1 /*
2 * Copyright (c) 1995 - 2006 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the Institute nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34
35 #include <config.h>
36
37 #include "roken.h"
38 #ifdef HAVE_ARPA_NAMESER_H
39 #include <arpa/nameser.h>
40 #endif
41 #ifdef HAVE_RESOLV_H
42 #include <resolv.h>
43 #endif
44 #ifdef HAVE_DNS_H
45 #include <dns.h>
46 #endif
47 #include "resolve.h"
48
49 #include <assert.h>
50
51 #ifdef _AIX /* AIX have broken res_nsearch() in 5.1 (5.0 also ?) */
52 #undef HAVE_RES_NSEARCH
53 #endif
54
55 #define DECL(X) {#X, rk_ns_t_##X}
56
57 static struct stot{
58 const char *name;
59 int type;
60 }stot[] = {
61 DECL(a),
62 DECL(aaaa),
63 DECL(ns),
64 DECL(cname),
65 DECL(soa),
66 DECL(ptr),
67 DECL(mx),
68 DECL(txt),
69 DECL(afsdb),
70 DECL(sig),
71 DECL(key),
72 DECL(srv),
73 DECL(naptr),
74 DECL(sshfp),
75 DECL(ds),
76 {NULL, 0}
77 };
78
79 int _resolve_debug = 0;
80
81 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
rk_dns_string_to_type(const char * name)82 rk_dns_string_to_type(const char *name)
83 {
84 struct stot *p = stot;
85 for(p = stot; p->name; p++)
86 if(strcasecmp(name, p->name) == 0)
87 return p->type;
88 return -1;
89 }
90
91 ROKEN_LIB_FUNCTION const char * ROKEN_LIB_CALL
rk_dns_type_to_string(int type)92 rk_dns_type_to_string(int type)
93 {
94 struct stot *p = stot;
95 for(p = stot; p->name; p++)
96 if(type == p->type)
97 return p->name;
98 return NULL;
99 }
100
101 #if ((defined(HAVE_RES_SEARCH) || defined(HAVE_RES_NSEARCH)) && defined(HAVE_DN_EXPAND)) || defined(HAVE_WINDNS)
102
103 static void
dns_free_rr(struct rk_resource_record * rr)104 dns_free_rr(struct rk_resource_record *rr)
105 {
106 if(rr->domain)
107 free(rr->domain);
108 if(rr->u.data)
109 free(rr->u.data);
110 free(rr);
111 }
112
113 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
rk_dns_free_data(struct rk_dns_reply * r)114 rk_dns_free_data(struct rk_dns_reply *r)
115 {
116 struct rk_resource_record *rr;
117 if(r->q.domain)
118 free(r->q.domain);
119 for(rr = r->head; rr;){
120 struct rk_resource_record *tmp = rr;
121 rr = rr->next;
122 dns_free_rr(tmp);
123 }
124 free (r);
125 }
126
127 #ifndef HAVE_WINDNS
128
129 static int
parse_record(const unsigned char * data,const unsigned char * end_data,const unsigned char ** pp,struct rk_resource_record ** ret_rr)130 parse_record(const unsigned char *data, const unsigned char *end_data,
131 const unsigned char **pp, struct rk_resource_record **ret_rr)
132 {
133 struct rk_resource_record *rr;
134 int type, class, ttl;
135 unsigned size;
136 int status;
137 char host[MAXDNAME];
138 const unsigned char *p = *pp;
139
140 *ret_rr = NULL;
141
142 status = dn_expand(data, end_data, p, host, sizeof(host));
143 if(status < 0)
144 return -1;
145 if (p + status + 10 > end_data)
146 return -1;
147
148 p += status;
149 type = (p[0] << 8) | p[1];
150 p += 2;
151 class = (p[0] << 8) | p[1];
152 p += 2;
153 ttl = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
154 p += 4;
155 size = (p[0] << 8) | p[1];
156 p += 2;
157
158 if (p + size > end_data)
159 return -1;
160
