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 #define LDNS_EDNS_MASK_UNASSIGNED (0xFFFF & ~LDNS_EDNS_MASK_DO_BIT)
30
31 /* TODO defines for 3600 */
32 /* convert to and from numerical flag values */
33 ldns_lookup_table ldns_edns_flags[] = {
34 { 3600, "do"},
35 { 0, NULL}
36 };
37
38 /* read */
39 uint16_t
ldns_pkt_id(const ldns_pkt * packet)40 ldns_pkt_id(const ldns_pkt *packet)
41 {
42 return packet->_header->_id;
43 }
44
45 bool
ldns_pkt_qr(const ldns_pkt * packet)46 ldns_pkt_qr(const ldns_pkt *packet)
47 {
48 return packet->_header->_qr;
49 }
50
51 bool
ldns_pkt_aa(const ldns_pkt * packet)52 ldns_pkt_aa(const ldns_pkt *packet)
53 {
54 return packet->_header->_aa;
55 }
56
57 bool
ldns_pkt_tc(const ldns_pkt * packet)58 ldns_pkt_tc(const ldns_pkt *packet)
59 {
60 return packet->_header->_tc;
61 }
62
63 bool
ldns_pkt_rd(const ldns_pkt * packet)64 ldns_pkt_rd(const ldns_pkt *packet)
65 {
66 return packet->_header->_rd;
67 }
68
69 bool
ldns_pkt_cd(const ldns_pkt * packet)70 ldns_pkt_cd(const ldns_pkt *packet)
71 {
72 return packet->_header->_cd;
73 }
74
75 bool
ldns_pkt_ra(const ldns_pkt * packet)76 ldns_pkt_ra(const ldns_pkt *packet)
77 {
78 return packet->_header->_ra;
79 }
80
81 bool
ldns_pkt_ad(const ldns_pkt * packet)82 ldns_pkt_ad(const ldns_pkt *packet)
83 {
84 return packet->_header->_ad;
85 }
86
87 ldns_pkt_opcode
ldns_pkt_get_opcode(const ldns_pkt * packet)88 ldns_pkt_get_opcode(const ldns_pkt *packet)
89 {
90 return packet->_header->_opcode;
91 }
92
93 ldns_pkt_rcode
ldns_pkt_get_rcode(const ldns_pkt * packet)94 ldns_pkt_get_rcode(const ldns_pkt *packet)
95 {
96 return packet->_header->_rcode;
97 }
98
99 uint16_t
ldns_pkt_qdcount(const ldns_pkt * packet)100 ldns_pkt_qdcount(const ldns_pkt *packet)
101 {
102 return packet->_header->_qdcount;
103 }
104
105 uint16_t
ldns_pkt_ancount(const ldns_pkt * packet)106 ldns_pkt_ancount(const ldns_pkt *packet)
107 {
108 return packet->_header->_ancount;
109 }
110
111 uint16_t
ldns_pkt_nscount(const ldns_pkt * packet)112 ldns_pkt_nscount(const ldns_pkt *packet)
113 {
114 return packet->_header->_nscount;
115 }
116
117 uint16_t
ldns_pkt_arcount(const ldns_pkt * packet)118 ldns_pkt_arcount(const ldns_pkt *packet)
119 {
120 return packet->_header->_arcount;
121 }
122
123 ldns_rr_list *
ldns_pkt_question(const ldns_pkt * packet)124 ldns_pkt_question(const ldns_pkt *packet)
125 {
126 return packet->_question;
127 }
128
129 ldns_rr_list *
ldns_pkt_answer(const ldns_pkt * packet)130 ldns_pkt_answer(const ldns_pkt *packet)
131 {
132 return packet->_answer;
133 }
134
135 ldns_rr_list *
ldns_pkt_authority(const ldns_pkt * packet)136 ldns_pkt_authority(const ldns_pkt *packet)
137 {
138 return packet->_authority;
139 }
140
141 ldns_rr_list *
ldns_pkt_additional(const ldns_pkt * packet)142 ldns_pkt_additional(const ldns_pkt *packet)
143 {
144 return packet->_additional;
145 }
146
147 /* return ALL section concatenated */
148 ldns_rr_list *
ldns_pkt_all(const ldns_pkt * packet)149 ldns_pkt_all(const ldns_pkt *packet)
150 {
151 ldns_rr_list *all, *prev_all;
152
153 all = ldns_rr_list_cat_clone(
154 ldns_pkt_question(packet),
155 ldns_pkt_answer(packet));
156 prev_all = all;
157 all = ldns_rr_list_cat_clone(all,
158 ldns_pkt_authority(packet));
159 ldns_rr_list_deep_free(prev_all);
160 prev_all = all;
161 all = ldns_rr_list_cat_clone(all,
162 ldns_pkt_additional(packet));
163 ldns_rr_list_deep_free(prev_all);
164 return all;
165 }
166
167 ldns_rr_list *
ldns_pkt_all_noquestion(const ldns_pkt * packet)168 ldns_pkt_all_noquestion(const ldns_pkt *packet)
169 {
170 ldns_rr_list *all, *all2;
171
172 all = ldns_rr_list_cat_clone(
173 ldns_pkt_answer(packet),
174 ldns_pkt_authority(packet));
175 all2 = ldns_rr_list_cat_clone(all,
176 ldns_pkt_additional(packet));
177
178 ldns_rr_list_deep_free(all);
179 return all2;
180 }
181
182 size_t
ldns_pkt_size(const ldns_pkt * packet)183 ldns_pkt_size(const ldns_pkt *packet)
184 {
185 return packet->_size;
186 }
187
188 uint32_t
ldns_pkt_querytime(const ldns_pkt * packet)189 ldns_pkt_querytime(const ldns_pkt *packet)
