1 /*
2 * packet.c
3 *
4 * dns packet implementation
5 *
6 * a Net::DNS like library for C
7 *
8 * (c) NLnet Labs, 2004-2006
9 *
10 * See the file LICENSE for the license
11 */
12
13 #include <ldns/config.h>
14
15 #include <ldns/ldns.h>
16
17 #include <strings.h>
18 #include <limits.h>
19
20 #ifdef HAVE_SSL
21 #include <openssl/rand.h>
22 #endif
23
24 /* Access functions
25 * do this as functions to get type checking
26 */
27
28 #define LDNS_EDNS_MASK_DO_BIT 0x8000
29
30 /* TODO defines for 3600 */
31 /* convert to and from numerical flag values */
32 ldns_lookup_table ldns_edns_flags[] = {
33 { 3600, "do"},
34 { 0, NULL}
35 };
36
37 /* read */
38 uint16_t
ldns_pkt_id(const ldns_pkt * packet)39 ldns_pkt_id(const ldns_pkt *packet)
40 {
41 return packet->_header->_id;
42 }
43
44 bool
ldns_pkt_qr(const ldns_pkt * packet)45 ldns_pkt_qr(const ldns_pkt *packet)
46 {
47 return packet->_header->_qr;
48 }
49
50 bool
ldns_pkt_aa(const ldns_pkt * packet)51 ldns_pkt_aa(const ldns_pkt *packet)
52 {
53 return packet->_header->_aa;
54 }
55
56 bool
ldns_pkt_tc(const ldns_pkt * packet)57 ldns_pkt_tc(const ldns_pkt *packet)
58 {
59 return packet->_header->_tc;
60 }
61
62 bool
ldns_pkt_rd(const ldns_pkt * packet)63 ldns_pkt_rd(const ldns_pkt *packet)
64 {
65 return packet->_header->_rd;
66 }
67
68 bool
ldns_pkt_cd(const ldns_pkt * packet)69 ldns_pkt_cd(const ldns_pkt *packet)
70 {
71 return packet->_header->_cd;
72 }
73
74 bool
ldns_pkt_ra(const ldns_pkt * packet)75 ldns_pkt_ra(const ldns_pkt *packet)
76 {
77 return packet->_header->_ra;
78 }
79
80 bool
ldns_pkt_ad(const ldns_pkt * packet)81 ldns_pkt_ad(const ldns_pkt *packet)
82 {
83 return packet->_header->_ad;
84 }
85
86 ldns_pkt_opcode
ldns_pkt_get_opcode(const ldns_pkt * packet)87 ldns_pkt_get_opcode(const ldns_pkt *packet)
88 {
89 return packet->_header->_opcode;
90 }
91
92 ldns_pkt_rcode
ldns_pkt_get_rcode(const ldns_pkt * packet)93 ldns_pkt_get_rcode(const ldns_pkt *packet)
94 {
95 return packet->_header->_rcode;
96 }
97
98 uint16_t
ldns_pkt_qdcount(const ldns_pkt * packet)99 ldns_pkt_qdcount(const ldns_pkt *packet)
100 {
101 return packet->_header->_qdcount;
102 }
103
104 uint16_t
ldns_pkt_ancount(const ldns_pkt * packet)105 ldns_pkt_ancount(const ldns_pkt *packet)
106 {
107 return packet->_header->_ancount;
108 }
109
110 uint16_t
ldns_pkt_nscount(const ldns_pkt * packet)111 ldns_pkt_nscount(const ldns_pkt *packet)
112 {
113 return packet->_header->_nscount;
114 }
115
116 uint16_t
ldns_pkt_arcount(const ldns_pkt * packet)117 ldns_pkt_arcount(const ldns_pkt *packet)
118 {
119 return packet->_header->_arcount;
120 }
121
122 ldns_rr_list *
ldns_pkt_question(const ldns_pkt * packet)123 ldns_pkt_question(const ldns_pkt *packet)
124 {
125 return packet->_question;
126 }
127
128 ldns_rr_list *
ldns_pkt_answer(const ldns_pkt * packet)129 ldns_pkt_answer(const ldns_pkt *packet)
130 {
131 return packet->_answer;
132 }
133
134 ldns_rr_list *
ldns_pkt_authority(const ldns_pkt * packet)135 ldns_pkt_authority(const ldns_pkt *packet)
136 {
137 return packet->_authority;
138 }
139
140 ldns_rr_list *
ldns_pkt_additional(const ldns_pkt * packet)141 ldns_pkt_additional(const ldns_pkt *packet)
142 {
143 return packet->_additional;
144 }
145
146 /* return ALL section concatenated */
147 ldns_rr_list *
ldns_pkt_all(const ldns_pkt * packet)148 ldns_pkt_all(const ldns_pkt *packet)
149 {
150 ldns_rr_list *all, *prev_all;
151
152 all = ldns_rr_list_cat_clone(
153 ldns_pkt_question(packet),
154 ldns_pkt_answer(packet));
155 prev_all = all;
156 all = ldns_rr_list_cat_clone(all,
157 ldns_pkt_authority(packet));
158 ldns_rr_list_deep_free(prev_all);
159 prev_all = all;
160 all = ldns_rr_list_cat_clone(all,
161 ldns_pkt_additional(packet));
162 ldns_rr_list_deep_free(prev_all);
163 return all;
164 }
165
166 ldns_rr_list *
ldns_pkt_all_noquestion(const ldns_pkt * packet)167 ldns_pkt_all_noquestion(const ldns_pkt *packet)
168 {
169 ldns_rr_list *all, *all2;
170
171 all = ldns_rr_list_cat_clone(
172 ldns_pkt_answer(packet),
173 ldns_pkt_authority(packet));