161 rr = calloc(1, sizeof(*rr));
162 if(rr == NULL)
163 return -1;
164 rr->domain = strdup(host);
165 if(rr->domain == NULL) {
166 dns_free_rr(rr);
167 return -1;
168 }
169 rr->type = type;
170 rr->class = class;
171 rr->ttl = ttl;
172 rr->size = size;
173 switch(type){
174 case rk_ns_t_ns:
175 case rk_ns_t_cname:
176 case rk_ns_t_ptr:
177 status = dn_expand(data, end_data, p, host, sizeof(host));
178 if(status < 0) {
179 dns_free_rr(rr);
180 return -1;
181 }
182 rr->u.txt = strdup(host);
183 if(rr->u.txt == NULL) {
184 dns_free_rr(rr);
185 return -1;
186 }
187 break;
188 case rk_ns_t_mx:
189 case rk_ns_t_afsdb:{
190 size_t hostlen;
191
192 status = dn_expand(data, end_data, p + 2, host, sizeof(host));
193 if(status < 0){
194 dns_free_rr(rr);
195 return -1;
196 }
197 if ((size_t)status + 2 > size) {
198 dns_free_rr(rr);
199 return -1;
200 }
201
202 hostlen = strlen(host);
203 rr->u.mx = (struct mx_record*)malloc(sizeof(struct mx_record) +
204 hostlen);
205 if(rr->u.mx == NULL) {
206 dns_free_rr(rr);
207 return -1;
208 }
209 rr->u.mx->preference = (p[0] << 8) | p[1];
210 strlcpy(rr->u.mx->domain, host, hostlen + 1);
211 break;
212 }
213 case rk_ns_t_srv:{
214 size_t hostlen;
215 status = dn_expand(data, end_data, p + 6, host, sizeof(host));
216 if(status < 0){
217 dns_free_rr(rr);
218 return -1;
219 }
220 if ((size_t)status + 6 > size) {
221 dns_free_rr(rr);
222 return -1;
223 }
224
225 hostlen = strlen(host);
226 rr->u.srv =
227 (struct srv_record*)malloc(sizeof(struct srv_record) +
228 hostlen);
229 if(rr->u.srv == NULL) {
230 dns_free_rr(rr);
231 return -1;
232 }
233 rr->u.srv->priority = (p[0] << 8) | p[1];
234 rr->u.srv->weight = (p[2] << 8) | p[3];
235 rr->u.srv->port = (p[4] << 8) | p[5];
236 strlcpy(rr->u.srv->target, host, hostlen + 1);
237 break;
238 }
239 case rk_ns_t_txt:{
240 if(size == 0 || size < (unsigned)(*p + 1)) {
241 dns_free_rr(rr);
242 return -1;
243 }
244 rr->u.txt = (char*)malloc(*p + 1);
245 if(rr->u.txt == NULL) {
246 dns_free_rr(rr);
247 return -1;
248 }
249 strncpy(rr->u.txt, (const char*)(p + 1), *p);
250 rr->u.txt[*p] = '\0';
251 break;
252 }
253 case rk_ns_t_key : {
254 size_t key_len;
255
256 if (size < 4) {
257 dns_free_rr(rr);
258 return -1;
259 }
260
261 key_len = size - 4;
262 rr->u.key = malloc (sizeof(*rr->u.key) + key_len - 1);
263 if (rr->u.key == NULL) {
264 dns_free_rr(rr);
265 return -1;
266 }
267
268 rr->u.key->flags = (p[0] << 8) | p[1];
269 rr->u.key->protocol = p[2];
270 rr->u.key->algorithm = p[3];
271 rr->u.key->key_len = key_len;
272 memcpy (rr->u.key->key_data, p + 4, key_len);
273 break;
274 }
275 case rk_ns_t_sig : {
276 size_t sig_len, hostlen;
277
278 if(size <= 18) {
279 dns_free_rr(rr);
280 return -1;
281 }
282 status = dn_expand (data, end_data, p + 18, host, sizeof(host));
283 if (status < 0) {
284 dns_free_rr(rr);
285 return -1;
286 }
287 if ((size_t)status + 18 > size) {
288 dns_free_rr(rr);
289 return -1;
290 }
291
292 /* the signer name is placed after the sig_data, to make it
293 easy to free this structure; the size calculation below
294 includes the zero-termination if the structure itself.
