xref: /freebsd/lib/libc/resolv/res_init.c (revision 3c6e15bceeab4470243c60c9a4b5b9cafca9abaa)
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 1.16.18.7 2007/07/09 01:52:58 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 	int maxns = MAXNS;
172 
173 	RES_SET_H_ERRNO(statp, 0);
174 	if (statp->_u._ext.ext != NULL)
175 		res_ndestroy(statp);
176 
177 	if (!preinit) {
178 		statp->retrans = RES_TIMEOUT;
179 		statp->retry = RES_DFLRETRY;
180 		statp->options = RES_DEFAULT;
181 		statp->id = res_randomid();
182 	}
183 
184 	memset(u, 0, sizeof(u));
185 #ifdef USELOOPBACK
186 	u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
187 #else
188 	u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
189 #endif
190 	u[nserv].sin.sin_family = AF_INET;
191 	u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
192 #ifdef HAVE_SA_LEN
193 	u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
194 #endif
195 	nserv++;
196 #ifdef HAS_INET6_STRUCTS
197 #ifdef USELOOPBACK
198 	u[nserv].sin6.sin6_addr = in6addr_loopback;
199 #else
200 	u[nserv].sin6.sin6_addr = in6addr_any;
201 #endif
202 	u[nserv].sin6.sin6_family = AF_INET6;
203 	u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
204 #ifdef HAVE_SA_LEN
205 	u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
206 #endif
207 	nserv++;
208 #endif
209 	statp->nscount = 0;
210 	statp->ndots = 1;
211 	statp->pfcode = 0;
212 	statp->_vcsock = -1;
213 	statp->_flags = 0;
214 	statp->qhook = NULL;
215 	statp->rhook = NULL;
216 	statp->_u._ext.nscount = 0;
217 	statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
218 	if (statp->_u._ext.ext != NULL) {
219 	        memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
220 		statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
221 		strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
222 		strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
223 	} else {
224 		/*
225 		 * Historically res_init() rarely, if at all, failed.
226 		 * Examples and applications exist which do not check
227 		 * our return code.  Furthermore several applications
228 		 * simply call us to get the systems domainname.  So
229 		 * rather then immediately fail here we store the
230 		 * failure, which is returned later, in h_errno.  And
231 		 * prevent the collection of 'nameserver' information
232 		 * by setting maxns to 0.  Thus applications that fail
233 		 * to check our return code wont be able to make
234 		 * queries anyhow.
235 		 */
236 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
237 		maxns = 0;
238 	}
239 #ifdef RESOLVSORT
240 	statp->nsort = 0;
241 #endif
242 	res_setservers(statp, u, nserv);
243 
244 #ifdef	SOLARIS2
245 	/*
246 	 * The old libresolv derived the defaultdomain from NIS/NIS+.
247 	 * We want to keep this behaviour
248 	 */
249 	{
250 		char buf[sizeof(statp->defdname)], *cp;
251 		int ret;
252 
253 		if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 &&
254 			(unsigned int)ret <= sizeof(buf)) {
255 			if (buf[0] == '+')
256 				buf[0] = '.';
257 			cp = strchr(buf, '.');
258 			cp = (cp == NULL) ? buf : (cp + 1);
259 			strncpy(statp->defdname, cp,
260 				sizeof(statp->defdname) - 1);
261 			statp->defdname[sizeof(statp->defdname) - 1] = '\0';
262 		}
263 	}
264 #endif	/* SOLARIS2 */
265 
266 	/* Allow user to override the local domain definition */
267 	if (issetugid() == 0 && (cp = getenv("LOCALDOMAIN")) != NULL) {
268 		(void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
