xref: /freebsd/lib/libc/resolv/res_init.c (revision f0a75d274af375d15b97b830966b99a02b7db911)
1 /*
2  * Copyright (c) 1985, 1989, 1993
3  *    The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 /*
31  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
32  *
33  * Permission to use, copy, modify, and distribute this software for any
34  * purpose with or without fee is hereby granted, provided that the above
35  * copyright notice and this permission notice appear in all copies, and that
36  * the name of Digital Equipment Corporation not be used in advertising or
37  * publicity pertaining to distribution of the document or software without
38  * specific, written prior permission.
39  *
40  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
41  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
42  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
43  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
44  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
45  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
46  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
47  * SOFTWARE.
48  */
49 
50 /*
51  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
52  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
53  *
54  * Permission to use, copy, modify, and distribute this software for any
55  * purpose with or without fee is hereby granted, provided that the above
56  * copyright notice and this permission notice appear in all copies.
57  *
58  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
59  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
60  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
61  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
62  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
63  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
64  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
65  */
66 
67 #if defined(LIBC_SCCS) && !defined(lint)
68 static const char sccsid[] = "@(#)res_init.c	8.1 (Berkeley) 6/7/93";
69 static const char rcsid[] = "$Id: res_init.c,v 1.9.2.5.4.6 2006/08/30 23:23:01 marka Exp $";
70 #endif /* LIBC_SCCS and not lint */
71 #include <sys/cdefs.h>
72 __FBSDID("$FreeBSD$");
73 
74 #include "port_before.h"
75 
76 #include "namespace.h"
77 
78 #include <sys/types.h>
79 #include <sys/param.h>
80 #include <sys/socket.h>
81 #include <sys/time.h>
82 
83 #include <netinet/in.h>
84 #include <arpa/inet.h>
85 #include <arpa/nameser.h>
86 
87 #include <ctype.h>
88 #include <stdio.h>
89 #include <stdlib.h>
90 #include <string.h>
91 #include <unistd.h>
92 #include <netdb.h>
93 
94 #include "un-namespace.h"
95 
96 #include "port_after.h"
97 
98 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
99 #include <resolv.h>
100 
101 #include "res_private.h"
102 
103 /* Options.  Should all be left alone. */
104 #define RESOLVSORT
105 #define DEBUG
106 
107 #ifdef SOLARIS2
108 #include <sys/systeminfo.h>
109 #endif
110 
111 static void res_setoptions(res_state, const char *, const char *);
112 
113 #ifdef RESOLVSORT
114 static const char sort_mask[] = "/&";
115 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
116 static u_int32_t net_mask(struct in_addr);
117 #endif
118 
119 #if !defined(isascii)	/* XXX - could be a function */
120 # define isascii(c) (!(c & 0200))
121 #endif
122 
123 /*
124  * Resolver state default settings.
125  */
126 
127 /*
128  * Set up default settings.  If the configuration file exist, the values
129  * there will have precedence.  Otherwise, the server address is set to
130  * INADDR_ANY and the default domain name comes from the gethostname().
131  *
132  * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
133  * rather than INADDR_ANY ("0.0.0.0") as the default name server address
134  * since it was noted that INADDR_ANY actually meant ``the first interface
135  * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
136  * it had to be "up" in order for you to reach your own name server.  It
137  * was later decided that since the recommended practice is to always
138  * install local static routes through 127.0.0.1 for all your network
139  * interfaces, that we could solve this problem without a code change.
140  *
141  * The configuration file should always be used, since it is the only way
142  * to specify a default domain.  If you are running a server on your local
143  * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
144  * in the configuration file.
