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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" |
839a4a20 | 27 | #include "resolved-dns-synthesize.h" |
23b298bc | 28 | #include "string-util.h" |
74b2466e | 29 | |
0c903ae7 | 30 | /* How long to wait for the query in total */ |
74b2466e | 31 | #define QUERY_TIMEOUT_USEC (30 * USEC_PER_SEC) |
0c903ae7 | 32 | |
8ba9fd9c | 33 | #define CNAME_MAX 8 |
39762fdf | 34 | #define QUERIES_MAX 2048 |
45ec7efb | 35 | #define AUXILIARY_QUERIES_MAX 64 |
8ba9fd9c | 36 | |
801ad6a6 LP |
37 | static int dns_query_candidate_new(DnsQueryCandidate **ret, DnsQuery *q, DnsScope *s) { |
38 | DnsQueryCandidate *c; | |
74b2466e | 39 | |
801ad6a6 | 40 | assert(ret); |
faa133f3 | 41 | assert(q); |
801ad6a6 | 42 | assert(s); |
74b2466e | 43 | |
801ad6a6 LP |
44 | c = new0(DnsQueryCandidate, 1); |
45 | if (!c) | |
46 | return -ENOMEM; | |
47 | ||
48 | c->query = q; | |
49 | c->scope = s; | |
50 | ||
51 | LIST_PREPEND(candidates_by_query, q->candidates, c); | |
52 | LIST_PREPEND(candidates_by_scope, s->query_candidates, c); | |
53 | ||
54 | *ret = c; | |
55 | return 0; | |
56 | } | |
57 | ||
58 | static void dns_query_candidate_stop(DnsQueryCandidate *c) { | |
59 | DnsTransaction *t; | |
74b2466e | 60 | |
801ad6a6 LP |
61 | assert(c); |
62 | ||
63 | while ((t = set_steal_first(c->transactions))) { | |
547973de | 64 | set_remove(t->notify_query_candidates, c); |
ec2c5e43 | 65 | dns_transaction_gc(t); |
74b2466e | 66 | } |
74b2466e LP |
67 | } |
68 | ||
801ad6a6 LP |
69 | DnsQueryCandidate* dns_query_candidate_free(DnsQueryCandidate *c) { |
70 | ||
71 | if (!c) | |
72 | return NULL; | |
73 | ||
74 | dns_query_candidate_stop(c); | |
75 | ||
76 | set_free(c->transactions); | |
77 | dns_search_domain_unref(c->search_domain); | |
78 | ||
79 | if (c->query) | |
80 | LIST_REMOVE(candidates_by_query, c->query->candidates, c); | |
81 | ||
82 | if (c->scope) | |
83 | LIST_REMOVE(candidates_by_scope, c->scope->query_candidates, c); | |
84 | ||
85 | free(c); | |
86 | ||
87 | return NULL; | |
88 | } | |
89 | ||
90 | static int dns_query_candidate_next_search_domain(DnsQueryCandidate *c) { | |
801ad6a6 LP |
91 | DnsSearchDomain *next = NULL; |
92 | ||
93 | assert(c); | |
94 | ||
95 | if (c->search_domain && c->search_domain->linked) { | |
96 | next = c->search_domain->domains_next; | |
97 | ||
6627b7e2 LP |
98 | if (!next) /* We hit the end of the list */ |
99 | return 0; | |
801ad6a6 LP |
100 | |
101 | } else { | |
801ad6a6 LP |
102 | next = dns_scope_get_search_domains(c->scope); |
103 | ||
6627b7e2 | 104 | if (!next) /* OK, there's nothing. */ |
801ad6a6 LP |
105 | return 0; |
106 | } | |
107 | ||
108 | dns_search_domain_unref(c->search_domain); | |
109 | c->search_domain = dns_search_domain_ref(next); | |
6627b7e2 | 110 | |
801ad6a6 LP |
111 | return 1; |
112 | } | |
113 | ||
114 | static int dns_query_candidate_add_transaction(DnsQueryCandidate *c, DnsResourceKey *key) { | |
115 | DnsTransaction *t; | |
116 | int r; | |
117 | ||
118 | assert(c); | |
119 | assert(key); | |
120 | ||
801ad6a6 LP |
121 | t = dns_scope_find_transaction(c->scope, key, true); |
122 | if (!t) { | |
123 | r = dns_transaction_new(&t, c->scope, key); | |
124 | if (r < 0) | |
125 | return r; | |
547973de LP |
126 | } else { |
127 | if (set_contains(c->transactions, t)) | |
128 | return 0; | |
801ad6a6 LP |
129 | } |
130 | ||
547973de LP |
131 | r = set_ensure_allocated(&c->transactions, NULL); |
132 | if (r < 0) | |
133 | goto gc; | |
134 | ||
135 | r = set_ensure_allocated(&t->notify_query_candidates, NULL); | |
801ad6a6 LP |
136 | if (r < 0) |
137 | goto gc; | |
138 | ||
547973de | 139 | r = set_put(t->notify_query_candidates, c); |
801ad6a6 LP |
140 | if (r < 0) |
141 | goto gc; | |
142 | ||
143 | r = set_put(c->transactions, t); | |
144 | if (r < 0) { | |
547973de | 145 | (void) set_remove(t->notify_query_candidates, c); |
801ad6a6 LP |
146 | goto gc; |
147 | } | |
148 | ||
547973de | 149 | return 1; |
801ad6a6 LP |
150 | |
151 | gc: | |
152 | dns_transaction_gc(t); | |
153 | return r; | |
154 | } | |
155 | ||
156 | static int dns_query_candidate_go(DnsQueryCandidate *c) { | |