269 		statp->defdname[sizeof(statp->defdname) - 1] = '\0';
270 		haveenv++;
271 
272 		/*
273 		 * Set search list to be blank-separated strings
274 		 * from rest of env value.  Permits users of LOCALDOMAIN
275 		 * to still have a search list, and anyone to set the
276 		 * one that they want to use as an individual (even more
277 		 * important now that the rfc1535 stuff restricts searches)
278 		 */
279 		cp = statp->defdname;
280 		pp = statp->dnsrch;
281 		*pp++ = cp;
282 		for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
283 			if (*cp == '\n')	/*%< silly backwards compat */
284 				break;
285 			else if (*cp == ' ' || *cp == '\t') {
286 				*cp = 0;
287 				n = 1;
288 			} else if (n) {
289 				*pp++ = cp;
290 				n = 0;
291 				havesearch = 1;
292 			}
293 		}
294 		/* null terminate last domain if there are excess */
295 		while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
296 			cp++;
297 		*cp = '\0';
298 		*pp++ = 0;
299 	}
300 
301 #define	MATCH(line, name) \
302 	(!strncmp(line, name, sizeof(name) - 1) && \
303 	(line[sizeof(name) - 1] == ' ' || \
304 	 line[sizeof(name) - 1] == '\t'))
305 
306 	nserv = 0;
307 	if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
308 	    /* read the config file */
309 	    while (fgets(buf, sizeof(buf), fp) != NULL) {
310 		/* skip comments */
311 		if (*buf == ';' || *buf == '#')
312 			continue;
313 		/* read default domain name */
314 		if (MATCH(buf, "domain")) {
315 		    if (haveenv)	/*%< skip if have from environ */
316 			    continue;
317 		    cp = buf + sizeof("domain") - 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 = strpbrk(statp->defdname, " \t\n")) != NULL)
325 			    *cp = '\0';
326 		    havesearch = 0;
327 		    continue;
328 		}
329 		/* set search list */
330 		if (MATCH(buf, "search")) {
331 		    if (haveenv)	/*%< skip if have from environ */
332 			    continue;
333 		    cp = buf + sizeof("search") - 1;
334 		    while (*cp == ' ' || *cp == '\t')
335 			    cp++;
336 		    if ((*cp == '\0') || (*cp == '\n'))
337 			    continue;
338 		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
339 		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
340 		    if ((cp = strchr(statp->defdname, '\n')) != NULL)
341 			    *cp = '\0';
342 		    /*
343 		     * Set search list to be blank-separated strings
344 		     * on rest of line.
345 		     */
346 		    cp = statp->defdname;
347 		    pp = statp->dnsrch;
348 		    *pp++ = cp;
349 		    for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
350 			    if (*cp == ' ' || *cp == '\t') {
351 				    *cp = 0;
352 				    n = 1;
353 			    } else if (n) {
354 				    *pp++ = cp;
355 				    n = 0;
356 			    }
357 		    }
358 		    /* null terminate last domain if there are excess */
359 		    while (*cp != '\0' && *cp != ' ' && *cp != '\t')
360 			    cp++;
361 		    *cp = '\0';
362 		    *pp++ = 0;
363 		    havesearch = 1;
364 		    continue;
365 		}
366 		/* read nameservers to query */
367 		if (MATCH(buf, "nameserver") && nserv < maxns) {
368 		    struct addrinfo hints, *ai;
369 		    char sbuf[NI_MAXSERV];
370 		    const size_t minsiz =
371 		        sizeof(statp->_u._ext.ext->nsaddrs[0]);
372 
373 		    cp = buf + sizeof("nameserver") - 1;
374 		    while (*cp == ' ' || *cp == '\t')
375 			cp++;
376 		    cp[strcspn(cp, ";# \t\n")] = '\0';
377 		    if ((*cp != '\0') && (*cp != '\n')) {
378 			memset(&hints, 0, sizeof(hints));
379 			hints.ai_family = PF_UNSPEC;
