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74b2466e LP |
1 | /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ |
2 | ||
3 | /*** | |
4 | This file is part of systemd. | |
5 | ||
6 | Copyright 2014 Lennart Poettering | |
7 | ||
8 | systemd is free software; you can redistribute it and/or modify it | |
9 | under the terms of the GNU Lesser General Public License as published by | |
10 | the Free Software Foundation; either version 2.1 of the License, or | |
11 | (at your option) any later version. | |
12 | ||
13 | systemd is distributed in the hope that it will be useful, but | |
14 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | Lesser General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU Lesser General Public License | |
19 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
20 | ***/ | |
21 | ||
b5efdb8a | 22 | #include "alloc-util.h" |
2a1037af | 23 | #include "dns-domain.h" |
b5efdb8a | 24 | #include "hostname-util.h" |
78c6a153 | 25 | #include "local-addresses.h" |
74b2466e | 26 | #include "resolved-dns-query.h" |
23b298bc | 27 | #include "string-util.h" |
74b2466e | 28 | |
0c903ae7 | 29 | /* How long to wait for the query in total */ |
74b2466e | 30 | #define QUERY_TIMEOUT_USEC (30 * USEC_PER_SEC) |
0c903ae7 | 31 | |
8ba9fd9c | 32 | #define CNAME_MAX 8 |
39762fdf | 33 | #define QUERIES_MAX 2048 |
45ec7efb | 34 | #define AUXILIARY_QUERIES_MAX 64 |
8ba9fd9c | 35 | |
801ad6a6 LP |
36 | static int dns_query_candidate_new(DnsQueryCandidate **ret, DnsQuery *q, DnsScope *s) { |
37 | DnsQueryCandidate *c; | |
74b2466e | 38 | |
801ad6a6 | 39 | assert(ret); |
faa133f3 | 40 | assert(q); |
801ad6a6 | 41 | assert(s); |
74b2466e | 42 | |
801ad6a6 LP |
43 | c = new0(DnsQueryCandidate, 1); |
44 | if (!c) | |
45 | return -ENOMEM; | |
46 | ||
47 | c->query = q; | |
48 | c->scope = s; | |
49 | ||
50 | LIST_PREPEND(candidates_by_query, q->candidates, c); | |
51 | LIST_PREPEND(candidates_by_scope, s->query_candidates, c); | |
52 | ||
53 | *ret = c; | |
54 | return 0; | |
55 | } | |
56 | ||
57 | static void dns_query_candidate_stop(DnsQueryCandidate *c) { | |
58 | DnsTransaction *t; | |
74b2466e | 59 | |
801ad6a6 LP |
60 | assert(c); |
61 | ||
62 | while ((t = set_steal_first(c->transactions))) { | |
547973de | 63 | set_remove(t->notify_query_candidates, c); |
ec2c5e43 | 64 | dns_transaction_gc(t); |
74b2466e | 65 | } |
74b2466e LP |
66 | } |
67 | ||
801ad6a6 LP |
68 | DnsQueryCandidate* dns_query_candidate_free(DnsQueryCandidate *c) { |
69 | ||
70 | if (!c) | |
71 | return NULL; | |
72 | ||
73 | dns_query_candidate_stop(c); | |
74 | ||
75 | set_free(c->transactions); | |
76 | dns_search_domain_unref(c->search_domain); | |
77 | ||
78 | if (c->query) | |
79 | LIST_REMOVE(candidates_by_query, c->query->candidates, c); | |
80 | ||
81 | if (c->scope) | |
82 | LIST_REMOVE(candidates_by_scope, c->scope->query_candidates, c); | |
83 | ||
84 | free(c); | |
85 | ||
86 | return NULL; | |
87 | } | |
88 | ||
89 | static int dns_query_candidate_next_search_domain(DnsQueryCandidate *c) { | |
801ad6a6 LP |
90 | DnsSearchDomain *next = NULL; |
91 | ||
92 | assert(c); | |
93 | ||
94 | if (c->search_domain && c->search_domain->linked) { | |
95 | next = c->search_domain->domains_next; | |
96 | ||
6627b7e2 LP |
97 | if (!next) /* We hit the end of the list */ |
98 | return 0; | |
801ad6a6 LP |
99 | |
100 | } else { | |
801ad6a6 LP |
101 | next = dns_scope_get_search_domains(c->scope); |
102 | ||
6627b7e2 | 103 | if (!next) /* OK, there's nothing. */ |
801ad6a6 LP |
104 | return 0; |
105 | } | |
106 | ||
107 | dns_search_domain_unref(c->search_domain); | |
108 | c->search_domain = dns_search_domain_ref(next); | |
6627b7e2 | 109 | |
801ad6a6 LP |
110 | return 1; |
111 | } | |
112 | ||
113 | static int dns_query_candidate_add_transaction(DnsQueryCandidate *c, DnsResourceKey *key) { | |
114 | DnsTransaction *t; | |
115 | int r; | |
116 | ||
117 | assert(c); | |
118 | assert(key); | |
119 | ||
801ad6a6 LP |
120 | t = dns_scope_find_transaction(c->scope, key, true); |
121 | if (!t) { | |
122 | r = dns_transaction_new(&t, c->scope, key); | |
123 | if (r < 0) | |
124 | return r; | |
547973de LP |
125 | } else { |
126 | if (set_contains(c->transactions, t)) | |
127 | return 0; | |
801ad6a6 LP |
128 | } |
129 | ||
547973de LP |
130 | r = set_ensure_allocated(&c->transactions, NULL); |
131 | if (r < 0) | |
132 | goto gc; | |
133 | ||
134 | r = set_ensure_allocated(&t->notify_query_candidates, NULL); | |
801ad6a6 LP |
135 | if (r < 0) |
136 | goto gc; | |
137 | ||
547973de | 138 | r = set_put(t->notify_query_candidates, c); |
801ad6a6 LP |
139 | if (r < 0) |
140 | goto gc; | |
141 | ||
142 | r = set_put(c->transactions, t); | |
143 | if (r < 0) { | |
547973de | 144 | (void) set_remove(t->notify_query_candidates, c); |
801ad6a6 LP |
145 | goto gc; |
146 | } | |
147 | ||
547973de | 148 | return 1; |
801ad6a6 LP |
149 | |
150 | gc: | |
151 | dns_transaction_gc(t); | |
152 | return r; | |
153 | } | |
154 | ||
155 | static int dns_query_candidate_go(DnsQueryCandidate *c) { | |
156 | DnsTransaction *t; | |
157 | Iterator i; | |
158 | int r; | |
159 | ||
160 | assert(c); | |
161 | ||
162 | /* Start the transactions that are not started yet */ | |
163 | SET_FOREACH(t, c->transactions, i) { | |
164 | if (t->state != DNS_TRANSACTION_NULL) | |
165 | continue; | |
166 | ||
167 | r = dns_transaction_go(t); | |
168 | if (r < 0) | |
169 | return r; | |
170 | } | |
171 | ||
172 | return 0; | |
173 | } | |
174 | ||
175 | static DnsTransactionState dns_query_candidate_state(DnsQueryCandidate *c) { | |
176 | DnsTransactionState state = DNS_TRANSACTION_NO_SERVERS; | |
177 | DnsTransaction *t; | |
178 | Iterator i; | |
179 | ||
180 | assert(c); | |
181 | ||
182 | if (c->error_code != 0) | |
183 | return DNS_TRANSACTION_RESOURCES; | |
184 | ||
185 | SET_FOREACH(t, c->transactions, i) { | |
