xref: /freebsd/lib/libc/resolv/res_init.c (revision dafba19e42e78cd3d7c9264ece49ddd3d7d70da5)
1 /*-
2  * SPDX-License-Identifier: (BSD-3-Clause AND ISC)
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. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*
33  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
34  *
35  * Permission to use, copy, modify, and distribute this software for any
36  * purpose with or without fee is hereby granted, provided that the above
37  * copyright notice and this permission notice appear in all copies, and that
38  * the name of Digital Equipment Corporation not be used in advertising or
39  * publicity pertaining to distribution of the document or software without
40  * specific, written prior permission.
41  *
42  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
43  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
44  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
45  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
46  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
47  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
48  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
49  * SOFTWARE.
50  */
51 
52 /*
53  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
54  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
55  *
56  * Permission to use, copy, modify, and distribute this software for any
57  * purpose with or without fee is hereby granted, provided that the above
58  * copyright notice and this permission notice appear in all copies.
59  *
60  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
61  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
62  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
63  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
64  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
65  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
66  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
67  */
68 
69 #include "port_before.h"
70 
71 #include "namespace.h"
72 
73 #include <sys/param.h>
74 #include <sys/socket.h>
75 #include <sys/stat.h>
76 #include <sys/time.h>
77 
78 #include <netinet/in.h>
79 #include <arpa/inet.h>
80 #include <arpa/nameser.h>
81 
82 #include <ctype.h>
83 #include <stdio.h>
84 #include <stdlib.h>
85 #include <string.h>
86 #include <unistd.h>
87 #include <netdb.h>
88 
89 #include "un-namespace.h"
90 
91 #include "port_after.h"
92 
93 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
94 #include <resolv.h>
95 
96 #include "res_private.h"
97 
98 #ifdef SOLARIS2
99 #include <sys/systeminfo.h>
100 #endif
101 
102 static void res_setoptions(res_state, const char *, const char *);
103 
104 #ifdef RESOLVSORT
105 static const char sort_mask[] = "/&";
106 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
107 static u_int32_t net_mask(struct in_addr);
108 #endif
109 
110 #if !defined(isascii)	/*%< XXX - could be a function */
111 # define isascii(c) (!(c & 0200))
112 #endif
113 
114 /*
115  * Resolver state default settings.
116  */
117 
118 /*%
119  * Set up default settings.  If the configuration file exist, the values
120  * there will have precedence.  Otherwise, the server address is set to
121  * the loopback address the default domain name comes from gethostname().
122  *
123  * The configuration file should always be used, since it is the only way
124  * to specify options and a default domain.  If you are running a server
125  * on your local machine, you should say "nameserver 127.0.0.1" or
126  * "nameserver ::1" in the configuration file.
127  *
128  * Return 0 if completes successfully, -1 on error
129  */
130 int
131 res_ninit(res_state statp) {
132 	extern int __res_vinit(res_state, int);
133 
134 	return (__res_vinit(statp, 0));
135 }
136 
137 /*% This function has to be reachable by res_data.c but not publicly. */
138 int
139 __res_vinit(res_state statp, int preinit) {
140 	union res_sockaddr_union u[] = {
141 		{ .sin = {
142 			.sin_family = AF_INET,
143 #ifdef HAVE_SA_LEN
144 			.sin_len = sizeof(struct sockaddr_in),
145 #endif
146 			.sin_port = htons(NAMESERVER_PORT),
147 			.sin_addr = { htonl(INADDR_LOOPBACK) },
148 		} },
149 #ifdef HAS_INET6_STRUCTS
150 		{ .sin6 = {
151 			.sin6_family = AF_INET6,
152 #ifdef HAVE_SA_LEN
153 			.sin6_len = sizeof(struct sockaddr_in6),
154 #endif
155 			.sin6_port = htons(NAMESERVER_PORT),
156 			.sin6_addr = IN6ADDR_LOOPBACK_INIT,
157 		} },
158 #endif
159 	};
160 	FILE *fp;
161 	char *cp, **pp;
162 	int n;
163 	char buf[BUFSIZ];
164 	int nserv = 0;    /*%< number of nameserver records read from file */
165 	int haveenv = 0;
166 	int havesearch = 0;
167 #ifdef RESOLVSORT
168 	int nsort = 0;
169 	char *net;
170 #endif
171 	int dots;
172 	int maxns = MAXNS;
173 
174 	RES_SET_H_ERRNO(statp, 0);
175 	if (statp->_u._ext.ext != NULL)
176 		res_ndestroy(statp);
177 
178 	if (!preinit) {
179 		statp->retrans = RES_TIMEOUT;
180 		statp->retry = RES_DFLRETRY;
181 		statp->options = RES_DEFAULT;
182 	}
183 
184 	statp->id = res_nrandomid(statp);
185 
186 	statp->nscount = 0;
187 	statp->ndots = 1;
188 	statp->pfcode = 0;
189 	statp->_vcsock = -1;
190 	statp->_flags = 0;
191 	statp->qhook = NULL;
192 	statp->rhook = NULL;
193 	statp->_u._ext.nscount = 0;
194 	statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
195 	if (statp->_u._ext.ext != NULL) {
196 	        memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
197 		statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
198 		strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
199 		strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
200 		statp->_u._ext.ext->reload_period = 2;
201 	} else {
202 		/*
203 		 * Historically res_init() rarely, if at all, failed.
