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Commit | Line | Data |
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53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
5f402ae8 DM |
2 | /*** |
3 | This file is part of systemd. | |
4 | ||
5 | Copyright 2014 Tom Gundersen <teg@jklm.no> | |
6 | ||
7 | systemd is free software; you can redistribute it and/or modify it | |
8 | under the terms of the GNU Lesser General Public License as published by | |
9 | the Free Software Foundation; either version 2.1 of the License, or | |
10 | (at your option) any later version. | |
11 | ||
12 | systemd is distributed in the hope that it will be useful, but | |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | Lesser General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU Lesser General Public License | |
18 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
19 | ***/ | |
20 | ||
5f402ae8 | 21 | #include <netinet/in.h> |
cf0fbc49 | 22 | #include <resolv.h> |
5f402ae8 | 23 | |
3ffd4af2 | 24 | #include "fd-util.h" |
5f402ae8 | 25 | #include "resolved-llmnr.h" |
3ffd4af2 | 26 | #include "resolved-manager.h" |
5f402ae8 DM |
27 | |
28 | void manager_llmnr_stop(Manager *m) { | |
29 | assert(m); | |
30 | ||
31 | m->llmnr_ipv4_udp_event_source = sd_event_source_unref(m->llmnr_ipv4_udp_event_source); | |
32 | m->llmnr_ipv4_udp_fd = safe_close(m->llmnr_ipv4_udp_fd); | |
33 | ||
34 | m->llmnr_ipv6_udp_event_source = sd_event_source_unref(m->llmnr_ipv6_udp_event_source); | |
35 | m->llmnr_ipv6_udp_fd = safe_close(m->llmnr_ipv6_udp_fd); | |
36 | ||
37 | m->llmnr_ipv4_tcp_event_source = sd_event_source_unref(m->llmnr_ipv4_tcp_event_source); | |
38 | m->llmnr_ipv4_tcp_fd = safe_close(m->llmnr_ipv4_tcp_fd); | |
39 | ||
40 | m->llmnr_ipv6_tcp_event_source = sd_event_source_unref(m->llmnr_ipv6_tcp_event_source); | |
41 | m->llmnr_ipv6_tcp_fd = safe_close(m->llmnr_ipv6_tcp_fd); | |
42 | } | |
43 | ||
44 | int manager_llmnr_start(Manager *m) { | |
45 | int r; | |
46 | ||
47 | assert(m); | |
48 | ||
af49ca27 | 49 | if (m->llmnr_support == RESOLVE_SUPPORT_NO) |
5f402ae8 DM |
50 | return 0; |
51 | ||
52 | r = manager_llmnr_ipv4_udp_fd(m); | |
53 | if (r == -EADDRINUSE) | |
54 | goto eaddrinuse; | |
55 | if (r < 0) | |
56 | return r; | |
57 | ||
58 | r = manager_llmnr_ipv4_tcp_fd(m); | |
59 | if (r == -EADDRINUSE) | |
60 | goto eaddrinuse; | |
61 | if (r < 0) | |
62 | return r; | |
63 | ||
64 | if (socket_ipv6_is_supported()) { | |
65 | r = manager_llmnr_ipv6_udp_fd(m); | |
66 | if (r == -EADDRINUSE) | |
67 | goto eaddrinuse; | |
68 | if (r < 0) | |
69 | return r; | |
70 | ||
71 | r = manager_llmnr_ipv6_tcp_fd(m); | |
72 | if (r == -EADDRINUSE) | |
73 | goto eaddrinuse; | |
74 | if (r < 0) | |
75 | return r; | |
76 | } | |
77 | ||
78 | return 0; | |
79 | ||
80 | eaddrinuse: | |
007ef0a2 | 81 | log_warning("Another LLMNR responder prohibits binding the socket to the same port. Turning off LLMNR support."); |
af49ca27 | 82 | m->llmnr_support = RESOLVE_SUPPORT_NO; |
5f402ae8 DM |
83 | manager_llmnr_stop(m); |
84 | ||
85 | return 0; | |
86 | } | |
87 | ||
88 | static int on_llmnr_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) { | |
89 | _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; | |
90 | DnsTransaction *t = NULL; | |
91 | Manager *m = userdata; | |
92 | DnsScope *scope; | |
93 | int r; | |
94 | ||
b30bf55d LP |
95 | assert(s); |
96 | assert(fd >= 0); | |
97 | assert(m); | |
98 | ||
5f402ae8 DM |
99 | r = manager_recv(m, fd, DNS_PROTOCOL_LLMNR, &p); |
100 | if (r <= 0) | |
101 | return r; | |
102 | ||
103 | scope = manager_find_scope(m, p); | |
b30bf55d | 104 | if (!scope) |