157 | DnsTransaction *t; | |
158 | Iterator i; | |
159 | int r; | |
160 | ||
161 | assert(c); | |
162 | ||
163 | /* Start the transactions that are not started yet */ | |
164 | SET_FOREACH(t, c->transactions, i) { | |
165 | if (t->state != DNS_TRANSACTION_NULL) | |
166 | continue; | |
167 | ||
168 | r = dns_transaction_go(t); | |
169 | if (r < 0) | |
170 | return r; | |
171 | } | |
172 | ||
173 | return 0; | |
174 | } | |
175 | ||
176 | static DnsTransactionState dns_query_candidate_state(DnsQueryCandidate *c) { | |
177 | DnsTransactionState state = DNS_TRANSACTION_NO_SERVERS; | |
178 | DnsTransaction *t; | |
179 | Iterator i; | |
180 | ||
181 | assert(c); | |
182 | ||
183 | if (c->error_code != 0) | |
184 | return DNS_TRANSACTION_RESOURCES; | |
185 | ||
186 | SET_FOREACH(t, c->transactions, i) { | |
187 | ||
188 | switch (t->state) { | |
189 | ||
5264131a LP |
190 | case DNS_TRANSACTION_NULL: |
191 | /* If there's a NULL transaction pending, then | |
192 | * this means not all transactions where | |
193 | * started yet, and we were called from within | |
194 | * the stackframe that is supposed to start | |
195 | * remaining transactions. In this case, | |
196 | * simply claim the candidate is pending. */ | |
197 | ||
801ad6a6 | 198 | case DNS_TRANSACTION_PENDING: |
547973de LP |
199 | case DNS_TRANSACTION_VALIDATING: |
200 | /* If there's one transaction currently in | |
201 | * VALIDATING state, then this means there's | |
202 | * also one in PENDING state, hence we can | |
203 | * return PENDING immediately. */ | |
204 | return DNS_TRANSACTION_PENDING; | |
801ad6a6 LP |
205 | |
206 | case DNS_TRANSACTION_SUCCESS: | |
207 | state = t->state; | |
208 | break; | |
209 | ||
210 | default: | |
211 | if (state != DNS_TRANSACTION_SUCCESS) | |
212 | state = t->state; | |
213 | ||
214 | break; | |
215 | } | |
216 | } | |
217 | ||
218 | return state; | |
219 | } | |
220 | ||
221 | static int dns_query_candidate_setup_transactions(DnsQueryCandidate *c) { | |
23b298bc | 222 | DnsQuestion *question; |
801ad6a6 LP |
223 | DnsResourceKey *key; |
224 | int n = 0, r; | |
225 | ||
226 | assert(c); | |
227 | ||
228 | dns_query_candidate_stop(c); | |
229 | ||
23b298bc LP |
230 | question = dns_query_question_for_protocol(c->query, c->scope->protocol); |
231 | ||
801ad6a6 | 232 | /* Create one transaction per question key */ |
23b298bc | 233 | DNS_QUESTION_FOREACH(key, question) { |
801ad6a6 LP |
234 | _cleanup_(dns_resource_key_unrefp) DnsResourceKey *new_key = NULL; |
235 | ||
236 | if (c->search_domain) { | |
237 | r = dns_resource_key_new_append_suffix(&new_key, key, c->search_domain->name); | |
238 | if (r < 0) | |
239 | goto fail; | |
240 | } | |
241 | ||
242 | r = dns_query_candidate_add_transaction(c, new_key ?: key); | |
243 | if (r < 0) | |
244 | goto fail; | |
245 | ||
246 | n++; | |
247 | } | |
248 | ||
249 | return n; | |
250 | ||
251 | fail: | |
252 | dns_query_candidate_stop(c); | |
253 | return r; | |
254 | } | |
255 | ||
547973de | 256 | void dns_query_candidate_notify(DnsQueryCandidate *c) { |
801ad6a6 LP |
257 | DnsTransactionState state; |
258 | int r; | |
259 | ||
260 | assert(c); | |
261 | ||
262 | state = dns_query_candidate_state(c); | |
263 | ||
547973de | 264 | if (DNS_TRANSACTION_IS_LIVE(state)) |
801ad6a6 LP |
265 | return; |
266 | ||
267 | if (state != DNS_TRANSACTION_SUCCESS && c->search_domain) { | |
268 | ||
269 | r = dns_query_candidate_next_search_domain(c); | |
270 | if (r < 0) | |
271 | goto fail; | |
272 | ||
273 | if (r > 0) { | |
274 | /* OK, there's another search domain to try, let's do so. */ | |
275 | ||
276 | r = dns_query_candidate_setup_transactions(c); | |
277 | if (r < 0) | |
278 | goto fail; | |
279 | ||
280 | if (r > 0) { | |
281 | /* New transactions where queued. Start them and wait */ | |
282 | ||
283 | r = dns_query_candidate_go(c); | |
284 | if (r < 0) | |
285 | goto fail; | |
286 | ||
287 | return; | |
288 | } | |
289 | } | |
290 | ||
291 | } | |
292 | ||
293 | dns_query_ready(c->query); | |
294 | return; | |
295 | ||
296 | fail: | |
297 | log_warning_errno(r, "Failed to follow search domains: %m"); | |
