1 /* $NetBSD: res_init.c,v 1.8 2006/03/19 03:10:08 christos Exp $ */
2
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. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by the University of
18 * California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 /*
37 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
38 *
39 * Permission to use, copy, modify, and distribute this software for any
40 * purpose with or without fee is hereby granted, provided that the above
41 * copyright notice and this permission notice appear in all copies, and that
42 * the name of Digital Equipment Corporation not be used in advertising or
43 * publicity pertaining to distribution of the document or software without
44 * specific, written prior permission.
45 *
46 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
47 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
48 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
49 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
50 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
51 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
52 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
53 * SOFTWARE.
54 */
55
56 /*
57 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
58 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
59 *
60 * Permission to use, copy, modify, and distribute this software for any
61 * purpose with or without fee is hereby granted, provided that the above
62 * copyright notice and this permission notice appear in all copies.
63 *
64 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
65 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
66 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
67 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
68 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
69 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
70 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
71 */
72
73 #include <sys/cdefs.h>
74 #if defined(LIBC_SCCS) && !defined(lint)
75 #ifdef notdef
76 static const char sccsid[] = "@(#)res_init.c 8.1 (Berkeley) 6/7/93";
77 static const char rcsid[] = "Id: res_init.c,v 1.9.2.5.4.2 2004/03/16 12:34:18 marka Exp";
78 #else
79 __RCSID("$NetBSD: res_init.c,v 1.8 2006/03/19 03:10:08 christos Exp $");
80 #endif
81 #endif /* LIBC_SCCS and not lint */
82
83
84
85 #include <sys/types.h>
86 #include <sys/param.h>
87 #include <sys/socket.h>
88 #include <sys/time.h>
89
90 #include <netinet/in.h>
91 #include <arpa/inet.h>
92 #include <arpa/nameser.h>
93
94 #include <ctype.h>
95 #include <stdio.h>
96 #include <stdlib.h>
97 #include <string.h>
98 #include <unistd.h>
99 #include <netdb.h>
100
101 #ifdef ANDROID_CHANGES
102 #include <errno.h>
103 #include <fcntl.h>
104 #include <sys/system_properties.h>
105 #endif /* ANDROID_CHANGES */
106
107 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
108 #ifdef ANDROID_CHANGES
109 #include "resolv_netid.h"
110 #include "resolv_private.h"
111 #else
112 #include <resolv.h>
113 #endif
114
115 #include "res_private.h"
116
117 /* Options. Should all be left alone. */
118 #ifndef DEBUG
119 #define DEBUG
120 #endif
121
122 static void res_setoptions __P((res_state, const char *, const char *));
123
124 #ifdef RESOLVSORT
125 static const char sort_mask[] = "/&";
126 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
127 static uint32_t net_mask(struct in_addr);
128 #endif
129
130 #if !defined(isascii) /* XXX - could be a function */
131 # define isascii(c) (!(c & 0200))
132 #endif
133
134 /*
135 * Resolver state default settings.
136 */
137
138 /*
139 * Set up default settings. If the configuration file exist, the values
140 * there will have precedence. Otherwise, the server address is set to
141 * INADDR_ANY and the default domain name comes from the gethostname().
142 *
143 * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
144 * rather than INADDR_ANY ("0.0.0.0") as the default name server address
145 * since it was noted that INADDR_ANY actually meant ``the first interface
146 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
147 * it had to be "up" in order for you to reach your own name server. It
148 * was later decided that since the recommended practice is to always
149 * install local static routes through 127.0.0.1 for all your network
150 * interfaces, that we could solve this problem without a code change.
151 *
152 * The configuration file should always be used, since it is the only way
153 * to specify a default domain. If you are running a server on your local
154 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
155 * in the configuration file.