174 all2 = ldns_rr_list_cat_clone(all,
175 ldns_pkt_additional(packet));
176
177 ldns_rr_list_deep_free(all);
178 return all2;
179 }
180
181 size_t
ldns_pkt_size(const ldns_pkt * packet)182 ldns_pkt_size(const ldns_pkt *packet)
183 {
184 return packet->_size;
185 }
186
187 uint32_t
ldns_pkt_querytime(const ldns_pkt * packet)188 ldns_pkt_querytime(const ldns_pkt *packet)
189 {
190 return packet->_querytime;
191 }
192
193 ldns_rdf *
ldns_pkt_answerfrom(const ldns_pkt * packet)194 ldns_pkt_answerfrom(const ldns_pkt *packet)
195 {
196 return packet->_answerfrom;
197 }
198
199 struct timeval
ldns_pkt_timestamp(const ldns_pkt * packet)200 ldns_pkt_timestamp(const ldns_pkt *packet)
201 {
202 return packet->timestamp;
203 }
204
205 uint16_t
ldns_pkt_edns_udp_size(const ldns_pkt * packet)206 ldns_pkt_edns_udp_size(const ldns_pkt *packet)
207 {
208 return packet->_edns_udp_size;
209 }
210
211 uint8_t
ldns_pkt_edns_extended_rcode(const ldns_pkt * packet)212 ldns_pkt_edns_extended_rcode(const ldns_pkt *packet)
213 {
214 return packet->_edns_extended_rcode;
215 }
216
217 uint8_t
ldns_pkt_edns_version(const ldns_pkt * packet)218 ldns_pkt_edns_version(const ldns_pkt *packet)
219 {
220 return packet->_edns_version;
221 }
222
223 uint16_t
ldns_pkt_edns_z(const ldns_pkt * packet)224 ldns_pkt_edns_z(const ldns_pkt *packet)
225 {
226 return packet->_edns_z;
227 }
228
229 bool
ldns_pkt_edns_do(const ldns_pkt * packet)230 ldns_pkt_edns_do(const ldns_pkt *packet)
231 {
232 return (packet->_edns_z & LDNS_EDNS_MASK_DO_BIT);
233 }
234
235 void
ldns_pkt_set_edns_do(ldns_pkt * packet,bool value)236 ldns_pkt_set_edns_do(ldns_pkt *packet, bool value)
237 {
238 if (value) {
239 packet->_edns_z = packet->_edns_z | LDNS_EDNS_MASK_DO_BIT;
240 } else {
241 packet->_edns_z = packet->_edns_z & ~LDNS_EDNS_MASK_DO_BIT;
242 }
243 }
244
245 ldns_rdf *
ldns_pkt_edns_data(const ldns_pkt * packet)246 ldns_pkt_edns_data(const ldns_pkt *packet)
247 {
248 return packet->_edns_data;
249 }
250
251 /* return only those rr that share the ownername */
252 ldns_rr_list *
ldns_pkt_rr_list_by_name(ldns_pkt * packet,ldns_rdf * ownername,ldns_pkt_section sec)253 ldns_pkt_rr_list_by_name(ldns_pkt *packet,
254 ldns_rdf *ownername,
255 ldns_pkt_section sec)
256 {
257 ldns_rr_list *rrs;
258 ldns_rr_list *ret;
259 uint16_t i;
260
261 if (!packet) {
262 return NULL;
263 }
264
265 rrs = ldns_pkt_get_section_clone(packet, sec);
266 ret = NULL;
267
268 for(i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
269 if (ldns_dname_compare(ldns_rr_owner(
270 ldns_rr_list_rr(rrs, i)),
271 ownername) == 0) {
272 /* owner names match */
273 if (ret == NULL) {
274 ret = ldns_rr_list_new();
275 }
276 ldns_rr_list_push_rr(ret, ldns_rr_list_rr(rrs, i));
277 }
278 }
279 return ret;
280 }
281
282 /* return only those rr that share a type */
283 ldns_rr_list *
ldns_pkt_rr_list_by_type(const ldns_pkt * packet,ldns_rr_type type,ldns_pkt_section sec)284 ldns_pkt_rr_list_by_type(const ldns_pkt *packet,
285 ldns_rr_type type,
286 ldns_pkt_section sec)
287 {
288 ldns_rr_list *rrs;
289 ldns_rr_list *new;
290 uint16_t i;
291
292 if(!packet) {
293 return NULL;
294 }
295
296 rrs = ldns_pkt_get_section_clone(packet, sec);
297 new = ldns_rr_list_new();
298
299 for(i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
300 if (type == ldns_rr_get_type(ldns_rr_list_rr(rrs, i))) {
301 /* types match */
302 ldns_rr_list_push_rr(new,
303 ldns_rr_clone(
304 ldns_rr_list_rr(rrs, i))
305 );
306 }
307 }
308 ldns_rr_list_deep_free(rrs);
309
310 if (ldns_rr_list_rr_count(new) == 0) {
311 ldns_rr_list_free(new);
312 return NULL;
313 } else {
314 return new;
315 }
316 }
317
318 /* return only those rrs that share name and type */
319 ldns_rr_list *
ldns_pkt_rr_list_by_name_and_type(const ldns_pkt * packet,const ldns_rdf * ownername,ldns_rr_type type,ldns_pkt_section sec)320 ldns_pkt_rr_list_by_name_and_type(const ldns_pkt *packet,
321 const ldns_rdf *ownername,
322 ldns_rr_type type,
323 ldns_pkt_section sec)
324 {
325 ldns_rr_list *rrs;
326 ldns_rr_list *new;
327 ldns_rr_list *ret;