204 		 * Examples and applications exist which do not check
205 		 * our return code.  Furthermore several applications
206 		 * simply call us to get the systems domainname.  So
207 		 * rather then immediately fail here we store the
208 		 * failure, which is returned later, in h_errno.  And
209 		 * prevent the collection of 'nameserver' information
210 		 * by setting maxns to 0.  Thus applications that fail
211 		 * to check our return code wont be able to make
212 		 * queries anyhow.
213 		 */
214 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
215 		maxns = 0;
216 	}
217 #ifdef RESOLVSORT
218 	statp->nsort = 0;
219 #endif
220 	res_setservers(statp, u, nitems(u));
221 
222 #ifdef	SOLARIS2
223 	/*
224 	 * The old libresolv derived the defaultdomain from NIS/NIS+.
225 	 * We want to keep this behaviour
226 	 */
227 	{
228 		char buf[sizeof(statp->defdname)], *cp;
229 		int ret;
230 
231 		if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 &&
232 			(unsigned int)ret <= sizeof(buf)) {
233 			if (buf[0] == '+')
234 				buf[0] = '.';
235 			cp = strchr(buf, '.');
236 			cp = (cp == NULL) ? buf : (cp + 1);
237 			strncpy(statp->defdname, cp,
238 				sizeof(statp->defdname) - 1);
239 			statp->defdname[sizeof(statp->defdname) - 1] = '\0';
240 		}
241 	}
242 #endif	/* SOLARIS2 */
243 
244 	/* Allow user to override the local domain definition */
245 	if ((cp = secure_getenv("LOCALDOMAIN")) != NULL) {
246 		(void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
247 		statp->defdname[sizeof(statp->defdname) - 1] = '\0';
248 		haveenv++;
249 
250 		/*
251 		 * Set search list to be blank-separated strings
252 		 * from rest of env value.  Permits users of LOCALDOMAIN
253 		 * to still have a search list, and anyone to set the
254 		 * one that they want to use as an individual (even more
255 		 * important now that the rfc1535 stuff restricts searches)
256 		 */
257 		cp = statp->defdname;
258 		pp = statp->dnsrch;
259 		*pp++ = cp;
260 		for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
261 			if (*cp == '\n')	/*%< silly backwards compat */
262 				break;
263 			else if (*cp == ' ' || *cp == '\t') {
264 				*cp = 0;
265 				n = 1;
266 			} else if (n) {
267 				*pp++ = cp;
268 				n = 0;
269 				havesearch = 1;
270 			}
271 		}
272 		/* null terminate last domain if there are excess */
273 		while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
274 			cp++;
275 		*cp = '\0';
276 		*pp++ = NULL;
277 	}
278 
279 #define	MATCH(line, name) \
280 	(!strncmp(line, name, sizeof(name) - 1) && \
281 	(line[sizeof(name) - 1] == ' ' || \
282 	 line[sizeof(name) - 1] == '\t'))
283 
284 	if ((fp = fopen(_PATH_RESCONF, "re")) != NULL) {
285 	    struct stat sb;
286 	    struct timespec now;
287 
288 	    if (statp->_u._ext.ext != NULL) {
289 		if (_fstat(fileno(fp), &sb) == 0) {
290 		    statp->_u._ext.ext->conf_mtim = sb.st_mtim;
291 		    if (clock_gettime(CLOCK_MONOTONIC_FAST, &now) == 0) {
292 			statp->_u._ext.ext->conf_stat = now.tv_sec;
293 		    }
294 		}
295 	    }
296 
297 	    /* read the config file */
298 	    while (fgets(buf, sizeof(buf), fp) != NULL) {
299 		/* skip comments */
300 		if (*buf == ';' || *buf == '#')
301 			continue;
302 		/* read default domain name */
303 		if (MATCH(buf, "domain")) {
304 		    if (haveenv)	/*%< skip if have from environ */
305 			    continue;
306 		    cp = buf + sizeof("domain") - 1;
307 		    while (*cp == ' ' || *cp == '\t')
308 			    cp++;
309 		    if ((*cp == '\0') || (*cp == '\n'))
310 			    continue;
311 		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
312 		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
313 		    if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
314 			    *cp = '\0';
315 		    havesearch = 0;
316 		    continue;
317 		}
318 		/* set search list */
319 		if (MATCH(buf, "search")) {
320 		    if (haveenv)	/*%< skip if have from environ */
321 			    continue;
322 		    cp = buf + sizeof("search") - 1;
323 		    while (*cp == ' ' || *cp == '\t')
324 			    cp++;
325 		    if ((*cp == '\0') || (*cp == '\n'))
326 			    continue;
327 		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
328 		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
329 		    if ((cp = strchr(statp->defdname, '\n')) != NULL)
330 			    *cp = '\0';
331 		    /*
332 		     * Set search list to be blank-separated strings
333 		     * on rest of line.