186 | ||
187 | switch (t->state) { | |
188 | ||
5264131a LP |
189 | case DNS_TRANSACTION_NULL: |
190 | /* If there's a NULL transaction pending, then | |
191 | * this means not all transactions where | |
192 | * started yet, and we were called from within | |
193 | * the stackframe that is supposed to start | |
194 | * remaining transactions. In this case, | |
195 | * simply claim the candidate is pending. */ | |
196 | ||
801ad6a6 | 197 | case DNS_TRANSACTION_PENDING: |
547973de LP |
198 | case DNS_TRANSACTION_VALIDATING: |
199 | /* If there's one transaction currently in | |
200 | * VALIDATING state, then this means there's | |
201 | * also one in PENDING state, hence we can | |
202 | * return PENDING immediately. */ | |
203 | return DNS_TRANSACTION_PENDING; | |
801ad6a6 LP |
204 | |
205 | case DNS_TRANSACTION_SUCCESS: | |
206 | state = t->state; | |
207 | break; | |
208 | ||
209 | default: | |
210 | if (state != DNS_TRANSACTION_SUCCESS) | |
211 | state = t->state; | |
212 | ||
213 | break; | |
214 | } | |
215 | } | |
216 | ||
217 | return state; | |
218 | } | |
219 | ||
220 | static int dns_query_candidate_setup_transactions(DnsQueryCandidate *c) { | |
23b298bc | 221 | DnsQuestion *question; |
801ad6a6 LP |
222 | DnsResourceKey *key; |
223 | int n = 0, r; | |
224 | ||
225 | assert(c); | |
226 | ||
227 | dns_query_candidate_stop(c); | |
228 | ||
23b298bc LP |
229 | question = dns_query_question_for_protocol(c->query, c->scope->protocol); |
230 | ||
801ad6a6 | 231 | /* Create one transaction per question key */ |
23b298bc | 232 | DNS_QUESTION_FOREACH(key, question) { |
801ad6a6 LP |
233 | _cleanup_(dns_resource_key_unrefp) DnsResourceKey *new_key = NULL; |
234 | ||
235 | if (c->search_domain) { | |
236 | r = dns_resource_key_new_append_suffix(&new_key, key, c->search_domain->name); | |
237 | if (r < 0) | |
238 | goto fail; | |
239 | } | |
240 | ||
241 | r = dns_query_candidate_add_transaction(c, new_key ?: key); | |
242 | if (r < 0) | |
243 | goto fail; | |
244 | ||
245 | n++; | |
246 | } | |
247 | ||
248 | return n; | |
249 | ||
250 | fail: | |
251 | dns_query_candidate_stop(c); | |
252 | return r; | |
253 | } | |
254 | ||
547973de | 255 | void dns_query_candidate_notify(DnsQueryCandidate *c) { |
801ad6a6 LP |
256 | DnsTransactionState state; |
257 | int r; | |
258 | ||
259 | assert(c); | |
260 | ||
261 | state = dns_query_candidate_state(c); | |
262 | ||
547973de | 263 | if (DNS_TRANSACTION_IS_LIVE(state)) |
801ad6a6 LP |
264 | return; |
265 | ||
266 | if (state != DNS_TRANSACTION_SUCCESS && c->search_domain) { | |
267 | ||
268 | r = dns_query_candidate_next_search_domain(c); | |
269 | if (r < 0) | |
270 | goto fail; | |
271 | ||
272 | if (r > 0) { | |
273 | /* OK, there's another search domain to try, let's do so. */ | |
274 | ||
275 | r = dns_query_candidate_setup_transactions(c); | |
276 | if (r < 0) | |
277 | goto fail; | |
278 | ||
279 | if (r > 0) { | |
280 | /* New transactions where queued. Start them and wait */ | |
281 | ||
282 | r = dns_query_candidate_go(c); | |
283 | if (r < 0) | |
284 | goto fail; | |
285 | ||
286 | return; | |
287 | } | |
288 | } | |
289 | ||
290 | } | |
291 | ||
292 | dns_query_ready(c->query); | |
293 | return; | |
294 | ||
295 | fail: | |
296 | log_warning_errno(r, "Failed to follow search domains: %m"); | |
297 | c->error_code = r; | |
298 | dns_query_ready(c->query); | |
299 | } | |
300 | ||
301 | static void dns_query_stop(DnsQuery *q) { | |
302 | DnsQueryCandidate *c; | |
303 | ||
304 | assert(q); | |
305 | ||
306 | q->timeout_event_source = sd_event_source_unref(q->timeout_event_source); | |
307 | ||
308 | LIST_FOREACH(candidates_by_query, c, q->candidates) | |
309 | dns_query_candidate_stop(c); | |
310 | } | |
311 | ||
7820b320 LP |
312 | static void dns_query_free_candidates(DnsQuery *q) { |
313 | assert(q); | |
314 | ||
315 | while (q->candidates) | |
316 | dns_query_candidate_free(q->candidates); | |
317 | } | |
318 | ||
319 | static void dns_query_reset_answer(DnsQuery *q) { | |
320 | assert(q); | |
321 | ||
322 | q->answer = dns_answer_unref(q->answer); | |
323 | q->answer_rcode = 0; | |
324 | q->answer_dnssec_result = _DNSSEC_RESULT_INVALID; | |
325 | q->answer_authenticated = false; | |
326 | q->answer_protocol = _DNS_PROTOCOL_INVALID; | |
327 | q->answer_family = AF_UNSPEC; | |
328 | q->answer_search_domain = dns_search_domain_unref(q->answer_search_domain); | |
329 | } | |
330 | ||
74b2466e | 331 | DnsQuery *dns_query_free(DnsQuery *q) { |
74b2466e LP |
332 | if (!q) |
333 | return NULL; | |
334 | ||
45ec7efb LP |
335 | while (q->auxiliary_queries) |
336 | dns_query_free(q->auxiliary_queries); | |
337 | ||
338 | if (q->auxiliary_for) { | |
339 | assert(q->auxiliary_for->n_auxiliary_queries > 0); | |
340 | q->auxiliary_for->n_auxiliary_queries--; | |
341 | LIST_REMOVE(auxiliary_queries, q->auxiliary_for->auxiliary_queries, q); | |
342 | } | |
343 | ||
7820b320 | 344 | dns_query_free_candidates(q); |
322345fd | 345 | |
23b298bc LP |
346 | dns_question_unref(q->question_idna); |
347 | dns_question_unref(q->question_utf8); | |
7820b320 LP |
348 | |
349 | dns_query_reset_answer(q); | |
322345fd | 350 | |
ec2c5e43 | 351 | sd_bus_message_unref(q->request); |
82bd6ddd | 352 | sd_bus_track_unref(q->bus_track); |
74b2466e | 353 | |
23b298bc LP |
354 | free(q->request_address_string); |
355 | ||
39762fdf | 356 | if (q->manager) { |
74b2466e | 357 | LIST_REMOVE(queries, q->manager->dns_queries, q); |
39762fdf LP |
358 | q->manager->n_dns_queries--; |
359 | } | |
74b2466e | 360 | |
74b2466e LP |
361 | free(q); |
362 | ||
363 | return NULL; | |
364 | } | |
365 | ||
23b298bc LP |
366 | int dns_query_new( |
367 | Manager *m, | |
368 | DnsQuery **ret, | |
369 | DnsQuestion *question_utf8, | |
370 | DnsQuestion *question_idna, | |
371 | int ifindex, uint64_t flags) { | |
372 | ||
74b2466e | 373 | _cleanup_(dns_query_freep) DnsQuery *q = NULL; |
