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1 /***
2 This file is part of systemd.
3
4 Copyright 2014 Tom Gundersen <teg@jklm.no>
5
6 systemd is free software; you can redistribute it and/or modify it
7 under the terms of the GNU Lesser General Public License as published by
8 the Free Software Foundation; either version 2.1 of the License, or
9 (at your option) any later version.
10
11 systemd is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public License
17 along with systemd; If not, see <http://www.gnu.org/licenses/>.
18 ***/
19
20 #include <netinet/in.h>
21 #include <poll.h>
22 #include <sys/ioctl.h>
23
24 #include "af-list.h"
25 #include "alloc-util.h"
26 #include "dns-domain.h"
27 #include "fd-util.h"
28 #include "fileio-label.h"
29 #include "hostname-util.h"
30 #include "io-util.h"
31 #include "netlink-util.h"
32 #include "network-internal.h"
33 #include "ordered-set.h"
34 #include "parse-util.h"
35 #include "random-util.h"
36 #include "resolved-bus.h"
37 #include "resolved-conf.h"
38 #include "resolved-etc-hosts.h"
39 #include "resolved-llmnr.h"
40 #include "resolved-manager.h"
41 #include "resolved-mdns.h"
42 #include "resolved-resolv-conf.h"
43 #include "socket-util.h"
44 #include "string-table.h"
45 #include "string-util.h"
46 #include "utf8.h"
47
48 #define SEND_TIMEOUT_USEC (200 * USEC_PER_MSEC)
49
50 static int manager_process_link(sd_netlink *rtnl, sd_netlink_message *mm, void *userdata) {
51 Manager *m = userdata;
52 uint16_t type;
53 Link *l;
54 int ifindex, r;
55
56 assert(rtnl);
57 assert(m);
58 assert(mm);
59
60 r = sd_netlink_message_get_type(mm, &type);
61 if (r < 0)
62 goto fail;
63
64 r = sd_rtnl_message_link_get_ifindex(mm, &ifindex);
65 if (r < 0)
66 goto fail;
67
68 l = hashmap_get(m->links, INT_TO_PTR(ifindex));
69
70 switch (type) {
71
72 case RTM_NEWLINK:{
73 bool is_new = !l;
74
75 if (!l) {
76 r = link_new(m, &l, ifindex);
77 if (r < 0)
78 goto fail;
79 }
80
81 r = link_update_rtnl(l, mm);
82 if (r < 0)
83 goto fail;
84
85 r = link_update_monitor(l);
86 if (r < 0)
87 goto fail;
88
89 if (is_new)
90 log_debug("Found new link %i/%s", ifindex, l->name);
91
92 break;
93 }
94
95 case RTM_DELLINK:
96 if (l) {
97 log_debug("Removing link %i/%s", l->ifindex, l->name);
98 link_free(l);
99 }
100
101 break;
102 }
103
104 return 0;
105
106 fail:
107 log_warning_errno(r, "Failed to process RTNL link message: %m");
108 return 0;
109 }
110
111 static int manager_process_address(sd_netlink *rtnl, sd_netlink_message *mm, void *userdata) {
112 Manager *m = userdata;
113 union in_addr_union address;
114 uint16_t type;
115 int r, ifindex, family;
116 LinkAddress *a;
117 Link *l;
118
119 assert(rtnl);
120 assert(mm);
121 assert(m);
122
123 r = sd_netlink_message_get_type(mm, &type);
124 if (r < 0)
125 goto fail;
126
127 r = sd_rtnl_message_addr_get_ifindex(mm, &ifindex);
128 if (r < 0)
129 goto fail;
130
131 l = hashmap_get(m->links, INT_TO_PTR(ifindex));
132 if (!l)
133 return 0;
134
135 r = sd_rtnl_message_addr_get_family(mm, &family);
136 if (r < 0)
137 goto fail;
138
139 switch (family) {
140
141 case AF_INET:
142 r = sd_netlink_message_read_in_addr(mm, IFA_LOCAL, &address.in);
143 if (r < 0) {
144 r = sd_netlink_message_read_in_addr(mm, IFA_ADDRESS, &address.in);
145 if (r < 0)
146 goto fail;
147 }
148
149 break;
150
151 case AF_INET6:
152 r = sd_netlink_message_read_in6_addr(mm, IFA_LOCAL, &address.in6);
153 if (r < 0) {
154 r = sd_netlink_message_read_in6_addr(mm, IFA_ADDRESS, &address.in6);
155 if (r < 0)
156 goto fail;
157 }
158
159 break;
160
161 default:
162 return 0;
163 }
164
165 a = link_find_address(l, family, &address);
166
167 switch (type) {
168
169 case RTM_NEWADDR:
170
171 if (!a) {