328 uint16_t i;
329
330 if(!packet) {
331 return NULL;
332 }
333
334 rrs = ldns_pkt_get_section_clone(packet, sec);
335 new = ldns_rr_list_new();
336 ret = NULL;
337
338 for(i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
339 if (type == ldns_rr_get_type(ldns_rr_list_rr(rrs, i)) &&
340 ldns_dname_compare(ldns_rr_owner(ldns_rr_list_rr(rrs, i)),
341 ownername
342 ) == 0
343 ) {
344 /* types match */
345 ldns_rr_list_push_rr(new, ldns_rr_clone(ldns_rr_list_rr(rrs, i)));
346 ret = new;
347 }
348 }
349 ldns_rr_list_deep_free(rrs);
350 if (!ret) {
351 ldns_rr_list_free(new);
352 }
353 return ret;
354 }
355
356 bool
ldns_pkt_rr(ldns_pkt * pkt,ldns_pkt_section sec,ldns_rr * rr)357 ldns_pkt_rr(ldns_pkt *pkt, ldns_pkt_section sec, ldns_rr *rr)
358 {
359 bool result = false;
360
361 switch (sec) {
362 case LDNS_SECTION_QUESTION:
363 return ldns_rr_list_contains_rr(ldns_pkt_question(pkt), rr);
364 case LDNS_SECTION_ANSWER:
365 return ldns_rr_list_contains_rr(ldns_pkt_answer(pkt), rr);
366 case LDNS_SECTION_AUTHORITY:
367 return ldns_rr_list_contains_rr(ldns_pkt_authority(pkt), rr);
368 case LDNS_SECTION_ADDITIONAL:
369 return ldns_rr_list_contains_rr(ldns_pkt_additional(pkt), rr);
370 case LDNS_SECTION_ANY:
371 result = ldns_rr_list_contains_rr(ldns_pkt_question(pkt), rr);
372 case LDNS_SECTION_ANY_NOQUESTION:
373 result = result
374 || ldns_rr_list_contains_rr(ldns_pkt_answer(pkt), rr)
375 || ldns_rr_list_contains_rr(ldns_pkt_authority(pkt), rr)
376 || ldns_rr_list_contains_rr(ldns_pkt_additional(pkt), rr);
377 }
378
379 return result;
380 }
381
382 uint16_t
ldns_pkt_section_count(const ldns_pkt * packet,ldns_pkt_section s)383 ldns_pkt_section_count(const ldns_pkt *packet, ldns_pkt_section s)
384 {
385 switch(s) {
386 case LDNS_SECTION_QUESTION:
387 return ldns_pkt_qdcount(packet);
388 case LDNS_SECTION_ANSWER:
389 return ldns_pkt_ancount(packet);
390 case LDNS_SECTION_AUTHORITY:
391 return ldns_pkt_nscount(packet);
392 case LDNS_SECTION_ADDITIONAL:
393 return ldns_pkt_arcount(packet);
394 case LDNS_SECTION_ANY:
395 return ldns_pkt_qdcount(packet) +
396 ldns_pkt_ancount(packet) +
397 ldns_pkt_nscount(packet) +
398 ldns_pkt_arcount(packet);
399 case LDNS_SECTION_ANY_NOQUESTION:
400 return ldns_pkt_ancount(packet) +
401 ldns_pkt_nscount(packet) +
402 ldns_pkt_arcount(packet);
403 default:
404 return 0;
405 }
406 }
407
408 bool
ldns_pkt_empty(ldns_pkt * p)409 ldns_pkt_empty(ldns_pkt *p)
410 {
411 if (!p) {
412 return true; /* NULL is empty? */
413 }
414 if (ldns_pkt_section_count(p, LDNS_SECTION_ANY) > 0) {
415 return false;
416 } else {
417 return true;
418 }
419 }
420
421
422 ldns_rr_list *
ldns_pkt_get_section_clone(const ldns_pkt * packet,ldns_pkt_section s)423 ldns_pkt_get_section_clone(const ldns_pkt *packet, ldns_pkt_section s)
424 {
425 switch(s) {
426 case LDNS_SECTION_QUESTION:
427 return ldns_rr_list_clone(ldns_pkt_question(packet));
428 case LDNS_SECTION_ANSWER:
429 return ldns_rr_list_clone(ldns_pkt_answer(packet));
430 case LDNS_SECTION_AUTHORITY:
431 return ldns_rr_list_clone(ldns_pkt_authority(packet));
432 case LDNS_SECTION_ADDITIONAL:
433 return ldns_rr_list_clone(ldns_pkt_additional(packet));
434 case LDNS_SECTION_ANY:
435 /* these are already clones */
436 return ldns_pkt_all(packet);
437 case LDNS_SECTION_ANY_NOQUESTION:
438 return ldns_pkt_all_noquestion(packet);
439 default:
440 return NULL;
441 }
442 }
443
ldns_pkt_tsig(const ldns_pkt * pkt)444 ldns_rr *ldns_pkt_tsig(const ldns_pkt *pkt) {
445 return pkt->_tsig_rr;
446 }
447
448 /* write */
449 void
ldns_pkt_set_id(ldns_pkt * packet,uint16_t id)450 ldns_pkt_set_id(ldns_pkt *packet, uint16_t id)
451 {
452 packet->_header->_id = id;
453 }
454
455 void
ldns_pkt_set_random_id(ldns_pkt * packet)456 ldns_pkt_set_random_id(ldns_pkt *packet)
457 {
458 uint16_t rid = ldns_get_random();
459 ldns_pkt_set_id(packet, rid);
460 }
461
462
463 void
ldns_pkt_set_qr(ldns_pkt * packet,bool qr)464 ldns_pkt_set_qr(ldns_pkt *packet, bool qr)
465 {
466 packet->_header->_qr = qr;
467 }
468
469 void