156 *
157 * Return 0 if completes successfully, -1 on error
158 */
159 int
res_ninit(res_state statp)160 res_ninit(res_state statp) {
161 extern int __res_vinit(res_state, int);
162
163 return (__res_vinit(statp, 0));
164 }
165
166 /* This function has to be reachable by res_data.c but not publicly. */
167 int
__res_vinit(res_state statp,int preinit)168 __res_vinit(res_state statp, int preinit) {
169 #if !defined(__ANDROID__)
170 register FILE *fp;
171 #endif
172 register char *cp, **pp;
173 #if !defined(__ANDROID__)
174 register int n;
175 #endif
176 char buf[BUFSIZ];
177 int nserv = 0; /* number of nameserver records read from file */
178 #if !defined(__ANDROID__)
179 int haveenv = 0;
180 #endif
181 int havesearch = 0;
182 #ifdef RESOLVSORT
183 int nsort = 0;
184 #endif
185 #if !defined(__ANDROID__)
186 char *net;
187 #endif
188 int dots;
189 union res_sockaddr_union u[2];
190
191 if ((statp->options & RES_INIT) != 0U)
192 res_ndestroy(statp);
193
194 if (!preinit) {
195 statp->netid = NETID_UNSET;
196 statp->retrans = RES_TIMEOUT;
197 statp->retry = RES_DFLRETRY;
198 statp->options = RES_DEFAULT;
199 statp->id = res_randomid();
200 statp->_mark = MARK_UNSET;
201 }
202
203 memset(u, 0, sizeof(u));
204 #ifdef USELOOPBACK
205 u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
206 #else
207 u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
208 #endif
209 u[nserv].sin.sin_family = AF_INET;
210 u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
211 #ifdef HAVE_SA_LEN
212 u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
213 #endif
214 nserv++;
215 #ifdef HAS_INET6_STRUCTS
216 #ifdef USELOOPBACK
217 u[nserv].sin6.sin6_addr = in6addr_loopback;
218 #else
219 u[nserv].sin6.sin6_addr = in6addr_any;
220 #endif
221 u[nserv].sin6.sin6_family = AF_INET6;
222 u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
223 #ifdef HAVE_SA_LEN
224 u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
225 #endif
226 nserv++;
227 #endif
228 statp->nscount = 0;
229 statp->ndots = 1;
230 statp->pfcode = 0;
231 statp->_vcsock = -1;
232 statp->_flags = 0;
233 statp->qhook = NULL;
234 statp->rhook = NULL;
235 statp->_u._ext.nscount = 0;
236 statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
237 if (statp->_u._ext.ext != NULL) {
238 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
239 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
240 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
241 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
242 }
243 statp->nsort = 0;
244 res_setservers(statp, u, nserv);
245
246 #if !defined(__ANDROID__) /* IGNORE THE ENVIRONMENT */
247 /* Allow user to override the local domain definition */
248 if ((cp = getenv("LOCALDOMAIN")) != NULL) {
249 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
250 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
251 haveenv++;
252
253 /*
254 * Set search list to be blank-separated strings
255 * from rest of env value. Permits users of LOCALDOMAIN
256 * to still have a search list, and anyone to set the
257 * one that they want to use as an individual (even more
258 * important now that the rfc1535 stuff restricts searches)
259 */
260 cp = statp->defdname;
261 pp = statp->dnsrch;
262 *pp++ = cp;
263 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
264 if (*cp == '\n') /* silly backwards compat */
265 break;
266 else if (*cp == ' ' || *cp == '\t') {
267 *cp = 0;
268 n = 1;
269 } else if (n) {
270 *pp++ = cp;
271 n = 0;
272 havesearch = 1;
273 }
274 }
275 /* null terminate last domain if there are excess */
276 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
277 cp++;
278 *cp = '\0';
279 *pp++ = 0;
280 }
281 if (nserv > 0)
282 statp->nscount = nserv;
283 #endif
284
285 #ifndef ANDROID_CHANGES /* !ANDROID_CHANGES - IGNORE resolv.conf in Android */
286 #define MATCH(line, name) \
287 (!strncmp(line, name, sizeof(name) - 1) && \
288 (line[sizeof(name) - 1] == ' ' || \
289 line[sizeof(name) - 1] == '\t'))
290
291 nserv = 0;
292 if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
293 /* read the config file */
294 while (fgets(buf, sizeof(buf), fp) != NULL) {
295 /* skip comments */
296 if (*buf == ';' || *buf == '#')
297 continue;
298 /* read default domain name */
299 if (MATCH(buf, "domain")) {
300 if (haveenv) /* skip if have from environ */
301 continue;
302 cp = buf + sizeof("domain") - 1;
303 while (*cp == ' ' || *cp == '\t')
304 cp++;
305 if ((*cp == '\0') || (*cp == '\n'))
306 continue;
307 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
308 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
309 if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
310 *cp = '\0';
311 havesearch = 0;
312 continue;
313 }
314 /* set search list */
315 if (MATCH(buf, "search")) {
316 if (haveenv) /* skip if have from environ */
317 continue;
318 cp = buf + sizeof("search") - 1;
319 while (*cp == ' ' || *cp == '\t')
320 cp++;
321 if ((*cp == '\0') || (*cp == '\n'))
322 continue;
323 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
324 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
325 if ((cp = strchr(statp->defdname, '\n')) != NULL)
326 *cp = '\0';
327 /*
328 * Set search list to be blank-separated strings
329 * on rest of line.