190 {
191 return packet->_querytime;
192 }
193
194 ldns_rdf *
ldns_pkt_answerfrom(const ldns_pkt * packet)195 ldns_pkt_answerfrom(const ldns_pkt *packet)
196 {
197 return packet->_answerfrom;
198 }
199
200 struct timeval
ldns_pkt_timestamp(const ldns_pkt * packet)201 ldns_pkt_timestamp(const ldns_pkt *packet)
202 {
203 return packet->timestamp;
204 }
205
206 uint16_t
ldns_pkt_edns_udp_size(const ldns_pkt * packet)207 ldns_pkt_edns_udp_size(const ldns_pkt *packet)
208 {
209 return packet->_edns_udp_size;
210 }
211
212 uint8_t
ldns_pkt_edns_extended_rcode(const ldns_pkt * packet)213 ldns_pkt_edns_extended_rcode(const ldns_pkt *packet)
214 {
215 return packet->_edns_extended_rcode;
216 }
217
218 uint8_t
ldns_pkt_edns_version(const ldns_pkt * packet)219 ldns_pkt_edns_version(const ldns_pkt *packet)
220 {
221 return packet->_edns_version;
222 }
223
224 uint16_t
ldns_pkt_edns_z(const ldns_pkt * packet)225 ldns_pkt_edns_z(const ldns_pkt *packet)
226 {
227 return packet->_edns_z;
228 }
229
230 bool
ldns_pkt_edns_do(const ldns_pkt * packet)231 ldns_pkt_edns_do(const ldns_pkt *packet)
232 {
233 return (packet->_edns_z & LDNS_EDNS_MASK_DO_BIT);
234 }
235
236 void
ldns_pkt_set_edns_do(ldns_pkt * packet,bool value)237 ldns_pkt_set_edns_do(ldns_pkt *packet, bool value)
238 {
239 if (value) {
240 packet->_edns_z = packet->_edns_z | LDNS_EDNS_MASK_DO_BIT;
241 } else {
242 packet->_edns_z = packet->_edns_z & ~LDNS_EDNS_MASK_DO_BIT;
243 }
244 }
245
246 uint16_t
ldns_pkt_edns_unassigned(const ldns_pkt * packet)247 ldns_pkt_edns_unassigned(const ldns_pkt *packet)
248 {
249 return (packet->_edns_z & LDNS_EDNS_MASK_UNASSIGNED);
250 }
251
252 void
ldns_pkt_set_edns_unassigned(ldns_pkt * packet,uint16_t value)253 ldns_pkt_set_edns_unassigned(ldns_pkt *packet, uint16_t value)
254 {
255 packet->_edns_z = (packet->_edns_z & ~LDNS_EDNS_MASK_UNASSIGNED)
256 | (value & LDNS_EDNS_MASK_UNASSIGNED);
257 }
258
259 ldns_rdf *
ldns_pkt_edns_data(const ldns_pkt * packet)260 ldns_pkt_edns_data(const ldns_pkt *packet)
261 {
262 return packet->_edns_data;
263 }
264
265 /* return only those rr that share the ownername */
266 ldns_rr_list *
ldns_pkt_rr_list_by_name(const ldns_pkt * packet,const ldns_rdf * ownername,ldns_pkt_section sec)267 ldns_pkt_rr_list_by_name(const ldns_pkt *packet,
268 const ldns_rdf *ownername,
269 ldns_pkt_section sec)
270 {
271 ldns_rr_list *rrs;
272 ldns_rr_list *ret;
273 uint16_t i;
274
275 if (!packet) {
276 return NULL;
277 }
278
279 rrs = ldns_pkt_get_section_clone(packet, sec);
280 ret = NULL;
281
282 for(i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
283 if (ldns_dname_compare(ldns_rr_owner(
284 ldns_rr_list_rr(rrs, i)),
285 ownername) == 0) {
286 /* owner names match */
287 if (ret == NULL) {
288 ret = ldns_rr_list_new();
289 }
290 ldns_rr_list_push_rr(ret,
291 ldns_rr_clone(
292 ldns_rr_list_rr(rrs, i))
293 );
294 }
295 }
296
297 ldns_rr_list_deep_free(rrs);
298
299 return ret;
300 }
301
302 /* return only those rr that share a type */
303 ldns_rr_list *
ldns_pkt_rr_list_by_type(const ldns_pkt * packet,ldns_rr_type type,ldns_pkt_section sec)304 ldns_pkt_rr_list_by_type(const ldns_pkt *packet,
305 ldns_rr_type type,
306 ldns_pkt_section sec)
307 {
308 ldns_rr_list *rrs;
309 ldns_rr_list *new;
310 uint16_t i;
311
312 if(!packet) {
313 return NULL;
314 }
315
316 rrs = ldns_pkt_get_section_clone(packet, sec);
317 new = ldns_rr_list_new();
318
319 for(i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
320 if (type == ldns_rr_get_type(ldns_rr_list_rr(rrs, i))) {
321 /* types match */
322 ldns_rr_list_push_rr(new,
323 ldns_rr_clone(
324 ldns_rr_list_rr(rrs, i))
325 );
326 }
327 }
328 ldns_rr_list_deep_free(rrs);
329
330 if (ldns_rr_list_rr_count(new) == 0) {
331 ldns_rr_list_free(new);
332 return NULL;
333 } else {
334 return new;
335 }
336 }
337
338 /* return only those rrs that share name and type */
339 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)340 ldns_pkt_rr_list_by_name_and_type(const ldns_pkt *packet,
341 const ldns_rdf *ownername,
342 ldns_rr_type type,