145  *
146  * Return 0 if completes successfully, -1 on error
147  */
148 int
149 res_ninit(res_state statp) {
150 	extern int __res_vinit(res_state, int);
151 
152 	return (__res_vinit(statp, 0));
153 }
154 
155 /* This function has to be reachable by res_data.c but not publically. */
156 int
157 __res_vinit(res_state statp, int preinit) {
158 	FILE *fp;
159 	char *cp, **pp;
160 	int n;
161 	char buf[BUFSIZ];
162 	int nserv = 0;    /* number of nameserver records read from file */
163 	int haveenv = 0;
164 	int havesearch = 0;
165 #ifdef RESOLVSORT
166 	int nsort = 0;
167 	char *net;
168 #endif
169 	int dots;
170 	union res_sockaddr_union u[2];
171 
172 	if (statp->_u._ext.ext != NULL)
173 		res_ndestroy(statp);
174 
175 	if (!preinit) {
176 		statp->retrans = RES_TIMEOUT;
177 		statp->retry = RES_DFLRETRY;
178 		statp->options = RES_DEFAULT;
179 		statp->id = res_randomid();
180 	}
181 
182 	memset(u, 0, sizeof(u));
183 #ifdef USELOOPBACK
184 	u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
185 #else
186 	u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
187 #endif
188 	u[nserv].sin.sin_family = AF_INET;
189 	u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
190 #ifdef HAVE_SA_LEN
191 	u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
192 #endif
193 	nserv++;
194 #ifdef HAS_INET6_STRUCTS
195 #ifdef USELOOPBACK
196 	u[nserv].sin6.sin6_addr = in6addr_loopback;
197 #else
198 	u[nserv].sin6.sin6_addr = in6addr_any;
199 #endif
200 	u[nserv].sin6.sin6_family = AF_INET6;
201 	u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
202 #ifdef HAVE_SA_LEN
203 	u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
204 #endif
205 	nserv++;
206 #endif
207 	statp->nscount = 0;
208 	statp->ndots = 1;
209 	statp->pfcode = 0;
210 	statp->_vcsock = -1;
211 	statp->_flags = 0;
212 	statp->qhook = NULL;
213 	statp->rhook = NULL;
214 	statp->_u._ext.nscount = 0;
215 	statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
216 	if (statp->_u._ext.ext != NULL) {
217 	        memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
218 		statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
219 		strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
220 		strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
221 	} else
222 		return (-1);
223 #ifdef RESOLVSORT
224 	statp->nsort = 0;
225 #endif
226 	res_setservers(statp, u, nserv);
227 
228 #ifdef	SOLARIS2
229 	/*
230 	 * The old libresolv derived the defaultdomain from NIS/NIS+.
231 	 * We want to keep this behaviour
232 	 */
233 	{
234 		char buf[sizeof(statp->defdname)], *cp;
235 		int ret;
236 
237 		if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 &&
238 			(unsigned int)ret <= sizeof(buf)) {
239 			if (buf[0] == '+')
240 				buf[0] = '.';
241 			cp = strchr(buf, '.');
242 			cp = (cp == NULL) ? buf : (cp + 1);
243 			if (strlen(cp) >= sizeof(statp->defdname))
244 				goto freedata;
245 			strcpy(statp->defdname, cp);
246 		}
247 	}
248 #endif	/* SOLARIS2 */
249 
250 	/* Allow user to override the local domain definition */
251 	if (issetugid() == 0 && (cp = getenv("LOCALDOMAIN")) != NULL) {
252 		(void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
253 		statp->defdname[sizeof(statp->defdname) - 1] = '\0';
254 		haveenv++;
255 
256 		/*
257 		 * Set search list to be blank-separated strings
258 		 * from rest of env value.  Permits users of LOCALDOMAIN
259 		 * to still have a search list, and anyone to set the
260 		 * one that they want to use as an individual (even more