334 		     */
335 		    cp = statp->defdname;
336 		    pp = statp->dnsrch;
337 		    *pp++ = cp;
338 		    for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
339 			    if (*cp == ' ' || *cp == '\t') {
340 				    *cp = 0;
341 				    n = 1;
342 			    } else if (n) {
343 				    *pp++ = cp;
344 				    n = 0;
345 			    }
346 		    }
347 		    /* null terminate last domain if there are excess */
348 		    while (*cp != '\0' && *cp != ' ' && *cp != '\t')
349 			    cp++;
350 		    *cp = '\0';
351 		    *pp++ = NULL;
352 		    havesearch = 1;
353 		    continue;
354 		}
355 		/* read nameservers to query */
356 		if (MATCH(buf, "nameserver") && nserv < maxns) {
357 		    struct addrinfo hints, *ai;
358 		    char sbuf[NI_MAXSERV];
359 		    const size_t minsiz =
360 		        sizeof(statp->_u._ext.ext->nsaddrs[0]);
361 
362 		    cp = buf + sizeof("nameserver") - 1;
363 		    while (*cp == ' ' || *cp == '\t')
364 			cp++;
365 		    cp[strcspn(cp, ";# \t\n")] = '\0';
366 		    if ((*cp != '\0') && (*cp != '\n')) {
367 			memset(&hints, 0, sizeof(hints));
368 			hints.ai_family = PF_UNSPEC;
369 			hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
370 			hints.ai_flags = AI_NUMERICHOST;
371 			sprintf(sbuf, "%u", NAMESERVER_PORT);
372 			if (getaddrinfo(cp, sbuf, &hints, &ai) == 0) {
373 			    if (ai->ai_addrlen <= minsiz) {
374 				if (statp->_u._ext.ext != NULL) {
375 				    memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
376 					ai->ai_addr, ai->ai_addrlen);
377 				}
378 				if (ai->ai_addrlen <=
379 				    sizeof(statp->nsaddr_list[nserv])) {
380 				    memcpy(&statp->nsaddr_list[nserv],
381 					ai->ai_addr, ai->ai_addrlen);
382 				} else
383 				    statp->nsaddr_list[nserv].sin_family = 0;
384 				nserv++;
385 			    }
386 			    freeaddrinfo(ai);
387 			}
388 		    }
389 		    continue;
390 		}
391 #ifdef RESOLVSORT
392 		if (MATCH(buf, "sortlist")) {
393 		    struct in_addr a;
394 		    struct in6_addr a6;
395 		    int m, i;
396 		    u_char *u;
397 		    struct __res_state_ext *ext = statp->_u._ext.ext;
398 
399 		    cp = buf + sizeof("sortlist") - 1;
400 		    while (nsort < MAXRESOLVSORT) {
401 			while (*cp == ' ' || *cp == '\t')
402 			    cp++;
403 			if (*cp == '\0' || *cp == '\n' || *cp == ';')
404 			    break;
405 			net = cp;
406 			while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
407 			       isascii(*cp) && !isspace((unsigned char)*cp))
408 				cp++;
409 			n = *cp;
410 			*cp = 0;
411 			if (inet_aton(net, &a)) {
412 			    statp->sort_list[nsort].addr = a;
413 			    if (ISSORTMASK(n)) {
414 				*cp++ = n;
415 				net = cp;
416 				while (*cp && *cp != ';' &&
417 					isascii(*cp) &&
418 					!isspace((unsigned char)*cp))
419 				    cp++;
420 				n = *cp;
421 				*cp = 0;
422 				if (inet_aton(net, &a)) {
423 				    statp->sort_list[nsort].mask = a.s_addr;
424 				} else {
425 				    statp->sort_list[nsort].mask =
426 					net_mask(statp->sort_list[nsort].addr);
427 				}
428 			    } else {
429 				statp->sort_list[nsort].mask =
430 				    net_mask(statp->sort_list[nsort].addr);
431 			    }
432 			    ext->sort_list[nsort].af = AF_INET;
433 			    ext->sort_list[nsort].addr.ina =
434 				statp->sort_list[nsort].addr;
435 			    ext->sort_list[nsort].mask.ina.s_addr =
436 				statp->sort_list[nsort].mask;
437 			    nsort++;
438 			}
439 			else if (inet_pton(AF_INET6, net, &a6) == 1) {
440 
