-/***
- 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/>.
- ***/
+/* SPDX-License-Identifier: LGPL-2.1+ */
#include <netinet/in.h>
#include <resolv.h>
+#include "errno-util.h"
#include "fd-util.h"
#include "resolved-llmnr.h"
#include "resolved-manager.h"
return 0;
eaddrinuse:
- log_warning("There appears to be another LLMNR responder running. Turning off LLMNR support.");
+ log_warning("Another LLMNR responder prohibits binding the socket to the same port. Turning off LLMNR support.");
m->llmnr_support = RESOLVE_SUPPORT_NO;
manager_llmnr_stop(m);
if (r <= 0)
return r;
+ if (manager_our_packet(m, p))
+ return 0;
+
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) {
+ if (!scope) {
+ log_debug("Got LLMNR UDP packet on unknown scope. Ignoring.");
+ return 0;
+ }
+
+ 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);
.in.sin_family = AF_INET,
.in.sin_port = htobe16(LLMNR_PORT),
};
- static const int one = 1, pmtu = IP_PMTUDISC_DONT, ttl = 255;
+ _cleanup_close_ int s = -1;
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;
+ s = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (s < 0)
+ return log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to create socket: %m");
/* 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_int(s, IPPROTO_IP, IP_TTL, 255);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(UDP): Failed to set IP_TTL: %m");
- r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IP, IP_MULTICAST_TTL, 255);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(UDP): Failed to set IP_MULTICAST_TTL: %m");
- r = setsockopt(m->llmnr_ipv4_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IP, IP_MULTICAST_LOOP, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(UDP): Failed to set IP_MULTICAST_LOOP: %m");
- r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IP, IP_PKTINFO, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(UDP): Failed to set IP_PKTINFO: %m");
- r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IP, IP_RECVTTL, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(UDP): Failed to set IP_RECVTTL: %m");
/* 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 = setsockopt_int(s, IPPROTO_IP, IP_MTU_DISCOVER, IP_PMTUDISC_DONT);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(UDP): Failed to set IP_MTU_DISCOVER: %m");
- r = bind(m->llmnr_ipv4_udp_fd, &sa.sa, sizeof(sa.in));
+ /* first try to bind without SO_REUSEADDR to detect another LLMNR responder */
+ r = bind(s, &sa.sa, sizeof(sa.in));
if (r < 0) {
- r = -errno;
- goto fail;
+ if (errno != EADDRINUSE)
+ return log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to bind socket: %m");
+
+ log_warning("LLMNR-IPv4(UDP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers.");
+
+ /* try again with SO_REUSEADDR */
+ r = setsockopt_int(s, SOL_SOCKET, SO_REUSEADDR, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(UDP): Failed to set SO_REUSEADDR: %m");
+
+ r = bind(s, &sa.sa, sizeof(sa.in));
+ if (r < 0)
+ return log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to bind socket: %m");
+ } else {
+ /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */
+ r = setsockopt_int(s, SOL_SOCKET, SO_REUSEADDR, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(UDP): Failed to set SO_REUSEADDR: %m");
}
- r = sd_event_add_io(m->event, &m->llmnr_ipv4_udp_event_source, m->llmnr_ipv4_udp_fd, EPOLLIN, on_llmnr_packet, m);
+ r = sd_event_add_io(m->event, &m->llmnr_ipv4_udp_event_source, s, EPOLLIN, on_llmnr_packet, m);
if (r < 0)
- goto fail;
+ return log_error_errno(r, "LLMNR-IPv4(UDP): Failed to create event source: %m");
(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;
+ return m->llmnr_ipv4_udp_fd = TAKE_FD(s);
}
int manager_llmnr_ipv6_udp_fd(Manager *m) {
.in6.sin6_family = AF_INET6,
.in6.sin6_port = htobe16(LLMNR_PORT),
};
- static const int one = 1, ttl = 255;
+ _cleanup_close_ int s = -1;
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;
+ s = socket(AF_INET6, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (s < 0)
+ return log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to create socket: %m");
- r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IPV6, IPV6_UNICAST_HOPS, 255);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(UDP): Failed to set IPV6_UNICAST_HOPS: %m");
/* 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_int(s, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, 255);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(UDP): Failed to set IPV6_MULTICAST_HOPS: %m");
- r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(UDP): Failed to set IPV6_MULTICAST_LOOP: %m");
