diff options
Diffstat (limited to 'src/lib/libc/net/getrrsetbyname.c')
-rw-r--r-- | src/lib/libc/net/getrrsetbyname.c | 512 |
1 files changed, 512 insertions, 0 deletions
diff --git a/src/lib/libc/net/getrrsetbyname.c b/src/lib/libc/net/getrrsetbyname.c new file mode 100644 index 0000000000..f00ac2b021 --- /dev/null +++ b/src/lib/libc/net/getrrsetbyname.c | |||
@@ -0,0 +1,512 @@ | |||
1 | /* $OpenBSD: getrrsetbyname.c,v 1.7 2003/03/07 07:34:14 itojun Exp $ */ | ||
2 | |||
3 | /* | ||
4 | * Copyright (c) 2001 Jakob Schlyter. 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 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | ||
18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | ||
19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | ||
20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | ||
21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | ||
22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | ||
23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | ||
24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | ||
25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | ||
26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | ||
27 | */ | ||
28 | |||
29 | /* | ||
30 | * Portions Copyright (c) 1999-2001 Internet Software Consortium. | ||
31 | * | ||
32 | * Permission to use, copy, modify, and distribute this software for any | ||
33 | * purpose with or without fee is hereby granted, provided that the above | ||
34 | * copyright notice and this permission notice appear in all copies. | ||
35 | * | ||
36 | * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM | ||
37 | * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL | ||
38 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL | ||
39 | * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, | ||
40 | * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING | ||
41 | * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, | ||
42 | * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION | ||
43 | * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. | ||
44 | */ | ||
45 | |||
46 | #include <sys/types.h> | ||
47 | #include <netinet/in.h> | ||
48 | #include <arpa/nameser.h> | ||
49 | #include <netdb.h> | ||
50 | #include <resolv.h> | ||
51 | #include <stdlib.h> | ||
52 | #include <string.h> | ||
53 | |||
54 | #include "thread_private.h" | ||
55 | |||
56 | #define ANSWER_BUFFER_SIZE 1024*64 | ||
57 | |||
58 | struct dns_query { | ||
59 | char *name; | ||
60 | u_int16_t type; | ||
61 | u_int16_t class; | ||
62 | struct dns_query *next; | ||
63 | }; | ||
64 | |||
65 | struct dns_rr { | ||
66 | char *name; | ||
67 | u_int16_t type; | ||
68 | u_int16_t class; | ||
69 | u_int16_t ttl; | ||
70 | u_int16_t size; | ||
71 | void *rdata; | ||
72 | struct dns_rr *next; | ||
73 | }; | ||
74 | |||
75 | struct dns_response { | ||
76 | HEADER header; | ||
77 | struct dns_query *query; | ||
78 | struct dns_rr *answer; | ||
79 | struct dns_rr *authority; | ||
80 | struct dns_rr *additional; | ||
81 | }; | ||
82 | |||
83 | static struct dns_response *parse_dns_response(const u_char *, int); | ||
84 | static struct dns_query *parse_dns_qsection(const u_char *, int, | ||
85 | const u_char **, int); | ||