298 | c->error_code = r; | |
299 | dns_query_ready(c->query); | |
300 | } | |
301 | ||
302 | static void dns_query_stop(DnsQuery *q) { | |
303 | DnsQueryCandidate *c; | |
304 | ||
305 | assert(q); | |
306 | ||
307 | q->timeout_event_source = sd_event_source_unref(q->timeout_event_source); | |
308 | ||
309 | LIST_FOREACH(candidates_by_query, c, q->candidates) | |
310 | dns_query_candidate_stop(c); | |
311 | } | |
312 | ||
7820b320 LP |
313 | static void dns_query_free_candidates(DnsQuery *q) { |
314 | assert(q); | |
315 | ||
316 | while (q->candidates) | |
317 | dns_query_candidate_free(q->candidates); | |
318 | } | |
319 | ||
320 | static void dns_query_reset_answer(DnsQuery *q) { | |
321 | assert(q); | |
322 | ||
323 | q->answer = dns_answer_unref(q->answer); | |
324 | q->answer_rcode = 0; | |
325 | q->answer_dnssec_result = _DNSSEC_RESULT_INVALID; | |
326 | q->answer_authenticated = false; | |
327 | q->answer_protocol = _DNS_PROTOCOL_INVALID; | |
328 | q->answer_family = AF_UNSPEC; | |
329 | q->answer_search_domain = dns_search_domain_unref(q->answer_search_domain); | |
330 | } | |
331 | ||
74b2466e | 332 | DnsQuery *dns_query_free(DnsQuery *q) { |
74b2466e LP |
333 | if (!q) |
334 | return NULL; | |
335 | ||
45ec7efb LP |
336 | while (q->auxiliary_queries) |
337 | dns_query_free(q->auxiliary_queries); | |
338 | ||
339 | if (q->auxiliary_for) { | |
340 | assert(q->auxiliary_for->n_auxiliary_queries > 0); | |
341 | q->auxiliary_for->n_auxiliary_queries--; | |
342 | LIST_REMOVE(auxiliary_queries, q->auxiliary_for->auxiliary_queries, q); | |
343 | } | |
344 | ||
7820b320 | 345 | dns_query_free_candidates(q); |
322345fd | 346 | |
23b298bc LP |
347 | dns_question_unref(q->question_idna); |
348 | dns_question_unref(q->question_utf8); | |
7820b320 LP |
349 | |
350 | dns_query_reset_answer(q); | |
322345fd | 351 | |
ec2c5e43 | 352 | sd_bus_message_unref(q->request); |
82bd6ddd | 353 | sd_bus_track_unref(q->bus_track); |
74b2466e | 354 | |
23b298bc LP |
355 | free(q->request_address_string); |
356 | ||
39762fdf | 357 | if (q->manager) { |
74b2466e | 358 | LIST_REMOVE(queries, q->manager->dns_queries, q); |
39762fdf LP |
359 | q->manager->n_dns_queries--; |
360 | } | |
74b2466e | 361 | |
74b2466e LP |
362 | free(q); |
363 | ||
364 | return NULL; | |
365 | } | |
366 | ||
23b298bc LP |
367 | int dns_query_new( |
368 | Manager *m, | |
369 | DnsQuery **ret, | |
370 | DnsQuestion *question_utf8, | |
371 | DnsQuestion *question_idna, | |
372 | int ifindex, uint64_t flags) { | |
373 | ||
74b2466e | 374 | _cleanup_(dns_query_freep) DnsQuery *q = NULL; |
23b298bc LP |
375 | DnsResourceKey *key; |
376 | bool good = false; | |
faa133f3 | 377 | int r; |
74b2466e LP |
378 | |
379 | assert(m); | |
380 | ||
23b298bc LP |
381 | if (dns_question_size(question_utf8) > 0) { |
382 | r = dns_question_is_valid_for_query(question_utf8); | |
383 | if (r < 0) | |
384 | return r; | |
385 | if (r == 0) | |
386 | return -EINVAL; | |
387 | ||
388 | good = true; | |
389 | } | |
390 | ||
391 | /* If the IDNA and UTF8 questions are the same, merge their references */ | |
392 | r = dns_question_is_equal(question_idna, question_utf8); | |
faa133f3 LP |
393 | if (r < 0) |
394 | return r; | |
23b298bc LP |
395 | if (r > 0) |
396 | question_idna = question_utf8; | |
397 | else { | |
398 | if (dns_question_size(question_idna) > 0) { | |
399 | r = dns_question_is_valid_for_query(question_idna); | |
400 | if (r < 0) | |
401 | return r; | |
402 | if (r == 0) | |
403 | return -EINVAL; | |
404 | ||
405 | good = true; | |
406 | } | |
407 | } | |
408 | ||
409 | if (!good) /* don't allow empty queries */ | |
410 | return -EINVAL; | |
74b2466e | 411 | |
39762fdf LP |
412 | if (m->n_dns_queries >= QUERIES_MAX) |
413 | return -EBUSY; | |
414 | ||
74b2466e LP |
415 | q = new0(DnsQuery, 1); |
416 | if (!q) | |
417 | return -ENOMEM; | |
418 | ||
23b298bc LP |
419 | q->question_utf8 = dns_question_ref(question_utf8); |
420 | q->question_idna = dns_question_ref(question_idna); | |
51323288 LP |
421 | q->ifindex = ifindex; |
422 | q->flags = flags; | |
7820b320 | 423 | q->answer_dnssec_result = _DNSSEC_RESULT_INVALID; |