172 r = link_address_new(l, &a, family, &address);
173 if (r < 0)
174 return r;
175 }
176
177 r = link_address_update_rtnl(a, mm);
178 if (r < 0)
179 return r;
180
181 break;
182
183 case RTM_DELADDR:
184 link_address_free(a);
185 break;
186 }
187
188 return 0;
189
190 fail:
191 log_warning_errno(r, "Failed to process RTNL address message: %m");
192 return 0;
193 }
194
195 static int manager_rtnl_listen(Manager *m) {
196 _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
197 sd_netlink_message *i;
198 int r;
199
200 assert(m);
201
202 /* First, subscribe to interfaces coming and going */
203 r = sd_netlink_open(&m->rtnl);
204 if (r < 0)
205 return r;
206
207 r = sd_netlink_attach_event(m->rtnl, m->event, SD_EVENT_PRIORITY_IMPORTANT);
208 if (r < 0)
209 return r;
210
211 r = sd_netlink_add_match(m->rtnl, RTM_NEWLINK, manager_process_link, m);
212 if (r < 0)
213 return r;
214
215 r = sd_netlink_add_match(m->rtnl, RTM_DELLINK, manager_process_link, m);
216 if (r < 0)
217 return r;
218
219 r = sd_netlink_add_match(m->rtnl, RTM_NEWADDR, manager_process_address, m);
220 if (r < 0)
221 return r;
222
223 r = sd_netlink_add_match(m->rtnl, RTM_DELADDR, manager_process_address, m);
224 if (r < 0)
225 return r;
226
227 /* Then, enumerate all links */
228 r = sd_rtnl_message_new_link(m->rtnl, &req, RTM_GETLINK, 0);
229 if (r < 0)
230 return r;
231
232 r = sd_netlink_message_request_dump(req, true);
233 if (r < 0)
234 return r;
235
236 r = sd_netlink_call(m->rtnl, req, 0, &reply);
237 if (r < 0)
238 return r;
239
240 for (i = reply; i; i = sd_netlink_message_next(i)) {
241 r = manager_process_link(m->rtnl, i, m);
242 if (r < 0)
243 return r;
244 }
245
246 req = sd_netlink_message_unref(req);
247 reply = sd_netlink_message_unref(reply);
248
249 /* Finally, enumerate all addresses, too */
250 r = sd_rtnl_message_new_addr(m->rtnl, &req, RTM_GETADDR, 0, AF_UNSPEC);
251 if (r < 0)
252 return r;
253
254 r = sd_netlink_message_request_dump(req, true);
255 if (r < 0)
256 return r;
257
258 r = sd_netlink_call(m->rtnl, req, 0, &reply);
259 if (r < 0)
260 return r;
261
262 for (i = reply; i; i = sd_netlink_message_next(i)) {
263 r = manager_process_address(m->rtnl, i, m);
264 if (r < 0)
265 return r;
266 }
267
268 return r;
269 }
270
271 static int on_network_event(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
272 Manager *m = userdata;
273 Iterator i;
274 Link *l;
275 int r;
276
277 assert(m);
278
279 sd_network_monitor_flush(m->network_monitor);
280
281 HASHMAP_FOREACH(l, m->links, i) {
282 r = link_update_monitor(l);
283 if (r < 0)
284 log_warning_errno(r, "Failed to update monitor information for %i: %m", l->ifindex);
285 }
286
287 (void) manager_write_resolv_conf(m);
288
289 return 0;
290 }
291
292 static int manager_network_monitor_listen(Manager *m) {
293 int r, fd, events;
294
295 assert(m);
296
297 r = sd_network_monitor_new(&m->network_monitor, NULL);
298 if (r < 0)
299 return r;
300
301 fd = sd_network_monitor_get_fd(m->network_monitor);
302 if (fd < 0)
303 return fd;
304
305 events = sd_network_monitor_get_events(m->network_monitor);
306 if (events < 0)
307 return events;
308
309 r = sd_event_add_io(m->event, &m->network_event_source, fd, events, &on_network_event, m);
310 if (r < 0)
311 return r;
312
313 r = sd_event_source_set_priority(m->network_event_source, SD_EVENT_PRIORITY_IMPORTANT+5);
314 if (r < 0)
315 return r;
316
317 (void) sd_event_source_set_description(m->network_event_source, "network-monitor");
318
319 return 0;
320 }
321
322 static int determine_hostname(char **llmnr_hostname, char **mdns_hostname) {
323 _cleanup_free_ char *h = NULL, *n = NULL;
324 char label[DNS_LABEL_MAX];
325 const char *p;
326 int r, k;
327
328 assert(llmnr_hostname);
