diff options
| -rw-r--r-- | Makefile.am | 2 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-packet.c | 42 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-packet.h | 14 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-scope.c | 9 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-transaction.c | 5 | ||||
| -rw-r--r-- | src/resolve/resolved-llmnr.c | 473 | ||||
| -rw-r--r-- | src/resolve/resolved-llmnr.h | 34 | ||||
| -rw-r--r-- | src/resolve/resolved-manager.c | 448 | ||||
| -rw-r--r-- | src/resolve/resolved-manager.h | 4 |
9 files changed, 557 insertions, 474 deletions
diff --git a/Makefile.am b/Makefile.am index e178bdcb99..c038fed36b 100644 --- a/Makefile.am +++ b/Makefile.am @@ -5102,6 +5102,8 @@ systemd_resolved_SOURCES = \ src/resolve/resolved-bus.h \ src/resolve/resolved-link.h \ src/resolve/resolved-link.c \ + src/resolve/resolved-llmnr.h \ + src/resolve/resolved-llmnr.c \ src/resolve/resolved-def.h \ src/resolve/resolved-dns-rr.h \ src/resolve/resolved-dns-rr.c \ diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c index 47cc9751ed..fa0516f8a0 100644 --- a/src/resolve/resolved-dns-packet.c +++ b/src/resolve/resolved-dns-packet.c @@ -166,10 +166,17 @@ int dns_packet_validate_reply(DnsPacket *p) { if (DNS_PACKET_OPCODE(p) != 0) return -EBADMSG; - /* RFC 4795, Section 2.1.1. says to discard all replies with QDCOUNT != 1 */ - if (p->protocol == DNS_PROTOCOL_LLMNR && - DNS_PACKET_QDCOUNT(p) != 1) - return -EBADMSG; + switch (p->protocol) { + case DNS_PROTOCOL_LLMNR: + /* RFC 4795, Section 2.1.1. says to discard all replies with QDCOUNT != 1 */ + if (DNS_PACKET_QDCOUNT(p) != 1) + return -EBADMSG; + + break; + + default: + break; + } return 1; } @@ -192,18 +199,25 @@ int dns_packet_validate_query(DnsPacket *p) { if (DNS_PACKET_TC(p)) return -EBADMSG; - /* RFC 4795, Section 2.1.1. says to discard all queries with QDCOUNT != 1 */ - if (p->protocol == DNS_PROTOCOL_LLMNR && - DNS_PACKET_QDCOUNT(p) != 1) - return -EBADMSG; + switch (p->protocol) { + case DNS_PROTOCOL_LLMNR: + /* RFC 4795, Section 2.1.1. says to discard all queries with QDCOUNT != 1 */ + if (DNS_PACKET_QDCOUNT(p) != 1) + return -EBADMSG; - /* RFC 4795, Section 2.1.1. says to discard all queries with ANCOUNT != 0 */ - if (DNS_PACKET_ANCOUNT(p) > 0) - return -EBADMSG; + /* RFC 4795, Section 2.1.1. says to discard all queries with ANCOUNT != 0 */ + if (DNS_PACKET_ANCOUNT(p) > 0) + return -EBADMSG; - /* RFC 4795, Section 2.1.1. says to discard all queries with NSCOUNT != 0 */ - if (DNS_PACKET_NSCOUNT(p) > 0) - return -EBADMSG; + /* RFC 4795, Section 2.1.1. says to discard all queries with NSCOUNT != 0 */ + if (DNS_PACKET_NSCOUNT(p) > 0) + return -EBADMSG; + + break; + + default: + break; + } return 1; } diff --git a/src/resolve/resolved-dns-packet.h b/src/resolve/resolved-dns-packet.h index c5867386c6..bf998aa84e 100644 --- a/src/resolve/resolved-dns-packet.h +++ b/src/resolve/resolved-dns-packet.h @@ -99,10 +99,18 @@ static inline uint8_t* DNS_PACKET_DATA(DnsPacket *p) { #define DNS_PACKET_ID(p) DNS_PACKET_HEADER(p)->id #define DNS_PACKET_QR(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 15) & 1) #define DNS_PACKET_OPCODE(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 11) & 15) -#define DNS_PACKET_RCODE(p) (be16toh(DNS_PACKET_HEADER(p)->flags) & 15) +#define DNS_PACKET_AA(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 10) & 1) #define DNS_PACKET_TC(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 9) & 1) -#define DNS_PACKET_C(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 10) & 1) -#define DNS_PACKET_T(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 8) & 1) +#define DNS_PACKET_RD(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 8) & 1) +#define DNS_PACKET_RA(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 7) & 1) +#define DNS_PACKET_AD(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 5) & 1) +#define