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resolve: rename Link.name -> Link.ifname
[thirdparty/systemd.git] / src / resolve / resolved-manager.c
1 /* SPDX-License-Identifier: LGPL-2.1+ */
2
3 #include <fcntl.h>
4 #include <netinet/in.h>
5 #include <poll.h>
6 #include <sys/ioctl.h>
7 #include <sys/stat.h>
8 #include <sys/types.h>
9 #include <unistd.h>
10
11 #if HAVE_LIBIDN2
12 #include <idn2.h>
13 #endif
14
15 #include "af-list.h"
16 #include "alloc-util.h"
17 #include "dirent-util.h"
18 #include "dns-domain.h"
19 #include "fd-util.h"
20 #include "fileio.h"
21 #include "hostname-util.h"
22 #include "io-util.h"
23 #include "missing_network.h"
24 #include "netlink-util.h"
25 #include "network-internal.h"
26 #include "ordered-set.h"
27 #include "parse-util.h"
28 #include "random-util.h"
29 #include "resolved-bus.h"
30 #include "resolved-conf.h"
31 #include "resolved-dns-stub.h"
32 #include "resolved-dnssd.h"
33 #include "resolved-etc-hosts.h"
34 #include "resolved-llmnr.h"
35 #include "resolved-manager.h"
36 #include "resolved-mdns.h"
37 #include "resolved-resolv-conf.h"
38 #include "socket-util.h"
39 #include "string-table.h"
40 #include "string-util.h"
41 #include "utf8.h"
42
43 #define SEND_TIMEOUT_USEC (200 * USEC_PER_MSEC)
44
45 static int manager_process_link(sd_netlink *rtnl, sd_netlink_message *mm, void *userdata) {
46 Manager *m = userdata;
47 uint16_t type;
48 Link *l;
49 int ifindex, r;
50
51 assert(rtnl);
52 assert(m);
53 assert(mm);
54
55 r = sd_netlink_message_get_type(mm, &type);
56 if (r < 0)
57 goto fail;
58
59 r = sd_rtnl_message_link_get_ifindex(mm, &ifindex);
60 if (r < 0)
61 goto fail;
62
63 l = hashmap_get(m->links, INT_TO_PTR(ifindex));
64
65 switch (type) {
66
67 case RTM_NEWLINK:{
68 bool is_new = !l;
69
70 if (!l) {
71 r = link_new(m, &l, ifindex);
72 if (r < 0)
73 goto fail;
74 }
75
76 r = link_process_rtnl(l, mm);
77 if (r < 0)
78 goto fail;
79
80 r = link_update(l);
81 if (r < 0)
82 goto fail;
83
84 if (is_new)
85 log_debug("Found new link %i/%s", ifindex, l->ifname);
86
87 break;
88 }
89
90 case RTM_DELLINK:
91 if (l) {
92 log_debug("Removing link %i/%s", l->ifindex, l->ifname);
93 link_remove_user(l);
94 link_free(l);
95 }
96
97 break;
98 }
99
100 return 0;
101
102 fail:
103 log_warning_errno(r, "Failed to process RTNL link message: %m");
104 return 0;
105 }
106
107 static int manager_process_address(sd_netlink *rtnl, sd_netlink_message *mm, void *userdata) {
108 Manager *m = userdata;
109 union in_addr_union address;
110 uint16_t type;
111 int r, ifindex, family;
112 LinkAddress *a;
113 Link *l;
114
115 assert(rtnl);
116 assert(mm);
117 assert(m);
118
119 r = sd_netlink_message_get_type(mm, &type);
120 if (r < 0)
121 goto fail;
122
123 r = sd_rtnl_message_addr_get_ifindex(mm, &ifindex);
124 if (r < 0)
125 goto fail;
126
127 l = hashmap_get(m->links, INT_TO_PTR(ifindex));
128 if (!l)
129 return 0;
130
131 r = sd_rtnl_message_addr_get_family(mm, &family);
132 if (r < 0)
133 goto fail;
134
135 switch (family) {
136
137 case AF_INET:
138 r = sd_netlink_message_read_in_addr(mm, IFA_LOCAL, &address.in);
139 if (r < 0) {
140 r = sd_netlink_message_read_in_addr(mm, IFA_ADDRESS, &address.in);
141 if (r < 0)
142 goto fail;
143 }
144
145 break;
146
147 case AF_INET6:
148 r = sd_netlink_message_read_in6_addr(mm, IFA_LOCAL, &address.in6);
149 if (r < 0) {
150 r = sd_netlink_message_read_in6_addr(mm, IFA_ADDRESS, &address.in6);
151 if (r < 0)
152 goto fail;
153 }
154
155 break;
156
157 default:
158 return 0;
159 }
160
161 a = link_find_address(l, family, &address);
162
163 switch (type) {
164
165 case RTM_NEWADDR:
166
167 if (!a) {
168 r = link_address_new(l, &a, family, &address);
169 if (r < 0)
170 return r;
171 }
172
173 r = link_address_update_rtnl(a, mm);
174 if (r < 0)
175 return r;
176
177 break;
178
179 case RTM_DELADDR:
180 link_address_free(a);
181 break;
182 }
183
184 return 0;
185
186 fail:
187 log_warning_errno(r, "Failed to process RTNL address message: %m");
188 return 0;
189 }
190
191 static int manager_rtnl_listen(Manager *m) {
192 _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
193 sd_netlink_message *i;
194 int r;
195
196 assert(m);
197
198 /* First, subscribe to interfaces coming and going */
199 r = sd_netlink_open(&m->rtnl);
200 if (r < 0)
201 return r;
202
203 r = sd_netlink_attach_event(m->rtnl, m->event, SD_EVENT_PRIORITY_IMPORTANT);
204 if (r < 0)
205 return r;
206
207 r = sd_netlink_add_match(m->rtnl, NULL, RTM_NEWLINK, manager_process_link, NULL, m, "resolve-NEWLINK");
208 if (r < 0)
209 return r;
210
211 r = sd_netlink_add_match(m->rtnl, NULL, RTM_DELLINK, manager_process_link, NULL, m, "resolve-DELLINK");
212 if (r < 0)
213 return r;
214
