_PENDING, DNS_TRANSACTION_VALIDATING))
+ return;
+
+ if (i->probe_transaction->state == DNS_TRANSACTION_SUCCESS) {
+ bool we_lost = false;
+
+ /* The probe got a successful reply. If we so far
+ * weren't established we just give up. If we already
+ * were established, and the peer has the
+ * lexicographically larger IP address we continue
+ * and defend it. */
+
+ if (!IN_SET(i->state, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING)) {
+ log_debug("Got a successful probe for not yet established RR, we lost.");
+ we_lost = true;
+ } else {
+ assert(i->probe_transaction->received);
+ we_lost = memcmp(&i->probe_transaction->received->sender, &i->probe_transaction->received->destination, FAMILY_ADDRESS_SIZE(i->probe_transaction->received->family)) < 0;
+ if (we_lost)
+ log_debug("Got a successful probe reply for an established RR, and we have a lexicographically larger IP address and thus lost.");
+ }
+
+ if (we_lost) {
+ dns_zone_item_conflict(i);
+ return;
+ }
+
+ log_debug("Got a successful probe reply, but peer has lexicographically lower IP address and thus lost.");
+ }
+
+ log_debug("Record %s successfully probed.", strna(dns_resource_record_to_string(i->rr)));
+
+ dns_zone_item_probe_stop(i);
+ i->state = DNS_ZONE_ITEM_ESTABLISHED;
+}
+
+static int dns_zone_item_verify(DnsZoneItem *i) {
+ int r;
+
+ assert(i);
+
+ if (i->state != DNS_ZONE_ITEM_ESTABLISHED)
+ return 0;
+
+ log_debug("Verifying RR %s", strna(dns_resource_record_to_string(i->rr)));
+
+ i->state = DNS_ZONE_ITEM_VERIFYING;
+ r = dns_zone_item_probe_start(i);
+ if (r < 0) {
+ log_error_errno(r, "Failed to start probing for verifying RR: %m");
+ i->state = DNS_ZONE_ITEM_ESTABLISHED;
+ return r;
+ }
+
+ return 0;
+}
+
+int dns_zone_check_conflicts(DnsZone *zone, DnsResourceRecord *rr) {
+ DnsZoneItem *i, *first;
+ int c = 0;
+
+ assert(zone);
+ assert(rr);
+
+ /* This checks whether a response RR we received from somebody
+ * else is one that we actually thought was uniquely ours. If
+ * so, we'll verify our RRs. */
+
+ /* No conflict if we don't have the name at all. */
+ first = hashmap_get(zone->by_name, dns_resource_key_name(rr->key));
+ if (!first)
+ return 0;
+
+ /* No conflict if we have the exact same RR */
+ if (dns_zone_get(zone, rr))
+ return 0;
+
+ /* OK, somebody else has RRs for the same name. Yuck! Let's
+ * start probing again */
+
+ LIST_FOREACH(by_name, i, first) {
+ if (dns_resource_record_equal(i->rr, rr))
+ continue;
+
+ dns_zone_item_verify(i);
+ c++;
+ }
+
+ return c;
+}
+
+int dns_zone_verify_conflicts(DnsZone *zone, DnsResourceKey *key) {
+ DnsZoneItem *i, *first;
+ int c = 0;
+
+ assert(zone);
+
+ /* Somebody else notified us about a possible conflict. Let's
+ * verify if that's true. */
+
+ first = hashmap_get(zone->by_name, dns_resource_key_name(key));
+ if (!first)
+ return 0;
+
+ LIST_FOREACH(by_name, i, first) {
+ dns_zone_item_verify(i);
+ c++;
+ }
+
+ return c;
+}
+
+void dns_zone_verify_all(DnsZone *zone) {
+ DnsZoneItem *i;
+ Iterator iterator;
+
+ assert(zone);
+
+ HASHMAP_FOREACH(i, zone->by_key, iterator) {
+ DnsZoneItem *j;
+
+ LIST_FOREACH(by_key, j, i)
+ dns_zone_item_verify(j);
+ }
+}
+
+void dns_zone_dump(DnsZone *zone, FILE *f) {
+ Iterator iterator;
+ DnsZoneItem *i;
+
+ if (!zone)
+ return;
+
+ if (!f)
+ f = stdout;
+
+ HASHMAP_FOREACH(i, zone->by_key, iterator) {
+ DnsZoneItem *j;
+
+ LIST_FOREACH(by_key, j, i) {
+ const char *t;
+
+ t = dns_resource_record_to_string(j->rr);
+ if (!t) {
+ log_oom();
+ continue;
+ }
+
+ fputc('\t', f);
+ fputs(t, f);
+ fputc('\n', f);
+ }
+ }
+}
+
+bool dns_zone_is_empty(DnsZone *zone) {
+ if (!zone)
+ return true;
+
+ return hashmap_isempty(zone->by_key);
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-dns-zone.h b/src/grp-resolve/systemd-resolved/resolved-dns-zone.h
new file mode 100644
index 0000000000..fe656be793
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-dns-zone.h
@@ -0,0 +1,82 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "systemd-basic/hashmap.h"
+
+typedef struct DnsZone {
+ Hashmap *by_key;
+ Hashmap *by_name;
+} DnsZone;
+
+#include "basic-dns/resolved-dns-answer.h"
+#include "basic-dns/resolved-dns-question.h"
+#include "basic-dns/resolved-dns-rr.h"
+
+typedef enum DnsZoneItemState DnsZoneItemState;
+typedef struct DnsZoneItem DnsZoneItem;
+
+#include "resolved-dns-transaction.h"
+
+/* RFC 4795 Section 2.8. suggests a TTL of 30s by default */
+#define LLMNR_DEFAULT_TTL (30)
+
+enum DnsZoneItemState {
+ DNS_ZONE_ITEM_PROBING,
+ DNS_ZONE_ITEM_ESTABLISHED,
+ DNS_ZONE_ITEM_VERIFYING,
+ DNS_ZONE_ITEM_WITHDRAWN,
+};
+
+struct DnsZoneItem {
+ DnsScope *scope;
+ DnsResourceRecord *rr;
+
+ DnsZoneItemState state;
+
+ unsigned block_ready;
+
+ bool probing_enabled;
+
+ LIST_FIELDS(DnsZoneItem, by_key);
+ LIST_FIELDS(DnsZoneItem, by_name);
+
+ DnsTransaction *probe_transaction;
+};
+
+void dns_zone_flush(DnsZone *z);
+
+int dns_zone_put(DnsZone *z, DnsScope *s, DnsResourceRecord *rr, bool probe);
+void dns_zone_remove_rr(DnsZone *z, DnsResourceRecord *rr);
+
+int dns_zone_lookup(DnsZone *z, DnsResourceKey *key, int ifindex, DnsAnswer **answer, DnsAnswer **soa, bool *tentative);
+
+void dns_zone_item_conflict(DnsZoneItem *i);
+void dns_zone_item_notify(DnsZoneItem *i);
+
+int dns_zone_check_conflicts(DnsZone *zone, DnsResourceRecord *rr);
+int dns_zone_verify_conflicts(DnsZone *zone, DnsResourceKey *key);
+
+void dns_zone_verify_all(DnsZone *zone);
+
+void dns_zone_item_probe_stop(DnsZoneItem *i);
+
+void dns_zone_dump(DnsZone *zone, FILE *f);
+bool dns_zone_is_empty(DnsZone *zone);
diff --git a/src/grp-resolve/systemd-resolved/resolved-etc-hosts.c b/src/grp-resolve/systemd-resolved/resolved-etc-hosts.c
new file mode 100644
index 0000000000..942c06605e
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-etc-hosts.c
@@ -0,0 +1,449 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2016 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "systemd-basic/fd-util.h"
+#include "systemd-basic/fileio.h"
+#include "systemd-basic/hostname-util.h"
+#include "systemd-basic/string-util.h"
+#include "systemd-basic/strv.h"
+#include "systemd-basic/time-util.h"
+
+#include "resolved-dns-synthesize.h"
+#include "resolved-etc-hosts.h"
+
+/* Recheck /etc/hosts at most once every 2s */
+#define ETC_HOSTS_RECHECK_USEC (2*USEC_PER_SEC)
+
+typedef struct EtcHostsItem {
+ int family;
+ union in_addr_union address;
+
+ char **names;
+} EtcHostsItem;
+
+typedef struct EtcHostsItemByName {
+ char *name;
+
+ EtcHostsItem **items;
+ size_t n_items, n_allocated;
+} EtcHostsItemByName;
+
+void manager_etc_hosts_flush(Manager *m) {
+ EtcHostsItem *item;
+ EtcHostsItemByName *bn;
+
+ while ((item = set_steal_first(m->etc_hosts_by_address))) {
+ strv_free(item->names);
+ free(item);
+ }
+
+ while ((bn = hashmap_steal_first(m->etc_hosts_by_name))) {
+ free(bn->name);
+ free(bn->items);
+ free(bn);
+ }
+
+ m->etc_hosts_by_address = set_free(m->etc_hosts_by_address);
+ m->etc_hosts_by_name = hashmap_free(m->etc_hosts_by_name);
+
+ m->etc_hosts_mtime = USEC_INFINITY;
+}
+
+static void etc_hosts_item_hash_func(const void *p, struct siphash *state) {
+ const EtcHostsItem *item = p;
+
+ siphash24_compress(&item->family, sizeof(item->family), state);
+
+ if (item->family == AF_INET)
+ siphash24_compress(&item->address.in, sizeof(item->address.in), state);
+ else if (item->family == AF_INET6)
+ siphash24_compress(&item->address.in6, sizeof(item->address.in6), state);
+}
+
+static int etc_hosts_item_compare_func(const void *a, const void *b) {
+ const EtcHostsItem *x = a, *y = b;
+
+ if (x->family != y->family)
+ return x->family - y->family;
+
+ if (x->family == AF_INET)
+ return memcmp(&x->address.in.s_addr, &y->address.in.s_addr, sizeof(struct in_addr));
+
+ if (x->family == AF_INET6)
+ return memcmp(&x->address.in6.s6_addr, &y->address.in6.s6_addr, sizeof(struct in6_addr));
+
+ return trivial_compare_func(a, b);
+}
+
+static const struct hash_ops etc_hosts_item_ops = {
+ .hash = etc_hosts_item_hash_func,
+ .compare = etc_hosts_item_compare_func,
+};
+
+static int add_item(Manager *m, int family, const union in_addr_union *address, char **names) {
+
+ EtcHostsItem key = {
+ .family = family,
+ .address = *address,
+ };
+ EtcHostsItem *item;
+ char **n;
+ int r;
+
+ assert(m);
+ assert(address);
+
+ r = in_addr_is_null(family, address);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ /* This is an 0.0.0.0 or :: item, which we assume means that we shall map the specified hostname to
+ * nothing. */
+ item = NULL;
+ else {
+ /* If this is a normal address, then, simply add entry mapping it to the specified names */
+
+ item = set_get(m->etc_hosts_by_address, &key);
+ if (item) {
+ r = strv_extend_strv(&item->names, names, true);
+ if (r < 0)
+ return log_oom();
+ } else {
+
+ r = set_ensure_allocated(&m->etc_hosts_by_address, &etc_hosts_item_ops);
+ if (r < 0)
+ return log_oom();
+
+ item = new0(EtcHostsItem, 1);
+ if (!item)
+ return log_oom();
+
+ item->family = family;
+ item->address = *address;
+ item->names = names;
+
+ r = set_put(m->etc_hosts_by_address, item);
+ if (r < 0) {
+ free(item);
+ return log_oom();
+ }
+ }
+ }
+
+ STRV_FOREACH(n, names) {
+ EtcHostsItemByName *bn;
+
+ bn = hashmap_get(m->etc_hosts_by_name, *n);
+ if (!bn) {
+ r = hashmap_ensure_allocated(&m->etc_hosts_by_name, &dns_name_hash_ops);
+ if (r < 0)
+ return log_oom();
+
+ bn = new0(EtcHostsItemByName, 1);
+ if (!bn)
+ return log_oom();
+
+ bn->name = strdup(*n);
+ if (!bn->name) {
+ free(bn);
+ return log_oom();
+ }
+
+ r = hashmap_put(m->etc_hosts_by_name, bn->name, bn);
+ if (r < 0) {
+ free(bn->name);
+ free(bn);
+ return log_oom();
+ }
+ }
+
+ if (item) {
+ if (!GREEDY_REALLOC(bn->items, bn->n_allocated, bn->n_items+1))
+ return log_oom();
+
+ bn->items[bn->n_items++] = item;
+ }
+ }
+
+ return 0;
+}
+
+static int parse_line(Manager *m, unsigned nr, const char *line) {
+ _cleanup_free_ char *address = NULL;
+ _cleanup_strv_free_ char **names = NULL;
+ union in_addr_union in;
+ bool suppressed = false;
+ int family, r;
+
+ assert(m);
+ assert(line);
+
+ r = extract_first_word(&line, &address, NULL, EXTRACT_RELAX);
+ if (r < 0)
+ return log_error_errno(r, "Couldn't extract address, in line /etc/hosts:%u.", nr);
+ if (r == 0) {
+ log_error("Premature end of line, in line /etc/hosts:%u.", nr);
+ return -EINVAL;
+ }
+
+ r = in_addr_from_string_auto(address, &family, &in);
+ if (r < 0)
+ return log_error_errno(r, "Address '%s' is invalid, in line /etc/hosts:%u.", address, nr);
+
+ for (;;) {
+ _cleanup_free_ char *name = NULL;
+
+ r = extract_first_word(&line, &name, NULL, EXTRACT_RELAX);
+ if (r < 0)
+ return log_error_errno(r, "Couldn't extract host name, in line /etc/hosts:%u.", nr);
+ if (r == 0)
+ break;
+
+ r = dns_name_is_valid(name);
+ if (r <= 0)
+ return log_error_errno(r, "Hostname %s is not valid, ignoring, in line /etc/hosts:%u.", name, nr);
+
+ if (is_localhost(name)) {
+ /* Suppress the "localhost" line that is often seen */
+ suppressed = true;
+ continue;
+ }
+
+ r = strv_push(&names, name);
+ if (r < 0)
+ return log_oom();
+
+ name = NULL;
+ }
+
+ if (strv_isempty(names)) {
+
+ if (suppressed)
+ return 0;
+
+ log_error("Line is missing any host names, in line /etc/hosts:%u.", nr);
+ return -EINVAL;
+ }
+
+ /* Takes possession of the names strv */
+ r = add_item(m, family, &in, names);
+ if (r < 0)
+ return r;
+
+ names = NULL;
+ return r;
+}
+
+int manager_etc_hosts_read(Manager *m) {
+ _cleanup_fclose_ FILE *f = NULL;
+ char line[LINE_MAX];
+ struct stat st;
+ usec_t ts;
+ unsigned nr = 0;
+ int r;
+
+ assert_se(sd_event_now(m->event, clock_boottime_or_monotonic(), &ts) >= 0);
+
+ /* See if we checked /etc/hosts recently already */
+ if (m->etc_hosts_last != USEC_INFINITY && m->etc_hosts_last + ETC_HOSTS_RECHECK_USEC > ts)
+ return 0;
+
+ m->etc_hosts_last = ts;
+
+ if (m->etc_hosts_mtime != USEC_INFINITY) {
+ if (stat("/etc/hosts", &st) < 0) {
+ if (errno == ENOENT) {
+ r = 0;
+ goto clear;
+ }
+
+ return log_error_errno(errno, "Failed to stat /etc/hosts: %m");
+ }
+
+ /* Did the mtime change? If not, there's no point in re-reading the file. */
+ if (timespec_load(&st.st_mtim) == m->etc_hosts_mtime)
+ return 0;
+ }
+
+ f = fopen("/etc/hosts", "re");
+ if (!f) {
+ if (errno == ENOENT) {
+ r = 0;
+ goto clear;
+ }
+
+ return log_error_errno(errno, "Failed to open /etc/hosts: %m");
+ }
+
+ /* Take the timestamp at the beginning of processing, so that any changes made later are read on the next
+ * invocation */
+ r = fstat(fileno(f), &st);
+ if (r < 0)
+ return log_error_errno(errno, "Failed to fstat() /etc/hosts: %m");
+
+ manager_etc_hosts_flush(m);
+
+ FOREACH_LINE(line, f, return log_error_errno(errno, "Failed to read /etc/hosts: %m")) {
+ char *l;
+
+ nr++;
+
+ l = strstrip(line);
+ if (isempty(l))
+ continue;
+ if (l[0] == '#')
+ continue;
+
+ r = parse_line(m, nr, l);
+ if (r == -ENOMEM) /* On OOM we abandon the half-built-up structure. All other errors we ignore and proceed */
+ goto clear;
+ }
+
+ m->etc_hosts_mtime = timespec_load(&st.st_mtim);
+ m->etc_hosts_last = ts;
+
+ return 1;
+
+clear:
+ manager_etc_hosts_flush(m);
+ return r;
+}
+
+int manager_etc_hosts_lookup(Manager *m, DnsQuestion* q, DnsAnswer **answer) {
+ bool found_a = false, found_aaaa = false;
+ EtcHostsItemByName *bn;
+ EtcHostsItem k = {};
+ DnsResourceKey *t;
+ const char *name;
+ unsigned i;
+ int r;
+
+ assert(m);
+ assert(q);
+ assert(answer);
+
+ r = manager_etc_hosts_read(m);
+ if (r < 0)
+ return r;
+
+ name = dns_question_first_name(q);
+ if (!name)
+ return 0;
+
+ r = dns_name_address(name, &k.family, &k.address);
+ if (r > 0) {
+ EtcHostsItem *item;
+ DnsResourceKey *found_ptr = NULL;
+
+ item = set_get(m->etc_hosts_by_address, &k);
+ if (!item)
+ return 0;
+
+ /* We have an address in /etc/hosts that matches the queried name. Let's return successful. Actual data
+ * we'll only return if the request was for PTR. */
+
+ DNS_QUESTION_FOREACH(t, q) {
+ if (!IN_SET(t->type, DNS_TYPE_PTR, DNS_TYPE_ANY))
+ continue;
+ if (!IN_SET(t->class, DNS_CLASS_IN, DNS_CLASS_ANY))
+ continue;
+
+ r = dns_name_equal(dns_resource_key_name(t), name);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ found_ptr = t;
+ break;
+ }
+ }
+
+ if (found_ptr) {
+ char **n;
+
+ r = dns_answer_reserve(answer, strv_length(item->names));
+ if (r < 0)
+ return r;
+
+ STRV_FOREACH(n, item->names) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+ rr = dns_resource_record_new(found_ptr);
+ if (!rr)
+ return -ENOMEM;
+
+ rr->ptr.name = strdup(*n);
+ if (!rr->ptr.name)
+ return -ENOMEM;
+
+ r = dns_answer_add(*answer, rr, 0, DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+ }
+ }
+
+ return 1;
+ }
+
+ bn = hashmap_get(m->etc_hosts_by_name, name);
+ if (!bn)
+ return 0;
+
+ r = dns_answer_reserve(answer, bn->n_items);
+ if (r < 0)
+ return r;
+
+ DNS_QUESTION_FOREACH(t, q) {
+ if (!IN_SET(t->type, DNS_TYPE_A, DNS_TYPE_AAAA, DNS_TYPE_ANY))
+ continue;
+ if (!IN_SET(t->class, DNS_CLASS_IN, DNS_CLASS_ANY))
+ continue;
+
+ r = dns_name_equal(dns_resource_key_name(t), name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ if (IN_SET(t->type, DNS_TYPE_A, DNS_TYPE_ANY))
+ found_a = true;
+ if (IN_SET(t->type, DNS_TYPE_AAAA, DNS_TYPE_ANY))
+ found_aaaa = true;
+
+ if (found_a && found_aaaa)
+ break;
+ }
+
+ for (i = 0; i < bn->n_items; i++) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+ if ((found_a && bn->items[i]->family != AF_INET) &&
+ (found_aaaa && bn->items[i]->family != AF_INET6))
+ continue;
+
+ r = dns_resource_record_new_address(&rr, bn->items[i]->family, &bn->items[i]->address, bn->name);
+ if (r < 0)
+ return r;
+
+ r = dns_answer_add(*answer, rr, 0, DNS_ANSWER_AUTHENTICATED);
+ if (r < 0)
+ return r;
+ }
+
+ return 1;
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-etc-hosts.h b/src/grp-resolve/systemd-resolved/resolved-etc-hosts.h
new file mode 100644
index 0000000000..49e449b56d
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-etc-hosts.h
@@ -0,0 +1,29 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2016 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "basic-dns/resolved-dns-answer.h"
+#include "basic-dns/resolved-dns-question.h"
+
+#include "resolved-manager.h"
+
+void manager_etc_hosts_flush(Manager *m);
+int manager_etc_hosts_read(Manager *m);
+int manager_etc_hosts_lookup(Manager *m, DnsQuestion* q, DnsAnswer **answer);
diff --git a/src/grp-resolve/systemd-resolved/resolved-gperf.gperf b/src/grp-resolve/systemd-resolved/resolved-gperf.gperf
new file mode 100644
index 0000000000..6f8df3b533
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-gperf.gperf
@@ -0,0 +1,24 @@
+%{
+#include <stddef.h>
+
+#include "systemd-shared/conf-parser.h"
+
+#include "resolved-conf.h"
+%}
+struct ConfigPerfItem;
+%null_strings
+%language=ANSI-C
+%define slot-name section_and_lvalue
+%define hash-function-name resolved_gperf_hash
+%define lookup-function-name resolved_gperf_lookup
+%readonly-tables
+%omit-struct-type
+%struct-type
+%includes
+%%
+Resolve.DNS, config_parse_dns_servers, DNS_SERVER_SYSTEM, 0
+Resolve.FallbackDNS, config_parse_dns_servers, DNS_SERVER_FALLBACK, 0
+Resolve.Domains, config_parse_search_domains, 0, 0
+Resolve.LLMNR, config_parse_resolve_support, 0, offsetof(Manager, llmnr_support)
+Resolve.DNSSEC, config_parse_dnssec_mode, 0, offsetof(Manager, dnssec_mode)
+Resolve.Cache, config_parse_bool, 0, offsetof(Manager, enable_cache)
diff --git a/src/grp-resolve/systemd-resolved/resolved-link-bus.c b/src/grp-resolve/systemd-resolved/resolved-link-bus.c
new file mode 100644
index 0000000000..bea3c35829
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-link-bus.c