380 			hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
381 			hints.ai_flags = AI_NUMERICHOST;
382 			sprintf(sbuf, "%u", NAMESERVER_PORT);
383 			if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
384 			    ai->ai_addrlen <= minsiz) {
385 			    if (statp->_u._ext.ext != NULL) {
386 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
387 				    ai->ai_addr, ai->ai_addrlen);
388 			    }
389 			    if (ai->ai_addrlen <=
390 			        sizeof(statp->nsaddr_list[nserv])) {
391 				memcpy(&statp->nsaddr_list[nserv],
392 				    ai->ai_addr, ai->ai_addrlen);
393 			    } else
394 				statp->nsaddr_list[nserv].sin_family = 0;
395 			    freeaddrinfo(ai);
396 			    nserv++;
397 			}
398 		    }
399 		    continue;
400 		}
401 #ifdef RESOLVSORT
402 		if (MATCH(buf, "sortlist")) {
403 		    struct in_addr a;
404 		    struct in6_addr a6;
405 		    int m, i;
406 		    u_char *u;
407 		    struct __res_state_ext *ext = statp->_u._ext.ext;
408 
409 		    cp = buf + sizeof("sortlist") - 1;
410 		    while (nsort < MAXRESOLVSORT) {
411 			while (*cp == ' ' || *cp == '\t')
412 			    cp++;
413 			if (*cp == '\0' || *cp == '\n' || *cp == ';')
414 			    break;
415 			net = cp;
416 			while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
417 			       isascii(*cp) && !isspace((unsigned char)*cp))
418 				cp++;
419 			n = *cp;
420 			*cp = 0;
421 			if (inet_aton(net, &a)) {
422 			    statp->sort_list[nsort].addr = a;
423 			    if (ISSORTMASK(n)) {
424 				*cp++ = n;
425 				net = cp;
426 				while (*cp && *cp != ';' &&
427 					isascii(*cp) &&
428 					!isspace((unsigned char)*cp))
429 				    cp++;
430 				n = *cp;
431 				*cp = 0;
432 				if (inet_aton(net, &a)) {
433 				    statp->sort_list[nsort].mask = a.s_addr;
434 				} else {
435 				    statp->sort_list[nsort].mask =
436 					net_mask(statp->sort_list[nsort].addr);
437 				}
438 			    } else {
439 				statp->sort_list[nsort].mask =
440 				    net_mask(statp->sort_list[nsort].addr);
441 			    }
442 			    ext->sort_list[nsort].af = AF_INET;
443 			    ext->sort_list[nsort].addr.ina =
444 				statp->sort_list[nsort].addr;
445 			    ext->sort_list[nsort].mask.ina.s_addr =
446 				statp->sort_list[nsort].mask;
447 			    nsort++;
448 			}
449 			else if (inet_pton(AF_INET6, net, &a6) == 1) {
450 
451 			    ext->sort_list[nsort].af = AF_INET6;
452 			    ext->sort_list[nsort].addr.in6a = a6;
453 			    u = (u_char *)&ext->sort_list[nsort].mask.in6a;
454 			    *cp++ = n;
455 			    net = cp;
456 			    while (*cp && *cp != ';' &&
457 				    isascii(*cp) && !isspace(*cp))
458 				cp++;
459 			    m = n;
460 			    n = *cp;
461 			    *cp = 0;
462 			    switch (m) {
463 			    case '/':
464 				m = atoi(net);
465 				break;
466 			    case '&':
467 				if (inet_pton(AF_INET6, net, u) == 1) {
468 				    m = -1;
469 				    break;
470 				}
471 				/*FALLTHROUGH*/
472 			    default:
473 				m = sizeof(struct in6_addr) * CHAR_BIT;
474 				break;
475 			    }
476 			    if (m >= 0) {
477 				for (i = 0; i < sizeof(struct in6_addr); i++) {
478 				    if (m <= 0) {
479 					*u = 0;
480 				    } else {
481 					m -= CHAR_BIT;
482 					*u = (u_char)~0;
483 					if (m < 0)
484 					    *u <<= -m;
485 				    }
486 				    u++;
487 				}
488 			    }
489 			    statp->sort_list[nsort].addr.s_addr =
490 				(u_int32_t)0xffffffff;
491 			    statp->sort_list[nsort].mask =
492 				(u_int32_t)0xffffffff;
493 			    nsort++;
494 			}
495 			*cp = n;
496 		    }