ldns_pkt_set_aa(ldns_pkt * packet,bool aa)470 ldns_pkt_set_aa(ldns_pkt *packet, bool aa)
471 {
472 packet->_header->_aa = aa;
473 }
474
475 void
ldns_pkt_set_tc(ldns_pkt * packet,bool tc)476 ldns_pkt_set_tc(ldns_pkt *packet, bool tc)
477 {
478 packet->_header->_tc = tc;
479 }
480
481 void
ldns_pkt_set_rd(ldns_pkt * packet,bool rd)482 ldns_pkt_set_rd(ldns_pkt *packet, bool rd)
483 {
484 packet->_header->_rd = rd;
485 }
486
487 void
ldns_pkt_set_additional(ldns_pkt * p,ldns_rr_list * rr)488 ldns_pkt_set_additional(ldns_pkt *p, ldns_rr_list *rr)
489 {
490 p->_additional = rr;
491 }
492
493 void
ldns_pkt_set_question(ldns_pkt * p,ldns_rr_list * rr)494 ldns_pkt_set_question(ldns_pkt *p, ldns_rr_list *rr)
495 {
496 p->_question = rr;
497 }
498
499 void
ldns_pkt_set_answer(ldns_pkt * p,ldns_rr_list * rr)500 ldns_pkt_set_answer(ldns_pkt *p, ldns_rr_list *rr)
501 {
502 p->_answer = rr;
503 }
504
505 void
ldns_pkt_set_authority(ldns_pkt * p,ldns_rr_list * rr)506 ldns_pkt_set_authority(ldns_pkt *p, ldns_rr_list *rr)
507 {
508 p->_authority = rr;
509 }
510
511 void
ldns_pkt_set_cd(ldns_pkt * packet,bool cd)512 ldns_pkt_set_cd(ldns_pkt *packet, bool cd)
513 {
514 packet->_header->_cd = cd;
515 }
516
517 void
ldns_pkt_set_ra(ldns_pkt * packet,bool ra)518 ldns_pkt_set_ra(ldns_pkt *packet, bool ra)
519 {
520 packet->_header->_ra = ra;
521 }
522
523 void
ldns_pkt_set_ad(ldns_pkt * packet,bool ad)524 ldns_pkt_set_ad(ldns_pkt *packet, bool ad)
525 {
526 packet->_header->_ad = ad;
527 }
528
529 void
ldns_pkt_set_opcode(ldns_pkt * packet,ldns_pkt_opcode opcode)530 ldns_pkt_set_opcode(ldns_pkt *packet, ldns_pkt_opcode opcode)
531 {
532 packet->_header->_opcode = opcode;
533 }
534
535 void
ldns_pkt_set_rcode(ldns_pkt * packet,uint8_t rcode)536 ldns_pkt_set_rcode(ldns_pkt *packet, uint8_t rcode)
537 {
538 packet->_header->_rcode = rcode;
539 }
540
541 void
ldns_pkt_set_qdcount(ldns_pkt * packet,uint16_t qdcount)542 ldns_pkt_set_qdcount(ldns_pkt *packet, uint16_t qdcount)
543 {
544 packet->_header->_qdcount = qdcount;
545 }
546
547 void
ldns_pkt_set_ancount(ldns_pkt * packet,uint16_t ancount)548 ldns_pkt_set_ancount(ldns_pkt *packet, uint16_t ancount)
549 {
550 packet->_header->_ancount = ancount;
551 }
552
553 void
ldns_pkt_set_nscount(ldns_pkt * packet,uint16_t nscount)554 ldns_pkt_set_nscount(ldns_pkt *packet, uint16_t nscount)
555 {
556 packet->_header->_nscount = nscount;
557 }
558
559 void
ldns_pkt_set_arcount(ldns_pkt * packet,uint16_t arcount)560 ldns_pkt_set_arcount(ldns_pkt *packet, uint16_t arcount)
561 {
562 packet->_header->_arcount = arcount;
563 }
564
565 void
ldns_pkt_set_querytime(ldns_pkt * packet,uint32_t time)566 ldns_pkt_set_querytime(ldns_pkt *packet, uint32_t time)
567 {
568 packet->_querytime = time;
569 }
570
571 void
ldns_pkt_set_answerfrom(ldns_pkt * packet,ldns_rdf * answerfrom)572 ldns_pkt_set_answerfrom(ldns_pkt *packet, ldns_rdf *answerfrom)
573 {
574 packet->_answerfrom = answerfrom;
575 }
576
577 void
ldns_pkt_set_timestamp(ldns_pkt * packet,struct timeval timeval)578 ldns_pkt_set_timestamp(ldns_pkt *packet, struct timeval timeval)
579 {
580 packet->timestamp.tv_sec = timeval.tv_sec;
581 packet->timestamp.tv_usec = timeval.tv_usec;
582 }
583
584 void
ldns_pkt_set_size(ldns_pkt * packet,size_t s)585 ldns_pkt_set_size(ldns_pkt *packet, size_t s)
586 {
587 packet->_size = s;
588 }
589
590 void
ldns_pkt_set_edns_udp_size(ldns_pkt * packet,uint16_t s)591 ldns_pkt_set_edns_udp_size(ldns_pkt *packet, uint16_t s)
592 {
593 packet->_edns_udp_size = s;
594 }
595
596 void
ldns_pkt_set_edns_extended_rcode(ldns_pkt * packet,uint8_t c)597 ldns_pkt_set_edns_extended_rcode(ldns_pkt *packet, uint8_t c)
598 {
599 packet->_edns_extended_rcode = c;
600 }
601
602 void
ldns_pkt_set_edns_version(ldns_pkt * packet,uint8_t v)603 ldns_pkt_set_edns_version(ldns_pkt *packet, uint8_t v)
604 {
605 packet->_edns_version = v;
606 }
607
608 void
ldns_pkt_set_edns_z(ldns_pkt * packet,uint16_t z)609 ldns_pkt_set_edns_z(ldns_pkt *packet, uint16_t z)
610 {
611 packet->_edns_z = z;
612 }
613
614 void