801ad6a6 | 424 | q->answer_protocol = _DNS_PROTOCOL_INVALID; |
7820b320 | 425 | q->answer_family = AF_UNSPEC; |
322345fd | 426 | |
23b298bc LP |
427 | /* First dump UTF8 question */ |
428 | DNS_QUESTION_FOREACH(key, question_utf8) { | |
429 | _cleanup_free_ char *p = NULL; | |
e4501ed4 | 430 | |
23b298bc | 431 | r = dns_resource_key_to_string(key, &p); |
e4501ed4 LP |
432 | if (r < 0) |
433 | return r; | |
434 | ||
23b298bc LP |
435 | log_debug("Looking up RR for %s.", strstrip(p)); |
436 | } | |
437 | ||
438 | /* And then dump the IDNA question, but only what hasn't been dumped already through the UTF8 question. */ | |
439 | DNS_QUESTION_FOREACH(key, question_idna) { | |
440 | _cleanup_free_ char *p = NULL; | |
441 | ||
442 | r = dns_question_contains(question_utf8, key); | |
443 | if (r < 0) | |
444 | return r; | |
445 | if (r > 0) | |
446 | continue; | |
447 | ||
448 | r = dns_resource_key_to_string(key, &p); | |
449 | if (r < 0) | |
450 | return r; | |
451 | ||
452 | log_debug("Looking up IDNA RR for %s.", strstrip(p)); | |
74b2466e LP |
453 | } |
454 | ||
455 | LIST_PREPEND(queries, m->dns_queries, q); | |
39762fdf | 456 | m->n_dns_queries++; |
74b2466e LP |
457 | q->manager = m; |
458 | ||
8ba9fd9c LP |
459 | if (ret) |
460 | *ret = q; | |
461 | q = NULL; | |
462 | ||
463 | return 0; | |
464 | } | |
465 | ||
45ec7efb LP |
466 | int dns_query_make_auxiliary(DnsQuery *q, DnsQuery *auxiliary_for) { |
467 | assert(q); | |
468 | assert(auxiliary_for); | |
469 | ||
470 | /* Ensure that that the query is not auxiliary yet, and | |
471 | * nothing else is auxiliary to it either */ | |
472 | assert(!q->auxiliary_for); | |
473 | assert(!q->auxiliary_queries); | |
474 | ||
475 | /* Ensure that the unit we shall be made auxiliary for isn't | |
476 | * auxiliary itself */ | |
477 | assert(!auxiliary_for->auxiliary_for); | |
478 | ||
479 | if (auxiliary_for->n_auxiliary_queries >= AUXILIARY_QUERIES_MAX) | |
480 | return -EAGAIN; | |
481 | ||
482 | LIST_PREPEND(auxiliary_queries, auxiliary_for->auxiliary_queries, q); | |
483 | q->auxiliary_for = auxiliary_for; | |
484 | ||
485 | auxiliary_for->n_auxiliary_queries++; | |
486 | return 0; | |
487 | } | |
488 | ||
ec2c5e43 | 489 | static void dns_query_complete(DnsQuery *q, DnsTransactionState state) { |
8ba9fd9c | 490 | assert(q); |
547973de LP |
491 | assert(!DNS_TRANSACTION_IS_LIVE(state)); |
492 | assert(DNS_TRANSACTION_IS_LIVE(q->state)); | |
8ba9fd9c | 493 | |
322345fd LP |
494 | /* Note that this call might invalidate the query. Callers |
495 | * should hence not attempt to access the query or transaction | |
496 | * after calling this function. */ | |
8ba9fd9c | 497 | |
8ba9fd9c LP |
498 | q->state = state; |
499 | ||
322345fd LP |
500 | dns_query_stop(q); |
501 | if (q->complete) | |
502 | q->complete(q); | |
8ba9fd9c LP |
503 | } |
504 | ||
505 | static int on_query_timeout(sd_event_source *s, usec_t usec, void *userdata) { | |
506 | DnsQuery *q = userdata; | |
507 | ||
508 | assert(s); | |
509 | assert(q); | |
510 | ||
ec2c5e43 | 511 | dns_query_complete(q, DNS_TRANSACTION_TIMEOUT); |
8ba9fd9c LP |
512 | return 0; |
513 | } | |
514 | ||
801ad6a6 LP |
515 | static int dns_query_add_candidate(DnsQuery *q, DnsScope *s) { |
516 | DnsQueryCandidate *c; | |
faa133f3 LP |
517 | int r; |
518 | ||
519 | assert(q); | |
ec2c5e43 | 520 | assert(s); |
faa133f3 | 521 | |
801ad6a6 | 522 | r = dns_query_candidate_new(&c, q, s); |
faa133f3 LP |
523 | if (r < 0) |
524 | return r; | |
525 | ||
801ad6a6 | 526 | /* If this a single-label domain on DNS, we might append a suitable search domain first. */ |
22f711bb | 527 | if ((q->flags & SD_RESOLVED_NO_SEARCH) == 0) { |
23b298bc | 528 | r = dns_scope_name_needs_search_domain(s, dns_question_first_name(q->question_idna)); |
22f711bb | 529 | if (r < 0) |
801ad6a6 | 530 | goto fail; |
22f711bb LP |
531 | if (r > 0) { |
532 | /* OK, we need a search domain now. Let's find one for this scope */ | |
533 | ||
534 | r = dns_query_candidate_next_search_domain(c); | |
535 | if (r <= 0) /* if there's no search domain, then we won't add any transaction. */ | |
536 | goto fail; | |