497 		    continue;
498 		}
499 #endif
500 		if (MATCH(buf, "options")) {
501 		    res_setoptions(statp, buf + sizeof("options") - 1, "conf");
502 		    continue;
503 		}
504 	    }
505 	    if (nserv > 0)
506 		statp->nscount = nserv;
507 #ifdef RESOLVSORT
508 	    statp->nsort = nsort;
509 #endif
510 	    (void) fclose(fp);
511 	}
512 /*
513  * Last chance to get a nameserver.  This should not normally
514  * be necessary
515  */
516 #ifdef NO_RESOLV_CONF
517 	if(nserv == 0)
518 		nserv = get_nameservers(statp);
519 #endif
520 
521 	if (statp->defdname[0] == 0 &&
522 	    gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
523 	    (cp = strchr(buf, '.')) != NULL)
524 		strcpy(statp->defdname, cp + 1);
525 
526 	/* find components of local domain that might be searched */
527 	if (havesearch == 0) {
528 		pp = statp->dnsrch;
529 		*pp++ = statp->defdname;
530 		*pp = NULL;
531 
532 		dots = 0;
533 		for (cp = statp->defdname; *cp; cp++)
534 			dots += (*cp == '.');
535 
536 		cp = statp->defdname;
537 		while (pp < statp->dnsrch + MAXDFLSRCH) {
538 			if (dots < LOCALDOMAINPARTS)
539 				break;
540 			cp = strchr(cp, '.') + 1;    /*%< we know there is one */
541 			*pp++ = cp;
542 			dots--;
543 		}
544 		*pp = NULL;
545 #ifdef DEBUG
546 		if (statp->options & RES_DEBUG) {
547 			printf(";; res_init()... default dnsrch list:\n");
548 			for (pp = statp->dnsrch; *pp; pp++)
549 				printf(";;\t%s\n", *pp);
550 			printf(";;\t..END..\n");
551 		}
552 #endif
553 	}
554 
555 	if (issetugid())
556 		statp->options |= RES_NOALIASES;
557 	else if ((cp = getenv("RES_OPTIONS")) != NULL)
558 		res_setoptions(statp, cp, "env");
559 	statp->options |= RES_INIT;
560 	return (statp->res_h_errno);
561 }
562 
563 static void
564 res_setoptions(res_state statp, const char *options, const char *source)
565 {
566 	const char *cp = options;
567 	int i;
568 #ifndef _LIBC
569 	struct __res_state_ext *ext = statp->_u._ext.ext;
570 #endif
571 
572 #ifdef DEBUG
573 	if (statp->options & RES_DEBUG)
574 		printf(";; res_setoptions(\"%s\", \"%s\")...\n",
575 		       options, source);
576 #endif
577 	while (*cp) {
578 		/* skip leading and inner runs of spaces */
579 		while (*cp == ' ' || *cp == '\t')
580 			cp++;
581 		/* search for and process individual options */
582 		if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
583 			i = atoi(cp + sizeof("ndots:") - 1);
584 			if (i <= RES_MAXNDOTS)
585 				statp->ndots = i;
586 			else
587 				statp->ndots = RES_MAXNDOTS;
588 #ifdef DEBUG
589 			if (statp->options & RES_DEBUG)
590 				printf(";;\tndots=%d\n", statp->ndots);
591 #endif
592 		} else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
593 			i = atoi(cp + sizeof("timeout:") - 1);
594 			if (i <= RES_MAXRETRANS)
595 				statp->retrans = i;
596 			else
597 				statp->retrans = RES_MAXRETRANS;
598 #ifdef DEBUG
599 			if (statp->options & RES_DEBUG)
600 				printf(";;\ttimeout=%d\n", statp->retrans);
601 #endif
602 #ifdef	SOLARIS2
603 		} else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) {
604 			/*
605 		 	 * For backward compatibility, 'retrans' is
606 		 	 * supported as an alias for 'timeout', though
607 		 	 * without an imposed maximum.
608 		 	 */
609 			statp->retrans = atoi(cp + sizeof("retrans:") - 1);
610 		} else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){
611 			/*
612 			 * For backward compatibility, 'retry' is
613 			 * supported as an alias for 'attempts', though
614 			 * without an imposed maximum.