@@ -0,0 +1,630 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2016 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "sd-bus/bus-common-errors.h"
+#include "sd-bus/bus-util.h"
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/parse-util.h"
+#include "systemd-basic/strv.h"
+#include "systemd-shared/resolve-util.h"
+
+#include "resolved-bus.h"
+#include "resolved-link-bus.h"
+#include "resolved-resolv-conf.h"
+
+static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_resolve_support, resolve_support, ResolveSupport);
+
+static int property_get_dnssec_mode(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Link *l = userdata;
+
+ assert(reply);
+ assert(l);
+
+ return sd_bus_message_append(reply, "s", dnssec_mode_to_string(link_get_dnssec_mode(l)));
+}
+
+static int property_get_dns(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Link *l = userdata;
+ DnsServer *s;
+ int r;
+
+ assert(reply);
+ assert(l);
+
+ r = sd_bus_message_open_container(reply, 'a', "(iay)");
+ if (r < 0)
+ return r;
+
+ LIST_FOREACH(servers, s, l->dns_servers) {
+ r = bus_dns_server_append(reply, s, false);
+ if (r < 0)
+ return r;
+ }
+
+ return sd_bus_message_close_container(reply);
+}
+
+static int property_get_domains(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Link *l = userdata;
+ DnsSearchDomain *d;
+ int r;
+
+ assert(reply);
+ assert(l);
+
+ r = sd_bus_message_open_container(reply, 'a', "(sb)");
+ if (r < 0)
+ return r;
+
+ LIST_FOREACH(domains, d, l->search_domains) {
+ r = sd_bus_message_append(reply, "(sb)", d->name, d->route_only);
+ if (r < 0)
+ return r;
+ }
+
+ return sd_bus_message_close_container(reply);
+}
+
+static int property_get_scopes_mask(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Link *l = userdata;
+ uint64_t mask;
+
+ assert(reply);
+ assert(l);
+
+ mask = (l->unicast_scope ? SD_RESOLVED_DNS : 0) |
+ (l->llmnr_ipv4_scope ? SD_RESOLVED_LLMNR_IPV4 : 0) |
+ (l->llmnr_ipv6_scope ? SD_RESOLVED_LLMNR_IPV6 : 0) |
+ (l->mdns_ipv4_scope ? SD_RESOLVED_MDNS_IPV4 : 0) |
+ (l->mdns_ipv6_scope ? SD_RESOLVED_MDNS_IPV6 : 0);
+
+ return sd_bus_message_append(reply, "t", mask);
+}
+
+static int property_get_ntas(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Link *l = userdata;
+ const char *name;
+ Iterator i;
+ int r;
+
+ assert(reply);
+ assert(l);
+
+ r = sd_bus_message_open_container(reply, 'a', "s");
+ if (r < 0)
+ return r;
+
+ SET_FOREACH(name, l->dnssec_negative_trust_anchors, i) {
+ r = sd_bus_message_append(reply, "s", name);
+ if (r < 0)
+ return r;
+ }
+
+ return sd_bus_message_close_container(reply);
+}
+
+static int property_get_dnssec_supported(
+ sd_bus *bus,
+ const char *path,
+ const char *interface,
+ const char *property,
+ sd_bus_message *reply,
+ void *userdata,
+ sd_bus_error *error) {
+
+ Link *l = userdata;
+
+ assert(reply);
+ assert(l);
+
+ return sd_bus_message_append(reply, "b", link_dnssec_supported(l));
+}
+
+static int verify_unmanaged_link(Link *l, sd_bus_error *error) {
+ assert(l);
+
+ if (l->flags & IFF_LOOPBACK)
+ return sd_bus_error_setf(error, BUS_ERROR_LINK_BUSY, "Link %s is loopback device.", l->name);
+ if (l->is_managed)
+ return sd_bus_error_setf(error, BUS_ERROR_LINK_BUSY, "Link %s is managed.", l->name);
+
+ return 0;
+}
+
+int bus_link_method_set_dns_servers(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ _cleanup_free_ struct in_addr_data *dns = NULL;
+ size_t allocated = 0, n = 0;
+ Link *l = userdata;
+ unsigned i;
+ int r;
+
+ assert(message);
+ assert(l);
+
+ r = verify_unmanaged_link(l, error);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_enter_container(message, 'a', "(iay)");
+ if (r < 0)
+ return r;
+
+ for (;;) {
+ int family;
+ size_t sz;
+ const void *d;
+
+ assert_cc(sizeof(int) == sizeof(int32_t));
+
+ r = sd_bus_message_enter_container(message, 'r', "iay");
+ if (r < 0)
+ return r;
+ if (r == 0)
+ break;
+
+ r = sd_bus_message_read(message, "i", &family);
+ if (r < 0)
+ return r;
+
+ if (!IN_SET(family, AF_INET, AF_INET6))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Unknown address family %i", family);
+
+ r = sd_bus_message_read_array(message, 'y', &d, &sz);
+ if (r < 0)
+ return r;
+ if (sz != FAMILY_ADDRESS_SIZE(family))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid address size");
+
+ if (!dns_server_address_valid(family, d))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid DNS server address");
+
+ r = sd_bus_message_exit_container(message);
+ if (r < 0)
+ return r;
+
+ if (!GREEDY_REALLOC(dns, allocated, n+1))
+ return -ENOMEM;
+
+ dns[n].family = family;
+ memcpy(&dns[n].address, d, sz);
+ n++;
+ }
+
+ r = sd_bus_message_exit_container(message);
+ if (r < 0)
+ return r;
+
+ dns_server_mark_all(l->dns_servers);
+
+ for (i = 0; i < n; i++) {
+ DnsServer *s;
+
+ s = dns_server_find(l->dns_servers, dns[i].family, &dns[i].address, 0);
+ if (s)
+ dns_server_move_back_and_unmark(s);
+ else {
+ r = dns_server_new(l->manager, NULL, DNS_SERVER_LINK, l, dns[i].family, &dns[i].address, 0);
+ if (r < 0)
+ goto clear;
+ }
+
+ }
+
+ dns_server_unlink_marked(l->dns_servers);
+ link_allocate_scopes(l);
+
+ (void) link_save_user(l);
+ (void) manager_write_resolv_conf(l->manager);
+
+ return sd_bus_reply_method_return(message, NULL);
+
+clear:
+ dns_server_unlink_all(l->dns_servers);
+ return r;
+}
+
+int bus_link_method_set_domains(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ Link *l = userdata;
+ int r;
+
+ assert(message);
+ assert(l);
+
+ r = verify_unmanaged_link(l, error);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_enter_container(message, 'a', "(sb)");
+ if (r < 0)
+ return r;
+
+ for (;;) {
+ const char *name;
+ int route_only;
+
+ r = sd_bus_message_read(message, "(sb)", &name, &route_only);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ break;
+
+ r = dns_name_is_valid(name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid search domain %s", name);
+ if (!route_only && dns_name_is_root(name))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Root domain is not suitable as search domain");
+ }
+
+ dns_search_domain_mark_all(l->search_domains);
+
+ r = sd_bus_message_rewind(message, false);
+ if (r < 0)
+ return r;
+
+ for (;;) {
+ DnsSearchDomain *d;
+ const char *name;
+ int route_only;
+
+ r = sd_bus_message_read(message, "(sb)", &name, &route_only);
+ if (r < 0)
+ goto clear;
+ if (r == 0)
+ break;
+
+ r = dns_search_domain_find(l->search_domains, name, &d);
+ if (r < 0)
+ goto clear;
+
+ if (r > 0)
+ dns_search_domain_move_back_and_unmark(d);
+ else {
+ r = dns_search_domain_new(l->manager, &d, DNS_SEARCH_DOMAIN_LINK, l, name);
+ if (r < 0)
+ goto clear;
+ }
+
+ d->route_only = route_only;
+ }
+
+ r = sd_bus_message_exit_container(message);
+ if (r < 0)
+ goto clear;
+
+ dns_search_domain_unlink_marked(l->search_domains);
+
+ (void) link_save_user(l);
+ (void) manager_write_resolv_conf(l->manager);
+
+ return sd_bus_reply_method_return(message, NULL);
+
+clear:
+ dns_search_domain_unlink_all(l->search_domains);
+ return r;
+}
+
+int bus_link_method_set_llmnr(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ Link *l = userdata;
+ ResolveSupport mode;
+ const char *llmnr;
+ int r;
+
+ assert(message);
+ assert(l);
+
+ r = verify_unmanaged_link(l, error);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_read(message, "s", &llmnr);
+ if (r < 0)
+ return r;
+
+ if (isempty(llmnr))
+ mode = RESOLVE_SUPPORT_YES;
+ else {
+ mode = resolve_support_from_string(llmnr);
+ if (mode < 0)
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid LLMNR setting: %s", llmnr);
+ }
+
+ l->llmnr_support = mode;
+ link_allocate_scopes(l);
+ link_add_rrs(l, false);
+
+ (void) link_save_user(l);
+
+ return sd_bus_reply_method_return(message, NULL);
+}
+
+int bus_link_method_set_mdns(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ Link *l = userdata;
+ ResolveSupport mode;
+ const char *mdns;
+ int r;
+
+ assert(message);
+ assert(l);
+
+ r = verify_unmanaged_link(l, error);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_read(message, "s", &mdns);
+ if (r < 0)
+ return r;
+
+ if (isempty(mdns))
+ mode = RESOLVE_SUPPORT_NO;
+ else {
+ mode = resolve_support_from_string(mdns);
+ if (mode < 0)
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid MulticastDNS setting: %s", mdns);
+ }
+
+ l->mdns_support = mode;
+ link_allocate_scopes(l);
+ link_add_rrs(l, false);
+
+ (void) link_save_user(l);
+
+ return sd_bus_reply_method_return(message, NULL);
+}
+
+int bus_link_method_set_dnssec(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ Link *l = userdata;
+ const char *dnssec;
+ DnssecMode mode;
+ int r;
+
+ assert(message);
+ assert(l);
+
+ r = verify_unmanaged_link(l, error);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_read(message, "s", &dnssec);
+ if (r < 0)
+ return r;
+
+ if (isempty(dnssec))
+ mode = _DNSSEC_MODE_INVALID;
+ else {
+ mode = dnssec_mode_from_string(dnssec);
+ if (mode < 0)
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid DNSSEC setting: %s", dnssec);
+ }
+
+ link_set_dnssec_mode(l, mode);
+
+ (void) link_save_user(l);
+
+ return sd_bus_reply_method_return(message, NULL);
+}
+
+int bus_link_method_set_dnssec_negative_trust_anchors(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ _cleanup_set_free_free_ Set *ns = NULL;
+ _cleanup_free_ char **ntas = NULL;
+ Link *l = userdata;
+ int r;
+ char **i;
+
+ assert(message);
+ assert(l);
+
+ r = verify_unmanaged_link(l, error);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_read_strv(message, &ntas);
+ if (r < 0)
+ return r;
+
+ STRV_FOREACH(i, ntas) {
+ r = dns_name_is_valid(*i);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid negative trust anchor domain: %s", *i);
+ }
+
+ ns = set_new(&dns_name_hash_ops);
+ if (!ns)
+ return -ENOMEM;
+
+ STRV_FOREACH(i, ntas) {
+ r = set_put_strdup(ns, *i);
+ if (r < 0)
+ return r;
+ }
+
+ set_free_free(l->dnssec_negative_trust_anchors);
+ l->dnssec_negative_trust_anchors = ns;
+ ns = NULL;
+
+ (void) link_save_user(l);
+
+ return sd_bus_reply_method_return(message, NULL);
+}
+
+int bus_link_method_revert(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+ Link *l = userdata;
+ int r;
+
+ assert(message);
+ assert(l);
+
+ r = verify_unmanaged_link(l, error);
+ if (r < 0)
+ return r;
+
+ link_flush_settings(l);
+ link_allocate_scopes(l);
+ link_add_rrs(l, false);
+
+ (void) link_save_user(l);
+ (void) manager_write_resolv_conf(l->manager);
+
+ return sd_bus_reply_method_return(message, NULL);
+}
+
+const sd_bus_vtable link_vtable[] = {
+ SD_BUS_VTABLE_START(0),
+
+ SD_BUS_PROPERTY("ScopesMask", "t", property_get_scopes_mask, 0, 0),
+ SD_BUS_PROPERTY("DNS", "a(iay)", property_get_dns, 0, 0),
+ SD_BUS_PROPERTY("Domains", "a(sb)", property_get_domains, 0, 0),
+ SD_BUS_PROPERTY("LLMNR", "s", property_get_resolve_support, offsetof(Link, llmnr_support), 0),
+ SD_BUS_PROPERTY("MulticastDNS", "s", property_get_resolve_support, offsetof(Link, mdns_support), 0),
+ SD_BUS_PROPERTY("DNSSEC", "s", property_get_dnssec_mode, 0, 0),
+ SD_BUS_PROPERTY("DNSSECNegativeTrustAnchors", "as", property_get_ntas, 0, 0),
+ SD_BUS_PROPERTY("DNSSECSupported", "b", property_get_dnssec_supported, 0, 0),
+
+ SD_BUS_METHOD("SetDNS", "a(iay)", NULL, bus_link_method_set_dns_servers, 0),
+ SD_BUS_METHOD("SetDomains", "a(sb)", NULL, bus_link_method_set_domains, 0),
+ SD_BUS_METHOD("SetLLMNR", "s", NULL, bus_link_method_set_llmnr, 0),
+ SD_BUS_METHOD("SetMulticastDNS", "s", NULL, bus_link_method_set_mdns, 0),
+ SD_BUS_METHOD("SetDNSSEC", "s", NULL, bus_link_method_set_dnssec, 0),
+ SD_BUS_METHOD("SetDNSSECNegativeTrustAnchors", "as", NULL, bus_link_method_set_dnssec_negative_trust_anchors, 0),
+ SD_BUS_METHOD("Revert", NULL, NULL, bus_link_method_revert, 0),
+
+ SD_BUS_VTABLE_END
+};
+
+int link_object_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
+ _cleanup_free_ char *e = NULL;
+ Manager *m = userdata;
+ int ifindex;
+ Link *link;
+ int r;
+
+ assert(bus);
+ assert(path);
+ assert(interface);
+ assert(found);
+ assert(m);
+
+ r = sd_bus_path_decode(path, "/org/freedesktop/resolve1/link", &e);
+ if (r <= 0)
+ return 0;
+
+ r = parse_ifindex(e, &ifindex);
+ if (r < 0)
+ return 0;
+
+ link = hashmap_get(m->links, INT_TO_PTR(ifindex));
+ if (!link)
+ return 0;
+
+ *found = link;
+ return 1;
+}
+
+char *link_bus_path(Link *link) {
+ _cleanup_free_ char *ifindex = NULL;
+ char *p;
+ int r;
+
+ assert(link);
+
+ if (asprintf(&ifindex, "%i", link->ifindex) < 0)
+ return NULL;
+
+ r = sd_bus_path_encode("/org/freedesktop/resolve1/link", ifindex, &p);
+ if (r < 0)
+ return NULL;
+
+ return p;
+}
+
+int link_node_enumerator(sd_bus *bus, const char *path, void *userdata, char ***nodes, sd_bus_error *error) {
+ _cleanup_strv_free_ char **l = NULL;
+ Manager *m = userdata;
+ Link *link;
+ Iterator i;
+ unsigned c = 0;
+
+ assert(bus);
+ assert(path);
+ assert(m);
+ assert(nodes);
+
+ l = new0(char*, hashmap_size(m->links) + 1);
+ if (!l)
+ return -ENOMEM;
+
+ HASHMAP_FOREACH(link, m->links, i) {
+ char *p;
+
+ p = link_bus_path(link);
+ if (!p)
+ return -ENOMEM;
+
+ l[c++] = p;
+ }
+
+ l[c] = NULL;
+ *nodes = l;
+ l = NULL;
+
+ return 1;
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-link-bus.h b/src/grp-resolve/systemd-resolved/resolved-link-bus.h
new file mode 100644
index 0000000000..b1ac57961d
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-link-bus.h
@@ -0,0 +1,38 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2016 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <systemd/sd-bus.h>
+
+#include "resolved-link.h"
+
+extern const sd_bus_vtable link_vtable[];
+
+int link_object_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error);
+char *link_bus_path(Link *link);
+int link_node_enumerator(sd_bus *bus, const char *path, void *userdata, char ***nodes, sd_bus_error *error);
+
+int bus_link_method_set_dns_servers(sd_bus_message *message, void *userdata, sd_bus_error *error);
+int bus_link_method_set_domains(sd_bus_message *message, void *userdata, sd_bus_error *error);
+int bus_link_method_set_llmnr(sd_bus_message *message, void *userdata, sd_bus_error *error);
+int bus_link_method_set_mdns(sd_bus_message *message, void *userdata, sd_bus_error *error);
+int bus_link_method_set_dnssec(sd_bus_message *message, void *userdata, sd_bus_error *error);
+int bus_link_method_set_dnssec_negative_trust_anchors(sd_bus_message *message, void *userdata, sd_bus_error *error);
+int bus_link_method_revert(sd_bus_message *message, void *userdata, sd_bus_error *error);
diff --git a/src/grp-resolve/systemd-resolved/resolved-link.c b/src/grp-resolve/systemd-resolved/resolved-link.c
new file mode 100644
index 0000000000..ccfcc70d1a
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-link.c
@@ -0,0 +1,1115 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <net/if.h>
+
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/fd-util.h"
+#include "systemd-basic/fileio.h"
+#include "systemd-basic/missing.h"
+#include "systemd-basic/mkdir.h"
+#include "systemd-basic/parse-util.h"
+#include "systemd-basic/string-util.h"
+#include "systemd-basic/strv.h"
+#include "systemd-staging/sd-network.h"
+
+#include "resolved-link.h"
+
+int link_new(Manager *m, Link **ret, int ifindex) {
+ _cleanup_(link_freep) Link *l = NULL;
+ int r;
+
+ assert(m);
+ assert(ifindex > 0);
+
+ r = hashmap_ensure_allocated(&m->links, NULL);
+ if (r < 0)
+ return r;
+
+ l = new0(Link, 1);
+ if (!l)
+ return -ENOMEM;
+
+ l->ifindex = ifindex;
+ l->llmnr_support = RESOLVE_SUPPORT_YES;
+ l->mdns_support = RESOLVE_SUPPORT_NO;
+ l->dnssec_mode = _DNSSEC_MODE_INVALID;
+ l->operstate = IF_OPER_UNKNOWN;
+
+ if (asprintf(&l->state_file, "/run/systemd/resolve/netif/%i", ifindex) < 0)
+ return -ENOMEM;
+
+ r = hashmap_put(m->links, INT_TO_PTR(ifindex), l);
+ if (r < 0)
+ return r;
+
+ l->manager = m;
+
+ if (ret)
+ *ret = l;
+ l = NULL;
+
+ return 0;
+}
+
+void link_flush_settings(Link *l) {
+ assert(l);
+
+ l->llmnr_support = RESOLVE_SUPPORT_YES;
+ l->mdns_support = RESOLVE_SUPPORT_NO;
+ l->dnssec_mode = _DNSSEC_MODE_INVALID;
+
+ dns_server_unlink_all(l->dns_servers);
+ dns_search_domain_unlink_all(l->search_domains);
+
+ l->dnssec_negative_trust_anchors = set_free_free(l->dnssec_negative_trust_anchors);
+}
+
+Link *link_free(Link *l) {
+ if (!l)
+ return NULL;
+
+ link_flush_settings(l);
+
+ while (l->addresses)
+ (void) link_address_free(l->addresses);
+
+ if (l->manager)
+ hashmap_remove(l->manager->links, INT_TO_PTR(l->ifindex));
+
+ dns_scope_free(l->unicast_scope);
+ dns_scope_free(l->llmnr_ipv4_scope);
+ dns_scope_free(l->llmnr_ipv6_scope);
+ dns_scope_free(l->mdns_ipv4_scope);
+ dns_scope_free(l->mdns_ipv6_scope);
+
+ free(l->state_file);
+
+ free(l);
+ return NULL;
+}
+
+void link_allocate_scopes(Link *l) {
+ int r;
+
+ assert(l);
+
+ if (link_relevant(l, AF_UNSPEC, false) &&
+ l->dns_servers) {
+ if (!l->unicast_scope) {
+ r = dns_scope_new(l->manager, &l->unicast_scope, l, DNS_PROTOCOL_DNS, AF_UNSPEC);
+ if (r < 0)
+ log_warning_errno(r, "Failed to allocate DNS scope: %m");
+ }
+ } else
+ l->unicast_scope = dns_scope_free(l->unicast_scope);
+
+ if (link_relevant(l, AF_INET, true) &&
+ l->llmnr_support != RESOLVE_SUPPORT_NO &&
+ l->manager->llmnr_support != RESOLVE_SUPPORT_NO) {
+ if (!l->llmnr_ipv4_scope) {
+ r = dns_scope_new(l->manager, &l->llmnr_ipv4_scope, l, DNS_PROTOCOL_LLMNR, AF_INET);
+ if (r < 0)
+ log_warning_errno(r, "Failed to allocate LLMNR IPv4 scope: %m");
+ }
+ } else
+ l->llmnr_ipv4_scope = dns_scope_free(l->llmnr_ipv4_scope);
+
+ if (link_relevant(l, AF_INET6, true) &&
+ l->llmnr_support != RESOLVE_SUPPORT_NO &&
+ l->manager->llmnr_support != RESOLVE_SUPPORT_NO &&