295 don't you just love C?
296 */
297 sig_len = size - 18 - status;
298 hostlen = strlen(host);
299 rr->u.sig = malloc(sizeof(*rr->u.sig)
300 + hostlen + sig_len);
301 if (rr->u.sig == NULL) {
302 dns_free_rr(rr);
303 return -1;
304 }
305 rr->u.sig->type = (p[0] << 8) | p[1];
306 rr->u.sig->algorithm = p[2];
307 rr->u.sig->labels = p[3];
308 rr->u.sig->orig_ttl = (p[4] << 24) | (p[5] << 16)
309 | (p[6] << 8) | p[7];
310 rr->u.sig->sig_expiration = (p[8] << 24) | (p[9] << 16)
311 | (p[10] << 8) | p[11];
312 rr->u.sig->sig_inception = (p[12] << 24) | (p[13] << 16)
313 | (p[14] << 8) | p[15];
314 rr->u.sig->key_tag = (p[16] << 8) | p[17];
315 rr->u.sig->sig_len = sig_len;
316 memcpy (rr->u.sig->sig_data, p + 18 + status, sig_len);
317 rr->u.sig->signer = &rr->u.sig->sig_data[sig_len];
318 strlcpy(rr->u.sig->signer, host, hostlen + 1);
319 break;
320 }
321
322 case rk_ns_t_cert : {
323 size_t cert_len;
324
325 if (size < 5) {
326 dns_free_rr(rr);
327 return -1;
328 }
329
330 cert_len = size - 5;
331 rr->u.cert = malloc (sizeof(*rr->u.cert) + cert_len - 1);
332 if (rr->u.cert == NULL) {
333 dns_free_rr(rr);
334 return -1;
335 }
336
337 rr->u.cert->type = (p[0] << 8) | p[1];
338 rr->u.cert->tag = (p[2] << 8) | p[3];
339 rr->u.cert->algorithm = p[4];
340 rr->u.cert->cert_len = cert_len;
341 memcpy (rr->u.cert->cert_data, p + 5, cert_len);
342 break;
343 }
344 case rk_ns_t_sshfp : {
345 size_t sshfp_len;
346
347 if (size < 2) {
348 dns_free_rr(rr);
349 return -1;
350 }
351
352 sshfp_len = size - 2;
353
354 rr->u.sshfp = malloc (sizeof(*rr->u.sshfp) + sshfp_len - 1);
355 if (rr->u.sshfp == NULL) {
356 dns_free_rr(rr);
357 return -1;
358 }
359
360 rr->u.sshfp->algorithm = p[0];
361 rr->u.sshfp->type = p[1];
362 rr->u.sshfp->sshfp_len = sshfp_len;
363 memcpy (rr->u.sshfp->sshfp_data, p + 2, sshfp_len);
364 break;
365 }
366 case rk_ns_t_ds: {
367 size_t digest_len;
368
369 if (size < 4) {
370 dns_free_rr(rr);
371 return -1;
372 }
373
374 digest_len = size - 4;
375
376 rr->u.ds = malloc (sizeof(*rr->u.ds) + digest_len - 1);
377 if (rr->u.ds == NULL) {
378 dns_free_rr(rr);
379 return -1;
380 }
381
382 rr->u.ds->key_tag = (p[0] << 8) | p[1];
383 rr->u.ds->algorithm = p[2];
384 rr->u.ds->digest_type = p[3];
385 rr->u.ds->digest_len = digest_len;
386 memcpy (rr->u.ds->digest_data, p + 4, digest_len);
387 break;
388 }
389 default:
390 rr->u.data = (unsigned char*)malloc(size);
391 if(size != 0 && rr->u.data == NULL) {
392 dns_free_rr(rr);
393 return -1;
394 }
395 if (size)
396 memcpy(rr->u.data, p, size);
397 }
398 *pp = p + size;
399 *ret_rr = rr;
400
401 return 0;
402 }
403
404 #ifndef TEST_RESOLVE
405 static
406 #endif
407 struct rk_dns_reply*
parse_reply(const unsigned char * data,size_t len)408 parse_reply(const unsigned char *data, size_t len)