5f402ae8 | 105 | log_warning("Got LLMNR UDP packet on unknown scope. Ignoring."); |
b30bf55d LP |
106 | else if (dns_packet_validate_reply(p) > 0) { |
107 | log_debug("Got LLMNR UDP reply packet for id %u", DNS_PACKET_ID(p)); | |
5f402ae8 DM |
108 | |
109 | dns_scope_check_conflicts(scope, p); | |
110 | ||
111 | t = hashmap_get(m->dns_transactions, UINT_TO_PTR(DNS_PACKET_ID(p))); | |
112 | if (t) | |
113 | dns_transaction_process_reply(t, p); | |
114 | ||
115 | } else if (dns_packet_validate_query(p) > 0) { | |
b30bf55d | 116 | log_debug("Got LLMNR UDP query packet for id %u", DNS_PACKET_ID(p)); |
5f402ae8 DM |
117 | |
118 | dns_scope_process_query(scope, NULL, p); | |
119 | } else | |
2c6bf498 | 120 | log_debug("Invalid LLMNR UDP packet, ignoring."); |
5f402ae8 DM |
121 | |
122 | return 0; | |
123 | } | |
124 | ||
125 | int manager_llmnr_ipv4_udp_fd(Manager *m) { | |
126 | union sockaddr_union sa = { | |
127 | .in.sin_family = AF_INET, | |
22a37591 | 128 | .in.sin_port = htobe16(LLMNR_PORT), |
5f402ae8 DM |
129 | }; |
130 | static const int one = 1, pmtu = IP_PMTUDISC_DONT, ttl = 255; | |
131 | int r; | |
132 | ||
133 | assert(m); | |
134 | ||
135 | if (m->llmnr_ipv4_udp_fd >= 0) | |
136 | return m->llmnr_ipv4_udp_fd; | |
137 | ||
138 | m->llmnr_ipv4_udp_fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); | |
139 | if (m->llmnr_ipv4_udp_fd < 0) | |
007ef0a2 | 140 | return log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to create socket: %m"); |
5f402ae8 DM |
141 | |
142 | /* RFC 4795, section 2.5 recommends setting the TTL of UDP packets to 255. */ | |
143 | r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl)); | |
144 | if (r < 0) { | |
007ef0a2 | 145 | r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set IP_TTL: %m"); |
5f402ae8 DM |
146 | goto fail; |
147 | } | |
148 | ||
149 | r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)); | |
150 | if (r < 0) { | |
007ef0a2 | 151 | r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set IP_MULTICAST_TTL: %m"); |
5f402ae8 DM |
152 | goto fail; |
153 | } | |
154 | ||
155 | r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one, sizeof(one)); | |
156 | if (r < 0) { | |
007ef0a2 | 157 | r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set IP_MULTICAST_LOOP: %m"); |
5f402ae8 DM |
158 | goto fail; |
159 | } | |
160 | ||
161 | r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one)); | |
162 | if (r < 0) { | |
007ef0a2 | 163 | r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set IP_PKTINFO: %m"); |
5f402ae8 DM |
164 | goto fail; |
165 | } | |
166 | ||
167 | r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one)); | |
168 | if (r < 0) { | |
007ef0a2 | 169 | r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set IP_RECVTTL: %m"); |
5f402ae8 DM |
170 | goto fail; |
171 | } | |
172 | ||
173 | /* Disable Don't-Fragment bit in the IP header */ | |
174 | r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MTU_DISCOVER, &pmtu, sizeof(pmtu)); | |
175 | if (r < 0) { | |
007ef0a2 | 176 | r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set IP_MTU_DISCOVER: %m"); |
5f402ae8 DM |
177 | goto fail; |
178 | } | |
179 | ||
007ef0a2 | 180 | /* first try to bind without SO_REUSEADDR to detect another LLMNR responder */ |
5f402ae8 DM |
181 | r = bind(m->llmnr_ipv4_udp_fd, &sa.sa, sizeof(sa.in)); |
182 | if (r < 0) { | |
007ef0a2 YW |
183 | if (errno != EADDRINUSE) { |
184 | r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to bind socket: %m"); | |
185 | goto fail; | |
186 | } | |
187 | ||
188 | log_warning("LLMNR-IPv4(UDP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers."); | |
189 | ||
190 | /* try again with SO_REUSEADDR */ | |
