1 /***
2 This file is part of avahi.
3
4 avahi is free software; you can redistribute it and/or modify it
5 under the terms of the GNU Lesser General Public License as
6 published by the Free Software Foundation; either version 2.1 of the
7 License, or (at your option) any later version.
8
9 avahi is distributed in the hope that it will be useful, but WITHOUT
10 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
12 Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with avahi; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
17 USA.
18 ***/
19
20 #ifdef HAVE_CONFIG_H
21 #include <config.h>
22 #endif
23
24 #include <string.h>
25 #include <stdio.h>
26 #include <sys/types.h>
27 #include <sys/socket.h>
28 #include <arpa/inet.h>
29 #include <assert.h>
30
31 #include <avahi-common/domain.h>
32 #include <avahi-common/malloc.h>
33 #include <avahi-common/defs.h>
34
35 #include "rr.h"
36 #include "log.h"
37 #include "util.h"
38 #include "hashmap.h"
39 #include "domain-util.h"
40 #include "rr-util.h"
41 #include "addr-util.h"
42
avahi_key_new(const char * name,uint16_t class,uint16_t type)43 AvahiKey *avahi_key_new(const char *name, uint16_t class, uint16_t type) {
44 AvahiKey *k;
45 assert(name);
46
47 if (!(k = avahi_new(AvahiKey, 1))) {
48 avahi_log_error("avahi_new() failed.");
49 return NULL;
50 }
51
52 if (!(k->name = avahi_normalize_name_strdup(name))) {
53 avahi_log_error("avahi_normalize_name() failed.");
54 avahi_free(k);
55 return NULL;
56 }
57
58 k->ref = 1;
59 k->clazz = class;
60 k->type = type;
61
62 return k;
63 }
64
avahi_key_new_cname(AvahiKey * key)65 AvahiKey *avahi_key_new_cname(AvahiKey *key) {
66 assert(key);
67
68 if (key->clazz != AVAHI_DNS_CLASS_IN)
69 return NULL;
70
71 if (key->type == AVAHI_DNS_TYPE_CNAME)
72 return NULL;
73
74 return avahi_key_new(key->name, key->clazz, AVAHI_DNS_TYPE_CNAME);
75 }
76
avahi_key_ref(AvahiKey * k)77 AvahiKey *avahi_key_ref(AvahiKey *k) {
78 assert(k);
79 assert(k->ref >= 1);
80
81 k->ref++;
82
83 return k;
84 }
85
avahi_key_unref(AvahiKey * k)86 void avahi_key_unref(AvahiKey *k) {
87 assert(k);
88 assert(k->ref >= 1);
89
90 if ((--k->ref) <= 0) {
91 avahi_free(k->name);
92 avahi_free(k);
93 }
94 }
95
avahi_record_new(AvahiKey * k,uint32_t ttl)96 AvahiRecord *avahi_record_new(AvahiKey *k, uint32_t ttl) {
97 AvahiRecord *r;
98
99 assert(k);
100
101 if (!(r = avahi_new(AvahiRecord, 1))) {
102 avahi_log_error("avahi_new() failed.");
103 return NULL;
104 }
105
106 r->ref = 1;
107 r->key = avahi_key_ref(k);
108
109 memset(&r->data, 0, sizeof(r->data));
110
111 r->ttl = ttl != (uint32_t) -1 ? ttl : AVAHI_DEFAULT_TTL;
112
113 return r;
114 }
115
avahi_record_new_full(const char * name,uint16_t class,uint16_t type,uint32_t ttl)116 AvahiRecord *avahi_record_new_full(const char *name, uint16_t class, uint16_t type, uint32_t ttl) {
117 AvahiRecord *r;
118 AvahiKey *k;
119
120 assert(name);
121
122 if (!(k = avahi_key_new(name, class, type))) {
123 avahi_log_error("avahi_key_new() failed.");
124 return NULL;