215 r = sd_netlink_add_match(m->rtnl, NULL, RTM_NEWADDR, manager_process_address, NULL, m, "resolve-NEWADDR");
216 if (r < 0)
217 return r;
218
219 r = sd_netlink_add_match(m->rtnl, NULL, RTM_DELADDR, manager_process_address, NULL, m, "resolve-DELADDR");
220 if (r < 0)
221 return r;
222
223 /* Then, enumerate all links */
224 r = sd_rtnl_message_new_link(m->rtnl, &req, RTM_GETLINK, 0);
225 if (r < 0)
226 return r;
227
228 r = sd_netlink_message_request_dump(req, true);
229 if (r < 0)
230 return r;
231
232 r = sd_netlink_call(m->rtnl, req, 0, &reply);
233 if (r < 0)
234 return r;
235
236 for (i = reply; i; i = sd_netlink_message_next(i)) {
237 r = manager_process_link(m->rtnl, i, m);
238 if (r < 0)
239 return r;
240 }
241
242 req = sd_netlink_message_unref(req);
243 reply = sd_netlink_message_unref(reply);
244
245 /* Finally, enumerate all addresses, too */
246 r = sd_rtnl_message_new_addr(m->rtnl, &req, RTM_GETADDR, 0, AF_UNSPEC);
247 if (r < 0)
248 return r;
249
250 r = sd_netlink_message_request_dump(req, true);
251 if (r < 0)
252 return r;
253
254 r = sd_netlink_call(m->rtnl, req, 0, &reply);
255 if (r < 0)
256 return r;
257
258 for (i = reply; i; i = sd_netlink_message_next(i)) {
259 r = manager_process_address(m->rtnl, i, m);
260 if (r < 0)
261 return r;
262 }
263
264 return r;
265 }
266
267 static int on_network_event(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
268 Manager *m = userdata;
269 Iterator i;
270 Link *l;
271 int r;
272
273 assert(m);
274
275 sd_network_monitor_flush(m->network_monitor);
276
277 HASHMAP_FOREACH(l, m->links, i) {
278 r = link_update(l);
279 if (r < 0)
280 log_warning_errno(r, "Failed to update monitor information for %i: %m", l->ifindex);
281 }
282
283 (void) manager_write_resolv_conf(m);
284
285 return 0;
286 }
287
288 static int manager_network_monitor_listen(Manager *m) {
289 int r, fd, events;
290
291 assert(m);
292
293 r = sd_network_monitor_new(&m->network_monitor, NULL);
294 if (r < 0)
295 return r;
296
297 fd = sd_network_monitor_get_fd(m->network_monitor);
298 if (fd < 0)
299 return fd;
300
301 events = sd_network_monitor_get_events(m->network_monitor);
302 if (events < 0)
303 return events;
304
305 r = sd_event_add_io(m->event, &m->network_event_source, fd, events, &on_network_event, m);
306 if (r < 0)
307 return r;
308
309 r = sd_event_source_set_priority(m->network_event_source, SD_EVENT_PRIORITY_IMPORTANT+5);
310 if (r < 0)
311 return r;
312
313 (void) sd_event_source_set_description(m->network_event_source, "network-monitor");
314
315 return 0;
316 }
317
318 static int determine_hostname(char **full_hostname, char **llmnr_hostname, char **mdns_hostname) {
319 _cleanup_free_ char *h = NULL, *n = NULL;
320 #if HAVE_LIBIDN2
321 _cleanup_free_ char *utf8 = NULL;
322 #elif HAVE_LIBIDN
323 int k;
324 #endif
325 char label[DNS_LABEL_MAX];
326 const char *p, *decoded;
327 int r;
328
329 assert(full_hostname);
330 assert(llmnr_hostname);
331 assert(mdns_hostname);
332
333 /* Extract and normalize the first label of the locally configured hostname, and check it's not "localhost". */
334
335 r = gethostname_strict(&h);
336 if (r < 0)
337 return log_debug_errno(r, "Can't determine system hostname: %m");
338
339 p = h;
340 r = dns_label_unescape(&p, label, sizeof label, 0);
341 if (r < 0)
342 return log_error_errno(r, "Failed to unescape host name: %m");
343 if (r == 0)
344 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
345 "Couldn't find a single label in hostname.");
346
347 #if HAVE_LIBIDN2
348 r = idn2_to_unicode_8z8z(label, &utf8, 0);
349 if (r != IDN2_OK)
350 return log_error("Failed to undo IDNA: %s", idn2_strerror(r));
351 assert(utf8_is_valid(utf8));
352
353 r = strlen(utf8);
354 decoded = utf8;
355 #elif HAVE_LIBIDN
356 k = dns_label_undo_idna(label, r, label, sizeof label);
357 if (k < 0)
358 return log_error_errno(k, "Failed to undo IDNA: %m");
359 if (k > 0)
360 r = k;
361
362 if (!utf8_is_valid(label))
363 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
364 "System hostname is not UTF-8 clean.");
365 decoded = label;
366 #else
367 decoded = label; /* no decoding */
368 #endif
369
370 r = dns_label_escape_new(decoded, r, &n);
371 if (r < 0)
372 return log_error_errno(r, "Failed to escape host name: %m");
373
374 if (is_localhost(n))
375 return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
376 "System hostname is 'localhost', ignoring.");
377
378 r = dns_name_concat(n, "local", 0, mdns_hostname);
379 if (r < 0)
380 return log_error_errno(r, "Failed to determine mDNS hostname: %m");
381
382 *llmnr_hostname = TAKE_PTR(n);
383 *full_hostname = TAKE_PTR(h);
384
385 return 0;
386 }
387
388 static const char *fallback_hostname(void) {
389