343 ldns_pkt_section sec)
344 {
345 ldns_rr_list *rrs;
346 ldns_rr_list *new;
347 ldns_rr_list *ret;
348 uint16_t i;
349
350 if(!packet) {
351 return NULL;
352 }
353
354 rrs = ldns_pkt_get_section_clone(packet, sec);
355 new = ldns_rr_list_new();
356 ret = NULL;
357
358 for(i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
359 if (type == ldns_rr_get_type(ldns_rr_list_rr(rrs, i)) &&
360 ldns_dname_compare(ldns_rr_owner(ldns_rr_list_rr(rrs, i)),
361 ownername
362 ) == 0
363 ) {
364 /* types match */
365 ldns_rr_list_push_rr(new, ldns_rr_clone(ldns_rr_list_rr(rrs, i)));
366 ret = new;
367 }
368 }
369 ldns_rr_list_deep_free(rrs);
370 if (!ret) {
371 ldns_rr_list_free(new);
372 }
373 return ret;
374 }
375
376 bool
ldns_pkt_rr(const ldns_pkt * pkt,ldns_pkt_section sec,const ldns_rr * rr)377 ldns_pkt_rr(const ldns_pkt *pkt, ldns_pkt_section sec, const ldns_rr *rr)
378 {
379 bool result = false;
380
381 switch (sec) {
382 case LDNS_SECTION_QUESTION:
383 return ldns_rr_list_contains_rr(ldns_pkt_question(pkt), rr);
384 case LDNS_SECTION_ANSWER:
385 return ldns_rr_list_contains_rr(ldns_pkt_answer(pkt), rr);
386 case LDNS_SECTION_AUTHORITY:
387 return ldns_rr_list_contains_rr(ldns_pkt_authority(pkt), rr);
388 case LDNS_SECTION_ADDITIONAL:
389 return ldns_rr_list_contains_rr(ldns_pkt_additional(pkt), rr);
390 case LDNS_SECTION_ANY:
391 result = ldns_rr_list_contains_rr(ldns_pkt_question(pkt), rr);
392 /* fallthrough */
393 case LDNS_SECTION_ANY_NOQUESTION:
394 result = result
395 || ldns_rr_list_contains_rr(ldns_pkt_answer(pkt), rr)
396 || ldns_rr_list_contains_rr(ldns_pkt_authority(pkt), rr)
397 || ldns_rr_list_contains_rr(ldns_pkt_additional(pkt), rr);
398 }
399
400 return result;
401 }
402
403 uint16_t
ldns_pkt_section_count(const ldns_pkt * packet,ldns_pkt_section s)404 ldns_pkt_section_count(const ldns_pkt *packet, ldns_pkt_section s)
405 {
406 switch(s) {
407 case LDNS_SECTION_QUESTION:
408 return ldns_pkt_qdcount(packet);
409 case LDNS_SECTION_ANSWER:
410 return ldns_pkt_ancount(packet);
411 case LDNS_SECTION_AUTHORITY:
412 return ldns_pkt_nscount(packet);
413 case LDNS_SECTION_ADDITIONAL:
414 return ldns_pkt_arcount(packet);
415 case LDNS_SECTION_ANY:
416 return ldns_pkt_qdcount(packet) +
417 ldns_pkt_ancount(packet) +
418 ldns_pkt_nscount(packet) +
419 ldns_pkt_arcount(packet);
420 case LDNS_SECTION_ANY_NOQUESTION:
421 return ldns_pkt_ancount(packet) +
422 ldns_pkt_nscount(packet) +
423 ldns_pkt_arcount(packet);
424 default:
425 return 0;
426 }
427 }
428
429 bool
ldns_pkt_empty(ldns_pkt * p)430 ldns_pkt_empty(ldns_pkt *p)
431 {
432 if (!p) {
433 return true; /* NULL is empty? */
434 }
435 if (ldns_pkt_section_count(p, LDNS_SECTION_ANY) > 0) {
436 return false;
437 } else {
438 return true;
439 }
440 }
441
442
443 ldns_rr_list *
ldns_pkt_get_section_clone(const ldns_pkt * packet,ldns_pkt_section s)444 ldns_pkt_get_section_clone(const ldns_pkt *packet, ldns_pkt_section s)
445 {
446 switch(s) {
447 case LDNS_SECTION_QUESTION:
448 return ldns_rr_list_clone(ldns_pkt_question(packet));
449 case LDNS_SECTION_ANSWER:
450 return ldns_rr_list_clone(ldns_pkt_answer(packet));
451 case LDNS_SECTION_AUTHORITY:
452 return ldns_rr_list_clone(ldns_pkt_authority(packet));
453 case LDNS_SECTION_ADDITIONAL:
454 return ldns_rr_list_clone(ldns_pkt_additional(packet));
455 case LDNS_SECTION_ANY:
456 /* these are already clones */
457 return ldns_pkt_all(packet);
458 case LDNS_SECTION_ANY_NOQUESTION:
459 return ldns_pkt_all_noquestion(packet);
460 default:
461 return NULL;
462 }
463 }
464
ldns_pkt_tsig(const ldns_pkt * pkt)465 ldns_rr *ldns_pkt_tsig(const ldns_pkt *pkt) {
466 return pkt->_tsig_rr;
467 }
468
469 /* write */
470 void
ldns_pkt_set_id(ldns_pkt * packet,uint16_t id)471 ldns_pkt_set_id(ldns_pkt *packet, uint16_t id)
472 {
473 packet->_header->_id = id;
474 }
475
476 void
ldns_pkt_set_random_id(ldns_pkt * packet)477 ldns_pkt_set_random_id(ldns_pkt *packet)
478 {
479 uint16_t rid = ldns_get_random();
480 ldns_pkt_set_id(packet, rid);
481 }
482
483
484 void
ldns_pkt_set_qr(ldns_pkt * packet,bool qr)485 ldns_pkt_set_qr(ldns_pkt *packet, bool qr)