23b298bc LP |
374 | DnsResourceKey *key; |
375 | bool good = false; | |
faa133f3 | 376 | int r; |
74b2466e LP |
377 | |
378 | assert(m); | |
379 | ||
23b298bc LP |
380 | if (dns_question_size(question_utf8) > 0) { |
381 | r = dns_question_is_valid_for_query(question_utf8); | |
382 | if (r < 0) | |
383 | return r; | |
384 | if (r == 0) | |
385 | return -EINVAL; | |
386 | ||
387 | good = true; | |
388 | } | |
389 | ||
390 | /* If the IDNA and UTF8 questions are the same, merge their references */ | |
391 | r = dns_question_is_equal(question_idna, question_utf8); | |
faa133f3 LP |
392 | if (r < 0) |
393 | return r; | |
23b298bc LP |
394 | if (r > 0) |
395 | question_idna = question_utf8; | |
396 | else { | |
397 | if (dns_question_size(question_idna) > 0) { | |
398 | r = dns_question_is_valid_for_query(question_idna); | |
399 | if (r < 0) | |
400 | return r; | |
401 | if (r == 0) | |
402 | return -EINVAL; | |
403 | ||
404 | good = true; | |
405 | } | |
406 | } | |
407 | ||
408 | if (!good) /* don't allow empty queries */ | |
409 | return -EINVAL; | |
74b2466e | 410 | |
39762fdf LP |
411 | if (m->n_dns_queries >= QUERIES_MAX) |
412 | return -EBUSY; | |
413 | ||
74b2466e LP |
414 | q = new0(DnsQuery, 1); |
415 | if (!q) | |
416 | return -ENOMEM; | |
417 | ||
23b298bc LP |
418 | q->question_utf8 = dns_question_ref(question_utf8); |
419 | q->question_idna = dns_question_ref(question_idna); | |
51323288 LP |
420 | q->ifindex = ifindex; |
421 | q->flags = flags; | |
7820b320 | 422 | q->answer_dnssec_result = _DNSSEC_RESULT_INVALID; |
801ad6a6 | 423 | q->answer_protocol = _DNS_PROTOCOL_INVALID; |
7820b320 | 424 | q->answer_family = AF_UNSPEC; |
322345fd | 425 | |
23b298bc LP |
426 | /* First dump UTF8 question */ |
427 | DNS_QUESTION_FOREACH(key, question_utf8) { | |
428 | _cleanup_free_ char *p = NULL; | |
e4501ed4 | 429 | |
23b298bc | 430 | r = dns_resource_key_to_string(key, &p); |
e4501ed4 LP |
431 | if (r < 0) |
432 | return r; | |
433 | ||
23b298bc LP |
434 | log_debug("Looking up RR for %s.", strstrip(p)); |
435 | } | |
436 | ||
437 | /* And then dump the IDNA question, but only what hasn't been dumped already through the UTF8 question. */ | |
438 | DNS_QUESTION_FOREACH(key, question_idna) { | |
439 | _cleanup_free_ char *p = NULL; | |
440 | ||
441 | r = dns_question_contains(question_utf8, key); | |
442 | if (r < 0) | |
443 | return r; | |
444 | if (r > 0) | |
445 | continue; | |
446 | ||
447 | r = dns_resource_key_to_string(key, &p); | |
448 | if (r < 0) | |
449 | return r; | |
450 | ||
451 | log_debug("Looking up IDNA RR for %s.", strstrip(p)); | |
74b2466e LP |
452 | } |
453 | ||
454 | LIST_PREPEND(queries, m->dns_queries, q); | |
39762fdf | 455 | m->n_dns_queries++; |
74b2466e LP |
456 | q->manager = m; |
457 | ||
8ba9fd9c LP |
458 | if (ret) |
459 | *ret = q; | |
460 | q = NULL; | |
461 | ||
462 | return 0; | |
463 | } | |
464 | ||
45ec7efb LP |
465 | int dns_query_make_auxiliary(DnsQuery *q, DnsQuery *auxiliary_for) { |
466 | assert(q); | |
467 | assert(auxiliary_for); | |
468 | ||
469 | /* Ensure that that the query is not auxiliary yet, and | |
470 | * nothing else is auxiliary to it either */ | |
471 | assert(!q->auxiliary_for); | |
472 | assert(!q->auxiliary_queries); | |
473 | ||
474 | /* Ensure that the unit we shall be made auxiliary for isn't | |
475 | * auxiliary itself */ | |
476 | assert(!auxiliary_for->auxiliary_for); | |
477 | ||
478 | if (auxiliary_for->n_auxiliary_queries >= AUXILIARY_QUERIES_MAX) | |
479 | return -EAGAIN; | |
480 | ||
481 | LIST_PREPEND(auxiliary_queries, auxiliary_for->auxiliary_queries, q); | |
482 | q->auxiliary_for = auxiliary_for; | |
483 | ||
484 | auxiliary_for->n_auxiliary_queries++; | |
485 | return 0; | |
486 | } | |
487 | ||
ec2c5e43 | 488 | static void dns_query_complete(DnsQuery *q, DnsTransactionState state) { |
8ba9fd9c | 489 | assert(q); |
547973de LP |
490 | assert(!DNS_TRANSACTION_IS_LIVE(state)); |
491 | assert(DNS_TRANSACTION_IS_LIVE(q->state)); | |
8ba9fd9c | 492 | |
322345fd LP |
493 | /* Note that this call might invalidate the query. Callers |
494 | * should hence not attempt to access the query or transaction | |
495 | * after calling this function. */ | |
8ba9fd9c | 496 | |
8ba9fd9c LP |
497 | q->state = state; |
498 | ||
322345fd LP |
499 | dns_query_stop(q); |
500 | if (q->complete) | |
501 | q->complete(q); | |
8ba9fd9c LP |
502 | } |
503 | ||
504 | static int on_query_timeout(sd_event_source *s, usec_t usec, void *userdata) { | |
505 | DnsQuery *q = userdata; | |
506 | ||
507 | assert(s); | |
508 | assert(q); | |
509 | ||
ec2c5e43 | 510 | dns_query_complete(q, DNS_TRANSACTION_TIMEOUT); |
8ba9fd9c LP |
511 | return 0; |
512 | } | |
513 | ||
801ad6a6 LP |
514 | static int dns_query_add_candidate(DnsQuery *q, DnsScope *s) { |
515 | DnsQueryCandidate *c; | |
faa133f3 LP |
516 | int r; |
517 | ||
518 | assert(q); | |
ec2c5e43 | 519 | assert(s); |
faa133f3 | 520 | |
801ad6a6 | 521 | r = dns_query_candidate_new(&c, q, s); |
faa133f3 LP |
522 | if (r < 0) |
523 | return r; | |
524 | ||
801ad6a6 | 525 | /* If this a single-label domain on DNS, we might append a suitable search domain first. */ |
22f711bb | 526 | if ((q->flags & SD_RESOLVED_NO_SEARCH) == 0) { |
23b298bc | 527 | r = dns_scope_name_needs_search_domain(s, dns_question_first_name(q->question_idna)); |
22f711bb | 528 | if (r < 0) |
801ad6a6 | 529 | goto fail; |
22f711bb LP |
530 | if (r > 0) { |
531 | /* OK, we need a search domain now. Let's find one for this scope */ | |
532 | ||
533 | r = dns_query_candidate_next_search_domain(c); | |
534 | if (r <= 0) /* if there's no search domain, then we won't add any transaction. */ | |
535 | goto fail; | |
536 | } | |
faa133f3 LP |
537 | } |
538 | ||
801ad6a6 LP |
539 | r = dns_query_candidate_setup_transactions(c); |
540 | if (r < 0) | |
541 | goto fail; | |