390 /* Determine the fall back hostname. For exposing this system to the outside world, we cannot have it to be
391 * "localhost" even if that's the compiled in hostname. In this case, let's revert to "linux" instead. */
392
393 if (is_localhost(FALLBACK_HOSTNAME))
394 return "linux";
395
396 return FALLBACK_HOSTNAME;
397 }
398
399 static int make_fallback_hostnames(char **full_hostname, char **llmnr_hostname, char **mdns_hostname) {
400 _cleanup_free_ char *n = NULL, *m = NULL;
401 char label[DNS_LABEL_MAX], *h;
402 const char *p;
403 int r;
404
405 assert(full_hostname);
406 assert(llmnr_hostname);
407 assert(mdns_hostname);
408
409 p = fallback_hostname();
410 r = dns_label_unescape(&p, label, sizeof label, 0);
411 if (r < 0)
412 return log_error_errno(r, "Failed to unescape fallback host name: %m");
413
414 assert(r > 0); /* The fallback hostname must have at least one label */
415
416 r = dns_label_escape_new(label, r, &n);
417 if (r < 0)
418 return log_error_errno(r, "Failed to escape fallback hostname: %m");
419
420 r = dns_name_concat(n, "local", 0, &m);
421 if (r < 0)
422 return log_error_errno(r, "Failed to concatenate mDNS hostname: %m");
423
424 h = strdup(fallback_hostname());
425 if (!h)
426 return log_oom();
427
428 *llmnr_hostname = TAKE_PTR(n);
429 *mdns_hostname = TAKE_PTR(m);
430
431 *full_hostname = h;
432
433 return 0;
434 }
435
436 static int on_hostname_change(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
437 _cleanup_free_ char *full_hostname = NULL, *llmnr_hostname = NULL, *mdns_hostname = NULL;
438 Manager *m = userdata;
439 int r;
440
441 assert(m);
442
443 r = determine_hostname(&full_hostname, &llmnr_hostname, &mdns_hostname);
444 if (r < 0)
445 return 0; /* ignore invalid hostnames */
446
447 if (streq(full_hostname, m->full_hostname) &&
448 streq(llmnr_hostname, m->llmnr_hostname) &&
449 streq(mdns_hostname, m->mdns_hostname))
450 return 0;
451
452 log_info("System hostname changed to '%s'.", full_hostname);
453
454 free_and_replace(m->full_hostname, full_hostname);
455 free_and_replace(m->llmnr_hostname, llmnr_hostname);
456 free_and_replace(m->mdns_hostname, mdns_hostname);
457
458 manager_refresh_rrs(m);
459
460 return 0;
461 }
462
463 static int manager_watch_hostname(Manager *m) {
464 int r;
465
466 assert(m);
467
468 m->hostname_fd = open("/proc/sys/kernel/hostname",
469 O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);
470 if (m->hostname_fd < 0) {
471 log_warning_errno(errno, "Failed to watch hostname: %m");
472 return 0;
473 }
474
475 r = sd_event_add_io(m->event, &m->hostname_event_source, m->hostname_fd, 0, on_hostname_change, m);
476 if (r < 0) {
477 if (r == -EPERM)
478 /* kernels prior to 3.2 don't support polling this file. Ignore the failure. */
479 m->hostname_fd = safe_close(m->hostname_fd);
480 else
481 return log_error_errno(r, "Failed to add hostname event source: %m");
482 }
483
484 (void) sd_event_source_set_description(m->hostname_event_source, "hostname");
485
486 r = determine_hostname(&m->full_hostname, &m->llmnr_hostname, &m->mdns_hostname);
487 if (r < 0) {
488 log_info("Defaulting to hostname '%s'.", fallback_hostname());
489
490 r = make_fallback_hostnames(&m->full_hostname, &m->llmnr_hostname, &m->mdns_hostname);
491 if (r < 0)
492 return r;
493 } else
494 log_info("Using system hostname '%s'.", m->full_hostname);
495
496 return 0;
497 }
498
499 static int manager_sigusr1(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
500 _cleanup_free_ char *buffer = NULL;
501 _cleanup_fclose_ FILE *f = NULL;
502 Manager *m = userdata;
503 DnsServer *server;
504 size_t size = 0;
505 DnsScope *scope;
506 Iterator i;
507 Link *l;
508
509 assert(s);
510 assert(si);
511 assert(m);
512
513 f = open_memstream_unlocked(&buffer, &size);
514 if (!f)
515 return log_oom();
516
517 LIST_FOREACH(scopes, scope, m->dns_scopes)
518 dns_scope_dump(scope, f);
519
520 LIST_FOREACH(servers, server, m->dns_servers)
521 dns_server_dump(server, f);
522 LIST_FOREACH(servers, server, m->fallback_dns_servers)
523 dns_server_dump(server, f);
524 HASHMAP_FOREACH(l, m->links, i)
525 LIST_FOREACH(servers, server, l->dns_servers)
526 dns_server_dump(server, f);
527
528 if (fflush_and_check(f) < 0)
529 return log_oom();
530
531 log_dump(LOG_INFO, buffer);
532 return 0;
533 }
534
535 static int manager_sigusr2(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
536 Manager *m = userdata;
537
538 assert(s);
539 assert(si);
540 assert(m);
541
542 manager_flush_caches(m);
543
544 return 0;
545 }
546
547 static int manager_sigrtmin1(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
548 Manager *m = userdata;
549
550 assert(s);
551 assert(si);
552 assert(m);
553
554 manager_reset_server_features(m);