409 {
410 const unsigned char *p;
411 int status;
412 size_t i;
413 char host[MAXDNAME];
414 const unsigned char *end_data = data + len;
415 struct rk_dns_reply *r;
416 struct rk_resource_record **rr;
417
418 r = calloc(1, sizeof(*r));
419 if (r == NULL)
420 return NULL;
421
422 p = data;
423
424 r->h.id = (p[0] << 8) | p[1];
425 r->h.flags = 0;
426 if (p[2] & 0x01)
427 r->h.flags |= rk_DNS_HEADER_RESPONSE_FLAG;
428 r->h.opcode = (p[2] >> 1) & 0xf;
429 if (p[2] & 0x20)
430 r->h.flags |= rk_DNS_HEADER_AUTHORITIVE_ANSWER;
431 if (p[2] & 0x40)
432 r->h.flags |= rk_DNS_HEADER_TRUNCATED_MESSAGE;
433 if (p[2] & 0x80)
434 r->h.flags |= rk_DNS_HEADER_RECURSION_DESIRED;
435 if (p[3] & 0x01)
436 r->h.flags |= rk_DNS_HEADER_RECURSION_AVAILABLE;
437 if (p[3] & 0x04)
438 r->h.flags |= rk_DNS_HEADER_AUTHORITIVE_ANSWER;
439 if (p[3] & 0x08)
440 r->h.flags |= rk_DNS_HEADER_CHECKING_DISABLED;
441 r->h.response_code = (p[3] >> 4) & 0xf;
442 r->h.qdcount = (p[4] << 8) | p[5];
443 r->h.ancount = (p[6] << 8) | p[7];
444 r->h.nscount = (p[8] << 8) | p[9];
445 r->h.arcount = (p[10] << 8) | p[11];
446
447 p += 12;
448
449 if(r->h.qdcount != 1) {
450 free(r);
451 return NULL;
452 }
453 status = dn_expand(data, end_data, p, host, sizeof(host));
454 if(status < 0){
455 rk_dns_free_data(r);
456 return NULL;
457 }
458 r->q.domain = strdup(host);
459 if(r->q.domain == NULL) {
460 rk_dns_free_data(r);
461 return NULL;
462 }
463 if (p + status + 4 > end_data) {
464 rk_dns_free_data(r);
465 return NULL;
466 }
467 p += status;
468 r->q.type = (p[0] << 8 | p[1]);
469 p += 2;
470 r->q.class = (p[0] << 8 | p[1]);
471 p += 2;
472
473 rr = &r->head;
474 for(i = 0; i < r->h.ancount; i++) {
475 if(parse_record(data, end_data, &p, rr) != 0) {
476 rk_dns_free_data(r);
477 return NULL;
478 }
479 rr = &(*rr)->next;
480 }
481 for(i = 0; i < r->h.nscount; i++) {
482 if(parse_record(data, end_data, &p, rr) != 0) {
483 rk_dns_free_data(r);
484 return NULL;
485 }
486 rr = &(*rr)->next;
487 }
488 for(i = 0; i < r->h.arcount; i++) {
489 if(parse_record(data, end_data, &p, rr) != 0) {
490 rk_dns_free_data(r);
491 return NULL;
492 }
493 rr = &(*rr)->next;
494 }
495 *rr = NULL;
496 return r;
497 }
498
499 #ifdef HAVE_RES_NSEARCH
500 #ifdef HAVE_RES_NDESTROY
501 #define rk_res_free(x) res_ndestroy(x)
502 #else
503 #define rk_res_free(x) res_nclose(x)
504 #endif
505 #endif
506
507 #if defined(HAVE_DNS_SEARCH)
508 #define resolve_search(h,n,c,t,r,l) \
509 ((int)dns_search(h,n,c,t,r,l,(struct sockaddr *)&from,&fromsize))
510 #define resolve_free_handle(h) dns_free(h)
511 #elif defined(HAVE_RES_NSEARCH)
512 #define resolve_search(h,n,c,t,r,l) res_nsearch(h,n,c,t,r,l)
513 #define resolve_free_handle(h) rk_res_free(h);
