1 /*-
2 * SPDX-License-Identifier: (BSD-3-Clause AND ISC)
3 *
4 * Copyright (c) 1985, 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 /*
33 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
34 *
35 * Permission to use, copy, modify, and distribute this software for any
36 * purpose with or without fee is hereby granted, provided that the above
37 * copyright notice and this permission notice appear in all copies, and that
38 * the name of Digital Equipment Corporation not be used in advertising or
39 * publicity pertaining to distribution of the document or software without
40 * specific, written prior permission.
41 *
42 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
43 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
44 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
45 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
46 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
47 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
48 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
49 * SOFTWARE.
50 */
51
52 /*
53 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
54 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
55 *
56 * Permission to use, copy, modify, and distribute this software for any
57 * purpose with or without fee is hereby granted, provided that the above
58 * copyright notice and this permission notice appear in all copies.
59 *
60 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
61 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
62 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
63 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
64 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
65 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
66 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
67 */
68
69 #include "port_before.h"
70
71 #include "namespace.h"
72
73 #include <sys/param.h>
74 #include <sys/socket.h>
75 #include <sys/stat.h>
76 #include <sys/time.h>
77
78 #include <netinet/in.h>
79 #include <arpa/inet.h>
80 #include <arpa/nameser.h>
81
82 #include <ctype.h>
83 #include <stdio.h>
84 #include <stdlib.h>
85 #include <string.h>
86 #include <unistd.h>
87 #include <netdb.h>
88
89 #ifndef HAVE_MD5
90 # include "../dst/md5.h"
91 #else
92 # ifdef SOLARIS2
93 # include <sys/md5.h>
94 # elif _LIBC
95 # include <md5.h>
96 # endif
97 #endif
98 #ifndef _MD5_H_
99 # define _MD5_H_ 1 /*%< make sure we do not include rsaref md5.h file */
100 #endif
101
102 #include "un-namespace.h"
103
104 #include "port_after.h"
105
106 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
107 #include <resolv.h>
108
109 #include "res_private.h"
110
111 /*% Options. Should all be left alone. */
112 #define RESOLVSORT
113 #ifndef DEBUG
114 #define DEBUG
115 #endif
116
117 #ifdef SOLARIS2
118 #include <sys/systeminfo.h>
119 #endif
120
121 static void res_setoptions(res_state, const char *, const char *);
122
123 #ifdef RESOLVSORT
124 static const char sort_mask[] = "/&";
125 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
126 static u_int32_t net_mask(struct in_addr);
127 #endif
128
129 #if !defined(isascii) /*%< XXX - could be a function */
130 # define isascii(c) (!(c & 0200))
131 #endif
132
133 /*
134 * Resolver state default settings.
135 */
136
137 /*%
138 * Set up default settings. If the configuration file exist, the values
139 * there will have precedence. Otherwise, the server address is set to
140 * INADDR_ANY and the default domain name comes from the gethostname().
141 *
142 * An interim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
143 * rather than INADDR_ANY ("0.0.0.0") as the default name server address
144 * since it was noted that INADDR_ANY actually meant ``the first interface
145 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
146 * it had to be "up" in order for you to reach your own name server. It
147 * was later decided that since the recommended practice is to always
148 * install local static routes through 127.0.0.1 for all your network
149 * interfaces, that we could solve this problem without a code change.
150 *
151 * The configuration file should always be used, since it is the only way
152 * to specify a default domain. If you are running a server on your local
153 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
154 * in the configuration file.