261 		 * important now that the rfc1535 stuff restricts searches)
262 		 */
263 		cp = statp->defdname;
264 		pp = statp->dnsrch;
265 		*pp++ = cp;
266 		for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
267 			if (*cp == '\n')	/* silly backwards compat */
268 				break;
269 			else if (*cp == ' ' || *cp == '\t') {
270 				*cp = 0;
271 				n = 1;
272 			} else if (n) {
273 				*pp++ = cp;
274 				n = 0;
275 				havesearch = 1;
276 			}
277 		}
278 		/* null terminate last domain if there are excess */
279 		while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
280 			cp++;
281 		*cp = '\0';
282 		*pp++ = 0;
283 	}
284 
285 #define	MATCH(line, name) \
286 	(!strncmp(line, name, sizeof(name) - 1) && \
287 	(line[sizeof(name) - 1] == ' ' || \
288 	 line[sizeof(name) - 1] == '\t'))
289 
290 	nserv = 0;
291 	if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
292 	    /* read the config file */
293 	    while (fgets(buf, sizeof(buf), fp) != NULL) {
294 		/* skip comments */
295 		if (*buf == ';' || *buf == '#')
296 			continue;
297 		/* read default domain name */
298 		if (MATCH(buf, "domain")) {
299 		    if (haveenv)	/* skip if have from environ */
300 			    continue;
301 		    cp = buf + sizeof("domain") - 1;
302 		    while (*cp == ' ' || *cp == '\t')
303 			    cp++;
304 		    if ((*cp == '\0') || (*cp == '\n'))
305 			    continue;
306 		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
307 		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
308 		    if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
309 			    *cp = '\0';
310 		    havesearch = 0;
311 		    continue;
312 		}
313 		/* set search list */
314 		if (MATCH(buf, "search")) {
315 		    if (haveenv)	/* skip if have from environ */
316 			    continue;
317 		    cp = buf + sizeof("search") - 1;
318 		    while (*cp == ' ' || *cp == '\t')
319 			    cp++;
320 		    if ((*cp == '\0') || (*cp == '\n'))
321 			    continue;
322 		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
323 		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
324 		    if ((cp = strchr(statp->defdname, '\n')) != NULL)
325 			    *cp = '\0';
326 		    /*
327 		     * Set search list to be blank-separated strings
328 		     * on rest of line.
329 		     */
330 		    cp = statp->defdname;
331 		    pp = statp->dnsrch;
332 		    *pp++ = cp;
333 		    for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
334 			    if (*cp == ' ' || *cp == '\t') {
335 				    *cp = 0;
336 				    n = 1;
337 			    } else if (n) {
338 				    *pp++ = cp;
339 				    n = 0;
340 			    }
341 		    }
342 		    /* null terminate last domain if there are excess */
343 		    while (*cp != '\0' && *cp != ' ' && *cp != '\t')
344 			    cp++;
345 		    *cp = '\0';
346 		    *pp++ = 0;
347 		    havesearch = 1;
348 		    continue;
349 		}
350 		/* read nameservers to query */
351 		if (MATCH(buf, "nameserver") && nserv < MAXNS) {
352 		    struct addrinfo hints, *ai;
353 		    char sbuf[NI_MAXSERV];
354 		    const size_t minsiz =
355 		        sizeof(statp->_u._ext.ext->nsaddrs[0]);
356 
357 		    cp = buf + sizeof("nameserver") - 1;
358 		    while (*cp == ' ' || *cp == '\t')
359 			cp++;
360 		    cp[strcspn(cp, ";# \t\n")] = '\0';
361 		    if ((*cp != '\0') && (*cp != '\n')) {
362 			memset(&hints, 0, sizeof(hints));
363 			hints.ai_family = PF_UNSPEC;
364 			hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
365 			hints.ai_flags = AI_NUMERICHOST;
366 			sprintf(sbuf, "%u", NAMESERVER_PORT);