555 return 0;
556 }
557
558 int manager_new(Manager **ret) {
559 _cleanup_(manager_freep) Manager *m = NULL;
560 int r;
561
562 assert(ret);
563
564 m = new(Manager, 1);
565 if (!m)
566 return -ENOMEM;
567
568 *m = (Manager) {
569 .llmnr_ipv4_udp_fd = -1,
570 .llmnr_ipv6_udp_fd = -1,
571 .llmnr_ipv4_tcp_fd = -1,
572 .llmnr_ipv6_tcp_fd = -1,
573 .mdns_ipv4_fd = -1,
574 .mdns_ipv6_fd = -1,
575 .dns_stub_udp_fd = -1,
576 .dns_stub_tcp_fd = -1,
577 .hostname_fd = -1,
578
579 .llmnr_support = RESOLVE_SUPPORT_YES,
580 .mdns_support = RESOLVE_SUPPORT_YES,
581 .dnssec_mode = DEFAULT_DNSSEC_MODE,
582 .dns_over_tls_mode = DEFAULT_DNS_OVER_TLS_MODE,
583 .enable_cache = true,
584 .dns_stub_listener_mode = DNS_STUB_LISTENER_YES,
585 .read_resolv_conf = true,
586 .need_builtin_fallbacks = true,
587 .etc_hosts_last = USEC_INFINITY,
588 .etc_hosts_mtime = USEC_INFINITY,
589 .read_etc_hosts = true,
590 };
591
592 r = dns_trust_anchor_load(&m->trust_anchor);
593 if (r < 0)
594 return r;
595
596 r = manager_parse_config_file(m);
597 if (r < 0)
598 log_warning_errno(r, "Failed to parse configuration file: %m");
599
600 r = sd_event_default(&m->event);
601 if (r < 0)
602 return r;
603
604 (void) sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL);
605 (void) sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL);
606
607 (void) sd_event_set_watchdog(m->event, true);
608
609 r = manager_watch_hostname(m);
610 if (r < 0)
611 return r;
612
613 r = dnssd_load(m);
614 if (r < 0)
615 log_warning_errno(r, "Failed to load DNS-SD configuration files: %m");
616
617 r = dns_scope_new(m, &m->unicast_scope, NULL, DNS_PROTOCOL_DNS, AF_UNSPEC);
618 if (r < 0)
619 return r;
620
621 r = manager_network_monitor_listen(m);
622 if (r < 0)
623 return r;
624
625 r = manager_rtnl_listen(m);
626 if (r < 0)
627 return r;
628
629 r = manager_connect_bus(m);
630 if (r < 0)
631 return r;
632
633 (void) sd_event_add_signal(m->event, &m->sigusr1_event_source, SIGUSR1, manager_sigusr1, m);
634 (void) sd_event_add_signal(m->event, &m->sigusr2_event_source, SIGUSR2, manager_sigusr2, m);
635 (void) sd_event_add_signal(m->event, &m->sigrtmin1_event_source, SIGRTMIN+1, manager_sigrtmin1, m);
636
637 manager_cleanup_saved_user(m);
638
639 *ret = TAKE_PTR(m);
640
641 return 0;
642 }
643
644 int manager_start(Manager *m) {
645 int r;
646
647 assert(m);
648
649 r = manager_dns_stub_start(m);
650 if (r < 0)
651 return r;
652
653 return 0;
654 }
655
656 Manager *manager_free(Manager *m) {
657 Link *l;
658 DnssdService *s;
659
660 if (!m)
661 return NULL;
662
663 dns_server_unlink_all(m->dns_servers);
664 dns_server_unlink_all(m->fallback_dns_servers);
665 dns_search_domain_unlink_all(m->search_domains);
666
667 while ((l = hashmap_first(m->links)))
668 link_free(l);
669
670 while (m->dns_queries)
671 dns_query_free(m->dns_queries);
672
673 dns_scope_free(m->unicast_scope);
674
675 /* At this point only orphaned streams should remain. All others should have been freed already by their
676 * owners */
677 while (m->dns_streams)
678 dns_stream_unref(m->dns_streams);
679
680 hashmap_free(m->links);
681 hashmap_free(m->dns_transactions);
682
683 sd_event_source_unref(m->network_event_source);
684 sd_network_monitor_unref(m->network_monitor);
685
686 sd_netlink_unref(m->rtnl);
687 sd_event_source_unref(m->rtnl_event_source);
688
689 manager_llmnr_stop(m);
690 manager_mdns_stop(m);
691 manager_dns_stub_stop(m);
692
693 sd_bus_flush_close_unref(m->bus);
694
695 sd_event_source_unref(m->sigusr1_event_source);
696 sd_event_source_unref(m->sigusr2_event_source);
697 sd_event_source_unref(m->sigrtmin1_event_source);
698
699 sd_event_unref(m->event);
700
701 dns_resource_key_unref(m->llmnr_host_ipv4_key);
702 dns_resource_key_unref(m->llmnr_host_ipv6_key);
703 dns_resource_key_unref(m->mdns_host_ipv4_key);
704 dns_resource_key_unref(m->mdns_host_ipv6_key);
705
706 sd_event_source_unref(m->hostname_event_source);
707 safe_close(m->hostname_fd);
708
709 free(m->full_hostname);
710 free(m->llmnr_hostname);
711 free(m->mdns_hostname);
712
713 while ((s = hashmap_first(m->dnssd_services)))
714 dnssd_service_free(s);
715 hashmap_free(m->dnssd_services);
716
717 dns_trust_anchor_flush(&m->trust_anchor);
718 manager_etc_hosts_flush(m);
719
720 return mfree(m);
721 }
722
723 int manager_recv(Manager *m, int fd, DnsProtocol protocol, DnsPacket **ret) {
724 _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
725 union {
726 struct cmsghdr header; /* For alignment */
727 uint8_t buffer[CMSG_SPACE(MAXSIZE(struct in_pktinfo, struct in6_pktinfo))
728 + CMSG_SPACE(int) /* ttl/hoplimit */
729 + EXTRA_CMSG_SPACE /* kernel appears to require extra buffer space */];
730 } control;