441 			    ext->sort_list[nsort].af = AF_INET6;
442 			    ext->sort_list[nsort].addr.in6a = a6;
443 			    u = (u_char *)&ext->sort_list[nsort].mask.in6a;
444 			    *cp++ = n;
445 			    net = cp;
446 			    while (*cp && *cp != ';' &&
447 				    isascii(*cp) && !isspace(*cp))
448 				cp++;
449 			    m = n;
450 			    n = *cp;
451 			    *cp = 0;
452 			    switch (m) {
453 			    case '/':
454 				m = atoi(net);
455 				break;
456 			    case '&':
457 				if (inet_pton(AF_INET6, net, u) == 1) {
458 				    m = -1;
459 				    break;
460 				}
461 				/*FALLTHROUGH*/
462 			    default:
463 				m = sizeof(struct in6_addr) * CHAR_BIT;
464 				break;
465 			    }
466 			    if (m >= 0) {
467 				for (i = 0; i < sizeof(struct in6_addr); i++) {
468 				    if (m <= 0) {
469 					*u = 0;
470 				    } else {
471 					m -= CHAR_BIT;
472 					*u = (u_char)~0;
473 					if (m < 0)
474 					    *u <<= -m;
475 				    }
476 				    u++;
477 				}
478 			    }
479 			    statp->sort_list[nsort].addr.s_addr =
480 				(u_int32_t)0xffffffff;
481 			    statp->sort_list[nsort].mask =
482 				(u_int32_t)0xffffffff;
483 			    nsort++;
484 			}
485 			*cp = n;
486 		    }
487 		    continue;
488 		}
489 #endif
490 		if (MATCH(buf, "options")) {
491 		    res_setoptions(statp, buf + sizeof("options") - 1, "conf");
492 		    continue;
493 		}
494 	    }
495 	    if (nserv > 0)
496 		statp->nscount = nserv;
497 #ifdef RESOLVSORT
498 	    statp->nsort = nsort;
499 #endif
500 	    (void) fclose(fp);
501 	}
502 
503 	/* guess default domain if not set */
504 	if (statp->defdname[0] == 0 &&
505 	    gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
506 	    (cp = strchr(buf, '.')) != NULL)
507 		strcpy(statp->defdname, cp + 1);
508 
509 	/* find components of local domain that might be searched */
510 	if (havesearch == 0) {
511 		pp = statp->dnsrch;
512 		*pp++ = statp->defdname;
513 		*pp = NULL;
514 
515 		dots = 0;
516 		for (cp = statp->defdname; *cp; cp++)
517 			dots += (*cp == '.');
518 
519 		cp = statp->defdname;
520 		while (pp < statp->dnsrch + MAXDFLSRCH) {
521 			if (dots < LOCALDOMAINPARTS)
522 				break;
523 			cp = strchr(cp, '.') + 1;    /*%< we know there is one */
524 			*pp++ = cp;
525 			dots--;
526 		}
527 		*pp = NULL;
528 #ifdef DEBUG
529 		if (statp->options & RES_DEBUG) {
530 			printf(";; res_init()... default dnsrch list:\n");
531 			for (pp = statp->dnsrch; *pp; pp++)
532 				printf(";;\t%s\n", *pp);
533 			printf(";;\t..END..\n");
534 		}
535 #endif
536 	}
537 
538 	if (issetugid())
539 		statp->options |= RES_NOALIASES;
540 	else if ((cp = getenv("RES_OPTIONS")) != NULL)
541 		res_setoptions(statp, cp, "env");
542 	statp->options |= RES_INIT;
543 	return (statp->res_h_errno);
544 }
545 
546 static void
547 res_setoptions(res_state statp, const char *options, const char *source)
548 {
549 	const char *cp = options;
550 	int i;
551 	struct __res_state_ext *ext = statp->_u._ext.ext;
552 
553 #ifdef DEBUG
554 	if (statp->options & RES_DEBUG)
555 		printf(";; res_setoptions(\"%s\", \"%s\")...\n",
556 		       options, source);
557 #endif
558 	while (*cp) {
559 		/* skip leading and inner runs of spaces */
560 		while (*cp == ' ' || *cp == '\t')
561 			cp++;
562 		/* search for and process individual options */
563 		if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
564 			i = atoi(cp + sizeof("ndots:") - 1);
565 			if (i <= RES_MAXNDOTS)
566 				statp->ndots = i;