367 			if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
368 			    ai->ai_addrlen <= minsiz) {
369 			    if (statp->_u._ext.ext != NULL) {
370 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
371 				    ai->ai_addr, ai->ai_addrlen);
372 			    }
373 			    if (ai->ai_addrlen <=
374 			        sizeof(statp->nsaddr_list[nserv])) {
375 				memcpy(&statp->nsaddr_list[nserv],
376 				    ai->ai_addr, ai->ai_addrlen);
377 			    } else
378 				statp->nsaddr_list[nserv].sin_family = 0;
379 			    freeaddrinfo(ai);
380 			    nserv++;
381 			}
382 		    }
383 		    continue;
384 		}
385 #ifdef RESOLVSORT
386 		if (MATCH(buf, "sortlist")) {
387 		    struct in_addr a;
388 		    struct in6_addr a6;
389 		    int m, i;
390 		    u_char *u;
391 		    struct __res_state_ext *ext = statp->_u._ext.ext;
392 
393 		    cp = buf + sizeof("sortlist") - 1;
394 		    while (nsort < MAXRESOLVSORT) {
395 			while (*cp == ' ' || *cp == '\t')
396 			    cp++;
397 			if (*cp == '\0' || *cp == '\n' || *cp == ';')
398 			    break;
399 			net = cp;
400 			while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
401 			       isascii(*cp) && !isspace((unsigned char)*cp))
402 				cp++;
403 			n = *cp;
404 			*cp = 0;
405 			if (inet_aton(net, &a)) {
406 			    statp->sort_list[nsort].addr = a;
407 			    if (ISSORTMASK(n)) {
408 				*cp++ = n;
409 				net = cp;
410 				while (*cp && *cp != ';' &&
411 					isascii(*cp) &&
412 					!isspace((unsigned char)*cp))
413 				    cp++;
414 				n = *cp;
415 				*cp = 0;
416 				if (inet_aton(net, &a)) {
417 				    statp->sort_list[nsort].mask = a.s_addr;
418 				} else {
419 				    statp->sort_list[nsort].mask =
420 					net_mask(statp->sort_list[nsort].addr);
421 				}
422 			    } else {
423 				statp->sort_list[nsort].mask =
424 				    net_mask(statp->sort_list[nsort].addr);
425 			    }
426 			    ext->sort_list[nsort].af = AF_INET;
427 			    ext->sort_list[nsort].addr.ina =
428 				statp->sort_list[nsort].addr;
429 			    ext->sort_list[nsort].mask.ina.s_addr =
430 				statp->sort_list[nsort].mask;
431 			    nsort++;
432 			}
433 			else if (inet_pton(AF_INET6, net, &a6) == 1) {
434 
435 			    ext->sort_list[nsort].af = AF_INET6;
436 			    ext->sort_list[nsort].addr.in6a = a6;
437 			    u = (u_char *)&ext->sort_list[nsort].mask.in6a;
438 			    *cp++ = n;
439 			    net = cp;
440 			    while (*cp && *cp != ';' &&
441 				    isascii(*cp) && !isspace(*cp))
442 				cp++;
443 			    m = n;
444 			    n = *cp;
445 			    *cp = 0;
446 			    switch (m) {
447 			    case '/':
448 				m = atoi(net);
449 				break;
450 			    case '&':
451 				if (inet_pton(AF_INET6, net, u) == 1) {
452 				    m = -1;
453 				    break;
454 				}
455 				/*FALLTHROUGH*/
456 			    default:
457 				m = sizeof(struct in6_addr) * CHAR_BIT;
458 				break;
459 			    }
460 			    if (m >= 0) {
461 				for (i = 0; i < sizeof(struct in6_addr); i++) {
462 				    if (m <= 0) {
463 					*u = 0;
464 				    } else {
465 					m -= CHAR_BIT;
466 					*u = (u_char)~0;
467 					if (m < 0)
468 					    *u <<= -m;
469 				    }
470 				    u++;
471 				}
472 			    }
473 			    statp->sort_list[nsort].addr.s_addr =
474 				(u_int32_t)0xffffffff;
475 			    statp->sort_list[nsort].mask =
476 				(u_int32_t)0xffffffff;
477 			    nsort++;
478 			}
479 			*cp = n;
480 		    }
481 		    continue;
482 		}
483 #endif
484 		if (MATCH(buf, "options")) {
485 		    res_setoptions(statp, buf + sizeof("options") - 1, "conf");
