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Commit | Line | Data |
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53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
faa133f3 LP |
2 | /*** |
3 | This file is part of systemd. | |
4 | ||
5 | Copyright 2014 Lennart Poettering | |
faa133f3 LP |
6 | ***/ |
7 | ||
b5efdb8a | 8 | #include "alloc-util.h" |
4ad7f276 | 9 | #include "dns-domain.h" |
07630cea | 10 | #include "resolved-dns-answer.h" |
72667f08 | 11 | #include "resolved-dns-dnssec.h" |
07630cea | 12 | #include "string-util.h" |
faa133f3 | 13 | |
da6053d0 | 14 | DnsAnswer *dns_answer_new(size_t n) { |
faa133f3 LP |
15 | DnsAnswer *a; |
16 | ||
78c6a153 | 17 | a = malloc0(offsetof(DnsAnswer, items) + sizeof(DnsAnswerItem) * n); |
faa133f3 LP |
18 | if (!a) |
19 | return NULL; | |
20 | ||
21 | a->n_ref = 1; | |
22 | a->n_allocated = n; | |
23 | ||
24 | return a; | |
25 | } | |
26 | ||
27 | DnsAnswer *dns_answer_ref(DnsAnswer *a) { | |
28 | if (!a) | |
29 | return NULL; | |
30 | ||
31 | assert(a->n_ref > 0); | |
32 | a->n_ref++; | |
33 | return a; | |
34 | } | |
35 | ||
d42800f1 LP |
36 | static void dns_answer_flush(DnsAnswer *a) { |
37 | DnsResourceRecord *rr; | |
38 | ||
39 | if (!a) | |
40 | return; | |
41 | ||
42 | DNS_ANSWER_FOREACH(rr, a) | |
43 | dns_resource_record_unref(rr); | |
44 | ||
45 | a->n_rrs = 0; | |
46 | } | |
47 | ||
faa133f3 LP |
48 | DnsAnswer *dns_answer_unref(DnsAnswer *a) { |
49 | if (!a) | |
50 | return NULL; | |
51 | ||
52 | assert(a->n_ref > 0); | |
53 | ||
54 | if (a->n_ref == 1) { | |
d42800f1 | 55 | dns_answer_flush(a); |
faa133f3 LP |
56 | free(a); |
57 | } else | |
58 | a->n_ref--; | |
59 | ||
60 | return NULL; | |
61 | } | |
62 | ||
105e1512 | 63 | static int dns_answer_add_raw(DnsAnswer *a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) { |
547973de LP |
64 | assert(rr); |
65 | ||
66 | if (!a) | |
67 | return -ENOSPC; | |
68 | ||
69 | if (a->n_rrs >= a->n_allocated) | |
70 | return -ENOSPC; | |
71 | ||
105e1512 LP |
72 | a->items[a->n_rrs++] = (DnsAnswerItem) { |
73 | .rr = dns_resource_record_ref(rr), | |
74 | .ifindex = ifindex, | |
75 | .flags = flags, | |
76 | }; | |
547973de LP |
77 | |
78 | return 1; | |
79 | } | |
80 | ||
81 | static int dns_answer_add_raw_all(DnsAnswer *a, DnsAnswer *source) { | |
82 | DnsResourceRecord *rr; | |
105e1512 | 83 | DnsAnswerFlags flags; |
547973de LP |
84 | int ifindex, r; |
85 | ||
105e1512 LP |
86 | DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, source) { |
87 | r = dns_answer_add_raw(a, rr, ifindex, flags); | |
547973de LP |
88 | if (r < 0) |
89 | return r; | |
90 | } | |
91 | ||
92 | return 0; | |
93 | } | |
94 | ||
105e1512 | 95 | int dns_answer_add(DnsAnswer *a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) { |
da6053d0 | 96 | size_t i; |
7e8e0422 LP |
97 | int r; |
98 | ||
faa133f3 LP |
99 | assert(rr); |
100 | ||
78c6a153 LP |
101 | if (!a) |
102 | return -ENOSPC; | |
c296dd2e LP |
103 | if (a->n_ref > 1) |
104 | return -EBUSY; | |
78c6a153 | 105 | |
7e8e0422 | 106 | for (i = 0; i < a->n_rrs; i++) { |
78c6a153 LP |
107 | if (a->items[i].ifindex != ifindex) |
108 | continue; | |
109 | ||
