1 /* $NetBSD: res_init.c,v 1.8 2006/03/19 03:10:08 christos Exp $ */
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 */
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 */
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 */
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 */
85 #include <sys/types.h>
86 #include <sys/param.h>
87 #include <sys/socket.h>
88 #include <sys/time.h>
90 #include <netinet/in.h>
91 #include <arpa/inet.h>
92 #include "arpa_nameser.h"
94 #include <ctype.h>
95 #include <stdio.h>
96 #include <stdlib.h>
97 #include <string.h>
98 #include <unistd.h>
99 #include <netdb.h>
101 #ifdef ANDROID_CHANGES
102 #include <errno.h>
103 #include <fcntl.h>
104 #include <sys/system_properties.h>
105 #endif /* ANDROID_CHANGES */
107 #ifndef MIN
108 #define MIN(x,y) ((x)<(y)?(x):(y))
109 #endif
111 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
112 #ifdef ANDROID_CHANGES
113 #include "resolv_private.h"
114 #else
115 #include <resolv.h>
116 #endif
118 #include "res_private.h"
120 /* Options. Should all be left alone. */
121 #ifndef DEBUG
122 #define DEBUG
123 #endif
125 static void res_setoptions __P((res_state, const char *, const char *));
127 static const char sort_mask[] = "/&";
128 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
129 static u_int32_t net_mask __P((struct in_addr));
131 #if !defined(isascii) /* XXX - could be a function */
132 # define isascii(c) (!(c & 0200))
133 #endif
135 /*
136 * Resolver state default settings.
137 */
139 /*
140 * Set up default settings. If the configuration file exist, the values
141 * there will have precedence. Otherwise, the server address is set to
142 * INADDR_ANY and the default domain name comes from the gethostname().
143 *
144 * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
145 * rather than INADDR_ANY ("0.0.0.0") as the default name server address
146 * since it was noted that INADDR_ANY actually meant ``the first interface
147 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
148 * it had to be "up" in order for you to reach your own name server. It
149 * was later decided that since the recommended practice is to always
150 * install local static routes through 127.0.0.1 for all your network
151 * interfaces, that we could solve this problem without a code change.
152 *
153 * The configuration file should always be used, since it is the only way
154 * to specify a default domain. If you are running a server on your local
155 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
156 * in the configuration file.
157 *
158 * Return 0 if completes successfully, -1 on error
159 */
160 int
161 res_ninit(res_state statp) {
162 extern int __res_vinit(res_state, int);
164 return (__res_vinit(statp, 0));
165 }
167 /* This function has to be reachable by res_data.c but not publicly. */
168 int
169 __res_vinit(res_state statp, int preinit) {
170 register FILE *fp;
171 register char *cp, **pp;
172 register int n;
173 char buf[BUFSIZ];
174 int nserv = 0; /* number of nameserver records read from file */
175 int haveenv = 0;
176 int havesearch = 0;
177 int nsort = 0;
178 char *net;
179 int dots;
180 union res_sockaddr_union u[2];
182 if ((statp->options & RES_INIT) != 0U)
183 res_ndestroy(statp);
185 if (!preinit) {
186 statp->retrans = RES_TIMEOUT;
187 statp->retry = RES_DFLRETRY;
188 statp->options = RES_DEFAULT;
189 statp->id = res_randomid();
190 }
192 memset(u, 0, sizeof(u));
193 #ifdef USELOOPBACK
194 u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
195 #else
196 u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
197 #endif
198 u[nserv].sin.sin_family = AF_INET;
199 u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
200 #ifdef HAVE_SA_LEN
201 u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
202 #endif
203 nserv++;
204 #ifdef HAS_INET6_STRUCTS
205 #ifdef USELOOPBACK
206 u[nserv].sin6.sin6_addr = in6addr_loopback;
207 #else
208 u[nserv].sin6.sin6_addr = in6addr_any;
209 #endif
210 u[nserv].sin6.sin6_family = AF_INET6;
211 u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
212 #ifdef HAVE_SA_LEN
213 u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
214 #endif