ldns_pkt_set_edns_data(ldns_pkt * packet,ldns_rdf * data)615 ldns_pkt_set_edns_data(ldns_pkt *packet, ldns_rdf *data)
616 {
617 packet->_edns_data = data;
618 }
619
620 void
ldns_pkt_set_section_count(ldns_pkt * packet,ldns_pkt_section s,uint16_t count)621 ldns_pkt_set_section_count(ldns_pkt *packet, ldns_pkt_section s, uint16_t count)
622 {
623 switch(s) {
624 case LDNS_SECTION_QUESTION:
625 ldns_pkt_set_qdcount(packet, count);
626 break;
627 case LDNS_SECTION_ANSWER:
628 ldns_pkt_set_ancount(packet, count);
629 break;
630 case LDNS_SECTION_AUTHORITY:
631 ldns_pkt_set_nscount(packet, count);
632 break;
633 case LDNS_SECTION_ADDITIONAL:
634 ldns_pkt_set_arcount(packet, count);
635 break;
636 case LDNS_SECTION_ANY:
637 case LDNS_SECTION_ANY_NOQUESTION:
638 break;
639 }
640 }
641
ldns_pkt_set_tsig(ldns_pkt * pkt,ldns_rr * rr)642 void ldns_pkt_set_tsig(ldns_pkt *pkt, ldns_rr *rr)
643 {
644 pkt->_tsig_rr = rr;
645 }
646
647 bool
ldns_pkt_push_rr(ldns_pkt * packet,ldns_pkt_section section,ldns_rr * rr)648 ldns_pkt_push_rr(ldns_pkt *packet, ldns_pkt_section section, ldns_rr *rr)
649 {
650 switch(section) {
651 case LDNS_SECTION_QUESTION:
652 if (!ldns_rr_list_push_rr(ldns_pkt_question(packet), rr)) {
653 return false;
654 }
655 ldns_pkt_set_qdcount(packet, ldns_pkt_qdcount(packet) + 1);
656 break;
657 case LDNS_SECTION_ANSWER:
658 if (!ldns_rr_list_push_rr(ldns_pkt_answer(packet), rr)) {
659 return false;
660 }
661 ldns_pkt_set_ancount(packet, ldns_pkt_ancount(packet) + 1);
662 break;
663 case LDNS_SECTION_AUTHORITY:
664 if (!ldns_rr_list_push_rr(ldns_pkt_authority(packet), rr)) {
665 return false;
666 }
667 ldns_pkt_set_nscount(packet, ldns_pkt_nscount(packet) + 1);
668 break;
669 case LDNS_SECTION_ADDITIONAL:
670 if (!ldns_rr_list_push_rr(ldns_pkt_additional(packet), rr)) {
671 return false;
672 }
673 ldns_pkt_set_arcount(packet, ldns_pkt_arcount(packet) + 1);
674 break;
675 case LDNS_SECTION_ANY:
676 case LDNS_SECTION_ANY_NOQUESTION:
677 /* shouldn't this error? */
678 break;
679 }
680 return true;
681 }
682
683 bool
ldns_pkt_safe_push_rr(ldns_pkt * pkt,ldns_pkt_section sec,ldns_rr * rr)684 ldns_pkt_safe_push_rr(ldns_pkt *pkt, ldns_pkt_section sec, ldns_rr *rr)
685 {
686
687 /* check to see if its there */
688 if (ldns_pkt_rr(pkt, sec, rr)) {
689 /* already there */
690 return false;
691 }
692 return ldns_pkt_push_rr(pkt, sec, rr);
693 }
694
695 bool
ldns_pkt_push_rr_list(ldns_pkt * p,ldns_pkt_section s,ldns_rr_list * list)696 ldns_pkt_push_rr_list(ldns_pkt *p, ldns_pkt_section s, ldns_rr_list *list)
697 {
698 size_t i;
699 for(i = 0; i < ldns_rr_list_rr_count(list); i++) {
700 if (!ldns_pkt_push_rr(p, s, ldns_rr_list_rr(list, i))) {
701 return false;
702 }
703 }
704 return true;
705 }
706
707 bool
ldns_pkt_safe_push_rr_list(ldns_pkt * p,ldns_pkt_section s,ldns_rr_list * list)708 ldns_pkt_safe_push_rr_list(ldns_pkt *p, ldns_pkt_section s, ldns_rr_list *list)
709 {
710 size_t i;
711 for(i = 0; i < ldns_rr_list_rr_count(list); i++) {
712 if (!ldns_pkt_safe_push_rr(p, s, ldns_rr_list_rr(list, i))) {
713 return false;
714 }
715 }
716 return true;
717 }
718
719 bool
ldns_pkt_edns(const ldns_pkt * pkt)720 ldns_pkt_edns(const ldns_pkt *pkt) {
721 return (ldns_pkt_edns_udp_size(pkt) > 0 ||
722 ldns_pkt_edns_extended_rcode(pkt) > 0 ||
723 ldns_pkt_edns_data(pkt) ||
724 ldns_pkt_edns_do(pkt)
725 );
726 }
727
728
729 /* Create/destroy/convert functions
730 */
731 ldns_pkt *
ldns_pkt_new(void)732 ldns_pkt_new(void)
733 {
734 ldns_pkt *packet;
735 packet = LDNS_MALLOC(ldns_pkt);
736 if (!packet) {
737 return NULL;
738 }
739
740 packet->_header = LDNS_MALLOC(ldns_hdr);
741 if (!packet->_header) {
742 LDNS_FREE(packet);
743 return NULL;
744 }
745
746 packet->_question = ldns_rr_list_new();
747 packet->_answer = ldns_rr_list_new();
748 packet->_authority = ldns_rr_list_new();
749 packet->_additional = ldns_rr_list_new();
750
751 /* default everything to false */
752 ldns_pkt_set_qr(packet, false);
753 ldns_pkt_set_aa(packet, false);
754 ldns_pkt_set_tc(packet, false);
755 ldns_pkt_set_rd(packet, false);
756 ldns_pkt_set_ra(packet, false);