110 | r = dns_resource_record_equal(a->items[i].rr, rr); | |
7e8e0422 LP |
111 | if (r < 0) |
112 | return r; | |
113 | if (r > 0) { | |
7feea00b LP |
114 | /* Don't mix contradicting TTLs (see below) */ |
115 | if ((rr->ttl == 0) != (a->items[i].rr->ttl == 0)) | |
116 | return -EINVAL; | |
7e8e0422 | 117 | |
7feea00b LP |
118 | /* Entry already exists, keep the entry with |
119 | * the higher RR. */ | |
120 | if (rr->ttl > a->items[i].rr->ttl) { | |
7e8e0422 | 121 | dns_resource_record_ref(rr); |
78c6a153 LP |
122 | dns_resource_record_unref(a->items[i].rr); |
123 | a->items[i].rr = rr; | |
7e8e0422 LP |
124 | } |
125 | ||
105e1512 | 126 | a->items[i].flags |= flags; |
7e8e0422 LP |
127 | return 0; |
128 | } | |
7feea00b LP |
129 | |
130 | r = dns_resource_key_equal(a->items[i].rr->key, rr->key); | |
131 | if (r < 0) | |
132 | return r; | |
133 | if (r > 0) { | |
134 | /* There's already an RR of the same RRset in | |
135 | * place! Let's see if the TTLs more or less | |
136 | * match. We don't really care if they match | |
137 | * precisely, but we do care whether one is 0 | |
138 | * and the other is not. See RFC 2181, Section | |
13e785f7 | 139 | * 5.2. */ |
7feea00b LP |
140 | |
141 | if ((rr->ttl == 0) != (a->items[i].rr->ttl == 0)) | |
142 | return -EINVAL; | |
143 | } | |
7e8e0422 LP |
144 | } |
145 | ||
105e1512 | 146 | return dns_answer_add_raw(a, rr, ifindex, flags); |
547973de | 147 | } |
faa133f3 | 148 | |
547973de LP |
149 | static int dns_answer_add_all(DnsAnswer *a, DnsAnswer *b) { |
150 | DnsResourceRecord *rr; | |
105e1512 | 151 | DnsAnswerFlags flags; |
547973de | 152 | int ifindex, r; |
78c6a153 | 153 | |
105e1512 LP |
154 | DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, b) { |
155 | r = dns_answer_add(a, rr, ifindex, flags); | |
547973de LP |
156 | if (r < 0) |
157 | return r; | |
158 | } | |
159 | ||
160 | return 0; | |
161 | } | |
162 | ||
105e1512 | 163 | int dns_answer_add_extend(DnsAnswer **a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) { |
547973de LP |
164 | int r; |
165 | ||
166 | assert(a); | |
167 | assert(rr); | |
168 | ||
169 | r = dns_answer_reserve_or_clone(a, 1); | |
170 | if (r < 0) | |
171 | return r; | |
172 | ||
105e1512 | 173 | return dns_answer_add(*a, rr, ifindex, flags); |
7e8e0422 LP |
174 | } |
175 | ||
97ebebbc | 176 | int dns_answer_add_soa(DnsAnswer *a, const char *name, uint32_t ttl, int ifindex) { |
8bf52d3d LP |
177 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *soa = NULL; |
178 | ||
179 | soa = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_SOA, name); | |
180 | if (!soa) | |
181 | return -ENOMEM; | |
182 | ||
57f5ad31 LP |
183 | soa->ttl = ttl; |
184 | ||
8bf52d3d LP |
185 | soa->soa.mname = strdup(name); |
186 | if (!soa->soa.mname) | |
187 | return -ENOMEM; | |
188 | ||
189 | soa->soa.rname = strappend("root.", name); | |
190 | if (!soa->soa.rname) | |
191 | return -ENOMEM; | |
192 | ||
193 | soa->soa.serial = 1; | |
194 | soa->soa.refresh = 1; | |
195 | soa->soa.retry = 1; | |
196 | soa->soa.expire = 1; | |
57f5ad31 | 197 | soa->soa.minimum = ttl; |
8bf52d3d | 198 | |
97ebebbc | 199 | return dns_answer_add(a, soa, ifindex, DNS_ANSWER_AUTHENTICATED); |
8bf52d3d LP |