329 assert(mdns_hostname);
330
331 /* Extract and normalize the first label of the locally
332 * configured hostname, and check it's not "localhost". */
333
334 h = gethostname_malloc();
335 if (!h)
336 return log_oom();
337
338 p = h;
339 r = dns_label_unescape(&p, label, sizeof(label));
340 if (r < 0)
341 return log_error_errno(r, "Failed to unescape host name: %m");
342 if (r == 0) {
343 log_error("Couldn't find a single label in hosntame.");
344 return -EINVAL;
345 }
346
347 k = dns_label_undo_idna(label, r, label, sizeof(label));
348 if (k < 0)
349 return log_error_errno(k, "Failed to undo IDNA: %m");
350 if (k > 0)
351 r = k;
352
353 if (!utf8_is_valid(label)) {
354 log_error("System hostname is not UTF-8 clean.");
355 return -EINVAL;
356 }
357
358 r = dns_label_escape_new(label, r, &n);
359 if (r < 0)
360 return log_error_errno(r, "Failed to escape host name: %m");
361
362 if (is_localhost(n)) {
363 log_debug("System hostname is 'localhost', ignoring.");
364 return -EINVAL;
365 }
366
367 r = dns_name_concat(n, "local", mdns_hostname);
368 if (r < 0)
369 return log_error_errno(r, "Failed to determine mDNS hostname: %m");
370
371 *llmnr_hostname = n;
372 n = NULL;
373
374 return 0;
375 }
376
377 static int on_hostname_change(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
378 _cleanup_free_ char *llmnr_hostname = NULL, *mdns_hostname = NULL;
379 Manager *m = userdata;
380 int r;
381
382 assert(m);
383
384 r = determine_hostname(&llmnr_hostname, &mdns_hostname);
385 if (r < 0)
386 return 0; /* ignore invalid hostnames */
387
388 if (streq(llmnr_hostname, m->llmnr_hostname) && streq(mdns_hostname, m->mdns_hostname))
389 return 0;
390
391 log_info("System hostname changed to '%s'.", llmnr_hostname);
392
393 free(m->llmnr_hostname);
394 free(m->mdns_hostname);
395
396 m->llmnr_hostname = llmnr_hostname;
397 m->mdns_hostname = mdns_hostname;
398
399 llmnr_hostname = mdns_hostname = NULL;
400
401 manager_refresh_rrs(m);
402
403 return 0;
404 }
405
406 static int manager_watch_hostname(Manager *m) {
407 int r;
408
409 assert(m);
410
411 m->hostname_fd = open("/proc/sys/kernel/hostname", O_RDONLY|O_CLOEXEC|O_NDELAY|O_NOCTTY);
412 if (m->hostname_fd < 0) {
413 log_warning_errno(errno, "Failed to watch hostname: %m");
414 return 0;
415 }
416
417 r = sd_event_add_io(m->event, &m->hostname_event_source, m->hostname_fd, 0, on_hostname_change, m);
418 if (r < 0) {
419 if (r == -EPERM)
420 /* kernels prior to 3.2 don't support polling this file. Ignore the failure. */
421 m->hostname_fd = safe_close(m->hostname_fd);
422 else
423 return log_error_errno(r, "Failed to add hostname event source: %m");
424 }
425
426 (void) sd_event_source_set_description(m->hostname_event_source, "hostname");
427
428 r = determine_hostname(&m->llmnr_hostname, &m->mdns_hostname);
429 if (r < 0) {
430 log_info("Defaulting to hostname 'linux'.");
431 m->llmnr_hostname = strdup("linux");
432 if (!m->llmnr_hostname)
433 return log_oom();
434
435 m->mdns_hostname = strdup("linux.local");
436 if (!m->mdns_hostname)
437 return log_oom();
438 } else
439 log_info("Using system hostname '%s'.", m->llmnr_hostname);
440
441 return 0;
442 }
443
444 static int manager_sigusr1(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
445 _cleanup_free_ char *buffer = NULL;
446 _cleanup_fclose_ FILE *f = NULL;
447 Manager *m = userdata;
448 size_t size = 0;
449 DnsScope *scope;
450
451 assert(s);
452 assert(si);
453 assert(m);
454
455 f = open_memstream(&buffer, &size);
456 if (!f)
457 return log_oom();
458
459 LIST_FOREACH(scopes, scope, m->dns_scopes)
460 dns_scope_dump(scope, f);
461
462 if (fflush_and_check(f) < 0)
463 return log_oom();
464
465 log_dump(LOG_INFO, buffer);
466 return 0;
