xref: /freebsd/lib/libc/resolv/res_init.c (revision f856af0466c076beef4ea9b15d088e1119a945b8)
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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  * 	This product includes software developed by the University of
16  * 	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 /*
35  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
36  *
37  * Permission to use, copy, modify, and distribute this software for any
38  * purpose with or without fee is hereby granted, provided that the above
39  * copyright notice and this permission notice appear in all copies, and that
40  * the name of Digital Equipment Corporation not be used in advertising or
41  * publicity pertaining to distribution of the document or software without
42  * specific, written prior permission.
43  *
44  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
45  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
46  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
47  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
48  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
49  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
50  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
51  * SOFTWARE.
52  */
53 
54 /*
55  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
56  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
57  *
58  * Permission to use, copy, modify, and distribute this software for any
59  * purpose with or without fee is hereby granted, provided that the above
60  * copyright notice and this permission notice appear in all copies.
61  *
62  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
63  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
64  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
65  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
66  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
67  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
68  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
69  */
70 
71 #if defined(LIBC_SCCS) && !defined(lint)
72 static const char sccsid[] = "@(#)res_init.c	8.1 (Berkeley) 6/7/93";
73 static const char rcsid[] = "$Id: res_init.c,v 1.9.2.5.4.6 2006/08/30 23:23:01 marka Exp $";
74 #endif /* LIBC_SCCS and not lint */
75 #include <sys/cdefs.h>
76 __FBSDID("$FreeBSD$");
77 
78 #include "port_before.h"
79 
80 #include "namespace.h"
81 
82 #include <sys/types.h>
83 #include <sys/param.h>
84 #include <sys/socket.h>
85 #include <sys/time.h>
86 
87 #include <netinet/in.h>
88 #include <arpa/inet.h>
89 #include <arpa/nameser.h>
90 
91 #include <ctype.h>
92 #include <stdio.h>
93 #include <stdlib.h>
94 #include <string.h>
95 #include <unistd.h>
96 #include <netdb.h>
97 
98 #include "un-namespace.h"
99 
100 #include "port_after.h"
101 
102 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
103 #include <resolv.h>
104 
105 #include "res_private.h"
106 
107 /* Options.  Should all be left alone. */
108 #define RESOLVSORT
109 #define DEBUG
110 
111 #ifdef SOLARIS2
112 #include <sys/systeminfo.h>
113 #endif
114 
115 static void res_setoptions(res_state, const char *, const char *);
116 
117 #ifdef RESOLVSORT
118 static const char sort_mask[] = "/&";
119 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
120 static u_int32_t net_mask(struct in_addr);
121 #endif
122 
123 #if !defined(isascii)	/* XXX - could be a function */
124 # define isascii(c) (!(c & 0200))
125 #endif
126 
127 /*
128  * Resolver state default settings.
129  */
130 
131 /*
132  * Set up default settings.  If the configuration file exist, the values
133  * there will have precedence.  Otherwise, the server address is set to
134  * INADDR_ANY and the default domain name comes from the gethostname().
135  *
136  * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
137  * rather than INADDR_ANY ("0.0.0.0") as the default name server address
138  * since it was noted that INADDR_ANY actually meant ``the first interface
139  * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
140  * it had to be "up" in order for you to reach your own name server.  It
141  * was later decided that since the recommended practice is to always
142  * install local static routes through 127.0.0.1 for all your network
143  * interfaces, that we could solve this problem without a code change.
144  *
145  * The configuration file should always be used, since it is the only way
146  * to specify a default domain.  If you are running a server on your local
147  * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
148  * in the configuration file.