200 | } |
201 | ||
105e1512 LP |
202 | int dns_answer_match_key(DnsAnswer *a, const DnsResourceKey *key, DnsAnswerFlags *ret_flags) { |
203 | DnsAnswerFlags flags = 0, i_flags; | |
547973de | 204 | DnsResourceRecord *i; |
105e1512 | 205 | bool found = false; |
7e8e0422 LP |
206 | int r; |
207 | ||
7e8e0422 LP |
208 | assert(key); |
209 | ||
105e1512 | 210 | DNS_ANSWER_FOREACH_FLAGS(i, i_flags, a) { |
547973de | 211 | r = dns_resource_key_match_rr(key, i, NULL); |
7e8e0422 LP |
212 | if (r < 0) |
213 | return r; | |
105e1512 LP |
214 | if (r == 0) |
215 | continue; | |
216 | ||
217 | if (!ret_flags) | |
7e8e0422 | 218 | return 1; |
105e1512 LP |
219 | |
220 | if (found) | |
221 | flags &= i_flags; | |
222 | else { | |
223 | flags = i_flags; | |
224 | found = true; | |
225 | } | |
7e8e0422 LP |
226 | } |
227 | ||
105e1512 LP |
228 | if (ret_flags) |
229 | *ret_flags = flags; | |
230 | ||
231 | return found; | |
7e8e0422 LP |
232 | } |
233 | ||
105e1512 LP |
234 | int dns_answer_contains_rr(DnsAnswer *a, DnsResourceRecord *rr, DnsAnswerFlags *ret_flags) { |
235 | DnsAnswerFlags flags = 0, i_flags; | |
547973de | 236 | DnsResourceRecord *i; |
105e1512 | 237 | bool found = false; |
547973de | 238 | int r; |
5eefe544 | 239 | |
547973de | 240 | assert(rr); |
5eefe544 | 241 | |
105e1512 | 242 | DNS_ANSWER_FOREACH_FLAGS(i, i_flags, a) { |
547973de LP |
243 | r = dns_resource_record_equal(i, rr); |
244 | if (r < 0) | |
245 | return r; | |
105e1512 LP |
246 | if (r == 0) |
247 | continue; | |
248 | ||
249 | if (!ret_flags) | |
547973de | 250 | return 1; |
105e1512 LP |
251 | |
252 | if (found) | |
253 | flags &= i_flags; | |
254 | else { | |
255 | flags = i_flags; | |
256 | found = true; | |
257 | } | |
547973de | 258 | } |
5eefe544 | 259 | |
105e1512 LP |
260 | if (ret_flags) |
261 | *ret_flags = flags; | |
262 | ||
263 | return found; | |
264 | } | |
265 | ||
266 | int dns_answer_contains_key(DnsAnswer *a, const DnsResourceKey *key, DnsAnswerFlags *ret_flags) { | |
267 | DnsAnswerFlags flags = 0, i_flags; | |
268 | DnsResourceRecord *i; | |
269 | bool found = false; | |
270 | int r; | |
271 | ||
272 | assert(key); | |
273 | ||
274 | DNS_ANSWER_FOREACH_FLAGS(i, i_flags, a) { | |
275 | r = dns_resource_key_equal(i->key, key); | |
276 | if (r < 0) | |
277 | return r; | |
278 | if (r == 0) | |
279 | continue; | |
280 | ||
281 | if (!ret_flags) | |
282 | return true; | |
283 | ||
284 | if (found) | |
285 | flags &= i_flags; | |
286 | else { | |
287 | flags = i_flags; | |
288 | found = true; | |
289 | } | |
290 | } | |
291 | ||
292 | if (ret_flags) | |
293 | *ret_flags = flags; | |
294 | ||
295 | return found; | |
296 | } | |
297 | ||
298 | int dns_answer_contains_nsec_or_nsec3(DnsAnswer *a) { | |
299 | DnsResourceRecord *i; | |
300 | ||
301 | DNS_ANSWER_FOREACH(i, a) { | |
302 | if (IN_SET(i->key->type, DNS_TYPE_NSEC, DNS_TYPE_NSEC3)) | |
303 | return true; | |
304 | } | |
305 | ||
306 | return false; | |
5eefe544 TG |
307 | } |
308 | ||
e926785a LP |
309 | int dns_answer_contains_zone_nsec3(DnsAnswer *answer, const char *zone) { |
310 | DnsResourceRecord *rr; | |
311 | int r; | |
312 | ||