86 | static struct dns_rr *parse_dns_rrsection(const u_char *, int, const u_char **, | ||
87 | int); | ||
88 | |||
89 | static void free_dns_query(struct dns_query *); | ||
90 | static void free_dns_rr(struct dns_rr *); | ||
91 | static void free_dns_response(struct dns_response *); | ||
92 | |||
93 | static int count_dns_rr(struct dns_rr *, u_int16_t, u_int16_t); | ||
94 | |||
95 | int | ||
96 | getrrsetbyname(const char *hostname, unsigned int rdclass, | ||
97 | unsigned int rdtype, unsigned int flags, | ||
98 | struct rrsetinfo **res) | ||
99 | { | ||
100 | struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res); | ||
101 | int result; | ||
102 | struct rrsetinfo *rrset = NULL; | ||
103 | struct dns_response *response; | ||
104 | struct dns_rr *rr; | ||
105 | struct rdatainfo *rdata; | ||
106 | int length; | ||
107 | unsigned int index_ans, index_sig; | ||
108 | u_char answer[ANSWER_BUFFER_SIZE]; | ||
109 | |||
110 | /* check for invalid class and type */ | ||
111 | if (rdclass > 0xffff || rdtype > 0xffff) { | ||
112 | result = ERRSET_INVAL; | ||
113 | goto fail; | ||
114 | } | ||
115 | |||
116 | /* don't allow queries of class or type ANY */ | ||
117 | if (rdclass == 0xff || rdtype == 0xff) { | ||
118 | result = ERRSET_INVAL; | ||
119 | goto fail; | ||
120 | } | ||
121 | |||
122 | /* don't allow flags yet, unimplemented */ | ||
123 | if (flags) { | ||
124 | result = ERRSET_INVAL; | ||
125 | goto fail; | ||
126 | } | ||
127 | |||
128 | /* initialize resolver */ | ||
129 | if ((_resp->options & RES_INIT) == 0 && res_init() == -1) { | ||
130 | result = ERRSET_FAIL; | ||
131 | goto fail; | ||
132 | } | ||
133 | |||
134 | #ifdef DEBUG | ||
135 | _resp->options |= RES_DEBUG; | ||
136 | #endif /* DEBUG */ | ||
137 | |||
138 | #ifdef RES_USE_DNSSEC | ||
139 | /* turn on DNSSEC if EDNS0 is configured */ | ||
140 | if (_resp->options & RES_USE_EDNS0) | ||
141 | _resp->options |= RES_USE_DNSSEC; | ||
142 | #endif /* RES_USE_DNSEC */ | ||
143 | |||
144 | /* make query */ | ||
145 | length = res_query(hostname, (signed int) rdclass, (signed int) rdtype, | ||
146 | answer, sizeof(answer)); | ||
147 | if (length < 0) { | ||
148 | switch(h_errno) { | ||
149 | case HOST_NOT_FOUND: | ||
150 | result = ERRSET_NONAME; | ||
151 | goto fail; | ||
152 | case NO_DATA: | ||
153 | result = ERRSET_NODATA; | ||
154 | goto fail; | ||
155 | default: | ||
156 | result = ERRSET_FAIL; | ||
157 | goto fail; | ||
158 | } | ||
159 | } | ||
160 | |||
161 | /* parse result */ | ||
162 | response = parse_dns_response(answer, length); | ||
163 | if (response == NULL) { | ||
164 | result = ERRSET_FAIL; | ||
165 | goto fail; | ||
166 | } | ||
167 | |||
168 | if (response->header.qdcount != 1) { | ||
169 | result = ERRSET_FAIL; | ||
170 | goto fail; | ||
171 | } | ||
172 | |||
173 | /* initialize rrset */ | ||
174 | rrset = calloc(1, sizeof(struct rrsetinfo)); | ||
175 | if (rrset == NULL) { | ||
176 | result = ERRSET_NOMEMORY; | ||
177 | goto fail; | ||
178 | } | ||
179 | rrset->rri_rdclass = response->query->class; | ||
180 | rrset->rri_rdtype = response->query->type; | ||
181 | rrset->rri_ttl = response->answer->ttl; | ||
182 | rrset->rri_nrdatas = response->header.ancount; | ||
183 | |||
184 | /* check for authenticated data */ | ||