467 }
468
469 static int manager_sigusr2(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
470 Manager *m = userdata;
471
472 assert(s);
473 assert(si);
474 assert(m);
475
476 manager_flush_caches(m);
477
478 return 0;
479 }
480
481 int manager_new(Manager **ret) {
482 _cleanup_(manager_freep) Manager *m = NULL;
483 int r;
484
485 assert(ret);
486
487 m = new0(Manager, 1);
488 if (!m)
489 return -ENOMEM;
490
491 m->llmnr_ipv4_udp_fd = m->llmnr_ipv6_udp_fd = -1;
492 m->llmnr_ipv4_tcp_fd = m->llmnr_ipv6_tcp_fd = -1;
493 m->mdns_ipv4_fd = m->mdns_ipv6_fd = -1;
494 m->hostname_fd = -1;
495
496 m->llmnr_support = RESOLVE_SUPPORT_YES;
497 m->mdns_support = RESOLVE_SUPPORT_NO;
498 m->dnssec_mode = DEFAULT_DNSSEC_MODE;
499 m->read_resolv_conf = true;
500 m->need_builtin_fallbacks = true;
501 m->etc_hosts_last = m->etc_hosts_mtime = USEC_INFINITY;
502
503 r = dns_trust_anchor_load(&m->trust_anchor);
504 if (r < 0)
505 return r;
506
507 r = manager_parse_config_file(m);
508 if (r < 0)
509 return r;
510
511 r = sd_event_default(&m->event);
512 if (r < 0)
513 return r;
514
515 sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL);
516 sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL);
517
518 sd_event_set_watchdog(m->event, true);
519
520 r = manager_watch_hostname(m);
521 if (r < 0)
522 return r;
523
524 r = dns_scope_new(m, &m->unicast_scope, NULL, DNS_PROTOCOL_DNS, AF_UNSPEC);
525 if (r < 0)
526 return r;
527
528 r = manager_network_monitor_listen(m);
529 if (r < 0)
530 return r;
531
532 r = manager_rtnl_listen(m);
533 if (r < 0)
534 return r;
535
536 r = manager_connect_bus(m);
537 if (r < 0)
538 return r;
539
540 (void) sd_event_add_signal(m->event, &m->sigusr1_event_source, SIGUSR1, manager_sigusr1, m);
541 (void) sd_event_add_signal(m->event, &m->sigusr2_event_source, SIGUSR2, manager_sigusr2, m);
542
543 *ret = m;
544 m = NULL;
545
546 return 0;
547 }
548
549 int manager_start(Manager *m) {
550 int r;
551
552 assert(m);
553
554 r = manager_llmnr_start(m);
555 if (r < 0)
556 return r;
557
558 r = manager_mdns_start(m);
559 if (r < 0)
560 return r;
561
562 return 0;
563 }
564
565 Manager *manager_free(Manager *m) {
566 Link *l;
567
568 if (!m)
569 return NULL;
570
571 dns_server_unlink_all(m->dns_servers);
572 dns_server_unlink_all(m->fallback_dns_servers);
573 dns_search_domain_unlink_all(m->search_domains);
574
575 while ((l = hashmap_first(m->links)))
576 link_free(l);
577
578 while (m->dns_queries)
579 dns_query_free(m->dns_queries);
580
581 dns_scope_free(m->unicast_scope);
582
583 hashmap_free(m->links);
584 hashmap_free(m->dns_transactions);
585
586 sd_event_source_unref(m->network_event_source);
587 sd_network_monitor_unref(m->network_monitor);
588
589 sd_netlink_unref(m->rtnl);
590 sd_event_source_unref(m->rtnl_event_source);
591
592 manager_llmnr_stop(m);
593 manager_mdns_stop(m);
594
595 sd_bus_slot_unref(m->prepare_for_sleep_slot);
596 sd_event_source_unref(m->bus_retry_event_source);
597 sd_bus_unref(m->bus);
598
599 sd_event_source_unref(m->sigusr1_event_source);
600 sd_event_source_unref(m->sigusr2_event_source);
601
602 sd_event_unref(m->event);
603
604 dns_resource_key_unref(m->llmnr_host_ipv4_key);
605 dns_resource_key_unref(m->llmnr_host_ipv6_key);
606
607 sd_event_source_unref(m->hostname_event_source);
608 safe_close(m->hostname_fd);
609 free(m->llmnr_hostname);
610 free(m->mdns_hostname);
611
612 dns_trust_anchor_flush(&m->trust_anchor);
613 manager_etc_hosts_flush(m);
614
615 free(m);
616
617 return NULL;
618 }
619
620 int manager_recv(Manager *m, int fd, DnsProtocol protocol, DnsPacket **ret) {
621 _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
622 union {
623 struct cmsghdr header; /* For alignment */