330 */
331 cp = statp->defdname;
332 pp = statp->dnsrch;
333 *pp++ = cp;
334 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
335 if (*cp == ' ' || *cp == '\t') {
336 *cp = 0;
337 n = 1;
338 } else if (n) {
339 *pp++ = cp;
340 n = 0;
341 }
342 }
343 /* null terminate last domain if there are excess */
344 while (*cp != '\0' && *cp != ' ' && *cp != '\t')
345 cp++;
346 *cp = '\0';
347 *pp++ = 0;
348 havesearch = 1;
349 continue;
350 }
351 /* read nameservers to query */
352 if (MATCH(buf, "nameserver") && nserv < MAXNS) {
353 struct addrinfo hints, *ai;
354 char sbuf[NI_MAXSERV];
355 const size_t minsiz =
356 sizeof(statp->_u._ext.ext->nsaddrs[0]);
357
358 cp = buf + sizeof("nameserver") - 1;
359 while (*cp == ' ' || *cp == '\t')
360 cp++;
361 cp[strcspn(cp, ";# \t\n")] = '\0';
362 if ((*cp != '\0') && (*cp != '\n')) {
363 memset(&hints, 0, sizeof(hints));
364 hints.ai_family = PF_UNSPEC;
365 hints.ai_socktype = SOCK_DGRAM; /*dummy*/
366 hints.ai_flags = AI_NUMERICHOST;
367 sprintf(sbuf, "%u", NAMESERVER_PORT);
368 if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
369 ai->ai_addrlen <= minsiz) {
370 if (statp->_u._ext.ext != NULL) {
371 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
372 ai->ai_addr, ai->ai_addrlen);
373 }
374 if (ai->ai_addrlen <=
375 sizeof(statp->nsaddr_list[nserv])) {
376 memcpy(&statp->nsaddr_list[nserv],
377 ai->ai_addr, ai->ai_addrlen);
378 } else
379 statp->nsaddr_list[nserv].sin_family = 0;
380 freeaddrinfo(ai);
381 nserv++;
382 }
383 }
384 continue;
385 }
386 if (MATCH(buf, "sortlist")) {
387 struct in_addr a;
388
389 cp = buf + sizeof("sortlist") - 1;
390 while (nsort < MAXRESOLVSORT) {
391 while (*cp == ' ' || *cp == '\t')
392 cp++;
393 if (*cp == '\0' || *cp == '\n' || *cp == ';')
394 break;
395 net = cp;
396 while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
397 isascii(*cp) && !isspace((unsigned char)*cp))
398 cp++;
399 n = *cp;
400 *cp = 0;
401 if (inet_aton(net, &a)) {
402 statp->sort_list[nsort].addr = a;
403 if (ISSORTMASK(n)) {
404 *cp++ = n;
405 net = cp;
406 while (*cp && *cp != ';' &&
407 isascii(*cp) &&
408 !isspace((unsigned char)*cp))
409 cp++;
410 n = *cp;
411 *cp = 0;
412 if (inet_aton(net, &a)) {
413 statp->sort_list[nsort].mask = a.s_addr;
414 } else {
415 statp->sort_list[nsort].mask =
416 net_mask(statp->sort_list[nsort].addr);
417 }
418 } else {
419 statp->sort_list[nsort].mask =
420 net_mask(statp->sort_list[nsort].addr);
421 }
422 nsort++;
423 }
424 *cp = n;
425 }
426 continue;
427 }
428 if (MATCH(buf, "options")) {
429 res_setoptions(statp, buf + sizeof("options") - 1, "conf");
430 continue;
431 }
432 }
433 if (nserv > 0)
434 statp->nscount = nserv;
435 statp->nsort = nsort;
436 (void) fclose(fp);
437 }
438 #endif /* !ANDROID_CHANGES */
439 /*
440 * Last chance to get a nameserver. This should not normally
441 * be necessary
442 */
443 #ifdef NO_RESOLV_CONF
444 if(nserv == 0)
445 nserv = get_nameservers(statp);
446 #endif
447
448 if (statp->defdname[0] == 0 &&
449 gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
450 (cp = strchr(buf, '.')) != NULL)
451 strcpy(statp->defdname, cp + 1);
452