537 | } | |
faa133f3 LP |
538 | } |
539 | ||
801ad6a6 LP |
540 | r = dns_query_candidate_setup_transactions(c); |
541 | if (r < 0) | |
542 | goto fail; | |
543 | ||
faa133f3 LP |
544 | return 0; |
545 | ||
801ad6a6 LP |
546 | fail: |
547 | dns_query_candidate_free(c); | |
faa133f3 LP |
548 | return r; |
549 | } | |
550 | ||
78c6a153 | 551 | static int dns_query_synthesize_reply(DnsQuery *q, DnsTransactionState *state) { |
2a1037af | 552 | _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; |
839a4a20 LP |
553 | DnsProtocol protocol; |
554 | int family, r; | |
2a1037af LP |
555 | |
556 | assert(q); | |
557 | assert(state); | |
558 | ||
839a4a20 | 559 | /* Tries to synthesize localhost RR replies (and others) where appropriate */ |
2a1037af LP |
560 | |
561 | if (!IN_SET(*state, | |
3bbdc31d | 562 | DNS_TRANSACTION_RCODE_FAILURE, |
2a1037af LP |
563 | DNS_TRANSACTION_NO_SERVERS, |
564 | DNS_TRANSACTION_TIMEOUT, | |
edbcc1fd | 565 | DNS_TRANSACTION_ATTEMPTS_MAX_REACHED, |
0791110f LP |
566 | DNS_TRANSACTION_NETWORK_DOWN, |
567 | DNS_TRANSACTION_NOT_FOUND)) | |
78c6a153 | 568 | return 0; |
2a1037af | 569 | |
839a4a20 LP |
570 | r = dns_synthesize_answer( |
571 | q->manager, | |
572 | q->question_utf8, | |
573 | q->ifindex, | |
574 | q->flags, | |
575 | &answer, | |
576 | &protocol, | |
577 | &family); | |
2a1037af | 578 | |
839a4a20 LP |
579 | if (r <= 0) |
580 | return r; | |
2a1037af | 581 | |
839a4a20 | 582 | dns_query_reset_answer(q); |
2a1037af | 583 | |
2a1037af LP |
584 | q->answer = answer; |
585 | answer = NULL; | |
2a1037af | 586 | q->answer_rcode = DNS_RCODE_SUCCESS; |
839a4a20 LP |
587 | q->answer_protocol = protocol; |
588 | q->answer_family = family; | |
589 | q->answer_authenticated = true; | |
2a1037af LP |
590 | |
591 | *state = DNS_TRANSACTION_SUCCESS; | |
78c6a153 LP |
592 | |
593 | return 1; | |
2a1037af LP |
594 | } |
595 | ||
322345fd | 596 | int dns_query_go(DnsQuery *q) { |
8ba9fd9c LP |
597 | DnsScopeMatch found = DNS_SCOPE_NO; |
598 | DnsScope *s, *first = NULL; | |
801ad6a6 | 599 | DnsQueryCandidate *c; |
8ba9fd9c LP |
600 | int r; |
601 | ||
602 | assert(q); | |
603 | ||
ec2c5e43 | 604 | if (q->state != DNS_TRANSACTION_NULL) |
8ba9fd9c LP |
605 | return 0; |
606 | ||
8ba9fd9c | 607 | LIST_FOREACH(scopes, s, q->manager->dns_scopes) { |
74b2466e | 608 | DnsScopeMatch match; |
23b298bc LP |
609 | const char *name; |
610 | ||
611 | name = dns_question_first_name(dns_query_question_for_protocol(q, s->protocol)); | |
612 | if (!name) | |
613 | continue; | |
74b2466e | 614 | |
51323288 | 615 | match = dns_scope_good_domain(s, q->ifindex, q->flags, name); |
74b2466e LP |
616 | if (match < 0) |
617 | return match; | |
618 | ||
619 | if (match == DNS_SCOPE_NO) | |
620 | continue; | |
621 | ||
622 | found = match; | |
623 | ||
624 | if (match == DNS_SCOPE_YES) { | |
625 | first = s; | |
626 | break; | |
627 | } else { | |
628 | assert(match == DNS_SCOPE_MAYBE); | |
629 | ||
630 | if (!first) | |
631 | first = s; | |
632 | } | |
633 | } | |
634 | ||
2a1037af LP |
635 | if (found == DNS_SCOPE_NO) { |
636 | DnsTransactionState state = DNS_TRANSACTION_NO_SERVERS; | |
637 | ||
638 | dns_query_synthesize_reply(q, &state); | |
d634711b LP |
639 | dns_query_complete(q, state); |
640 | return 1; | |
2a1037af | 641 | } |
74b2466e | 642 | |
801ad6a6 | 643 | r = dns_query_add_candidate(q, first); |
74b2466e | 644 | if (r < 0) |
ec2c5e43 | 645 | goto fail; |
74b2466e | 646 | |
74b2466e LP |
647 | LIST_FOREACH(scopes, s, first->scopes_next) { |
648 | DnsScopeMatch match; | |
23b298bc LP |
649 | const char *name; |
650 | ||
651 | name = dns_question_first_name(dns_query_question_for_protocol(q, s->protocol)); | |
652 | if (!name) | |
653 | continue; | |
74b2466e | 654 | |
51323288 | 655 | match = dns_scope_good_domain(s, q->ifindex, q->flags, name); |
74b2466e | 656 | if (match < 0) |
ec2c5e43 | 657 | goto fail; |
74b2466e LP |
658 | |
659 | if (match != found) | |
660 | continue; | |
661 | ||
801ad6a6 | 662 | r = dns_query_add_candidate(q, s); |
74b2466e | 663 | if (r < 0) |
ec2c5e43 | 664 | goto fail; |
74b2466e LP |
665 | } |
666 | ||