215 nserv++;
216 #endif
217 statp->nscount = 0;
218 statp->ndots = 1;
219 statp->pfcode = 0;
220 statp->_vcsock = -1;
221 statp->_flags = 0;
222 statp->qhook = NULL;
223 statp->rhook = NULL;
224 statp->_u._ext.nscount = 0;
225 statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
226 if (statp->_u._ext.ext != NULL) {
227 memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
228 statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
229 strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
230 strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
231 }
232 statp->nsort = 0;
233 res_setservers(statp, u, nserv);
235 #if 0 /* IGNORE THE ENVIRONMENT */
236 /* Allow user to override the local domain definition */
237 if ((cp = getenv("LOCALDOMAIN")) != NULL) {
238 (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
239 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
240 haveenv++;
242 /*
243 * Set search list to be blank-separated strings
244 * from rest of env value. Permits users of LOCALDOMAIN
245 * to still have a search list, and anyone to set the
246 * one that they want to use as an individual (even more
247 * important now that the rfc1535 stuff restricts searches)
248 */
249 cp = statp->defdname;
250 pp = statp->dnsrch;
251 *pp++ = cp;
252 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
253 if (*cp == '\n') /* silly backwards compat */
254 break;
255 else if (*cp == ' ' || *cp == '\t') {
256 *cp = 0;
257 n = 1;
258 } else if (n) {
259 *pp++ = cp;
260 n = 0;
261 havesearch = 1;
262 }
263 }
264 /* null terminate last domain if there are excess */
265 while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
266 cp++;
267 *cp = '\0';
268 *pp++ = 0;
269 }
270 if (nserv > 0)
271 statp->nscount = nserv;
272 #endif
274 #ifndef ANDROID_CHANGES /* !ANDROID_CHANGES - IGNORE resolv.conf in Android */
275 #define MATCH(line, name) \
276 (!strncmp(line, name, sizeof(name) - 1) && \
277 (line[sizeof(name) - 1] == ' ' || \
278 line[sizeof(name) - 1] == '\t'))
280 nserv = 0;
281 if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
282 /* read the config file */
283 while (fgets(buf, sizeof(buf), fp) != NULL) {
284 /* skip comments */
285 if (*buf == ';' || *buf == '#')
286 continue;
287 /* read default domain name */
288 if (MATCH(buf, "domain")) {
289 if (haveenv) /* skip if have from environ */
290 continue;
291 cp = buf + sizeof("domain") - 1;
292 while (*cp == ' ' || *cp == '\t')
293 cp++;
294 if ((*cp == '\0') || (*cp == '\n'))
295 continue;
296 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
297 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
298 if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
299 *cp = '\0';
300 havesearch = 0;
301 continue;
302 }
303 /* set search list */
304 if (MATCH(buf, "search")) {
305 if (haveenv) /* skip if have from environ */
306 continue;
307 cp = buf + sizeof("search") - 1;
308 while (*cp == ' ' || *cp == '\t')
309 cp++;
310 if ((*cp == '\0') || (*cp == '\n'))
311 continue;
312 strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
313 statp->defdname[sizeof(statp->defdname) - 1] = '\0';
314 if ((cp = strchr(statp->defdname, '\n')) != NULL)
315 *cp = '\0';
316 /*
317 * Set search list to be blank-separated strings
318 * on rest of line.
319 */
320 cp = statp->defdname;
321 pp = statp->dnsrch;
322 *pp++ = cp;
323 for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
324 if (*cp == ' ' || *cp == '\t') {
325 *cp = 0;
326 n = 1;
327 } else if (n) {
328 *pp++ = cp;
329 n = 0;
330 }
331 }
332 /* null terminate last domain if there are excess */
333 while (*cp != '\0' && *cp != ' ' && *cp != '\t')
334 cp++;
335 *cp = '\0';
336 *pp++ = 0;
337 havesearch = 1;
338 continue;
339 }
340 /* read nameservers to query */
341 if (MATCH(buf, "nameserver") && nserv < MAXNS) {
342 struct addrinfo hints, *ai;
343 char sbuf[NI_MAXSERV];
344 const size_t minsiz =
345 sizeof(statp->_u._ext.ext->nsaddrs[0]);
347 cp = buf + sizeof("nameserver") - 1;
348 while (*cp == ' ' || *cp == '\t')
349 cp++;
350 cp[strcspn(cp, ";# \t\n")] = '\0';
351 if ((*cp != '\0') && (*cp != '\n')) {
352 memset(&hints, 0, sizeof(hints));