185 | if (response->header.ad == 1) | ||
186 | rrset->rri_flags |= RRSET_VALIDATED; | ||
187 | |||
188 | /* copy name from answer section */ | ||
189 | length = strlen(response->answer->name); | ||
190 | rrset->rri_name = malloc(length + 1); | ||
191 | if (rrset->rri_name == NULL) { | ||
192 | result = ERRSET_NOMEMORY; | ||
193 | goto fail; | ||
194 | } | ||
195 | strlcpy(rrset->rri_name, response->answer->name, length + 1); | ||
196 | |||
197 | /* count answers */ | ||
198 | rrset->rri_nrdatas = count_dns_rr(response->answer, rrset->rri_rdclass, | ||
199 | rrset->rri_rdtype); | ||
200 | rrset->rri_nsigs = count_dns_rr(response->answer, rrset->rri_rdclass, | ||
201 | T_SIG); | ||
202 | |||
203 | /* allocate memory for answers */ | ||
204 | rrset->rri_rdatas = calloc(rrset->rri_nrdatas, | ||
205 | sizeof(struct rdatainfo)); | ||
206 | if (rrset->rri_rdatas == NULL) { | ||
207 | result = ERRSET_NOMEMORY; | ||
208 | goto fail; | ||
209 | } | ||
210 | |||
211 | /* allocate memory for signatures */ | ||
212 | rrset->rri_sigs = calloc(rrset->rri_nsigs, sizeof(struct rdatainfo)); | ||
213 | if (rrset->rri_sigs == NULL) { | ||
214 | result = ERRSET_NOMEMORY; | ||
215 | goto fail; | ||
216 | } | ||
217 | |||
218 | /* copy answers & signatures */ | ||
219 | for (rr = response->answer, index_ans = 0, index_sig = 0; | ||
220 | rr; rr = rr->next) { | ||
221 | |||
222 | rdata = NULL; | ||
223 | |||
224 | if (rr->class == rrset->rri_rdclass && | ||
225 | rr->type == rrset->rri_rdtype) | ||
226 | rdata = &rrset->rri_rdatas[index_ans++]; | ||
227 | |||
228 | if (rr->class == rrset->rri_rdclass && | ||
229 | rr->type == T_SIG) | ||
230 | rdata = &rrset->rri_sigs[index_sig++]; | ||
231 | |||
232 | if (rdata) { | ||
233 | rdata->rdi_length = rr->size; | ||
234 | rdata->rdi_data = malloc(rr->size); | ||
235 | |||
236 | if (rdata->rdi_data == NULL) { | ||
237 | result = ERRSET_NOMEMORY; | ||
238 | goto fail; | ||
239 | } | ||
240 | memcpy(rdata->rdi_data, rr->rdata, rr->size); | ||
241 | } | ||
242 | } | ||
243 | |||
244 | *res = rrset; | ||
245 | return (ERRSET_SUCCESS); | ||
246 | |||
247 | fail: | ||
248 | if (rrset != NULL) | ||
249 | freerrset(rrset); | ||
250 | return (result); | ||
251 | } | ||
252 | |||
253 | void | ||
254 | freerrset(struct rrsetinfo *rrset) | ||
255 | { | ||
256 | u_int16_t i; | ||
257 | |||
258 | if (rrset == NULL) | ||
259 | return; | ||
260 | |||
261 | if (rrset->rri_rdatas) { | ||
262 | for (i = 0; i < rrset->rri_nrdatas; i++) { | ||
263 | if (rrset->rri_rdatas[i].rdi_data == NULL) | ||
264 | break; | ||
265 | free(rrset->rri_rdatas[i].rdi_data); | ||
266 | } | ||
267 | free(rrset->rri_rdatas); | ||
268 | } | ||
269 | |||
270 | if (rrset->rri_sigs) { | ||
271 | for (i = 0; i < rrset->rri_nsigs; i++) { | ||
272 | if (rrset->rri_sigs[i].rdi_data == NULL) | ||
273 | break; | ||
274 | free(rrset->rri_sigs[i].rdi_data); | ||
275 | } | ||
276 | free(rrset->rri_sigs); | ||
277 | } | ||
278 | |||
279 | if (rrset->rri_name) | ||
280 | free(rrset->rri_name); | ||
281 | free(rrset); | ||
282 | } | ||
283 | |||
284 | /* | ||
285 | * DNS response parsing routines | ||
286 | */ | ||
287 | static struct dns_response * | ||
288 | parse_dns_response(const u_char *answer, int size) | ||