faa133f3 | 667 | q->answer = dns_answer_unref(q->answer); |
faa133f3 | 668 | q->answer_rcode = 0; |
51323288 LP |
669 | q->answer_family = AF_UNSPEC; |
670 | q->answer_protocol = _DNS_PROTOCOL_INVALID; | |
74b2466e | 671 | |
9a015429 LP |
672 | r = sd_event_add_time( |
673 | q->manager->event, | |
674 | &q->timeout_event_source, | |
675 | clock_boottime_or_monotonic(), | |
676 | now(clock_boottime_or_monotonic()) + QUERY_TIMEOUT_USEC, 0, | |
677 | on_query_timeout, q); | |
74b2466e LP |
678 | if (r < 0) |
679 | goto fail; | |
680 | ||
aa4a9deb LP |
681 | (void) sd_event_source_set_description(q->timeout_event_source, "query-timeout"); |
682 | ||
ec2c5e43 | 683 | q->state = DNS_TRANSACTION_PENDING; |
faa133f3 | 684 | q->block_ready++; |
74b2466e | 685 | |
801ad6a6 LP |
686 | /* Start the transactions */ |
687 | LIST_FOREACH(candidates_by_query, c, q->candidates) { | |
688 | r = dns_query_candidate_go(c); | |
689 | if (r < 0) { | |
690 | q->block_ready--; | |
ec2c5e43 | 691 | goto fail; |
801ad6a6 | 692 | } |
74b2466e LP |
693 | } |
694 | ||
faa133f3 LP |
695 | q->block_ready--; |
696 | dns_query_ready(q); | |
322345fd | 697 | |
8ba9fd9c | 698 | return 1; |
74b2466e LP |
699 | |
700 | fail: | |
8ba9fd9c | 701 | dns_query_stop(q); |
74b2466e LP |
702 | return r; |
703 | } | |
704 | ||
801ad6a6 | 705 | static void dns_query_accept(DnsQuery *q, DnsQueryCandidate *c) { |
ec2c5e43 | 706 | DnsTransactionState state = DNS_TRANSACTION_NO_SERVERS; |
547973de | 707 | bool has_authenticated = false, has_non_authenticated = false; |
019036a4 | 708 | DnssecResult dnssec_result_authenticated = _DNSSEC_RESULT_INVALID, dnssec_result_non_authenticated = _DNSSEC_RESULT_INVALID; |
801ad6a6 | 709 | DnsTransaction *t; |
faa133f3 | 710 | Iterator i; |
547973de | 711 | int r; |
74b2466e LP |
712 | |
713 | assert(q); | |
714 | ||
801ad6a6 LP |
715 | if (!c) { |
716 | dns_query_synthesize_reply(q, &state); | |
717 | dns_query_complete(q, state); | |
74b2466e | 718 | return; |
801ad6a6 | 719 | } |
74b2466e | 720 | |
801ad6a6 | 721 | SET_FOREACH(t, c->transactions, i) { |
74b2466e | 722 | |
801ad6a6 | 723 | switch (t->state) { |
934e9b10 | 724 | |
801ad6a6 LP |
725 | case DNS_TRANSACTION_SUCCESS: { |
726 | /* We found a successfuly reply, merge it into the answer */ | |
547973de LP |
727 | r = dns_answer_extend(&q->answer, t->answer); |
728 | if (r < 0) { | |
801ad6a6 LP |
729 | dns_query_complete(q, DNS_TRANSACTION_RESOURCES); |
730 | return; | |
731 | } | |
019036a4 | 732 | |
ae6a4bbf | 733 | q->answer_rcode = t->answer_rcode; |
801ad6a6 | 734 | |
019036a4 | 735 | if (t->answer_authenticated) { |
931851e8 | 736 | has_authenticated = true; |
019036a4 LP |
737 | dnssec_result_authenticated = t->answer_dnssec_result; |
738 | } else { | |
931851e8 | 739 | has_non_authenticated = true; |
019036a4 LP |
740 | dnssec_result_non_authenticated = t->answer_dnssec_result; |
741 | } | |
931851e8 | 742 | |
801ad6a6 LP |
743 | state = DNS_TRANSACTION_SUCCESS; |
744 | break; | |
745 | } | |
746 | ||
801ad6a6 | 747 | case DNS_TRANSACTION_NULL: |
547973de LP |
748 | case DNS_TRANSACTION_PENDING: |
749 | case DNS_TRANSACTION_VALIDATING: | |
801ad6a6 LP |
750 | case DNS_TRANSACTION_ABORTED: |
751 | /* Ignore transactions that didn't complete */ | |
752 | continue; | |
753 | ||
754 | default: | |
755 | /* Any kind of failure? Store the data away, | |
756 | * if there's nothing stored yet. */ | |
934e9b10 | 757 | |
019036a4 LP |
758 | if (state == DNS_TRANSACTION_SUCCESS) |
759 | continue; | |
934e9b10 | 760 | |
d38d5ca6 | 761 | q->answer = dns_answer_unref(q->answer); |
019036a4 LP |
762 | q->answer_rcode = t->answer_rcode; |
763 | q->answer_dnssec_result = t->answer_dnssec_result; | |
934e9b10 | 764 | |
019036a4 | 765 | state = t->state; |
801ad6a6 | 766 | break; |
74b2466e | 767 | } |
801ad6a6 | 768 | } |
74b2466e | 769 | |
019036a4 LP |
770 | if (state == DNS_TRANSACTION_SUCCESS) { |
771 | q->answer_authenticated = has_authenticated && !has_non_authenticated; | |
772 | q->answer_dnssec_result = q->answer_authenticated ? dnssec_result_authenticated : dnssec_result_non_authenticated; | |
773 | } | |
774 | ||