624 uint8_t buffer[CMSG_SPACE(MAXSIZE(struct in_pktinfo, struct in6_pktinfo))
625 + CMSG_SPACE(int) /* ttl/hoplimit */
626 + EXTRA_CMSG_SPACE /* kernel appears to require extra buffer space */];
627 } control;
628 union sockaddr_union sa;
629 struct msghdr mh = {};
630 struct cmsghdr *cmsg;
631 struct iovec iov;
632 ssize_t ms, l;
633 int r;
634
635 assert(m);
636 assert(fd >= 0);
637 assert(ret);
638
639 ms = next_datagram_size_fd(fd);
640 if (ms < 0)
641 return ms;
642
643 r = dns_packet_new(&p, protocol, ms);
644 if (r < 0)
645 return r;
646
647 iov.iov_base = DNS_PACKET_DATA(p);
648 iov.iov_len = p->allocated;
649
650 mh.msg_name = &sa.sa;
651 mh.msg_namelen = sizeof(sa);
652 mh.msg_iov = &iov;
653 mh.msg_iovlen = 1;
654 mh.msg_control = &control;
655 mh.msg_controllen = sizeof(control);
656
657 l = recvmsg(fd, &mh, 0);
658 if (l == 0)
659 return 0;
660 if (l < 0) {
661 if (errno == EAGAIN || errno == EINTR)
662 return 0;
663
664 return -errno;
665 }
666
667 assert(!(mh.msg_flags & MSG_CTRUNC));
668 assert(!(mh.msg_flags & MSG_TRUNC));
669
670 p->size = (size_t) l;
671
672 p->family = sa.sa.sa_family;
673 p->ipproto = IPPROTO_UDP;
674 if (p->family == AF_INET) {
675 p->sender.in = sa.in.sin_addr;
676 p->sender_port = be16toh(sa.in.sin_port);
677 } else if (p->family == AF_INET6) {
678 p->sender.in6 = sa.in6.sin6_addr;
679 p->sender_port = be16toh(sa.in6.sin6_port);
680 p->ifindex = sa.in6.sin6_scope_id;
681 } else
682 return -EAFNOSUPPORT;
683
684 CMSG_FOREACH(cmsg, &mh) {
685
686 if (cmsg->cmsg_level == IPPROTO_IPV6) {
687 assert(p->family == AF_INET6);
688
689 switch (cmsg->cmsg_type) {
690
691 case IPV6_PKTINFO: {
692 struct in6_pktinfo *i = (struct in6_pktinfo*) CMSG_DATA(cmsg);
693
694 if (p->ifindex <= 0)
695 p->ifindex = i->ipi6_ifindex;
696
697 p->destination.in6 = i->ipi6_addr;
698 break;
699 }
700
701 case IPV6_HOPLIMIT:
702 p->ttl = *(int *) CMSG_DATA(cmsg);
703 break;
704
705 }
706 } else if (cmsg->cmsg_level == IPPROTO_IP) {
707 assert(p->family == AF_INET);
708
709 switch (cmsg->cmsg_type) {
710
711 case IP_PKTINFO: {
712 struct in_pktinfo *i = (struct in_pktinfo*) CMSG_DATA(cmsg);
713
714 if (p->ifindex <= 0)
715 p->ifindex = i->ipi_ifindex;
716
717 p->destination.in = i->ipi_addr;
718 break;
719 }
720
721 case IP_TTL:
722 p->ttl = *(int *) CMSG_DATA(cmsg);
723 break;
724 }
725 }
726 }
727
728 /* The Linux kernel sets the interface index to the loopback
729 * device if the packet came from the local host since it
730 * avoids the routing table in such a case. Let's unset the
731 * interface index in such a case. */
732 if (p->ifindex == LOOPBACK_IFINDEX)
733 p->ifindex = 0;
734
735 if (protocol != DNS_PROTOCOL_DNS) {
736 /* If we don't know the interface index still, we look for the
737 * first local interface with a matching address. Yuck! */
738 if (p->ifindex <= 0)
739 p->ifindex = manager_find_ifindex(m, p->family, &p->destination);
740 }
741
742 *ret = p;
743 p = NULL;
744
745 return 1;
746 }
747
748 static int sendmsg_loop(int fd, struct msghdr *mh, int flags) {
749 int r;
750
751 assert(fd >= 0);
752 assert(mh);
753
754 for (;;) {
755 if (sendmsg(fd, mh, flags) >= 0)
756 return 0;
757
758 if (errno == EINTR)
759 continue;
760
761 if (errno != EAGAIN)
762 return -errno;
763
764 r = fd_wait_for_event(fd, POLLOUT, SEND_TIMEOUT_USEC);
765 if (r < 0)
766 return r;
767 if (r == 0)
768 return -ETIMEDOUT;
769 }
770 }
771
772 static int write_loop(int fd, void *message, size_t length) {
773 int r;
774
775 assert(fd >= 0);
776 assert(message);
777
778 for (;;) {
779 if (write(fd, message, length) >= 0)
780 return 0;
781
782 if (errno == EINTR)
783 continue;
784
785 if (errno != EAGAIN)
786 return -errno;
787