289 | { | ||
290 | struct dns_response *resp; | ||
291 | const u_char *cp; | ||
292 | |||
293 | /* allocate memory for the response */ | ||
294 | resp = calloc(1, sizeof(*resp)); | ||
295 | if (resp == NULL) | ||
296 | return (NULL); | ||
297 | |||
298 | /* initialize current pointer */ | ||
299 | cp = answer; | ||
300 | |||
301 | /* copy header */ | ||
302 | memcpy(&resp->header, cp, HFIXEDSZ); | ||
303 | cp += HFIXEDSZ; | ||
304 | |||
305 | /* fix header byte order */ | ||
306 | resp->header.qdcount = ntohs(resp->header.qdcount); | ||
307 | resp->header.ancount = ntohs(resp->header.ancount); | ||
308 | resp->header.nscount = ntohs(resp->header.nscount); | ||
309 | resp->header.arcount = ntohs(resp->header.arcount); | ||
310 | |||
311 | /* there must be at least one query */ | ||
312 | if (resp->header.qdcount < 1) { | ||
313 | free_dns_response(resp); | ||
314 | return (NULL); | ||
315 | } | ||
316 | |||
317 | /* parse query section */ | ||
318 | resp->query = parse_dns_qsection(answer, size, &cp, | ||
319 | resp->header.qdcount); | ||
320 | if (resp->header.qdcount && resp->query == NULL) { | ||
321 | free_dns_response(resp); | ||
322 | return (NULL); | ||
323 | } | ||
324 | |||
325 | /* parse answer section */ | ||
326 | resp->answer = parse_dns_rrsection(answer, size, &cp, | ||
327 | resp->header.ancount); | ||
328 | if (resp->header.ancount && resp->answer == NULL) { | ||
329 | free_dns_response(resp); | ||
330 | return (NULL); | ||
331 | } | ||
332 | |||
333 | /* parse authority section */ | ||
334 | resp->authority = parse_dns_rrsection(answer, size, &cp, | ||
335 | resp->header.nscount); | ||
336 | if (resp->header.nscount && resp->authority == NULL) { | ||
337 | free_dns_response(resp); | ||
338 | return (NULL); | ||
339 | } | ||
340 | |||
341 | /* parse additional section */ | ||
342 | resp->additional = parse_dns_rrsection(answer, size, &cp, | ||
343 | resp->header.arcount); | ||
344 | if (resp->header.arcount && resp->additional == NULL) { | ||
345 | free_dns_response(resp); | ||
346 | return (NULL); | ||
347 | } | ||
348 | |||
349 | return (resp); | ||
350 | } | ||
351 | |||
352 | static struct dns_query * | ||
353 | parse_dns_qsection(const u_char *answer, int size, const u_char **cp, int count) | ||
354 | { | ||
355 | struct dns_query *head, *curr, *prev; | ||
356 | int i, length; | ||
357 | char name[MAXDNAME]; | ||
358 | |||
359 | for (i = 1, head = NULL, prev = NULL; i <= count; i++, prev = curr) { | ||
360 | |||
361 | /* allocate and initialize struct */ | ||
362 | curr = calloc(1, sizeof(struct dns_query)); | ||
363 | if (curr == NULL) { | ||
364 | free_dns_query(head); | ||
365 | return (NULL); | ||
366 | } | ||
367 | if (head == NULL) | ||
368 | head = curr; | ||
369 | if (prev != NULL) | ||
370 | prev->next = curr; | ||
371 | |||
372 | /* name */ | ||
373 | length = dn_expand(answer, answer + size, *cp, name, | ||
374 | sizeof(name)); | ||
375 | if (length < 0) { | ||
376 | free_dns_query(head); | ||
377 | return (NULL); | ||
378 | } | ||
379 | curr->name = strdup(name); | ||
380 | if (curr->name == NULL) { | ||
381 | free_dns_query(head); | ||
382 | return (NULL); | ||
383 | } | ||
384 | *cp += length; | ||
385 | |||
386 | /* type */ | ||