149  *
150  * Return 0 if completes successfully, -1 on error
151  */
152 int
153 res_ninit(res_state statp) {
154 	extern int __res_vinit(res_state, int);
155 
156 	return (__res_vinit(statp, 0));
157 }
158 
159 /* This function has to be reachable by res_data.c but not publically. */
160 int
161 __res_vinit(res_state statp, int preinit) {
162 	FILE *fp;
163 	char *cp, **pp;
164 	int n;
165 	char buf[BUFSIZ];
166 	int nserv = 0;    /* number of nameserver records read from file */
167 	int haveenv = 0;
168 	int havesearch = 0;
169 #ifdef RESOLVSORT
170 	int nsort = 0;
171 	char *net;
172 #endif
173 	int dots;
174 	union res_sockaddr_union u[2];
175 
176 	if (statp->_u._ext.ext != NULL)
177 		res_ndestroy(statp);
178 
179 	if (!preinit) {
180 		statp->retrans = RES_TIMEOUT;
181 		statp->retry = RES_DFLRETRY;
182 		statp->options = RES_DEFAULT;
183 		statp->id = res_randomid();
184 	}
185 
186 	memset(u, 0, sizeof(u));
187 #ifdef USELOOPBACK
188 	u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
189 #else
190 	u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
191 #endif
192 	u[nserv].sin.sin_family = AF_INET;
193 	u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
194 #ifdef HAVE_SA_LEN
195 	u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
196 #endif
197 	nserv++;
198 #ifdef HAS_INET6_STRUCTS
199 #ifdef USELOOPBACK
200 	u[nserv].sin6.sin6_addr = in6addr_loopback;
201 #else
202 	u[nserv].sin6.sin6_addr = in6addr_any;
203 #endif
204 	u[nserv].sin6.sin6_family = AF_INET6;
205 	u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
206 #ifdef HAVE_SA_LEN
207 	u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
208 #endif
209 	nserv++;
210 #endif
211 	statp->nscount = 0;
212 	statp->ndots = 1;
213 	statp->pfcode = 0;
214 	statp->_vcsock = -1;
215 	statp->_flags = 0;
216 	statp->qhook = NULL;
217 	statp->rhook = NULL;
218 	statp->_u._ext.nscount = 0;
219 	statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
220 	if (statp->_u._ext.ext != NULL) {
221 	        memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
222 		statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
223 		strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
224 		strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
225 	} else
226 		return (-1);
227 #ifdef RESOLVSORT
228 	statp->nsort = 0;
229 #endif
230 	res_setservers(statp, u, nserv);
231 
232 #ifdef	SOLARIS2
233 	/*
234 	 * The old libresolv derived the defaultdomain from NIS/NIS+.
235 	 * We want to keep this behaviour
236 	 */
237 	{
238 		char buf[sizeof(statp->defdname)], *cp;
239 		int ret;
240 
241 		if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 &&
242 			(unsigned int)ret <= sizeof(buf)) {
243 			if (buf[0] == '+')
244 				buf[0] = '.';
245 			cp = strchr(buf, '.');
246 			cp = (cp == NULL) ? buf : (cp + 1);
247 			if (strlen(cp) >= sizeof(statp->defdname))
248 				goto freedata;
249 			strcpy(statp->defdname, cp);
250 		}
251 	}
252 #endif	/* SOLARIS2 */
253 
254 	/* Allow user to override the local domain definition */
255 	if (issetugid() == 0 && (cp = getenv("LOCALDOMAIN")) != NULL) {
256 		(void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
257 		statp->defdname[sizeof(statp->defdname) - 1] = '\0';
258 		haveenv++;
259 
260 		/*
261 		 * Set search list to be blank-separated strings
262 		 * from rest of env value.  Permits users of LOCALDOMAIN
263 		 * to still have a search list, and anyone to set the
264 		 * one that they want to use as an individual (even more