+ socket_ipv6_is_supported()) {
+ if (!l->llmnr_ipv6_scope) {
+ r = dns_scope_new(l->manager, &l->llmnr_ipv6_scope, l, DNS_PROTOCOL_LLMNR, AF_INET6);
+ if (r < 0)
+ log_warning_errno(r, "Failed to allocate LLMNR IPv6 scope: %m");
+ }
+ } else
+ l->llmnr_ipv6_scope = dns_scope_free(l->llmnr_ipv6_scope);
+
+ if (link_relevant(l, AF_INET, true) &&
+ l->mdns_support != RESOLVE_SUPPORT_NO &&
+ l->manager->mdns_support != RESOLVE_SUPPORT_NO) {
+ if (!l->mdns_ipv4_scope) {
+ r = dns_scope_new(l->manager, &l->mdns_ipv4_scope, l, DNS_PROTOCOL_MDNS, AF_INET);
+ if (r < 0)
+ log_warning_errno(r, "Failed to allocate mDNS IPv4 scope: %m");
+ }
+ } else
+ l->mdns_ipv4_scope = dns_scope_free(l->mdns_ipv4_scope);
+
+ if (link_relevant(l, AF_INET6, true) &&
+ l->mdns_support != RESOLVE_SUPPORT_NO &&
+ l->manager->mdns_support != RESOLVE_SUPPORT_NO) {
+ if (!l->mdns_ipv6_scope) {
+ r = dns_scope_new(l->manager, &l->mdns_ipv6_scope, l, DNS_PROTOCOL_MDNS, AF_INET6);
+ if (r < 0)
+ log_warning_errno(r, "Failed to allocate mDNS IPv6 scope: %m");
+ }
+ } else
+ l->mdns_ipv6_scope = dns_scope_free(l->mdns_ipv6_scope);
+}
+
+void link_add_rrs(Link *l, bool force_remove) {
+ LinkAddress *a;
+
+ LIST_FOREACH(addresses, a, l->addresses)
+ link_address_add_rrs(a, force_remove);
+}
+
+int link_process_rtnl(Link *l, sd_netlink_message *m) {
+ const char *n = NULL;
+ int r;
+
+ assert(l);
+ assert(m);
+
+ r = sd_rtnl_message_link_get_flags(m, &l->flags);
+ if (r < 0)
+ return r;
+
+ (void) sd_netlink_message_read_u32(m, IFLA_MTU, &l->mtu);
+ (void) sd_netlink_message_read_u8(m, IFLA_OPERSTATE, &l->operstate);
+
+ if (sd_netlink_message_read_string(m, IFLA_IFNAME, &n) >= 0) {
+ strncpy(l->name, n, sizeof(l->name)-1);
+ char_array_0(l->name);
+ }
+
+ link_allocate_scopes(l);
+ link_add_rrs(l, false);
+
+ return 0;
+}
+
+static int link_update_dns_server_one(Link *l, const char *name) {
+ union in_addr_union a;
+ DnsServer *s;
+ int family, r;
+
+ assert(l);
+ assert(name);
+
+ r = in_addr_from_string_auto(name, &family, &a);
+ if (r < 0)
+ return r;
+
+ s = dns_server_find(l->dns_servers, family, &a, 0);
+ if (s) {
+ dns_server_move_back_and_unmark(s);
+ return 0;
+ }
+
+ return dns_server_new(l->manager, NULL, DNS_SERVER_LINK, l, family, &a, 0);
+}
+
+static int link_update_dns_servers(Link *l) {
+ _cleanup_strv_free_ char **nameservers = NULL;
+ char **nameserver;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_dns(l->ifindex, &nameservers);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ dns_server_mark_all(l->dns_servers);
+
+ STRV_FOREACH(nameserver, nameservers) {
+ r = link_update_dns_server_one(l, *nameserver);
+ if (r < 0)
+ goto clear;
+ }
+
+ dns_server_unlink_marked(l->dns_servers);
+ return 0;
+
+clear:
+ dns_server_unlink_all(l->dns_servers);
+ return r;
+}
+
+static int link_update_llmnr_support(Link *l) {
+ _cleanup_free_ char *b = NULL;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_llmnr(l->ifindex, &b);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ l->llmnr_support = resolve_support_from_string(b);
+ if (l->llmnr_support < 0) {
+ r = -EINVAL;
+ goto clear;
+ }
+
+ return 0;
+
+clear:
+ l->llmnr_support = RESOLVE_SUPPORT_YES;
+ return r;
+}
+
+static int link_update_mdns_support(Link *l) {
+ _cleanup_free_ char *b = NULL;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_mdns(l->ifindex, &b);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ l->mdns_support = resolve_support_from_string(b);
+ if (l->mdns_support < 0) {
+ r = -EINVAL;
+ goto clear;
+ }
+
+ return 0;
+
+clear:
+ l->mdns_support = RESOLVE_SUPPORT_NO;
+ return r;
+}
+
+void link_set_dnssec_mode(Link *l, DnssecMode mode) {
+
+ assert(l);
+
+ if (l->dnssec_mode == mode)
+ return;
+
+ if ((l->dnssec_mode == _DNSSEC_MODE_INVALID) ||
+ (l->dnssec_mode == DNSSEC_NO && mode != DNSSEC_NO) ||
+ (l->dnssec_mode == DNSSEC_ALLOW_DOWNGRADE && mode == DNSSEC_YES)) {
+
+ /* When switching from non-DNSSEC mode to DNSSEC mode, flush the cache. Also when switching from the
+ * allow-downgrade mode to full DNSSEC mode, flush it too. */
+ if (l->unicast_scope)
+ dns_cache_flush(&l->unicast_scope->cache);
+ }
+
+ l->dnssec_mode = mode;
+}
+
+static int link_update_dnssec_mode(Link *l) {
+ _cleanup_free_ char *m = NULL;
+ DnssecMode mode;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_dnssec(l->ifindex, &m);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ mode = dnssec_mode_from_string(m);
+ if (mode < 0) {
+ r = -EINVAL;
+ goto clear;
+ }
+
+ link_set_dnssec_mode(l, mode);
+
+ return 0;
+
+clear:
+ l->dnssec_mode = _DNSSEC_MODE_INVALID;
+ return r;
+}
+
+static int link_update_dnssec_negative_trust_anchors(Link *l) {
+ _cleanup_strv_free_ char **ntas = NULL;
+ _cleanup_set_free_free_ Set *ns = NULL;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_dnssec_negative_trust_anchors(l->ifindex, &ntas);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ ns = set_new(&dns_name_hash_ops);
+ if (!ns)
+ return -ENOMEM;
+
+ r = set_put_strdupv(ns, ntas);
+ if (r < 0)
+ return r;
+
+ set_free_free(l->dnssec_negative_trust_anchors);
+ l->dnssec_negative_trust_anchors = ns;
+ ns = NULL;
+
+ return 0;
+
+clear:
+ l->dnssec_negative_trust_anchors = set_free_free(l->dnssec_negative_trust_anchors);
+ return r;
+}
+
+static int link_update_search_domain_one(Link *l, const char *name, bool route_only) {
+ DnsSearchDomain *d;
+ int r;
+
+ assert(l);
+ assert(name);
+
+ r = dns_search_domain_find(l->search_domains, name, &d);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ dns_search_domain_move_back_and_unmark(d);
+ else {
+ r = dns_search_domain_new(l->manager, &d, DNS_SEARCH_DOMAIN_LINK, l, name);
+ if (r < 0)
+ return r;
+ }
+
+ d->route_only = route_only;
+ return 0;
+}
+
+static int link_update_search_domains(Link *l) {
+ _cleanup_strv_free_ char **sdomains = NULL, **rdomains = NULL;
+ char **i;
+ int r, q;
+
+ assert(l);
+
+ r = sd_network_link_get_search_domains(l->ifindex, &sdomains);
+ if (r < 0 && r != -ENODATA)
+ goto clear;
+
+ q = sd_network_link_get_route_domains(l->ifindex, &rdomains);
+ if (q < 0 && q != -ENODATA) {
+ r = q;
+ goto clear;
+ }
+
+ if (r == -ENODATA && q == -ENODATA) {
+ /* networkd knows nothing about this interface, and that's fine. */
+ r = 0;
+ goto clear;
+ }
+
+ dns_search_domain_mark_all(l->search_domains);
+
+ STRV_FOREACH(i, sdomains) {
+ r = link_update_search_domain_one(l, *i, false);
+ if (r < 0)
+ goto clear;
+ }
+
+ STRV_FOREACH(i, rdomains) {
+ r = link_update_search_domain_one(l, *i, true);
+ if (r < 0)
+ goto clear;
+ }
+
+ dns_search_domain_unlink_marked(l->search_domains);
+ return 0;
+
+clear:
+ dns_search_domain_unlink_all(l->search_domains);
+ return r;
+}
+
+static int link_is_managed(Link *l) {
+ _cleanup_free_ char *state = NULL;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_setup_state(l->ifindex, &state);
+ if (r == -ENODATA)
+ return 0;
+ if (r < 0)
+ return r;
+
+ return !STR_IN_SET(state, "pending", "unmanaged");
+}
+
+static void link_read_settings(Link *l) {
+ int r;
+
+ assert(l);
+
+ /* Read settings from networkd, except when networkd is not managing this interface. */
+
+ r = link_is_managed(l);
+ if (r < 0) {
+ log_warning_errno(r, "Failed to determine whether interface %s is managed: %m", l->name);
+ return;
+ }
+ if (r == 0) {
+
+ /* If this link used to be managed, but is now unmanaged, flush all our settings — but only once. */
+ if (l->is_managed)
+ link_flush_settings(l);
+
+ l->is_managed = false;
+ return;
+ }
+
+ l->is_managed = true;
+
+ r = link_update_dns_servers(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read DNS servers for interface %s, ignoring: %m", l->name);
+
+ r = link_update_llmnr_support(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read LLMNR support for interface %s, ignoring: %m", l->name);
+
+ r = link_update_mdns_support(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read mDNS support for interface %s, ignoring: %m", l->name);
+
+ r = link_update_dnssec_mode(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read DNSSEC mode for interface %s, ignoring: %m", l->name);
+
+ r = link_update_dnssec_negative_trust_anchors(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read DNSSEC negative trust anchors for interface %s, ignoring: %m", l->name);
+
+ r = link_update_search_domains(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read search domains for interface %s, ignoring: %m", l->name);
+}
+
+int link_update(Link *l) {
+ assert(l);
+
+ link_read_settings(l);
+ link_load_user(l);
+ link_allocate_scopes(l);
+ link_add_rrs(l, false);
+
+ return 0;
+}
+
+bool link_relevant(Link *l, int family, bool local_multicast) {
+ _cleanup_free_ char *state = NULL;
+ LinkAddress *a;
+
+ assert(l);
+
+ /* A link is relevant for local multicast traffic if it isn't a loopback or pointopoint device, has a link
+ * beat, can do multicast and has at least one link-local (or better) IP address.
+ *
+ * A link is relevant for non-multicast traffic if it isn't a loopback device, has a link beat, and has at
+ * least one routable address.*/
+
+ if (l->flags & (IFF_LOOPBACK|IFF_DORMANT))
+ return false;
+
+ if ((l->flags & (IFF_UP|IFF_LOWER_UP)) != (IFF_UP|IFF_LOWER_UP))
+ return false;
+
+ if (local_multicast) {
+ if (l->flags & IFF_POINTOPOINT)
+ return false;
+
+ if ((l->flags & IFF_MULTICAST) != IFF_MULTICAST)
+ return false;
+ }
+
+ /* Check kernel operstate
+ * https://www.kernel.org/doc/Documentation/networking/operstates.txt */
+ if (!IN_SET(l->operstate, IF_OPER_UNKNOWN, IF_OPER_UP))
+ return false;
+
+ (void) sd_network_link_get_operational_state(l->ifindex, &state);
+ if (state && !STR_IN_SET(state, "unknown", "degraded", "routable"))
+ return false;
+
+ LIST_FOREACH(addresses, a, l->addresses)
+ if ((family == AF_UNSPEC || a->family == family) && link_address_relevant(a, local_multicast))
+ return true;
+
+ return false;
+}
+
+LinkAddress *link_find_address(Link *l, int family, const union in_addr_union *in_addr) {
+ LinkAddress *a;
+
+ assert(l);
+
+ LIST_FOREACH(addresses, a, l->addresses)
+ if (a->family == family && in_addr_equal(family, &a->in_addr, in_addr))
+ return a;
+
+ return NULL;
+}
+
+DnsServer* link_set_dns_server(Link *l, DnsServer *s) {
+ assert(l);
+
+ if (l->current_dns_server == s)
+ return s;
+
+ if (s)
+ log_info("Switching to DNS server %s for interface %s.", dns_server_string(s), l->name);
+
+ dns_server_unref(l->current_dns_server);
+ l->current_dns_server = dns_server_ref(s);
+
+ if (l->unicast_scope)
+ dns_cache_flush(&l->unicast_scope->cache);
+
+ return s;
+}
+
+DnsServer *link_get_dns_server(Link *l) {
+ assert(l);
+
+ if (!l->current_dns_server)
+ link_set_dns_server(l, l->dns_servers);
+
+ return l->current_dns_server;
+}
+
+void link_next_dns_server(Link *l) {
+ assert(l);
+
+ if (!l->current_dns_server)
+ return;
+
+ /* Change to the next one, but make sure to follow the linked
+ * list only if this server is actually still linked. */
+ if (l->current_dns_server->linked && l->current_dns_server->servers_next) {
+ link_set_dns_server(l, l->current_dns_server->servers_next);
+ return;
+ }
+
+ link_set_dns_server(l, l->dns_servers);
+}
+
+DnssecMode link_get_dnssec_mode(Link *l) {
+ assert(l);
+
+ if (l->dnssec_mode != _DNSSEC_MODE_INVALID)
+ return l->dnssec_mode;
+
+ return manager_get_dnssec_mode(l->manager);
+}
+
+bool link_dnssec_supported(Link *l) {
+ DnsServer *server;
+
+ assert(l);
+
+ if (link_get_dnssec_mode(l) == DNSSEC_NO)
+ return false;
+
+ server = link_get_dns_server(l);
+ if (server)
+ return dns_server_dnssec_supported(server);
+
+ return true;
+}
+
+int link_address_new(Link *l, LinkAddress **ret, int family, const union in_addr_union *in_addr) {
+ LinkAddress *a;
+
+ assert(l);
+ assert(in_addr);
+
+ a = new0(LinkAddress, 1);
+ if (!a)
+ return -ENOMEM;
+
+ a->family = family;
+ a->in_addr = *in_addr;
+
+ a->link = l;
+ LIST_PREPEND(addresses, l->addresses, a);
+
+ if (ret)
+ *ret = a;
+
+ return 0;
+}
+
+LinkAddress *link_address_free(LinkAddress *a) {
+ if (!a)
+ return NULL;
+
+ if (a->link) {
+ LIST_REMOVE(addresses, a->link->addresses, a);
+
+ if (a->llmnr_address_rr) {
+ if (a->family == AF_INET && a->link->llmnr_ipv4_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_address_rr);
+ else if (a->family == AF_INET6 && a->link->llmnr_ipv6_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_address_rr);
+ }
+
+ if (a->llmnr_ptr_rr) {
+ if (a->family == AF_INET && a->link->llmnr_ipv4_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_ptr_rr);
+ else if (a->family == AF_INET6 && a->link->llmnr_ipv6_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_ptr_rr);
+ }
+ }
+
+ dns_resource_record_unref(a->llmnr_address_rr);
+ dns_resource_record_unref(a->llmnr_ptr_rr);
+
+ free(a);
+ return NULL;
+}
+
+void link_address_add_rrs(LinkAddress *a, bool force_remove) {
+ int r;
+
+ assert(a);
+
+ if (a->family == AF_INET) {
+
+ if (!force_remove &&
+ link_address_relevant(a, true) &&
+ a->link->llmnr_ipv4_scope &&
+ a->link->llmnr_support == RESOLVE_SUPPORT_YES &&
+ a->link->manager->llmnr_support == RESOLVE_SUPPORT_YES) {
+
+ if (!a->link->manager->llmnr_host_ipv4_key) {
+ a->link->manager->llmnr_host_ipv4_key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, a->link->manager->llmnr_hostname);
+ if (!a->link->manager->llmnr_host_ipv4_key) {
+ r = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ if (!a->llmnr_address_rr) {
+ a->llmnr_address_rr = dns_resource_record_new(a->link->manager->llmnr_host_ipv4_key);
+ if (!a->llmnr_address_rr) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ a->llmnr_address_rr->a.in_addr = a->in_addr.in;
+ a->llmnr_address_rr->ttl = LLMNR_DEFAULT_TTL;
+ }
+
+ if (!a->llmnr_ptr_rr) {
+ r = dns_resource_record_new_reverse(&a->llmnr_ptr_rr, a->family, &a->in_addr, a->link->manager->llmnr_hostname);
+ if (r < 0)
+ goto fail;
+
+ a->llmnr_ptr_rr->ttl = LLMNR_DEFAULT_TTL;
+ }
+
+ r = dns_zone_put(&a->link->llmnr_ipv4_scope->zone, a->link->llmnr_ipv4_scope, a->llmnr_address_rr, true);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add A record to LLMNR zone: %m");
+
+ r = dns_zone_put(&a->link->llmnr_ipv4_scope->zone, a->link->llmnr_ipv4_scope, a->llmnr_ptr_rr, false);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add IPv6 PTR record to LLMNR zone: %m");
+ } else {
+ if (a->llmnr_address_rr) {
+ if (a->link->llmnr_ipv4_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_address_rr);
+ a->llmnr_address_rr = dns_resource_record_unref(a->llmnr_address_rr);
+ }
+
+ if (a->llmnr_ptr_rr) {
+ if (a->link->llmnr_ipv4_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_ptr_rr);
+ a->llmnr_ptr_rr = dns_resource_record_unref(a->llmnr_ptr_rr);
+ }
+ }
+ }
+
+ if (a->family == AF_INET6) {
+
+ if (!force_remove &&
+ link_address_relevant(a, true) &&
+ a->link->llmnr_ipv6_scope &&
+ a->link->llmnr_support == RESOLVE_SUPPORT_YES &&
+ a->link->manager->llmnr_support == RESOLVE_SUPPORT_YES) {
+
+ if (!a->link->manager->llmnr_host_ipv6_key) {
+ a->link->manager->llmnr_host_ipv6_key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, a->link->manager->llmnr_hostname);
+ if (!a->link->manager->llmnr_host_ipv6_key) {
+ r = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ if (!a->llmnr_address_rr) {
+ a->llmnr_address_rr = dns_resource_record_new(a->link->manager->llmnr_host_ipv6_key);
+ if (!a->llmnr_address_rr) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ a->llmnr_address_rr->aaaa.in6_addr = a->in_addr.in6;
+ a->llmnr_address_rr->ttl = LLMNR_DEFAULT_TTL;
+ }
+
+ if (!a->llmnr_ptr_rr) {
+ r = dns_resource_record_new_reverse(&a->llmnr_ptr_rr, a->family, &a->in_addr, a->link->manager->llmnr_hostname);
+ if (r < 0)
+ goto fail;
+
+ a->llmnr_ptr_rr->ttl = LLMNR_DEFAULT_TTL;
+ }
+
+ r = dns_zone_put(&a->link->llmnr_ipv6_scope->zone, a->link->llmnr_ipv6_scope, a->llmnr_address_rr, true);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add AAAA record to LLMNR zone: %m");
+
+ r = dns_zone_put(&a->link->llmnr_ipv6_scope->zone, a->link->llmnr_ipv6_scope, a->llmnr_ptr_rr, false);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add IPv6 PTR record to LLMNR zone: %m");
+ } else {
+ if (a->llmnr_address_rr) {
+ if (a->link->llmnr_ipv6_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_address_rr);
+ a->llmnr_address_rr = dns_resource_record_unref(a->llmnr_address_rr);
+ }
+
+ if (a->llmnr_ptr_rr) {
+ if (a->link->llmnr_ipv6_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_ptr_rr);
+ a->llmnr_ptr_rr = dns_resource_record_unref(a->llmnr_ptr_rr);
+ }
+ }
+ }
+
+ return;
+
+fail:
+ log_debug_errno(r, "Failed to update address RRs: %m");
+}
+
+int link_address_update_rtnl(LinkAddress *a, sd_netlink_message *m) {
+ int r;
+ assert(a);
+ assert(m);
+
+ r = sd_rtnl_message_addr_get_flags(m, &a->flags);
+ if (r < 0)
+ return r;
+
+ sd_rtnl_message_addr_get_scope(m, &a->scope);
+
+ link_allocate_scopes(a->link);
+ link_add_rrs(a->link, false);
+
+ return 0;
+}
+
+bool link_address_relevant(LinkAddress *a, bool local_multicast) {
+ assert(a);
+
+ if (a->flags & (IFA_F_DEPRECATED|IFA_F_TENTATIVE))
+ return false;
+
+ if (a->scope >= (local_multicast ? RT_SCOPE_HOST : RT_SCOPE_LINK))
+ return false;
+
+ return true;
+}
+
+static bool link_needs_save(Link *l) {
+ assert(l);
+
+ /* Returns true if any of the settings where set different from the default */
+
+ if (l->is_managed)
+ return false;
+
+ if (l->llmnr_support != RESOLVE_SUPPORT_YES ||
+ l->mdns_support != RESOLVE_SUPPORT_NO ||
+ l->dnssec_mode != _DNSSEC_MODE_INVALID)
+ return true;
+
+ if (l->dns_servers ||
+ l->search_domains)
+ return true;
+
+ if (!set_isempty(l->dnssec_negative_trust_anchors))