191 | r = setsockopt(m->llmnr_ipv4_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); | |
192 | if (r < 0) { | |
193 | r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set SO_REUSEADDR: %m"); | |
194 | goto fail; | |
195 | } | |
196 | ||
197 | r = bind(m->llmnr_ipv4_udp_fd, &sa.sa, sizeof(sa.in)); | |
198 | if (r < 0) { | |
199 | r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to bind socket: %m"); | |
200 | goto fail; | |
201 | } | |
202 | } else { | |
203 | /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */ | |
204 | r = setsockopt(m->llmnr_ipv4_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); | |
205 | if (r < 0) { | |
206 | r = log_error_errno(errno, "LLMNR-IPv4(UDP): Failed to set SO_REUSEADDR: %m"); | |
207 | goto fail; | |
208 | } | |
5f402ae8 DM |
209 | } |
210 | ||
211 | r = sd_event_add_io(m->event, &m->llmnr_ipv4_udp_event_source, m->llmnr_ipv4_udp_fd, EPOLLIN, on_llmnr_packet, m); | |
212 | if (r < 0) | |
213 | goto fail; | |
214 | ||
aa4a9deb LP |
215 | (void) sd_event_source_set_description(m->llmnr_ipv4_udp_event_source, "llmnr-ipv4-udp"); |
216 | ||
5f402ae8 DM |
217 | return m->llmnr_ipv4_udp_fd; |
218 | ||
219 | fail: | |
220 | m->llmnr_ipv4_udp_fd = safe_close(m->llmnr_ipv4_udp_fd); | |
221 | return r; | |
222 | } | |
223 | ||
224 | int manager_llmnr_ipv6_udp_fd(Manager *m) { | |
225 | union sockaddr_union sa = { | |
226 | .in6.sin6_family = AF_INET6, | |
22a37591 | 227 | .in6.sin6_port = htobe16(LLMNR_PORT), |
5f402ae8 DM |
228 | }; |
229 | static const int one = 1, ttl = 255; | |
230 | int r; | |
231 | ||
232 | assert(m); | |
233 | ||
234 | if (m->llmnr_ipv6_udp_fd >= 0) | |
235 | return m->llmnr_ipv6_udp_fd; | |
236 | ||
237 | m->llmnr_ipv6_udp_fd = socket(AF_INET6, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); | |
238 | if (m->llmnr_ipv6_udp_fd < 0) | |
007ef0a2 | 239 | return log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to create socket: %m"); |
5f402ae8 DM |
240 | |
241 | r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl)); | |
242 | if (r < 0) { | |
007ef0a2 | 243 | r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set IPV6_UNICAST_HOPS: %m"); |
5f402ae8 DM |
244 | goto fail; |
245 | } | |
246 | ||
247 | /* RFC 4795, section 2.5 recommends setting the TTL of UDP packets to 255. */ | |
248 | r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)); | |
249 | if (r < 0) { | |
007ef0a2 | 250 | r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set IPV6_MULTICAST_HOPS: %m"); |
5f402ae8 DM |
251 | goto fail; |
252 | } | |
253 | ||
254 | r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &one, sizeof(one)); | |
255 | if (r < 0) { | |
007ef0a2 | 256 | r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set IPV6_MULTICAST_LOOP: %m"); |
5f402ae8 DM |
257 | goto fail; |
258 | } | |
259 | ||
260 | r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one)); | |
261 | if (r < 0) { | |
007ef0a2 | 262 | r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set IPV6_V6ONLY: %m"); |
5f402ae8 DM |
263 | goto fail; |
264 | } | |
265 | ||
266 | r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one)); | |
267 | if (r < 0) { | |
007ef0a2 | 268 | r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set IPV6_RECVPKTINFO: %m"); |
5f402ae8 DM |
269 | goto fail; |
270 | } | |
271 | ||
272 | r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one)); | |
273 | if (r < 0) { | |
007ef0a2 | 274 | r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set IPV6_RECVHOPLIMIT: %m"); |
5f402ae8 DM |
275 | goto fail; |
276 | } | |
277 | ||
007ef0a2 | 278 | /* first try to bind without SO_REUSEADDR to detect another LLMNR responder */ |
5f402ae8 DM |
279 | r = bind(m->llmnr_ipv6_udp_fd, &sa.sa, sizeof(sa.in6)); |