155 *
156 * Return 0 if completes successfully, -1 on error
157 */
158 int
res_ninit(res_state statp)159 res_ninit(res_state statp) {
160 extern int __res_vinit(res_state, int);
161
162 return (__res_vinit(statp, 0));
163 }
164
165 /*% This function has to be reachable by res_data.c but not publicly. */
166 int
__res_vinit(res_state statp,int preinit)167 __res_vinit(res_state statp, int preinit) {
168 FILE *fp;
169 char *cp, **pp;
170 int n;
171 char buf[BUFSIZ];
172 int nserv = 0; /*%< number of nameserver records read from file */
173 int haveenv = 0;
174 int havesearch = 0;
175 #ifdef RESOLVSORT
176 int nsort = 0;
177 char *net;
178 #endif
179 int dots;
180 union res_sockaddr_union u[2];
181 int maxns = MAXNS;
182
183 RES_SET_H_ERRNO(statp, 0);
184 if (statp->_u._ext.ext != NULL)
185 res_ndestroy(statp);
186
187 if (!preinit) {
188 statp->retrans = RES_TIMEOUT;
189 statp->retry = RES_DFLRETRY;
190 statp->options = RES_DEFAULT;
191 }
192
193 statp->_rnd = malloc(16);
194 res_rndinit(statp);
195 statp->id = res_nrandomid(statp);
196
197 memset(u, 0, sizeof(u));
198 u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
199 u[nserv].sin.sin_family = AF_INET;
200 u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
201 #ifdef HAVE_SA_LEN
202 u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
203 #endif
204 nserv++;
205 #ifdef HAS_INET6_STRUCTS
206 u[nserv].sin6.sin6_addr = in6addr_any;
207 u[nserv].sin6.sin6_family = AF_INET6;
208 u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
209 #ifdef HAVE_SA_LEN
210 u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
211 #endif
212 nserv++;
213 #endif
214 statp->nscount = 0;
215 statp->ndots = 1;
216 statp->pfcode = 0;
217 statp->_vcsock = -1;
218 statp->_flags = 0;
219 statp->qhook = NULL;
220 statp->rhook = NULL;
221 statp->_u._ext.nscount = 0;
222 statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
223 if (statp->_u._ext.ext != NULL) {
224 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
225 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
226 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
227 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
228 statp->_u._ext.ext->reload_period = 2;
229 } else {
230 /*
231 * Historically res_init() rarely, if at all, failed.
232 * Examples and applications exist which do not check
233 * our return code. Furthermore several applications
234 * simply call us to get the systems domainname. So
235 * rather then immediately fail here we store the
236 * failure, which is returned later, in h_errno. And
237 * prevent the collection of 'nameserver' information
238 * by setting maxns to 0. Thus applications that fail
239 * to check our return code wont be able to make
240 * queries anyhow.
241 */
242 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
243 maxns = 0;
244 }
245 #ifdef RESOLVSORT
246 statp->nsort = 0;
247 #endif
248 res_setservers(statp, u, nserv);
249
250 #ifdef SOLARIS2
251 /*
252 * The old libresolv derived the defaultdomain from NIS/NIS+.
253 * We want to keep this behaviour
254 */
255 {
256 char buf[sizeof(statp->defdname)], *cp;
257 int ret;
258
259 if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 &&
260 (unsigned int)ret <= sizeof(buf)) {
261 if (buf[0] == '+')
262 buf[0] = '.';
263 cp = strchr(buf, '.');
264 cp = (cp == NULL) ? buf : (cp + 1);
265 strncpy(statp->defdname, cp,
266 sizeof(statp->defdname) - 1);
267 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
268 }
269 }
270 #endif /* SOLARIS2 */
271
272 /* Allow user to override the local domain definition */
273 if ((cp = secure_getenv("LOCALDOMAIN")) != NULL) {
