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Diffstat (limited to 'src/resolve/resolved-mdns.c')
-rw-r--r--src/resolve/resolved-mdns.c287
1 files changed, 0 insertions, 287 deletions
diff --git a/src/resolve/resolved-mdns.c b/src/resolve/resolved-mdns.c
deleted file mode 100644
index b13b1d0144..0000000000
--- a/src/resolve/resolved-mdns.c
+++ /dev/null
@@ -1,287 +0,0 @@
-/***
- 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 <resolv.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-
-#include "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;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-01 11:24:52 +0000