731 union sockaddr_union sa;
732 struct iovec iov;
733 struct msghdr mh = {
734 .msg_name = &sa.sa,
735 .msg_namelen = sizeof(sa),
736 .msg_iov = &iov,
737 .msg_iovlen = 1,
738 .msg_control = &control,
739 .msg_controllen = sizeof(control),
740 };
741 struct cmsghdr *cmsg;
742 ssize_t ms, l;
743 int r;
744
745 assert(m);
746 assert(fd >= 0);
747 assert(ret);
748
749 ms = next_datagram_size_fd(fd);
750 if (ms < 0)
751 return ms;
752
753 r = dns_packet_new(&p, protocol, ms, DNS_PACKET_SIZE_MAX);
754 if (r < 0)
755 return r;
756
757 iov = IOVEC_MAKE(DNS_PACKET_DATA(p), p->allocated);
758
759 l = recvmsg(fd, &mh, 0);
760 if (l < 0) {
761 if (IN_SET(errno, EAGAIN, EINTR))
762 return 0;
763
764 return -errno;
765 }
766 if (l == 0)
767 return 0;
768
769 assert(!(mh.msg_flags & MSG_CTRUNC));
770 assert(!(mh.msg_flags & MSG_TRUNC));
771
772 p->size = (size_t) l;
773
774 p->family = sa.sa.sa_family;
775 p->ipproto = IPPROTO_UDP;
776 if (p->family == AF_INET) {
777 p->sender.in = sa.in.sin_addr;
778 p->sender_port = be16toh(sa.in.sin_port);
779 } else if (p->family == AF_INET6) {
780 p->sender.in6 = sa.in6.sin6_addr;
781 p->sender_port = be16toh(sa.in6.sin6_port);
782 p->ifindex = sa.in6.sin6_scope_id;
783 } else
784 return -EAFNOSUPPORT;
785
786 CMSG_FOREACH(cmsg, &mh) {
787
788 if (cmsg->cmsg_level == IPPROTO_IPV6) {
789 assert(p->family == AF_INET6);
790
791 switch (cmsg->cmsg_type) {
792
793 case IPV6_PKTINFO: {
794 struct in6_pktinfo *i = (struct in6_pktinfo*) CMSG_DATA(cmsg);
795
796 if (p->ifindex <= 0)
797 p->ifindex = i->ipi6_ifindex;
798
799 p->destination.in6 = i->ipi6_addr;
800 break;
801 }
802
803 case IPV6_HOPLIMIT:
804 p->ttl = *(int *) CMSG_DATA(cmsg);
805 break;
806
807 }
808 } else if (cmsg->cmsg_level == IPPROTO_IP) {
809 assert(p->family == AF_INET);
810
811 switch (cmsg->cmsg_type) {
812
813 case IP_PKTINFO: {
814 struct in_pktinfo *i = (struct in_pktinfo*) CMSG_DATA(cmsg);
815
816 if (p->ifindex <= 0)
817 p->ifindex = i->ipi_ifindex;
818
819 p->destination.in = i->ipi_addr;
820 break;
821 }
822
823 case IP_TTL:
824 p->ttl = *(int *) CMSG_DATA(cmsg);
825 break;
826 }
827 }
828 }
829
830 /* The Linux kernel sets the interface index to the loopback
831 * device if the packet came from the local host since it
832 * avoids the routing table in such a case. Let's unset the
833 * interface index in such a case. */
834 if (p->ifindex == LOOPBACK_IFINDEX)
835 p->ifindex = 0;
836
837 if (protocol != DNS_PROTOCOL_DNS) {
838 /* If we don't know the interface index still, we look for the
839 * first local interface with a matching address. Yuck! */
840 if (p->ifindex <= 0)
841 p->ifindex = manager_find_ifindex(m, p->family, &p->destination);
842 }
843
844 *ret = TAKE_PTR(p);
845
846 return 1;
847 }
848
849 static int sendmsg_loop(int fd, struct msghdr *mh, int flags) {
850 int r;
851
852 assert(fd >= 0);
853 assert(mh);
854
855 for (;;) {
856 if (sendmsg(fd, mh, flags) >= 0)
857 return 0;
858
859 if (errno == EINTR)
860 continue;
861
862 if (errno != EAGAIN)
863 return -errno;
864
865 r = fd_wait_for_event(fd, POLLOUT, SEND_TIMEOUT_USEC);
866 if (r < 0)
867 return r;
868 if (r == 0)
869 return -ETIMEDOUT;
870 }
871 }
872
873 static int write_loop(int fd, void *message, size_t length) {
874 int r;
875
876 assert(fd >= 0);
877 assert(message);
878
879 for (;;) {
880 if (write(fd, message, length) >= 0)
881 return 0;
882
883 if (errno == EINTR)
884 continue;
885
886 if (errno != EAGAIN)
887 return -errno;
888
889 r = fd_wait_for_event(fd, POLLOUT, SEND_TIMEOUT_USEC);
890 if (r < 0)
891 return r;
892 if (r == 0)
893 return -ETIMEDOUT;
894 }
895 }
896
897 int manager_write(Manager *m, int fd, DnsPacket *p) {
898 int r;
899
900 log_debug("Sending %s packet with id %" PRIu16 ".", DNS_PACKET_QR(p) ? "response" : "query", DNS_PACKET_ID(p));
901
902 r = write_loop(fd, DNS_PACKET_DATA(p), p->size);
903 if (r < 0)
904 return r;
905
906 return 0;
907 }
908
909 static int manager_ipv4_send(
910 Manager *m,
911 int fd,
912 int ifindex,
913 const struct in_addr *destination,
914 uint16_t port,
915 const struct in_addr *source,
916 DnsPacket *p) {
917 union {
918 struct cmsghdr header; /* For alignment */
919 uint8_t buffer[CMSG_SPACE(sizeof(struct in_pktinfo))];
920 } control = {};
921 union sockaddr_union sa;
922 struct iovec iov;
923 struct msghdr mh = {
924 .msg_iov = &iov,
925 .msg_iovlen = 1,
926 .msg_name = &sa.sa,
927 .msg_namelen = sizeof(sa.in),
928 };
929
930 assert(m);
931 assert(fd >= 0);
932 assert(destination);
933 assert(port > 0);
934 assert(p);
935
936 iov = IOVEC_MAKE(DNS_PACKET_DATA(p), p->size);
937
938 sa = (union sockaddr_union) {
939 .in.sin_family = AF_INET,
940 .in.sin_addr = *destination,