542 | ||
faa133f3 LP |
543 | return 0; |
544 | ||
801ad6a6 LP |
545 | fail: |
546 | dns_query_candidate_free(c); | |
faa133f3 LP |
547 | return r; |
548 | } | |
549 | ||
2a1037af LP |
550 | static int SYNTHESIZE_IFINDEX(int ifindex) { |
551 | ||
78c6a153 LP |
552 | /* When the caller asked for resolving on a specific |
553 | * interface, we synthesize the answer for that | |
554 | * interface. However, if nothing specific was claimed and we | |
555 | * only return localhost RRs, we synthesize the answer for | |
2a1037af LP |
556 | * localhost. */ |
557 | ||
558 | if (ifindex > 0) | |
559 | return ifindex; | |
560 | ||
561 | return LOOPBACK_IFINDEX; | |
562 | } | |
563 | ||
564 | static int SYNTHESIZE_FAMILY(uint64_t flags) { | |
565 | ||
566 | /* Picks an address family depending on set flags. This is | |
567 | * purely for synthesized answers, where the family we return | |
568 | * for the reply should match what was requested in the | |
569 | * question, even though we are synthesizing the answer | |
570 | * here. */ | |
571 | ||
572 | if (!(flags & SD_RESOLVED_DNS)) { | |
573 | if (flags & SD_RESOLVED_LLMNR_IPV4) | |
574 | return AF_INET; | |
575 | if (flags & SD_RESOLVED_LLMNR_IPV6) | |
576 | return AF_INET6; | |
577 | } | |
578 | ||
579 | return AF_UNSPEC; | |
580 | } | |
581 | ||
582 | static DnsProtocol SYNTHESIZE_PROTOCOL(uint64_t flags) { | |
583 | ||
584 | /* Similar as SYNTHESIZE_FAMILY() but does this for the | |
585 | * protocol. If resolving via DNS was requested, we claim it | |
586 | * was DNS. Similar, if nothing specific was | |
587 | * requested. However, if only resolving via LLMNR was | |
588 | * requested we return that. */ | |
589 | ||
590 | if (flags & SD_RESOLVED_DNS) | |
591 | return DNS_PROTOCOL_DNS; | |
592 | if (flags & SD_RESOLVED_LLMNR) | |
593 | return DNS_PROTOCOL_LLMNR; | |
594 | ||
595 | return DNS_PROTOCOL_DNS; | |
596 | } | |
597 | ||
23b298bc | 598 | static int synthesize_localhost_rr(DnsQuery *q, const DnsResourceKey *key, DnsAnswer **answer) { |
78c6a153 LP |
599 | int r; |
600 | ||
601 | assert(q); | |
602 | assert(key); | |
603 | assert(answer); | |
604 | ||
605 | r = dns_answer_reserve(answer, 2); | |
606 | if (r < 0) | |
607 | return r; | |
608 | ||
609 | if (IN_SET(key->type, DNS_TYPE_A, DNS_TYPE_ANY)) { | |
610 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; | |
611 | ||
612 | rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_A, DNS_RESOURCE_KEY_NAME(key)); | |
613 | if (!rr) | |
614 | return -ENOMEM; | |
615 | ||
616 | rr->a.in_addr.s_addr = htobe32(INADDR_LOOPBACK); | |
617 | ||
105e1512 | 618 | r = dns_answer_add(*answer, rr, SYNTHESIZE_IFINDEX(q->ifindex), DNS_ANSWER_AUTHENTICATED); |
78c6a153 LP |
619 | if (r < 0) |
620 | return r; | |
621 | } | |
622 | ||
623 | if (IN_SET(key->type, DNS_TYPE_AAAA, DNS_TYPE_ANY)) { | |
624 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; | |
625 | ||
626 | rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_AAAA, DNS_RESOURCE_KEY_NAME(key)); | |
627 | if (!rr) | |
628 | return -ENOMEM; | |
629 | ||
630 | rr->aaaa.in6_addr = in6addr_loopback; | |
631 | ||
105e1512 | 632 | r = dns_answer_add(*answer, rr, SYNTHESIZE_IFINDEX(q->ifindex), DNS_ANSWER_AUTHENTICATED); |
78c6a153 LP |
633 | if (r < 0) |
634 | return r; | |
635 | } | |
636 | ||
637 | return 0; | |
638 | } | |
639 | ||
105e1512 | 640 | static int answer_add_ptr(DnsAnswer **answer, const char *from, const char *to, int ifindex, DnsAnswerFlags flags) { |
78c6a153 LP |
641 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; |
642 | ||
643 | rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_PTR, from); | |
644 | if (!rr) | |
645 | return -ENOMEM; | |
646 | ||
647 | rr->ptr.name = strdup(to); | |
648 | if (!rr->ptr.name) | |
649 | return -ENOMEM; | |
650 | ||
105e1512 | 651 | return dns_answer_add(*answer, rr, ifindex, flags); |
78c6a153 LP |
652 | } |
653 | ||
23b298bc | 654 | static int synthesize_localhost_ptr(DnsQuery *q, const DnsResourceKey *key, DnsAnswer **answer) { |
78c6a153 LP |
655 | int r; |
656 | ||
657 | assert(q); | |
658 | assert(key); | |
659 | assert(answer); | |
660 | ||
78c6a153 | 661 | if (IN_SET(key->type, DNS_TYPE_PTR, DNS_TYPE_ANY)) { |
105e1512 LP |
662 | r = dns_answer_reserve(answer, 1); |
663 | if (r < 0) | |
664 | return r; | |
665 | ||
666 | r = answer_add_ptr(answer, DNS_RESOURCE_KEY_NAME(key), "localhost", SYNTHESIZE_IFINDEX(q->ifindex), DNS_ANSWER_AUTHENTICATED); | |
78c6a153 LP |
667 | if (r < 0) |
668 | return r; | |
669 | } | |
670 | ||
671 | return 0; | |
672 | } | |
673 | ||
674 | static int answer_add_addresses_rr( | |
675 | DnsAnswer **answer, | |
676 | const char *name, | |
677 | struct local_address *addresses, | |
678 | unsigned n_addresses) { | |
679 | ||
680 | unsigned j; | |
681 | int r; | |
682 | ||
683 | assert(answer); | |
684 | assert(name); | |
685 | ||
686 | r = dns_answer_reserve(answer, n_addresses); | |
687 | if (r < 0) | |
688 | return r; | |
689 | ||
690 | for (j = 0; j < n_addresses; j++) { | |
691 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; | |
692 | ||
693 | r = dns_resource_record_new_address(&rr, addresses[j].family, &addresses[j].address, name); | |
694 | if (r < 0) | |
695 | return r; | |
696 | ||
105e1512 | 697 | r = dns_answer_add(*answer, rr, addresses[j].ifindex, DNS_ANSWER_AUTHENTICATED); |
78c6a153 LP |
698 | if (r < 0) |
699 | return r; | |
700 | } | |
701 | ||
702 | return 0; | |
703 | } | |
704 | ||
705 | static int answer_add_addresses_ptr( | |
706 | DnsAnswer **answer, | |
707 | const char *name, | |
708 | struct local_address *addresses, | |
709 | unsigned n_addresses, | |
710 | int af, const union in_addr_union *match) { | |
711 | ||
712 | unsigned j; | |
713 | int r; | |
714 | ||
715 | assert(answer); | |
716 | assert(name); | |
717 | ||
718 | for (j = 0; j < n_addresses; j++) { | |