486 {
487 packet->_header->_qr = qr;
488 }
489
490 void
ldns_pkt_set_aa(ldns_pkt * packet,bool aa)491 ldns_pkt_set_aa(ldns_pkt *packet, bool aa)
492 {
493 packet->_header->_aa = aa;
494 }
495
496 void
ldns_pkt_set_tc(ldns_pkt * packet,bool tc)497 ldns_pkt_set_tc(ldns_pkt *packet, bool tc)
498 {
499 packet->_header->_tc = tc;
500 }
501
502 void
ldns_pkt_set_rd(ldns_pkt * packet,bool rd)503 ldns_pkt_set_rd(ldns_pkt *packet, bool rd)
504 {
505 packet->_header->_rd = rd;
506 }
507
508 void
ldns_pkt_set_additional(ldns_pkt * p,ldns_rr_list * rr)509 ldns_pkt_set_additional(ldns_pkt *p, ldns_rr_list *rr)
510 {
511 p->_additional = rr;
512 }
513
514 void
ldns_pkt_set_question(ldns_pkt * p,ldns_rr_list * rr)515 ldns_pkt_set_question(ldns_pkt *p, ldns_rr_list *rr)
516 {
517 p->_question = rr;
518 }
519
520 void
ldns_pkt_set_answer(ldns_pkt * p,ldns_rr_list * rr)521 ldns_pkt_set_answer(ldns_pkt *p, ldns_rr_list *rr)
522 {
523 p->_answer = rr;
524 }
525
526 void
ldns_pkt_set_authority(ldns_pkt * p,ldns_rr_list * rr)527 ldns_pkt_set_authority(ldns_pkt *p, ldns_rr_list *rr)
528 {
529 p->_authority = rr;
530 }
531
532 void
ldns_pkt_set_cd(ldns_pkt * packet,bool cd)533 ldns_pkt_set_cd(ldns_pkt *packet, bool cd)
534 {
535 packet->_header->_cd = cd;
536 }
537
538 void
ldns_pkt_set_ra(ldns_pkt * packet,bool ra)539 ldns_pkt_set_ra(ldns_pkt *packet, bool ra)
540 {
541 packet->_header->_ra = ra;
542 }
543
544 void
ldns_pkt_set_ad(ldns_pkt * packet,bool ad)545 ldns_pkt_set_ad(ldns_pkt *packet, bool ad)
546 {
547 packet->_header->_ad = ad;
548 }
549
550 void
ldns_pkt_set_opcode(ldns_pkt * packet,ldns_pkt_opcode opcode)551 ldns_pkt_set_opcode(ldns_pkt *packet, ldns_pkt_opcode opcode)
552 {
553 packet->_header->_opcode = opcode;
554 }
555
556 void
ldns_pkt_set_rcode(ldns_pkt * packet,uint8_t rcode)557 ldns_pkt_set_rcode(ldns_pkt *packet, uint8_t rcode)
558 {
559 packet->_header->_rcode = rcode;
560 }
561
562 void
ldns_pkt_set_qdcount(ldns_pkt * packet,uint16_t qdcount)563 ldns_pkt_set_qdcount(ldns_pkt *packet, uint16_t qdcount)
564 {
565 packet->_header->_qdcount = qdcount;
566 }
567
568 void
ldns_pkt_set_ancount(ldns_pkt * packet,uint16_t ancount)569 ldns_pkt_set_ancount(ldns_pkt *packet, uint16_t ancount)
570 {
571 packet->_header->_ancount = ancount;
572 }
573
574 void
ldns_pkt_set_nscount(ldns_pkt * packet,uint16_t nscount)575 ldns_pkt_set_nscount(ldns_pkt *packet, uint16_t nscount)
576 {
577 packet->_header->_nscount = nscount;
578 }
579
580 void
ldns_pkt_set_arcount(ldns_pkt * packet,uint16_t arcount)581 ldns_pkt_set_arcount(ldns_pkt *packet, uint16_t arcount)
582 {
583 packet->_header->_arcount = arcount;
584 }
585
586 void
ldns_pkt_set_querytime(ldns_pkt * packet,uint32_t time)587 ldns_pkt_set_querytime(ldns_pkt *packet, uint32_t time)
588 {
589 packet->_querytime = time;
590 }
591
592 void
ldns_pkt_set_answerfrom(ldns_pkt * packet,ldns_rdf * answerfrom)593 ldns_pkt_set_answerfrom(ldns_pkt *packet, ldns_rdf *answerfrom)
594 {
595 packet->_answerfrom = answerfrom;
596 }
597
598 void
ldns_pkt_set_timestamp(ldns_pkt * packet,struct timeval timeval)599 ldns_pkt_set_timestamp(ldns_pkt *packet, struct timeval timeval)
600 {
601 packet->timestamp.tv_sec = timeval.tv_sec;
602 packet->timestamp.tv_usec = timeval.tv_usec;
603 }
604
605 void
ldns_pkt_set_size(ldns_pkt * packet,size_t s)606 ldns_pkt_set_size(ldns_pkt *packet, size_t s)
607 {
608 packet->_size = s;
609 }
610
611 void
ldns_pkt_set_edns_udp_size(ldns_pkt * packet,uint16_t s)612 ldns_pkt_set_edns_udp_size(ldns_pkt *packet, uint16_t s)
613 {
614 packet->_edns_udp_size = s;
615 }
616
617 void
ldns_pkt_set_edns_extended_rcode(ldns_pkt * packet,uint8_t c)618 ldns_pkt_set_edns_extended_rcode(ldns_pkt *packet, uint8_t c)
619 {
620 packet->_edns_extended_rcode = c;
621 }
622
623 void
ldns_pkt_set_edns_version(ldns_pkt * packet,uint8_t v)624 ldns_pkt_set_edns_version(ldns_pkt *packet, uint8_t v)
625 {
626 packet->_edns_version = v;
627 }
628
629 void
ldns_pkt_set_edns_z(ldns_pkt * packet,uint16_t z)630 ldns_pkt_set_edns_z(ldns_pkt *packet, uint16_t z)