514 #else
515 #define resolve_search(h,n,c,t,r,l) res_search(n,c,t,r,l)
516 #define handle 0
517 #define resolve_free_handle(h)
518 #endif
519
520
521 static struct rk_dns_reply *
dns_lookup_int(const char * domain,int rr_class,int rr_type)522 dns_lookup_int(const char *domain, int rr_class, int rr_type)
523 {
524 struct rk_dns_reply *r;
525 void *reply = NULL;
526 int size, len;
527 #if defined(HAVE_DNS_SEARCH)
528 struct sockaddr_storage from;
529 uint32_t fromsize = sizeof(from);
530 dns_handle_t handle;
531
532 handle = dns_open(NULL);
533 if (handle == NULL)
534 return NULL;
535 #elif defined(HAVE_RES_NSEARCH)
536 struct __res_state state;
537 struct __res_state *handle = &state;
538
539 memset(&state, 0, sizeof(state));
540 if(res_ninit(handle))
541 return NULL; /* is this the best we can do? */
542 #endif
543
544 len = 1500;
545 while(1) {
546 if (reply) {
547 free(reply);
548 reply = NULL;
549 }
550 if (_resolve_debug) {
551 #if defined(HAVE_DNS_SEARCH)
552 dns_set_debug(handle, 1);
553 #elif defined(HAVE_RES_NSEARCH)
554 state.options |= RES_DEBUG;
555 #endif
556 fprintf(stderr, "dns_lookup(%s, %d, %s), buffer size %d\n", domain,
557 rr_class, rk_dns_type_to_string(rr_type), len);
558 }
559 reply = malloc(len);
560 if (reply == NULL) {
561 resolve_free_handle(handle);
562 return NULL;
563 }
564
565 size = resolve_search(handle, domain, rr_class, rr_type, reply, len);
566
567 if (_resolve_debug) {
568 fprintf(stderr, "dns_lookup(%s, %d, %s) --> %d\n",
569 domain, rr_class, rk_dns_type_to_string(rr_type), size);
570 }
571 if (size > len) {
572 /* resolver thinks it know better, go for it */
573 len = size;
574 } else if (size > 0) {
575 /* got a good reply */
576 break;
577 } else if (size <= 0 && len < rk_DNS_MAX_PACKET_SIZE) {
578 len *= 2;
579 if (len > rk_DNS_MAX_PACKET_SIZE)
580 len = rk_DNS_MAX_PACKET_SIZE;
581 } else {
582 /* the end, leave */
583 resolve_free_handle(handle);
584 free(reply);
585 return NULL;
586 }
587 }
588
589 len = min(len, size);
590 r = parse_reply(reply, len);
591 free(reply);
592
593 resolve_free_handle(handle);
594
595 return r;
596 }
597
598 ROKEN_LIB_FUNCTION struct rk_dns_reply * ROKEN_LIB_CALL
rk_dns_lookup(const char * domain,const char * type_name)599 rk_dns_lookup(const char *domain, const char *type_name)
600 {
601 int type;
602
603 type = rk_dns_string_to_type(type_name);
604 if(type == -1) {
605 if(_resolve_debug)
606 fprintf(stderr, "dns_lookup: unknown resource type: `%s'\n",
607 type_name);
608 return NULL;
609 }
610 return dns_lookup_int(domain, rk_ns_c_in, type);
611 }
612
613 #endif /* !HAVE_WINDNS */
614
615 static int
compare_srv(const void * a,const void * b)616 compare_srv(const void *a, const void *b)
617 {