265 		 * important now that the rfc1535 stuff restricts searches)
266 		 */
267 		cp = statp->defdname;
268 		pp = statp->dnsrch;
269 		*pp++ = cp;
270 		for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
271 			if (*cp == '\n')	/* silly backwards compat */
272 				break;
273 			else if (*cp == ' ' || *cp == '\t') {
274 				*cp = 0;
275 				n = 1;
276 			} else if (n) {
277 				*pp++ = cp;
278 				n = 0;
279 				havesearch = 1;
280 			}
281 		}
282 		/* null terminate last domain if there are excess */
283 		while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
284 			cp++;
285 		*cp = '\0';
286 		*pp++ = 0;
287 	}
288 
289 #define	MATCH(line, name) \
290 	(!strncmp(line, name, sizeof(name) - 1) && \
291 	(line[sizeof(name) - 1] == ' ' || \
292 	 line[sizeof(name) - 1] == '\t'))
293 
294 	nserv = 0;
295 	if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
296 	    /* read the config file */
297 	    while (fgets(buf, sizeof(buf), fp) != NULL) {
298 		/* skip comments */
299 		if (*buf == ';' || *buf == '#')
300 			continue;
301 		/* read default domain name */
302 		if (MATCH(buf, "domain")) {
303 		    if (haveenv)	/* skip if have from environ */
304 			    continue;
305 		    cp = buf + sizeof("domain") - 1;
306 		    while (*cp == ' ' || *cp == '\t')
307 			    cp++;
308 		    if ((*cp == '\0') || (*cp == '\n'))
309 			    continue;
310 		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
311 		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
312 		    if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
313 			    *cp = '\0';
314 		    havesearch = 0;
315 		    continue;
316 		}
317 		/* set search list */
318 		if (MATCH(buf, "search")) {
319 		    if (haveenv)	/* skip if have from environ */
320 			    continue;
321 		    cp = buf + sizeof("search") - 1;
322 		    while (*cp == ' ' || *cp == '\t')
323 			    cp++;
324 		    if ((*cp == '\0') || (*cp == '\n'))
325 			    continue;
326 		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
327 		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
328 		    if ((cp = strchr(statp->defdname, '\n')) != NULL)
329 			    *cp = '\0';
330 		    /*
331 		     * Set search list to be blank-separated strings
332 		     * on rest of line.
333 		     */
334 		    cp = statp->defdname;
335 		    pp = statp->dnsrch;
336 		    *pp++ = cp;
337 		    for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
338 			    if (*cp == ' ' || *cp == '\t') {
339 				    *cp = 0;
340 				    n = 1;
341 			    } else if (n) {
342 				    *pp++ = cp;
343 				    n = 0;
344 			    }
345 		    }
346 		    /* null terminate last domain if there are excess */
347 		    while (*cp != '\0' && *cp != ' ' && *cp != '\t')
348 			    cp++;
349 		    *cp = '\0';
350 		    *pp++ = 0;
351 		    havesearch = 1;
352 		    continue;
353 		}
354 		/* read nameservers to query */
355 		if (MATCH(buf, "nameserver") && nserv < MAXNS) {
356 		    struct addrinfo hints, *ai;
357 		    char sbuf[NI_MAXSERV];
358 		    const size_t minsiz =
359 		        sizeof(statp->_u._ext.ext->nsaddrs[0]);
360 
361 		    cp = buf + sizeof("nameserver") - 1;
362 		    while (*cp == ' ' || *cp == '\t')
363 			cp++;
364 		    cp[strcspn(cp, ";# \t\n")] = '\0';
365 		    if ((*cp != '\0') && (*cp != '\n')) {
366 			memset(&hints, 0, sizeof(hints));
367 			hints.ai_family = PF_UNSPEC;
368 			hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
369 			hints.ai_flags = AI_NUMERICHOST;
370 			sprintf(sbuf, "%u", NAMESERVER_PORT);