313 | /* Checks whether the specified answer contains at least one NSEC3 RR in the specified zone */ | |
314 | ||
315 | DNS_ANSWER_FOREACH(rr, answer) { | |
316 | const char *p; | |
317 | ||
318 | if (rr->key->type != DNS_TYPE_NSEC3) | |
319 | continue; | |
320 | ||
1c02e7ba | 321 | p = dns_resource_key_name(rr->key); |
e926785a LP |
322 | r = dns_name_parent(&p); |
323 | if (r < 0) | |
324 | return r; | |
325 | if (r == 0) | |
326 | continue; | |
327 | ||
328 | r = dns_name_equal(p, zone); | |
329 | if (r != 0) | |
330 | return r; | |
331 | } | |
332 | ||
333 | return false; | |
334 | } | |
335 | ||
fd009cd8 | 336 | int dns_answer_find_soa(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret, DnsAnswerFlags *flags) { |
81f7fc5e LP |
337 | DnsResourceRecord *rr, *soa = NULL; |
338 | DnsAnswerFlags rr_flags, soa_flags = 0; | |
29c1519e | 339 | int r; |
7e8e0422 | 340 | |
7e8e0422 | 341 | assert(key); |
7e8e0422 | 342 | |
0f05c387 LP |
343 | /* For a SOA record we can never find a matching SOA record */ |
344 | if (key->type == DNS_TYPE_SOA) | |
345 | return 0; | |
346 | ||
fd009cd8 | 347 | DNS_ANSWER_FOREACH_FLAGS(rr, rr_flags, a) { |
29c1519e LP |
348 | r = dns_resource_key_match_soa(key, rr->key); |
349 | if (r < 0) | |
350 | return r; | |
351 | if (r > 0) { | |
81f7fc5e LP |
352 | |
353 | if (soa) { | |
1c02e7ba | 354 | r = dns_name_endswith(dns_resource_key_name(rr->key), dns_resource_key_name(soa->key)); |
81f7fc5e LP |
355 | if (r < 0) |
356 | return r; | |
357 | if (r > 0) | |
358 | continue; | |
359 | } | |
360 | ||
361 | soa = rr; | |
362 | soa_flags = rr_flags; | |
7e8e0422 LP |
363 | } |
364 | } | |
365 | ||
81f7fc5e LP |
366 | if (!soa) |
367 | return 0; | |
368 | ||
369 | if (ret) | |
370 | *ret = soa; | |
371 | if (flags) | |
372 | *flags = soa_flags; | |
373 | ||
374 | return 1; | |
faa133f3 | 375 | } |
934e9b10 | 376 | |
105e1512 | 377 | int dns_answer_find_cname_or_dname(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret, DnsAnswerFlags *flags) { |
5d27351f | 378 | DnsResourceRecord *rr; |
105e1512 | 379 | DnsAnswerFlags rr_flags; |
29c1519e | 380 | int r; |
5d27351f TG |
381 | |
382 | assert(key); | |
383 | ||
5d27351f | 384 | /* For a {C,D}NAME record we can never find a matching {C,D}NAME record */ |
6b2f7093 | 385 | if (!dns_type_may_redirect(key->type)) |
5d27351f TG |
386 | return 0; |
387 | ||
105e1512 | 388 | DNS_ANSWER_FOREACH_FLAGS(rr, rr_flags, a) { |
29c1519e LP |
389 | r = dns_resource_key_match_cname_or_dname(key, rr->key, NULL); |
390 | if (r < 0) | |
391 | return r; | |
392 | if (r > 0) { | |
5d27351f TG |
393 | if (ret) |
394 | *ret = rr; | |
105e1512 LP |
395 | if (flags) |
396 | *flags = rr_flags; | |
5d27351f TG |
397 | return 1; |
398 | } | |
399 | } | |
400 | ||
401 | return 0; | |
402 | } | |
403 | ||
547973de LP |
404 | int dns_answer_merge(DnsAnswer *a, DnsAnswer *b, DnsAnswer **ret) { |
405 | _cleanup_(dns_answer_unrefp) DnsAnswer *k = NULL; | |
406 | int r; | |
407 | ||
408 | assert(ret); | |
409 | ||
410 | if (dns_answer_size(a) <= 0) { | |
411 | *ret = dns_answer_ref(b); | |
412 | return 0; | |
413 | } | |
414 | ||
415 | if (dns_answer_size(b) <= 0) { | |
416 | *ret = dns_answer_ref(a); | |
417 | return 0; | |
418 | } | |