125 }
126
127 r = avahi_record_new(k, ttl);
128 avahi_key_unref(k);
129
130 if (!r) {
131 avahi_log_error("avahi_record_new() failed.");
132 return NULL;
133 }
134
135 return r;
136 }
137
avahi_record_ref(AvahiRecord * r)138 AvahiRecord *avahi_record_ref(AvahiRecord *r) {
139 assert(r);
140 assert(r->ref >= 1);
141
142 r->ref++;
143 return r;
144 }
145
avahi_record_unref(AvahiRecord * r)146 void avahi_record_unref(AvahiRecord *r) {
147 assert(r);
148 assert(r->ref >= 1);
149
150 if ((--r->ref) <= 0) {
151 switch (r->key->type) {
152
153 case AVAHI_DNS_TYPE_SRV:
154 avahi_free(r->data.srv.name);
155 break;
156
157 case AVAHI_DNS_TYPE_PTR:
158 case AVAHI_DNS_TYPE_CNAME:
159 case AVAHI_DNS_TYPE_NS:
160 avahi_free(r->data.ptr.name);
161 break;
162
163 case AVAHI_DNS_TYPE_HINFO:
164 avahi_free(r->data.hinfo.cpu);
165 avahi_free(r->data.hinfo.os);
166 break;
167
168 case AVAHI_DNS_TYPE_TXT:
169 avahi_string_list_free(r->data.txt.string_list);
170 break;
171
172 case AVAHI_DNS_TYPE_A:
173 case AVAHI_DNS_TYPE_AAAA:
174 break;
175
176 default:
177 avahi_free(r->data.generic.data);
178 }
179
180 avahi_key_unref(r->key);
181 avahi_free(r);
182 }
183 }
184
avahi_dns_class_to_string(uint16_t class)185 const char *avahi_dns_class_to_string(uint16_t class) {
186 if (class & AVAHI_DNS_CACHE_FLUSH)
187 return "FLUSH";
188
189 switch (class) {
190 case AVAHI_DNS_CLASS_IN:
191 return "IN";
192 case AVAHI_DNS_CLASS_ANY:
193 return "ANY";
194 default:
195 return NULL;
196 }
197 }
198
avahi_dns_type_to_string(uint16_t type)199 const char *avahi_dns_type_to_string(uint16_t type) {
200 switch (type) {
201 case AVAHI_DNS_TYPE_CNAME:
202 return "CNAME";
203 case AVAHI_DNS_TYPE_A:
204 return "A";
205 case AVAHI_DNS_TYPE_AAAA:
206 return "AAAA";
207 case AVAHI_DNS_TYPE_PTR:
208 return "PTR";
209 case AVAHI_DNS_TYPE_HINFO:
210 return "HINFO";
211 case AVAHI_DNS_TYPE_TXT:
212 return "TXT";
213 case AVAHI_DNS_TYPE_SRV:
214 return "SRV";
215 case AVAHI_DNS_TYPE_ANY:
216 return "ANY";
217 case AVAHI_DNS_TYPE_SOA:
218 return "SOA";
219 case AVAHI_DNS_TYPE_NS:
220 return "NS";
221 default:
222 return NULL;
223 }
224 }
225
avahi_key_to_string(const AvahiKey * k)226 char *avahi_key_to_string(const AvahiKey *k) {
227 char class[16], type[16];
228 const char *c, *t;
229
230 assert(k);
231 assert(k->ref >= 1);
232
233 /* According to RFC3597 */
234
235 if (!(c = avahi_dns_class_to_string(k->clazz))) {
236 snprintf(class, sizeof(class), "CLASS%u", k->clazz);
237 c = class;
238 }
239
240 if (!(t = avahi_dns_type_to_string(k->type))) {
241 snprintf(type, sizeof(type), "TYPE%u", k->type);
242 t = type;
243 }
244
245 return avahi_strdup_printf("%s\t%s\t%s", k->name, c, t);
246 }
247
avahi_record_to_string(const AvahiRecord * r)248 char *avahi_record_to_string(const AvahiRecord *r) {
249 char *p, *s;
250 char buf[1024], *t = NULL, *d = NULL;
251
252 assert(r);
253 assert(r->ref >= 1);
254
255 switch (r->key->type) {
256 case AVAHI_DNS_TYPE_A:
257 inet_ntop(AF_INET, &r->data.a.address.address, t = buf, sizeof(buf));