274 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
275 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
276 haveenv++;
277
278 /*
279 * Set search list to be blank-separated strings
280 * from rest of env value. Permits users of LOCALDOMAIN
281 * to still have a search list, and anyone to set the
282 * one that they want to use as an individual (even more
283 * important now that the rfc1535 stuff restricts searches)
284 */
285 cp = statp->defdname;
286 pp = statp->dnsrch;
287 *pp++ = cp;
288 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
289 if (*cp == '\n') /*%< silly backwards compat */
290 break;
291 else if (*cp == ' ' || *cp == '\t') {
292 *cp = 0;
293 n = 1;
294 } else if (n) {
295 *pp++ = cp;
296 n = 0;
297 havesearch = 1;
298 }
299 }
300 /* null terminate last domain if there are excess */
301 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
302 cp++;
303 *cp = '\0';
304 *pp++ = NULL;
305 }
306
307 #define MATCH(line, name) \
308 (!strncmp(line, name, sizeof(name) - 1) && \
309 (line[sizeof(name) - 1] == ' ' || \
310 line[sizeof(name) - 1] == '\t'))
311
312 nserv = 0;
313 if ((fp = fopen(_PATH_RESCONF, "re")) != NULL) {
314 struct stat sb;
315 struct timespec now;
316
317 if (statp->_u._ext.ext != NULL) {
318 if (_fstat(fileno(fp), &sb) == 0) {
319 statp->_u._ext.ext->conf_mtim = sb.st_mtim;
320 if (clock_gettime(CLOCK_MONOTONIC_FAST, &now) == 0) {
321 statp->_u._ext.ext->conf_stat = now.tv_sec;
322 }
323 }
324 }
325
326 /* read the config file */
327 while (fgets(buf, sizeof(buf), fp) != NULL) {
328 /* skip comments */
329 if (*buf == ';' || *buf == '#')
330 continue;
331 /* read default domain name */
332 if (MATCH(buf, "domain")) {
333 if (haveenv) /*%< skip if have from environ */
334 continue;
335 cp = buf + sizeof("domain") - 1;
336 while (*cp == ' ' || *cp == '\t')
337 cp++;
338 if ((*cp == '\0') || (*cp == '\n'))
339 continue;
340 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
341 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
342 if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
343 *cp = '\0';
344 havesearch = 0;
345 continue;
346 }
347 /* set search list */
348 if (MATCH(buf, "search")) {
349 if (haveenv) /*%< skip if have from environ */
350 continue;
351 cp = buf + sizeof("search") - 1;
352 while (*cp == ' ' || *cp == '\t')
353 cp++;
354 if ((*cp == '\0') || (*cp == '\n'))
355 continue;
356 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
357 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
358 if ((cp = strchr(statp->defdname, '\n')) != NULL)
359 *cp = '\0';
360 /*
361 * Set search list to be blank-separated strings
362 * on rest of line.
363 */
364 cp = statp->defdname;
365 pp = statp->dnsrch;
366 *pp++ = cp;
367 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
368 if (*cp == ' ' || *cp == '\t') {
369 *cp = 0;
370 n = 1;
371 } else if (n) {
372 *pp++ = cp;
373 n = 0;
374 }
375 }
376 /* null terminate last domain if there are excess */
377 while (*cp != '\0' && *cp != ' ' && *cp != '\t')
378 cp++;
379 *cp = '\0';
380 *pp++ = NULL;
381 havesearch = 1;
382 continue;
383 }
384 /* read nameservers to query */
385 if (MATCH(buf, "nameserver") && nserv < maxns) {
386 struct addrinfo hints, *ai;
387 char sbuf[NI_MAXSERV];
388 const size_t minsiz =
389 sizeof(statp->_u._ext.ext->nsaddrs[0]);
390
391 cp = buf + sizeof("nameserver") - 1;
392 while (*cp == ' ' || *cp == '\t')
393 cp++;
394 cp[strcspn(cp, ";# \t\n")] = '\0';
395 if ((*cp != '\0') && (*cp != '\n')) {
396 memset(&hints, 0, sizeof(hints));
397 hints.ai_family = PF_UNSPEC;