757 ldns_pkt_set_ad(packet, false);
758 ldns_pkt_set_cd(packet, false);
759
760 ldns_pkt_set_opcode(packet, LDNS_PACKET_QUERY);
761 ldns_pkt_set_rcode(packet, 0);
762 ldns_pkt_set_id(packet, 0);
763 ldns_pkt_set_size(packet, 0);
764 ldns_pkt_set_querytime(packet, 0);
765 memset(&packet->timestamp, 0, sizeof(packet->timestamp));
766 ldns_pkt_set_answerfrom(packet, NULL);
767 ldns_pkt_set_section_count(packet, LDNS_SECTION_QUESTION, 0);
768 ldns_pkt_set_section_count(packet, LDNS_SECTION_ANSWER, 0);
769 ldns_pkt_set_section_count(packet, LDNS_SECTION_AUTHORITY, 0);
770 ldns_pkt_set_section_count(packet, LDNS_SECTION_ADDITIONAL, 0);
771
772 ldns_pkt_set_edns_udp_size(packet, 0);
773 ldns_pkt_set_edns_extended_rcode(packet, 0);
774 ldns_pkt_set_edns_version(packet, 0);
775 ldns_pkt_set_edns_z(packet, 0);
776 ldns_pkt_set_edns_data(packet, NULL);
777
778 ldns_pkt_set_tsig(packet, NULL);
779
780 return packet;
781 }
782
783 void
ldns_pkt_free(ldns_pkt * packet)784 ldns_pkt_free(ldns_pkt *packet)
785 {
786 if (packet) {
787 LDNS_FREE(packet->_header);
788 ldns_rr_list_deep_free(packet->_question);
789 ldns_rr_list_deep_free(packet->_answer);
790 ldns_rr_list_deep_free(packet->_authority);
791 ldns_rr_list_deep_free(packet->_additional);
792 ldns_rr_free(packet->_tsig_rr);
793 ldns_rdf_deep_free(packet->_edns_data);
794 ldns_rdf_deep_free(packet->_answerfrom);
795 LDNS_FREE(packet);
796 }
797 }
798
799 bool
ldns_pkt_set_flags(ldns_pkt * packet,uint16_t flags)800 ldns_pkt_set_flags(ldns_pkt *packet, uint16_t flags)
801 {
802 if (!packet) {
803 return false;
804 }
805 if ((flags & LDNS_QR) == LDNS_QR) {
806 ldns_pkt_set_qr(packet, true);
807 }
808 if ((flags & LDNS_AA) == LDNS_AA) {
809 ldns_pkt_set_aa(packet, true);
810 }
811 if ((flags & LDNS_RD) == LDNS_RD) {
812 ldns_pkt_set_rd(packet, true);
813 }
814 if ((flags & LDNS_TC) == LDNS_TC) {
815 ldns_pkt_set_tc(packet, true);
816 }
817 if ((flags & LDNS_CD) == LDNS_CD) {
818 ldns_pkt_set_cd(packet, true);
819 }
820 if ((flags & LDNS_RA) == LDNS_RA) {
821 ldns_pkt_set_ra(packet, true);
822 }
823 if ((flags & LDNS_AD) == LDNS_AD) {
824 ldns_pkt_set_ad(packet, true);
825 }
826 return true;
827 }
828
829
830 static ldns_rr*
ldns_pkt_authsoa(ldns_rdf * rr_name,ldns_rr_class rr_class)831 ldns_pkt_authsoa(ldns_rdf* rr_name, ldns_rr_class rr_class)
832 {
833 ldns_rr* soa_rr = ldns_rr_new();
834 ldns_rdf *owner_rdf;
835 ldns_rdf *mname_rdf;
836 ldns_rdf *rname_rdf;
837 ldns_rdf *serial_rdf;
838 ldns_rdf *refresh_rdf;
839 ldns_rdf *retry_rdf;
840 ldns_rdf *expire_rdf;
841 ldns_rdf *minimum_rdf;
842
843 if (!soa_rr) {
844 return NULL;
845 }
846 owner_rdf = ldns_rdf_clone(rr_name);
847 if (!owner_rdf) {
848 ldns_rr_free(soa_rr);
849 return NULL;
850 }
851
852 ldns_rr_set_owner(soa_rr, owner_rdf);
853 ldns_rr_set_type(soa_rr, LDNS_RR_TYPE_SOA);
854 ldns_rr_set_class(soa_rr, rr_class);
855 ldns_rr_set_question(soa_rr, false);
856
857 if (ldns_str2rdf_dname(&mname_rdf, ".") != LDNS_STATUS_OK) {
858 ldns_rr_free(soa_rr);
859 return NULL;
860 } else {
861 ldns_rr_push_rdf(soa_rr, mname_rdf);
862 }
863 if (ldns_str2rdf_dname(&rname_rdf, ".") != LDNS_STATUS_OK) {
864 ldns_rr_free(soa_rr);
865 return NULL;
866 } else {
867 ldns_rr_push_rdf(soa_rr, rname_rdf);
868 }
869 serial_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
870 if (!serial_rdf) {
871 ldns_rr_free(soa_rr);
872 return NULL;
873 } else {
874 ldns_rr_push_rdf(soa_rr, serial_rdf);
875 }
876 refresh_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
877 if (!refresh_rdf) {
878 ldns_rr_free(soa_rr);
879 return NULL;
880 } else {
881 ldns_rr_push_rdf(soa_rr, refresh_rdf);
882 }
883 retry_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
884 if (!retry_rdf) {
885 ldns_rr_free(soa_rr);
886 return NULL;
887 } else {
888 ldns_rr_push_rdf(soa_rr, retry_rdf);
889 }
890 expire_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
891 if (!expire_rdf) {
892 ldns_rr_free(soa_rr);
893 return NULL;
894 } else {
895 ldns_rr_push_rdf(soa_rr, expire_rdf);
896 }