419 | ||
420 | k = dns_answer_new(a->n_rrs + b->n_rrs); | |
421 | if (!k) | |
422 | return -ENOMEM; | |
423 | ||
424 | r = dns_answer_add_raw_all(k, a); | |
425 | if (r < 0) | |
426 | return r; | |
427 | ||
428 | r = dns_answer_add_all(k, b); | |
429 | if (r < 0) | |
430 | return r; | |
431 | ||
1cc6c93a | 432 | *ret = TAKE_PTR(k); |
547973de LP |
433 | |
434 | return 0; | |
435 | } | |
436 | ||
437 | int dns_answer_extend(DnsAnswer **a, DnsAnswer *b) { | |
438 | DnsAnswer *merged; | |
439 | int r; | |
440 | ||
441 | assert(a); | |
442 | ||
443 | r = dns_answer_merge(*a, b, &merged); | |
444 | if (r < 0) | |
445 | return r; | |
446 | ||
447 | dns_answer_unref(*a); | |
448 | *a = merged; | |
449 | ||
450 | return 0; | |
451 | } | |
452 | ||
453 | int dns_answer_remove_by_key(DnsAnswer **a, const DnsResourceKey *key) { | |
454 | bool found = false, other = false; | |
455 | DnsResourceRecord *rr; | |
da6053d0 | 456 | size_t i; |
934e9b10 LP |
457 | int r; |
458 | ||
547973de LP |
459 | assert(a); |
460 | assert(key); | |
934e9b10 | 461 | |
547973de | 462 | /* Remove all entries matching the specified key from *a */ |
934e9b10 | 463 | |
547973de LP |
464 | DNS_ANSWER_FOREACH(rr, *a) { |
465 | r = dns_resource_key_equal(rr->key, key); | |
466 | if (r < 0) | |
467 | return r; | |
468 | if (r > 0) | |
469 | found = true; | |
470 | else | |
471 | other = true; | |
472 | ||
473 | if (found && other) | |
474 | break; | |
475 | } | |
476 | ||
477 | if (!found) | |
478 | return 0; | |
479 | ||
480 | if (!other) { | |
481 | *a = dns_answer_unref(*a); /* Return NULL for the empty answer */ | |
482 | return 1; | |
934e9b10 LP |
483 | } |
484 | ||
547973de LP |
485 | if ((*a)->n_ref > 1) { |
486 | _cleanup_(dns_answer_unrefp) DnsAnswer *copy = NULL; | |
105e1512 | 487 | DnsAnswerFlags flags; |
547973de LP |
488 | int ifindex; |
489 | ||
490 | copy = dns_answer_new((*a)->n_rrs); | |
491 | if (!copy) | |
492 | return -ENOMEM; | |
493 | ||
105e1512 | 494 | DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, *a) { |
547973de | 495 | r = dns_resource_key_equal(rr->key, key); |
934e9b10 | 496 | if (r < 0) |
547973de LP |
497 | return r; |
498 | if (r > 0) | |
499 | continue; | |
500 | ||
105e1512 | 501 | r = dns_answer_add_raw(copy, rr, ifindex, flags); |
547973de LP |
502 | if (r < 0) |
503 | return r; | |
934e9b10 | 504 | } |
547973de LP |
505 | |
506 | dns_answer_unref(*a); | |
1cc6c93a | 507 | *a = TAKE_PTR(copy); |
547973de LP |
508 | |
509 | return 1; | |
510 | } | |
511 | ||
512 | /* Only a single reference, edit in-place */ | |
513 | ||
514 | i = 0; | |
515 | for (;;) { | |
516 | if (i >= (*a)->n_rrs) | |
517 | break; | |
518 | ||
519 | r = dns_resource_key_equal((*a)->items[i].rr->key, key); | |
520 | if (r < 0) | |
521 | return r; | |
522 | if (r > 0) { | |
523 | /* Kill this entry */ | |
524 | ||
525 | dns_resource_record_unref((*a)->items[i].rr); | |
526 | memmove((*a)->items + i, (*a)->items + i + 1, sizeof(DnsAnswerItem) * ((*a)->n_rrs - i - 1)); | |
313cefa1 | 527 | (*a)->n_rrs--; |
547973de LP |
528 | continue; |
529 | ||
530 | } else | |
531 | /* Keep this entry */ | |
532 | i++; | |
934e9b10 LP |
533 | } |
534 | ||
547973de LP |