398 hints.ai_socktype = SOCK_DGRAM; /*dummy*/
399 hints.ai_flags = AI_NUMERICHOST;
400 sprintf(sbuf, "%u", NAMESERVER_PORT);
401 if (getaddrinfo(cp, sbuf, &hints, &ai) == 0) {
402 if (ai->ai_addrlen <= minsiz) {
403 if (statp->_u._ext.ext != NULL) {
404 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
405 ai->ai_addr, ai->ai_addrlen);
406 }
407 if (ai->ai_addrlen <=
408 sizeof(statp->nsaddr_list[nserv])) {
409 memcpy(&statp->nsaddr_list[nserv],
410 ai->ai_addr, ai->ai_addrlen);
411 } else
412 statp->nsaddr_list[nserv].sin_family = 0;
413 nserv++;
414 }
415 freeaddrinfo(ai);
416 }
417 }
418 continue;
419 }
420 #ifdef RESOLVSORT
421 if (MATCH(buf, "sortlist")) {
422 struct in_addr a;
423 struct in6_addr a6;
424 int m, i;
425 u_char *u;
426 struct __res_state_ext *ext = statp->_u._ext.ext;
427
428 cp = buf + sizeof("sortlist") - 1;
429 while (nsort < MAXRESOLVSORT) {
430 while (*cp == ' ' || *cp == '\t')
431 cp++;
432 if (*cp == '\0' || *cp == '\n' || *cp == ';')
433 break;
434 net = cp;
435 while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
436 isascii(*cp) && !isspace((unsigned char)*cp))
437 cp++;
438 n = *cp;
439 *cp = 0;
440 if (inet_aton(net, &a)) {
441 statp->sort_list[nsort].addr = a;
442 if (ISSORTMASK(n)) {
443 *cp++ = n;
444 net = cp;
445 while (*cp && *cp != ';' &&
446 isascii(*cp) &&
447 !isspace((unsigned char)*cp))
448 cp++;
449 n = *cp;
450 *cp = 0;
451 if (inet_aton(net, &a)) {
452 statp->sort_list[nsort].mask = a.s_addr;
453 } else {
454 statp->sort_list[nsort].mask =
455 net_mask(statp->sort_list[nsort].addr);
456 }
457 } else {
458 statp->sort_list[nsort].mask =
459 net_mask(statp->sort_list[nsort].addr);
460 }
461 ext->sort_list[nsort].af = AF_INET;
462 ext->sort_list[nsort].addr.ina =
463 statp->sort_list[nsort].addr;
464 ext->sort_list[nsort].mask.ina.s_addr =
465 statp->sort_list[nsort].mask;
466 nsort++;
467 }
468 else if (inet_pton(AF_INET6, net, &a6) == 1) {
469
470 ext->sort_list[nsort].af = AF_INET6;
471 ext->sort_list[nsort].addr.in6a = a6;
472 u = (u_char *)&ext->sort_list[nsort].mask.in6a;
473 *cp++ = n;
474 net = cp;
475 while (*cp && *cp != ';' &&
476 isascii(*cp) && !isspace(*cp))
477 cp++;
478 m = n;
479 n = *cp;
480 *cp = 0;
481 switch (m) {
482 case '/':
483 m = atoi(net);
484 break;
485 case '&':
486 if (inet_pton(AF_INET6, net, u) == 1) {
487 m = -1;
488 break;
489 }
490 /*FALLTHROUGH*/
491 default:
492 m = sizeof(struct in6_addr) * CHAR_BIT;
493 break;
494 }
495 if (m >= 0) {
496 for (i = 0; i < sizeof(struct in6_addr); i++) {
497 if (m <= 0) {
498 *u = 0;
499 } else {
500 m -= CHAR_BIT;
501 *u = (u_char)~0;
502 if (m < 0)
503 *u <<= -m;
504 }
505 u++;
506 }
507 }
508 statp->sort_list[nsort].addr.s_addr =
509 (u_int32_t)0xffffffff;
510 statp->sort_list[nsort].mask =
511 (u_int32_t)0xffffffff;
512 nsort++;
513 }
514 *cp = n;
515 }
516 continue;
517 }
518 #endif
519 if (MATCH(buf, "options")) {
520 res_setoptions(statp, buf + sizeof("options") - 1, "conf");
521 continue;
522 }
523 }
524 if (nserv > 0)
525 statp->nscount = nserv;
526 #ifdef RESOLVSORT
527 statp->nsort = nsort;
528 #endif
529 (void) fclose(fp);
530 }
531 /*
532 * Last chance to get a nameserver. This should not normally
533 * be necessary
534 */
535 #ifdef NO_RESOLV_CONF
536 if(nserv == 0)
537 nserv = get_nameservers(statp);
538 #endif
539
540 if (statp->defdname[0] == 0 &&
541 gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
542 (cp = strchr(buf, '.')) != NULL)
543 strcpy(statp->defdname, cp + 1);
544
545 /* find components of local domain that might be searched */
546 if (havesearch == 0) {
547 pp = statp->dnsrch;
548 *pp++ = statp->defdname;