+ return true;
+
+ return false;
+}
+
+int link_save_user(Link *l) {
+ _cleanup_free_ char *temp_path = NULL;
+ _cleanup_fclose_ FILE *f = NULL;
+ const char *v;
+ int r;
+
+ assert(l);
+ assert(l->state_file);
+
+ if (!link_needs_save(l)) {
+ (void) unlink(l->state_file);
+ return 0;
+ }
+
+ r = mkdir_parents(l->state_file, 0700);
+ if (r < 0)
+ goto fail;
+
+ r = fopen_temporary(l->state_file, &f, &temp_path);
+ if (r < 0)
+ goto fail;
+
+ fputs("# This is private data. Do not parse.\n", f);
+
+ v = resolve_support_to_string(l->llmnr_support);
+ if (v)
+ fprintf(f, "LLMNR=%s\n", v);
+
+ v = resolve_support_to_string(l->mdns_support);
+ if (v)
+ fprintf(f, "MDNS=%s\n", v);
+
+ v = dnssec_mode_to_string(l->dnssec_mode);
+ if (v)
+ fprintf(f, "DNSSEC=%s\n", v);
+
+ if (l->dns_servers) {
+ DnsServer *server;
+
+ fputs("SERVERS=", f);
+ LIST_FOREACH(servers, server, l->dns_servers) {
+
+ if (server != l->dns_servers)
+ fputc(' ', f);
+
+ v = dns_server_string(server);
+ if (!v) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ fputs(v, f);
+ }
+ fputc('\n', f);
+ }
+
+ if (l->search_domains) {
+ DnsSearchDomain *domain;
+
+ fputs("DOMAINS=", f);
+ LIST_FOREACH(domains, domain, l->search_domains) {
+
+ if (domain != l->search_domains)
+ fputc(' ', f);
+
+ if (domain->route_only)
+ fputc('~', f);
+
+ fputs(DNS_SEARCH_DOMAIN_NAME(domain), f);
+ }
+ fputc('\n', f);
+ }
+
+ if (!set_isempty(l->dnssec_negative_trust_anchors)) {
+ bool space = false;
+ Iterator i;
+ char *nta;
+
+ fputs("NTAS=", f);
+ SET_FOREACH(nta, l->dnssec_negative_trust_anchors, i) {
+
+ if (space)
+ fputc(' ', f);
+
+ fputs(nta, f);
+ space = true;
+ }
+ fputc('\n', f);
+ }
+
+ r = fflush_and_check(f);
+ if (r < 0)
+ goto fail;
+
+ if (rename(temp_path, l->state_file) < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ return 0;
+
+fail:
+ (void) unlink(l->state_file);
+
+ if (temp_path)
+ (void) unlink(temp_path);
+
+ return log_error_errno(r, "Failed to save link data %s: %m", l->state_file);
+}
+
+int link_load_user(Link *l) {
+ _cleanup_free_ char
+ *llmnr = NULL,
+ *mdns = NULL,
+ *dnssec = NULL,
+ *servers = NULL,
+ *domains = NULL,
+ *ntas = NULL;
+
+ ResolveSupport s;
+ int r;
+
+ assert(l);
+ assert(l->state_file);
+
+ /* Try to load only a single time */
+ if (l->loaded)
+ return 0;
+ l->loaded = true;
+
+ if (l->is_managed)
+ return 0; /* if the device is managed, then networkd is our configuration source, not the bus API */
+
+ r = parse_env_file(l->state_file, NEWLINE,
+ "LLMNR", &llmnr,
+ "MDNS", &mdns,
+ "DNSSEC", &dnssec,
+ "SERVERS", &servers,
+ "DOMAINS", &domains,
+ "NTAS", &ntas,
+ NULL);
+ if (r == -ENOENT)
+ return 0;
+ if (r < 0)
+ goto fail;
+
+ link_flush_settings(l);
+
+ /* If we can't recognize the LLMNR or MDNS setting we don't override the default */
+ s = resolve_support_from_string(llmnr);
+ if (s >= 0)
+ l->llmnr_support = s;
+
+ s = resolve_support_from_string(mdns);
+ if (s >= 0)
+ l->mdns_support = s;
+
+ /* If we can't recognize the DNSSEC setting, then set it to invalid, so that the daemon default is used. */
+ l->dnssec_mode = dnssec_mode_from_string(dnssec);
+
+ if (servers) {
+ const char *p = servers;
+
+ for (;;) {
+ _cleanup_free_ char *word = NULL;
+
+ r = extract_first_word(&p, &word, NULL, 0);
+ if (r < 0)
+ goto fail;
+ if (r == 0)
+ break;
+
+ r = link_update_dns_server_one(l, word);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to load DNS server '%s', ignoring: %m", word);
+ continue;
+ }
+ }
+ }
+
+ if (domains) {
+ const char *p = domains;
+
+ for (;;) {
+ _cleanup_free_ char *word = NULL;
+ const char *n;
+ bool is_route;
+
+ r = extract_first_word(&p, &word, NULL, 0);
+ if (r < 0)
+ goto fail;
+ if (r == 0)
+ break;
+
+ is_route = word[0] == '~';
+ n = is_route ? word + 1 : word;
+
+ r = link_update_search_domain_one(l, n, is_route);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to load search domain '%s', ignoring: %m", word);
+ continue;
+ }
+ }
+ }
+
+ if (ntas) {
+ _cleanup_set_free_free_ Set *ns = NULL;
+
+ ns = set_new(&dns_name_hash_ops);
+ if (!ns) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ r = set_put_strsplit(ns, ntas, NULL, 0);
+ if (r < 0)
+ goto fail;
+
+ l->dnssec_negative_trust_anchors = ns;
+ ns = NULL;
+ }
+
+ return 0;
+
+fail:
+ return log_error_errno(r, "Failed to load link data %s: %m", l->state_file);
+}
+
+void link_remove_user(Link *l) {
+ assert(l);
+ assert(l->state_file);
+
+ (void) unlink(l->state_file);
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-link.h b/src/grp-resolve/systemd-resolved/resolved-link.h
new file mode 100644
index 0000000000..8860b878bb
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-link.h
@@ -0,0 +1,118 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <net/if.h>
+
+#include "basic-dns/resolved-dns-rr.h"
+#include "systemd-basic/in-addr-util.h"
+#include "systemd-basic/ratelimit.h"
+#include "systemd-shared/resolve-util.h"
+
+typedef struct Link Link;
+typedef struct LinkAddress LinkAddress;
+
+#include "resolved-dns-search-domain.h"
+#include "resolved-dns-server.h"
+#include "resolved-manager.h"
+
+#define LINK_SEARCH_DOMAINS_MAX 32
+#define LINK_DNS_SERVERS_MAX 32
+
+struct LinkAddress {
+ Link *link;
+
+ int family;
+ union in_addr_union in_addr;
+
+ unsigned char flags, scope;
+
+ DnsResourceRecord *llmnr_address_rr;
+ DnsResourceRecord *llmnr_ptr_rr;
+
+ LIST_FIELDS(LinkAddress, addresses);
+};
+
+struct Link {
+ Manager *manager;
+
+ int ifindex;
+ unsigned flags;
+
+ LIST_HEAD(LinkAddress, addresses);
+
+ LIST_HEAD(DnsServer, dns_servers);
+ DnsServer *current_dns_server;
+ unsigned n_dns_servers;
+
+ LIST_HEAD(DnsSearchDomain, search_domains);
+ unsigned n_search_domains;
+
+ ResolveSupport llmnr_support;
+ ResolveSupport mdns_support;
+ DnssecMode dnssec_mode;
+ Set *dnssec_negative_trust_anchors;
+
+ DnsScope *unicast_scope;
+ DnsScope *llmnr_ipv4_scope;
+ DnsScope *llmnr_ipv6_scope;
+ DnsScope *mdns_ipv4_scope;
+ DnsScope *mdns_ipv6_scope;
+
+ bool is_managed;
+
+ char name[IF_NAMESIZE];
+ uint32_t mtu;
+ uint8_t operstate;
+
+ bool loaded;
+ char *state_file;
+};
+
+int link_new(Manager *m, Link **ret, int ifindex);
+Link *link_free(Link *l);
+int link_process_rtnl(Link *l, sd_netlink_message *m);
+int link_update(Link *l);
+bool link_relevant(Link *l, int family, bool local_multicast);
+LinkAddress* link_find_address(Link *l, int family, const union in_addr_union *in_addr);
+void link_add_rrs(Link *l, bool force_remove);
+
+void link_flush_settings(Link *l);
+void link_set_dnssec_mode(Link *l, DnssecMode mode);
+void link_allocate_scopes(Link *l);
+
+DnsServer* link_set_dns_server(Link *l, DnsServer *s);
+DnsServer* link_get_dns_server(Link *l);
+void link_next_dns_server(Link *l);
+
+DnssecMode link_get_dnssec_mode(Link *l);
+bool link_dnssec_supported(Link *l);
+
+int link_save_user(Link *l);
+int link_load_user(Link *l);
+void link_remove_user(Link *l);
+
+int link_address_new(Link *l, LinkAddress **ret, int family, const union in_addr_union *in_addr);
+LinkAddress *link_address_free(LinkAddress *a);
+int link_address_update_rtnl(LinkAddress *a, sd_netlink_message *m);
+bool link_address_relevant(LinkAddress *l, bool local_multicast);
+void link_address_add_rrs(LinkAddress *a, bool force_remove);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(Link*, link_free);
diff --git a/src/grp-resolve/systemd-resolved/resolved-llmnr.c b/src/grp-resolve/systemd-resolved/resolved-llmnr.c
new file mode 100644
index 0000000000..2a22f20790
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-llmnr.c
@@ -0,0 +1,472 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Tom Gundersen <teg@jklm.no>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+ ***/
+
+#include <netinet/in.h>
+#include <resolv.h>
+
+#include "systemd-basic/fd-util.h"
+
+#include "resolved-llmnr.h"
+#include "resolved-manager.h"
+
+void manager_llmnr_stop(Manager *m) {
+ assert(m);
+
+ m->llmnr_ipv4_udp_event_source = sd_event_source_unref(m->llmnr_ipv4_udp_event_source);
+ m->llmnr_ipv4_udp_fd = safe_close(m->llmnr_ipv4_udp_fd);
+
+ m->llmnr_ipv6_udp_event_source = sd_event_source_unref(m->llmnr_ipv6_udp_event_source);
+ m->llmnr_ipv6_udp_fd = safe_close(m->llmnr_ipv6_udp_fd);
+
+ m->llmnr_ipv4_tcp_event_source = sd_event_source_unref(m->llmnr_ipv4_tcp_event_source);
+ m->llmnr_ipv4_tcp_fd = safe_close(m->llmnr_ipv4_tcp_fd);
+
+ m->llmnr_ipv6_tcp_event_source = sd_event_source_unref(m->llmnr_ipv6_tcp_event_source);
+ m->llmnr_ipv6_tcp_fd = safe_close(m->llmnr_ipv6_tcp_fd);
+}
+
+int manager_llmnr_start(Manager *m) {
+ int r;
+
+ assert(m);
+
+ if (m->llmnr_support == RESOLVE_SUPPORT_NO)
+ return 0;
+
+ r = manager_llmnr_ipv4_udp_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+
+ r = manager_llmnr_ipv4_tcp_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+
+ if (socket_ipv6_is_supported()) {
+ r = manager_llmnr_ipv6_udp_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+
+ r = manager_llmnr_ipv6_tcp_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+
+eaddrinuse:
+ log_warning("There appears to be another LLMNR responder running. Turning off LLMNR support.");
+ m->llmnr_support = RESOLVE_SUPPORT_NO;
+ manager_llmnr_stop(m);
+
+ return 0;
+}
+
+static int on_llmnr_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ DnsTransaction *t = NULL;
+ Manager *m = userdata;
+ DnsScope *scope;
+ int r;
+
+ assert(s);
+ assert(fd >= 0);
+ assert(m);
+
+ r = manager_recv(m, fd, DNS_PROTOCOL_LLMNR, &p);
+ if (r <= 0)
+ return r;
+
+ scope = manager_find_scope(m, p);
+ if (!scope)
+ log_warning("Got LLMNR UDP packet on unknown scope. Ignoring.");
+ else if (dns_packet_validate_reply(p) > 0) {
+ log_debug("Got LLMNR UDP reply packet for id %u", DNS_PACKET_ID(p));
+
+ dns_scope_check_conflicts(scope, p);
+
+ t = hashmap_get(m->dns_transactions, UINT_TO_PTR(DNS_PACKET_ID(p)));
+ if (t)
+ dns_transaction_process_reply(t, p);
+
+ } else if (dns_packet_validate_query(p) > 0) {
+ log_debug("Got LLMNR UDP query packet for id %u", DNS_PACKET_ID(p));
+
+ dns_scope_process_query(scope, NULL, p);
+ } else
+ log_debug("Invalid LLMNR UDP packet, ignoring.");
+
+ return 0;
+}
+
+int manager_llmnr_ipv4_udp_fd(Manager *m) {
+ union sockaddr_union sa = {
+ .in.sin_family = AF_INET,
+ .in.sin_port = htobe16(LLMNR_PORT),
+ };
+ static const int one = 1, pmtu = IP_PMTUDISC_DONT, ttl = 255;
+ int r;
+
+ assert(m);
+
+ if (m->llmnr_ipv4_udp_fd >= 0)
+ return m->llmnr_ipv4_udp_fd;
+
+ m->llmnr_ipv4_udp_fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (m->llmnr_ipv4_udp_fd < 0)
+ return -errno;
+
+ /* RFC 4795, section 2.5 recommends setting the TTL of UDP packets to 255. */
+ r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv4_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ /* Disable Don't-Fragment bit in the IP header */
+ r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MTU_DISCOVER, &pmtu, sizeof(pmtu));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = bind(m->llmnr_ipv4_udp_fd, &sa.sa, sizeof(sa.in));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = sd_event_add_io(m->event, &m->llmnr_ipv4_udp_event_source, m->llmnr_ipv4_udp_fd, EPOLLIN, on_llmnr_packet, m);
+ if (r < 0)
+ goto fail;
+
+ (void) sd_event_source_set_description(m->llmnr_ipv4_udp_event_source, "llmnr-ipv4-udp");
+
+ return m->llmnr_ipv4_udp_fd;
+
+fail:
+ m->llmnr_ipv4_udp_fd = safe_close(m->llmnr_ipv4_udp_fd);
+ return r;
+}
+
+int manager_llmnr_ipv6_udp_fd(Manager *m) {
+ union sockaddr_union sa = {
+ .in6.sin6_family = AF_INET6,
+ .in6.sin6_port = htobe16(LLMNR_PORT),
+ };
+ static const int one = 1, ttl = 255;
+ int r;
+
+ assert(m);
+
+ if (m->llmnr_ipv6_udp_fd >= 0)
+ return m->llmnr_ipv6_udp_fd;
+
+ m->llmnr_ipv6_udp_fd = socket(AF_INET6, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (m->llmnr_ipv6_udp_fd < 0)
+ return -errno;
+
+ r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ /* RFC 4795, section 2.5 recommends setting the TTL of UDP packets to 255. */
+ r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv6_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = bind(m->llmnr_ipv6_udp_fd, &sa.sa, sizeof(sa.in6));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = sd_event_add_io(m->event, &m->llmnr_ipv6_udp_event_source, m->llmnr_ipv6_udp_fd, EPOLLIN, on_llmnr_packet, m);
+ if (r < 0)
+ goto fail;
+
+ (void) sd_event_source_set_description(m->llmnr_ipv6_udp_event_source, "llmnr-ipv6-udp");
+
+ return m->llmnr_ipv6_udp_fd;
+
+fail:
+ m->llmnr_ipv6_udp_fd = safe_close(m->llmnr_ipv6_udp_fd);
+ return r;
+}
+
+static int on_llmnr_stream_packet(DnsStream *s) {
+ DnsScope *scope;
+
+ assert(s);
+ assert(s->read_packet);
+
+ scope = manager_find_scope(s->manager, s->read_packet);
+ if (!scope)
+ log_warning("Got LLMNR TCP packet on unknown scope. Ignoring.");
+ else if (dns_packet_validate_query(s->read_packet) > 0) {
+ log_debug("Got LLMNR TCP query packet for id %u", DNS_PACKET_ID(s->read_packet));
+
+ dns_scope_process_query(scope, s, s->read_packet);
+ } else
+ log_debug("Invalid LLMNR TCP packet, ignoring.");
+
+ dns_stream_unref(s);
+ return 0;
+}
+
+static int on_llmnr_stream(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ DnsStream *stream;
+ Manager *m = userdata;
+ int cfd, r;
+
+ cfd = accept4(fd, NULL, NULL, SOCK_NONBLOCK|SOCK_CLOEXEC);
+ if (cfd < 0) {
+ if (errno == EAGAIN || errno == EINTR)
+ return 0;
+
+ return -errno;
+ }
+
+ r = dns_stream_new(m, &stream, DNS_PROTOCOL_LLMNR, cfd);
+ if (r < 0) {
+ safe_close(cfd);
+ return r;
+ }
+
+ stream->on_packet = on_llmnr_stream_packet;
+ return 0;
+}
+
+int manager_llmnr_ipv4_tcp_fd(Manager *m) {
+ union sockaddr_union sa = {
+ .in.sin_family = AF_INET,
+ .in.sin_port = htobe16(LLMNR_PORT),
+ };
+ static const int one = 1, pmtu = IP_PMTUDISC_DONT;
+ int r;
+
+ assert(m);
+
+ if (m->llmnr_ipv4_tcp_fd >= 0)
+ return m->llmnr_ipv4_tcp_fd;
+
+ m->llmnr_ipv4_tcp_fd = socket(AF_INET, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (m->llmnr_ipv4_tcp_fd < 0)
+ return -errno;
+
+ /* RFC 4795, section 2.5. requires setting the TTL of TCP streams to 1 */
+ r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_TTL, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv4_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ /* Disable Don't-Fragment bit in the IP header */
+ r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_MTU_DISCOVER, &pmtu, sizeof(pmtu));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = bind(m->llmnr_ipv4_tcp_fd, &sa.sa, sizeof(sa.in));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = listen(m->llmnr_ipv4_tcp_fd, SOMAXCONN);
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = sd_event_add_io(m->event, &m->llmnr_ipv4_tcp_event_source, m->llmnr_ipv4_tcp_fd, EPOLLIN, on_llmnr_stream, m);
+ if (r < 0)
+ goto fail;
+
+ (void) sd_event_source_set_description(m->llmnr_ipv4_tcp_event_source, "llmnr-ipv4-tcp");
+
+ return m->llmnr_ipv4_tcp_fd;
+
+fail:
+ m->llmnr_ipv4_tcp_fd = safe_close(m->llmnr_ipv4_tcp_fd);
+ return r;
+}
+
+int manager_llmnr_ipv6_tcp_fd(Manager *m) {
+ union sockaddr_union sa = {
+ .in6.sin6_family = AF_INET6,
+ .in6.sin6_port = htobe16(LLMNR_PORT),
+ };
+ static const int one = 1;
+ int r;
+
+ assert(m);
+
+ if (m->llmnr_ipv6_tcp_fd >= 0)
+ return m->llmnr_ipv6_tcp_fd;
+
+ m->llmnr_ipv6_tcp_fd = socket(AF_INET6, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (m->llmnr_ipv6_tcp_fd < 0)
+ return -errno;
+
+ /* RFC 4795, section 2.5. requires setting the TTL of TCP streams to 1 */
+ r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv6_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = bind(m->llmnr_ipv6_tcp_fd, &sa.sa, sizeof(sa.in6));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = listen(m->llmnr_ipv6_tcp_fd, SOMAXCONN);
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = sd_event_add_io(m->event, &m->llmnr_ipv6_tcp_event_source, m->llmnr_ipv6_tcp_fd, EPOLLIN, on_llmnr_stream, m);
+ if (r < 0)
+ goto fail;
+
+ (void) sd_event_source_set_description(m->llmnr_ipv6_tcp_event_source, "llmnr-ipv6-tcp");
+
+ return m->llmnr_ipv6_tcp_fd;
+
+fail:
+ m->llmnr_ipv6_tcp_fd = safe_close(m->llmnr_ipv6_tcp_fd);
+ return r;
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-llmnr.h b/src/grp-resolve/systemd-resolved/resolved-llmnr.h
new file mode 100644
index 0000000000..8133582fa7
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-llmnr.h
@@ -0,0 +1,32 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "resolved-manager.h"
+
+#define LLMNR_PORT 5355
+
+int manager_llmnr_ipv4_udp_fd(Manager *m);
+int manager_llmnr_ipv6_udp_fd(Manager *m);
+int manager_llmnr_ipv4_tcp_fd(Manager *m);
+int manager_llmnr_ipv6_tcp_fd(Manager *m);
+
+void manager_llmnr_stop(Manager *m);
+int manager_llmnr_start(Manager *m);
diff --git a/src/grp-resolve/systemd-resolved/resolved-manager.c b/src/grp-resolve/systemd-resolved/resolved-manager.c
new file mode 100644
index 0000000000..e7ed54db1c
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-manager.c
@@ -0,0 +1,1379 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Tom Gundersen <teg@jklm.no>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+ ***/
+
+#include <netinet/in.h>
+#include <poll.h>
+#include <sys/ioctl.h>
+
+#include "sd-netlink/netlink-util.h"
+#include "systemd-basic/af-list.h"
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/dirent-util.h"
+#include "systemd-basic/fd-util.h"
+#include "systemd-basic/fileio-label.h"
+#include "systemd-basic/hostname-util.h"
+#include "systemd-basic/io-util.h"
+#include "systemd-basic/ordered-set.h"
+#include "systemd-basic/parse-util.h"
+#include "systemd-basic/random-util.h"