618 const struct rk_resource_record *const* aa = a, *const* bb = b;
619
620 if((*aa)->u.srv->priority == (*bb)->u.srv->priority)
621 return ((*aa)->u.srv->weight - (*bb)->u.srv->weight);
622 return ((*aa)->u.srv->priority - (*bb)->u.srv->priority);
623 }
624
625 /* try to rearrange the srv-records by the algorithm in RFC2782 */
626 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
rk_dns_srv_order(struct rk_dns_reply * r)627 rk_dns_srv_order(struct rk_dns_reply *r)
628 {
629 struct rk_resource_record **srvs, **ss, **headp;
630 struct rk_resource_record *rr;
631 int num_srv = 0;
632
633 rk_random_init();
634
635 for(rr = r->head; rr; rr = rr->next)
636 if(rr->type == rk_ns_t_srv)
637 num_srv++;
638
639 if(num_srv == 0)
640 return;
641
642 srvs = malloc(num_srv * sizeof(*srvs));
643 if(srvs == NULL)
644 return; /* XXX not much to do here */
645
646 /* unlink all srv-records from the linked list and put them in
647 a vector */
648 for(ss = srvs, headp = &r->head; *headp; )
649 if((*headp)->type == rk_ns_t_srv) {
650 *ss = *headp;
651 *headp = (*headp)->next;
652 (*ss)->next = NULL;
653 ss++;
654 } else
655 headp = &(*headp)->next;
656
657 /* sort them by priority and weight */
658 qsort(srvs, num_srv, sizeof(*srvs), compare_srv);
659
660 headp = &r->head;
661
662 for(ss = srvs; ss < srvs + num_srv; ) {
663 int sum, rnd, count;
664 struct rk_resource_record **ee, **tt;
665 /* find the last record with the same priority and count the
666 sum of all weights */
667 for(sum = 0, tt = ss; tt < srvs + num_srv; tt++) {
668 assert(*tt != NULL);
669 if((*tt)->u.srv->priority != (*ss)->u.srv->priority)
670 break;
671 sum += (*tt)->u.srv->weight;
672 }
673 ee = tt;
674 /* ss is now the first record of this priority and ee is the
675 first of the next */
676 while(ss < ee) {
677 rnd = rk_random() % (sum + 1);
678 for(count = 0, tt = ss; ; tt++) {
679 if(*tt == NULL)
680 continue;
681 count += (*tt)->u.srv->weight;
682 if(count >= rnd)
683 break;
684 }
685
686 assert(tt < ee);
687
688 /* insert the selected record at the tail (of the head) of
689 the list */
690 (*tt)->next = *headp;
691 *headp = *tt;
692 headp = &(*tt)->next;
693 sum -= (*tt)->u.srv->weight;
694 *tt = NULL;
695 while(ss < ee && *ss == NULL)
696 ss++;
697 }
698 }
699
700 free(srvs);
701 return;
702 }
703
704 #ifdef HAVE_WINDNS
705
706 #include <WinDNS.h>
707
708 static struct rk_resource_record *
parse_dns_record(PDNS_RECORD pRec)709 parse_dns_record(PDNS_RECORD pRec)
710 {
711 struct rk_resource_record * rr;
712
713 if (pRec == NULL)
714 return NULL;
715
716 rr = calloc(1, sizeof(*rr));
717
718 rr->domain = strdup(pRec->pName);
719 rr->type = pRec->wType;
720 rr->class = 0;
721 rr->ttl = pRec->dwTtl;
722 rr->size = 0;
723
724 switch (rr->type) {
725 case rk_ns_t_ns:
726 case rk_ns_t_cname:
727 case rk_ns_t_ptr:
728 rr->u.txt = strdup(pRec->Data.NS.pNameHost);
729 if(rr->u.txt == NULL) {
730 dns_free_rr(rr);
731 return NULL;
732 }
733 break;
734
735 case rk_ns_t_mx:
736 case rk_ns_t_afsdb:{
737 size_t hostlen = strnlen(pRec->Data.MX.pNameExchange, DNS_MAX_NAME_LENGTH);
738
739 rr->u.mx = (struct mx_record *)malloc(sizeof(struct mx_record) +
740 hostlen);
741 if (rr->u.mx == NULL) {
742 dns_free_rr(rr);
743 return NULL;
744 }
745
746 strcpy_s(rr->u.mx->domain, hostlen + 1, pRec->Data.MX.pNameExchange);
747 rr->u.mx->preference = pRec->Data.MX.wPreference;
748 break;
749 }
750
751 case rk_ns_t_srv:{
752 size_t hostlen = strnlen(pRec->Data.SRV.pNameTarget, DNS_MAX_NAME_LENGTH);
753
754 rr->u.srv =
755 (struct srv_record*)malloc(sizeof(struct srv_record) +
756 hostlen);
757 if(rr->u.srv == NULL) {
758 dns_free_rr(rr);
759 return NULL;
760 }
761
762 rr->u.srv->priority = pRec->Data.SRV.wPriority;
763 rr->u.srv->weight = pRec->Data.SRV.wWeight;
764 rr->u.srv->port = pRec->Data.SRV.wPort;
765 strcpy_s(rr->u.srv->target, hostlen + 1, pRec->Data.SRV.pNameTarget);
766
767 break;
768 }
769
770 case rk_ns_t_txt:{
771 size_t len;
772
773 if (pRec->Data.TXT.dwStringCount == 0) {
774 rr->u.txt = strdup("");
775 break;
776 }
777
778 len = strnlen(pRec->Data.TXT.pStringArray[0], DNS_MAX_TEXT_STRING_LENGTH);
779
780 rr->u.txt = (char *)malloc(len + 1);
781 strcpy_s(rr->u.txt, len + 1, pRec->Data.TXT.pStringArray[0]);
782
783 break;
784 }
785
786 case rk_ns_t_key : {
787 size_t key_len;
788
789 if (pRec->wDataLength < 4) {
790 dns_free_rr(rr);
791 return NULL;
792 }
793
794 key_len = pRec->wDataLength - 4;
795 rr->u.key = malloc (sizeof(*rr->u.key) + key_len - 1);
796 if (rr->u.key == NULL) {
797 dns_free_rr(rr);
798 return NULL;
799 }
800
801 rr->u.key->flags = pRec->Data.KEY.wFlags;
802 rr->u.key->protocol = pRec->Data.KEY.chProtocol;
803 rr->u.key->algorithm = pRec->Data.KEY.chAlgorithm;
804 rr->u.key->key_len = key_len;
805 memcpy_s (rr->u.key->key_data, key_len,
806 pRec->Data.KEY.Key, key_len);
807 break;
808 }
809
810 case rk_ns_t_sig : {
811 size_t sig_len, hostlen;
812
813 if(pRec->wDataLength <= 18) {
814 dns_free_rr(rr);
815 return NULL;
816 }
817
818 sig_len = pRec->wDataLength;
819
820 hostlen = strnlen(pRec->Data.SIG.pNameSigner, DNS_MAX_NAME_LENGTH);
821
822 rr->u.sig = malloc(sizeof(*rr->u.sig)
823 + hostlen + sig_len);
824 if (rr->u.sig == NULL) {
825 dns_free_rr(rr);
826 return NULL;
827 }
828 rr->u.sig->type = pRec->Data.SIG.wTypeCovered;
829 rr->u.sig->algorithm = pRec->Data.SIG.chAlgorithm;
830 rr->u.sig->labels = pRec->Data.SIG.chLabelCount;
831 rr->u.sig->orig_ttl = pRec->Data.SIG.dwOriginalTtl;
832 rr->u.sig->sig_expiration = pRec->Data.SIG.dwExpiration;