631 {
632 packet->_edns_z = z;
633 }
634
635 void
ldns_pkt_set_edns_data(ldns_pkt * packet,ldns_rdf * data)636 ldns_pkt_set_edns_data(ldns_pkt *packet, ldns_rdf *data)
637 {
638 packet->_edns_data = data;
639 }
640
641 void
ldns_pkt_set_section_count(ldns_pkt * packet,ldns_pkt_section s,uint16_t count)642 ldns_pkt_set_section_count(ldns_pkt *packet, ldns_pkt_section s, uint16_t count)
643 {
644 switch(s) {
645 case LDNS_SECTION_QUESTION:
646 ldns_pkt_set_qdcount(packet, count);
647 break;
648 case LDNS_SECTION_ANSWER:
649 ldns_pkt_set_ancount(packet, count);
650 break;
651 case LDNS_SECTION_AUTHORITY:
652 ldns_pkt_set_nscount(packet, count);
653 break;
654 case LDNS_SECTION_ADDITIONAL:
655 ldns_pkt_set_arcount(packet, count);
656 break;
657 case LDNS_SECTION_ANY:
658 case LDNS_SECTION_ANY_NOQUESTION:
659 break;
660 }
661 }
662
ldns_pkt_set_tsig(ldns_pkt * pkt,ldns_rr * rr)663 void ldns_pkt_set_tsig(ldns_pkt *pkt, ldns_rr *rr)
664 {
665 pkt->_tsig_rr = rr;
666 }
667
668 bool
ldns_pkt_push_rr(ldns_pkt * packet,ldns_pkt_section section,ldns_rr * rr)669 ldns_pkt_push_rr(ldns_pkt *packet, ldns_pkt_section section, ldns_rr *rr)
670 {
671 switch(section) {
672 case LDNS_SECTION_QUESTION:
673 if (!ldns_rr_list_push_rr(ldns_pkt_question(packet), rr)) {
674 return false;
675 }
676 ldns_pkt_set_qdcount(packet, ldns_pkt_qdcount(packet) + 1);
677 break;
678 case LDNS_SECTION_ANSWER:
679 if (!ldns_rr_list_push_rr(ldns_pkt_answer(packet), rr)) {
680 return false;
681 }
682 ldns_pkt_set_ancount(packet, ldns_pkt_ancount(packet) + 1);
683 break;
684 case LDNS_SECTION_AUTHORITY:
685 if (!ldns_rr_list_push_rr(ldns_pkt_authority(packet), rr)) {
686 return false;
687 }
688 ldns_pkt_set_nscount(packet, ldns_pkt_nscount(packet) + 1);
689 break;
690 case LDNS_SECTION_ADDITIONAL:
691 if (!ldns_rr_list_push_rr(ldns_pkt_additional(packet), rr)) {
692 return false;
693 }
694 ldns_pkt_set_arcount(packet, ldns_pkt_arcount(packet) + 1);
695 break;
696 case LDNS_SECTION_ANY:
697 case LDNS_SECTION_ANY_NOQUESTION:
698 /* shouldn't this error? */
699 break;
700 }
701 return true;
702 }
703
704 bool
ldns_pkt_safe_push_rr(ldns_pkt * pkt,ldns_pkt_section sec,ldns_rr * rr)705 ldns_pkt_safe_push_rr(ldns_pkt *pkt, ldns_pkt_section sec, ldns_rr *rr)
706 {
707
708 /* check to see if its there */
709 if (ldns_pkt_rr(pkt, sec, rr)) {
710 /* already there */
711 return false;
712 }
713 return ldns_pkt_push_rr(pkt, sec, rr);
714 }
715
716 bool
ldns_pkt_push_rr_list(ldns_pkt * p,ldns_pkt_section s,ldns_rr_list * list)717 ldns_pkt_push_rr_list(ldns_pkt *p, ldns_pkt_section s, ldns_rr_list *list)
718 {
719 size_t i;
720 for(i = 0; i < ldns_rr_list_rr_count(list); i++) {
721 if (!ldns_pkt_push_rr(p, s, ldns_rr_list_rr(list, i))) {
722 return false;
723 }
724 }
725 return true;
726 }
727
728 bool
ldns_pkt_safe_push_rr_list(ldns_pkt * p,ldns_pkt_section s,ldns_rr_list * list)729 ldns_pkt_safe_push_rr_list(ldns_pkt *p, ldns_pkt_section s, ldns_rr_list *list)
730 {
731 size_t i;
732 for(i = 0; i < ldns_rr_list_rr_count(list); i++) {
733 if (!ldns_pkt_safe_push_rr(p, s, ldns_rr_list_rr(list, i))) {
734 return false;
735 }
736 }
737 return true;
738 }
739
740 bool
ldns_pkt_edns(const ldns_pkt * pkt)741 ldns_pkt_edns(const ldns_pkt *pkt) {
742 return (ldns_pkt_edns_udp_size(pkt) > 0 ||
743 ldns_pkt_edns_extended_rcode(pkt) > 0 ||
744 ldns_pkt_edns_data(pkt) ||
745 ldns_pkt_edns_do(pkt) ||
746 pkt->_edns_present
747 );
748 }
749
750
751 /* Create/destroy/convert functions
752 */
753 ldns_pkt *
ldns_pkt_new(void)754 ldns_pkt_new(void)
755 {
756 ldns_pkt *packet;
757 packet = LDNS_MALLOC(ldns_pkt);
758 if (!packet) {
759 return NULL;
760 }
761
762 packet->_header = LDNS_MALLOC(ldns_hdr);
763 if (!packet->_header) {
764 LDNS_FREE(packet);
765 return NULL;
766 }
767
768 packet->_question = ldns_rr_list_new();
769 packet->_answer = ldns_rr_list_new();
770 packet->_authority = ldns_rr_list_new();
771 packet->_additional = ldns_rr_list_new();
772
773 /* default everything to false */
774 ldns_pkt_set_qr(packet, false);