615 			 */
616 			statp->retry = atoi(cp + sizeof("retry:") - 1);
617 #endif	/* SOLARIS2 */
618 		} else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
619 			i = atoi(cp + sizeof("attempts:") - 1);
620 			if (i <= RES_MAXRETRY)
621 				statp->retry = i;
622 			else
623 				statp->retry = RES_MAXRETRY;
624 #ifdef DEBUG
625 			if (statp->options & RES_DEBUG)
626 				printf(";;\tattempts=%d\n", statp->retry);
627 #endif
628 		} else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
629 #ifdef DEBUG
630 			if (!(statp->options & RES_DEBUG)) {
631 				printf(";; res_setoptions(\"%s\", \"%s\")..\n",
632 				       options, source);
633 				statp->options |= RES_DEBUG;
634 			}
635 			printf(";;\tdebug\n");
636 #endif
637 		} else if (!strncmp(cp, "no_tld_query",
638 				    sizeof("no_tld_query") - 1) ||
639 			   !strncmp(cp, "no-tld-query",
640 				    sizeof("no-tld-query") - 1)) {
641 			statp->options |= RES_NOTLDQUERY;
642 		} else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
643 			statp->options |= RES_USE_INET6;
644 		} else if (!strncmp(cp, "insecure1", sizeof("insecure1") - 1)) {
645 		       statp->options |= RES_INSECURE1;
646 		} else if (!strncmp(cp, "insecure2", sizeof("insecure2") - 1)) {
647 		       statp->options |= RES_INSECURE2;
648 		} else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
649 			statp->options |= RES_ROTATE;
650 		} else if (!strncmp(cp, "no-check-names",
651 				    sizeof("no-check-names") - 1)) {
652 			statp->options |= RES_NOCHECKNAME;
653 		}
654 #ifdef RES_USE_EDNS0
655 		else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
656 			statp->options |= RES_USE_EDNS0;
657 		}
658 #endif
659 #ifndef _LIBC
660 		else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
661 			statp->options |= RES_USE_DNAME;
662 		}
663 		else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
664 			if (ext == NULL)
665 				goto skip;
666 			cp += sizeof("nibble:") - 1;
667 			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
668 			strncpy(ext->nsuffix, cp, i);
669 			ext->nsuffix[i] = '\0';
670 		}
671 		else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
672 			if (ext == NULL)
673 				goto skip;
674 			cp += sizeof("nibble2:") - 1;
675 			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
676 			strncpy(ext->nsuffix2, cp, i);
677 			ext->nsuffix2[i] = '\0';
678 		}
679 		else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
680 			cp += sizeof("v6revmode:") - 1;
681 			/* "nibble" and "bitstring" used to be valid */
682 			if (!strncmp(cp, "single", sizeof("single") - 1)) {
683 				statp->options |= RES_NO_NIBBLE2;
684 			} else if (!strncmp(cp, "both", sizeof("both") - 1)) {
685 				statp->options &=
686 					 ~RES_NO_NIBBLE2;
687 			}
688 		}
689 #endif
690 		else {
691 			/* XXX - print a warning here? */
692 		}
693 #ifndef _LIBC
694    skip:
695 #endif
696 		/* skip to next run of spaces */
697 		while (*cp && *cp != ' ' && *cp != '\t')
698 			cp++;
699 	}
700 }
701 
702 #ifdef RESOLVSORT
703 /* XXX - should really support CIDR which means explicit masks always. */
704 static u_int32_t
705 net_mask(in)		/*!< XXX - should really use system's version of this  */
706 	struct in_addr in;
707 {
708 	u_int32_t i = ntohl(in.s_addr);
709 
710 	if (IN_CLASSA(i))
711 		return (htonl(IN_CLASSA_NET));
712 	else if (IN_CLASSB(i))
713 		return (htonl(IN_CLASSB_NET));
714 	return (htonl(IN_CLASSC_NET));
715 }
716 #endif
717 
718 u_int
719 res_randomid(void) {
720 	struct timeval now;
721 
722 	gettimeofday(&now, NULL);
723 	return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));
724 }
725 
726 /*%
727  * This routine is for closing the socket if a virtual circuit is used and
728  * the program wants to close it.  This provides support for endhostent()
729  * which expects to close the socket.
730  *
731  * This routine is not expected to be user visible.