788 r = fd_wait_for_event(fd, POLLOUT, SEND_TIMEOUT_USEC);
789 if (r < 0)
790 return r;
791 if (r == 0)
792 return -ETIMEDOUT;
793 }
794 }
795
796 int manager_write(Manager *m, int fd, DnsPacket *p) {
797 int r;
798
799 log_debug("Sending %s packet with id %" PRIu16 ".", DNS_PACKET_QR(p) ? "response" : "query", DNS_PACKET_ID(p));
800
801 r = write_loop(fd, DNS_PACKET_DATA(p), p->size);
802 if (r < 0)
803 return r;
804
805 return 0;
806 }
807
808 static int manager_ipv4_send(Manager *m, int fd, int ifindex, const struct in_addr *addr, uint16_t port, DnsPacket *p) {
809 union sockaddr_union sa = {
810 .in.sin_family = AF_INET,
811 };
812 union {
813 struct cmsghdr header; /* For alignment */
814 uint8_t buffer[CMSG_SPACE(sizeof(struct in_pktinfo))];
815 } control;
816 struct msghdr mh = {};
817 struct iovec iov;
818
819 assert(m);
820 assert(fd >= 0);
821 assert(addr);
822 assert(port > 0);
823 assert(p);
824
825 iov.iov_base = DNS_PACKET_DATA(p);
826 iov.iov_len = p->size;
827
828 sa.in.sin_addr = *addr;
829 sa.in.sin_port = htobe16(port),
830
831 mh.msg_iov = &iov;
832 mh.msg_iovlen = 1;
833 mh.msg_name = &sa.sa;
834 mh.msg_namelen = sizeof(sa.in);
835
836 if (ifindex > 0) {
837 struct cmsghdr *cmsg;
838 struct in_pktinfo *pi;
839
840 zero(control);
841
842 mh.msg_control = &control;
843 mh.msg_controllen = CMSG_LEN(sizeof(struct in_pktinfo));
844
845 cmsg = CMSG_FIRSTHDR(&mh);
846 cmsg->cmsg_len = mh.msg_controllen;
847 cmsg->cmsg_level = IPPROTO_IP;
848 cmsg->cmsg_type = IP_PKTINFO;
849
850 pi = (struct in_pktinfo*) CMSG_DATA(cmsg);
851 pi->ipi_ifindex = ifindex;
852 }
853
854 return sendmsg_loop(fd, &mh, 0);
855 }
856
857 static int manager_ipv6_send(Manager *m, int fd, int ifindex, const struct in6_addr *addr, uint16_t port, DnsPacket *p) {
858 union sockaddr_union sa = {
859 .in6.sin6_family = AF_INET6,
860 };
861 union {
862 struct cmsghdr header; /* For alignment */
863 uint8_t buffer[CMSG_SPACE(sizeof(struct in6_pktinfo))];
864 } control;
865 struct msghdr mh = {};
866 struct iovec iov;
867
868 assert(m);
869 assert(fd >= 0);
870 assert(addr);
871 assert(port > 0);
872 assert(p);
873
874 iov.iov_base = DNS_PACKET_DATA(p);
875 iov.iov_len = p->size;
876
877 sa.in6.sin6_addr = *addr;
878 sa.in6.sin6_port = htobe16(port),
879 sa.in6.sin6_scope_id = ifindex;
880
881 mh.msg_iov = &iov;
882 mh.msg_iovlen = 1;
883 mh.msg_name = &sa.sa;
884 mh.msg_namelen = sizeof(sa.in6);
885
886 if (ifindex > 0) {
887 struct cmsghdr *cmsg;
888 struct in6_pktinfo *pi;
889
890 zero(control);
891
892 mh.msg_control = &control;
893 mh.msg_controllen = CMSG_LEN(sizeof(struct in6_pktinfo));
894
895 cmsg = CMSG_FIRSTHDR(&mh);
896 cmsg->cmsg_len = mh.msg_controllen;
897 cmsg->cmsg_level = IPPROTO_IPV6;
898 cmsg->cmsg_type = IPV6_PKTINFO;
899
900 pi = (struct in6_pktinfo*) CMSG_DATA(cmsg);
901 pi->ipi6_ifindex = ifindex;
902 }
903
904 return sendmsg_loop(fd, &mh, 0);
905 }
906
907 int manager_send(Manager *m, int fd, int ifindex, int family, const union in_addr_union *addr, uint16_t port, DnsPacket *p) {
908 assert(m);
909 assert(fd >= 0);
910 assert(addr);
911 assert(port > 0);
912 assert(p);
913
914 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));
915
916 if (family == AF_INET)
917 return manager_ipv4_send(m, fd, ifindex, &addr->in, port, p);
918 if (family == AF_INET6)
919 return manager_ipv6_send(m, fd, ifindex, &addr->in6, port, p);
920
921 return -EAFNOSUPPORT;
922 }
923
924 uint32_t manager_find_mtu(Manager *m) {
925 uint32_t mtu = 0;
926 Link *l;
927 Iterator i;
928
929 /* If we don't know on which link a DNS packet would be
930 * delivered, let's find the largest MTU that works on all
931 * interfaces we know of */
932
933 HASHMAP_FOREACH(l, m->links, i) {
934 if (l->mtu <= 0)