- r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IPV6, IPV6_V6ONLY, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(UDP): Failed to set IPV6_V6ONLY: %m");
- r = setsockopt(m->llmnr_ipv6_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IPV6, IPV6_RECVPKTINFO, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(UDP): Failed to set IPV6_RECVPKTINFO: %m");
- r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(UDP): Failed to set IPV6_RECVHOPLIMIT: %m");
- r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one));
+ /* first try to bind without SO_REUSEADDR to detect another LLMNR responder */
+ r = bind(s, &sa.sa, sizeof(sa.in6));
if (r < 0) {
- r = -errno;
- goto fail;
- }
+ if (errno != EADDRINUSE)
+ return log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to bind socket: %m");
- r = bind(m->llmnr_ipv6_udp_fd, &sa.sa, sizeof(sa.in6));
- if (r < 0) {
- r = -errno;
- goto fail;
+ log_warning("LLMNR-IPv6(UDP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers.");
+
+ /* try again with SO_REUSEADDR */
+ r = setsockopt_int(s, SOL_SOCKET, SO_REUSEADDR, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(UDP): Failed to set SO_REUSEADDR: %m");
+
+ r = bind(s, &sa.sa, sizeof(sa.in6));
+ if (r < 0)
+ return log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to bind socket: %m");
+ } else {
+ /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */
+ r = setsockopt_int(s, SOL_SOCKET, SO_REUSEADDR, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(UDP): Failed to set SO_REUSEADDR: %m");
}
- r = sd_event_add_io(m->event, &m->llmnr_ipv6_udp_event_source, m->llmnr_ipv6_udp_fd, EPOLLIN, on_llmnr_packet, m);
+ r = sd_event_add_io(m->event, &m->llmnr_ipv6_udp_event_source, s, EPOLLIN, on_llmnr_packet, m);
if (r < 0)
- goto fail;
+ return log_error_errno(r, "LLMNR-IPv6(UDP): Failed to create event source: %m");
(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;
+ return m->llmnr_ipv6_udp_fd = TAKE_FD(s);
}
static int on_llmnr_stream_packet(DnsStream *s) {
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
DnsScope *scope;
assert(s);
- assert(s->read_packet);
- scope = manager_find_scope(s->manager, s->read_packet);
+ p = dns_stream_take_read_packet(s);
+ assert(p);
+
+ scope = manager_find_scope(s->manager, p);
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));
+ log_debug("Got LLMNR TCP packet on unknown scope. Ignoring.");
+ else if (dns_packet_validate_query(p) > 0) {
+ log_debug("Got LLMNR TCP query packet for id %u", DNS_PACKET_ID(p));
- dns_scope_process_query(scope, s, s->read_packet);
+ dns_scope_process_query(scope, s, p);
} else
log_debug("Invalid LLMNR TCP packet, ignoring.");
cfd = accept4(fd, NULL, NULL, SOCK_NONBLOCK|SOCK_CLOEXEC);
if (cfd < 0) {
- if (errno == EAGAIN || errno == EINTR)
+ if (ERRNO_IS_ACCEPT_AGAIN(errno))
return 0;
return -errno;
}
- r = dns_stream_new(m, &stream, DNS_PROTOCOL_LLMNR, cfd);
+ r = dns_stream_new(m, &stream, DNS_STREAM_LLMNR_RECV, DNS_PROTOCOL_LLMNR, cfd, NULL);
if (r < 0) {
safe_close(cfd);
return r;
}
stream->on_packet = on_llmnr_stream_packet;
+ /* We don't configure a "complete" handler here, we rely on the default handler than simply drops the
+ * reference to the stream, thus freeing it */
return 0;
}
.in.sin_family = AF_INET,
.in.sin_port = htobe16(LLMNR_PORT),
};
- static const int one = 1, pmtu = IP_PMTUDISC_DONT;
+ _cleanup_close_ int s = -1;
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;
+ s = socket(AF_INET, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (s < 0)
+ return log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to create socket: %m");
/* 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_int(s, IPPROTO_IP, IP_TTL, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(TCP): Failed to set IP_TTL: %m");
- r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IP, IP_PKTINFO, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(TCP): Failed to set IP_PKTINFO: %m");
- r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IP, IP_RECVTTL, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(TCP): Failed to set IP_RECVTTL: %m");
/* 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 = setsockopt_int(s, IPPROTO_IP, IP_MTU_DISCOVER, IP_PMTUDISC_DONT);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(TCP): Failed to set IP_MTU_DISCOVER: %m");
- r = bind(m->llmnr_ipv4_tcp_fd, &sa.sa, sizeof(sa.in));
+ /* first try to bind without SO_REUSEADDR to detect another LLMNR responder */
+ r = bind(s, &sa.sa, sizeof(sa.in));
if (r < 0) {
- r = -errno;
- goto fail;
- }
+ if (errno != EADDRINUSE)
+ return log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to bind socket: %m");