371 			if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
372 			    ai->ai_addrlen <= minsiz) {
373 			    if (statp->_u._ext.ext != NULL) {
374 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
375 				    ai->ai_addr, ai->ai_addrlen);
376 			    }
377 			    if (ai->ai_addrlen <=
378 			        sizeof(statp->nsaddr_list[nserv])) {
379 				memcpy(&statp->nsaddr_list[nserv],
380 				    ai->ai_addr, ai->ai_addrlen);
381 			    } else
382 				statp->nsaddr_list[nserv].sin_family = 0;
383 			    freeaddrinfo(ai);
384 			    nserv++;
385 			}
386 		    }
387 		    continue;
388 		}
389 #ifdef RESOLVSORT
390 		if (MATCH(buf, "sortlist")) {
391 		    struct in_addr a;
392 		    struct in6_addr a6;
393 		    int m, i;
394 		    u_char *u;
395 		    struct __res_state_ext *ext = statp->_u._ext.ext;
396 
397 		    cp = buf + sizeof("sortlist") - 1;
398 		    while (nsort < MAXRESOLVSORT) {
399 			while (*cp == ' ' || *cp == '\t')
400 			    cp++;
401 			if (*cp == '\0' || *cp == '\n' || *cp == ';')
402 			    break;
403 			net = cp;
404 			while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
405 			       isascii(*cp) && !isspace((unsigned char)*cp))
406 				cp++;
407 			n = *cp;
408 			*cp = 0;
409 			if (inet_aton(net, &a)) {
410 			    statp->sort_list[nsort].addr = a;
411 			    if (ISSORTMASK(n)) {
412 				*cp++ = n;
413 				net = cp;
414 				while (*cp && *cp != ';' &&
415 					isascii(*cp) &&
416 					!isspace((unsigned char)*cp))
417 				    cp++;
418 				n = *cp;
419 				*cp = 0;
420 				if (inet_aton(net, &a)) {
421 				    statp->sort_list[nsort].mask = a.s_addr;
422 				} else {
423 				    statp->sort_list[nsort].mask =
424 					net_mask(statp->sort_list[nsort].addr);
425 				}
426 			    } else {
427 				statp->sort_list[nsort].mask =
428 				    net_mask(statp->sort_list[nsort].addr);
429 			    }
430 			    ext->sort_list[nsort].af = AF_INET;
431 			    ext->sort_list[nsort].addr.ina =
432 				statp->sort_list[nsort].addr;
433 			    ext->sort_list[nsort].mask.ina.s_addr =
434 				statp->sort_list[nsort].mask;
435 			    nsort++;
436 			}
437 			else if (inet_pton(AF_INET6, net, &a6) == 1) {
438 
439 			    ext->sort_list[nsort].af = AF_INET6;
440 			    ext->sort_list[nsort].addr.in6a = a6;
441 			    u = (u_char *)&ext->sort_list[nsort].mask.in6a;
442 			    *cp++ = n;
443 			    net = cp;
444 			    while (*cp && *cp != ';' &&
445 				    isascii(*cp) && !isspace(*cp))
446 				cp++;
447 			    m = n;
448 			    n = *cp;
449 			    *cp = 0;
450 			    switch (m) {
451 			    case '/':
452 				m = atoi(net);
453 				break;
454 			    case '&':
455 				if (inet_pton(AF_INET6, net, u) == 1) {
456 				    m = -1;
457 				    break;
458 				}
459 				/*FALLTHROUGH*/
460 			    default:
461 				m = sizeof(struct in6_addr) * CHAR_BIT;
462 				break;
463 			    }
464 			    if (m >= 0) {
465 				for (i = 0; i < sizeof(struct in6_addr); i++) {
466 				    if (m <= 0) {
467 					*u = 0;
468 				    } else {
469 					m -= CHAR_BIT;
470 					*u = (u_char)~0;
471 					if (m < 0)
472 					    *u <<= -m;
473 				    }
474 				    u++;
475 				}
476 			    }
477 			    statp->sort_list[nsort].addr.s_addr =
478 				(u_int32_t)0xffffffff;
479 			    statp->sort_list[nsort].mask =
480 				(u_int32_t)0xffffffff;
481 			    nsort++;
482 			}
483 			*cp = n;
484 		    }
485 		    continue;
486 		}
487 #endif
488 		if (MATCH(buf, "options")) {
489 		    res_setoptions(statp, buf + sizeof("options") - 1, "conf");