549 *pp = NULL;
550
551 dots = 0;
552 for (cp = statp->defdname; *cp; cp++)
553 dots += (*cp == '.');
554
555 cp = statp->defdname;
556 while (pp < statp->dnsrch + MAXDFLSRCH) {
557 if (dots < LOCALDOMAINPARTS)
558 break;
559 cp = strchr(cp, '.') + 1; /*%< we know there is one */
560 *pp++ = cp;
561 dots--;
562 }
563 *pp = NULL;
564 #ifdef DEBUG
565 if (statp->options & RES_DEBUG) {
566 printf(";; res_init()... default dnsrch list:\n");
567 for (pp = statp->dnsrch; *pp; pp++)
568 printf(";;\t%s\n", *pp);
569 printf(";;\t..END..\n");
570 }
571 #endif
572 }
573
574 if (issetugid())
575 statp->options |= RES_NOALIASES;
576 else if ((cp = getenv("RES_OPTIONS")) != NULL)
577 res_setoptions(statp, cp, "env");
578 statp->options |= RES_INIT;
579 return (statp->res_h_errno);
580 }
581
582 static void
res_setoptions(res_state statp,const char * options,const char * source)583 res_setoptions(res_state statp, const char *options, const char *source)
584 {
585 const char *cp = options;
586 int i;
587 struct __res_state_ext *ext = statp->_u._ext.ext;
588
589 #ifdef DEBUG
590 if (statp->options & RES_DEBUG)
591 printf(";; res_setoptions(\"%s\", \"%s\")...\n",
592 options, source);
593 #endif
594 while (*cp) {
595 /* skip leading and inner runs of spaces */
596 while (*cp == ' ' || *cp == '\t')
597 cp++;
598 /* search for and process individual options */
599 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
600 i = atoi(cp + sizeof("ndots:") - 1);
601 if (i <= RES_MAXNDOTS)
602 statp->ndots = i;
603 else
604 statp->ndots = RES_MAXNDOTS;
605 #ifdef DEBUG
606 if (statp->options & RES_DEBUG)
607 printf(";;\tndots=%d\n", statp->ndots);
608 #endif
609 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
610 i = atoi(cp + sizeof("timeout:") - 1);
611 if (i <= RES_MAXRETRANS)
612 statp->retrans = i;
613 else
614 statp->retrans = RES_MAXRETRANS;
615 #ifdef DEBUG
616 if (statp->options & RES_DEBUG)
617 printf(";;\ttimeout=%d\n", statp->retrans);
618 #endif
619 #ifdef SOLARIS2
620 } else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) {
621 /*
622 * For backward compatibility, 'retrans' is
623 * supported as an alias for 'timeout', though
624 * without an imposed maximum.
625 */
626 statp->retrans = atoi(cp + sizeof("retrans:") - 1);
627 } else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){
628 /*
629 * For backward compatibility, 'retry' is
630 * supported as an alias for 'attempts', though
631 * without an imposed maximum.
632 */
633 statp->retry = atoi(cp + sizeof("retry:") - 1);
634 #endif /* SOLARIS2 */
635 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
636 i = atoi(cp + sizeof("attempts:") - 1);
637 if (i <= RES_MAXRETRY)
638 statp->retry = i;
639 else
640 statp->retry = RES_MAXRETRY;
641 #ifdef DEBUG
642 if (statp->options & RES_DEBUG)
643 printf(";;\tattempts=%d\n", statp->retry);
644 #endif
645 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
646 #ifdef DEBUG
647 if (!(statp->options & RES_DEBUG)) {
648 printf(";; res_setoptions(\"%s\", \"%s\")..\n",
649 options, source);
650 statp->options |= RES_DEBUG;
651 }
652 printf(";;\tdebug\n");
653 #endif
654 } else if (!strncmp(cp, "no_tld_query",
655 sizeof("no_tld_query") - 1) ||
656 !strncmp(cp, "no-tld-query",
657 sizeof("no-tld-query") - 1)) {
658 statp->options |= RES_NOTLDQUERY;
659 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
660 statp->options |= RES_USE_INET6;
661 } else if (!strncmp(cp, "insecure1", sizeof("insecure1") - 1)) {
662 statp->options |= RES_INSECURE1;
663 } else if (!strncmp(cp, "insecure2", sizeof("insecure2") - 1)) {
664 statp->options |= RES_INSECURE2;