453 /* find components of local domain that might be searched */
454 if (havesearch == 0) {
455 pp = statp->dnsrch;
456 *pp++ = statp->defdname;
457 *pp = NULL;
458
459 dots = 0;
460 for (cp = statp->defdname; *cp; cp++)
461 dots += (*cp == '.');
462
463 cp = statp->defdname;
464 while (pp < statp->dnsrch + MAXDFLSRCH) {
465 if (dots < LOCALDOMAINPARTS)
466 break;
467 cp = strchr(cp, '.') + 1; /* we know there is one */
468 *pp++ = cp;
469 dots--;
470 }
471 *pp = NULL;
472 #ifdef DEBUG
473 if (statp->options & RES_DEBUG) {
474 printf(";; res_init()... default dnsrch list:\n");
475 for (pp = statp->dnsrch; *pp; pp++)
476 printf(";;\t%s\n", *pp);
477 printf(";;\t..END..\n");
478 }
479 #endif
480 }
481
482 if ((cp = getenv("RES_OPTIONS")) != NULL)
483 res_setoptions(statp, cp, "env");
484 if (nserv > 0) {
485 statp->nscount = nserv;
486 statp->options |= RES_INIT;
487 }
488 return (0);
489 }
490
491 static void
res_setoptions(res_state statp,const char * options,const char * source)492 res_setoptions(res_state statp, const char *options, const char *source)
493 {
494 const char *cp = options;
495 int i;
496 struct __res_state_ext *ext = statp->_u._ext.ext;
497
498 #ifdef DEBUG
499 if (statp->options & RES_DEBUG)
500 printf(";; res_setoptions(\"%s\", \"%s\")...\n",
501 options, source);
502 #endif
503 while (*cp) {
504 /* skip leading and inner runs of spaces */
505 while (*cp == ' ' || *cp == '\t')
506 cp++;
507 /* search for and process individual options */
508 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
509 i = atoi(cp + sizeof("ndots:") - 1);
510 if (i <= RES_MAXNDOTS)
511 statp->ndots = i;
512 else
513 statp->ndots = RES_MAXNDOTS;
514 #ifdef DEBUG
515 if (statp->options & RES_DEBUG)
516 printf(";;\tndots=%d\n", statp->ndots);
517 #endif
518 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
519 i = atoi(cp + sizeof("timeout:") - 1);
520 if (i <= RES_MAXRETRANS)
521 statp->retrans = i;
522 else
523 statp->retrans = RES_MAXRETRANS;
524 #ifdef DEBUG
525 if (statp->options & RES_DEBUG)
526 printf(";;\ttimeout=%d\n", statp->retrans);
527 #endif
528 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
529 i = atoi(cp + sizeof("attempts:") - 1);
530 if (i <= RES_MAXRETRY)
531 statp->retry = i;
532 else
533 statp->retry = RES_MAXRETRY;
534 #ifdef DEBUG
535 if (statp->options & RES_DEBUG)
536 printf(";;\tattempts=%d\n", statp->retry);
537 #endif
538 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
539 #ifdef DEBUG
540 if (!(statp->options & RES_DEBUG)) {
541 printf(";; res_setoptions(\"%s\", \"%s\")..\n",
542 options, source);
543 statp->options |= RES_DEBUG;
544 }
545 printf(";;\tdebug\n");
546 #endif
547 } else if (!strncmp(cp, "no_tld_query",
548 sizeof("no_tld_query") - 1) ||
549 !strncmp(cp, "no-tld-query",
550 sizeof("no-tld-query") - 1)) {
551 statp->options |= RES_NOTLDQUERY;
552 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
553 statp->options |= RES_USE_INET6;
554 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
555 statp->options |= RES_ROTATE;
556 } else if (!strncmp(cp, "no-check-names",
557 sizeof("no-check-names") - 1)) {
558 statp->options |= RES_NOCHECKNAME;
559 }
560 #ifdef RES_USE_EDNS0