+#include "systemd-basic/socket-util.h"
+#include "systemd-basic/string-table.h"
+#include "systemd-basic/string-util.h"
+#include "systemd-basic/utf8.h"
+#include "systemd-network/network-internal.h"
+#include "systemd-shared/dns-domain.h"
+
+#include "resolved-bus.h"
+#include "resolved-conf.h"
+#include "resolved-dns-stub.h"
+#include "resolved-etc-hosts.h"
+#include "resolved-llmnr.h"
+#include "resolved-manager.h"
+#include "resolved-mdns.h"
+#include "resolved-resolv-conf.h"
+
+#define SEND_TIMEOUT_USEC (200 * USEC_PER_MSEC)
+
+static int manager_process_link(sd_netlink *rtnl, sd_netlink_message *mm, void *userdata) {
+ Manager *m = userdata;
+ uint16_t type;
+ Link *l;
+ int ifindex, r;
+
+ assert(rtnl);
+ assert(m);
+ assert(mm);
+
+ r = sd_netlink_message_get_type(mm, &type);
+ if (r < 0)
+ goto fail;
+
+ r = sd_rtnl_message_link_get_ifindex(mm, &ifindex);
+ if (r < 0)
+ goto fail;
+
+ l = hashmap_get(m->links, INT_TO_PTR(ifindex));
+
+ switch (type) {
+
+ case RTM_NEWLINK:{
+ bool is_new = !l;
+
+ if (!l) {
+ r = link_new(m, &l, ifindex);
+ if (r < 0)
+ goto fail;
+ }
+
+ r = link_process_rtnl(l, mm);
+ if (r < 0)
+ goto fail;
+
+ r = link_update(l);
+ if (r < 0)
+ goto fail;
+
+ if (is_new)
+ log_debug("Found new link %i/%s", ifindex, l->name);
+
+ break;
+ }
+
+ case RTM_DELLINK:
+ if (l) {
+ log_debug("Removing link %i/%s", l->ifindex, l->name);
+ link_remove_user(l);
+ link_free(l);
+ }
+
+ break;
+ }
+
+ return 0;
+
+fail:
+ log_warning_errno(r, "Failed to process RTNL link message: %m");
+ return 0;
+}
+
+static int manager_process_address(sd_netlink *rtnl, sd_netlink_message *mm, void *userdata) {
+ Manager *m = userdata;
+ union in_addr_union address;
+ uint16_t type;
+ int r, ifindex, family;
+ LinkAddress *a;
+ Link *l;
+
+ assert(rtnl);
+ assert(mm);
+ assert(m);
+
+ r = sd_netlink_message_get_type(mm, &type);
+ if (r < 0)
+ goto fail;
+
+ r = sd_rtnl_message_addr_get_ifindex(mm, &ifindex);
+ if (r < 0)
+ goto fail;
+
+ l = hashmap_get(m->links, INT_TO_PTR(ifindex));
+ if (!l)
+ return 0;
+
+ r = sd_rtnl_message_addr_get_family(mm, &family);
+ if (r < 0)
+ goto fail;
+
+ switch (family) {
+
+ case AF_INET:
+ r = sd_netlink_message_read_in_addr(mm, IFA_LOCAL, &address.in);
+ if (r < 0) {
+ r = sd_netlink_message_read_in_addr(mm, IFA_ADDRESS, &address.in);
+ if (r < 0)
+ goto fail;
+ }
+
+ break;
+
+ case AF_INET6:
+ r = sd_netlink_message_read_in6_addr(mm, IFA_LOCAL, &address.in6);
+ if (r < 0) {
+ r = sd_netlink_message_read_in6_addr(mm, IFA_ADDRESS, &address.in6);
+ if (r < 0)
+ goto fail;
+ }
+
+ break;
+
+ default:
+ return 0;
+ }
+
+ a = link_find_address(l, family, &address);
+
+ switch (type) {
+
+ case RTM_NEWADDR:
+
+ if (!a) {
+ r = link_address_new(l, &a, family, &address);
+ if (r < 0)
+ return r;
+ }
+
+ r = link_address_update_rtnl(a, mm);
+ if (r < 0)
+ return r;
+
+ break;
+
+ case RTM_DELADDR:
+ link_address_free(a);
+ break;
+ }
+
+ return 0;
+
+fail:
+ log_warning_errno(r, "Failed to process RTNL address message: %m");
+ return 0;
+}
+
+static int manager_rtnl_listen(Manager *m) {
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
+ sd_netlink_message *i;
+ int r;
+
+ assert(m);
+
+ /* First, subscribe to interfaces coming and going */
+ r = sd_netlink_open(&m->rtnl);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_attach_event(m->rtnl, m->event, SD_EVENT_PRIORITY_IMPORTANT);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_add_match(m->rtnl, RTM_NEWLINK, manager_process_link, m);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_add_match(m->rtnl, RTM_DELLINK, manager_process_link, m);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_add_match(m->rtnl, RTM_NEWADDR, manager_process_address, m);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_add_match(m->rtnl, RTM_DELADDR, manager_process_address, m);
+ if (r < 0)
+ return r;
+
+ /* Then, enumerate all links */
+ r = sd_rtnl_message_new_link(m->rtnl, &req, RTM_GETLINK, 0);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_request_dump(req, true);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_call(m->rtnl, req, 0, &reply);
+ if (r < 0)
+ return r;
+
+ for (i = reply; i; i = sd_netlink_message_next(i)) {
+ r = manager_process_link(m->rtnl, i, m);
+ if (r < 0)
+ return r;
+ }
+
+ req = sd_netlink_message_unref(req);
+ reply = sd_netlink_message_unref(reply);
+
+ /* Finally, enumerate all addresses, too */
+ r = sd_rtnl_message_new_addr(m->rtnl, &req, RTM_GETADDR, 0, AF_UNSPEC);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_request_dump(req, true);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_call(m->rtnl, req, 0, &reply);
+ if (r < 0)
+ return r;
+
+ for (i = reply; i; i = sd_netlink_message_next(i)) {
+ r = manager_process_address(m->rtnl, i, m);
+ if (r < 0)
+ return r;
+ }
+
+ return r;
+}
+
+static int on_network_event(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ Manager *m = userdata;
+ Iterator i;
+ Link *l;
+ int r;
+
+ assert(m);
+
+ sd_network_monitor_flush(m->network_monitor);
+
+ HASHMAP_FOREACH(l, m->links, i) {
+ r = link_update(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to update monitor information for %i: %m", l->ifindex);
+ }
+
+ (void) manager_write_resolv_conf(m);
+
+ return 0;
+}
+
+static int manager_network_monitor_listen(Manager *m) {
+ int r, fd, events;
+
+ assert(m);
+
+ r = sd_network_monitor_new(&m->network_monitor, NULL);
+ if (r < 0)
+ return r;
+
+ fd = sd_network_monitor_get_fd(m->network_monitor);
+ if (fd < 0)
+ return fd;
+
+ events = sd_network_monitor_get_events(m->network_monitor);
+ if (events < 0)
+ return events;
+
+ r = sd_event_add_io(m->event, &m->network_event_source, fd, events, &on_network_event, m);
+ if (r < 0)
+ return r;
+
+ r = sd_event_source_set_priority(m->network_event_source, SD_EVENT_PRIORITY_IMPORTANT+5);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_source_set_description(m->network_event_source, "network-monitor");
+
+ return 0;
+}
+
+static int determine_hostname(char **llmnr_hostname, char **mdns_hostname) {
+ _cleanup_free_ char *h = NULL, *n = NULL;
+ char label[DNS_LABEL_MAX];
+ const char *p;
+ int r, k;
+
+ assert(llmnr_hostname);
+ assert(mdns_hostname);
+
+ /* Extract and normalize the first label of the locally
+ * configured hostname, and check it's not "localhost". */
+
+ h = gethostname_malloc();
+ if (!h)
+ return log_oom();
+
+ p = h;
+ r = dns_label_unescape(&p, label, sizeof(label));
+ if (r < 0)
+ return log_error_errno(r, "Failed to unescape host name: %m");
+ if (r == 0) {
+ log_error("Couldn't find a single label in hosntame.");
+ return -EINVAL;
+ }
+
+ k = dns_label_undo_idna(label, r, label, sizeof(label));
+ if (k < 0)
+ return log_error_errno(k, "Failed to undo IDNA: %m");
+ if (k > 0)
+ r = k;
+
+ if (!utf8_is_valid(label)) {
+ log_error("System hostname is not UTF-8 clean.");
+ return -EINVAL;
+ }
+
+ r = dns_label_escape_new(label, r, &n);
+ if (r < 0)
+ return log_error_errno(r, "Failed to escape host name: %m");
+
+ if (is_localhost(n)) {
+ log_debug("System hostname is 'localhost', ignoring.");
+ return -EINVAL;
+ }
+
+ r = dns_name_concat(n, "local", mdns_hostname);
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine mDNS hostname: %m");
+
+ *llmnr_hostname = n;
+ n = NULL;
+
+ return 0;
+}
+
+static int on_hostname_change(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
+ _cleanup_free_ char *llmnr_hostname = NULL, *mdns_hostname = NULL;
+ Manager *m = userdata;
+ int r;
+
+ assert(m);
+
+ r = determine_hostname(&llmnr_hostname, &mdns_hostname);
+ if (r < 0)
+ return 0; /* ignore invalid hostnames */
+
+ if (streq(llmnr_hostname, m->llmnr_hostname) && streq(mdns_hostname, m->mdns_hostname))
+ return 0;
+
+ log_info("System hostname changed to '%s'.", llmnr_hostname);
+
+ free(m->llmnr_hostname);
+ free(m->mdns_hostname);
+
+ m->llmnr_hostname = llmnr_hostname;
+ m->mdns_hostname = mdns_hostname;
+
+ llmnr_hostname = mdns_hostname = NULL;
+
+ manager_refresh_rrs(m);
+
+ return 0;
+}
+
+static int manager_watch_hostname(Manager *m) {
+ int r;
+
+ assert(m);
+
+ m->hostname_fd = open("/proc/sys/kernel/hostname", O_RDONLY|O_CLOEXEC|O_NDELAY|O_NOCTTY);
+ if (m->hostname_fd < 0) {
+ log_warning_errno(errno, "Failed to watch hostname: %m");
+ return 0;
+ }
+
+ r = sd_event_add_io(m->event, &m->hostname_event_source, m->hostname_fd, 0, on_hostname_change, m);
+ if (r < 0) {
+ if (r == -EPERM)
+ /* kernels prior to 3.2 don't support polling this file. Ignore the failure. */
+ m->hostname_fd = safe_close(m->hostname_fd);
+ else
+ return log_error_errno(r, "Failed to add hostname event source: %m");
+ }
+
+ (void) sd_event_source_set_description(m->hostname_event_source, "hostname");
+
+ r = determine_hostname(&m->llmnr_hostname, &m->mdns_hostname);
+ if (r < 0) {
+ log_info("Defaulting to hostname 'gnu-linux'.");
+ m->llmnr_hostname = strdup("gnu-linux");
+ if (!m->llmnr_hostname)
+ return log_oom();
+
+ m->mdns_hostname = strdup("gnu-linux.local");
+ if (!m->mdns_hostname)
+ return log_oom();
+ } else
+ log_info("Using system hostname '%s'.", m->llmnr_hostname);
+
+ return 0;
+}
+
+static int manager_sigusr1(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
+ _cleanup_free_ char *buffer = NULL;
+ _cleanup_fclose_ FILE *f = NULL;
+ Manager *m = userdata;
+ size_t size = 0;
+ DnsScope *scope;
+
+ assert(s);
+ assert(si);
+ assert(m);
+
+ f = open_memstream(&buffer, &size);
+ if (!f)
+ return log_oom();
+
+ LIST_FOREACH(scopes, scope, m->dns_scopes)
+ dns_scope_dump(scope, f);
+
+ if (fflush_and_check(f) < 0)
+ return log_oom();
+
+ log_dump(LOG_INFO, buffer);
+ return 0;
+}
+
+static int manager_sigusr2(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
+ Manager *m = userdata;
+
+ assert(s);
+ assert(si);
+ assert(m);
+
+ manager_flush_caches(m);
+
+ return 0;
+}
+
+int manager_new(Manager **ret) {
+ _cleanup_(manager_freep) Manager *m = NULL;
+ int r;
+
+ assert(ret);
+
+ m = new0(Manager, 1);
+ if (!m)
+ return -ENOMEM;
+
+ m->llmnr_ipv4_udp_fd = m->llmnr_ipv6_udp_fd = -1;
+ m->llmnr_ipv4_tcp_fd = m->llmnr_ipv6_tcp_fd = -1;
+ m->mdns_ipv4_fd = m->mdns_ipv6_fd = -1;
+ m->dns_stub_udp_fd = m->dns_stub_tcp_fd = -1;
+ m->hostname_fd = -1;
+
+ m->llmnr_support = RESOLVE_SUPPORT_YES;
+ m->mdns_support = RESOLVE_SUPPORT_NO;
+ m->dnssec_mode = DEFAULT_DNSSEC_MODE;
+ m->enable_cache = true;
+ m->read_resolv_conf = true;
+ m->need_builtin_fallbacks = true;
+ m->etc_hosts_last = m->etc_hosts_mtime = USEC_INFINITY;
+
+ r = dns_trust_anchor_load(&m->trust_anchor);
+ if (r < 0)
+ return r;
+
+ r = manager_parse_config_file(m);
+ if (r < 0)
+ return r;
+
+ r = sd_event_default(&m->event);
+ if (r < 0)
+ return r;
+
+ sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL);
+ sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL);
+
+ sd_event_set_watchdog(m->event, true);
+
+ r = manager_watch_hostname(m);
+ if (r < 0)
+ return r;
+
+ r = dns_scope_new(m, &m->unicast_scope, NULL, DNS_PROTOCOL_DNS, AF_UNSPEC);
+ if (r < 0)
+ return r;
+
+ r = manager_network_monitor_listen(m);
+ if (r < 0)
+ return r;
+
+ r = manager_rtnl_listen(m);
+ if (r < 0)
+ return r;
+
+ r = manager_connect_bus(m);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_add_signal(m->event, &m->sigusr1_event_source, SIGUSR1, manager_sigusr1, m);
+ (void) sd_event_add_signal(m->event, &m->sigusr2_event_source, SIGUSR2, manager_sigusr2, m);
+
+ manager_cleanup_saved_user(m);
+
+ *ret = m;
+ m = NULL;
+
+ return 0;
+}
+
+int manager_start(Manager *m) {
+ int r;
+
+ assert(m);
+
+ r = manager_dns_stub_start(m);
+ if (r < 0)
+ return r;
+
+ r = manager_llmnr_start(m);
+ if (r < 0)
+ return r;
+
+ r = manager_mdns_start(m);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+Manager *manager_free(Manager *m) {
+ Link *l;
+
+ if (!m)
+ return NULL;
+
+ dns_server_unlink_all(m->dns_servers);
+ dns_server_unlink_all(m->fallback_dns_servers);
+ dns_search_domain_unlink_all(m->search_domains);
+
+ while ((l = hashmap_first(m->links)))
+ link_free(l);
+
+ while (m->dns_queries)
+ dns_query_free(m->dns_queries);
+
+ dns_scope_free(m->unicast_scope);
+
+ /* At this point only orphaned streams should remain. All others should have been freed already by their
+ * owners */
+ while (m->dns_streams)
+ dns_stream_unref(m->dns_streams);
+
+ hashmap_free(m->links);
+ hashmap_free(m->dns_transactions);
+
+ sd_event_source_unref(m->network_event_source);
+ sd_network_monitor_unref(m->network_monitor);
+
+ sd_netlink_unref(m->rtnl);
+ sd_event_source_unref(m->rtnl_event_source);
+
+ manager_llmnr_stop(m);
+ manager_mdns_stop(m);
+ manager_dns_stub_stop(m);
+
+ sd_bus_slot_unref(m->prepare_for_sleep_slot);
+ sd_event_source_unref(m->bus_retry_event_source);
+ sd_bus_unref(m->bus);
+
+ sd_event_source_unref(m->sigusr1_event_source);
+ sd_event_source_unref(m->sigusr2_event_source);
+
+ sd_event_unref(m->event);
+
+ dns_resource_key_unref(m->llmnr_host_ipv4_key);
+ dns_resource_key_unref(m->llmnr_host_ipv6_key);
+
+ sd_event_source_unref(m->hostname_event_source);
+ safe_close(m->hostname_fd);
+ free(m->llmnr_hostname);
+ free(m->mdns_hostname);
+
+ dns_trust_anchor_flush(&m->trust_anchor);
+ manager_etc_hosts_flush(m);
+
+ free(m);
+
+ return NULL;
+}
+
+int manager_recv(Manager *m, int fd, DnsProtocol protocol, DnsPacket **ret) {
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ union {
+ struct cmsghdr header; /* For alignment */
+ uint8_t buffer[CMSG_SPACE(MAXSIZE(struct in_pktinfo, struct in6_pktinfo))
+ + CMSG_SPACE(int) /* ttl/hoplimit */
+ + EXTRA_CMSG_SPACE /* kernel appears to require extra buffer space */];
+ } control;
+ union sockaddr_union sa;
+ struct msghdr mh = {};
+ struct cmsghdr *cmsg;
+ struct iovec iov;
+ ssize_t ms, l;
+ int r;
+
+ assert(m);
+ assert(fd >= 0);
+ assert(ret);
+
+ ms = next_datagram_size_fd(fd);
+ if (ms < 0)
+ return ms;
+
+ r = dns_packet_new(&p, protocol, ms);
+ if (r < 0)
+ return r;
+
+ iov.iov_base = DNS_PACKET_DATA(p);
+ iov.iov_len = p->allocated;
+
+ mh.msg_name = &sa.sa;
+ mh.msg_namelen = sizeof(sa);
+ mh.msg_iov = &iov;
+ mh.msg_iovlen = 1;
+ mh.msg_control = &control;
+ mh.msg_controllen = sizeof(control);
+
+ l = recvmsg(fd, &mh, 0);
+ if (l == 0)
+ return 0;
+ if (l < 0) {
+ if (errno == EAGAIN || errno == EINTR)
+ return 0;
+
+ return -errno;
+ }
+
+ assert(!(mh.msg_flags & MSG_CTRUNC));
+ assert(!(mh.msg_flags & MSG_TRUNC));
+
+ p->size = (size_t) l;
+
+ p->family = sa.sa.sa_family;
+ p->ipproto = IPPROTO_UDP;
+ if (p->family == AF_INET) {
+ p->sender.in = sa.in.sin_addr;
+ p->sender_port = be16toh(sa.in.sin_port);
+ } else if (p->family == AF_INET6) {
+ p->sender.in6 = sa.in6.sin6_addr;
+ p->sender_port = be16toh(sa.in6.sin6_port);
+ p->ifindex = sa.in6.sin6_scope_id;
+ } else
+ return -EAFNOSUPPORT;
+
+ CMSG_FOREACH(cmsg, &mh) {
+
+ if (cmsg->cmsg_level == IPPROTO_IPV6) {
+ assert(p->family == AF_INET6);
+
+ switch (cmsg->cmsg_type) {
+
+ case IPV6_PKTINFO: {
+ struct in6_pktinfo *i = (struct in6_pktinfo*) CMSG_DATA(cmsg);
+
+ if (p->ifindex <= 0)
+ p->ifindex = i->ipi6_ifindex;
+
+ p->destination.in6 = i->ipi6_addr;
+ break;
+ }
+
+ case IPV6_HOPLIMIT:
+ p->ttl = *(int *) CMSG_DATA(cmsg);
+ break;
+
+ }
+ } else if (cmsg->cmsg_level == IPPROTO_IP) {
+ assert(p->family == AF_INET);
+
+ switch (cmsg->cmsg_type) {
+
+ case IP_PKTINFO: {
+ struct in_pktinfo *i = (struct in_pktinfo*) CMSG_DATA(cmsg);
+
+ if (p->ifindex <= 0)
+ p->ifindex = i->ipi_ifindex;
+
+ p->destination.in = i->ipi_addr;
+ break;
+ }
+
+ case IP_TTL:
+ p->ttl = *(int *) CMSG_DATA(cmsg);
+ break;
+ }
+ }
+ }
+
+ /* The Linux kernel sets the interface index to the loopback
+ * device if the packet came from the local host since it
+ * avoids the routing table in such a case. Let's unset the
+ * interface index in such a case. */
+ if (p->ifindex == LOOPBACK_IFINDEX)
+ p->ifindex = 0;
+
+ if (protocol != DNS_PROTOCOL_DNS) {
+ /* If we don't know the interface index still, we look for the
+ * first local interface with a matching address. Yuck! */
+ if (p->ifindex <= 0)
+ p->ifindex = manager_find_ifindex(m, p->family, &p->destination);
+ }
+
+ *ret = p;
+ p = NULL;
+
+ return 1;
+}
+
+static int sendmsg_loop(int fd, struct msghdr *mh, int flags) {
+ int r;
+
+ assert(fd >= 0);
+ assert(mh);
+
+ for (;;) {
+ if (sendmsg(fd, mh, flags) >= 0)
+ return 0;
+
+ if (errno == EINTR)
+ continue;
+
+ if (errno != EAGAIN)
+ return -errno;
+
+ r = fd_wait_for_event(fd, POLLOUT, SEND_TIMEOUT_USEC);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -ETIMEDOUT;
+ }
+}
+
+static int write_loop(int fd, void *message, size_t length) {
+ int r;
+
+ assert(fd >= 0);
+ assert(message);
+
+ for (;;) {
+ if (write(fd, message, length) >= 0)
+ return 0;
+
+ if (errno == EINTR)
+ continue;
+
+ if (errno != EAGAIN)
+ return -errno;
+
+ r = fd_wait_for_event(fd, POLLOUT, SEND_TIMEOUT_USEC);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -ETIMEDOUT;
+ }
+}
+
+int manager_write(Manager *m, int fd, DnsPacket *p) {
+ int r;
+
+ log_debug("Sending %s packet with id %" PRIu16 ".", DNS_PACKET_QR(p) ? "response" : "query", DNS_PACKET_ID(p));
+
+ r = write_loop(fd, DNS_PACKET_DATA(p), p->size);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+static int manager_ipv4_send(
+ Manager *m,
+ int fd,
+ int ifindex,
+ const struct in_addr *destination,
+ uint16_t port,
+ const struct in_addr *source,
+ DnsPacket *p) {
+ union sockaddr_union sa = {
+ .in.sin_family = AF_INET,
+ };
+ union {
+ struct cmsghdr header; /* For alignment */
+ uint8_t buffer[CMSG_SPACE(sizeof(struct in_pktinfo))];
+ } control;
+ struct msghdr mh = {};
+ struct iovec iov;
+
+ assert(m);
+ assert(fd >= 0);
+ assert(destination);
+ assert(port > 0);
+ assert(p);