732  */
733 void
734 res_nclose(res_state statp) {
735 	int ns;
736 
737 	if (statp->_vcsock >= 0) {
738 		(void) _close(statp->_vcsock);
739 		statp->_vcsock = -1;
740 		statp->_flags &= ~(RES_F_VC | RES_F_CONN);
741 	}
742 	for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
743 		if (statp->_u._ext.nssocks[ns] != -1) {
744 			(void) _close(statp->_u._ext.nssocks[ns]);
745 			statp->_u._ext.nssocks[ns] = -1;
746 		}
747 	}
748 }
749 
750 void
751 res_ndestroy(res_state statp) {
752 	res_nclose(statp);
753 	if (statp->_u._ext.ext != NULL)
754 		free(statp->_u._ext.ext);
755 	statp->options &= ~RES_INIT;
756 	statp->_u._ext.ext = NULL;
757 }
758 
759 #ifndef _LIBC
760 const char *
761 res_get_nibblesuffix(res_state statp) {
762 	if (statp->_u._ext.ext)
763 		return (statp->_u._ext.ext->nsuffix);
764 	return ("ip6.arpa");
765 }
766 
767 const char *
768 res_get_nibblesuffix2(res_state statp) {
769 	if (statp->_u._ext.ext)
770 		return (statp->_u._ext.ext->nsuffix2);
771 	return ("ip6.int");
772 }
773 #endif
774 
775 void
776 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
777 	int i, nserv;
778 	size_t size;
779 
780 	/* close open servers */
781 	res_nclose(statp);
782 
783 	/* cause rtt times to be forgotten */
784 	statp->_u._ext.nscount = 0;
785 
786 	nserv = 0;
787 	for (i = 0; i < cnt && nserv < MAXNS; i++) {
788 		switch (set->sin.sin_family) {
789 		case AF_INET:
790 			size = sizeof(set->sin);
791 			if (statp->_u._ext.ext)
792 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
793 					&set->sin, size);
794 			if (size <= sizeof(statp->nsaddr_list[nserv]))
795 				memcpy(&statp->nsaddr_list[nserv],
796 					&set->sin, size);
797 			else
798 				statp->nsaddr_list[nserv].sin_family = 0;
799 			nserv++;
800 			break;
801 
802 #ifdef HAS_INET6_STRUCTS
803 		case AF_INET6:
804 			size = sizeof(set->sin6);
805 			if (statp->_u._ext.ext)
806 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
807 					&set->sin6, size);
808 			if (size <= sizeof(statp->nsaddr_list[nserv]))
809 				memcpy(&statp->nsaddr_list[nserv],
810 					&set->sin6, size);
811 			else
812 				statp->nsaddr_list[nserv].sin_family = 0;
813 			nserv++;
814 			break;
815 #endif
816 
817 		default:
818 			break;
819 		}
820 		set++;
821 	}
822 	statp->nscount = nserv;
823 
824 }
825 
826 int
827 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
828 	int i;
829 	size_t size;
830 	u_int16_t family;
831 
832 	for (i = 0; i < statp->nscount && i < cnt; i++) {
833 		if (statp->_u._ext.ext)
834 			family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
835 		else
836 			family = statp->nsaddr_list[i].sin_family;
837 
838 		switch (family) {
839 		case AF_INET:
840 			size = sizeof(set->sin);
841 			if (statp->_u._ext.ext)
842 				memcpy(&set->sin,
843 				       &statp->_u._ext.ext->nsaddrs[i],
844 				       size);
845 			else
846 				memcpy(&set->sin, &statp->nsaddr_list[i],
847 				       size);
848 			break;
849 
850 #ifdef HAS_INET6_STRUCTS
851 		case AF_INET6:
852 			size = sizeof(set->sin6);
853 			if (statp->_u._ext.ext)
854 				memcpy(&set->sin6,
855 				       &statp->_u._ext.ext->nsaddrs[i],
856 				       size);
857 			else
858 				memcpy(&set->sin6, &statp->nsaddr_list[i],
859 				       size);
860 			break;
861 #endif
862 
863 		default:
864 			set->sin.sin_family = 0;
865 			break;
866 		}
867 		set++;
868 	}
869 	return (statp->nscount);
870 }
871 
872 /*! \file */
873