258 break;
259
260 case AVAHI_DNS_TYPE_AAAA:
261 inet_ntop(AF_INET6, &r->data.aaaa.address.address, t = buf, sizeof(buf));
262 break;
263
264 case AVAHI_DNS_TYPE_PTR:
265 case AVAHI_DNS_TYPE_CNAME:
266 case AVAHI_DNS_TYPE_NS:
267
268 t = r->data.ptr.name;
269 break;
270
271 case AVAHI_DNS_TYPE_TXT:
272 t = d = avahi_string_list_to_string(r->data.txt.string_list);
273 break;
274
275 case AVAHI_DNS_TYPE_HINFO:
276
277 snprintf(t = buf, sizeof(buf), "\"%s\" \"%s\"", r->data.hinfo.cpu, r->data.hinfo.os);
278 break;
279
280 case AVAHI_DNS_TYPE_SRV:
281
282 snprintf(t = buf, sizeof(buf), "%u %u %u %s",
283 r->data.srv.priority,
284 r->data.srv.weight,
285 r->data.srv.port,
286 r->data.srv.name);
287
288 break;
289
290 default: {
291
292 uint8_t *c;
293 uint16_t n;
294 int i;
295 char *e;
296
297 /* According to RFC3597 */
298
299 snprintf(t = buf, sizeof(buf), "\\# %u", r->data.generic.size);
300
301 e = strchr(t, 0);
302
303 for (c = r->data.generic.data, n = r->data.generic.size, i = 0;
304 n > 0 && i < 20;
305 c ++, n --, i++) {
306
307 sprintf(e, " %02X", *c);
308 e = strchr(e, 0);
309 }
310
311 break;
312 }
313 }
314
315 p = avahi_key_to_string(r->key);
316 s = avahi_strdup_printf("%s %s ; ttl=%u", p, t, r->ttl);
317 avahi_free(p);
318 avahi_free(d);
319
320 return s;
321 }
322
avahi_key_equal(const AvahiKey * a,const AvahiKey * b)323 int avahi_key_equal(const AvahiKey *a, const AvahiKey *b) {
324 assert(a);
325 assert(b);
326
327 if (a == b)
328 return 1;
329
330 return avahi_domain_equal(a->name, b->name) &&
331 a->type == b->type &&
332 a->clazz == b->clazz;
333 }
334
avahi_key_pattern_match(const AvahiKey * pattern,const AvahiKey * k)335 int avahi_key_pattern_match(const AvahiKey *pattern, const AvahiKey *k) {
336 assert(pattern);
337 assert(k);
338
339 assert(!avahi_key_is_pattern(k));
340
341 if (pattern == k)
342 return 1;
343
344 return avahi_domain_equal(pattern->name, k->name) &&
345 (pattern->type == k->type || pattern->type == AVAHI_DNS_TYPE_ANY) &&
346 (pattern->clazz == k->clazz || pattern->clazz == AVAHI_DNS_CLASS_ANY);
347 }
348
avahi_key_is_pattern(const AvahiKey * k)349 int avahi_key_is_pattern(const AvahiKey *k) {
350 assert(k);
351
352 return
353 k->type == AVAHI_DNS_TYPE_ANY ||
354 k->clazz == AVAHI_DNS_CLASS_ANY;
355 }
356
avahi_key_hash(const AvahiKey * k)357 unsigned avahi_key_hash(const AvahiKey *k) {
358 assert(k);
359
360 return
361 avahi_domain_hash(k->name) +
362 k->type +
363 k->clazz;
364 }
365
rdata_equal(const AvahiRecord * a,const AvahiRecord * b)366 static int rdata_equal(const AvahiRecord *a, const AvahiRecord *b) {
367 assert(a);
368 assert(b);
369 assert(a->key->type == b->key->type);
370
371 switch (a->key->type) {
372 case AVAHI_DNS_TYPE_SRV:
373 return
374 a->data.srv.priority == b->data.srv.priority &&
375 a->data.srv.weight == b->data.srv.weight &&
376 a->data.srv.port == b->data.srv.port &&
377 avahi_domain_equal(a->data.srv.name, b->data.srv.name);
378
379 case AVAHI_DNS_TYPE_PTR:
380 case AVAHI_DNS_TYPE_CNAME:
381 case AVAHI_DNS_TYPE_NS:
382 return avahi_domain_equal(a->data.ptr.name, b->data.ptr.name);
383
384 case AVAHI_DNS_TYPE_HINFO:
385 return
386 !strcmp(a->data.hinfo.cpu, b->data.hinfo.cpu) &&
387 !strcmp(a->data.hinfo.os, b->data.hinfo.os);
388
389 case AVAHI_DNS_TYPE_TXT:
390 return avahi_string_list_equal(a->data.txt.string_list, b->data.txt.string_list);
391
392 case AVAHI_DNS_TYPE_A:
393 return memcmp(&a->data.a.address, &b->data.a.address, sizeof(AvahiIPv4Address)) == 0;
394
395 case AVAHI_DNS_TYPE_AAAA:
396 return memcmp(&a->data.aaaa.address, &b->data.aaaa.address, sizeof(AvahiIPv6Address)) == 0;
397
398 default:
399 return a->data.generic.size == b->data.generic.size &&
400 (a->data.generic.size == 0 || memcmp(a->data.generic.data, b->data.generic.data, a->data.generic.size) == 0);
401 }
402
403 }
404
avahi_record_equal_no_ttl(const AvahiRecord * a,const AvahiRecord * b)405 int avahi_record_equal_no_ttl(const AvahiRecord *a, const AvahiRecord *b) {
406 assert(a);
407 assert(b);
408
409 if (a == b)
410 return 1;
411
412 return
413 avahi_key_equal(a->key, b->key) &&
414 rdata_equal(a, b);
415 }
416
417
avahi_record_copy(AvahiRecord * r)418 AvahiRecord *avahi_record_copy(AvahiRecord *r) {
419 AvahiRecord *copy;
420
421 if (!(copy = avahi_new(AvahiRecord, 1))) {
422 avahi_log_error("avahi_new() failed.");
423 return NULL;
424 }
425
426 copy->ref = 1;
427 copy->key = avahi_key_ref(r->key);
428 copy->ttl = r->ttl;
429
430 switch (r->key->type) {
431 case AVAHI_DNS_TYPE_PTR:
432 case AVAHI_DNS_TYPE_CNAME:
433 case AVAHI_DNS_TYPE_NS:
434 if (!(copy->data.ptr.name = avahi_strdup(r->data.ptr.name)))
435 goto fail;
436 break;
437
438 case AVAHI_DNS_TYPE_SRV:
439 copy->data.srv.priority = r->data.srv.priority;
440 copy->data.srv.weight = r->data.srv.weight;
441 copy->data.srv.port = r->data.srv.port;
442 if (!(copy->data.srv.name = avahi_strdup(r->data.srv.name)))
443 goto fail;
444 break;
445
446 case AVAHI_DNS_TYPE_HINFO:
447 if (!(copy->data.hinfo.os = avahi_strdup(r->data.hinfo.os)))
448 goto fail;
449
450 if (!(copy->data.hinfo.cpu = avahi_strdup(r->data.hinfo.cpu))) {
451 avahi_free(r->data.hinfo.os);
452 goto fail;
453 }
454 break;
455
456 case AVAHI_DNS_TYPE_TXT:
457 copy->data.txt.string_list = avahi_string_list_copy(r->data.txt.string_list);
458 break;
459
460 case AVAHI_DNS_TYPE_A:
461 copy->data.a.address = r->data.a.address;
462 break;
463
464 case AVAHI_DNS_TYPE_AAAA:
465 copy->data.aaaa.address = r->data.aaaa.address;
466 break;
467
468 default:
469 if (!(copy->data.generic.data = avahi_memdup(r->data.generic.data, r->data.generic.size)))
470 goto fail;
471 copy->data.generic.size = r->data.generic.size;
472 break;
473
474 }
475
476 return copy;
477
478 fail:
479 avahi_log_error("Failed to allocate memory");
480
481 avahi_key_unref(copy->key);
482 avahi_free(copy);
483
484 return NULL;
485 }
486
487
avahi_key_get_estimate_size(AvahiKey * k)488 size_t avahi_key_get_estimate_size(AvahiKey *k) {
489 assert(k);