+
+ iov.iov_base = DNS_PACKET_DATA(p);
+ iov.iov_len = p->size;
+
+ sa.in.sin_addr = *destination;
+ sa.in.sin_port = htobe16(port),
+
+ mh.msg_iov = &iov;
+ mh.msg_iovlen = 1;
+ mh.msg_name = &sa.sa;
+ mh.msg_namelen = sizeof(sa.in);
+
+ if (ifindex > 0) {
+ struct cmsghdr *cmsg;
+ struct in_pktinfo *pi;
+
+ zero(control);
+
+ mh.msg_control = &control;
+ mh.msg_controllen = CMSG_LEN(sizeof(struct in_pktinfo));
+
+ cmsg = CMSG_FIRSTHDR(&mh);
+ cmsg->cmsg_len = mh.msg_controllen;
+ cmsg->cmsg_level = IPPROTO_IP;
+ cmsg->cmsg_type = IP_PKTINFO;
+
+ pi = (struct in_pktinfo*) CMSG_DATA(cmsg);
+ pi->ipi_ifindex = ifindex;
+
+ if (source)
+ pi->ipi_spec_dst = *source;
+ }
+
+ return sendmsg_loop(fd, &mh, 0);
+}
+
+static int manager_ipv6_send(
+ Manager *m,
+ int fd,
+ int ifindex,
+ const struct in6_addr *destination,
+ uint16_t port,
+ const struct in6_addr *source,
+ DnsPacket *p) {
+
+ union sockaddr_union sa = {
+ .in6.sin6_family = AF_INET6,
+ };
+ union {
+ struct cmsghdr header; /* For alignment */
+ uint8_t buffer[CMSG_SPACE(sizeof(struct in6_pktinfo))];
+ } control;
+ struct msghdr mh = {};
+ struct iovec iov;
+
+ assert(m);
+ assert(fd >= 0);
+ assert(destination);
+ assert(port > 0);
+ assert(p);
+
+ iov.iov_base = DNS_PACKET_DATA(p);
+ iov.iov_len = p->size;
+
+ sa.in6.sin6_addr = *destination;
+ sa.in6.sin6_port = htobe16(port),
+ sa.in6.sin6_scope_id = ifindex;
+
+ mh.msg_iov = &iov;
+ mh.msg_iovlen = 1;
+ mh.msg_name = &sa.sa;
+ mh.msg_namelen = sizeof(sa.in6);
+
+ if (ifindex > 0) {
+ struct cmsghdr *cmsg;
+ struct in6_pktinfo *pi;
+
+ zero(control);
+
+ mh.msg_control = &control;
+ mh.msg_controllen = CMSG_LEN(sizeof(struct in6_pktinfo));
+
+ cmsg = CMSG_FIRSTHDR(&mh);
+ cmsg->cmsg_len = mh.msg_controllen;
+ cmsg->cmsg_level = IPPROTO_IPV6;
+ cmsg->cmsg_type = IPV6_PKTINFO;
+
+ pi = (struct in6_pktinfo*) CMSG_DATA(cmsg);
+ pi->ipi6_ifindex = ifindex;
+
+ if (source)
+ pi->ipi6_addr = *source;
+ }
+
+ return sendmsg_loop(fd, &mh, 0);
+}
+
+int manager_send(
+ Manager *m,
+ int fd,
+ int ifindex,
+ int family,
+ const union in_addr_union *destination,
+ uint16_t port,
+ const union in_addr_union *source,
+ DnsPacket *p) {
+
+ assert(m);
+ assert(fd >= 0);
+ assert(destination);
+ assert(port > 0);
+ assert(p);
+
+ log_debug("Sending %s packet with id %" PRIu16 " on interface %i/%s.", DNS_PACKET_QR(p) ? "response" : "query", DNS_PACKET_ID(p), ifindex, af_to_name(family));
+
+ if (family == AF_INET)
+ return manager_ipv4_send(m, fd, ifindex, &destination->in, port, &source->in, p);
+ if (family == AF_INET6)
+ return manager_ipv6_send(m, fd, ifindex, &destination->in6, port, &source->in6, p);
+
+ return -EAFNOSUPPORT;
+}
+
+uint32_t manager_find_mtu(Manager *m) {
+ uint32_t mtu = 0;
+ Link *l;
+ Iterator i;
+
+ /* If we don't know on which link a DNS packet would be
+ * delivered, let's find the largest MTU that works on all
+ * interfaces we know of */
+
+ HASHMAP_FOREACH(l, m->links, i) {
+ if (l->mtu <= 0)
+ continue;
+
+ if (mtu <= 0 || l->mtu < mtu)
+ mtu = l->mtu;
+ }
+
+ return mtu;
+}
+
+int manager_find_ifindex(Manager *m, int family, const union in_addr_union *in_addr) {
+ LinkAddress *a;
+
+ assert(m);
+
+ a = manager_find_link_address(m, family, in_addr);
+ if (a)
+ return a->link->ifindex;
+
+ return 0;
+}
+
+void manager_refresh_rrs(Manager *m) {
+ Iterator i;
+ Link *l;
+
+ assert(m);
+
+ m->llmnr_host_ipv4_key = dns_resource_key_unref(m->llmnr_host_ipv4_key);
+ m->llmnr_host_ipv6_key = dns_resource_key_unref(m->llmnr_host_ipv6_key);
+
+ HASHMAP_FOREACH(l, m->links, i) {
+ link_add_rrs(l, true);
+ link_add_rrs(l, false);
+ }
+}
+
+int manager_next_hostname(Manager *m) {
+ const char *p;
+ uint64_t u, a;
+ char *h, *k;
+ int r;
+
+ assert(m);
+
+ p = strchr(m->llmnr_hostname, 0);
+ assert(p);
+
+ while (p > m->llmnr_hostname) {
+ if (!strchr("0123456789", p[-1]))
+ break;
+
+ p--;
+ }
+
+ if (*p == 0 || safe_atou64(p, &u) < 0 || u <= 0)
+ u = 1;
+
+ /* Add a random number to the old value. This way we can avoid
+ * that two hosts pick the same hostname, win on IPv4 and lose
+ * on IPv6 (or vice versa), and pick the same hostname
+ * replacement hostname, ad infinitum. We still want the
+ * numbers to go up monotonically, hence we just add a random
+ * value 1..10 */
+
+ random_bytes(&a, sizeof(a));
+ u += 1 + a % 10;
+
+ if (asprintf(&h, "%.*s%" PRIu64, (int) (p - m->llmnr_hostname), m->llmnr_hostname, u) < 0)
+ return -ENOMEM;
+
+ r = dns_name_concat(h, "local", &k);
+ if (r < 0) {
+ free(h);
+ return r;
+ }
+
+ log_info("Hostname conflict, changing published hostname from '%s' to '%s'.", m->llmnr_hostname, h);
+
+ free(m->llmnr_hostname);
+ m->llmnr_hostname = h;
+
+ free(m->mdns_hostname);
+ m->mdns_hostname = k;
+
+ manager_refresh_rrs(m);
+
+ return 0;
+}
+
+LinkAddress* manager_find_link_address(Manager *m, int family, const union in_addr_union *in_addr) {
+ Iterator i;
+ Link *l;
+
+ assert(m);
+
+ HASHMAP_FOREACH(l, m->links, i) {
+ LinkAddress *a;
+
+ a = link_find_address(l, family, in_addr);
+ if (a)
+ return a;
+ }
+
+ return NULL;
+}
+
+bool manager_our_packet(Manager *m, DnsPacket *p) {
+ assert(m);
+ assert(p);
+
+ return !!manager_find_link_address(m, p->family, &p->sender);
+}
+
+DnsScope* manager_find_scope(Manager *m, DnsPacket *p) {
+ Link *l;
+
+ assert(m);
+ assert(p);
+
+ l = hashmap_get(m->links, INT_TO_PTR(p->ifindex));
+ if (!l)
+ return NULL;
+
+ switch (p->protocol) {
+ case DNS_PROTOCOL_LLMNR:
+ if (p->family == AF_INET)
+ return l->llmnr_ipv4_scope;
+ else if (p->family == AF_INET6)
+ return l->llmnr_ipv6_scope;
+
+ break;
+
+ case DNS_PROTOCOL_MDNS:
+ if (p->family == AF_INET)
+ return l->mdns_ipv4_scope;
+ else if (p->family == AF_INET6)
+ return l->mdns_ipv6_scope;
+
+ break;
+
+ default:
+ break;
+ }
+
+ return NULL;
+}
+
+void manager_verify_all(Manager *m) {
+ DnsScope *s;
+
+ assert(m);
+
+ LIST_FOREACH(scopes, s, m->dns_scopes)
+ dns_zone_verify_all(&s->zone);
+}
+
+int manager_is_own_hostname(Manager *m, const char *name) {
+ int r;
+
+ assert(m);
+ assert(name);
+
+ if (m->llmnr_hostname) {
+ r = dns_name_equal(name, m->llmnr_hostname);
+ if (r != 0)
+ return r;
+ }
+
+ if (m->mdns_hostname)
+ return dns_name_equal(name, m->mdns_hostname);
+
+ return 0;
+}
+
+int manager_compile_dns_servers(Manager *m, OrderedSet **dns) {
+ DnsServer *s;
+ Iterator i;
+ Link *l;
+ int r;
+
+ assert(m);
+ assert(dns);
+
+ r = ordered_set_ensure_allocated(dns, &dns_server_hash_ops);
+ if (r < 0)
+ return r;
+
+ /* First add the system-wide servers and domains */
+ LIST_FOREACH(servers, s, m->dns_servers) {
+ r = ordered_set_put(*dns, s);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+
+ /* Then, add the per-link servers */
+ HASHMAP_FOREACH(l, m->links, i) {
+ LIST_FOREACH(servers, s, l->dns_servers) {
+ r = ordered_set_put(*dns, s);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+ }
+
+ /* If we found nothing, add the fallback servers */
+ if (ordered_set_isempty(*dns)) {
+ LIST_FOREACH(servers, s, m->fallback_dns_servers) {
+ r = ordered_set_put(*dns, s);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+ }
+
+ return 0;
+}
+
+/* filter_route is a tri-state:
+ * < 0: no filtering
+ * = 0 or false: return only domains which should be used for searching
+ * > 0 or true: return only domains which are for routing only
+ */
+int manager_compile_search_domains(Manager *m, OrderedSet **domains, int filter_route) {
+ DnsSearchDomain *d;
+ Iterator i;
+ Link *l;
+ int r;
+
+ assert(m);
+ assert(domains);
+
+ r = ordered_set_ensure_allocated(domains, &dns_name_hash_ops);
+ if (r < 0)
+ return r;
+
+ LIST_FOREACH(domains, d, m->search_domains) {
+
+ if (filter_route >= 0 &&
+ d->route_only != !!filter_route)
+ continue;
+
+ r = ordered_set_put(*domains, d->name);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+
+ HASHMAP_FOREACH(l, m->links, i) {
+
+ LIST_FOREACH(domains, d, l->search_domains) {
+
+ if (filter_route >= 0 &&
+ d->route_only != !!filter_route)
+ continue;
+
+ r = ordered_set_put(*domains, d->name);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+ }
+
+ return 0;
+}
+
+DnssecMode manager_get_dnssec_mode(Manager *m) {
+ assert(m);
+
+ if (m->dnssec_mode != _DNSSEC_MODE_INVALID)
+ return m->dnssec_mode;
+
+ return DNSSEC_NO;
+}
+
+bool manager_dnssec_supported(Manager *m) {
+ DnsServer *server;
+ Iterator i;
+ Link *l;
+
+ assert(m);
+
+ if (manager_get_dnssec_mode(m) == DNSSEC_NO)
+ return false;
+
+ server = manager_get_dns_server(m);
+ if (server && !dns_server_dnssec_supported(server))
+ return false;
+
+ HASHMAP_FOREACH(l, m->links, i)
+ if (!link_dnssec_supported(l))
+ return false;
+
+ return true;
+}
+
+void manager_dnssec_verdict(Manager *m, DnssecVerdict verdict, const DnsResourceKey *key) {
+
+ assert(verdict >= 0);
+ assert(verdict < _DNSSEC_VERDICT_MAX);
+
+ if (log_get_max_level() >= LOG_DEBUG) {
+ char s[DNS_RESOURCE_KEY_STRING_MAX];
+
+ log_debug("Found verdict for lookup %s: %s",
+ dns_resource_key_to_string(key, s, sizeof s),
+ dnssec_verdict_to_string(verdict));
+ }
+
+ m->n_dnssec_verdict[verdict]++;
+}
+
+bool manager_routable(Manager *m, int family) {
+ Iterator i;
+ Link *l;
+
+ assert(m);
+
+ /* Returns true if the host has at least one interface with a routable address of the specified type */
+
+ HASHMAP_FOREACH(l, m->links, i)
+ if (link_relevant(l, family, false))
+ return true;
+
+ return false;
+}
+
+void manager_flush_caches(Manager *m) {
+ DnsScope *scope;
+
+ assert(m);
+
+ LIST_FOREACH(scopes, scope, m->dns_scopes)
+ dns_cache_flush(&scope->cache);
+
+ log_info("Flushed all caches.");
+}
+
+void manager_cleanup_saved_user(Manager *m) {
+ _cleanup_closedir_ DIR *d = NULL;
+ struct dirent *de;
+ int r;
+
+ assert(m);
+
+ /* Clean up all saved per-link files in /run/systemd/resolve/netif/ that don't have a matching interface
+ * anymore. These files are created to persist settings pushed in by the user via the bus, so that resolved can
+ * be restarted without losing this data. */
+
+ d = opendir("/run/systemd/resolve/netif/");
+ if (!d) {
+ if (errno == ENOENT)
+ return;
+
+ log_warning_errno(errno, "Failed to open interface directory: %m");
+ return;
+ }
+
+ FOREACH_DIRENT_ALL(de, d, log_error_errno(errno, "Failed to read interface directory: %m")) {
+ _cleanup_free_ char *p = NULL;
+ int ifindex;
+ Link *l;
+
+ if (!IN_SET(de->d_type, DT_UNKNOWN, DT_REG))
+ continue;
+
+ if (STR_IN_SET(de->d_name, ".", ".."))
+ continue;
+
+ r = parse_ifindex(de->d_name, &ifindex);
+ if (r < 0) /* Probably some temporary file from a previous run. Delete it */
+ goto rm;
+
+ l = hashmap_get(m->links, INT_TO_PTR(ifindex));
+ if (!l) /* link vanished */
+ goto rm;
+
+ if (l->is_managed) /* now managed by networkd, hence the bus settings are useless */
+ goto rm;
+
+ continue;
+
+ rm:
+ p = strappend("/run/systemd/resolve/netif/", de->d_name);
+ if (!p) {
+ log_oom();
+ return;
+ }
+
+ (void) unlink(p);
+ }
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-manager.h b/src/grp-resolve/systemd-resolved/resolved-manager.h
new file mode 100644
index 0000000000..2e187efeb5
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-manager.h
@@ -0,0 +1,183 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Tom Gundersen <teg@jklm.no>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <systemd/sd-event.h>
+
+#include "systemd-basic/hashmap.h"
+#include "systemd-basic/list.h"
+#include "systemd-basic/ordered-set.h"
+#include "systemd-shared/resolve-util.h"
+#include "systemd-staging/sd-netlink.h"
+#include "systemd-staging/sd-network.h"
+
+typedef struct Manager Manager;
+
+#include "resolved-dns-query.h"
+#include "resolved-dns-search-domain.h"
+#include "resolved-dns-server.h"
+#include "resolved-dns-stream.h"
+#include "resolved-dns-trust-anchor.h"
+#include "resolved-link.h"
+
+#define MANAGER_SEARCH_DOMAINS_MAX 32
+#define MANAGER_DNS_SERVERS_MAX 32
+
+struct Manager {
+ sd_event *event;
+
+ ResolveSupport llmnr_support;
+ ResolveSupport mdns_support;
+ DnssecMode dnssec_mode;
+ bool enable_cache;
+
+ /* Network */
+ Hashmap *links;
+
+ sd_netlink *rtnl;
+ sd_event_source *rtnl_event_source;
+
+ sd_network_monitor *network_monitor;
+ sd_event_source *network_event_source;
+
+ /* DNS query management */
+ Hashmap *dns_transactions;
+ LIST_HEAD(DnsQuery, dns_queries);
+ unsigned n_dns_queries;
+
+ LIST_HEAD(DnsStream, dns_streams);
+ unsigned n_dns_streams;
+
+ /* Unicast dns */
+ LIST_HEAD(DnsServer, dns_servers);
+ LIST_HEAD(DnsServer, fallback_dns_servers);
+ unsigned n_dns_servers; /* counts both main and fallback */
+ DnsServer *current_dns_server;
+
+ LIST_HEAD(DnsSearchDomain, search_domains);
+ unsigned n_search_domains;
+
+ bool need_builtin_fallbacks:1;
+
+ bool read_resolv_conf:1;
+ usec_t resolv_conf_mtime;
+
+ DnsTrustAnchor trust_anchor;
+
+ LIST_HEAD(DnsScope, dns_scopes);
+ DnsScope *unicast_scope;
+
+ /* LLMNR */
+ int llmnr_ipv4_udp_fd;
+ int llmnr_ipv6_udp_fd;
+ int llmnr_ipv4_tcp_fd;
+ int llmnr_ipv6_tcp_fd;
+
+ sd_event_source *llmnr_ipv4_udp_event_source;
+ sd_event_source *llmnr_ipv6_udp_event_source;
+ sd_event_source *llmnr_ipv4_tcp_event_source;
+ sd_event_source *llmnr_ipv6_tcp_event_source;
+
+ /* mDNS */
+ int mdns_ipv4_fd;
+ int mdns_ipv6_fd;
+
+ sd_event_source *mdns_ipv4_event_source;
+ sd_event_source *mdns_ipv6_event_source;
+
+ /* dbus */
+ sd_bus *bus;
+ sd_event_source *bus_retry_event_source;
+
+ /* The hostname we publish on LLMNR and mDNS */
+ char *llmnr_hostname;
+ char *mdns_hostname;
+ DnsResourceKey *llmnr_host_ipv4_key;
+ DnsResourceKey *llmnr_host_ipv6_key;
+
+ /* Watch the system hostname */
+ int hostname_fd;
+ sd_event_source *hostname_event_source;
+
+ /* Watch for system suspends */
+ sd_bus_slot *prepare_for_sleep_slot;
+
+ sd_event_source *sigusr1_event_source;
+ sd_event_source *sigusr2_event_source;
+
+ unsigned n_transactions_total;
+ unsigned n_dnssec_verdict[_DNSSEC_VERDICT_MAX];
+
+ /* Data from /etc/hosts */
+ Set* etc_hosts_by_address;
+ Hashmap* etc_hosts_by_name;
+ usec_t etc_hosts_last, etc_hosts_mtime;
+
+ /* Local DNS stub on 127.0.0.53:53 */
+ int dns_stub_udp_fd;
+ int dns_stub_tcp_fd;
+
+ sd_event_source *dns_stub_udp_event_source;
+ sd_event_source *dns_stub_tcp_event_source;
+};
+
+/* Manager */
+
+int manager_new(Manager **ret);
+Manager* manager_free(Manager *m);
+
+int manager_start(Manager *m);
+
+uint32_t manager_find_mtu(Manager *m);
+
+int manager_write(Manager *m, int fd, DnsPacket *p);
+int manager_send(Manager *m, int fd, int ifindex, int family, const union in_addr_union *destination, uint16_t port, const union in_addr_union *source, DnsPacket *p);
+int manager_recv(Manager *m, int fd, DnsProtocol protocol, DnsPacket **ret);
+
+int manager_find_ifindex(Manager *m, int family, const union in_addr_union *in_addr);
+LinkAddress* manager_find_link_address(Manager *m, int family, const union in_addr_union *in_addr);
+
+void manager_refresh_rrs(Manager *m);
+int manager_next_hostname(Manager *m);
+
+bool manager_our_packet(Manager *m, DnsPacket *p);
+DnsScope* manager_find_scope(Manager *m, DnsPacket *p);
+
+void manager_verify_all(Manager *m);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_free);
+
+#define EXTRA_CMSG_SPACE 1024
+
+int manager_is_own_hostname(Manager *m, const char *name);
+
+int manager_compile_dns_servers(Manager *m, OrderedSet **servers);
+int manager_compile_search_domains(Manager *m, OrderedSet **domains, int filter_route);
+
+DnssecMode manager_get_dnssec_mode(Manager *m);
+bool manager_dnssec_supported(Manager *m);
+
+void manager_dnssec_verdict(Manager *m, DnssecVerdict verdict, const DnsResourceKey *key);
+
+bool manager_routable(Manager *m, int family);
+
+void manager_flush_caches(Manager *m);
+
+void manager_cleanup_saved_user(Manager *m);
diff --git a/src/grp-resolve/systemd-resolved/resolved-mdns.c b/src/grp-resolve/systemd-resolved/resolved-mdns.c
new file mode 100644
index 0000000000..f810019763
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-mdns.c
@@ -0,0 +1,288 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2015 Daniel Mack
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+ ***/
+
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <resolv.h>
+
+#include "systemd-basic/fd-util.h"
+
+#include "resolved-manager.h"
+#include "resolved-mdns.h"
+
+void manager_mdns_stop(Manager *m) {
+ assert(m);
+
+ m->mdns_ipv4_event_source = sd_event_source_unref(m->mdns_ipv4_event_source);
+ m->mdns_ipv4_fd = safe_close(m->mdns_ipv4_fd);
+
+ m->mdns_ipv6_event_source = sd_event_source_unref(m->mdns_ipv6_event_source);
+ m->mdns_ipv6_fd = safe_close(m->mdns_ipv6_fd);
+}
+
+int manager_mdns_start(Manager *m) {
+ int r;
+
+ assert(m);
+
+ if (m->mdns_support == RESOLVE_SUPPORT_NO)
+ return 0;
+
+ r = manager_mdns_ipv4_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+
+ if (socket_ipv6_is_supported()) {
+ r = manager_mdns_ipv6_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+
+eaddrinuse:
+ log_warning("There appears to be another mDNS responder running. Turning off mDNS support.");
+ m->mdns_support = RESOLVE_SUPPORT_NO;
+ manager_mdns_stop(m);
+
+ return 0;
+}
+
+static int on_mdns_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ Manager *m = userdata;
+ DnsScope *scope;
+ int r;
+
+ r = manager_recv(m, fd, DNS_PROTOCOL_MDNS, &p);
+ if (r <= 0)
+ return r;
+
+ scope = manager_find_scope(m, p);
+ if (!scope) {
+ log_warning("Got mDNS UDP packet on unknown scope. Ignoring.");
+ return 0;
+ }
+
+ if (dns_packet_validate_reply(p) > 0) {
+ DnsResourceRecord *rr;
+
+ log_debug("Got mDNS reply packet");
+
+ /*
+ * mDNS is different from regular DNS and LLMNR with regard to handling responses.