- r = listen(m->llmnr_ipv4_tcp_fd, SOMAXCONN);
- if (r < 0) {
- r = -errno;
- goto fail;
+ log_warning("LLMNR-IPv4(TCP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers.");
+
+ /* try again with SO_REUSEADDR */
+ r = setsockopt_int(s, SOL_SOCKET, SO_REUSEADDR, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(TCP): Failed to set SO_REUSEADDR: %m");
+
+ r = bind(s, &sa.sa, sizeof(sa.in));
+ if (r < 0)
+ return log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to bind socket: %m");
+ } else {
+ /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */
+ r = setsockopt_int(s, SOL_SOCKET, SO_REUSEADDR, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(TCP): Failed to set SO_REUSEADDR: %m");
}
- r = sd_event_add_io(m->event, &m->llmnr_ipv4_tcp_event_source, m->llmnr_ipv4_tcp_fd, EPOLLIN, on_llmnr_stream, m);
+ r = listen(s, SOMAXCONN);
if (r < 0)
- goto fail;
+ return log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to listen the stream: %m");
- (void) sd_event_source_set_description(m->llmnr_ipv4_tcp_event_source, "llmnr-ipv4-tcp");
+ r = sd_event_add_io(m->event, &m->llmnr_ipv4_tcp_event_source, s, EPOLLIN, on_llmnr_stream, m);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv4(TCP): Failed to create event source: %m");
- return m->llmnr_ipv4_tcp_fd;
+ (void) sd_event_source_set_description(m->llmnr_ipv4_tcp_event_source, "llmnr-ipv4-tcp");
-fail:
- m->llmnr_ipv4_tcp_fd = safe_close(m->llmnr_ipv4_tcp_fd);
- return r;
+ return m->llmnr_ipv4_tcp_fd = TAKE_FD(s);
}
int manager_llmnr_ipv6_tcp_fd(Manager *m) {
.in6.sin6_family = AF_INET6,
.in6.sin6_port = htobe16(LLMNR_PORT),
};
- static const int one = 1;
+ _cleanup_close_ int s = -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;
+ s = socket(AF_INET6, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (s < 0)
+ return log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to create socket: %m");
/* 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_int(s, IPPROTO_IPV6, IPV6_UNICAST_HOPS, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(TCP): Failed to set IPV6_UNICAST_HOPS: %m");
- r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IPV6, IPV6_V6ONLY, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(TCP): Failed to set IPV6_V6ONLY: %m");
- r = setsockopt(m->llmnr_ipv6_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IPV6, IPV6_RECVPKTINFO, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(TCP): Failed to set IPV6_RECVPKTINFO: %m");
- r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ r = setsockopt_int(s, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(TCP): Failed to set IPV6_RECVHOPLIMIT: %m");
- r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one));
+ /* first try to bind without SO_REUSEADDR to detect another LLMNR responder */
+ r = bind(s, &sa.sa, sizeof(sa.in6));
if (r < 0) {
- r = -errno;
- goto fail;
- }
+ if (errno != EADDRINUSE)
+ return log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to bind socket: %m");
- r = bind(m->llmnr_ipv6_tcp_fd, &sa.sa, sizeof(sa.in6));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
+ log_warning("LLMNR-IPv6(TCP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers.");
- r = listen(m->llmnr_ipv6_tcp_fd, SOMAXCONN);
- if (r < 0) {
- r = -errno;
- goto fail;
+ /* try again with SO_REUSEADDR */
+ r = setsockopt_int(s, SOL_SOCKET, SO_REUSEADDR, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(TCP): Failed to set SO_REUSEADDR: %m");
+
+ r = bind(s, &sa.sa, sizeof(sa.in6));
+ if (r < 0)
+ return log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to bind socket: %m");
+ } else {
+ /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */
+ r = setsockopt_int(s, SOL_SOCKET, SO_REUSEADDR, true);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(TCP): Failed to set SO_REUSEADDR: %m");
}
- r = sd_event_add_io(m->event, &m->llmnr_ipv6_tcp_event_source, m->llmnr_ipv6_tcp_fd, EPOLLIN, on_llmnr_stream, m);
+ r = listen(s, SOMAXCONN);
if (r < 0)
- goto fail;
+ return log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to listen the stream: %m");
- (void) sd_event_source_set_description(m->llmnr_ipv6_tcp_event_source, "llmnr-ipv6-tcp");
+ r = sd_event_add_io(m->event, &m->llmnr_ipv6_tcp_event_source, s, EPOLLIN, on_llmnr_stream, m);
+ if (r < 0)
+ return log_error_errno(r, "LLMNR-IPv6(TCP): Failed to create event source: %m");
- return m->llmnr_ipv6_tcp_fd;
+ (void) sd_event_source_set_description(m->llmnr_ipv6_tcp_event_source, "llmnr-ipv6-tcp");
-fail:
- m->llmnr_ipv6_tcp_fd = safe_close(m->llmnr_ipv6_tcp_fd);
- return r;
+ return m->llmnr_ipv6_tcp_fd = TAKE_FD(s);
}
projects / thirdparty / systemd.git / blobdiff