490
491 return strlen(k->name)+1+4;
492 }
493
avahi_record_get_estimate_size(AvahiRecord * r)494 size_t avahi_record_get_estimate_size(AvahiRecord *r) {
495 size_t n;
496 assert(r);
497
498 n = avahi_key_get_estimate_size(r->key) + 4 + 2;
499
500 switch (r->key->type) {
501 case AVAHI_DNS_TYPE_PTR:
502 case AVAHI_DNS_TYPE_CNAME:
503 case AVAHI_DNS_TYPE_NS:
504 n += strlen(r->data.ptr.name) + 1;
505 break;
506
507 case AVAHI_DNS_TYPE_SRV:
508 n += 6 + strlen(r->data.srv.name) + 1;
509 break;
510
511 case AVAHI_DNS_TYPE_HINFO:
512 n += strlen(r->data.hinfo.os) + 1 + strlen(r->data.hinfo.cpu) + 1;
513 break;
514
515 case AVAHI_DNS_TYPE_TXT:
516 n += avahi_string_list_serialize(r->data.txt.string_list, NULL, 0);
517 break;
518
519 case AVAHI_DNS_TYPE_A:
520 n += sizeof(AvahiIPv4Address);
521 break;
522
523 case AVAHI_DNS_TYPE_AAAA:
524 n += sizeof(AvahiIPv6Address);
525 break;
526
527 default:
528 n += r->data.generic.size;
529 }
530
531 return n;
532 }
533
lexicographical_memcmp(const void * a,size_t al,const void * b,size_t bl)534 static int lexicographical_memcmp(const void* a, size_t al, const void* b, size_t bl) {
535 size_t c;
536 int ret;
537
538 assert(a);
539 assert(b);
540
541 c = al < bl ? al : bl;
542 if ((ret = memcmp(a, b, c)))
543 return ret;
544
545 if (al == bl)
546 return 0;
547 else
548 return al == c ? 1 : -1;
549 }
550
uint16_cmp(uint16_t a,uint16_t b)551 static int uint16_cmp(uint16_t a, uint16_t b) {
552 return a == b ? 0 : (a < b ? -1 : 1);
553 }
554
avahi_record_lexicographical_compare(AvahiRecord * a,AvahiRecord * b)555 int avahi_record_lexicographical_compare(AvahiRecord *a, AvahiRecord *b) {
556 int r;
557 /* char *t1, *t2; */
558
559 assert(a);
560 assert(b);
561
562 /* t1 = avahi_record_to_string(a); */
563 /* t2 = avahi_record_to_string(b); */
564 /* g_message("lexicocmp: %s %s", t1, t2); */
565 /* avahi_free(t1); */
566 /* avahi_free(t2); */
567
568 if (a == b)
569 return 0;
570
571 if ((r = uint16_cmp(a->key->clazz, b->key->clazz)) ||
572 (r = uint16_cmp(a->key->type, b->key->type)))
573 return r;
574
575 switch (a->key->type) {
576
577 case AVAHI_DNS_TYPE_PTR:
578 case AVAHI_DNS_TYPE_CNAME:
579 case AVAHI_DNS_TYPE_NS:
580 return avahi_binary_domain_cmp(a->data.ptr.name, b->data.ptr.name);
581
582 case AVAHI_DNS_TYPE_SRV: {
583 if ((r = uint16_cmp(a->data.srv.priority, b->data.srv.priority)) == 0 &&
584 (r = uint16_cmp(a->data.srv.weight, b->data.srv.weight)) == 0 &&
585 (r = uint16_cmp(a->data.srv.port, b->data.srv.port)) == 0)
586 r = avahi_binary_domain_cmp(a->data.srv.name, b->data.srv.name);
587
588 return r;
589 }
590
591 case AVAHI_DNS_TYPE_HINFO: {
592
593 if ((r = strcmp(a->data.hinfo.cpu, b->data.hinfo.cpu)) ||
594 (r = strcmp(a->data.hinfo.os, b->data.hinfo.os)))
595 return r;
596
597 return 0;
598
599 }
600
601 case AVAHI_DNS_TYPE_TXT: {
602
603 uint8_t *ma = NULL, *mb = NULL;
604 size_t asize, bsize;
605
606 asize = avahi_string_list_serialize(a->data.txt.string_list, NULL, 0);