775 ldns_pkt_set_aa(packet, false);
776 ldns_pkt_set_tc(packet, false);
777 ldns_pkt_set_rd(packet, false);
778 ldns_pkt_set_ra(packet, false);
779 ldns_pkt_set_ad(packet, false);
780 ldns_pkt_set_cd(packet, false);
781
782 ldns_pkt_set_opcode(packet, LDNS_PACKET_QUERY);
783 ldns_pkt_set_rcode(packet, 0);
784 ldns_pkt_set_id(packet, 0);
785 ldns_pkt_set_size(packet, 0);
786 ldns_pkt_set_querytime(packet, 0);
787 memset(&packet->timestamp, 0, sizeof(packet->timestamp));
788 ldns_pkt_set_answerfrom(packet, NULL);
789 ldns_pkt_set_section_count(packet, LDNS_SECTION_QUESTION, 0);
790 ldns_pkt_set_section_count(packet, LDNS_SECTION_ANSWER, 0);
791 ldns_pkt_set_section_count(packet, LDNS_SECTION_AUTHORITY, 0);
792 ldns_pkt_set_section_count(packet, LDNS_SECTION_ADDITIONAL, 0);
793
794 ldns_pkt_set_edns_udp_size(packet, 0);
795 ldns_pkt_set_edns_extended_rcode(packet, 0);
796 ldns_pkt_set_edns_version(packet, 0);
797 ldns_pkt_set_edns_z(packet, 0);
798 ldns_pkt_set_edns_data(packet, NULL);
799 packet->_edns_present = false;
800
801 ldns_pkt_set_tsig(packet, NULL);
802
803 return packet;
804 }
805
806 void
ldns_pkt_free(ldns_pkt * packet)807 ldns_pkt_free(ldns_pkt *packet)
808 {
809 if (packet) {
810 LDNS_FREE(packet->_header);
811 ldns_rr_list_deep_free(packet->_question);
812 ldns_rr_list_deep_free(packet->_answer);
813 ldns_rr_list_deep_free(packet->_authority);
814 ldns_rr_list_deep_free(packet->_additional);
815 ldns_rr_free(packet->_tsig_rr);
816 ldns_rdf_deep_free(packet->_edns_data);
817 ldns_rdf_deep_free(packet->_answerfrom);
818 LDNS_FREE(packet);
819 }
820 }
821
822 bool
ldns_pkt_set_flags(ldns_pkt * packet,uint16_t flags)823 ldns_pkt_set_flags(ldns_pkt *packet, uint16_t flags)
824 {
825 if (!packet) {
826 return false;
827 }
828 if ((flags & LDNS_QR) == LDNS_QR) {
829 ldns_pkt_set_qr(packet, true);
830 }
831 if ((flags & LDNS_AA) == LDNS_AA) {
832 ldns_pkt_set_aa(packet, true);
833 }
834 if ((flags & LDNS_RD) == LDNS_RD) {
835 ldns_pkt_set_rd(packet, true);
836 }
837 if ((flags & LDNS_TC) == LDNS_TC) {
838 ldns_pkt_set_tc(packet, true);
839 }
840 if ((flags & LDNS_CD) == LDNS_CD) {
841 ldns_pkt_set_cd(packet, true);
842 }
843 if ((flags & LDNS_RA) == LDNS_RA) {
844 ldns_pkt_set_ra(packet, true);
845 }
846 if ((flags & LDNS_AD) == LDNS_AD) {
847 ldns_pkt_set_ad(packet, true);
848 }
849 return true;
850 }
851
852
853 static ldns_rr*
ldns_pkt_authsoa(const ldns_rdf * rr_name,ldns_rr_class rr_class)854 ldns_pkt_authsoa(const ldns_rdf* rr_name, ldns_rr_class rr_class)
855 {
856 ldns_rr* soa_rr = ldns_rr_new();
857 ldns_rdf *owner_rdf;
858 ldns_rdf *mname_rdf;
859 ldns_rdf *rname_rdf;
860 ldns_rdf *serial_rdf;
861 ldns_rdf *refresh_rdf;
862 ldns_rdf *retry_rdf;
863 ldns_rdf *expire_rdf;
864 ldns_rdf *minimum_rdf;
865
866 if (!soa_rr) {
867 return NULL;
868 }
869 owner_rdf = ldns_rdf_clone(rr_name);
870 if (!owner_rdf) {
871 ldns_rr_free(soa_rr);
872 return NULL;
873 }
874
875 ldns_rr_set_owner(soa_rr, owner_rdf);
876 ldns_rr_set_type(soa_rr, LDNS_RR_TYPE_SOA);
877 ldns_rr_set_class(soa_rr, rr_class);
878 ldns_rr_set_question(soa_rr, false);
879
880 if (ldns_str2rdf_dname(&mname_rdf, ".") != LDNS_STATUS_OK) {
881 ldns_rr_free(soa_rr);
882 return NULL;
883 } else {
884 ldns_rr_push_rdf(soa_rr, mname_rdf);
885 }
886 if (ldns_str2rdf_dname(&rname_rdf, ".") != LDNS_STATUS_OK) {
887 ldns_rr_free(soa_rr);
888 return NULL;
889 } else {
890 ldns_rr_push_rdf(soa_rr, rname_rdf);
891 }
892 serial_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
893 if (!serial_rdf) {
894 ldns_rr_free(soa_rr);
895 return NULL;
896 } else {
897 ldns_rr_push_rdf(soa_rr, serial_rdf);
898 }
899 refresh_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
900 if (!refresh_rdf) {
901 ldns_rr_free(soa_rr);
902 return NULL;
903 } else {
904 ldns_rr_push_rdf(soa_rr, refresh_rdf);
905 }
906 retry_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
907 if (!retry_rdf) {
908 ldns_rr_free(soa_rr);
909 return NULL;
910 } else {
911 ldns_rr_push_rdf(soa_rr, retry_rdf);
912 }
913 expire_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