535 | return 1; |
536 | } | |
537 | ||
0c857028 LP |
538 | int dns_answer_remove_by_rr(DnsAnswer **a, DnsResourceRecord *rm) { |
539 | bool found = false, other = false; | |
540 | DnsResourceRecord *rr; | |
da6053d0 | 541 | size_t i; |
0c857028 LP |
542 | int r; |
543 | ||
544 | assert(a); | |
545 | assert(rm); | |
546 | ||
547 | /* Remove all entries matching the specified RR from *a */ | |
548 | ||
549 | DNS_ANSWER_FOREACH(rr, *a) { | |
550 | r = dns_resource_record_equal(rr, rm); | |
551 | if (r < 0) | |
552 | return r; | |
553 | if (r > 0) | |
554 | found = true; | |
555 | else | |
556 | other = true; | |
557 | ||
558 | if (found && other) | |
559 | break; | |
560 | } | |
561 | ||
562 | if (!found) | |
563 | return 0; | |
564 | ||
565 | if (!other) { | |
566 | *a = dns_answer_unref(*a); /* Return NULL for the empty answer */ | |
567 | return 1; | |
568 | } | |
569 | ||
570 | if ((*a)->n_ref > 1) { | |
571 | _cleanup_(dns_answer_unrefp) DnsAnswer *copy = NULL; | |
572 | DnsAnswerFlags flags; | |
573 | int ifindex; | |
574 | ||
575 | copy = dns_answer_new((*a)->n_rrs); | |
576 | if (!copy) | |
577 | return -ENOMEM; | |
578 | ||
579 | DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, *a) { | |
580 | r = dns_resource_record_equal(rr, rm); | |
581 | if (r < 0) | |
582 | return r; | |
583 | if (r > 0) | |
584 | continue; | |
585 | ||
586 | r = dns_answer_add_raw(copy, rr, ifindex, flags); | |
587 | if (r < 0) | |
588 | return r; | |
589 | } | |
590 | ||
591 | dns_answer_unref(*a); | |
1cc6c93a | 592 | *a = TAKE_PTR(copy); |
0c857028 LP |
593 | |
594 | return 1; | |
595 | } | |
596 | ||
597 | /* Only a single reference, edit in-place */ | |
598 | ||
599 | i = 0; | |
600 | for (;;) { | |
601 | if (i >= (*a)->n_rrs) | |
602 | break; | |
603 | ||
604 | r = dns_resource_record_equal((*a)->items[i].rr, rm); | |
605 | if (r < 0) | |
606 | return r; | |
607 | if (r > 0) { | |
608 | /* Kill this entry */ | |
609 | ||
610 | dns_resource_record_unref((*a)->items[i].rr); | |
611 | memmove((*a)->items + i, (*a)->items + i + 1, sizeof(DnsAnswerItem) * ((*a)->n_rrs - i - 1)); | |
313cefa1 | 612 | (*a)->n_rrs--; |
0c857028 LP |
613 | continue; |
614 | ||
615 | } else | |
616 | /* Keep this entry */ | |
617 | i++; | |
618 | } | |
619 | ||
620 | return 1; | |
621 | } | |
622 | ||
105e1512 | 623 | int dns_answer_copy_by_key(DnsAnswer **a, DnsAnswer *source, const DnsResourceKey *key, DnsAnswerFlags or_flags) { |
547973de LP |
624 | DnsResourceRecord *rr_source; |
625 | int ifindex_source, r; | |
105e1512 | 626 | DnsAnswerFlags flags_source; |
547973de LP |
627 | |
628 | assert(a); | |
629 | assert(key); | |
630 | ||
631 | /* Copy all RRs matching the specified key from source into *a */ | |
632 | ||
105e1512 | 633 | DNS_ANSWER_FOREACH_FULL(rr_source, ifindex_source, flags_source, source) { |
547973de LP |
634 | |
635 | r = dns_resource_key_equal(rr_source->key, key); | |
636 | if (r < 0) | |
637 | return r; | |
638 | if (r == 0) | |
639 | continue; | |
640 | ||
641 | /* Make space for at least one entry */ | |
642 | r = dns_answer_reserve_or_clone(a, 1); | |
643 | if (r < 0) | |
644 | return r; | |
934e9b10 | 645 | |