561 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
562 statp->options |= RES_USE_EDNS0;
563 }
564 #endif
565 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
566 statp->options |= RES_USE_DNAME;
567 }
568 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
569 if (ext == NULL)
570 goto skip;
571 cp += sizeof("nibble:") - 1;
572 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
573 strncpy(ext->nsuffix, cp, (size_t)i);
574 ext->nsuffix[i] = '\0';
575 }
576 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
577 if (ext == NULL)
578 goto skip;
579 cp += sizeof("nibble2:") - 1;
580 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
581 strncpy(ext->nsuffix2, cp, (size_t)i);
582 ext->nsuffix2[i] = '\0';
583 }
584 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
585 cp += sizeof("v6revmode:") - 1;
586 /* "nibble" and "bitstring" used to be valid */
587 if (!strncmp(cp, "single", sizeof("single") - 1)) {
588 statp->options |= RES_NO_NIBBLE2;
589 } else if (!strncmp(cp, "both", sizeof("both") - 1)) {
590 statp->options &=
591 ~RES_NO_NIBBLE2;
592 }
593 }
594 else {
595 /* XXX - print a warning here? */
596 }
597 skip:
598 /* skip to next run of spaces */
599 while (*cp && *cp != ' ' && *cp != '\t')
600 cp++;
601 }
602 }
603
604 #ifdef RESOLVSORT
605 /* XXX - should really support CIDR which means explicit masks always. */
606 static uint32_t
net_mask(struct in_addr in)607 net_mask(struct in_addr in) /*!< XXX - should really use system's version of this */
608 {
609 register uint32_t i = ntohl(in.s_addr);
610
611 if (IN_CLASSA(i))
612 return (htonl(IN_CLASSA_NET));
613 else if (IN_CLASSB(i))
614 return (htonl(IN_CLASSB_NET));
615 return (htonl(IN_CLASSC_NET));
616 }
617 #endif
618
619 #ifdef ANDROID_CHANGES
620 static int
real_randomid(u_int * random_value)621 real_randomid(u_int *random_value) {
622 /* open the nonblocking random device, returning -1 on failure */
623 int random_device = open("/dev/urandom", O_RDONLY | O_CLOEXEC);
624 if (random_device < 0) {
625 return -1;
626 }
627
628 /* read from the random device, returning -1 on failure (or too many retries)*/
629 for (u_int retry = 5; retry > 0; retry--) {
630 int retval = read(random_device, random_value, sizeof(u_int));
631 if (retval == sizeof(u_int)) {
632 *random_value &= 0xffff;
633 close(random_device);
634 return 0;
635 } else if ((retval < 0) && (errno != EINTR)) {
636 break;
637 }
638 }
639
640 close(random_device);
641 return -1;
642 }
643 #endif /* ANDROID_CHANGES */
644
645 u_int
res_randomid(void)646 res_randomid(void) {
647 #ifdef ANDROID_CHANGES
648 int status = 0;
649 u_int output = 0;
650 status = real_randomid(&output);
651 if (status != -1) {
652 return output;
653 }
654 #endif /* ANDROID_CHANGES */
655 struct timeval now;
656 gettimeofday(&now, NULL);
657 return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));
658 }
659
660 /*%
661 * This routine is for closing the socket if a virtual circuit is used and
662 * the program wants to close it. This provides support for endhostent()
663 * which expects to close the socket.
664 *
665 * This routine is not expected to be user visible.