280 | if (r < 0) { | |
007ef0a2 YW |
281 | if (errno != EADDRINUSE) { |
282 | r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to bind socket: %m"); | |
283 | goto fail; | |
284 | } | |
285 | ||
286 | log_warning("LLMNR-IPv6(UDP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers."); | |
287 | ||
288 | /* try again with SO_REUSEADDR */ | |
289 | r = setsockopt(m->llmnr_ipv6_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); | |
290 | if (r < 0) { | |
291 | r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set SO_REUSEADDR: %m"); | |
292 | goto fail; | |
293 | } | |
294 | ||
295 | r = bind(m->llmnr_ipv6_udp_fd, &sa.sa, sizeof(sa.in6)); | |
296 | if (r < 0) { | |
297 | r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to bind socket: %m"); | |
298 | goto fail; | |
299 | } | |
300 | } else { | |
301 | /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */ | |
302 | r = setsockopt(m->llmnr_ipv6_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); | |
303 | if (r < 0) { | |
304 | r = log_error_errno(errno, "LLMNR-IPv6(UDP): Failed to set SO_REUSEADDR: %m"); | |
305 | goto fail; | |
306 | } | |
5f402ae8 DM |
307 | } |
308 | ||
309 | r = sd_event_add_io(m->event, &m->llmnr_ipv6_udp_event_source, m->llmnr_ipv6_udp_fd, EPOLLIN, on_llmnr_packet, m); | |
35908b98 | 310 | if (r < 0) |
5f402ae8 | 311 | goto fail; |
5f402ae8 | 312 | |
aa4a9deb LP |
313 | (void) sd_event_source_set_description(m->llmnr_ipv6_udp_event_source, "llmnr-ipv6-udp"); |
314 | ||
5f402ae8 DM |
315 | return m->llmnr_ipv6_udp_fd; |
316 | ||
317 | fail: | |
318 | m->llmnr_ipv6_udp_fd = safe_close(m->llmnr_ipv6_udp_fd); | |
319 | return r; | |
320 | } | |
321 | ||
322 | static int on_llmnr_stream_packet(DnsStream *s) { | |
323 | DnsScope *scope; | |
324 | ||
325 | assert(s); | |
b30bf55d | 326 | assert(s->read_packet); |
5f402ae8 DM |
327 | |
328 | scope = manager_find_scope(s->manager, s->read_packet); | |
b30bf55d | 329 | if (!scope) |
0ea929d5 | 330 | log_warning("Got LLMNR TCP packet on unknown scope. Ignoring."); |
b30bf55d LP |
331 | else if (dns_packet_validate_query(s->read_packet) > 0) { |
332 | log_debug("Got LLMNR TCP query packet for id %u", DNS_PACKET_ID(s->read_packet)); | |
5f402ae8 DM |
333 | |
334 | dns_scope_process_query(scope, s, s->read_packet); | |
5f402ae8 | 335 | } else |
b30bf55d | 336 | log_debug("Invalid LLMNR TCP packet, ignoring."); |
5f402ae8 | 337 | |
b30bf55d | 338 | dns_stream_unref(s); |
5f402ae8 DM |
339 | return 0; |
340 | } | |
341 | ||
342 | static int on_llmnr_stream(sd_event_source *s, int fd, uint32_t revents, void *userdata) { | |
343 | DnsStream *stream; | |
344 | Manager *m = userdata; | |
345 | int cfd, r; | |
346 | ||
347 | cfd = accept4(fd, NULL, NULL, SOCK_NONBLOCK|SOCK_CLOEXEC); | |
348 | if (cfd < 0) { | |
3742095b | 349 | if (IN_SET(errno, EAGAIN, EINTR)) |
5f402ae8 DM |
350 | return 0; |
351 | ||
352 | return -errno; | |
353 | } | |
354 | ||
355 | r = dns_stream_new(m, &stream, DNS_PROTOCOL_LLMNR, cfd); | |
356 | if (r < 0) { | |
357 | safe_close(cfd); | |
358 | return r; | |
359 | } | |
360 | ||
361 | stream->on_packet = on_llmnr_stream_packet; | |
362 | return 0; | |
363 | } | |
364 | ||
365 | int manager_llmnr_ipv4_tcp_fd(Manager *m) { | |
366 | union sockaddr_union sa = { | |
367 | .in.sin_family = AF_INET, | |
22a37591 | 368 | .in.sin_port = htobe16(LLMNR_PORT), |
5f402ae8 DM |
369 | }; |
370 | static const int one = 1, pmtu = IP_PMTUDISC_DONT; | |
371 | int r; | |
372 | ||
373 | assert(m); | |
374 | ||
375 | if (m->llmnr_ipv4_tcp_fd >= 0) | |
376 | return m->llmnr_ipv4_tcp_fd; | |
377 | ||
378 | m->llmnr_ipv4_tcp_fd = socket(AF_INET, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); | |