DNS_PACKET_CD(p) ((be16toh(DNS_PACKET_HEADER(p)->flags) >> 4) & 1) +#define DNS_PACKET_RCODE(p) (be16toh(DNS_PACKET_HEADER(p)->flags) & 15) + +/* LLMNR defines some bits differently */ +#define DNS_PACKET_LLMNR_C(p) DNS_PACKET_AA(p) +#define DNS_PACKET_LLMNR_T(p) DNS_PACKET_RD(p) + #define DNS_PACKET_QDCOUNT(p) be16toh(DNS_PACKET_HEADER(p)->qdcount) #define DNS_PACKET_ANCOUNT(p) be16toh(DNS_PACKET_HEADER(p)->ancount) #define DNS_PACKET_NSCOUNT(p) be16toh(DNS_PACKET_HEADER(p)->nscount) diff --git a/src/resolve/resolved-dns-scope.c b/src/resolve/resolved-dns-scope.c index c25ac2216d..25392d21d7 100644 --- a/src/resolve/resolved-dns-scope.c +++ b/src/resolve/resolved-dns-scope.c @@ -28,6 +28,7 @@ #include "random-util.h" #include "hostname-util.h" #include "dns-domain.h" +#include "resolved-llmnr.h" #include "resolved-dns-scope.h" #define MULTICAST_RATELIMIT_INTERVAL_USEC (1*USEC_PER_SEC) @@ -180,7 +181,7 @@ int dns_scope_emit(DnsScope *s, DnsPacket *p) { return -EBUSY; family = s->family; - port = 5355; + port = LLMNR_PORT; if (family == AF_INET) { addr.in = LLMNR_MULTICAST_IPV4_ADDRESS; @@ -546,7 +547,7 @@ void dns_scope_process_query(DnsScope *s, DnsStream *stream, DnsPacket *p) { return; } - if (DNS_PACKET_C(p)) { + if (DNS_PACKET_LLMNR_C(p)) { /* Somebody notified us about a possible conflict */ dns_scope_verify_conflicts(s, p); return; @@ -760,10 +761,10 @@ void dns_scope_check_conflicts(DnsScope *scope, DnsPacket *p) { if (DNS_PACKET_RRCOUNT(p) <= 0) return; - if (DNS_PACKET_C(p) != 0) + if (DNS_PACKET_LLMNR_C(p) != 0) return; - if (DNS_PACKET_T(p) != 0) + if (DNS_PACKET_LLMNR_T(p) != 0) return; if (manager_our_packet(scope->manager, p)) diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c index 214938986d..3f4673df7a 100644 --- a/src/resolve/resolved-dns-transaction.c +++ b/src/resolve/resolved-dns-transaction.c @@ -21,6 +21,7 @@ #include "af-list.h" +#include "resolved-llmnr.h" #include "resolved-dns-transaction.h" #include "random-util.h" @@ -264,7 +265,7 @@ static int dns_transaction_open_tcp(DnsTransaction *t) { if (r == 0) return -EINVAL; - fd = dns_scope_tcp_socket(t->scope, family, &address, 5355); + fd = dns_scope_tcp_socket(t->scope, family, &address, LLMNR_PORT); } } else return -EAFNOSUPPORT; @@ -323,7 +324,7 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) { /* Tentative packets are not full responses but still * useful for identifying uniqueness conflicts during * probing. */ - if (DNS_PACKET_T(p)) { + if (DNS_PACKET_LLMNR_T(p)) { dns_transaction_tentative(t, p); return; } diff --git a/src/resolve/resolved-llmnr.c b/src/resolve/resolved-llmnr.c new file mode 100644 index 0000000000..8afaf8db6e --- /dev/null +++ b/src/resolve/resolved-llmnr.c @@ -0,0 +1,473 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + 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 <netinet/in.h> + +#include "resolved-manager.h" +#include "resolved-llmnr.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 == 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 = 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; + + 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."); + return 0; + } + + if (dns_packet_validate_reply(p) > 0) { + log_debug("Got LLMNR 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 query packet for id %u", DNS_PACKET_ID(p)); + + dns_scope_process_query(scope, NULL, p); + } else + log_debug("Invalid LLMNR UDP packet."); + + 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; + + 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) { + r = -errno; + goto fail; + } + + 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); + + scope = manager_find_scope(s->manager, s->read_packet); + if (!scope) { + log_warning("Got LLMNR TCP packet on unknown scope. Ignroing."); + return 0; + } + + if (dns_packet_validate_query(s->read_packet) > 0) { + log_debug("Got query packet for id %u", DNS_PACKET_ID(s->read_packet)); + + dns_scope_process_query(scope, s, s->read_packet); + + /* If no reply packet was set, we free the stream */ + if (s->write_packet) + return 0; + } else + log_debug("Invalid LLMNR TCP packet."); + + dns_stream_free(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; + + 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) { + r = -errno; + goto fail; + } + + 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/resolve/resolved-llmnr.h b/src/resolve/resolved-llmnr.h new file mode 100644 index 0000000000..d489d481e8 --- /dev/null +++ b/src/resolve/resolved-llmnr.h @@ -0,0 +1,34 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +#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/resolve/resolved-manager.c b/src/resolve/resolved-manager.c index dee5e61922..6785a2e3c7 100644 --- a/src/resolve/resolved-manager.c +++ b/src/resolve/resolved-manager.c @@ -38,6 +38,7 @@ #include "resolved-conf.h" #include "resolved-bus.h" #include "resolved-manager.h" +#include "resolved-llmnr.h" #define SEND_TIMEOUT_USEC (200 * USEC_PER_MSEC) @@ -393,66 +394,6 @@ static int manager_watch_hostname(Manager *m) { return 0; } -static 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); -} - -static int manager_llmnr_start(Manager *m) { - int r; - - assert(m); - - if (m->llmnr_support == 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 = SUPPORT_NO; - manager_llmnr_stop(m); - - return 0; -} - int manager_new(Manager **ret) { _cleanup_(manager_freep) Manager *m = NULL; int r; @@ -1316,393 +1257,6 @@ uint32_t manager_find_mtu(Manager *m) { return mtu; } -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; - - 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."); - return 0; - } - - if (dns_packet_validate_reply(p) > 0) { - log_debug("Got 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 query packet for id %u", DNS_PACKET_ID(p)); - - dns_scope_process_query(scope, NULL, p); - } else - log_debug("Invalid LLMNR UDP packet."); - - return 0; -} - -int manager_llmnr_ipv4_udp_fd(Manager *m) { - union sockaddr_union sa = { - .in.sin_family = AF_INET, - .in.sin_port = htobe16(5355), - }; - 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; - - 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(5355), - }; - 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) { - r = -errno; - goto fail; - } - - 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); - - scope = manager_find_scope(s->manager, s->read_packet); - if (!scope) { - log_warning("Got LLMNR TCP packet on unknown scope. Ignroing."); - return 0; - } - - if (dns_packet_validate_query(s->read_packet) > 0) { - log_debug("Got query packet for id %u", DNS_PACKET_ID(s->read_packet)); - - dns_scope_process_query(scope, s, s->read_packet); - - /* If no reply packet was set, we free the stream */ - if (s->write_packet) - return 0; - } else - log_debug("Invalid LLMNR TCP packet."); - - dns_stream_free(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(5355), - }; - 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; - - 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(5355), - }; - 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) { - r = -errno; - goto fail; - } - - return m->llmnr_ipv6_tcp_fd; - -fail: - m->llmnr_ipv6_tcp_fd = safe_close(m->llmnr_ipv6_tcp_fd); - return r; -} - int manager_find_ifindex(Manager *m, int family, const union in_addr_union *in_addr) { LinkAddress *a; diff --git a/src/resolve/resolved-manager.h b/src/resolve/resolved-manager.h index 0f4ffad141..4e70a5b500 100644 --- a/src/resolve/resolved-manager.h +++ b/src/resolve/resolved-manager.h @@ -130,10 +130,6 @@ int manager_recv(Manager *m, int fd, DnsProtocol protocol, DnsPacket **ret); int manager_dns_ipv4_fd(Manager *m); int manager_dns_ipv6_fd(Manager *m); -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); 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); |