941 .in.sin_port = htobe16(port),
942 };
943
944 if (ifindex > 0) {
945 struct cmsghdr *cmsg;
946 struct in_pktinfo *pi;
947
948 mh.msg_control = &control;
949 mh.msg_controllen = CMSG_LEN(sizeof(struct in_pktinfo));
950
951 cmsg = CMSG_FIRSTHDR(&mh);
952 cmsg->cmsg_len = mh.msg_controllen;
953 cmsg->cmsg_level = IPPROTO_IP;
954 cmsg->cmsg_type = IP_PKTINFO;
955
956 pi = (struct in_pktinfo*) CMSG_DATA(cmsg);
957 pi->ipi_ifindex = ifindex;
958
959 if (source)
960 pi->ipi_spec_dst = *source;
961 }
962
963 return sendmsg_loop(fd, &mh, 0);
964 }
965
966 static int manager_ipv6_send(
967 Manager *m,
968 int fd,
969 int ifindex,
970 const struct in6_addr *destination,
971 uint16_t port,
972 const struct in6_addr *source,
973 DnsPacket *p) {
974
975 union {
976 struct cmsghdr header; /* For alignment */
977 uint8_t buffer[CMSG_SPACE(sizeof(struct in6_pktinfo))];
978 } control = {};
979 union sockaddr_union sa;
980 struct iovec iov;
981 struct msghdr mh = {
982 .msg_iov = &iov,
983 .msg_iovlen = 1,
984 .msg_name = &sa.sa,
985 .msg_namelen = sizeof(sa.in6),
986 };
987
988 assert(m);
989 assert(fd >= 0);
990 assert(destination);
991 assert(port > 0);
992 assert(p);
993
994 iov = IOVEC_MAKE(DNS_PACKET_DATA(p), p->size);
995
996 sa = (union sockaddr_union) {
997 .in6.sin6_family = AF_INET6,
998 .in6.sin6_addr = *destination,
999 .in6.sin6_port = htobe16(port),
1000 .in6.sin6_scope_id = ifindex,
1001 };
1002
1003 if (ifindex > 0) {
1004 struct cmsghdr *cmsg;
1005 struct in6_pktinfo *pi;
1006
1007 mh.msg_control = &control;
1008 mh.msg_controllen = CMSG_LEN(sizeof(struct in6_pktinfo));
1009
1010 cmsg = CMSG_FIRSTHDR(&mh);
1011 cmsg->cmsg_len = mh.msg_controllen;
1012 cmsg->cmsg_level = IPPROTO_IPV6;
1013 cmsg->cmsg_type = IPV6_PKTINFO;
1014
1015 pi = (struct in6_pktinfo*) CMSG_DATA(cmsg);
1016 pi->ipi6_ifindex = ifindex;
1017
1018 if (source)
1019 pi->ipi6_addr = *source;
1020 }
1021
1022 return sendmsg_loop(fd, &mh, 0);
1023 }
1024
1025 int manager_send(
1026 Manager *m,
1027 int fd,
1028 int ifindex,
1029 int family,
1030 const union in_addr_union *destination,
1031 uint16_t port,
1032 const union in_addr_union *source,
1033 DnsPacket *p) {
1034
1035 assert(m);
1036 assert(fd >= 0);
1037 assert(destination);
1038 assert(port > 0);
1039 assert(p);
1040
1041 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));
1042
1043 if (family == AF_INET)
1044 return manager_ipv4_send(m, fd, ifindex, &destination->in, port, source ? &source->in : NULL, p);
1045 if (family == AF_INET6)
1046 return manager_ipv6_send(m, fd, ifindex, &destination->in6, port, source ? &source->in6 : NULL, p);
1047
1048 return -EAFNOSUPPORT;
1049 }
1050
1051 uint32_t manager_find_mtu(Manager *m) {
1052 uint32_t mtu = 0;
1053 Link *l;
1054 Iterator i;
1055
1056 /* If we don't know on which link a DNS packet would be
1057 * delivered, let's find the largest MTU that works on all
1058 * interfaces we know of */
1059
1060 HASHMAP_FOREACH(l, m->links, i) {
1061 if (l->mtu <= 0)
1062 continue;
1063
1064 if (mtu <= 0 || l->mtu < mtu)
1065 mtu = l->mtu;
1066 }
1067
1068 return mtu;
1069 }
1070
1071 int manager_find_ifindex(Manager *m, int family, const union in_addr_union *in_addr) {
1072 LinkAddress *a;
1073
1074 assert(m);
1075
1076 a = manager_find_link_address(m, family, in_addr);
1077 if (a)
1078 return a->link->ifindex;
1079
1080 return 0;
1081 }
1082
1083 void manager_refresh_rrs(Manager *m) {
1084 Iterator i;
1085 Link *l;
1086 DnssdService *s;
1087
1088 assert(m);
1089
1090 m->llmnr_host_ipv4_key = dns_resource_key_unref(m->llmnr_host_ipv4_key);
1091 m->llmnr_host_ipv6_key = dns_resource_key_unref(m->llmnr_host_ipv6_key);
1092 m->mdns_host_ipv4_key = dns_resource_key_unref(m->mdns_host_ipv4_key);
1093 m->mdns_host_ipv6_key = dns_resource_key_unref(m->mdns_host_ipv6_key);
1094
1095 if (m->mdns_support == RESOLVE_SUPPORT_YES)
1096 HASHMAP_FOREACH(s, m->dnssd_services, i)
1097 if (dnssd_update_rrs(s) < 0)
1098 log_warning("Failed to refresh DNS-SD service '%s'", s->name);
1099
1100 HASHMAP_FOREACH(l, m->links, i) {
1101 link_add_rrs(l, true);
1102 link_add_rrs(l, false);
1103 }
1104 }
1105
1106 static int manager_next_random_name(const char *old, char **ret_new) {
1107 const char *p;
1108 uint64_t u, a;
1109 char *n;
1110
1111 p = strchr(old, 0);
1112 assert(p);
1113
1114 while (p > old) {
1115 if (!strchr(DIGITS, p[-1]))
1116 break;
1117
1118 p--;
1119 }
1120
1121 if (*p == 0 || safe_atou64(p, &u) < 0 || u <= 0)
1122 u = 1;
1123
1124 /* Add a random number to the old value. This way we can avoid
1125 * that two hosts pick the same hostname, win on IPv4 and lose
1126 * on IPv6 (or vice versa), and pick the same hostname
1127 * replacement hostname, ad infinitum. We still want the