105e1512 | 646 | r = dns_answer_add(*a, rr_source, ifindex_source, flags_source|or_flags); |
547973de LP |
647 | if (r < 0) |
648 | return r; | |
649 | } | |
650 | ||
651 | return 0; | |
934e9b10 | 652 | } |
af93291c | 653 | |
105e1512 LP |
654 | int dns_answer_move_by_key(DnsAnswer **to, DnsAnswer **from, const DnsResourceKey *key, DnsAnswerFlags or_flags) { |
655 | int r; | |
656 | ||
657 | assert(to); | |
658 | assert(from); | |
659 | assert(key); | |
660 | ||
661 | r = dns_answer_copy_by_key(to, *from, key, or_flags); | |
662 | if (r < 0) | |
663 | return r; | |
664 | ||
665 | return dns_answer_remove_by_key(from, key); | |
666 | } | |
667 | ||
af93291c | 668 | void dns_answer_order_by_scope(DnsAnswer *a, bool prefer_link_local) { |
78c6a153 | 669 | DnsAnswerItem *items; |
da6053d0 | 670 | size_t i, start, end; |
78c6a153 LP |
671 | |
672 | if (!a) | |
673 | return; | |
af93291c LP |
674 | |
675 | if (a->n_rrs <= 1) | |
676 | return; | |
677 | ||
678 | start = 0; | |
679 | end = a->n_rrs-1; | |
680 | ||
681 | /* RFC 4795, Section 2.6 suggests we should order entries | |
682 | * depending on whether the sender is a link-local address. */ | |
683 | ||
78c6a153 | 684 | items = newa(DnsAnswerItem, a->n_rrs); |
af93291c LP |
685 | for (i = 0; i < a->n_rrs; i++) { |
686 | ||
78c6a153 LP |
687 | if (a->items[i].rr->key->class == DNS_CLASS_IN && |
688 | ((a->items[i].rr->key->type == DNS_TYPE_A && in_addr_is_link_local(AF_INET, (union in_addr_union*) &a->items[i].rr->a.in_addr) != prefer_link_local) || | |
689 | (a->items[i].rr->key->type == DNS_TYPE_AAAA && in_addr_is_link_local(AF_INET6, (union in_addr_union*) &a->items[i].rr->aaaa.in6_addr) != prefer_link_local))) | |
61233823 | 690 | /* Order address records that are not preferred to the end of the array */ |
78c6a153 | 691 | items[end--] = a->items[i]; |
af93291c LP |
692 | else |
693 | /* Order all other records to the beginning of the array */ | |
78c6a153 | 694 | items[start++] = a->items[i]; |
af93291c LP |
695 | } |
696 | ||
697 | assert(start == end+1); | |
78c6a153 LP |
698 | memcpy(a->items, items, sizeof(DnsAnswerItem) * a->n_rrs); |
699 | } | |
700 | ||
da6053d0 | 701 | int dns_answer_reserve(DnsAnswer **a, size_t n_free) { |
78c6a153 LP |
702 | DnsAnswer *n; |
703 | ||
2f763887 LP |
704 | assert(a); |
705 | ||
78c6a153 LP |
706 | if (n_free <= 0) |
707 | return 0; | |
708 | ||
709 | if (*a) { | |
da6053d0 | 710 | size_t ns; |
78c6a153 LP |
711 | |
712 | if ((*a)->n_ref > 1) | |
713 | return -EBUSY; | |
714 | ||
715 | ns = (*a)->n_rrs + n_free; | |
716 | ||
717 | if ((*a)->n_allocated >= ns) | |
718 | return 0; | |
719 | ||
2f763887 LP |
720 | /* Allocate more than we need */ |
721 | ns *= 2; | |
722 | ||
78c6a153 LP |
723 | n = realloc(*a, offsetof(DnsAnswer, items) + sizeof(DnsAnswerItem) * ns); |
724 | if (!n) | |
725 | return -ENOMEM; | |
726 | ||
727 | n->n_allocated = ns; | |
728 | } else { | |
729 | n = dns_answer_new(n_free); | |
730 | if (!n) | |
731 | return -ENOMEM; | |
732 | } | |
733 | ||
734 | *a = n; | |
735 | return 0; | |
af93291c | 736 | } |
547973de | 737 | |
da6053d0 | 738 | int dns_answer_reserve_or_clone(DnsAnswer **a, size_t n_free) { |
547973de LP |