490 		    continue;
491 		}
492 	    }
493 	    if (nserv > 0)
494 		statp->nscount = nserv;
495 #ifdef RESOLVSORT
496 	    statp->nsort = nsort;
497 #endif
498 	    (void) fclose(fp);
499 	}
500 /*
501  * Last chance to get a nameserver.  This should not normally
502  * be necessary
503  */
504 #ifdef NO_RESOLV_CONF
505 	if(nserv == 0)
506 		nserv = get_nameservers(statp);
507 #endif
508 
509 	if (statp->defdname[0] == 0 &&
510 	    gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
511 	    (cp = strchr(buf, '.')) != NULL)
512 		strcpy(statp->defdname, cp + 1);
513 
514 	/* find components of local domain that might be searched */
515 	if (havesearch == 0) {
516 		pp = statp->dnsrch;
517 		*pp++ = statp->defdname;
518 		*pp = NULL;
519 
520 		dots = 0;
521 		for (cp = statp->defdname; *cp; cp++)
522 			dots += (*cp == '.');
523 
524 		cp = statp->defdname;
525 		while (pp < statp->dnsrch + MAXDFLSRCH) {
526 			if (dots < LOCALDOMAINPARTS)
527 				break;
528 			cp = strchr(cp, '.') + 1;    /* we know there is one */
529 			*pp++ = cp;
530 			dots--;
531 		}
532 		*pp = NULL;
533 #ifdef DEBUG
534 		if (statp->options & RES_DEBUG) {
535 			printf(";; res_init()... default dnsrch list:\n");
536 			for (pp = statp->dnsrch; *pp; pp++)
537 				printf(";;\t%s\n", *pp);
538 			printf(";;\t..END..\n");
539 		}
540 #endif
541 	}
542 
543 	if (issetugid())
544 		statp->options |= RES_NOALIASES;
545 	else if ((cp = getenv("RES_OPTIONS")) != NULL)
546 		res_setoptions(statp, cp, "env");
547 	statp->options |= RES_INIT;
548 	return (0);
549 
550 #ifdef	SOLARIS2
551  freedata:
552 	if (statp->_u._ext.ext != NULL) {
553 		free(statp->_u._ext.ext);
554 		statp->_u._ext.ext = NULL;
555 	}
556 	return (-1);
557 #endif
558 }
559 
560 static void
561 res_setoptions(res_state statp, const char *options, const char *source)
562 {
563 	const char *cp = options;
564 	int i;
565 #ifndef _LIBC
566 	struct __res_state_ext *ext = statp->_u._ext.ext;
567 #endif
568 
569 #ifdef DEBUG
570 	if (statp->options & RES_DEBUG)
571 		printf(";; res_setoptions(\"%s\", \"%s\")...\n",
572 		       options, source);
573 #endif
574 	while (*cp) {
575 		/* skip leading and inner runs of spaces */
576 		while (*cp == ' ' || *cp == '\t')
577 			cp++;
578 		/* search for and process individual options */
579 		if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
580 			i = atoi(cp + sizeof("ndots:") - 1);
581 			if (i <= RES_MAXNDOTS)
582 				statp->ndots = i;
583 			else
584 				statp->ndots = RES_MAXNDOTS;
585 #ifdef DEBUG
586 			if (statp->options & RES_DEBUG)
587 				printf(";;\tndots=%d\n", statp->ndots);
588 #endif
589 		} else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
590 			i = atoi(cp + sizeof("timeout:") - 1);
591 			if (i <= RES_MAXRETRANS)
592 				statp->retrans = i;
593 			else
594 				statp->retrans = RES_MAXRETRANS;
595 #ifdef DEBUG
596 			if (statp->options & RES_DEBUG)
597 				printf(";;\ttimeout=%d\n", statp->retrans);
598 #endif
599 #ifdef	SOLARIS2
600 		} else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) {
601 			/*
602 		 	 * For backward compatibility, 'retrans' is
603 		 	 * supported as an alias for 'timeout', though
604 		 	 * without an imposed maximum.
605 		 	 */
606 			statp->retrans = atoi(cp + sizeof("retrans:") - 1);
607 		} else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){
608 			/*
609 			 * For backward compatibility, 'retry' is
610 			 * supported as an alias for 'attempts', though
611 			 * without an imposed maximum.