607 bsize = avahi_string_list_serialize(b->data.txt.string_list, NULL, 0);
608
609 if (asize > 0 && !(ma = avahi_new(uint8_t, asize)))
610 goto fail;
611
612 if (bsize > 0 && !(mb = avahi_new(uint8_t, bsize))) {
613 avahi_free(ma);
614 goto fail;
615 }
616
617 avahi_string_list_serialize(a->data.txt.string_list, ma, asize);
618 avahi_string_list_serialize(b->data.txt.string_list, mb, bsize);
619
620 if (asize && bsize)
621 r = lexicographical_memcmp(ma, asize, mb, bsize);
622 else if (asize && !bsize)
623 r = 1;
624 else if (!asize && bsize)
625 r = -1;
626 else
627 r = 0;
628
629 avahi_free(ma);
630 avahi_free(mb);
631
632 return r;
633 }
634
635 case AVAHI_DNS_TYPE_A:
636 return memcmp(&a->data.a.address, &b->data.a.address, sizeof(AvahiIPv4Address));
637
638 case AVAHI_DNS_TYPE_AAAA:
639 return memcmp(&a->data.aaaa.address, &b->data.aaaa.address, sizeof(AvahiIPv6Address));
640
641 default:
642 return lexicographical_memcmp(a->data.generic.data, a->data.generic.size,
643 b->data.generic.data, b->data.generic.size);
644 }
645
646
647 fail:
648 avahi_log_error(__FILE__": Out of memory");
649 return -1; /* or whatever ... */
650 }
651
avahi_record_is_goodbye(AvahiRecord * r)652 int avahi_record_is_goodbye(AvahiRecord *r) {
653 assert(r);
654
655 return r->ttl == 0;
656 }
657
avahi_key_is_valid(AvahiKey * k)658 int avahi_key_is_valid(AvahiKey *k) {
659 assert(k);
660
661 if (!avahi_is_valid_domain_name(k->name))
662 return 0;
663
664 return 1;
665 }
666
avahi_record_is_valid(AvahiRecord * r)667 int avahi_record_is_valid(AvahiRecord *r) {
668 assert(r);
669
670 if (!avahi_key_is_valid(r->key))
671 return 0;
672
673 switch (r->key->type) {
674
675 case AVAHI_DNS_TYPE_PTR:
676 case AVAHI_DNS_TYPE_CNAME:
677 case AVAHI_DNS_TYPE_NS:
678 return avahi_is_valid_domain_name(r->data.ptr.name);
679
680 case AVAHI_DNS_TYPE_SRV:
681 return avahi_is_valid_domain_name(r->data.srv.name);
682
683 case AVAHI_DNS_TYPE_HINFO:
684 return
685 strlen(r->data.hinfo.os) <= 255 &&
686 strlen(r->data.hinfo.cpu) <= 255;
687
688 case AVAHI_DNS_TYPE_TXT: {
689
690 AvahiStringList *strlst;
691
692 for (strlst = r->data.txt.string_list; strlst; strlst = strlst->next)
693 if (strlst->size > 255 || strlst->size <= 0)
694 return 0;
695
696 return 1;
697 }
698 }
699
700 return 1;
701 }
702
get_address(const AvahiRecord * r,AvahiAddress * a)703 static AvahiAddress *get_address(const AvahiRecord *r, AvahiAddress *a) {
704 assert(r);
705
706 switch (r->key->type) {
707 case AVAHI_DNS_TYPE_A:
708 a->proto = AVAHI_PROTO_INET;
709 a->data.ipv4 = r->data.a.address;
710 break;
711
712 case AVAHI_DNS_TYPE_AAAA:
713 a->proto = AVAHI_PROTO_INET6;
714 a->data.ipv6 = r->data.aaaa.address;
715 break;
716
717 default:
718 return NULL;
719 }
720
721 return a;
722 }
723
avahi_record_is_link_local_address(const AvahiRecord * r)724 int avahi_record_is_link_local_address(const AvahiRecord *r) {
725 AvahiAddress a;
726
727 assert(r);
728
729 if (!get_address(r, &a))
730 return 0;
731
732 return avahi_address_is_link_local(&a);
733 }
734