353 hints.ai_family = PF_UNSPEC;
354 hints.ai_socktype = SOCK_DGRAM; /*dummy*/
355 hints.ai_flags = AI_NUMERICHOST;
356 sprintf(sbuf, "%u", NAMESERVER_PORT);
357 if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
358 ai->ai_addrlen <= minsiz) {
359 if (statp->_u._ext.ext != NULL) {
360 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
361 ai->ai_addr, ai->ai_addrlen);
362 }
363 if (ai->ai_addrlen <=
364 sizeof(statp->nsaddr_list[nserv])) {
365 memcpy(&statp->nsaddr_list[nserv],
366 ai->ai_addr, ai->ai_addrlen);
367 } else
368 statp->nsaddr_list[nserv].sin_family = 0;
369 freeaddrinfo(ai);
370 nserv++;
371 }
372 }
373 continue;
374 }
375 if (MATCH(buf, "sortlist")) {
376 struct in_addr a;
378 cp = buf + sizeof("sortlist") - 1;
379 while (nsort < MAXRESOLVSORT) {
380 while (*cp == ' ' || *cp == '\t')
381 cp++;
382 if (*cp == '\0' || *cp == '\n' || *cp == ';')
383 break;
384 net = cp;
385 while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
386 isascii(*cp) && !isspace((unsigned char)*cp))
387 cp++;
388 n = *cp;
389 *cp = 0;
390 if (inet_aton(net, &a)) {
391 statp->sort_list[nsort].addr = a;
392 if (ISSORTMASK(n)) {
393 *cp++ = n;
394 net = cp;
395 while (*cp && *cp != ';' &&
396 isascii(*cp) &&
397 !isspace((unsigned char)*cp))
398 cp++;
399 n = *cp;
400 *cp = 0;
401 if (inet_aton(net, &a)) {
402 statp->sort_list[nsort].mask = a.s_addr;
403 } else {
404 statp->sort_list[nsort].mask =
405 net_mask(statp->sort_list[nsort].addr);
406 }
407 } else {
408 statp->sort_list[nsort].mask =
409 net_mask(statp->sort_list[nsort].addr);
410 }
411 nsort++;
412 }
413 *cp = n;
414 }
415 continue;
416 }
417 if (MATCH(buf, "options")) {
418 res_setoptions(statp, buf + sizeof("options") - 1, "conf");
419 continue;
420 }
421 }
422 if (nserv > 0)
423 statp->nscount = nserv;
424 statp->nsort = nsort;
425 (void) fclose(fp);
426 }
427 #endif /* !ANDROID_CHANGES */
428 /*
429 * Last chance to get a nameserver. This should not normally
430 * be necessary
431 */
432 #ifdef NO_RESOLV_CONF
433 if(nserv == 0)
434 nserv = get_nameservers(statp);
435 #endif
437 if (statp->defdname[0] == 0 &&
438 gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
439 (cp = strchr(buf, '.')) != NULL)
440 strcpy(statp->defdname, cp + 1);
442 /* find components of local domain that might be searched */
443 if (havesearch == 0) {
444 pp = statp->dnsrch;
445 *pp++ = statp->defdname;
446 *pp = NULL;
448 dots = 0;
449 for (cp = statp->defdname; *cp; cp++)
450 dots += (*cp == '.');
452 cp = statp->defdname;
453 while (pp < statp->dnsrch + MAXDFLSRCH) {
454 if (dots < LOCALDOMAINPARTS)
455 break;
456 cp = strchr(cp, '.') + 1; /* we know there is one */
457 *pp++ = cp;
458 dots--;
459 }
460 *pp = NULL;
461 #ifdef DEBUG
462 if (statp->options & RES_DEBUG) {
463 printf(";; res_init()... default dnsrch list:\n");
464 for (pp = statp->dnsrch; *pp; pp++)
465 printf(";;\t%s\n", *pp);
466 printf(";;\t..END..\n");
467 }
468 #endif
469 }
471 if ((cp = getenv("RES_OPTIONS")) != NULL)
472 res_setoptions(statp, cp, "env");
473 if (nserv > 0) {
474 statp->nscount = nserv;
475 statp->options |= RES_INIT;
476 }
477 return (0);
478 }
480 static void
481 res_setoptions(res_state statp, const char *options, const char *source)
482 {
483 const char *cp = options;
484 int i;
485 struct __res_state_ext *ext = statp->_u._ext.ext;
487 #ifdef DEBUG
488 if (statp->options & RES_DEBUG)
489 printf(";; res_setoptions(\"%s\", \"%s\")...\n",
490 options, source);
491 #endif
492 while (*cp) {
493 /* skip leading and inner runs of spaces */
494 while (*cp == ' ' || *cp == '\t')
495 cp++;
496 /* search for and process individual options */
497 if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
498 i = atoi(cp + sizeof("ndots:") - 1);
499 if (i <= RES_MAXNDOTS)
500 statp->ndots = i;
501 else
502 statp->ndots = RES_MAXNDOTS;
503 #ifdef DEBUG
504 if (statp->options & RES_DEBUG)
505 printf(";;\tndots=%d\n", statp->ndots);
506 #endif
507 } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
508 i = atoi(cp + sizeof("timeout:") - 1);
509 if (i <= RES_MAXRETRANS)
510 statp->retrans = i;
511 else
512 statp->retrans = RES_MAXRETRANS;
513 #ifdef DEBUG