719 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; | |
720 | ||
721 | if (af != AF_UNSPEC) { | |
722 | ||
723 | if (addresses[j].family != af) | |
724 | continue; | |
725 | ||
726 | if (match && !in_addr_equal(af, match, &addresses[j].address)) | |
727 | continue; | |
728 | } | |
729 | ||
730 | r = dns_answer_reserve(answer, 1); | |
731 | if (r < 0) | |
732 | return r; | |
733 | ||
734 | r = dns_resource_record_new_reverse(&rr, addresses[j].family, &addresses[j].address, name); | |
735 | if (r < 0) | |
736 | return r; | |
737 | ||
105e1512 | 738 | r = dns_answer_add(*answer, rr, addresses[j].ifindex, DNS_ANSWER_AUTHENTICATED); |
78c6a153 LP |
739 | if (r < 0) |
740 | return r; | |
741 | } | |
742 | ||
743 | return 0; | |
744 | } | |
745 | ||
23b298bc | 746 | static int synthesize_system_hostname_rr(DnsQuery *q, const DnsResourceKey *key, DnsAnswer **answer) { |
78c6a153 LP |
747 | _cleanup_free_ struct local_address *addresses = NULL; |
748 | int n = 0, af; | |
749 | ||
750 | assert(q); | |
751 | assert(key); | |
752 | assert(answer); | |
753 | ||
754 | af = dns_type_to_af(key->type); | |
755 | if (af >= 0) { | |
756 | n = local_addresses(q->manager->rtnl, q->ifindex, af, &addresses); | |
757 | if (n < 0) | |
758 | return n; | |
759 | ||
760 | if (n == 0) { | |
761 | struct local_address buffer[2]; | |
762 | ||
763 | /* If we have no local addresses then use ::1 | |
764 | * and 127.0.0.2 as local ones. */ | |
765 | ||
766 | if (af == AF_INET || af == AF_UNSPEC) | |
767 | buffer[n++] = (struct local_address) { | |
768 | .family = AF_INET, | |
769 | .ifindex = SYNTHESIZE_IFINDEX(q->ifindex), | |
770 | .address.in.s_addr = htobe32(0x7F000002), | |
771 | }; | |
772 | ||
773 | if (af == AF_INET6 || af == AF_UNSPEC) | |
774 | buffer[n++] = (struct local_address) { | |
775 | .family = AF_INET6, | |
776 | .ifindex = SYNTHESIZE_IFINDEX(q->ifindex), | |
777 | .address.in6 = in6addr_loopback, | |
778 | }; | |
779 | ||
780 | return answer_add_addresses_rr(answer, DNS_RESOURCE_KEY_NAME(key), buffer, n); | |
781 | } | |
782 | } | |
783 | ||
784 | return answer_add_addresses_rr(answer, DNS_RESOURCE_KEY_NAME(key), addresses, n); | |
785 | } | |
786 | ||
787 | static int synthesize_system_hostname_ptr(DnsQuery *q, int af, const union in_addr_union *address, DnsAnswer **answer) { | |
788 | _cleanup_free_ struct local_address *addresses = NULL; | |
789 | int n, r; | |
790 | ||
791 | assert(q); | |
792 | assert(address); | |
793 | assert(answer); | |
794 | ||
795 | if (af == AF_INET && address->in.s_addr == htobe32(0x7F000002)) { | |
796 | ||
797 | /* Always map the IPv4 address 127.0.0.2 to the local | |
798 | * hostname, in addition to "localhost": */ | |
799 | ||
800 | r = dns_answer_reserve(answer, 3); | |
801 | if (r < 0) | |
802 | return r; | |
803 | ||
105e1512 | 804 | r = answer_add_ptr(answer, "2.0.0.127.in-addr.arpa", q->manager->llmnr_hostname, SYNTHESIZE_IFINDEX(q->ifindex), DNS_ANSWER_AUTHENTICATED); |
78c6a153 LP |
805 | if (r < 0) |
806 | return r; | |
807 | ||
105e1512 | 808 | r = answer_add_ptr(answer, "2.0.0.127.in-addr.arpa", q->manager->mdns_hostname, SYNTHESIZE_IFINDEX(q->ifindex), DNS_ANSWER_AUTHENTICATED); |
78c6a153 LP |
809 | if (r < 0) |
810 | return r; | |
811 | ||
105e1512 | 812 | r = answer_add_ptr(answer, "2.0.0.127.in-addr.arpa", "localhost", SYNTHESIZE_IFINDEX(q->ifindex), DNS_ANSWER_AUTHENTICATED); |
78c6a153 LP |
813 | if (r < 0) |
814 | return r; | |
815 | ||
816 | return 0; | |
817 | } | |
818 | ||
819 | n = local_addresses(q->manager->rtnl, q->ifindex, af, &addresses); | |
820 | if (n < 0) | |
821 | return n; | |
822 | ||
823 | r = answer_add_addresses_ptr(answer, q->manager->llmnr_hostname, addresses, n, af, address); | |
824 | if (r < 0) | |
825 | return r; | |
826 | ||
827 | return answer_add_addresses_ptr(answer, q->manager->mdns_hostname, addresses, n, af, address); | |
828 | } | |
829 | ||
23b298bc | 830 | static int synthesize_gateway_rr(DnsQuery *q, const DnsResourceKey *key, DnsAnswer **answer) { |
78c6a153 LP |
831 | _cleanup_free_ struct local_address *addresses = NULL; |
832 | int n = 0, af; | |
833 | ||
834 | assert(q); | |
835 | assert(key); | |
836 | assert(answer); | |
837 | ||
838 | af = dns_type_to_af(key->type); | |
839 | if (af >= 0) { | |
840 | n = local_gateways(q->manager->rtnl, q->ifindex, af, &addresses); | |
841 | if (n < 0) | |
842 | return n; | |
843 | } | |
844 | ||
845 | return answer_add_addresses_rr(answer, DNS_RESOURCE_KEY_NAME(key), addresses, n); | |
846 | } | |
847 | ||
848 | static int synthesize_gateway_ptr(DnsQuery *q, int af, const union in_addr_union *address, DnsAnswer **answer) { | |
849 | _cleanup_free_ struct local_address *addresses = NULL; | |
850 | int n; | |
851 | ||
852 | assert(q); | |
853 | assert(address); | |
854 | assert(answer); | |
855 | ||
856 | n = local_gateways(q->manager->rtnl, q->ifindex, af, &addresses); | |
857 | if (n < 0) | |
858 | return n; | |
859 | ||
860 | return answer_add_addresses_ptr(answer, "gateway", addresses, n, af, address); | |
861 | } | |
862 | ||
863 | static int dns_query_synthesize_reply(DnsQuery *q, DnsTransactionState *state) { | |
2a1037af | 864 | _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; |
23b298bc | 865 | DnsResourceKey *key; |
2a1037af LP |
866 | int r; |
867 | ||
868 | assert(q); | |
869 | assert(state); | |
870 | ||
871 | /* Tries to synthesize localhost RR replies where appropriate */ | |
872 | ||
873 | if (!IN_SET(*state, | |
3bbdc31d | 874 | DNS_TRANSACTION_RCODE_FAILURE, |
2a1037af LP |
875 | DNS_TRANSACTION_NO_SERVERS, |
876 | DNS_TRANSACTION_TIMEOUT, | |
edbcc1fd LP |
877 | DNS_TRANSACTION_ATTEMPTS_MAX_REACHED, |
878 | DNS_TRANSACTION_NETWORK_DOWN)) | |
78c6a153 | 879 | return 0; |
2a1037af | 880 | |
23b298bc | 881 | DNS_QUESTION_FOREACH(key, q->question_utf8) { |
78c6a153 | 882 | union in_addr_union address; |
2a1037af | 883 | const char *name; |