486 		    continue;
487 		}
488 	    }
489 	    if (nserv > 0)
490 		statp->nscount = nserv;
491 #ifdef RESOLVSORT
492 	    statp->nsort = nsort;
493 #endif
494 	    (void) fclose(fp);
495 	}
496 /*
497  * Last chance to get a nameserver.  This should not normally
498  * be necessary
499  */
500 #ifdef NO_RESOLV_CONF
501 	if(nserv == 0)
502 		nserv = get_nameservers(statp);
503 #endif
504 
505 	if (statp->defdname[0] == 0 &&
506 	    gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
507 	    (cp = strchr(buf, '.')) != NULL)
508 		strcpy(statp->defdname, cp + 1);
509 
510 	/* find components of local domain that might be searched */
511 	if (havesearch == 0) {
512 		pp = statp->dnsrch;
513 		*pp++ = statp->defdname;
514 		*pp = NULL;
515 
516 		dots = 0;
517 		for (cp = statp->defdname; *cp; cp++)
518 			dots += (*cp == '.');
519 
520 		cp = statp->defdname;
521 		while (pp < statp->dnsrch + MAXDFLSRCH) {
522 			if (dots < LOCALDOMAINPARTS)
523 				break;
524 			cp = strchr(cp, '.') + 1;    /* we know there is one */
525 			*pp++ = cp;
526 			dots--;
527 		}
528 		*pp = NULL;
529 #ifdef DEBUG
530 		if (statp->options & RES_DEBUG) {
531 			printf(";; res_init()... default dnsrch list:\n");
532 			for (pp = statp->dnsrch; *pp; pp++)
533 				printf(";;\t%s\n", *pp);
534 			printf(";;\t..END..\n");
535 		}
536 #endif
537 	}
538 
539 	if (issetugid())
540 		statp->options |= RES_NOALIASES;
541 	else if ((cp = getenv("RES_OPTIONS")) != NULL)
542 		res_setoptions(statp, cp, "env");
543 	statp->options |= RES_INIT;
544 	return (0);
545 
546 #ifdef	SOLARIS2
547  freedata:
548 	if (statp->_u._ext.ext != NULL) {
549 		free(statp->_u._ext.ext);
550 		statp->_u._ext.ext = NULL;
551 	}
552 	return (-1);
553 #endif
554 }
555 
556 static void
557 res_setoptions(res_state statp, const char *options, const char *source)
558 {
559 	const char *cp = options;
560 	int i;
561 #ifndef _LIBC
562 	struct __res_state_ext *ext = statp->_u._ext.ext;
563 #endif
564 
565 #ifdef DEBUG
566 	if (statp->options & RES_DEBUG)
567 		printf(";; res_setoptions(\"%s\", \"%s\")...\n",
568 		       options, source);
569 #endif
570 	while (*cp) {
571 		/* skip leading and inner runs of spaces */
572 		while (*cp == ' ' || *cp == '\t')
573 			cp++;
574 		/* search for and process individual options */
575 		if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
576 			i = atoi(cp + sizeof("ndots:") - 1);
577 			if (i <= RES_MAXNDOTS)
578 				statp->ndots = i;
579 			else
580 				statp->ndots = RES_MAXNDOTS;
581 #ifdef DEBUG
582 			if (statp->options & RES_DEBUG)
583 				printf(";;\tndots=%d\n", statp->ndots);
584 #endif
585 		} else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
586 			i = atoi(cp + sizeof("timeout:") - 1);
587 			if (i <= RES_MAXRETRANS)
588 				statp->retrans = i;
589 			else
590 				statp->retrans = RES_MAXRETRANS;
591 #ifdef DEBUG
592 			if (statp->options & RES_DEBUG)
593 				printf(";;\ttimeout=%d\n", statp->retrans);
594 #endif
595 #ifdef	SOLARIS2
596 		} else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) {
597 			/*
598 		 	 * For backward compatibility, 'retrans' is
599 		 	 * supported as an alias for 'timeout', though
600 		 	 * without an imposed maximum.
601 		 	 */
602 			statp->retrans = atoi(cp + sizeof("retrans:") - 1);
603 		} else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){
604 			/*
605 			 * For backward compatibility, 'retry' is
606 			 * supported as an alias for 'attempts', though
607 			 * without an imposed maximum.