665 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
666 statp->options |= RES_ROTATE;
667 } else if (!strncmp(cp, "usevc", sizeof("usevc") - 1)) {
668 statp->options |= RES_USEVC;
669 } else if (!strncmp(cp, "no-check-names",
670 sizeof("no-check-names") - 1)) {
671 statp->options |= RES_NOCHECKNAME;
672 } else if (!strncmp(cp, "reload-period:",
673 sizeof("reload-period:") - 1)) {
674 if (ext != NULL) {
675 ext->reload_period = (u_short)
676 atoi(cp + sizeof("reload-period:") - 1);
677 }
678 }
679 #ifdef RES_USE_EDNS0
680 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
681 statp->options |= RES_USE_EDNS0;
682 }
683 #endif
684 #ifndef _LIBC
685 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
686 statp->options |= RES_USE_DNAME;
687 }
688 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
689 if (ext == NULL)
690 goto skip;
691 cp += sizeof("nibble:") - 1;
692 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
693 strncpy(ext->nsuffix, cp, i);
694 ext->nsuffix[i] = '\0';
695 }
696 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
697 if (ext == NULL)
698 goto skip;
699 cp += sizeof("nibble2:") - 1;
700 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
701 strncpy(ext->nsuffix2, cp, i);
702 ext->nsuffix2[i] = '\0';
703 }
704 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
705 cp += sizeof("v6revmode:") - 1;
706 /* "nibble" and "bitstring" used to be valid */
707 if (!strncmp(cp, "single", sizeof("single") - 1)) {
708 statp->options |= RES_NO_NIBBLE2;
709 } else if (!strncmp(cp, "both", sizeof("both") - 1)) {
710 statp->options &=
711 ~RES_NO_NIBBLE2;
712 }
713 }
714 #endif
715 else {
716 /* XXX - print a warning here? */
717 }
718 #ifndef _LIBC
719 skip:
720 #endif
721 /* skip to next run of spaces */
722 while (*cp && *cp != ' ' && *cp != '\t')
723 cp++;
724 }
725 }
726
727 #ifdef RESOLVSORT
728 /* XXX - should really support CIDR which means explicit masks always. */
729 static u_int32_t
net_mask(struct in_addr in)730 net_mask(struct in_addr in) /*!< XXX - should really use system's version of this */
731 {
732 u_int32_t i = ntohl(in.s_addr);
733
734 if (IN_CLASSA(i))
735 return (htonl(IN_CLASSA_NET));
736 else if (IN_CLASSB(i))
737 return (htonl(IN_CLASSB_NET));
738 return (htonl(IN_CLASSC_NET));
739 }
740 #endif
741
742 static u_char srnd[16];
743
744 void
res_rndinit(res_state statp)745 res_rndinit(res_state statp)
746 {
747 struct timeval now;
748 u_int32_t u32;
749 u_int16_t u16;
750 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd;
751
752 gettimeofday(&now, NULL);
753 u32 = now.tv_sec;
754 memcpy(rnd, &u32, 4);
755 u32 = now.tv_usec;
756 memcpy(rnd + 4, &u32, 4);
757 u32 += now.tv_sec;
758 memcpy(rnd + 8, &u32, 4);
759 u16 = getpid();
760 memcpy(rnd + 12, &u16, 2);
761 }
762
763 u_int
res_nrandomid(res_state statp)764 res_nrandomid(res_state statp) {
765 struct timeval now;
766 u_int16_t u16;
767 MD5_CTX ctx;
768 u_char *rnd = statp->_rnd == NULL ? srnd : statp->_rnd;
769
770 gettimeofday(&now, NULL);
771 u16 = (u_int16_t) (now.tv_sec ^ now.tv_usec);
772 memcpy(rnd + 14, &u16, 2);
773 #ifndef HAVE_MD5
774 MD5_Init(&ctx);
775 MD5_Update(&ctx, rnd, 16);
776 MD5_Final(rnd, &ctx);
777 #else
778 MD5Init(&ctx);
779 MD5Update(&ctx, rnd, 16);
780 MD5Final(rnd, &ctx);
781 #endif
782 memcpy(&u16, rnd + 14, 2);
783 return ((u_int) u16);
784 }
785
786 /*%
787 * This routine is for closing the socket if a virtual circuit is used and
788 * the program wants to close it. This provides support for endhostent()
789 * which expects to close the socket.
790 *
791 * This routine is not expected to be user visible.