801ad6a6 LP |
775 | q->answer_protocol = c->scope->protocol; |
776 | q->answer_family = c->scope->family; | |
934e9b10 | 777 | |
801ad6a6 LP |
778 | dns_search_domain_unref(q->answer_search_domain); |
779 | q->answer_search_domain = dns_search_domain_ref(c->search_domain); | |
7e8e0422 | 780 | |
801ad6a6 LP |
781 | dns_query_synthesize_reply(q, &state); |
782 | dns_query_complete(q, state); | |
783 | } | |
934e9b10 | 784 | |
801ad6a6 | 785 | void dns_query_ready(DnsQuery *q) { |
74b2466e | 786 | |
801ad6a6 LP |
787 | DnsQueryCandidate *bad = NULL, *c; |
788 | bool pending = false; | |
74b2466e | 789 | |
801ad6a6 | 790 | assert(q); |
547973de | 791 | assert(DNS_TRANSACTION_IS_LIVE(q->state)); |
e4501ed4 | 792 | |
801ad6a6 LP |
793 | /* Note that this call might invalidate the query. Callers |
794 | * should hence not attempt to access the query or transaction | |
795 | * after calling this function, unless the block_ready | |
796 | * counter was explicitly bumped before doing so. */ | |
797 | ||
798 | if (q->block_ready > 0) | |
799 | return; | |
800 | ||
801 | LIST_FOREACH(candidates_by_query, c, q->candidates) { | |
802 | DnsTransactionState state; | |
803 | ||
804 | state = dns_query_candidate_state(c); | |
805 | switch (state) { | |
806 | ||
807 | case DNS_TRANSACTION_SUCCESS: | |
547973de | 808 | /* One of the candidates is successful, |
801ad6a6 LP |
809 | * let's use it, and copy its data out */ |
810 | dns_query_accept(q, c); | |
e4501ed4 LP |
811 | return; |
812 | ||
801ad6a6 | 813 | case DNS_TRANSACTION_NULL: |
547973de LP |
814 | case DNS_TRANSACTION_PENDING: |
815 | case DNS_TRANSACTION_VALIDATING: | |
816 | /* One of the candidates is still going on, | |
817 | * let's maybe wait for it */ | |
801ad6a6 LP |
818 | pending = true; |
819 | break; | |
e4501ed4 | 820 | |
801ad6a6 LP |
821 | default: |
822 | /* Any kind of failure */ | |
823 | bad = c; | |
824 | break; | |
825 | } | |
faa133f3 | 826 | } |
74b2466e | 827 | |
801ad6a6 LP |
828 | if (pending) |
829 | return; | |
2a1037af | 830 | |
801ad6a6 | 831 | dns_query_accept(q, bad); |
74b2466e | 832 | } |
8ba9fd9c | 833 | |
45ec7efb | 834 | static int dns_query_cname_redirect(DnsQuery *q, const DnsResourceRecord *cname) { |
23b298bc LP |
835 | _cleanup_(dns_question_unrefp) DnsQuestion *nq_idna = NULL, *nq_utf8 = NULL; |
836 | int r, k; | |
8ba9fd9c LP |
837 | |
838 | assert(q); | |
839 | ||
45ec7efb | 840 | q->n_cname_redirects ++; |
faa133f3 | 841 | if (q->n_cname_redirects > CNAME_MAX) |
8ba9fd9c LP |
842 | return -ELOOP; |
843 | ||
23b298bc | 844 | r = dns_question_cname_redirect(q->question_idna, cname, &nq_idna); |
faa133f3 LP |
845 | if (r < 0) |
846 | return r; | |
23b298bc | 847 | else if (r > 0) |
8ec76e6a | 848 | log_debug("Following CNAME/DNAME %s → %s.", dns_question_first_name(q->question_idna), dns_question_first_name(nq_idna)); |
23b298bc LP |
849 | |
850 | k = dns_question_is_equal(q->question_idna, q->question_utf8); | |
851 | if (k < 0) | |
852 | return r; | |
853 | if (k > 0) { | |
854 | /* Same question? Shortcut new question generation */ | |
855 | nq_utf8 = dns_question_ref(nq_idna); | |
856 | k = r; | |
857 | } else { | |
858 | k = dns_question_cname_redirect(q->question_utf8, cname, &nq_utf8); | |
859 | if (k < 0) | |
860 | return k; | |
861 | else if (k > 0) | |
8ec76e6a | 862 | log_debug("Following UTF8 CNAME/DNAME %s → %s.", dns_question_first_name(q->question_utf8), dns_question_first_name(nq_utf8)); |
23b298bc | 863 | } |
8ba9fd9c | 864 | |
23b298bc LP |
865 | if (r == 0 && k == 0) /* No actual cname happened? */ |
866 | return -ELOOP; | |
867 | ||
868 | dns_question_unref(q->question_idna); | |
869 | q->question_idna = nq_idna; | |
870 | nq_idna = NULL; | |
bc7669cf | 871 | |
23b298bc LP |
872 | dns_question_unref(q->question_utf8); |
873 | q->question_utf8 = nq_utf8; | |
874 | nq_utf8 = NULL; | |
8ba9fd9c | 875 | |
7820b320 LP |
876 | dns_query_free_candidates(q); |
877 | dns_query_reset_answer(q); | |
ec2c5e43 | 878 | q->state = DNS_TRANSACTION_NULL; |
322345fd | 879 | |
59a89990 LP |
880 | /* Turn off searching for the new name */ |
881 | q->flags |= SD_RESOLVED_NO_SEARCH; | |