897 minimum_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
898 if (!minimum_rdf) {
899 ldns_rr_free(soa_rr);
900 return NULL;
901 } else {
902 ldns_rr_push_rdf(soa_rr, minimum_rdf);
903 }
904 return soa_rr;
905 }
906
907
908 static ldns_status
ldns_pkt_query_new_frm_str_internal(ldns_pkt ** p,const char * name,ldns_rr_type rr_type,ldns_rr_class rr_class,uint16_t flags,ldns_rr * authsoa_rr)909 ldns_pkt_query_new_frm_str_internal(ldns_pkt **p, const char *name,
910 ldns_rr_type rr_type, ldns_rr_class rr_class, uint16_t flags,
911 ldns_rr* authsoa_rr)
912 {
913 ldns_pkt *packet;
914 ldns_rr *question_rr;
915 ldns_rdf *name_rdf;
916
917 packet = ldns_pkt_new();
918 if (!packet) {
919 return LDNS_STATUS_MEM_ERR;
920 }
921
922 if (!ldns_pkt_set_flags(packet, flags)) {
923 return LDNS_STATUS_ERR;
924 }
925
926 question_rr = ldns_rr_new();
927 if (!question_rr) {
928 return LDNS_STATUS_MEM_ERR;
929 }
930
931 if (rr_type == 0) {
932 rr_type = LDNS_RR_TYPE_A;
933 }
934 if (rr_class == 0) {
935 rr_class = LDNS_RR_CLASS_IN;
936 }
937
938 if (ldns_str2rdf_dname(&name_rdf, name) == LDNS_STATUS_OK) {
939 ldns_rr_set_owner(question_rr, name_rdf);
940 ldns_rr_set_type(question_rr, rr_type);
941 ldns_rr_set_class(question_rr, rr_class);
942 ldns_rr_set_question(question_rr, true);
943
944 ldns_pkt_push_rr(packet, LDNS_SECTION_QUESTION, question_rr);
945 } else {
946 ldns_rr_free(question_rr);
947 ldns_pkt_free(packet);
948 return LDNS_STATUS_ERR;
949 }
950
951 if (authsoa_rr) {
952 ldns_pkt_push_rr(packet, LDNS_SECTION_AUTHORITY, authsoa_rr);
953 }
954
955 packet->_tsig_rr = NULL;
956 ldns_pkt_set_answerfrom(packet, NULL);
957 if (p) {
958 *p = packet;
959 return LDNS_STATUS_OK;
960 } else {
961 ldns_pkt_free(packet);
962 return LDNS_STATUS_NULL;
963 }
964 }
965
966 ldns_status
ldns_pkt_query_new_frm_str(ldns_pkt ** p,const char * name,ldns_rr_type rr_type,ldns_rr_class rr_class,uint16_t flags)967 ldns_pkt_query_new_frm_str(ldns_pkt **p, const char *name,
968 ldns_rr_type rr_type, ldns_rr_class rr_class, uint16_t flags)
969 {
970 return ldns_pkt_query_new_frm_str_internal(p, name, rr_type,
971 rr_class, flags, NULL);
972 }
973
974 ldns_status
ldns_pkt_ixfr_request_new_frm_str(ldns_pkt ** p,const char * name,ldns_rr_class rr_class,uint16_t flags,ldns_rr * soa)975 ldns_pkt_ixfr_request_new_frm_str(ldns_pkt **p, const char *name,
976 ldns_rr_class rr_class, uint16_t flags, ldns_rr *soa)
977 {
978 ldns_rr* authsoa_rr = soa;
979 if (!authsoa_rr) {
980 ldns_rdf *name_rdf;
981 if (ldns_str2rdf_dname(&name_rdf, name) == LDNS_STATUS_OK) {
982 authsoa_rr = ldns_pkt_authsoa(name_rdf, rr_class);
983 }
984 ldns_rdf_free(name_rdf);
985 }
986 return ldns_pkt_query_new_frm_str_internal(p, name, LDNS_RR_TYPE_IXFR,
987 rr_class, flags, authsoa_rr);
988 }
989
990 static ldns_pkt *
ldns_pkt_query_new_internal(ldns_rdf * rr_name,ldns_rr_type rr_type,ldns_rr_class rr_class,uint16_t flags,ldns_rr * authsoa_rr)991 ldns_pkt_query_new_internal(ldns_rdf *rr_name, ldns_rr_type rr_type,
992 ldns_rr_class rr_class, uint16_t flags, ldns_rr* authsoa_rr)
993 {
994 ldns_pkt *packet;
995 ldns_rr *question_rr;
996
997 packet = ldns_pkt_new();
998 if (!packet) {
999 return NULL;
1000 }
1001
1002 if (!ldns_pkt_set_flags(packet, flags)) {
1003 return NULL;
1004 }
1005
1006 question_rr = ldns_rr_new();
1007 if (!question_rr) {
1008 ldns_pkt_free(packet);
1009 return NULL;
1010 }
1011
1012 if (rr_type == 0) {
1013 rr_type = LDNS_RR_TYPE_A;
1014 }
1015 if (rr_class == 0) {
1016 rr_class = LDNS_RR_CLASS_IN;
1017 }
1018
1019 ldns_rr_set_owner(question_rr, rr_name);
1020 ldns_rr_set_type(question_rr, rr_type);
1021 ldns_rr_set_class(question_rr, rr_class);
1022 ldns_rr_set_question(question_rr, true);
1023 ldns_pkt_push_rr(packet, LDNS_SECTION_QUESTION, question_rr);
1024
1025 if (authsoa_rr) {
1026 ldns_pkt_push_rr(packet, LDNS_SECTION_AUTHORITY, authsoa_rr);
1027 }
1028
1029 packet->_tsig_rr = NULL;
1030 return packet;
1031 }
1032
1033 ldns_pkt *
ldns_pkt_query_new(ldns_rdf * rr_name,ldns_rr_type rr_type,ldns_rr_class rr_class,uint16_t flags)1034 ldns_pkt_query_new(ldns_rdf *rr_name, ldns_rr_type rr_type,