935 continue;
936
937 if (mtu <= 0 || l->mtu < mtu)
938 mtu = l->mtu;
939 }
940
941 return mtu;
942 }
943
944 int manager_find_ifindex(Manager *m, int family, const union in_addr_union *in_addr) {
945 LinkAddress *a;
946
947 assert(m);
948
949 a = manager_find_link_address(m, family, in_addr);
950 if (a)
951 return a->link->ifindex;
952
953 return 0;
954 }
955
956 void manager_refresh_rrs(Manager *m) {
957 Iterator i;
958 Link *l;
959
960 assert(m);
961
962 m->llmnr_host_ipv4_key = dns_resource_key_unref(m->llmnr_host_ipv4_key);
963 m->llmnr_host_ipv6_key = dns_resource_key_unref(m->llmnr_host_ipv6_key);
964
965 HASHMAP_FOREACH(l, m->links, i) {
966 link_add_rrs(l, true);
967 link_add_rrs(l, false);
968 }
969 }
970
971 int manager_next_hostname(Manager *m) {
972 const char *p;
973 uint64_t u, a;
974 char *h, *k;
975 int r;
976
977 assert(m);
978
979 p = strchr(m->llmnr_hostname, 0);
980 assert(p);
981
982 while (p > m->llmnr_hostname) {
983 if (!strchr("0123456789", p[-1]))
984 break;
985
986 p--;
987 }
988
989 if (*p == 0 || safe_atou64(p, &u) < 0 || u <= 0)
990 u = 1;
991
992 /* Add a random number to the old value. This way we can avoid
993 * that two hosts pick the same hostname, win on IPv4 and lose
994 * on IPv6 (or vice versa), and pick the same hostname
995 * replacement hostname, ad infinitum. We still want the
996 * numbers to go up monotonically, hence we just add a random
997 * value 1..10 */
998
999 random_bytes(&a, sizeof(a));
1000 u += 1 + a % 10;
1001
1002 if (asprintf(&h, "%.*s%" PRIu64, (int) (p - m->llmnr_hostname), m->llmnr_hostname, u) < 0)
1003 return -ENOMEM;
1004
1005 r = dns_name_concat(h, "local", &k);
1006 if (r < 0) {
1007 free(h);
1008 return r;
1009 }
1010
1011 log_info("Hostname conflict, changing published hostname from '%s' to '%s'.", m->llmnr_hostname, h);
1012
1013 free(m->llmnr_hostname);
1014 m->llmnr_hostname = h;
1015
1016 free(m->mdns_hostname);
1017 m->mdns_hostname = k;
1018
1019 manager_refresh_rrs(m);
1020
1021 return 0;
1022 }
1023
1024 LinkAddress* manager_find_link_address(Manager *m, int family, const union in_addr_union *in_addr) {
1025 Iterator i;
1026 Link *l;
1027
1028 assert(m);
1029
1030 HASHMAP_FOREACH(l, m->links, i) {
1031 LinkAddress *a;
1032
1033 a = link_find_address(l, family, in_addr);
1034 if (a)
1035 return a;
1036 }
1037
1038 return NULL;
1039 }
1040
1041 bool manager_our_packet(Manager *m, DnsPacket *p) {
1042 assert(m);
1043 assert(p);
1044
1045 return !!manager_find_link_address(m, p->family, &p->sender);
1046 }
1047
1048 DnsScope* manager_find_scope(Manager *m, DnsPacket *p) {
1049 Link *l;
1050
1051 assert(m);
1052 assert(p);
1053
1054 l = hashmap_get(m->links, INT_TO_PTR(p->ifindex));
1055 if (!l)
1056 return NULL;
1057
1058 switch (p->protocol) {
1059 case DNS_PROTOCOL_LLMNR:
1060 if (p->family == AF_INET)
1061 return l->llmnr_ipv4_scope;
1062 else if (p->family == AF_INET6)
1063 return l->llmnr_ipv6_scope;
1064
1065 break;
1066
1067 case DNS_PROTOCOL_MDNS:
1068 if (p->family == AF_INET)
1069 return l->mdns_ipv4_scope;
1070 else if (p->family == AF_INET6)
1071 return l->mdns_ipv6_scope;
1072
1073 break;
1074
1075 default:
1076 break;
1077 }
1078
1079 return NULL;
1080 }
1081
1082 void manager_verify_all(Manager *m) {
1083 DnsScope *s;
1084
1085 assert(m);
1086
1087 LIST_FOREACH(scopes, s, m->dns_scopes)
1088 dns_zone_verify_all(&s->zone);
1089 }
1090
1091 int manager_is_own_hostname(Manager *m, const char *name) {
1092 int r;
1093
1094 assert(m);
1095 assert(name);
1096
1097 if (m->llmnr_hostname) {
1098 r = dns_name_equal(name, m->llmnr_hostname);
1099 if (r != 0)
1100 return r;
1101 }
1102
1103 if (m->mdns_hostname)
1104 return dns_name_equal(name, m->mdns_hostname);
1105