882 | ||
8ba9fd9c LP |
883 | return 0; |
884 | } | |
82bd6ddd | 885 | |
45ec7efb LP |
886 | int dns_query_process_cname(DnsQuery *q) { |
887 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *cname = NULL; | |
23b298bc | 888 | DnsQuestion *question; |
45ec7efb LP |
889 | DnsResourceRecord *rr; |
890 | int r; | |
891 | ||
892 | assert(q); | |
893 | ||
7588460a TG |
894 | if (!IN_SET(q->state, DNS_TRANSACTION_SUCCESS, DNS_TRANSACTION_NULL)) |
895 | return DNS_QUERY_NOMATCH; | |
45ec7efb | 896 | |
23b298bc | 897 | question = dns_query_question_for_protocol(q, q->answer_protocol); |
45ec7efb | 898 | |
23b298bc LP |
899 | DNS_ANSWER_FOREACH(rr, q->answer) { |
900 | r = dns_question_matches_rr(question, rr, DNS_SEARCH_DOMAIN_NAME(q->answer_search_domain)); | |
45ec7efb LP |
901 | if (r < 0) |
902 | return r; | |
903 | if (r > 0) | |
7588460a | 904 | return DNS_QUERY_MATCH; /* The answer matches directly, no need to follow cnames */ |
45ec7efb | 905 | |
542e0c84 | 906 | r = dns_question_matches_cname_or_dname(question, rr, DNS_SEARCH_DOMAIN_NAME(q->answer_search_domain)); |
45ec7efb LP |
907 | if (r < 0) |
908 | return r; | |
909 | if (r > 0 && !cname) | |
910 | cname = dns_resource_record_ref(rr); | |
911 | } | |
912 | ||
913 | if (!cname) | |
7588460a | 914 | return DNS_QUERY_NOMATCH; /* No match and no cname to follow */ |
45ec7efb LP |
915 | |
916 | if (q->flags & SD_RESOLVED_NO_CNAME) | |
917 | return -ELOOP; | |
918 | ||
919 | /* OK, let's actually follow the CNAME */ | |
920 | r = dns_query_cname_redirect(q, cname); | |
921 | if (r < 0) | |
922 | return r; | |
923 | ||
924 | /* Let's see if the answer can already answer the new | |
925 | * redirected question */ | |
7588460a TG |
926 | r = dns_query_process_cname(q); |
927 | if (r != DNS_QUERY_NOMATCH) | |
928 | return r; | |
45ec7efb LP |
929 | |
930 | /* OK, it cannot, let's begin with the new query */ | |
931 | r = dns_query_go(q); | |
932 | if (r < 0) | |
933 | return r; | |
934 | ||
7588460a | 935 | return DNS_QUERY_RESTARTED; /* We restarted the query for a new cname */ |
45ec7efb LP |
936 | } |
937 | ||
82bd6ddd LP |
938 | static int on_bus_track(sd_bus_track *t, void *userdata) { |
939 | DnsQuery *q = userdata; | |
940 | ||
941 | assert(t); | |
942 | assert(q); | |
943 | ||
944 | log_debug("Client of active query vanished, aborting query."); | |
945 | dns_query_complete(q, DNS_TRANSACTION_ABORTED); | |
946 | return 0; | |
947 | } | |
948 | ||
966c66e3 | 949 | int dns_query_bus_track(DnsQuery *q, sd_bus_message *m) { |
82bd6ddd LP |
950 | int r; |
951 | ||
952 | assert(q); | |
953 | assert(m); | |
954 | ||
955 | if (!q->bus_track) { | |
966c66e3 | 956 | r = sd_bus_track_new(sd_bus_message_get_bus(m), &q->bus_track, on_bus_track, q); |
82bd6ddd LP |
957 | if (r < 0) |
958 | return r; | |
959 | } | |
960 | ||
961 | r = sd_bus_track_add_sender(q->bus_track, m); | |
962 | if (r < 0) | |
963 | return r; | |
964 | ||
965 | return 0; | |
966 | } | |
23b298bc LP |
967 | |
968 | DnsQuestion* dns_query_question_for_protocol(DnsQuery *q, DnsProtocol protocol) { | |
969 | assert(q); | |
970 | ||
971 | switch (protocol) { | |
972 | ||
973 | case DNS_PROTOCOL_DNS: | |
974 | return q->question_idna; | |
975 | ||
976 | case DNS_PROTOCOL_MDNS: | |
977 | case DNS_PROTOCOL_LLMNR: | |
978 | return q->question_utf8; | |
979 | ||
980 | default: | |
981 | return NULL; | |
982 | } | |
983 | } | |
984 | ||
985 | const char *dns_query_string(DnsQuery *q) { | |
986 | const char *name; | |
987 | int r; | |
988 | ||
989 | /* Returns a somewhat useful human-readable lookup key string for this query */ | |
990 | ||
991 | if (q->request_address_string) | |
992 | return q->request_address_string; | |
993 | ||
994 | if (q->request_address_valid) { | |
995 | r = in_addr_to_string(q->request_family, &q->request_address, &q->request_address_string); | |
996 | if (r >= 0) | |
997 | return q->request_address_string; | |
998 | } | |
999 | ||
1000 | name = dns_question_first_name(q->question_utf8); | |
1001 | if (name) | |
1002 | return name; | |
1003 | ||
1004 | return dns_question_first_name(q->question_idna); | |
1005 | } |