78c6a153 | 884 | int af; |
2a1037af | 885 | |
23b298bc LP |
886 | if (key->class != DNS_CLASS_IN && |
887 | key->class != DNS_CLASS_ANY) | |
2a1037af LP |
888 | continue; |
889 | ||
23b298bc | 890 | name = DNS_RESOURCE_KEY_NAME(key); |
2a1037af LP |
891 | |
892 | if (is_localhost(name)) { | |
893 | ||
23b298bc | 894 | r = synthesize_localhost_rr(q, key, &answer); |
78c6a153 LP |
895 | if (r < 0) |
896 | return log_error_errno(r, "Failed to synthesize localhost RRs: %m"); | |
2a1037af | 897 | |
78c6a153 | 898 | } else if (manager_is_own_hostname(q->manager, name)) { |
2a1037af | 899 | |
23b298bc | 900 | r = synthesize_system_hostname_rr(q, key, &answer); |
78c6a153 LP |
901 | if (r < 0) |
902 | return log_error_errno(r, "Failed to synthesize system hostname RRs: %m"); | |
2a1037af | 903 | |
78c6a153 | 904 | } else if (is_gateway_hostname(name)) { |
2a1037af | 905 | |
23b298bc | 906 | r = synthesize_gateway_rr(q, key, &answer); |
78c6a153 LP |
907 | if (r < 0) |
908 | return log_error_errno(r, "Failed to synthesize gateway RRs: %m"); | |
2a1037af | 909 | |
78c6a153 LP |
910 | } else if ((dns_name_endswith(name, "127.in-addr.arpa") > 0 && dns_name_equal(name, "2.0.0.127.in-addr.arpa") == 0) || |
911 | dns_name_equal(name, "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa") > 0) { | |
2a1037af | 912 | |
23b298bc | 913 | r = synthesize_localhost_ptr(q, key, &answer); |
78c6a153 LP |
914 | if (r < 0) |
915 | return log_error_errno(r, "Failed to synthesize localhost PTR RRs: %m"); | |
2a1037af | 916 | |
78c6a153 | 917 | } else if (dns_name_address(name, &af, &address) > 0) { |
2a1037af | 918 | |
78c6a153 LP |
919 | r = synthesize_system_hostname_ptr(q, af, &address, &answer); |
920 | if (r < 0) | |
921 | return log_error_errno(r, "Failed to synthesize system hostname PTR RR: %m"); | |
2a1037af | 922 | |
78c6a153 LP |
923 | r = synthesize_gateway_ptr(q, af, &address, &answer); |
924 | if (r < 0) | |
925 | return log_error_errno(r, "Failed to synthesize gateway hostname PTR RR: %m"); | |
2a1037af LP |
926 | } |
927 | } | |
928 | ||
929 | if (!answer) | |
78c6a153 | 930 | return 0; |
2a1037af LP |
931 | |
932 | dns_answer_unref(q->answer); | |
933 | q->answer = answer; | |
934 | answer = NULL; | |
935 | ||
2a1037af | 936 | q->answer_rcode = DNS_RCODE_SUCCESS; |
801ad6a6 LP |
937 | q->answer_protocol = SYNTHESIZE_PROTOCOL(q->flags); |
938 | q->answer_family = SYNTHESIZE_FAMILY(q->flags); | |
2a1037af LP |
939 | |
940 | *state = DNS_TRANSACTION_SUCCESS; | |
78c6a153 LP |
941 | |
942 | return 1; | |
2a1037af LP |
943 | } |
944 | ||
322345fd | 945 | int dns_query_go(DnsQuery *q) { |
8ba9fd9c LP |
946 | DnsScopeMatch found = DNS_SCOPE_NO; |
947 | DnsScope *s, *first = NULL; | |
801ad6a6 | 948 | DnsQueryCandidate *c; |
8ba9fd9c LP |
949 | int r; |
950 | ||
951 | assert(q); | |
952 | ||
ec2c5e43 | 953 | if (q->state != DNS_TRANSACTION_NULL) |
8ba9fd9c LP |
954 | return 0; |
955 | ||
8ba9fd9c | 956 | LIST_FOREACH(scopes, s, q->manager->dns_scopes) { |
74b2466e | 957 | DnsScopeMatch match; |
23b298bc LP |
958 | const char *name; |
959 | ||
960 | name = dns_question_first_name(dns_query_question_for_protocol(q, s->protocol)); | |
961 | if (!name) | |
962 | continue; | |
74b2466e | 963 | |
51323288 | 964 | match = dns_scope_good_domain(s, q->ifindex, q->flags, name); |
74b2466e LP |
965 | if (match < 0) |
966 | return match; | |
967 | ||
968 | if (match == DNS_SCOPE_NO) | |
969 | continue; | |
970 | ||
971 | found = match; | |
972 | ||
973 | if (match == DNS_SCOPE_YES) { | |
974 | first = s; | |
975 | break; | |
976 | } else { | |
977 | assert(match == DNS_SCOPE_MAYBE); | |
978 | ||
979 | if (!first) | |
980 | first = s; | |
981 | } | |
982 | } | |
983 | ||
2a1037af LP |
984 | if (found == DNS_SCOPE_NO) { |
985 | DnsTransactionState state = DNS_TRANSACTION_NO_SERVERS; | |
986 | ||
987 | dns_query_synthesize_reply(q, &state); | |
d634711b LP |
988 | dns_query_complete(q, state); |
989 | return 1; | |
2a1037af | 990 | } |
74b2466e | 991 | |
801ad6a6 | 992 | r = dns_query_add_candidate(q, first); |
74b2466e | 993 | if (r < 0) |
ec2c5e43 | 994 | goto fail; |
74b2466e | 995 | |
74b2466e LP |
996 | LIST_FOREACH(scopes, s, first->scopes_next) { |
997 | DnsScopeMatch match; | |
23b298bc LP |
998 | const char *name; |
999 | ||
1000 | name = dns_question_first_name(dns_query_question_for_protocol(q, s->protocol)); | |
1001 | if (!name) | |
1002 | continue; | |
74b2466e | 1003 | |
51323288 | 1004 | match = dns_scope_good_domain(s, q->ifindex, q->flags, name); |
74b2466e | 1005 | if (match < 0) |
ec2c5e43 | 1006 | goto fail; |
74b2466e LP |
1007 | |
1008 | if (match != found) | |
1009 | continue; | |
1010 | ||
801ad6a6 | 1011 | r = dns_query_add_candidate(q, s); |
74b2466e | 1012 | if (r < 0) |
ec2c5e43 | 1013 | goto fail; |
74b2466e LP |
1014 | } |
1015 | ||
faa133f3 | 1016 | q->answer = dns_answer_unref(q->answer); |
faa133f3 | 1017 | q->answer_rcode = 0; |
51323288 LP |
1018 | q->answer_family = AF_UNSPEC; |
1019 | q->answer_protocol = _DNS_PROTOCOL_INVALID; | |
74b2466e | 1020 | |
9a015429 LP |
1021 | r = sd_event_add_time( |
1022 | q->manager->event, | |
1023 | &q->timeout_event_source, | |
1024 | clock_boottime_or_monotonic(), | |
1025 | now(clock_boottime_or_monotonic()) + QUERY_TIMEOUT_USEC, 0, | |
1026 | on_query_timeout, q); | |
74b2466e LP |
1027 | if (r < 0) |
1028 | goto fail; | |
1029 | ||
aa4a9deb LP |
1030 | (void) sd_event_source_set_description(q->timeout_event_source, "query-timeout"); |
1031 | ||
ec2c5e43 | 1032 | q->state = DNS_TRANSACTION_PENDING; |
faa133f3 | 1033 | q->block_ready++; |
74b2466e | 1034 | |
801ad6a6 LP |
1035 | /* Start the transactions */ |
1036 | LIST_FOREACH(candidates_by_query, c, q->candidates) { | |
1037 | r = dns_query_candidate_go(c); | |
1038 | if (r < 0) { | |
1039 | q->block_ready--; | |
ec2c5e43 | 1040 | goto fail; |