1128 * numbers to go up monotonically, hence we just add a random
1129 * value 1..10 */
1130
1131 random_bytes(&a, sizeof(a));
1132 u += 1 + a % 10;
1133
1134 if (asprintf(&n, "%.*s%" PRIu64, (int) (p - old), old, u) < 0)
1135 return -ENOMEM;
1136
1137 *ret_new = n;
1138
1139 return 0;
1140 }
1141
1142 int manager_next_hostname(Manager *m) {
1143 _cleanup_free_ char *h = NULL, *k = NULL;
1144 int r;
1145
1146 assert(m);
1147
1148 r = manager_next_random_name(m->llmnr_hostname, &h);
1149 if (r < 0)
1150 return r;
1151
1152 r = dns_name_concat(h, "local", 0, &k);
1153 if (r < 0)
1154 return r;
1155
1156 log_info("Hostname conflict, changing published hostname from '%s' to '%s'.", m->llmnr_hostname, h);
1157
1158 free_and_replace(m->llmnr_hostname, h);
1159 free_and_replace(m->mdns_hostname, k);
1160
1161 manager_refresh_rrs(m);
1162
1163 return 0;
1164 }
1165
1166 LinkAddress* manager_find_link_address(Manager *m, int family, const union in_addr_union *in_addr) {
1167 Iterator i;
1168 Link *l;
1169
1170 assert(m);
1171
1172 HASHMAP_FOREACH(l, m->links, i) {
1173 LinkAddress *a;
1174
1175 a = link_find_address(l, family, in_addr);
1176 if (a)
1177 return a;
1178 }
1179
1180 return NULL;
1181 }
1182
1183 bool manager_our_packet(Manager *m, DnsPacket *p) {
1184 assert(m);
1185 assert(p);
1186
1187 return !!manager_find_link_address(m, p->family, &p->sender);
1188 }
1189
1190 DnsScope* manager_find_scope(Manager *m, DnsPacket *p) {
1191 Link *l;
1192
1193 assert(m);
1194 assert(p);
1195
1196 l = hashmap_get(m->links, INT_TO_PTR(p->ifindex));
1197 if (!l)
1198 return NULL;
1199
1200 switch (p->protocol) {
1201 case DNS_PROTOCOL_LLMNR:
1202 if (p->family == AF_INET)
1203 return l->llmnr_ipv4_scope;
1204 else if (p->family == AF_INET6)
1205 return l->llmnr_ipv6_scope;
1206
1207 break;
1208
1209 case DNS_PROTOCOL_MDNS:
1210 if (p->family == AF_INET)
1211 return l->mdns_ipv4_scope;
1212 else if (p->family == AF_INET6)
1213 return l->mdns_ipv6_scope;
1214
1215 break;
1216
1217 default:
1218 break;
1219 }
1220
1221 return NULL;
1222 }
1223
1224 void manager_verify_all(Manager *m) {
1225 DnsScope *s;
1226
1227 assert(m);
1228
1229 LIST_FOREACH(scopes, s, m->dns_scopes)
1230 dns_zone_verify_all(&s->zone);
1231 }
1232
1233 int manager_is_own_hostname(Manager *m, const char *name) {
1234 int r;
1235
1236 assert(m);
1237 assert(name);
1238
1239 if (m->llmnr_hostname) {
1240 r = dns_name_equal(name, m->llmnr_hostname);
1241 if (r != 0)
1242 return r;
1243 }
1244
1245 if (m->mdns_hostname) {
1246 r = dns_name_equal(name, m->mdns_hostname);
1247 if (r != 0)
1248 return r;
1249 }
1250
1251 if (m->full_hostname)
1252 return dns_name_equal(name, m->full_hostname);
1253
1254 return 0;
1255 }
1256
1257 int manager_compile_dns_servers(Manager *m, OrderedSet **dns) {
1258 DnsServer *s;
1259 Iterator i;
1260 Link *l;
1261 int r;
1262
1263 assert(m);
1264 assert(dns);
1265
1266 r = ordered_set_ensure_allocated(dns, &dns_server_hash_ops);
1267 if (r < 0)
1268 return r;
1269
1270 /* First add the system-wide servers and domains */
1271 LIST_FOREACH(servers, s, m->dns_servers) {
1272 r = ordered_set_put(*dns, s);
1273 if (r == -EEXIST)
1274 continue;
1275 if (r < 0)
1276 return r;
1277 }
1278
1279 /* Then, add the per-link servers */
1280 HASHMAP_FOREACH(l, m->links, i) {
1281 LIST_FOREACH(servers, s, l->dns_servers) {
1282 r = ordered_set_put(*dns, s);
1283 if (r == -EEXIST)
1284 continue;
1285 if (r < 0)
1286 return r;
1287 }
1288 }
1289
1290 /* If we found nothing, add the fallback servers */
1291 if (ordered_set_isempty(*dns)) {
1292 LIST_FOREACH(servers, s, m->fallback_dns_servers) {
1293 r = ordered_set_put(*dns, s);
1294 if (r == -EEXIST)
1295 continue;
1296 if (r < 0)
1297 return r;
1298 }
1299 }
1300
1301 return 0;
1302 }
1303
1304 /* filter_route is a tri-state:
1305 * < 0: no filtering
1306 * = 0 or false: return only domains which should be used for searching
1307 * > 0 or true: return only domains which are for routing only
1308 */
1309 int manager_compile_search_domains(Manager *m, OrderedSet **domains, int filter_route) {
1310 DnsSearchDomain *d;
1311 Iterator i;
1312 Link *l;
1313 int r;
1314
1315 assert(m);
1316 assert(domains);
1317
1318 r = ordered_set_ensure_allocated(domains, &dns_name_hash_ops);
1319 if (r < 0)
1320 return r;
1321
1322 LIST_FOREACH(domains, d, m->search_domains) {
1323
1324 if (filter_route >= 0 &&
1325 d->route_only != !!filter_route)
1326 continue;
1327
1328 r = ordered_set_put(*domains, d->name);
1329 if (r == -EEXIST)
1330 continue;
1331 if (r < 0)
1332 return r;
1333 }
1334
1335 HASHMAP_FOREACH(l, m->links, i) {
1336
1337 LIST_FOREACH(domains, d, l->search_domains) {
1338