1106 return 0;
1107 }
1108
1109 int manager_compile_dns_servers(Manager *m, OrderedSet **dns) {
1110 DnsServer *s;
1111 Iterator i;
1112 Link *l;
1113 int r;
1114
1115 assert(m);
1116 assert(dns);
1117
1118 r = ordered_set_ensure_allocated(dns, &dns_server_hash_ops);
1119 if (r < 0)
1120 return r;
1121
1122 /* First add the system-wide servers and domains */
1123 LIST_FOREACH(servers, s, m->dns_servers) {
1124 r = ordered_set_put(*dns, s);
1125 if (r == -EEXIST)
1126 continue;
1127 if (r < 0)
1128 return r;
1129 }
1130
1131 /* Then, add the per-link servers */
1132 HASHMAP_FOREACH(l, m->links, i) {
1133 LIST_FOREACH(servers, s, l->dns_servers) {
1134 r = ordered_set_put(*dns, s);
1135 if (r == -EEXIST)
1136 continue;
1137 if (r < 0)
1138 return r;
1139 }
1140 }
1141
1142 /* If we found nothing, add the fallback servers */
1143 if (ordered_set_isempty(*dns)) {
1144 LIST_FOREACH(servers, s, m->fallback_dns_servers) {
1145 r = ordered_set_put(*dns, s);
1146 if (r == -EEXIST)
1147 continue;
1148 if (r < 0)
1149 return r;
1150 }
1151 }
1152
1153 return 0;
1154 }
1155
1156 int manager_compile_search_domains(Manager *m, OrderedSet **domains, int filter_route) {
1157 DnsSearchDomain *d;
1158 Iterator i;
1159 Link *l;
1160 int r;
1161
1162 assert(m);
1163 assert(domains);
1164
1165 r = ordered_set_ensure_allocated(domains, &dns_name_hash_ops);
1166 if (r < 0)
1167 return r;
1168
1169 LIST_FOREACH(domains, d, m->search_domains) {
1170
1171 if (filter_route >= 0 &&
1172 d->route_only != !!filter_route)
1173 continue;
1174
1175 r = ordered_set_put(*domains, d->name);
1176 if (r == -EEXIST)
1177 continue;
1178 if (r < 0)
1179 return r;
1180 }
1181
1182 HASHMAP_FOREACH(l, m->links, i) {
1183
1184 LIST_FOREACH(domains, d, l->search_domains) {
1185
1186 if (filter_route >= 0 &&
1187 d->route_only != !!filter_route)
1188 continue;
1189
1190 r = ordered_set_put(*domains, d->name);
1191 if (r == -EEXIST)
1192 continue;
1193 if (r < 0)
1194 return r;
1195 }
1196 }
1197
1198 return 0;
1199 }
1200
1201 DnssecMode manager_get_dnssec_mode(Manager *m) {
1202 assert(m);
1203
1204 if (m->dnssec_mode != _DNSSEC_MODE_INVALID)
1205 return m->dnssec_mode;
1206
1207 return DNSSEC_NO;
1208 }
1209
1210 bool manager_dnssec_supported(Manager *m) {
1211 DnsServer *server;
1212 Iterator i;
1213 Link *l;
1214
1215 assert(m);
1216
1217 if (manager_get_dnssec_mode(m) == DNSSEC_NO)
1218 return false;
1219
1220 server = manager_get_dns_server(m);
1221 if (server && !dns_server_dnssec_supported(server))
1222 return false;
1223
1224 HASHMAP_FOREACH(l, m->links, i)
1225 if (!link_dnssec_supported(l))
1226 return false;
1227
1228 return true;
1229 }
1230
1231 void manager_dnssec_verdict(Manager *m, DnssecVerdict verdict, const DnsResourceKey *key) {
1232
1233 assert(verdict >= 0);
1234 assert(verdict < _DNSSEC_VERDICT_MAX);
1235
1236 if (log_get_max_level() >= LOG_DEBUG) {
1237 char s[DNS_RESOURCE_KEY_STRING_MAX];
1238
1239 log_debug("Found verdict for lookup %s: %s",
1240 dns_resource_key_to_string(key, s, sizeof s),
1241 dnssec_verdict_to_string(verdict));
1242 }
1243
1244 m->n_dnssec_verdict[verdict]++;
1245 }
1246
1247 bool manager_routable(Manager *m, int family) {
1248 Iterator i;
1249 Link *l;
1250
1251 assert(m);
1252
1253 /* Returns true if the host has at least one interface with a routable address of the specified type */
1254
1255 HASHMAP_FOREACH(l, m->links, i)
1256 if (link_relevant(l, family, false))
1257 return true;
1258
1259 return false;
1260 }
1261
1262 void manager_flush_caches(Manager *m) {
1263 DnsScope *scope;
1264
1265 assert(m);
1266
1267 LIST_FOREACH(scopes, scope, m->dns_scopes)
1268 dns_cache_flush(&scope->cache);
1269
1270 log_info("Flushed all caches.");
1271 }