514 if (statp->options & RES_DEBUG)
515 printf(";;\ttimeout=%d\n", statp->retrans);
516 #endif
517 } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
518 i = atoi(cp + sizeof("attempts:") - 1);
519 if (i <= RES_MAXRETRY)
520 statp->retry = i;
521 else
522 statp->retry = RES_MAXRETRY;
523 #ifdef DEBUG
524 if (statp->options & RES_DEBUG)
525 printf(";;\tattempts=%d\n", statp->retry);
526 #endif
527 } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
528 #ifdef DEBUG
529 if (!(statp->options & RES_DEBUG)) {
530 printf(";; res_setoptions(\"%s\", \"%s\")..\n",
531 options, source);
532 statp->options |= RES_DEBUG;
533 }
534 printf(";;\tdebug\n");
535 #endif
536 } else if (!strncmp(cp, "no_tld_query",
537 sizeof("no_tld_query") - 1) ||
538 !strncmp(cp, "no-tld-query",
539 sizeof("no-tld-query") - 1)) {
540 statp->options |= RES_NOTLDQUERY;
541 } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
542 statp->options |= RES_USE_INET6;
543 } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
544 statp->options |= RES_ROTATE;
545 } else if (!strncmp(cp, "no-check-names",
546 sizeof("no-check-names") - 1)) {
547 statp->options |= RES_NOCHECKNAME;
548 }
549 #ifdef RES_USE_EDNS0
550 else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
551 statp->options |= RES_USE_EDNS0;
552 }
553 #endif
554 else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
555 statp->options |= RES_USE_DNAME;
556 }
557 else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
558 if (ext == NULL)
559 goto skip;
560 cp += sizeof("nibble:") - 1;
561 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
562 strncpy(ext->nsuffix, cp, (size_t)i);
563 ext->nsuffix[i] = '\0';
564 }
565 else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
566 if (ext == NULL)
567 goto skip;
568 cp += sizeof("nibble2:") - 1;
569 i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
570 strncpy(ext->nsuffix2, cp, (size_t)i);
571 ext->nsuffix2[i] = '\0';
572 }
573 else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
574 cp += sizeof("v6revmode:") - 1;
575 /* "nibble" and "bitstring" used to be valid */
576 if (!strncmp(cp, "single", sizeof("single") - 1)) {
577 statp->options |= RES_NO_NIBBLE2;
578 } else if (!strncmp(cp, "both", sizeof("both") - 1)) {
579 statp->options &=
580 ~RES_NO_NIBBLE2;
581 }
582 }
583 else {
584 /* XXX - print a warning here? */
585 }
586 skip:
587 /* skip to next run of spaces */
588 while (*cp && *cp != ' ' && *cp != '\t')
589 cp++;
590 }
591 }
593 /* XXX - should really support CIDR which means explicit masks always. */
594 static u_int32_t
595 net_mask(in) /* XXX - should really use system's version of this */
596 struct in_addr in;
597 {
598 register u_int32_t i = ntohl(in.s_addr);
600 if (IN_CLASSA(i))
601 return (htonl(IN_CLASSA_NET));
602 else if (IN_CLASSB(i))
603 return (htonl(IN_CLASSB_NET));
604 return (htonl(IN_CLASSC_NET));
605 }
607 #ifdef ANDROID_CHANGES
608 static int
609 real_randomid(u_int *random_value) {
610 /* open the nonblocking random device, returning -1 on failure */
611 int random_device = open("/dev/urandom", O_RDONLY);
612 if (random_device < 0) {
613 return -1;
614 }
616 /* read from the random device, returning -1 on failure (or too many retries)*/
617 u_int retry = 5;
618 for (retry; retry > 0; retry--) {
619 int retval = read(random_device, random_value, sizeof(u_int));
620 if (retval == sizeof(u_int)) {
621 *random_value &= 0xffff;
622 close(random_device);
623 return 0;
624 } else if ((retval < 0) && (errno != EINTR)) {
625 break;
626 }
627 }
629 close(random_device);
630 return -1;
631 }
632 #endif /* ANDROID_CHANGES */
634 u_int
635 res_randomid(void) {
636 #ifdef ANDROID_CHANGES
637 int status = 0;
638 u_int output = 0;
639 status = real_randomid(&output);
640 if (status != -1) {
641 return output;
642 }
643 #endif /* ANDROID_CHANGES */
644 struct timeval now;
645 gettimeofday(&now, NULL);
646 return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));
647 }
649 /*
650 * This routine is for closing the socket if a virtual circuit is used and
651 * the program wants to close it. This provides support for endhostent()
652 * which expects to close the socket.