1339 if (filter_route >= 0 &&
1340 d->route_only != !!filter_route)
1341 continue;
1342
1343 r = ordered_set_put(*domains, d->name);
1344 if (r == -EEXIST)
1345 continue;
1346 if (r < 0)
1347 return r;
1348 }
1349 }
1350
1351 return 0;
1352 }
1353
1354 DnssecMode manager_get_dnssec_mode(Manager *m) {
1355 assert(m);
1356
1357 if (m->dnssec_mode != _DNSSEC_MODE_INVALID)
1358 return m->dnssec_mode;
1359
1360 return DNSSEC_NO;
1361 }
1362
1363 bool manager_dnssec_supported(Manager *m) {
1364 DnsServer *server;
1365 Iterator i;
1366 Link *l;
1367
1368 assert(m);
1369
1370 if (manager_get_dnssec_mode(m) == DNSSEC_NO)
1371 return false;
1372
1373 server = manager_get_dns_server(m);
1374 if (server && !dns_server_dnssec_supported(server))
1375 return false;
1376
1377 HASHMAP_FOREACH(l, m->links, i)
1378 if (!link_dnssec_supported(l))
1379 return false;
1380
1381 return true;
1382 }
1383
1384 DnsOverTlsMode manager_get_dns_over_tls_mode(Manager *m) {
1385 assert(m);
1386
1387 if (m->dns_over_tls_mode != _DNS_OVER_TLS_MODE_INVALID)
1388 return m->dns_over_tls_mode;
1389
1390 return DNS_OVER_TLS_NO;
1391 }
1392
1393 void manager_dnssec_verdict(Manager *m, DnssecVerdict verdict, const DnsResourceKey *key) {
1394
1395 assert(verdict >= 0);
1396 assert(verdict < _DNSSEC_VERDICT_MAX);
1397
1398 if (DEBUG_LOGGING) {
1399 char s[DNS_RESOURCE_KEY_STRING_MAX];
1400
1401 log_debug("Found verdict for lookup %s: %s",
1402 dns_resource_key_to_string(key, s, sizeof s),
1403 dnssec_verdict_to_string(verdict));
1404 }
1405
1406 m->n_dnssec_verdict[verdict]++;
1407 }
1408
1409 bool manager_routable(Manager *m, int family) {
1410 Iterator i;
1411 Link *l;
1412
1413 assert(m);
1414
1415 /* Returns true if the host has at least one interface with a routable address of the specified type */
1416
1417 HASHMAP_FOREACH(l, m->links, i)
1418 if (link_relevant(l, family, false))
1419 return true;
1420
1421 return false;
1422 }
1423
1424 void manager_flush_caches(Manager *m) {
1425 DnsScope *scope;
1426
1427 assert(m);
1428
1429 LIST_FOREACH(scopes, scope, m->dns_scopes)
1430 dns_cache_flush(&scope->cache);
1431
1432 log_info("Flushed all caches.");
1433 }
1434
1435 void manager_reset_server_features(Manager *m) {
1436 Iterator i;
1437 Link *l;
1438
1439 dns_server_reset_features_all(m->dns_servers);
1440 dns_server_reset_features_all(m->fallback_dns_servers);
1441
1442 HASHMAP_FOREACH(l, m->links, i)
1443 dns_server_reset_features_all(l->dns_servers);
1444
1445 log_info("Resetting learnt feature levels on all servers.");
1446 }
1447
1448 void manager_cleanup_saved_user(Manager *m) {
1449 _cleanup_closedir_ DIR *d = NULL;
1450 struct dirent *de;
1451 int r;
1452
1453 assert(m);
1454
1455 /* Clean up all saved per-link files in /run/systemd/resolve/netif/ that don't have a matching interface
1456 * anymore. These files are created to persist settings pushed in by the user via the bus, so that resolved can
1457 * be restarted without losing this data. */
1458
1459 d = opendir("/run/systemd/resolve/netif/");
1460 if (!d) {
1461 if (errno == ENOENT)
1462 return;
1463
1464 log_warning_errno(errno, "Failed to open interface directory: %m");
1465 return;
1466 }
1467
1468 FOREACH_DIRENT_ALL(de, d, log_error_errno(errno, "Failed to read interface directory: %m")) {
1469 _cleanup_free_ char *p = NULL;
1470 int ifindex;
1471 Link *l;
1472
1473 if (!IN_SET(de->d_type, DT_UNKNOWN, DT_REG))
1474 continue;
1475
1476 if (dot_or_dot_dot(de->d_name))
1477 continue;
1478
1479 r = parse_ifindex(de->d_name, &ifindex);
1480 if (r < 0) /* Probably some temporary file from a previous run. Delete it */
1481 goto rm;
1482
1483 l = hashmap_get(m->links, INT_TO_PTR(ifindex));
1484 if (!l) /* link vanished */
1485 goto rm;
1486
1487 if (l->is_managed) /* now managed by networkd, hence the bus settings are useless */
1488 goto rm;
1489
1490 continue;
1491
1492 rm:
1493 p = strappend("/run/systemd/resolve/netif/", de->d_name);
1494 if (!p) {
1495 log_oom();
1496 return;
1497 }
1498
1499 (void) unlink(p);
1500 }
1501 }
1502
1503 bool manager_next_dnssd_names(Manager *m) {
1504 Iterator i;
1505 DnssdService *s;
1506 bool tried = false;
1507 int r;
1508
1509 assert(m);
1510
1511 HASHMAP_FOREACH(s, m->dnssd_services, i) {
1512 _cleanup_free_ char * new_name = NULL;
1513
1514 if (!s->withdrawn)
1515 continue;
1516
1517 r = manager_next_random_name(s->name_template, &new_name);
1518 if (r < 0) {
1519 log_warning_errno(r, "Failed to get new name for service '%s': %m", s->name);
1520 continue;
1521 }
1522
1523 free_and_replace(s->name_template, new_name);
1524
1525 s->withdrawn = false;
1526
1527 tried = true;
1528 }
1529
1530 if (tried)
1531 manager_refresh_rrs(m);
1532
1533 return tried;
1534 }