612 			 */
613 			statp->retry = atoi(cp + sizeof("retry:") - 1);
614 #endif	/* SOLARIS2 */
615 		} else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
616 			i = atoi(cp + sizeof("attempts:") - 1);
617 			if (i <= RES_MAXRETRY)
618 				statp->retry = i;
619 			else
620 				statp->retry = RES_MAXRETRY;
621 #ifdef DEBUG
622 			if (statp->options & RES_DEBUG)
623 				printf(";;\tattempts=%d\n", statp->retry);
624 #endif
625 		} else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
626 #ifdef DEBUG
627 			if (!(statp->options & RES_DEBUG)) {
628 				printf(";; res_setoptions(\"%s\", \"%s\")..\n",
629 				       options, source);
630 				statp->options |= RES_DEBUG;
631 			}
632 			printf(";;\tdebug\n");
633 #endif
634 		} else if (!strncmp(cp, "no_tld_query",
635 				    sizeof("no_tld_query") - 1) ||
636 			   !strncmp(cp, "no-tld-query",
637 				    sizeof("no-tld-query") - 1)) {
638 			statp->options |= RES_NOTLDQUERY;
639 		} else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
640 			statp->options |= RES_USE_INET6;
641 		} else if (!strncmp(cp, "insecure1", sizeof("insecure1") - 1)) {
642 		       statp->options |= RES_INSECURE1;
643 		} else if (!strncmp(cp, "insecure2", sizeof("insecure2") - 1)) {
644 		       statp->options |= RES_INSECURE2;
645 		} else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
646 			statp->options |= RES_ROTATE;
647 		} else if (!strncmp(cp, "no-check-names",
648 				    sizeof("no-check-names") - 1)) {
649 			statp->options |= RES_NOCHECKNAME;
650 		}
651 #ifdef RES_USE_EDNS0
652 		else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
653 			statp->options |= RES_USE_EDNS0;
654 		}
655 #endif
656 #ifndef _LIBC
657 		else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
658 			statp->options |= RES_USE_DNAME;
659 		}
660 		else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
661 			if (ext == NULL)
662 				goto skip;
663 			cp += sizeof("nibble:") - 1;
664 			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
665 			strncpy(ext->nsuffix, cp, i);
666 			ext->nsuffix[i] = '\0';
667 		}
668 		else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
669 			if (ext == NULL)
670 				goto skip;
671 			cp += sizeof("nibble2:") - 1;
672 			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
673 			strncpy(ext->nsuffix2, cp, i);
674 			ext->nsuffix2[i] = '\0';
675 		}
676 		else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
677 			cp += sizeof("v6revmode:") - 1;
678 			/* "nibble" and "bitstring" used to be valid */
679 			if (!strncmp(cp, "single", sizeof("single") - 1)) {
680 				statp->options |= RES_NO_NIBBLE2;
681 			} else if (!strncmp(cp, "both", sizeof("both") - 1)) {
682 				statp->options &=
683 					 ~RES_NO_NIBBLE2;
684 			}
685 		}
686 #endif
687 		else {
688 			/* XXX - print a warning here? */
689 		}
690 #ifndef _LIBC
691    skip:
692 #endif
693 		/* skip to next run of spaces */
694 		while (*cp && *cp != ' ' && *cp != '\t')
695 			cp++;
696 	}
697 }
698 
699 #ifdef RESOLVSORT
700 /* XXX - should really support CIDR which means explicit masks always. */
701 static u_int32_t
702 net_mask(in)		/* XXX - should really use system's version of this */
703 	struct in_addr in;
704 {
705 	u_int32_t i = ntohl(in.s_addr);
706 
707 	if (IN_CLASSA(i))
708 		return (htonl(IN_CLASSA_NET));
709 	else if (IN_CLASSB(i))
710 		return (htonl(IN_CLASSB_NET));
711 	return (htonl(IN_CLASSC_NET));
712 }
713 #endif
714 
715 u_int
716 res_randomid(void) {
717 	struct timeval now;
718 
719 	gettimeofday(&now, NULL);
720 	return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));
721 }
722 
723 /*
724  * This routine is for closing the socket if a virtual circuit is used and
725  * the program wants to close it.  This provides support for endhostent()
726  * which expects to close the socket.
727  *
728  * This routine is not expected to be user visible.