653 *
654 * This routine is not expected to be user visible.
655 */
656 void
657 res_nclose(res_state statp) {
658 int ns;
660 if (statp->_vcsock >= 0) {
661 (void) close(statp->_vcsock);
662 statp->_vcsock = -1;
663 statp->_flags &= ~(RES_F_VC | RES_F_CONN);
664 }
665 for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
666 if (statp->_u._ext.nssocks[ns] != -1) {
667 (void) close(statp->_u._ext.nssocks[ns]);
668 statp->_u._ext.nssocks[ns] = -1;
669 }
670 }
671 }
673 void
674 res_ndestroy(res_state statp) {
675 res_nclose(statp);
676 if (statp->_u._ext.ext != NULL)
677 free(statp->_u._ext.ext);
678 statp->options &= ~RES_INIT;
679 statp->_u._ext.ext = NULL;
680 }
682 const char *
683 res_get_nibblesuffix(res_state statp) {
684 if (statp->_u._ext.ext)
685 return (statp->_u._ext.ext->nsuffix);
686 return ("ip6.arpa");
687 }
689 const char *
690 res_get_nibblesuffix2(res_state statp) {
691 if (statp->_u._ext.ext)
692 return (statp->_u._ext.ext->nsuffix2);
693 return ("ip6.int");
694 }
696 void
697 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
698 int i, nserv;
699 size_t size;
701 /* close open servers */
702 res_nclose(statp);
704 /* cause rtt times to be forgotten */
705 statp->_u._ext.nscount = 0;
707 nserv = 0;
708 for (i = 0; i < cnt && nserv < MAXNS; i++) {
709 switch (set->sin.sin_family) {
710 case AF_INET:
711 size = sizeof(set->sin);
712 if (statp->_u._ext.ext)
713 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
714 &set->sin, size);
715 if (size <= sizeof(statp->nsaddr_list[nserv]))
716 memcpy(&statp->nsaddr_list[nserv],
717 &set->sin, size);
718 #ifdef notdef
719 else
720 statp->nsaddr_list[nserv].sin_family = 0;
721 #endif
722 nserv++;
723 break;
725 #ifdef HAS_INET6_STRUCTS
726 case AF_INET6:
727 size = sizeof(set->sin6);
728 if (statp->_u._ext.ext)
729 memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
730 &set->sin6, size);
731 if (size <= sizeof(statp->nsaddr_list[nserv]))
732 memcpy(&statp->nsaddr_list[nserv],
733 &set->sin6, size);
734 else
735 statp->nsaddr_list[nserv].sin_family = 0;
736 nserv++;
737 break;
738 #endif
740 default:
741 break;
742 }
743 set++;
744 }
745 statp->nscount = nserv;
747 }
749 int
750 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
751 int i;
752 size_t size;
753 u_int16_t family;
755 for (i = 0; i < statp->nscount && i < cnt; i++) {
756 if (statp->_u._ext.ext)
757 family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
758 else
759 family = statp->nsaddr_list[i].sin_family;
761 switch (family) {
762 case AF_INET:
763 size = sizeof(set->sin);
764 if (statp->_u._ext.ext)
765 memcpy(&set->sin,
766 &statp->_u._ext.ext->nsaddrs[i],
767 size);
768 else
769 memcpy(&set->sin, &statp->nsaddr_list[i],
770 size);
771 break;
773 #ifdef HAS_INET6_STRUCTS
774 case AF_INET6:
775 size = sizeof(set->sin6);
776 if (statp->_u._ext.ext)
777 memcpy(&set->sin6,
778 &statp->_u._ext.ext->nsaddrs[i],
779 size);
780 else
781 memcpy(&set->sin6, &statp->nsaddr_list[i],
782 size);
783 break;
784 #endif
786 default:
787 set->sin.sin_family = 0;
788 break;
789 }
790 set++;
791 }
792 return (statp->nscount);
793 }
795 #ifdef ANDROID_CHANGES
796 void res_setiface(res_state statp, const char* iface)
797 {
798 if (statp != NULL) {
799 // set interface
800 if (iface && iface[0] != '\0') {
801 int len = sizeof(statp->iface);
802 strncpy(statp->iface, iface, len - 1);
803 statp->iface[len - 1] = '\0';
804 } else {
805 statp->iface[0] = '\0';
806 }
807 }
808 }
810 void res_setmark(res_state statp, int mark)
811 {
812 if (statp != NULL) {
813 statp->_mark = mark;
814 }
815 }
816 #endif /* ANDROID_CHANGES */