+ * While on other protocols, we can ignore every answer that doesn't match a question
+ * we broadcast earlier, RFC6762, section 18.1 recommends looking at and caching all
+ * incoming information, regardless of the DNS packet ID.
+ *
+ * Hence, extract the packet here, and try to find a transaction for answer the we got
+ * and complete it. Also store the new information in scope's cache.
+ */
+ r = dns_packet_extract(p);
+ if (r < 0) {
+ log_debug("mDNS packet extraction failed.");
+ return 0;
+ }
+
+ dns_scope_check_conflicts(scope, p);
+
+ DNS_ANSWER_FOREACH(rr, p->answer) {
+ const char *name = dns_resource_key_name(rr->key);
+ DnsTransaction *t;
+
+ /* If the received reply packet contains ANY record that is not .local or .in-addr.arpa,
+ * we assume someone's playing tricks on us and discard the packet completely. */
+ if (!(dns_name_endswith(name, "in-addr.arpa") > 0 ||
+ dns_name_endswith(name, "local") > 0))
+ return 0;
+
+ t = dns_scope_find_transaction(scope, rr->key, false);
+ if (t)
+ dns_transaction_process_reply(t, p);
+ }
+
+ dns_cache_put(&scope->cache, NULL, DNS_PACKET_RCODE(p), p->answer, false, (uint32_t) -1, 0, p->family, &p->sender);
+
+ } else if (dns_packet_validate_query(p) > 0) {
+ log_debug("Got mDNS query packet for id %u", DNS_PACKET_ID(p));
+
+ dns_scope_process_query(scope, NULL, p);
+ } else
+ log_debug("Invalid mDNS UDP packet.");
+
+ return 0;
+}
+
+int manager_mdns_ipv4_fd(Manager *m) {
+ union sockaddr_union sa = {
+ .in.sin_family = AF_INET,
+ .in.sin_port = htobe16(MDNS_PORT),
+ };
+ static const int one = 1, pmtu = IP_PMTUDISC_DONT, ttl = 255;
+ int r;
+
+ assert(m);
+
+ if (m->mdns_ipv4_fd >= 0)
+ return m->mdns_ipv4_fd;
+
+ m->mdns_ipv4_fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (m->mdns_ipv4_fd < 0)
+ return -errno;
+
+ r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->mdns_ipv4_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ /* Disable Don't-Fragment bit in the IP header */
+ r = setsockopt(m->mdns_ipv4_fd, IPPROTO_IP, IP_MTU_DISCOVER, &pmtu, sizeof(pmtu));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = bind(m->mdns_ipv4_fd, &sa.sa, sizeof(sa.in));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = sd_event_add_io(m->event, &m->mdns_ipv4_event_source, m->mdns_ipv4_fd, EPOLLIN, on_mdns_packet, m);
+ if (r < 0)
+ goto fail;
+
+ return m->mdns_ipv4_fd;
+
+fail:
+ m->mdns_ipv4_fd = safe_close(m->mdns_ipv4_fd);
+ return r;
+}
+
+int manager_mdns_ipv6_fd(Manager *m) {
+ union sockaddr_union sa = {
+ .in6.sin6_family = AF_INET6,
+ .in6.sin6_port = htobe16(MDNS_PORT),
+ };
+ static const int one = 1, ttl = 255;
+ int r;
+
+ assert(m);
+
+ if (m->mdns_ipv6_fd >= 0)
+ return m->mdns_ipv6_fd;
+
+ m->mdns_ipv6_fd = socket(AF_INET6, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (m->mdns_ipv6_fd < 0)
+ return -errno;
+
+ r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ /* RFC 4795, section 2.5 recommends setting the TTL of UDP packets to 255. */
+ r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->mdns_ipv6_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = setsockopt(m->mdns_ipv6_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = bind(m->mdns_ipv6_fd, &sa.sa, sizeof(sa.in6));
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ r = sd_event_add_io(m->event, &m->mdns_ipv6_event_source, m->mdns_ipv6_fd, EPOLLIN, on_mdns_packet, m);
+ if (r < 0)
+ goto fail;
+
+ return m->mdns_ipv6_fd;
+
+fail:
+ m->mdns_ipv6_fd = safe_close(m->mdns_ipv6_fd);
+ return r;
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-mdns.h b/src/grp-resolve/systemd-resolved/resolved-mdns.h
new file mode 100644
index 0000000000..5d274648f4
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-mdns.h
@@ -0,0 +1,30 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2015 Daniel Mack
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "resolved-manager.h"
+
+#define MDNS_PORT 5353
+
+int manager_mdns_ipv4_fd(Manager *m);
+int manager_mdns_ipv6_fd(Manager *m);
+
+void manager_mdns_stop(Manager *m);
+int manager_mdns_start(Manager *m);
diff --git a/src/grp-resolve/systemd-resolved/resolved-resolv-conf.c b/src/grp-resolve/systemd-resolved/resolved-resolv-conf.c
new file mode 100644
index 0000000000..01b6481016
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-resolv-conf.c
@@ -0,0 +1,267 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Tom Gundersen <teg@jklm.no>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+ ***/
+
+#include <resolv.h>
+
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/fd-util.h"
+#include "systemd-basic/fileio-label.h"
+#include "systemd-basic/fileio.h"
+#include "systemd-basic/ordered-set.h"
+#include "systemd-basic/string-util.h"
+#include "systemd-basic/strv.h"
+#include "systemd-shared/dns-domain.h"
+
+#include "resolved-conf.h"
+#include "resolved-resolv-conf.h"
+
+int manager_read_resolv_conf(Manager *m) {
+ _cleanup_fclose_ FILE *f = NULL;
+ struct stat st, own;
+ char line[LINE_MAX];
+ usec_t t;
+ int r;
+
+ assert(m);
+
+ /* Reads the system /etc/resolv.conf, if it exists and is not
+ * symlinked to our own resolv.conf instance */
+
+ if (!m->read_resolv_conf)
+ return 0;
+
+ r = stat("/etc/resolv.conf", &st);
+ if (r < 0) {
+ if (errno == ENOENT)
+ return 0;
+
+ r = log_warning_errno(errno, "Failed to stat /etc/resolv.conf: %m");
+ goto clear;
+ }
+
+ /* Have we already seen the file? */
+ t = timespec_load(&st.st_mtim);
+ if (t == m->resolv_conf_mtime)
+ return 0;
+
+ /* Is it symlinked to our own file? */
+ if (stat("/run/systemd/resolve/resolv.conf", &own) >= 0 &&
+ st.st_dev == own.st_dev &&
+ st.st_ino == own.st_ino)
+ return 0;
+
+ f = fopen("/etc/resolv.conf", "re");
+ if (!f) {
+ if (errno == ENOENT)
+ return 0;
+
+ r = log_warning_errno(errno, "Failed to open /etc/resolv.conf: %m");
+ goto clear;
+ }
+
+ if (fstat(fileno(f), &st) < 0) {
+ r = log_error_errno(errno, "Failed to stat open file: %m");
+ goto clear;
+ }
+
+ dns_server_mark_all(m->dns_servers);
+ dns_search_domain_mark_all(m->search_domains);
+
+ FOREACH_LINE(line, f, r = -errno; goto clear) {
+ const char *a;
+ char *l;
+
+ l = strstrip(line);
+ if (*l == '#' || *l == ';')
+ continue;
+
+ a = first_word(l, "nameserver");
+ if (a) {
+ r = manager_parse_dns_server_string_and_warn(m, DNS_SERVER_SYSTEM, a);
+ if (r < 0)
+ log_warning_errno(r, "Failed to parse DNS server address '%s', ignoring.", a);
+
+ continue;
+ }
+
+ a = first_word(l, "domain");
+ if (!a) /* We treat "domain" lines, and "search" lines as equivalent, and add both to our list. */
+ a = first_word(l, "search");
+ if (a) {
+ r = manager_parse_search_domains_and_warn(m, a);
+ if (r < 0)
+ log_warning_errno(r, "Failed to parse search domain string '%s', ignoring.", a);
+ }
+ }
+
+ m->resolv_conf_mtime = t;
+
+ /* Flush out all servers and search domains that are still
+ * marked. Those are then ones that didn't appear in the new
+ * /etc/resolv.conf */
+ dns_server_unlink_marked(m->dns_servers);
+ dns_search_domain_unlink_marked(m->search_domains);
+
+ /* Whenever /etc/resolv.conf changes, start using the first
+ * DNS server of it. This is useful to deal with broken
+ * network managing implementations (like NetworkManager),
+ * that when connecting to a VPN place both the VPN DNS
+ * servers and the local ones in /etc/resolv.conf. Without
+ * resetting the DNS server to use back to the first entry we
+ * will continue to use the local one thus being unable to
+ * resolve VPN domains. */
+ manager_set_dns_server(m, m->dns_servers);
+
+ /* Unconditionally flush the cache when /etc/resolv.conf is
+ * modified, even if the data it contained was completely
+ * identical to the previous version we used. We do this
+ * because altering /etc/resolv.conf is typically done when
+ * the network configuration changes, and that should be
+ * enough to flush the global unicast DNS cache. */
+ if (m->unicast_scope)
+ dns_cache_flush(&m->unicast_scope->cache);
+
+ return 0;
+
+clear:
+ dns_server_unlink_all(m->dns_servers);
+ dns_search_domain_unlink_all(m->search_domains);
+ return r;
+}
+
+static void write_resolv_conf_server(DnsServer *s, FILE *f, unsigned *count) {
+ assert(s);
+ assert(f);
+ assert(count);
+
+ if (!dns_server_string(s)) {
+ log_warning("Our of memory, or invalid DNS address. Ignoring server.");
+ return;
+ }
+
+ if (*count == MAXNS)
+ fputs("# Too many DNS servers configured, the following entries may be ignored.\n", f);
+ (*count)++;
+
+ fprintf(f, "nameserver %s\n", dns_server_string(s));
+}
+
+static void write_resolv_conf_search(
+ OrderedSet *domains,
+ FILE *f) {
+ unsigned length = 0, count = 0;
+ Iterator i;
+ char *domain;
+
+ assert(domains);
+ assert(f);
+
+ fputs("search", f);
+
+ ORDERED_SET_FOREACH(domain, domains, i) {
+ if (++count > MAXDNSRCH) {
+ fputs("\n# Too many search domains configured, remaining ones ignored.", f);
+ break;
+ }
+ length += strlen(domain) + 1;
+ if (length > 256) {
+ fputs("\n# Total length of all search domains is too long, remaining ones ignored.", f);
+ break;
+ }
+ fputc(' ', f);
+ fputs(domain, f);
+ }
+
+ fputs("\n", f);
+}
+
+static int write_resolv_conf_contents(FILE *f, OrderedSet *dns, OrderedSet *domains) {
+ Iterator i;
+
+ fputs("# This file is managed by systemd-resolved(8). Do not edit.\n#\n"
+ "# This is a dynamic resolv.conf file for connecting local clients directly to\n"
+ "# all known DNS servers.\n#\n"
+ "# Third party programs must not access this file directly, but only through the\n"
+ "# symlink at /etc/resolv.conf. To manage resolv.conf(5) in a different way,\n"
+ "# replace this symlink by a static file or a different symlink.\n#\n"
+ "# See systemd-resolved.service(8) for details about the supported modes of\n"
+ "# operation for /etc/resolv.conf.\n\n", f);
+
+ if (ordered_set_isempty(dns))
+ fputs("# No DNS servers known.\n", f);
+ else {
+ unsigned count = 0;
+ DnsServer *s;
+
+ ORDERED_SET_FOREACH(s, dns, i)
+ write_resolv_conf_server(s, f, &count);
+ }
+
+ if (!ordered_set_isempty(domains))
+ write_resolv_conf_search(domains, f);
+
+ return fflush_and_check(f);
+}
+
+int manager_write_resolv_conf(Manager *m) {
+
+ _cleanup_ordered_set_free_ OrderedSet *dns = NULL, *domains = NULL;
+ _cleanup_free_ char *temp_path = NULL;
+ _cleanup_fclose_ FILE *f = NULL;
+ int r;
+
+ assert(m);
+
+ /* Read the system /etc/resolv.conf first */
+ (void) manager_read_resolv_conf(m);
+
+ /* Add the full list to a set, to filter out duplicates */
+ r = manager_compile_dns_servers(m, &dns);
+ if (r < 0)
+ return log_warning_errno(r, "Failed to compile list of DNS servers: %m");
+
+ r = manager_compile_search_domains(m, &domains, false);
+ if (r < 0)
+ return log_warning_errno(r, "Failed to compile list of search domains: %m");
+
+ r = fopen_temporary_label(PRIVATE_RESOLV_CONF, PRIVATE_RESOLV_CONF, &f, &temp_path);
+ if (r < 0)
+ return log_warning_errno(r, "Failed to open private resolv.conf file for writing: %m");
+
+ (void) fchmod(fileno(f), 0644);
+
+ r = write_resolv_conf_contents(f, dns, domains);
+ if (r < 0) {
+ log_error_errno(r, "Failed to write private resolv.conf contents: %m");
+ goto fail;
+ }
+
+ if (rename(temp_path, PRIVATE_RESOLV_CONF) < 0) {
+ r = log_error_errno(errno, "Failed to move private resolv.conf file into place: %m");
+ goto fail;
+ }
+
+ return 0;
+
+fail:
+ (void) unlink(PRIVATE_RESOLV_CONF);
+ (void) unlink(temp_path);
+
+ return r;
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved-resolv-conf.h b/src/grp-resolve/systemd-resolved/resolved-resolv-conf.h
new file mode 100644
index 0000000000..75fa080e4c
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved-resolv-conf.h
@@ -0,0 +1,27 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Tom Gundersen <teg@jklm.no>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "resolved-manager.h"
+
+#define PRIVATE_RESOLV_CONF "/run/systemd/resolve/resolv.conf"
+
+int manager_read_resolv_conf(Manager *m);
+int manager_write_resolv_conf(Manager *m);
diff --git a/src/grp-resolve/systemd-resolved/resolved.c b/src/grp-resolve/systemd-resolved/resolved.c
new file mode 100644
index 0000000000..7fe9b7edbb
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved.c
@@ -0,0 +1,121 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Tom Gundersen <teg@jklm.no>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <systemd/sd-daemon.h>
+#include <systemd/sd-event.h>
+
+#include "systemd-basic/capability-util.h"
+#include "systemd-basic/mkdir.h"
+#include "systemd-basic/selinux-util.h"
+#include "systemd-basic/signal-util.h"
+#include "systemd-basic/user-util.h"
+
+#include "resolved-conf.h"
+#include "resolved-manager.h"
+#include "resolved-resolv-conf.h"
+
+int main(int argc, char *argv[]) {
+ _cleanup_(manager_freep) Manager *m = NULL;
+ const char *user = "systemd-resolve";
+ uid_t uid;
+ gid_t gid;
+ int r;
+
+ log_set_target(LOG_TARGET_AUTO);
+ log_parse_environment();
+ log_open();
+
+ if (argc != 1) {
+ log_error("This program takes no arguments.");
+ r = -EINVAL;
+ goto finish;
+ }
+
+ umask(0022);
+
+ r = mac_selinux_init();
+ if (r < 0) {
+ log_error_errno(r, "SELinux setup failed: %m");
+ goto finish;
+ }
+
+ r = get_user_creds(&user, &uid, &gid, NULL, NULL);
+ if (r < 0) {
+ log_error_errno(r, "Cannot resolve user name %s: %m", user);
+ goto finish;
+ }
+
+ /* Always create the directory where resolv.conf will live */
+ r = mkdir_safe_label("/run/systemd/resolve", 0755, uid, gid);
+ if (r < 0) {
+ log_error_errno(r, "Could not create runtime directory: %m");
+ goto finish;
+ }
+
+ /* Drop privileges, but keep three caps. Note that we drop those too, later on (see below) */
+ r = drop_privileges(uid, gid,
+ (UINT64_C(1) << CAP_NET_RAW)| /* needed for SO_BINDTODEVICE */
+ (UINT64_C(1) << CAP_NET_BIND_SERVICE)| /* needed to bind on port 53 */
+ (UINT64_C(1) << CAP_SETPCAP) /* needed in order to drop the caps later */);
+ if (r < 0)
+ goto finish;
+
+ assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGTERM, SIGINT, SIGUSR1, SIGUSR2, -1) >= 0);
+
+ r = manager_new(&m);
+ if (r < 0) {
+ log_error_errno(r, "Could not create manager: %m");
+ goto finish;
+ }
+
+ r = manager_start(m);
+ if (r < 0) {
+ log_error_errno(r, "Failed to start manager: %m");
+ goto finish;
+ }
+
+ /* Write finish default resolv.conf to avoid a dangling symlink */
+ (void) manager_write_resolv_conf(m);
+
+ /* Let's drop the remaining caps now */
+ r = capability_bounding_set_drop(0, true);
+ if (r < 0) {
+ log_error_errno(r, "Failed to drop remaining caps: %m");
+ goto finish;
+ }
+
+ sd_notify(false,
+ "READY=1\n"
+ "STATUS=Processing requests...");
+
+ r = sd_event_loop(m->event);
+ if (r < 0) {
+ log_error_errno(r, "Event loop failed: %m");
+ goto finish;
+ }
+
+ sd_event_get_exit_code(m->event, &r);
+
+finish:
+ sd_notify(false,
+ "STOPPING=1\n"
+ "STATUS=Shutting down...");
+
+ return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+}
diff --git a/src/grp-resolve/systemd-resolved/resolved.conf.in b/src/grp-resolve/systemd-resolved/resolved.conf.in
new file mode 100644
index 0000000000..3bd8389c88
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved.conf.in
@@ -0,0 +1,20 @@
+# This file is part of systemd.