801ad6a6 | 1041 | } |
74b2466e LP |
1042 | } |
1043 | ||
faa133f3 LP |
1044 | q->block_ready--; |
1045 | dns_query_ready(q); | |
322345fd | 1046 | |
8ba9fd9c | 1047 | return 1; |
74b2466e LP |
1048 | |
1049 | fail: | |
8ba9fd9c | 1050 | dns_query_stop(q); |
74b2466e LP |
1051 | return r; |
1052 | } | |
1053 | ||
801ad6a6 | 1054 | static void dns_query_accept(DnsQuery *q, DnsQueryCandidate *c) { |
ec2c5e43 | 1055 | DnsTransactionState state = DNS_TRANSACTION_NO_SERVERS; |
547973de | 1056 | bool has_authenticated = false, has_non_authenticated = false; |
019036a4 | 1057 | DnssecResult dnssec_result_authenticated = _DNSSEC_RESULT_INVALID, dnssec_result_non_authenticated = _DNSSEC_RESULT_INVALID; |
801ad6a6 | 1058 | DnsTransaction *t; |
faa133f3 | 1059 | Iterator i; |
547973de | 1060 | int r; |
74b2466e LP |
1061 | |
1062 | assert(q); | |
1063 | ||
801ad6a6 LP |
1064 | if (!c) { |
1065 | dns_query_synthesize_reply(q, &state); | |
1066 | dns_query_complete(q, state); | |
74b2466e | 1067 | return; |
801ad6a6 | 1068 | } |
74b2466e | 1069 | |
801ad6a6 | 1070 | SET_FOREACH(t, c->transactions, i) { |
74b2466e | 1071 | |
801ad6a6 | 1072 | switch (t->state) { |
934e9b10 | 1073 | |
801ad6a6 LP |
1074 | case DNS_TRANSACTION_SUCCESS: { |
1075 | /* We found a successfuly reply, merge it into the answer */ | |
547973de LP |
1076 | r = dns_answer_extend(&q->answer, t->answer); |
1077 | if (r < 0) { | |
801ad6a6 LP |
1078 | dns_query_complete(q, DNS_TRANSACTION_RESOURCES); |
1079 | return; | |
1080 | } | |
019036a4 | 1081 | |
ae6a4bbf | 1082 | q->answer_rcode = t->answer_rcode; |
801ad6a6 | 1083 | |
019036a4 | 1084 | if (t->answer_authenticated) { |
931851e8 | 1085 | has_authenticated = true; |
019036a4 LP |
1086 | dnssec_result_authenticated = t->answer_dnssec_result; |
1087 | } else { | |
931851e8 | 1088 | has_non_authenticated = true; |
019036a4 LP |
1089 | dnssec_result_non_authenticated = t->answer_dnssec_result; |
1090 | } | |
931851e8 | 1091 | |
801ad6a6 LP |
1092 | state = DNS_TRANSACTION_SUCCESS; |
1093 | break; | |
1094 | } | |
1095 | ||
801ad6a6 | 1096 | case DNS_TRANSACTION_NULL: |
547973de LP |
1097 | case DNS_TRANSACTION_PENDING: |
1098 | case DNS_TRANSACTION_VALIDATING: | |
801ad6a6 LP |
1099 | case DNS_TRANSACTION_ABORTED: |
1100 | /* Ignore transactions that didn't complete */ | |
1101 | continue; | |
1102 | ||
1103 | default: | |
1104 | /* Any kind of failure? Store the data away, | |
1105 | * if there's nothing stored yet. */ | |
934e9b10 | 1106 | |
019036a4 LP |
1107 | if (state == DNS_TRANSACTION_SUCCESS) |
1108 | continue; | |
934e9b10 | 1109 | |
d38d5ca6 | 1110 | q->answer = dns_answer_unref(q->answer); |
019036a4 LP |
1111 | q->answer_rcode = t->answer_rcode; |
1112 | q->answer_dnssec_result = t->answer_dnssec_result; | |
934e9b10 | 1113 | |
019036a4 | 1114 | state = t->state; |
801ad6a6 | 1115 | break; |
74b2466e | 1116 | } |
801ad6a6 | 1117 | } |
74b2466e | 1118 | |
019036a4 LP |
1119 | if (state == DNS_TRANSACTION_SUCCESS) { |
1120 | q->answer_authenticated = has_authenticated && !has_non_authenticated; | |
1121 | q->answer_dnssec_result = q->answer_authenticated ? dnssec_result_authenticated : dnssec_result_non_authenticated; | |
1122 | } | |
1123 | ||
801ad6a6 LP |
1124 | q->answer_protocol = c->scope->protocol; |
1125 | q->answer_family = c->scope->family; | |
934e9b10 | 1126 | |
801ad6a6 LP |
1127 | dns_search_domain_unref(q->answer_search_domain); |
1128 | q->answer_search_domain = dns_search_domain_ref(c->search_domain); | |
7e8e0422 | 1129 | |
801ad6a6 LP |
1130 | dns_query_synthesize_reply(q, &state); |
1131 | dns_query_complete(q, state); | |
1132 | } | |
934e9b10 | 1133 | |
801ad6a6 | 1134 | void dns_query_ready(DnsQuery *q) { |
74b2466e | 1135 | |
801ad6a6 LP |
1136 | DnsQueryCandidate *bad = NULL, *c; |
1137 | bool pending = false; | |
74b2466e | 1138 | |
801ad6a6 | 1139 | assert(q); |
547973de | 1140 | assert(DNS_TRANSACTION_IS_LIVE(q->state)); |
e4501ed4 | 1141 | |
801ad6a6 LP |
1142 | /* Note that this call might invalidate the query. Callers |
1143 | * should hence not attempt to access the query or transaction | |
1144 | * after calling this function, unless the block_ready | |
1145 | * counter was explicitly bumped before doing so. */ | |
1146 | ||
1147 | if (q->block_ready > 0) | |
1148 | return; | |
1149 | ||
1150 | LIST_FOREACH(candidates_by_query, c, q->candidates) { | |
1151 | DnsTransactionState state; | |
1152 | ||
1153 | state = dns_query_candidate_state(c); | |
1154 | switch (state) { | |
1155 | ||
1156 | case DNS_TRANSACTION_SUCCESS: | |
547973de | 1157 | /* One of the candidates is successful, |
801ad6a6 LP |
1158 | * let's use it, and copy its data out */ |
1159 | dns_query_accept(q, c); | |
e4501ed4 LP |
1160 | return; |
1161 | ||
801ad6a6 | 1162 | case DNS_TRANSACTION_NULL: |
547973de LP |
1163 | case DNS_TRANSACTION_PENDING: |
1164 | case DNS_TRANSACTION_VALIDATING: | |
1165 | /* One of the candidates is still going on, | |
1166 | * let's maybe wait for it */ | |
801ad6a6 LP |
1167 | pending = true; |
1168 | break; | |
e4501ed4 | 1169 | |
801ad6a6 LP |
1170 | default: |
1171 | /* Any kind of failure */ | |
1172 | bad = c; | |
1173 | break; | |
1174 | } | |
faa133f3 | 1175 | } |
74b2466e | 1176 | |
801ad6a6 LP |
1177 | if (pending) |
1178 | return; | |
2a1037af | 1179 | |
801ad6a6 | 1180 | dns_query_accept(q, bad); |
74b2466e | 1181 | } |
8ba9fd9c | 1182 | |
45ec7efb | 1183 | static int dns_query_cname_redirect(DnsQuery *q, const DnsResourceRecord *cname) { |
23b298bc LP |
1184 | _cleanup_(dns_question_unrefp) DnsQuestion *nq_idna = NULL, *nq_utf8 = NULL; |
1185 | int r, k; | |
8ba9fd9c LP |
1186 | |
1187 | assert(q); | |
1188 | ||
45ec7efb | 1189 | q->n_cname_redirects ++; |
faa133f3 | 1190 | if (q->n_cname_redirects > CNAME_MAX) |
8ba9fd9c LP |
1191 | return -ELOOP; |
1192 | ||