379 | if (m->llmnr_ipv4_tcp_fd < 0) | |
007ef0a2 | 380 | return log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to create socket: %m"); |
5f402ae8 DM |
381 | |
382 | /* RFC 4795, section 2.5. requires setting the TTL of TCP streams to 1 */ | |
383 | r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_TTL, &one, sizeof(one)); | |
384 | if (r < 0) { | |
007ef0a2 | 385 | r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to set IP_TTL: %m"); |
5f402ae8 DM |
386 | goto fail; |
387 | } | |
388 | ||
389 | r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one)); | |
390 | if (r < 0) { | |
007ef0a2 | 391 | r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to set IP_PKTINFO: %m"); |
5f402ae8 DM |
392 | goto fail; |
393 | } | |
394 | ||
395 | r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one)); | |
396 | if (r < 0) { | |
007ef0a2 | 397 | r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to set IP_RECVTTL: %m"); |
5f402ae8 DM |
398 | goto fail; |
399 | } | |
400 | ||
401 | /* Disable Don't-Fragment bit in the IP header */ | |
402 | r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_MTU_DISCOVER, &pmtu, sizeof(pmtu)); | |
403 | if (r < 0) { | |
007ef0a2 | 404 | r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to set IP_MTU_DISCOVER: %m"); |
5f402ae8 DM |
405 | goto fail; |
406 | } | |
407 | ||
007ef0a2 | 408 | /* first try to bind without SO_REUSEADDR to detect another LLMNR responder */ |
5f402ae8 DM |
409 | r = bind(m->llmnr_ipv4_tcp_fd, &sa.sa, sizeof(sa.in)); |
410 | if (r < 0) { | |
007ef0a2 YW |
411 | if (errno != EADDRINUSE) { |
412 | r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to bind socket: %m"); | |
413 | goto fail; | |
414 | } | |
415 | ||
416 | log_warning("LLMNR-IPv4(TCP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers."); | |
417 | ||
418 | /* try again with SO_REUSEADDR */ | |
419 | r = setsockopt(m->llmnr_ipv4_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); | |
420 | if (r < 0) { | |
421 | r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to set SO_REUSEADDR: %m"); | |
422 | goto fail; | |
423 | } | |
424 | ||
425 | r = bind(m->llmnr_ipv4_tcp_fd, &sa.sa, sizeof(sa.in)); | |
426 | if (r < 0) { | |
427 | r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to bind socket: %m"); | |
428 | goto fail; | |
429 | } | |
430 | } else { | |
431 | /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */ | |
432 | r = setsockopt(m->llmnr_ipv4_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); | |
433 | if (r < 0) { | |
434 | r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to set SO_REUSEADDR: %m"); | |
435 | goto fail; | |
436 | } | |
5f402ae8 DM |
437 | } |
438 | ||
439 | r = listen(m->llmnr_ipv4_tcp_fd, SOMAXCONN); | |
440 | if (r < 0) { | |
007ef0a2 | 441 | r = log_error_errno(errno, "LLMNR-IPv4(TCP): Failed to listen the stream: %m"); |
5f402ae8 DM |
442 | goto fail; |
443 | } | |
444 | ||
445 | r = sd_event_add_io(m->event, &m->llmnr_ipv4_tcp_event_source, m->llmnr_ipv4_tcp_fd, EPOLLIN, on_llmnr_stream, m); | |
446 | if (r < 0) | |
447 | goto fail; | |
448 | ||
aa4a9deb LP |
449 | (void) sd_event_source_set_description(m->llmnr_ipv4_tcp_event_source, "llmnr-ipv4-tcp"); |
450 | ||
5f402ae8 DM |
451 | return m->llmnr_ipv4_tcp_fd; |
452 | ||
453 | fail: | |
454 | m->llmnr_ipv4_tcp_fd = safe_close(m->llmnr_ipv4_tcp_fd); | |
455 | return r; | |
456 | } | |
457 | ||
458 | int manager_llmnr_ipv6_tcp_fd(Manager *m) { | |
459 | union sockaddr_union sa = { | |
460 | .in6.sin6_family = AF_INET6, | |
22a37591 | 461 | .in6.sin6_port = htobe16(LLMNR_PORT), |
5f402ae8 DM |
462 | }; |
463 | static const int one = 1; | |