914 if (!expire_rdf) {
915 ldns_rr_free(soa_rr);
916 return NULL;
917 } else {
918 ldns_rr_push_rdf(soa_rr, expire_rdf);
919 }
920 minimum_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
921 if (!minimum_rdf) {
922 ldns_rr_free(soa_rr);
923 return NULL;
924 } else {
925 ldns_rr_push_rdf(soa_rr, minimum_rdf);
926 }
927 return soa_rr;
928 }
929
930
931 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)932 ldns_pkt_query_new_frm_str_internal(ldns_pkt **p, const char *name,
933 ldns_rr_type rr_type, ldns_rr_class rr_class, uint16_t flags,
934 ldns_rr* authsoa_rr)
935 {
936 ldns_pkt *packet;
937 ldns_rr *question_rr;
938 ldns_rdf *name_rdf;
939
940 packet = ldns_pkt_new();
941 if (!packet) {
942 return LDNS_STATUS_MEM_ERR;
943 }
944
945 if (!ldns_pkt_set_flags(packet, flags)) {
946 ldns_pkt_free(packet);
947 return LDNS_STATUS_ERR;
948 }
949
950 question_rr = ldns_rr_new();
951 if (!question_rr) {
952 ldns_pkt_free(packet);
953 return LDNS_STATUS_MEM_ERR;
954 }
955
956 if (rr_type == 0) {
957 rr_type = LDNS_RR_TYPE_A;
958 }
959 if (rr_class == 0) {
960 rr_class = LDNS_RR_CLASS_IN;
961 }
962
963 if (ldns_str2rdf_dname(&name_rdf, name) == LDNS_STATUS_OK) {
964 ldns_rr_set_owner(question_rr, name_rdf);
965 ldns_rr_set_type(question_rr, rr_type);
966 ldns_rr_set_class(question_rr, rr_class);
967 ldns_rr_set_question(question_rr, true);
968
969 ldns_pkt_push_rr(packet, LDNS_SECTION_QUESTION, question_rr);
970 } else {
971 ldns_rr_free(question_rr);
972 ldns_pkt_free(packet);
973 return LDNS_STATUS_ERR;
974 }
975
976 if (authsoa_rr) {
977 ldns_pkt_push_rr(packet, LDNS_SECTION_AUTHORITY, authsoa_rr);
978 }
979
980 packet->_tsig_rr = NULL;
981 ldns_pkt_set_answerfrom(packet, NULL);
982 if (p) {
983 *p = packet;
984 return LDNS_STATUS_OK;
985 } else {
986 ldns_pkt_free(packet);
987 return LDNS_STATUS_NULL;
988 }
989 }
990
991 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)992 ldns_pkt_query_new_frm_str(ldns_pkt **p, const char *name,
993 ldns_rr_type rr_type, ldns_rr_class rr_class, uint16_t flags)
994 {
995 return ldns_pkt_query_new_frm_str_internal(p, name, rr_type,
996 rr_class, flags, NULL);
997 }
998
999 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)1000 ldns_pkt_ixfr_request_new_frm_str(ldns_pkt **p, const char *name,
1001 ldns_rr_class rr_class, uint16_t flags, ldns_rr *soa)
1002 {
1003 ldns_rr* authsoa_rr = soa;
1004 if (!authsoa_rr) {
1005 ldns_rdf *name_rdf;
1006 if (ldns_str2rdf_dname(&name_rdf, name) == LDNS_STATUS_OK) {
1007 authsoa_rr = ldns_pkt_authsoa(name_rdf, rr_class);
1008 }
1009 ldns_rdf_free(name_rdf);
1010 }
1011 return ldns_pkt_query_new_frm_str_internal(p, name, LDNS_RR_TYPE_IXFR,
1012 rr_class, flags, authsoa_rr);
1013 }
1014
1015 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)1016 ldns_pkt_query_new_internal(ldns_rdf *rr_name, ldns_rr_type rr_type,
1017 ldns_rr_class rr_class, uint16_t flags, ldns_rr* authsoa_rr)
1018 {
1019 ldns_pkt *packet;
1020 ldns_rr *question_rr;
1021
1022 packet = ldns_pkt_new();
1023 if (!packet) {
1024 return NULL;
1025 }
1026
1027 if (!ldns_pkt_set_flags(packet, flags)) {
1028 return NULL;
1029 }
1030
1031 question_rr = ldns_rr_new();
1032 if (!question_rr) {
1033 ldns_pkt_free(packet);
1034 return NULL;
1035 }
1036
1037 if (rr_type == 0) {
1038 rr_type = LDNS_RR_TYPE_A;
1039 }
1040 if (rr_class == 0) {
1041 rr_class = LDNS_RR_CLASS_IN;
1042 }
1043
1044 ldns_rr_set_owner(question_rr, rr_name);
1045 ldns_rr_set_type(question_rr, rr_type);
1046 ldns_rr_set_class(question_rr, rr_class);
1047 ldns_rr_set_question(question_rr, true);
1048 ldns_pkt_push_rr(packet, LDNS_SECTION_QUESTION, question_rr);
1049
1050 if (authsoa_rr) {
1051 ldns_pkt_push_rr(packet, LDNS_SECTION_AUTHORITY, authsoa_rr);
1052 }
1053
1054 packet->_tsig_rr = NULL;
1055 return packet;
1056 }
1057
1058 ldns_pkt *
ldns_pkt_query_new(ldns_rdf * rr_name,ldns_rr_type rr_type,ldns_rr_class rr_class,uint16_t flags)1059 ldns_pkt_query_new(ldns_rdf *rr_name, ldns_rr_type rr_type,
1060 ldns_rr_class rr_class, uint16_t flags)
1061 {