608 			 */
609 			statp->retry = atoi(cp + sizeof("retry:") - 1);
610 #endif	/* SOLARIS2 */
611 		} else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
612 			i = atoi(cp + sizeof("attempts:") - 1);
613 			if (i <= RES_MAXRETRY)
614 				statp->retry = i;
615 			else
616 				statp->retry = RES_MAXRETRY;
617 #ifdef DEBUG
618 			if (statp->options & RES_DEBUG)
619 				printf(";;\tattempts=%d\n", statp->retry);
620 #endif
621 		} else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
622 #ifdef DEBUG
623 			if (!(statp->options & RES_DEBUG)) {
624 				printf(";; res_setoptions(\"%s\", \"%s\")..\n",
625 				       options, source);
626 				statp->options |= RES_DEBUG;
627 			}
628 			printf(";;\tdebug\n");
629 #endif
630 		} else if (!strncmp(cp, "no_tld_query",
631 				    sizeof("no_tld_query") - 1) ||
632 			   !strncmp(cp, "no-tld-query",
633 				    sizeof("no-tld-query") - 1)) {
634 			statp->options |= RES_NOTLDQUERY;
635 		} else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
636 			statp->options |= RES_USE_INET6;
637 		} else if (!strncmp(cp, "insecure1", sizeof("insecure1") - 1)) {
638 		       statp->options |= RES_INSECURE1;
639 		} else if (!strncmp(cp, "insecure2", sizeof("insecure2") - 1)) {
640 		       statp->options |= RES_INSECURE2;
641 		} else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
642 			statp->options |= RES_ROTATE;
643 		} else if (!strncmp(cp, "no-check-names",
644 				    sizeof("no-check-names") - 1)) {
645 			statp->options |= RES_NOCHECKNAME;
646 		}
647 #ifdef RES_USE_EDNS0
648 		else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
649 			statp->options |= RES_USE_EDNS0;
650 		}
651 #endif
652 #ifndef _LIBC
653 		else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
654 			statp->options |= RES_USE_DNAME;
655 		}
656 		else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
657 			if (ext == NULL)
658 				goto skip;
659 			cp += sizeof("nibble:") - 1;
660 			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
661 			strncpy(ext->nsuffix, cp, i);
662 			ext->nsuffix[i] = '\0';
663 		}
664 		else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
665 			if (ext == NULL)
666 				goto skip;
667 			cp += sizeof("nibble2:") - 1;
668 			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
669 			strncpy(ext->nsuffix2, cp, i);
670 			ext->nsuffix2[i] = '\0';
671 		}
672 		else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
673 			cp += sizeof("v6revmode:") - 1;
674 			/* "nibble" and "bitstring" used to be valid */
675 			if (!strncmp(cp, "single", sizeof("single") - 1)) {
676 				statp->options |= RES_NO_NIBBLE2;
677 			} else if (!strncmp(cp, "both", sizeof("both") - 1)) {
678 				statp->options &=
679 					 ~RES_NO_NIBBLE2;
680 			}
681 		}
682 #endif
683 		else {
684 			/* XXX - print a warning here? */
685 		}
686 #ifndef _LIBC
687    skip:
688 #endif
689 		/* skip to next run of spaces */
690 		while (*cp && *cp != ' ' && *cp != '\t')
691 			cp++;
692 	}
693 }
694 
695 #ifdef RESOLVSORT
696 /* XXX - should really support CIDR which means explicit masks always. */
697 static u_int32_t
698 net_mask(in)		/* XXX - should really use system's version of this */
699 	struct in_addr in;
700 {
701 	u_int32_t i = ntohl(in.s_addr);
702 
703 	if (IN_CLASSA(i))
704 		return (htonl(IN_CLASSA_NET));
705 	else if (IN_CLASSB(i))
706 		return (htonl(IN_CLASSB_NET));
707 	return (htonl(IN_CLASSC_NET));
708 }
709 #endif
710 
711 u_int
712 res_randomid(void) {
713 	struct timeval now;
714 
715 	gettimeofday(&now, NULL);
716 	return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));
717 }
718 
719 /*
720  * This routine is for closing the socket if a virtual circuit is used and
721  * the program wants to close it.  This provides support for endhostent()
722  * which expects to close the socket.
723  *
724  * This routine is not expected to be user visible.