739 | _cleanup_(dns_answer_unrefp) DnsAnswer *n = NULL; |
740 | int r; | |
741 | ||
742 | assert(a); | |
743 | ||
744 | /* Tries to extend the DnsAnswer object. And if that's not | |
96d49011 | 745 | * possible, since we are not the sole owner, then allocate a |
547973de LP |
746 | * new, appropriately sized one. Either way, after this call |
747 | * the object will only have a single reference, and has room | |
748 | * for at least the specified number of RRs. */ | |
749 | ||
750 | r = dns_answer_reserve(a, n_free); | |
751 | if (r != -EBUSY) | |
752 | return r; | |
753 | ||
754 | assert(*a); | |
755 | ||
756 | n = dns_answer_new(((*a)->n_rrs + n_free) * 2); | |
757 | if (!n) | |
758 | return -ENOMEM; | |
759 | ||
760 | r = dns_answer_add_raw_all(n, *a); | |
761 | if (r < 0) | |
762 | return r; | |
763 | ||
764 | dns_answer_unref(*a); | |
1cc6c93a | 765 | *a = TAKE_PTR(n); |
547973de LP |
766 | |
767 | return 0; | |
768 | } | |
26156910 LP |
769 | |
770 | void dns_answer_dump(DnsAnswer *answer, FILE *f) { | |
771 | DnsResourceRecord *rr; | |
772 | DnsAnswerFlags flags; | |
7b50eb2e | 773 | int ifindex; |
26156910 LP |
774 | |
775 | if (!f) | |
776 | f = stdout; | |
777 | ||
778 | DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, answer) { | |
7b50eb2e | 779 | const char *t; |
26156910 LP |
780 | |
781 | fputc('\t', f); | |
782 | ||
7b50eb2e LP |
783 | t = dns_resource_record_to_string(rr); |
784 | if (!t) { | |
26156910 LP |
785 | log_oom(); |
786 | continue; | |
787 | } | |
788 | ||
789 | fputs(t, f); | |
790 | ||
791 | if (ifindex != 0 || flags & (DNS_ANSWER_AUTHENTICATED|DNS_ANSWER_CACHEABLE|DNS_ANSWER_SHARED_OWNER)) | |
792 | fputs("\t;", f); | |
793 | ||
794 | if (ifindex != 0) | |
795 | printf(" ifindex=%i", ifindex); | |
796 | if (flags & DNS_ANSWER_AUTHENTICATED) | |
797 | fputs(" authenticated", f); | |
798 | if (flags & DNS_ANSWER_CACHEABLE) | |
799 | fputs(" cachable", f); | |
800 | if (flags & DNS_ANSWER_SHARED_OWNER) | |
801 | fputs(" shared-owner", f); | |
802 | ||
803 | fputc('\n', f); | |
804 | } | |
805 | } | |
43e6779a LP |
806 | |
807 | bool dns_answer_has_dname_for_cname(DnsAnswer *a, DnsResourceRecord *cname) { | |
808 | DnsResourceRecord *rr; | |
809 | int r; | |
810 | ||
811 | assert(cname); | |
812 | ||
813 | /* Checks whether the answer contains a DNAME record that indicates that the specified CNAME record is | |
814 | * synthesized from it */ | |
815 | ||
816 | if (cname->key->type != DNS_TYPE_CNAME) | |
817 | return 0; | |
818 | ||
819 | DNS_ANSWER_FOREACH(rr, a) { | |
820 | _cleanup_free_ char *n = NULL; | |
821 | ||
822 | if (rr->key->type != DNS_TYPE_DNAME) | |
823 | continue; | |
824 | if (rr->key->class != cname->key->class) | |
825 | continue; | |
826 | ||
1c02e7ba | 827 | r = dns_name_change_suffix(cname->cname.name, rr->dname.name, dns_resource_key_name(rr->key), &n); |
43e6779a LP |
828 | if (r < 0) |
829 | return r; | |
830 | if (r == 0) | |
831 | continue; | |
832 | ||
1c02e7ba | 833 | r = dns_name_equal(n, dns_resource_key_name(cname->key)); |
43e6779a LP |
834 | if (r < 0) |
835 | return r; | |
836 | if (r > 0) | |
837 | return 1; | |
838 | ||
839 | } | |
840 | ||
841 | return 0; | |
842 | } |