833 rr->u.sig->sig_inception = pRec->Data.SIG.dwTimeSigned;
834 rr->u.sig->key_tag = pRec->Data.SIG.wKeyTag;
835 rr->u.sig->sig_len = sig_len;
836 memcpy_s (rr->u.sig->sig_data, sig_len,
837 pRec->Data.SIG.Signature, sig_len);
838 rr->u.sig->signer = &rr->u.sig->sig_data[sig_len];
839 strcpy_s(rr->u.sig->signer, hostlen + 1, pRec->Data.SIG.pNameSigner);
840 break;
841 }
842
843 #ifdef DNS_TYPE_DS
844 case rk_ns_t_ds: {
845 rr->u.ds = malloc (sizeof(*rr->u.ds) + pRec->Data.DS.wDigestLength - 1);
846 if (rr->u.ds == NULL) {
847 dns_free_rr(rr);
848 return NULL;
849 }
850
851 rr->u.ds->key_tag = pRec->Data.DS.wKeyTag;
852 rr->u.ds->algorithm = pRec->Data.DS.chAlgorithm;
853 rr->u.ds->digest_type = pRec->Data.DS.chDigestType;
854 rr->u.ds->digest_len = pRec->Data.DS.wDigestLength;
855 memcpy_s (rr->u.ds->digest_data, pRec->Data.DS.wDigestLength,
856 pRec->Data.DS.Digest, pRec->Data.DS.wDigestLength);
857 break;
858 }
859 #endif
860
861 default:
862 dns_free_rr(rr);
863 return NULL;
864 }
865
866 rr->next = parse_dns_record(pRec->pNext);
867 return rr;
868 }
869
870 ROKEN_LIB_FUNCTION struct rk_dns_reply * ROKEN_LIB_CALL
rk_dns_lookup(const char * domain,const char * type_name)871 rk_dns_lookup(const char *domain, const char *type_name)
872 {
873 DNS_STATUS status;
874 int type;
875 PDNS_RECORD pRec = NULL;
876 struct rk_dns_reply * r = NULL;
877
878 __try {
879
880 type = rk_dns_string_to_type(type_name);
881 if(type == -1) {
882 if(_resolve_debug)
883 fprintf(stderr, "dns_lookup: unknown resource type: `%s'\n",
884 type_name);
885 return NULL;
886 }
887
888 status = DnsQuery_UTF8(domain, type, DNS_QUERY_STANDARD, NULL,
889 &pRec, NULL);
890 if (status != ERROR_SUCCESS)
891 return NULL;
892
893 r = calloc(1, sizeof(*r));
894 r->q.domain = strdup(domain);
895 r->q.type = type;
896 r->q.class = 0;
897
898 r->head = parse_dns_record(pRec);
899
900 if (r->head == NULL) {
901 rk_dns_free_data(r);
902 return NULL;
903 } else {
904 return r;
905 }
906
907 } __finally {
908
909 if (pRec)
910 DnsRecordListFree(pRec, DnsFreeRecordList);
911
912 }
913 }
914 #endif /* HAVE_WINDNS */
915
916 #else /* NOT defined(HAVE_RES_SEARCH) && defined(HAVE_DN_EXPAND) */
917
918 ROKEN_LIB_FUNCTION struct rk_dns_reply * ROKEN_LIB_CALL
rk_dns_lookup(const char * domain,const char * type_name)919 rk_dns_lookup(const char *domain, const char *type_name)
920 {
921 return NULL;
922 }
923
924 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
rk_dns_free_data(struct rk_dns_reply * r)925 rk_dns_free_data(struct rk_dns_reply *r)
926 {
927 }
928
929 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
rk_dns_srv_order(struct rk_dns_reply * r)930 rk_dns_srv_order(struct rk_dns_reply *r)
931 {
932 }
933
934 #endif
935