666 */
667 void
res_nclose(res_state statp)668 res_nclose(res_state statp)
669 {
670 int ns;
671
672 if (statp->_vcsock >= 0) {
673 (void) close(statp->_vcsock);
674 statp->_vcsock = -1;
675 statp->_flags &= ~(RES_F_VC | RES_F_CONN);
676 }
677 for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
678 if (statp->_u._ext.nssocks[ns] != -1) {
679 (void) close(statp->_u._ext.nssocks[ns]);
680 statp->_u._ext.nssocks[ns] = -1;
681 }
682 }
683 }
684
685 void
res_ndestroy(res_state statp)686 res_ndestroy(res_state statp)
687 {
688 res_nclose(statp);
689 if (statp->_u._ext.ext != NULL)
690 free(statp->_u._ext.ext);
691 statp->options &= ~RES_INIT;
692 statp->_u._ext.ext = NULL;
693 }
694
695 const char *
res_get_nibblesuffix(res_state statp)696 res_get_nibblesuffix(res_state statp)
697 {
698 if (statp->_u._ext.ext)
699 return (statp->_u._ext.ext->nsuffix);
700 return ("ip6.arpa");
701 }
702
703 const char *
res_get_nibblesuffix2(res_state statp)704 res_get_nibblesuffix2(res_state statp)
705 {
706 if (statp->_u._ext.ext)
707 return (statp->_u._ext.ext->nsuffix2);
708 return ("ip6.int");
709 }
710
711 void
res_setservers(res_state statp,const union res_sockaddr_union * set,int cnt)712 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt)
713 {
714 int i, nserv;
715 size_t size;
716
717 /* close open servers */
718 res_nclose(statp);
719
720 /* cause rtt times to be forgotten */
721 statp->_u._ext.nscount = 0;
722
723 nserv = 0;
724 for (i = 0; i < cnt && nserv < MAXNS; i++) {
725 switch (set->sin.sin_family) {
726 case AF_INET:
727 size = sizeof(set->sin);
728 if (statp->_u._ext.ext)
729 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
730 &set->sin, size);
731 if (size <= sizeof(statp->nsaddr_list[nserv]))
732 memcpy(&statp->nsaddr_list[nserv],
733 &set->sin, size);
734 else
735 statp->nsaddr_list[nserv].sin_family = 0;
736 nserv++;
737 break;
738
739 #ifdef HAS_INET6_STRUCTS
740 case AF_INET6:
741 size = sizeof(set->sin6);
742 if (statp->_u._ext.ext)
743 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
744 &set->sin6, size);
745 if (size <= sizeof(statp->nsaddr_list[nserv]))
746 memcpy(&statp->nsaddr_list[nserv],
747 &set->sin6, size);
748 else
749 statp->nsaddr_list[nserv].sin_family = 0;
750 nserv++;
751 break;
752 #endif
753
754 default:
755 break;
756 }
757 set++;
758 }
759 statp->nscount = nserv;
760
761 }
762
763 int
res_getservers(res_state statp,union res_sockaddr_union * set,int cnt)764 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt)
765 {
766 int i;
767 size_t size;
768 uint16_t family;
769
770 for (i = 0; i < statp->nscount && i < cnt; i++) {
771 if (statp->_u._ext.ext)
772 family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
773 else
774 family = statp->nsaddr_list[i].sin_family;
775
776 switch (family) {
777 case AF_INET:
778 size = sizeof(set->sin);
779 if (statp->_u._ext.ext)
780 memcpy(&set->sin,
781 &statp->_u._ext.ext->nsaddrs[i],
782 size);
783 else
784 memcpy(&set->sin, &statp->nsaddr_list[i],
785 size);
786 break;
787
788 #ifdef HAS_INET6_STRUCTS
789 case AF_INET6:
790 size = sizeof(set->sin6);
791 if (statp->_u._ext.ext)
792 memcpy(&set->sin6,
793 &statp->_u._ext.ext->nsaddrs[i],
794 size);
795 else
796 memcpy(&set->sin6, &statp->nsaddr_list[i],
797 size);
798 break;
799 #endif
800
801 default:
802 set->sin.sin_family = 0;
803 break;
804 }
805 set++;
806 }
807 return (statp->nscount);
808 }
809
810 #ifdef ANDROID_CHANGES
res_setnetid(res_state statp,unsigned netid)811 void res_setnetid(res_state statp, unsigned netid)
812 {
813 if (statp != NULL) {
814 statp->netid = netid;
815 }
816 }
817
res_setmark(res_state statp,unsigned mark)818 void res_setmark(res_state statp, unsigned mark)
819 {
820 if (statp != NULL) {
821 statp->_mark = mark;
822 }
823 }
824
825 #endif /* ANDROID_CHANGES */
826