464 | int r; | |
465 | ||
466 | assert(m); | |
467 | ||
468 | if (m->llmnr_ipv6_tcp_fd >= 0) | |
469 | return m->llmnr_ipv6_tcp_fd; | |
470 | ||
471 | m->llmnr_ipv6_tcp_fd = socket(AF_INET6, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); | |
472 | if (m->llmnr_ipv6_tcp_fd < 0) | |
007ef0a2 | 473 | return log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to create socket: %m"); |
5f402ae8 DM |
474 | |
475 | /* RFC 4795, section 2.5. requires setting the TTL of TCP streams to 1 */ | |
476 | r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &one, sizeof(one)); | |
477 | if (r < 0) { | |
007ef0a2 | 478 | r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set IPV6_UNICAST_HOPS: %m"); |
5f402ae8 DM |
479 | goto fail; |
480 | } | |
481 | ||
482 | r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one)); | |
483 | if (r < 0) { | |
007ef0a2 | 484 | r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set IPV6_V6ONLY: %m"); |
5f402ae8 DM |
485 | goto fail; |
486 | } | |
487 | ||
488 | r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one)); | |
489 | if (r < 0) { | |
007ef0a2 | 490 | r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set IPV6_RECVPKTINFO: %m"); |
5f402ae8 DM |
491 | goto fail; |
492 | } | |
493 | ||
494 | r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one)); | |
495 | if (r < 0) { | |
007ef0a2 | 496 | r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set IPV6_RECVHOPLIMIT: %m"); |
5f402ae8 DM |
497 | goto fail; |
498 | } | |
499 | ||
007ef0a2 | 500 | /* first try to bind without SO_REUSEADDR to detect another LLMNR responder */ |
5f402ae8 DM |
501 | r = bind(m->llmnr_ipv6_tcp_fd, &sa.sa, sizeof(sa.in6)); |
502 | if (r < 0) { | |
007ef0a2 YW |
503 | if (errno != EADDRINUSE) { |
504 | r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to bind socket: %m"); | |
505 | goto fail; | |
506 | } | |
507 | ||
508 | log_warning("LLMNR-IPv6(TCP): There appears to be another LLMNR responder running, or previously systemd-resolved crashed with some outstanding transfers."); | |
509 | ||
510 | /* try again with SO_REUSEADDR */ | |
511 | r = setsockopt(m->llmnr_ipv6_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); | |
512 | if (r < 0) { | |
513 | r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set SO_REUSEADDR: %m"); | |
514 | goto fail; | |
515 | } | |
516 | ||
517 | r = bind(m->llmnr_ipv6_tcp_fd, &sa.sa, sizeof(sa.in6)); | |
518 | if (r < 0) { | |
519 | r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to bind socket: %m"); | |
520 | goto fail; | |
521 | } | |
522 | } else { | |
523 | /* enable SO_REUSEADDR for the case that the user really wants multiple LLMNR responders */ | |
524 | r = setsockopt(m->llmnr_ipv6_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); | |
525 | if (r < 0) { | |
526 | r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to set SO_REUSEADDR: %m"); | |
527 | goto fail; | |
528 | } | |
5f402ae8 DM |
529 | } |
530 | ||
531 | r = listen(m->llmnr_ipv6_tcp_fd, SOMAXCONN); | |
532 | if (r < 0) { | |
007ef0a2 | 533 | r = log_error_errno(errno, "LLMNR-IPv6(TCP): Failed to listen the stream: %m"); |
5f402ae8 DM |
534 | goto fail; |
535 | } | |
536 | ||
537 | r = sd_event_add_io(m->event, &m->llmnr_ipv6_tcp_event_source, m->llmnr_ipv6_tcp_fd, EPOLLIN, on_llmnr_stream, m); | |
ee8d9305 | 538 | if (r < 0) |
5f402ae8 | 539 | goto fail; |
5f402ae8 | 540 | |
aa4a9deb LP |
541 | (void) sd_event_source_set_description(m->llmnr_ipv6_tcp_event_source, "llmnr-ipv6-tcp"); |
542 | ||
5f402ae8 DM |
543 | return m->llmnr_ipv6_tcp_fd; |
544 | ||
545 | fail: | |
546 | m->llmnr_ipv6_tcp_fd = safe_close(m->llmnr_ipv6_tcp_fd); | |
547 | return r; | |
548 | } |