792 */
793 void
res_nclose(res_state statp)794 res_nclose(res_state statp) {
795 int ns;
796
797 if (statp->_vcsock >= 0) {
798 (void) _close(statp->_vcsock);
799 statp->_vcsock = -1;
800 statp->_flags &= ~(RES_F_VC | RES_F_CONN);
801 }
802 for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
803 if (statp->_u._ext.nssocks[ns] != -1) {
804 (void) _close(statp->_u._ext.nssocks[ns]);
805 statp->_u._ext.nssocks[ns] = -1;
806 }
807 }
808 }
809
810 void
res_ndestroy(res_state statp)811 res_ndestroy(res_state statp) {
812 res_nclose(statp);
813 if (statp->_u._ext.ext != NULL) {
814 free(statp->_u._ext.ext);
815 statp->_u._ext.ext = NULL;
816 }
817 if (statp->_rnd != NULL) {
818 free(statp->_rnd);
819 statp->_rnd = NULL;
820 }
821 statp->options &= ~RES_INIT;
822 }
823
824 #ifndef _LIBC
825 const char *
res_get_nibblesuffix(res_state statp)826 res_get_nibblesuffix(res_state statp) {
827 if (statp->_u._ext.ext)
828 return (statp->_u._ext.ext->nsuffix);
829 return ("ip6.arpa");
830 }
831
832 const char *
res_get_nibblesuffix2(res_state statp)833 res_get_nibblesuffix2(res_state statp) {
834 if (statp->_u._ext.ext)
835 return (statp->_u._ext.ext->nsuffix2);
836 return ("ip6.int");
837 }
838 #endif
839
840 void
res_setservers(res_state statp,const union res_sockaddr_union * set,int cnt)841 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
842 int i, nserv;
843 size_t size;
844
845 /* close open servers */
846 res_nclose(statp);
847
848 /* cause rtt times to be forgotten */
849 statp->_u._ext.nscount = 0;
850
851 nserv = 0;
852 for (i = 0; i < cnt && nserv < MAXNS; i++) {
853 switch (set->sin.sin_family) {
854 case AF_INET:
855 size = sizeof(set->sin);
856 if (statp->_u._ext.ext)
857 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
858 &set->sin, size);
859 if (size <= sizeof(statp->nsaddr_list[nserv]))
860 memcpy(&statp->nsaddr_list[nserv],
861 &set->sin, size);
862 else
863 statp->nsaddr_list[nserv].sin_family = 0;
864 nserv++;
865 break;
866
867 #ifdef HAS_INET6_STRUCTS
868 case AF_INET6:
869 size = sizeof(set->sin6);
870 if (statp->_u._ext.ext)
871 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
872 &set->sin6, size);
873 if (size <= sizeof(statp->nsaddr_list[nserv]))
874 memcpy(&statp->nsaddr_list[nserv],
875 &set->sin6, size);
876 else
877 statp->nsaddr_list[nserv].sin_family = 0;
878 nserv++;
879 break;
880 #endif
881
882 default:
883 break;
884 }
885 set++;
886 }
887 statp->nscount = nserv;
888
889 }
890
891 int
res_getservers(res_state statp,union res_sockaddr_union * set,int cnt)892 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
893 int i;
894 size_t size;
895 u_int16_t family;
896
897 for (i = 0; i < statp->nscount && i < cnt; i++) {
898 if (statp->_u._ext.ext)
899 family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
900 else
901 family = statp->nsaddr_list[i].sin_family;
902
903 switch (family) {
904 case AF_INET:
905 size = sizeof(set->sin);
906 if (statp->_u._ext.ext)
907 memcpy(&set->sin,
908 &statp->_u._ext.ext->nsaddrs[i],
909 size);
910 else
911 memcpy(&set->sin, &statp->nsaddr_list[i],
912 size);
913 break;
914
915 #ifdef HAS_INET6_STRUCTS
916 case AF_INET6:
917 size = sizeof(set->sin6);
918 if (statp->_u._ext.ext)
919 memcpy(&set->sin6,
920 &statp->_u._ext.ext->nsaddrs[i],
921 size);
922 else
923 memcpy(&set->sin6, &statp->nsaddr_list[i],
924 size);
925 break;
926 #endif
927
928 default:
929 set->sin.sin_family = 0;
930 break;
931 }
932 set++;
933 }
934 return (statp->nscount);
935 }
936
937 /*! \file */
938