1035 ldns_rr_class rr_class, uint16_t flags)
1036 {
1037 return ldns_pkt_query_new_internal(rr_name, rr_type,
1038 rr_class, flags, NULL);
1039 }
1040
1041 ldns_pkt *
ldns_pkt_ixfr_request_new(ldns_rdf * rr_name,ldns_rr_class rr_class,uint16_t flags,ldns_rr * soa)1042 ldns_pkt_ixfr_request_new(ldns_rdf *rr_name, ldns_rr_class rr_class,
1043 uint16_t flags, ldns_rr* soa)
1044 {
1045 ldns_rr* authsoa_rr = soa;
1046 if (!authsoa_rr) {
1047 authsoa_rr = ldns_pkt_authsoa(rr_name, rr_class);
1048 }
1049 return ldns_pkt_query_new_internal(rr_name, LDNS_RR_TYPE_IXFR,
1050 rr_class, flags, authsoa_rr);
1051 }
1052
1053 ldns_pkt_type
ldns_pkt_reply_type(ldns_pkt * p)1054 ldns_pkt_reply_type(ldns_pkt *p)
1055 {
1056 ldns_rr_list *tmp;
1057
1058 if (!p) {
1059 return LDNS_PACKET_UNKNOWN;
1060 }
1061
1062 if (ldns_pkt_get_rcode(p) == LDNS_RCODE_NXDOMAIN) {
1063 return LDNS_PACKET_NXDOMAIN;
1064 }
1065
1066 if (ldns_pkt_ancount(p) == 0 && ldns_pkt_arcount(p) == 0
1067 && ldns_pkt_nscount(p) == 1) {
1068
1069 /* check for SOA */
1070 tmp = ldns_pkt_rr_list_by_type(p, LDNS_RR_TYPE_SOA,
1071 LDNS_SECTION_AUTHORITY);
1072 if (tmp) {
1073 ldns_rr_list_deep_free(tmp);
1074 return LDNS_PACKET_NODATA;
1075 } else {
1076 /* I have no idea ... */
1077 }
1078 }
1079
1080 if (ldns_pkt_ancount(p) == 0 && ldns_pkt_nscount(p) > 0) {
1081 tmp = ldns_pkt_rr_list_by_type(p, LDNS_RR_TYPE_NS,
1082 LDNS_SECTION_AUTHORITY);
1083 if (tmp) {
1084 /* there are nameservers here */
1085 ldns_rr_list_deep_free(tmp);
1086 return LDNS_PACKET_REFERRAL;
1087 } else {
1088 /* I have no idea */
1089 }
1090 ldns_rr_list_deep_free(tmp);
1091 }
1092
1093 /* if we cannot determine the packet type, we say it's an
1094 * answer...
1095 */
1096 return LDNS_PACKET_ANSWER;
1097 }
1098
1099 ldns_pkt *
ldns_pkt_clone(ldns_pkt * pkt)1100 ldns_pkt_clone(ldns_pkt *pkt)
1101 {
1102 ldns_pkt *new_pkt;
1103
1104 if (!pkt) {
1105 return NULL;
1106 }
1107 new_pkt = ldns_pkt_new();
1108
1109 ldns_pkt_set_id(new_pkt, ldns_pkt_id(pkt));
1110 ldns_pkt_set_qr(new_pkt, ldns_pkt_qr(pkt));
1111 ldns_pkt_set_aa(new_pkt, ldns_pkt_aa(pkt));
1112 ldns_pkt_set_tc(new_pkt, ldns_pkt_tc(pkt));
1113 ldns_pkt_set_rd(new_pkt, ldns_pkt_rd(pkt));
1114 ldns_pkt_set_cd(new_pkt, ldns_pkt_cd(pkt));
1115 ldns_pkt_set_ra(new_pkt, ldns_pkt_ra(pkt));
1116 ldns_pkt_set_ad(new_pkt, ldns_pkt_ad(pkt));
1117 ldns_pkt_set_opcode(new_pkt, ldns_pkt_get_opcode(pkt));
1118 ldns_pkt_set_rcode(new_pkt, ldns_pkt_get_rcode(pkt));
1119 ldns_pkt_set_qdcount(new_pkt, ldns_pkt_qdcount(pkt));
1120 ldns_pkt_set_ancount(new_pkt, ldns_pkt_ancount(pkt));
1121 ldns_pkt_set_nscount(new_pkt, ldns_pkt_nscount(pkt));
1122 ldns_pkt_set_arcount(new_pkt, ldns_pkt_arcount(pkt));
1123 if (ldns_pkt_answerfrom(pkt))
1124 ldns_pkt_set_answerfrom(new_pkt,
1125 ldns_rdf_clone(ldns_pkt_answerfrom(pkt)));
1126 ldns_pkt_set_querytime(new_pkt, ldns_pkt_querytime(pkt));
1127 ldns_pkt_set_size(new_pkt, ldns_pkt_size(pkt));
1128 ldns_pkt_set_tsig(new_pkt, ldns_rr_clone(ldns_pkt_tsig(pkt)));
1129
1130 ldns_pkt_set_edns_udp_size(new_pkt, ldns_pkt_edns_udp_size(pkt));
1131 ldns_pkt_set_edns_extended_rcode(new_pkt,
1132 ldns_pkt_edns_extended_rcode(pkt));
1133 ldns_pkt_set_edns_version(new_pkt, ldns_pkt_edns_version(pkt));
1134 ldns_pkt_set_edns_z(new_pkt, ldns_pkt_edns_z(pkt));
1135 if(ldns_pkt_edns_data(pkt))
1136 ldns_pkt_set_edns_data(new_pkt,
1137 ldns_rdf_clone(ldns_pkt_edns_data(pkt)));
1138 ldns_pkt_set_edns_do(new_pkt, ldns_pkt_edns_do(pkt));
1139
1140 ldns_rr_list_deep_free(new_pkt->_question);
1141 ldns_rr_list_deep_free(new_pkt->_answer);
1142 ldns_rr_list_deep_free(new_pkt->_authority);
1143 ldns_rr_list_deep_free(new_pkt->_additional);
1144 new_pkt->_question = ldns_rr_list_clone(ldns_pkt_question(pkt));
1145 new_pkt->_answer = ldns_rr_list_clone(ldns_pkt_answer(pkt));
1146 new_pkt->_authority = ldns_rr_list_clone(ldns_pkt_authority(pkt));
1147 new_pkt->_additional = ldns_rr_list_clone(ldns_pkt_additional(pkt));
1148 return new_pkt;
1149 }
1150