+#
+# systemd is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation; either version 2.1 of the License, or
+# (at your option) any later version.
+#
+# Entries in this file show the compile time defaults.
+# You can change settings by editing this file.
+# Defaults can be restored by simply deleting this file.
+#
+# See resolved.conf(5) for details
+
+[Resolve]
+#DNS=
+#FallbackDNS=@DNS_SERVERS@
+#Domains=
+#LLMNR=yes
+#DNSSEC=@DEFAULT_DNSSEC_MODE@
+#Cache=yes
diff --git a/src/grp-resolve/systemd-resolved/resolved.conf.xml b/src/grp-resolve/systemd-resolved/resolved.conf.xml
new file mode 100644
index 0000000000..7556c6ff31
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/resolved.conf.xml
@@ -0,0 +1,230 @@
+<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+ "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+
+<!--
+ This file is part of systemd.
+
+ Copyright 2014 Tom Gundersen
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="resolved.conf" conditional='ENABLE_RESOLVED'
+ xmlns:xi="http://www.w3.org/2001/XInclude">
+ <refentryinfo>
+ <title>resolved.conf</title>
+ <productname>systemd</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Tom</firstname>
+ <surname>Gundersen</surname>
+ <email>teg@jklm.no</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>resolved.conf</refentrytitle>
+ <manvolnum>5</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>resolved.conf</refname>
+ <refname>resolved.conf.d</refname>
+ <refpurpose>Network Name Resolution configuration files</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <para><filename>/etc/systemd/resolved.conf</filename></para>
+ <para><filename>/etc/systemd/resolved.conf.d/*.conf</filename></para>
+ <para><filename>/run/systemd/resolved.conf.d/*.conf</filename></para>
+ <para><filename>/usr/lib/systemd/resolved.conf.d/*.conf</filename></para>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para>These configuration files control local DNS and LLMNR
+ name resolution.</para>
+
+ </refsect1>
+
+ <xi:include href="standard-conf.xml" xpointer="main-conf" />
+
+ <refsect1>
+ <title>Options</title>
+
+ <para>The following options are available in the <literal>[Resolve]</literal> section:</para>
+
+ <variablelist class='network-directives'>
+
+ <varlistentry>
+ <term><varname>DNS=</varname></term>
+ <listitem><para>A space-separated list of IPv4 and IPv6 addresses to use as system DNS servers. DNS requests
+ are sent to one of the listed DNS servers in parallel to suitable per-link DNS servers acquired from
+ <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> or
+ set at runtime by external applications. For compatibility reasons, if this setting is not specified, the DNS
+ servers listed in <filename>/etc/resolv.conf</filename> are used instead, if that file exists and any servers
+ are configured in it. This setting defaults to the empty list.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>FallbackDNS=</varname></term>
+ <listitem><para>A space-separated list of IPv4 and IPv6 addresses to use as the fallback DNS servers. Any
+ per-link DNS servers obtained from
+ <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ take precedence over this setting, as do any servers set via <varname>DNS=</varname> above or
+ <filename>/etc/resolv.conf</filename>. This setting is hence only used if no other DNS server information is
+ known. If this option is not given, a compiled-in list of DNS servers is used instead.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>Domains=</varname></term>
+ <listitem><para>A space-separated list of domains. These domains are used as search suffixes when resolving
+ single-label host names (domain names which contain no dot), in order to qualify them into fully-qualified
+ domain names (FQDNs). Search domains are strictly processed in the order they are specified, until the name
+ with the suffix appended is found. For compatibility reasons, if this setting is not specified, the search
+ domains listed in <filename>/etc/resolv.conf</filename> are used instead, if that file exists and any domains
+ are configured in it. This setting defaults to the empty list.</para>
+
+ <para>Specified domain names may optionally be prefixed with <literal>~</literal>. In this case they do not
+ define a search path, but preferably direct DNS queries for the indicated domains to the DNS servers configured
+ with the system <varname>DNS=</varname> setting (see above), in case additional, suitable per-link DNS servers
+ are known. If no per-link DNS servers are known using the <literal>~</literal> syntax has no effect. Use the
+ construct <literal>~.</literal> (which is composed of <literal>~</literal> to indicate a routing domain and
+ <literal>.</literal> to indicate the DNS root domain that is the implied suffix of all DNS domains) to use the
+ system DNS server defined with <varname>DNS=</varname> preferably for all domains.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>LLMNR=</varname></term>
+ <listitem><para>Takes a boolean argument or
+ <literal>resolve</literal>. Controls Link-Local Multicast Name
+ Resolution support (<ulink
+ url="https://tools.ietf.org/html/rfc4795">RFC 4794</ulink>) on
+ the local host. If true, enables full LLMNR responder and
+ resolver support. If false, disables both. If set to
+ <literal>resolve</literal>, only resolution support is enabled,
+ but responding is disabled. Note that
+ <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ also maintains per-link LLMNR settings. LLMNR will be
+ enabled on a link only if the per-link and the
+ global setting is on.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>DNSSEC=</varname></term>
+ <listitem><para>Takes a boolean argument or
+ <literal>allow-downgrade</literal>. If true all DNS lookups are
+ DNSSEC-validated locally (excluding LLMNR and Multicast
+ DNS). If the response to a lookup request is detected to be invalid
+ a lookup failure is returned to applications. Note that
+ this mode requires a DNS server that supports DNSSEC. If the
+ DNS server does not properly support DNSSEC all validations
+ will fail. If set to <literal>allow-downgrade</literal> DNSSEC
+ validation is attempted, but if the server does not support
+ DNSSEC properly, DNSSEC mode is automatically disabled. Note
+ that this mode makes DNSSEC validation vulnerable to
+ "downgrade" attacks, where an attacker might be able to
+ trigger a downgrade to non-DNSSEC mode by synthesizing a DNS
+ response that suggests DNSSEC was not supported. If set to
+ false, DNS lookups are not DNSSEC validated.</para>
+
+ <para>Note that DNSSEC validation requires retrieval of
+ additional DNS data, and thus results in a small DNS look-up
+ time penalty.</para>
+
+ <para>DNSSEC requires knowledge of "trust anchors" to prove
+ data integrity. The trust anchor for the Internet root domain
+ is built into the resolver, additional trust anchors may be
+ defined with
+ <citerefentry><refentrytitle>dnssec-trust-anchors.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
+ Trust anchors may change at regular intervals, and old trust
+ anchors may be revoked. In such a case DNSSEC validation is
+ not possible until new trust anchors are configured locally or
+ the resolver software package is updated with the new root
+ trust anchor. In effect, when the built-in trust anchor is
+ revoked and <varname>DNSSEC=</varname> is true, all further
+ lookups will fail, as it cannot be proved anymore whether
+ lookups are correctly signed, or validly unsigned. If
+ <varname>DNSSEC=</varname> is set to
+ <literal>allow-downgrade</literal> the resolver will
+ automatically turn off DNSSEC validation in such a case.</para>
+
+ <para>Client programs looking up DNS data will be informed
+ whether lookups could be verified using DNSSEC, or whether the
+ returned data could not be verified (either because the data
+ was found unsigned in the DNS, or the DNS server did not
+ support DNSSEC or no appropriate trust anchors were known). In
+ the latter case it is assumed that client programs employ a
+ secondary scheme to validate the returned DNS data, should
+ this be required.</para>
+
+ <para>It is recommended to set <varname>DNSSEC=</varname> to
+ true on systems where it is known that the DNS server supports
+ DNSSEC correctly, and where software or trust anchor updates
+ happen regularly. On other systems it is recommended to set
+ <varname>DNSSEC=</varname> to
+ <literal>allow-downgrade</literal>.</para>
+
+ <para>In addition to this global DNSSEC setting
+ <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ also maintains per-link DNSSEC settings. For system DNS
+ servers (see above), only the global DNSSEC setting is in
+ effect. For per-link DNS servers the per-link
+ setting is in effect, unless it is unset in which case the
+ global setting is used instead.</para>
+
+ <para>Site-private DNS zones generally conflict with DNSSEC
+ operation, unless a negative (if the private zone is not
+ signed) or positive (if the private zone is signed) trust
+ anchor is configured for them. If
+ <literal>allow-downgrade</literal> mode is selected, it is
+ attempted to detect site-private DNS zones using top-level
+ domains (TLDs) that are not known by the DNS root server. This
+ logic does not work in all private zone setups.</para>
+
+ <para>Defaults to off.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>Cache=</varname></term>
+ <listitem><para>Takes a boolean argument. If "yes" (the default), resolving a domain name which already got
+ queried earlier will return the previous result as long as it is still valid, and thus does not result in a new
+ network request. Be aware that that turning off caching comes at a performance penalty, which is particularly
+ high when DNSSEC is used.</para>
+
+ <para>Note that caching is turned off implicitly if the configured DNS server is on a host-local IP address
+ (such as 127.0.0.1 or ::1), in order to avoid duplicate local caching.</para></listitem>
+ </varlistentry>
+
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-resolved.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>dnssec-trust-anchors.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>resolv.conf</refentrytitle><manvolnum>4</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
diff --git a/src/grp-resolve/systemd-resolved/systemd-resolved.service.m4.in b/src/grp-resolve/systemd-resolved/systemd-resolved.service.m4.in
new file mode 100644
index 0000000000..15ab56a066
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/systemd-resolved.service.m4.in
@@ -0,0 +1,34 @@
+# This file is part of systemd.
+#
+# systemd is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation; either version 2.1 of the License, or
+# (at your option) any later version.
+
+[Unit]
+Description=Network Name Resolution
+Documentation=man:systemd-resolved.service(8)
+Documentation=http://www.freedesktop.org/wiki/Software/systemd/resolved
+Documentation=http://www.freedesktop.org/wiki/Software/systemd/writing-network-configuration-managers
+Documentation=http://www.freedesktop.org/wiki/Software/systemd/writing-resolver-clients
+After=systemd-networkd.service network.target
+
+# On kdbus systems we pull in the busname explicitly, because it
+# carries policy that allows the daemon to acquire its name.
+Wants=org.freedesktop.resolve1.busname
+After=org.freedesktop.resolve1.busname
+
+[Service]
+Type=notify
+Restart=always
+RestartSec=0
+ExecStart=@rootlibexecdir@/systemd-resolved
+CapabilityBoundingSet=CAP_SETUID CAP_SETGID CAP_SETPCAP CAP_CHOWN CAP_DAC_OVERRIDE CAP_FOWNER CAP_NET_RAW CAP_NET_BIND_SERVICE
+ProtectSystem=full
+ProtectHome=yes
+WatchdogSec=3min
+MemoryDenyWriteExecute=yes
+SystemCallFilter=~@clock @cpu-emulation @debug @keyring @module @mount @obsolete @raw-io
+
+[Install]
+WantedBy=multi-user.target
diff --git a/src/grp-resolve/systemd-resolved/systemd-resolved.service.xml b/src/grp-resolve/systemd-resolved/systemd-resolved.service.xml
new file mode 100644
index 0000000000..aa1c2365e5
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/systemd-resolved.service.xml
@@ -0,0 +1,234 @@
+<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+ "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+
+<!--
+ This file is part of systemd.
+
+ Copyright 2014 Tom Gundersen
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="systemd-resolved.service" conditional='ENABLE_RESOLVED'>
+
+ <refentryinfo>
+ <title>systemd-resolved.service</title>
+ <productname>systemd</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Tom</firstname>
+ <surname>Gundersen</surname>
+ <email>teg@jklm.no</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>systemd-resolved.service</refentrytitle>
+ <manvolnum>8</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>systemd-resolved.service</refname>
+ <refname>systemd-resolved</refname>
+ <refpurpose>Network Name Resolution manager</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <para><filename>systemd-resolved.service</filename></para>
+ <para><filename>/usr/lib/systemd/systemd-resolved</filename></para>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><command>systemd-resolved</command> is a system service that provides network name resolution to local
+ applications. It implements a caching and validating DNS/DNSSEC stub resolver, as well as an LLMNR resolver and
+ responder. Local applications may submit network name resolution requests via three interfaces:</para>
+
+ <itemizedlist>
+ <listitem><para>The native, fully-featured API <command>systemd-resolved</command> exposes on the bus. See the
+ <ulink url="http://www.freedesktop.org/wiki/Software/systemd/resolved">API Documentation</ulink> for
+ details. Usage of this API is generally recommended to clients as it is asynchronous and fully featured (for
+ example, properly returns DNSSEC validation status and interface scope for addresses as necessary for supporting
+ link-local networking).</para></listitem>
+
+ <listitem><para>The glibc
+ <citerefentry><refentrytitle>getaddrinfo</refentrytitle><manvolnum>3</manvolnum></citerefentry> API as defined
+ by <ulink url="https://tools.ietf.org/html/rfc3493">RFC3493</ulink> and its related resolver functions,
+ including <citerefentry><refentrytitle>gethostbyname</refentrytitle><manvolnum>3</manvolnum></citerefentry>. This
+ API is widely supported, including beyond the Linux platform. In its current form it does not expose DNSSEC
+ validation status information however, and is synchronous only. This API is backed by the glibc Name Service
+ Switch (<citerefentry><refentrytitle>nss</refentrytitle><manvolnum>5</manvolnum></citerefentry>). Usage of the
+ glibc NSS module <citerefentry><refentrytitle>nss-resolve</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ is required in order to allow glibc's NSS resolver functions to resolve host names via
+ <command>systemd-resolved</command>.</para></listitem>
+
+ <listitem><para>Additionally, <command>systemd-resolved</command> provides a local DNS stub listener on IP
+ address 127.0.0.53 on the local loopback interface. Programs issuing DNS requests directly, bypassing any local
+ API may be directed to this stub, in order to connect them to <command>systemd-resolved</command>. Note however
+ that it is strongly recommended that local programs use the glibc NSS or bus APIs instead (as described above),
+ as various network resolution concepts (such as link-local addressing, or LLMNR Unicode domains) cannot be mapped
+ to the unicast DNS protocol.</para></listitem>
+ </itemizedlist>
+
+ <para>The DNS servers contacted are determined from the global settings in
+ <filename>/etc/systemd/resolved.conf</filename>, the per-link static settings in
+ <filename>/etc/systemd/network/*.network</filename> files, the per-link dynamic settings received over DHCP and any
+ DNS server information made available by other system services. See
+ <citerefentry><refentrytitle>resolved.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> and
+ <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry> for details
+ about systemd's own configuration files for DNS servers. To improve compatibility,
+ <filename>/etc/resolv.conf</filename> is read in order to discover configured system DNS servers, but only if it is
+ not a symlink to <filename>/run/systemd/resolve/resolv.conf</filename> (see below).</para>
+
+ <para><command>systemd-resolved</command> synthesizes DNS resource records (RRs) for the following cases:</para>
+
+ <itemizedlist>
+ <listitem><para>The local, configured hostname is resolved to
+ all locally configured IP addresses ordered by their scope, or
+ — if none are configured — the IPv4 address 127.0.0.2 (which
+ is on the local loopback) and the IPv6 address ::1 (which is the
+ local host).</para></listitem>
+
+ <listitem><para>The hostnames <literal>localhost</literal> and
+ <literal>localhost.localdomain</literal> (as well as any hostname
+ ending in <literal>.localhost</literal> or <literal>.localhost.localdomain</literal>)
+ are resolved to the IP addresses 127.0.0.1 and ::1.</para></listitem>
+
+ <listitem><para>The hostname <literal>gateway</literal> is
+ resolved to all current default routing gateway addresses,
+ ordered by their metric. This assigns a stable hostname to the
+ current gateway, useful for referencing it independently of the
+ current network configuration state.</para></listitem>
+
+ <listitem><para>The mappings defined in <filename>/etc/hosts</filename> are resolved to their configured
+ addresses and back.</para></listitem>
+ </itemizedlist>
+
+ <para>Lookup requests are routed to the available DNS servers
+ and LLMNR interfaces according to the following rules:</para>
+
+ <itemizedlist>
+ <listitem><para>Lookups for the special hostname
+ <literal>localhost</literal> are never routed to the
+ network. (A few other, special domains are handled the same way.)</para></listitem>
+
+ <listitem><para>Single-label names are routed to all local
+ interfaces capable of IP multicasting, using the LLMNR
+ protocol. Lookups for IPv4 addresses are only sent via LLMNR on
+ IPv4, and lookups for IPv6 addresses are only sent via LLMNR on
+ IPv6. Lookups for the locally configured host name and the
+ <literal>gateway</literal> host name are never routed to
+ LLMNR.</para></listitem>
+
+ <listitem><para>Multi-label names are routed to all local
+ interfaces that have a DNS sever configured, plus the globally
+ configured DNS server if there is one. Address lookups from the
+ link-local address range are never routed to
+ DNS.</para></listitem>
+ </itemizedlist>
+
+ <para>If lookups are routed to multiple interfaces, the first
+ successful response is returned (thus effectively merging the
+ lookup zones on all matching interfaces). If the lookup failed on
+ all interfaces, the last failing response is returned.</para>
+
+ <para>Routing of lookups may be influenced by configuring
+ per-interface domain names. See
+ <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ for details. Lookups for a hostname ending in one of the
+ per-interface domains are exclusively routed to the matching
+ interfaces.</para>
+
+ <para>See the <ulink url="http://www.freedesktop.org/wiki/Software/systemd/resolved"> resolved D-Bus API
+ Documentation</ulink> for information about the APIs <filename>systemd-resolved</filename> provides.</para>
+
+ </refsect1>
+
+ <refsect1>
+ <title><filename>/etc/resolv.conf</filename></title>
+
+ <para>Three modes of handling <filename>/etc/resolv.conf</filename> (see
+ <citerefentry><refentrytitle>resolv.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>) are
+ supported:</para>
+
+ <itemizedlist>
+ <listitem><para>A static file <filename>/usr/lib/systemd/resolv.conf</filename> is provided that lists
+ the 127.0.0.53 DNS stub (see above) as only DNS server. This file may be symlinked from
+ <filename>/etc/resolv.conf</filename> in order to connect all local clients that bypass local DNS APIs to
+ <command>systemd-resolved</command>. This mode of operation is recommended.</para></listitem>
+
+ <listitem><para><command>systemd-resolved</command> maintains the
+ <filename>/run/systemd/resolve/resolv.conf</filename> file for compatibility with traditional Linux
+ programs. This file may be symlinked from <filename>/etc/resolv.conf</filename> and is always kept up-to-date,
+ containing information about all known DNS servers. Note the file format's limitations: it does not know a
+ concept of per-interface DNS servers and hence only contains system-wide DNS server definitions. Note that
+ <filename>/run/systemd/resolve/resolv.conf</filename> should not be used directly by applications, but only
+ through a symlink from <filename>/etc/resolv.conf</filename>. If this mode of operation is used local clients
+ that bypass any local DNS API will also bypass <command>systemd-resolved</command> and will talk directly to the
+ known DNS servers.</para> </listitem>
+
+ <listitem><para>Alternatively, <filename>/etc/resolv.conf</filename> may be managed by other packages, in which
+ case <command>systemd-resolved</command> will read it for DNS configuration data. In this mode of operation
+ <command>systemd-resolved</command> is consumer rather than provider of this configuration
+ file. </para></listitem>
+ </itemizedlist>
+
+ <para>Note that the selected mode of operation for this file is detected fully automatically, depending on whether
+ <filename>/etc/resolv.conf</filename> is a symlink to <filename>/run/systemd/resolve/resolv.conf</filename> or
+ lists 127.0.0.53 as DNS server.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Signals</title>
+
+ <variablelist>
+ <varlistentry>
+ <term><constant>SIGUSR1</constant></term>
+
+ <listitem><para>Upon reception of the SIGUSR1 process signal <command>systemd-resolved</command> will dump the
+ contents of all DNS resource record caches it maintains into the system logs.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>SIGUSR2</constant></term>
+
+ <listitem><para>Upon reception of the SIGUSR2 process signal <command>systemd-resolved</command> will flush all
+ caches it maintains. Note that it should normally not be necessary to request this explicitly – except for
+ debugging purposes – as <command>systemd-resolved</command> flushes the caches automatically anyway any time
+ the host's network configuration changes.</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>resolved.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>dnssec-trust-anchors.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>nss-resolve</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-resolve</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>resolv.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>hosts</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
diff --git a/src/grp-resolve/systemd-resolved/systemd-resolved.sysusers b/src/grp-resolve/systemd-resolved/systemd-resolved.sysusers
new file mode 100644
index 0000000000..5872bf2db7
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/systemd-resolved.sysusers
@@ -0,0 +1,8 @@
+# This file is part of systemd.
+#
+# systemd is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation; either version 2.1 of the License, or
+# (at your option) any later version.
+
+u systemd-resolve - "systemd Resolver"
diff --git a/src/grp-resolve/systemd-resolved/systemd-resolved.tmpfiles b/src/grp-resolve/systemd-resolved/systemd-resolved.tmpfiles
new file mode 100644
index 0000000000..760fe11412
--- /dev/null
+++ b/src/grp-resolve/systemd-resolved/systemd-resolved.tmpfiles
@@ -0,0 +1,10 @@
+# This file is part of systemd.
+#
+# systemd is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation; either version 2.1 of the License, or
+# (at your option) any later version.
+
+# See tmpfiles.d(5) for details
+
+L! /etc/resolv.conf - - - - ../usr/lib/systemd/resolv.conf