387 | curr->type = _getshort(*cp); | ||
388 | *cp += INT16SZ; | ||
389 | |||
390 | /* class */ | ||
391 | curr->class = _getshort(*cp); | ||
392 | *cp += INT16SZ; | ||
393 | } | ||
394 | |||
395 | return (head); | ||
396 | } | ||
397 | |||
398 | static struct dns_rr * | ||
399 | parse_dns_rrsection(const u_char *answer, int size, const u_char **cp, int count) | ||
400 | { | ||
401 | struct dns_rr *head, *curr, *prev; | ||
402 | int i, length; | ||
403 | char name[MAXDNAME]; | ||
404 | |||
405 | for (i = 1, head = NULL, prev = NULL; i <= count; i++, prev = curr) { | ||
406 | |||
407 | /* allocate and initialize struct */ | ||
408 | curr = calloc(1, sizeof(struct dns_rr)); | ||
409 | if (curr == NULL) { | ||
410 | free_dns_rr(head); | ||
411 | return (NULL); | ||
412 | } | ||
413 | if (head == NULL) | ||
414 | head = curr; | ||
415 | if (prev != NULL) | ||
416 | prev->next = curr; | ||
417 | |||
418 | /* name */ | ||
419 | length = dn_expand(answer, answer + size, *cp, name, | ||
420 | sizeof(name)); | ||
421 | if (length < 0) { | ||
422 | free_dns_rr(head); | ||
423 | return (NULL); | ||
424 | } | ||
425 | curr->name = strdup(name); | ||
426 | if (curr->name == NULL) { | ||
427 | free_dns_rr(head); | ||
428 | return (NULL); | ||
429 | } | ||
430 | *cp += length; | ||
431 | |||
432 | /* type */ | ||
433 | curr->type = _getshort(*cp); | ||
434 | *cp += INT16SZ; | ||
435 | |||
436 | /* class */ | ||
437 | curr->class = _getshort(*cp); | ||
438 | *cp += INT16SZ; | ||
439 | |||
440 | /* ttl */ | ||
441 | curr->ttl = _getlong(*cp); | ||
442 | *cp += INT32SZ; | ||
443 | |||
444 | /* rdata size */ | ||
445 | curr->size = _getshort(*cp); | ||
446 | *cp += INT16SZ; | ||
447 | |||
448 | /* rdata itself */ | ||
449 | curr->rdata = malloc(curr->size); | ||
450 | if (curr->rdata == NULL) { | ||
451 | free_dns_rr(head); | ||
452 | return (NULL); | ||
453 | } | ||
454 | memcpy(curr->rdata, *cp, curr->size); | ||
455 | *cp += curr->size; | ||
456 | } | ||
457 | |||
458 | return (head); | ||
459 | } | ||
460 | |||
461 | static void | ||
462 | free_dns_query(struct dns_query *p) | ||
463 | { | ||
464 | if (p == NULL) | ||
465 | return; | ||
466 | |||
467 | if (p->name) | ||
468 | free(p->name); | ||
469 | free_dns_query(p->next); | ||
470 | free(p); | ||
471 | } | ||
472 | |||
473 | static void | ||
474 | free_dns_rr(struct dns_rr *p) | ||
475 | { | ||
476 | if (p == NULL) | ||
477 | return; | ||
478 | |||
479 | if (p->name) | ||
480 | free(p->name); | ||
481 | if (p->rdata) | ||
482 | free(p->rdata); | ||
483 | free_dns_rr(p->next); | ||
484 | free(p); | ||
485 | } | ||
486 | |||
487 | static void | ||
488 | free_dns_response(struct dns_response *p) | ||
489 | { | ||
490 | if (p == NULL) | ||
491 | return; | ||
492 | |||
493 | free_dns_query(p->query); | ||
494 | free_dns_rr(p->answer); | ||
495 | free_dns_rr(p->authority); | ||
496 | free_dns_rr(p->additional); | ||
497 | free(p); | ||
498 | } | ||
499 | |||
500 | static int | ||
501 | count_dns_rr(struct dns_rr *p, u_int16_t class, u_int16_t type) | ||
502 | { | ||
503 | int n = 0; | ||
504 | |||
505 | while(p) { | ||
506 | if (p->class == class && p->type == type) | ||
507 | n++; | ||
508 | p = p->next; | ||
509 | } | ||
510 | |||
511 | return (n); | ||
512 | } | ||