23b298bc | 1193 | r = dns_question_cname_redirect(q->question_idna, cname, &nq_idna); |
faa133f3 LP |
1194 | if (r < 0) |
1195 | return r; | |
23b298bc | 1196 | else if (r > 0) |
8ec76e6a | 1197 | log_debug("Following CNAME/DNAME %s → %s.", dns_question_first_name(q->question_idna), dns_question_first_name(nq_idna)); |
23b298bc LP |
1198 | |
1199 | k = dns_question_is_equal(q->question_idna, q->question_utf8); | |
1200 | if (k < 0) | |
1201 | return r; | |
1202 | if (k > 0) { | |
1203 | /* Same question? Shortcut new question generation */ | |
1204 | nq_utf8 = dns_question_ref(nq_idna); | |
1205 | k = r; | |
1206 | } else { | |
1207 | k = dns_question_cname_redirect(q->question_utf8, cname, &nq_utf8); | |
1208 | if (k < 0) | |
1209 | return k; | |
1210 | else if (k > 0) | |
8ec76e6a | 1211 | log_debug("Following UTF8 CNAME/DNAME %s → %s.", dns_question_first_name(q->question_utf8), dns_question_first_name(nq_utf8)); |
23b298bc | 1212 | } |
8ba9fd9c | 1213 | |
23b298bc LP |
1214 | if (r == 0 && k == 0) /* No actual cname happened? */ |
1215 | return -ELOOP; | |
1216 | ||
1217 | dns_question_unref(q->question_idna); | |
1218 | q->question_idna = nq_idna; | |
1219 | nq_idna = NULL; | |
bc7669cf | 1220 | |
23b298bc LP |
1221 | dns_question_unref(q->question_utf8); |
1222 | q->question_utf8 = nq_utf8; | |
1223 | nq_utf8 = NULL; | |
8ba9fd9c | 1224 | |
7820b320 LP |
1225 | dns_query_free_candidates(q); |
1226 | dns_query_reset_answer(q); | |
ec2c5e43 | 1227 | q->state = DNS_TRANSACTION_NULL; |
322345fd | 1228 | |
59a89990 LP |
1229 | /* Turn off searching for the new name */ |
1230 | q->flags |= SD_RESOLVED_NO_SEARCH; | |
1231 | ||
8ba9fd9c LP |
1232 | return 0; |
1233 | } | |
82bd6ddd | 1234 | |
45ec7efb LP |
1235 | int dns_query_process_cname(DnsQuery *q) { |
1236 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *cname = NULL; | |
23b298bc | 1237 | DnsQuestion *question; |
45ec7efb LP |
1238 | DnsResourceRecord *rr; |
1239 | int r; | |
1240 | ||
1241 | assert(q); | |
1242 | ||
7588460a TG |
1243 | if (!IN_SET(q->state, DNS_TRANSACTION_SUCCESS, DNS_TRANSACTION_NULL)) |
1244 | return DNS_QUERY_NOMATCH; | |
45ec7efb | 1245 | |
23b298bc | 1246 | question = dns_query_question_for_protocol(q, q->answer_protocol); |
45ec7efb | 1247 | |
23b298bc LP |
1248 | DNS_ANSWER_FOREACH(rr, q->answer) { |
1249 | r = dns_question_matches_rr(question, rr, DNS_SEARCH_DOMAIN_NAME(q->answer_search_domain)); | |
45ec7efb LP |
1250 | if (r < 0) |
1251 | return r; | |
1252 | if (r > 0) | |
7588460a | 1253 | return DNS_QUERY_MATCH; /* The answer matches directly, no need to follow cnames */ |
45ec7efb | 1254 | |
542e0c84 | 1255 | r = dns_question_matches_cname_or_dname(question, rr, DNS_SEARCH_DOMAIN_NAME(q->answer_search_domain)); |
45ec7efb LP |
1256 | if (r < 0) |
1257 | return r; | |
1258 | if (r > 0 && !cname) | |
1259 | cname = dns_resource_record_ref(rr); | |
1260 | } | |
1261 | ||
1262 | if (!cname) | |
7588460a | 1263 | return DNS_QUERY_NOMATCH; /* No match and no cname to follow */ |
45ec7efb LP |
1264 | |
1265 | if (q->flags & SD_RESOLVED_NO_CNAME) | |
1266 | return -ELOOP; | |
1267 | ||
1268 | /* OK, let's actually follow the CNAME */ | |
1269 | r = dns_query_cname_redirect(q, cname); | |
1270 | if (r < 0) | |
1271 | return r; | |
1272 | ||
1273 | /* Let's see if the answer can already answer the new | |
1274 | * redirected question */ | |
7588460a TG |
1275 | r = dns_query_process_cname(q); |
1276 | if (r != DNS_QUERY_NOMATCH) | |
1277 | return r; | |
45ec7efb LP |
1278 | |
1279 | /* OK, it cannot, let's begin with the new query */ | |
1280 | r = dns_query_go(q); | |
1281 | if (r < 0) | |
1282 | return r; | |
1283 | ||
7588460a | 1284 | return DNS_QUERY_RESTARTED; /* We restarted the query for a new cname */ |
45ec7efb LP |
1285 | } |
1286 | ||
82bd6ddd LP |
1287 | static int on_bus_track(sd_bus_track *t, void *userdata) { |
1288 | DnsQuery *q = userdata; | |
1289 | ||
1290 | assert(t); | |
1291 | assert(q); | |
1292 | ||
1293 | log_debug("Client of active query vanished, aborting query."); | |
1294 | dns_query_complete(q, DNS_TRANSACTION_ABORTED); | |
1295 | return 0; | |
1296 | } | |
1297 | ||
966c66e3 | 1298 | int dns_query_bus_track(DnsQuery *q, sd_bus_message *m) { |
82bd6ddd LP |
1299 | int r; |
1300 | ||
1301 | assert(q); | |
1302 | assert(m); | |
1303 | ||
1304 | if (!q->bus_track) { | |
966c66e3 | 1305 | r = sd_bus_track_new(sd_bus_message_get_bus(m), &q->bus_track, on_bus_track, q); |
82bd6ddd LP |
1306 | if (r < 0) |
1307 | return r; | |
1308 | } | |
1309 | ||
1310 | r = sd_bus_track_add_sender(q->bus_track, m); | |
1311 | if (r < 0) | |
1312 | return r; | |
1313 | ||
1314 | return 0; | |
1315 | } | |
23b298bc LP |
1316 | |
1317 | DnsQuestion* dns_query_question_for_protocol(DnsQuery *q, DnsProtocol protocol) { | |
1318 | assert(q); | |
1319 | ||
1320 | switch (protocol) { | |
1321 | ||
1322 | case DNS_PROTOCOL_DNS: | |
1323 | return q->question_idna; | |
1324 | ||
1325 | case DNS_PROTOCOL_MDNS: | |
1326 | case DNS_PROTOCOL_LLMNR: | |
1327 | return q->question_utf8; | |
1328 | ||
1329 | default: | |
1330 | return NULL; | |
1331 | } | |
1332 | } | |
1333 | ||
1334 | const char *dns_query_string(DnsQuery *q) { | |
1335 | const char *name; | |
1336 | int r; | |
1337 | ||
1338 | /* Returns a somewhat useful human-readable lookup key string for this query */ | |
1339 | ||
1340 | if (q->request_address_string) | |
1341 | return q->request_address_string; | |
1342 | ||
1343 | if (q->request_address_valid) { | |
1344 | r = in_addr_to_string(q->request_family, &q->request_address, &q->request_address_string); | |
1345 | if (r >= 0) | |
1346 | return q->request_address_string; | |
1347 | } | |
1348 | ||
1349 | name = dns_question_first_name(q->question_utf8); | |
1350 | if (name) | |
1351 | return name; | |
1352 | ||
1353 | return dns_question_first_name(q->question_idna); | |
1354 | } |