725  */
726 void
727 res_nclose(res_state statp) {
728 	int ns;
729 
730 	if (statp->_vcsock >= 0) {
731 		(void) _close(statp->_vcsock);
732 		statp->_vcsock = -1;
733 		statp->_flags &= ~(RES_F_VC | RES_F_CONN);
734 	}
735 	for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
736 		if (statp->_u._ext.nssocks[ns] != -1) {
737 			(void) _close(statp->_u._ext.nssocks[ns]);
738 			statp->_u._ext.nssocks[ns] = -1;
739 		}
740 	}
741 }
742 
743 void
744 res_ndestroy(res_state statp) {
745 	res_nclose(statp);
746 	if (statp->_u._ext.ext != NULL)
747 		free(statp->_u._ext.ext);
748 	statp->options &= ~RES_INIT;
749 	statp->_u._ext.ext = NULL;
750 }
751 
752 #ifndef _LIBC
753 const char *
754 res_get_nibblesuffix(res_state statp) {
755 	if (statp->_u._ext.ext)
756 		return (statp->_u._ext.ext->nsuffix);
757 	return ("ip6.arpa");
758 }
759 
760 const char *
761 res_get_nibblesuffix2(res_state statp) {
762 	if (statp->_u._ext.ext)
763 		return (statp->_u._ext.ext->nsuffix2);
764 	return ("ip6.int");
765 }
766 #endif
767 
768 void
769 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
770 	int i, nserv;
771 	size_t size;
772 
773 	/* close open servers */
774 	res_nclose(statp);
775 
776 	/* cause rtt times to be forgotten */
777 	statp->_u._ext.nscount = 0;
778 
779 	nserv = 0;
780 	for (i = 0; i < cnt && nserv < MAXNS; i++) {
781 		switch (set->sin.sin_family) {
782 		case AF_INET:
783 			size = sizeof(set->sin);
784 			if (statp->_u._ext.ext)
785 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
786 					&set->sin, size);
787 			if (size <= sizeof(statp->nsaddr_list[nserv]))
788 				memcpy(&statp->nsaddr_list[nserv],
789 					&set->sin, size);
790 			else
791 				statp->nsaddr_list[nserv].sin_family = 0;
792 			nserv++;
793 			break;
794 
795 #ifdef HAS_INET6_STRUCTS
796 		case AF_INET6:
797 			size = sizeof(set->sin6);
798 			if (statp->_u._ext.ext)
799 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
800 					&set->sin6, size);
801 			if (size <= sizeof(statp->nsaddr_list[nserv]))
802 				memcpy(&statp->nsaddr_list[nserv],
803 					&set->sin6, size);
804 			else
805 				statp->nsaddr_list[nserv].sin_family = 0;
806 			nserv++;
807 			break;
808 #endif
809 
810 		default:
811 			break;
812 		}
813 		set++;
814 	}
815 	statp->nscount = nserv;
816 
817 }
818 
819 int
820 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
821 	int i;
822 	size_t size;
823 	u_int16_t family;
824 
825 	for (i = 0; i < statp->nscount && i < cnt; i++) {
826 		if (statp->_u._ext.ext)
827 			family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
828 		else
829 			family = statp->nsaddr_list[i].sin_family;
830 
831 		switch (family) {
832 		case AF_INET:
833 			size = sizeof(set->sin);
834 			if (statp->_u._ext.ext)
835 				memcpy(&set->sin,
836 				       &statp->_u._ext.ext->nsaddrs[i],
837 				       size);
838 			else
839 				memcpy(&set->sin, &statp->nsaddr_list[i],
840 				       size);
841 			break;
842 
843 #ifdef HAS_INET6_STRUCTS
844 		case AF_INET6:
845 			size = sizeof(set->sin6);
846 			if (statp->_u._ext.ext)
847 				memcpy(&set->sin6,
848 				       &statp->_u._ext.ext->nsaddrs[i],
849 				       size);
850 			else
851 				memcpy(&set->sin6, &statp->nsaddr_list[i],
852 				       size);
853 			break;
854 #endif
855 
856 		default:
857 			set->sin.sin_family = 0;
858 			break;
859 		}
860 		set++;
861 	}
862 	return (statp->nscount);
863 }
864