1062 return ldns_pkt_query_new_internal(rr_name, rr_type,
1063 rr_class, flags, NULL);
1064 }
1065
1066 ldns_pkt *
ldns_pkt_ixfr_request_new(ldns_rdf * rr_name,ldns_rr_class rr_class,uint16_t flags,ldns_rr * soa)1067 ldns_pkt_ixfr_request_new(ldns_rdf *rr_name, ldns_rr_class rr_class,
1068 uint16_t flags, ldns_rr* soa)
1069 {
1070 ldns_rr* authsoa_rr = soa;
1071 if (!authsoa_rr) {
1072 authsoa_rr = ldns_pkt_authsoa(rr_name, rr_class);
1073 }
1074 return ldns_pkt_query_new_internal(rr_name, LDNS_RR_TYPE_IXFR,
1075 rr_class, flags, authsoa_rr);
1076 }
1077
1078 ldns_pkt_type
ldns_pkt_reply_type(const ldns_pkt * p)1079 ldns_pkt_reply_type(const ldns_pkt *p)
1080 {
1081 ldns_rr_list *tmp;
1082
1083 if (!p) {
1084 return LDNS_PACKET_UNKNOWN;
1085 }
1086
1087 if (ldns_pkt_get_rcode(p) == LDNS_RCODE_NXDOMAIN) {
1088 return LDNS_PACKET_NXDOMAIN;
1089 }
1090
1091 if (ldns_pkt_ancount(p) == 0 && ldns_pkt_arcount(p) == 0
1092 && ldns_pkt_nscount(p) == 1) {
1093
1094 /* check for SOA */
1095 tmp = ldns_pkt_rr_list_by_type(p, LDNS_RR_TYPE_SOA,
1096 LDNS_SECTION_AUTHORITY);
1097 if (tmp) {
1098 ldns_rr_list_deep_free(tmp);
1099 return LDNS_PACKET_NODATA;
1100 } else {
1101 /* I have no idea ... */
1102 }
1103 }
1104
1105 if (ldns_pkt_ancount(p) == 0 && ldns_pkt_nscount(p) > 0) {
1106 tmp = ldns_pkt_rr_list_by_type(p, LDNS_RR_TYPE_NS,
1107 LDNS_SECTION_AUTHORITY);
1108 if (tmp) {
1109 /* there are nameservers here */
1110 ldns_rr_list_deep_free(tmp);
1111 return LDNS_PACKET_REFERRAL;
1112 } else {
1113 /* I have no idea */
1114 }
1115 ldns_rr_list_deep_free(tmp);
1116 }
1117
1118 /* if we cannot determine the packet type, we say it's an
1119 * answer...
1120 */
1121 return LDNS_PACKET_ANSWER;
1122 }
1123
1124 ldns_pkt *
ldns_pkt_clone(const ldns_pkt * pkt)1125 ldns_pkt_clone(const ldns_pkt *pkt)
1126 {
1127 ldns_pkt *new_pkt;
1128
1129 if (!pkt) {
1130 return NULL;
1131 }
1132 new_pkt = ldns_pkt_new();
1133
1134 ldns_pkt_set_id(new_pkt, ldns_pkt_id(pkt));
1135 ldns_pkt_set_qr(new_pkt, ldns_pkt_qr(pkt));
1136 ldns_pkt_set_aa(new_pkt, ldns_pkt_aa(pkt));
1137 ldns_pkt_set_tc(new_pkt, ldns_pkt_tc(pkt));
1138 ldns_pkt_set_rd(new_pkt, ldns_pkt_rd(pkt));
1139 ldns_pkt_set_cd(new_pkt, ldns_pkt_cd(pkt));
1140 ldns_pkt_set_ra(new_pkt, ldns_pkt_ra(pkt));
1141 ldns_pkt_set_ad(new_pkt, ldns_pkt_ad(pkt));
1142 ldns_pkt_set_opcode(new_pkt, ldns_pkt_get_opcode(pkt));
1143 ldns_pkt_set_rcode(new_pkt, ldns_pkt_get_rcode(pkt));
1144 ldns_pkt_set_qdcount(new_pkt, ldns_pkt_qdcount(pkt));
1145 ldns_pkt_set_ancount(new_pkt, ldns_pkt_ancount(pkt));
1146 ldns_pkt_set_nscount(new_pkt, ldns_pkt_nscount(pkt));
1147 ldns_pkt_set_arcount(new_pkt, ldns_pkt_arcount(pkt));
1148 if (ldns_pkt_answerfrom(pkt))
1149 ldns_pkt_set_answerfrom(new_pkt,
1150 ldns_rdf_clone(ldns_pkt_answerfrom(pkt)));
1151 ldns_pkt_set_timestamp(new_pkt, ldns_pkt_timestamp(pkt));
1152 ldns_pkt_set_querytime(new_pkt, ldns_pkt_querytime(pkt));
1153 ldns_pkt_set_size(new_pkt, ldns_pkt_size(pkt));
1154 ldns_pkt_set_tsig(new_pkt, ldns_rr_clone(ldns_pkt_tsig(pkt)));
1155
1156 ldns_pkt_set_edns_udp_size(new_pkt, ldns_pkt_edns_udp_size(pkt));
1157 ldns_pkt_set_edns_extended_rcode(new_pkt,
1158 ldns_pkt_edns_extended_rcode(pkt));
1159 ldns_pkt_set_edns_version(new_pkt, ldns_pkt_edns_version(pkt));
1160 new_pkt->_edns_present = pkt->_edns_present;
1161 ldns_pkt_set_edns_z(new_pkt, ldns_pkt_edns_z(pkt));
1162 if(ldns_pkt_edns_data(pkt))
1163 ldns_pkt_set_edns_data(new_pkt,
1164 ldns_rdf_clone(ldns_pkt_edns_data(pkt)));
1165 ldns_pkt_set_edns_do(new_pkt, ldns_pkt_edns_do(pkt));
1166
1167 ldns_rr_list_deep_free(new_pkt->_question);
1168 ldns_rr_list_deep_free(new_pkt->_answer);
1169 ldns_rr_list_deep_free(new_pkt->_authority);
1170 ldns_rr_list_deep_free(new_pkt->_additional);
1171 new_pkt->_question = ldns_rr_list_clone(ldns_pkt_question(pkt));
1172 new_pkt->_answer = ldns_rr_list_clone(ldns_pkt_answer(pkt));
1173 new_pkt->_authority = ldns_rr_list_clone(ldns_pkt_authority(pkt));
1174 new_pkt->_additional = ldns_rr_list_clone(ldns_pkt_additional(pkt));
1175 return new_pkt;
1176 }
1177