729  */
730 void
731 res_nclose(res_state statp) {
732 	int ns;
733 
734 	if (statp->_vcsock >= 0) {
735 		(void) _close(statp->_vcsock);
736 		statp->_vcsock = -1;
737 		statp->_flags &= ~(RES_F_VC | RES_F_CONN);
738 	}
739 	for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
740 		if (statp->_u._ext.nssocks[ns] != -1) {
741 			(void) _close(statp->_u._ext.nssocks[ns]);
742 			statp->_u._ext.nssocks[ns] = -1;
743 		}
744 	}
745 }
746 
747 void
748 res_ndestroy(res_state statp) {
749 	res_nclose(statp);
750 	if (statp->_u._ext.ext != NULL)
751 		free(statp->_u._ext.ext);
752 	statp->options &= ~RES_INIT;
753 	statp->_u._ext.ext = NULL;
754 }
755 
756 #ifndef _LIBC
757 const char *
758 res_get_nibblesuffix(res_state statp) {
759 	if (statp->_u._ext.ext)
760 		return (statp->_u._ext.ext->nsuffix);
761 	return ("ip6.arpa");
762 }
763 
764 const char *
765 res_get_nibblesuffix2(res_state statp) {
766 	if (statp->_u._ext.ext)
767 		return (statp->_u._ext.ext->nsuffix2);
768 	return ("ip6.int");
769 }
770 #endif
771 
772 void
773 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
774 	int i, nserv;
775 	size_t size;
776 
777 	/* close open servers */
778 	res_nclose(statp);
779 
780 	/* cause rtt times to be forgotten */
781 	statp->_u._ext.nscount = 0;
782 
783 	nserv = 0;
784 	for (i = 0; i < cnt && nserv < MAXNS; i++) {
785 		switch (set->sin.sin_family) {
786 		case AF_INET:
787 			size = sizeof(set->sin);
788 			if (statp->_u._ext.ext)
789 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
790 					&set->sin, size);
791 			if (size <= sizeof(statp->nsaddr_list[nserv]))
792 				memcpy(&statp->nsaddr_list[nserv],
793 					&set->sin, size);
794 			else
795 				statp->nsaddr_list[nserv].sin_family = 0;
796 			nserv++;
797 			break;
798 
799 #ifdef HAS_INET6_STRUCTS
800 		case AF_INET6:
801 			size = sizeof(set->sin6);
802 			if (statp->_u._ext.ext)
803 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
804 					&set->sin6, size);
805 			if (size <= sizeof(statp->nsaddr_list[nserv]))
806 				memcpy(&statp->nsaddr_list[nserv],
807 					&set->sin6, size);
808 			else
809 				statp->nsaddr_list[nserv].sin_family = 0;
810 			nserv++;
811 			break;
812 #endif
813 
814 		default:
815 			break;
816 		}
817 		set++;
818 	}
819 	statp->nscount = nserv;
820 
821 }
822 
823 int
824 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
825 	int i;
826 	size_t size;
827 	u_int16_t family;
828 
829 	for (i = 0; i < statp->nscount && i < cnt; i++) {
830 		if (statp->_u._ext.ext)
831 			family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
832 		else
833 			family = statp->nsaddr_list[i].sin_family;
834 
835 		switch (family) {
836 		case AF_INET:
837 			size = sizeof(set->sin);
838 			if (statp->_u._ext.ext)
839 				memcpy(&set->sin,
840 				       &statp->_u._ext.ext->nsaddrs[i],
841 				       size);
842 			else
843 				memcpy(&set->sin, &statp->nsaddr_list[i],
844 				       size);
845 			break;
846 
847 #ifdef HAS_INET6_STRUCTS
848 		case AF_INET6:
849 			size = sizeof(set->sin6);
850 			if (statp->_u._ext.ext)
851 				memcpy(&set->sin6,
852 				       &statp->_u._ext.ext->nsaddrs[i],
853 				       size);
854 			else
855 				memcpy(&set->sin6, &statp->nsaddr_list[i],
856 				       size);
857 			break;
858 #endif
859 
860 		default:
861 			set->sin.sin_family = 0;
862 			break;
863 		}
864 		set++;
865 	}
866 	return (statp->nscount);
867 }
868