567 			else
568 				statp->ndots = RES_MAXNDOTS;
569 #ifdef DEBUG
570 			if (statp->options & RES_DEBUG)
571 				printf(";;\tndots=%d\n", statp->ndots);
572 #endif
573 		} else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
574 			i = atoi(cp + sizeof("timeout:") - 1);
575 			if (i <= RES_MAXRETRANS)
576 				statp->retrans = i;
577 			else
578 				statp->retrans = RES_MAXRETRANS;
579 #ifdef DEBUG
580 			if (statp->options & RES_DEBUG)
581 				printf(";;\ttimeout=%d\n", statp->retrans);
582 #endif
583 #ifdef	SOLARIS2
584 		} else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) {
585 			/*
586 		 	 * For backward compatibility, 'retrans' is
587 		 	 * supported as an alias for 'timeout', though
588 		 	 * without an imposed maximum.
589 		 	 */
590 			statp->retrans = atoi(cp + sizeof("retrans:") - 1);
591 		} else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){
592 			/*
593 			 * For backward compatibility, 'retry' is
594 			 * supported as an alias for 'attempts', though
595 			 * without an imposed maximum.
596 			 */
597 			statp->retry = atoi(cp + sizeof("retry:") - 1);
598 #endif	/* SOLARIS2 */
599 		} else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
600 			i = atoi(cp + sizeof("attempts:") - 1);
601 			if (i <= RES_MAXRETRY)
602 				statp->retry = i;
603 			else
604 				statp->retry = RES_MAXRETRY;
605 #ifdef DEBUG
606 			if (statp->options & RES_DEBUG)
607 				printf(";;\tattempts=%d\n", statp->retry);
608 #endif
609 		} else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
610 #ifdef DEBUG
611 			if (!(statp->options & RES_DEBUG)) {
612 				printf(";; res_setoptions(\"%s\", \"%s\")..\n",
613 				       options, source);
614 				statp->options |= RES_DEBUG;
615 			}
616 			printf(";;\tdebug\n");
617 #endif
618 		} else if (!strncmp(cp, "no_tld_query",
619 				    sizeof("no_tld_query") - 1) ||
620 			   !strncmp(cp, "no-tld-query",
621 				    sizeof("no-tld-query") - 1)) {
622 			statp->options |= RES_NOTLDQUERY;
623 		} else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
624 			statp->options |= RES_USE_INET6;
625 		} else if (!strncmp(cp, "insecure1", sizeof("insecure1") - 1)) {
626 		       statp->options |= RES_INSECURE1;
627 		} else if (!strncmp(cp, "insecure2", sizeof("insecure2") - 1)) {
628 		       statp->options |= RES_INSECURE2;
629 		} else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
630 			statp->options |= RES_ROTATE;
631 		} else if (!strncmp(cp, "usevc", sizeof("usevc") - 1)) {
632 			statp->options |= RES_USEVC;
633 		} else if (!strncmp(cp, "no-check-names",
634 				    sizeof("no-check-names") - 1)) {
635 			statp->options |= RES_NOCHECKNAME;
636 		} else if (!strncmp(cp, "reload-period:",
637 				    sizeof("reload-period:") - 1)) {
638 			if (ext != NULL) {
639 				ext->reload_period = (u_short)
640 				    atoi(cp + sizeof("reload-period:") - 1);
641 			}
642 		}
643 #ifdef RES_USE_EDNS0
644 		else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
645 			statp->options |= RES_USE_EDNS0;
646 		}
647 #endif
648 #ifndef _LIBC
649 		else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
650 			statp->options |= RES_USE_DNAME;
651 		}
652 		else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
653 			if (ext == NULL)
654 				goto skip;
655 			cp += sizeof("nibble:") - 1;
656 			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
657 			strncpy(ext->nsuffix, cp, i);
658 			ext->nsuffix[i] = '\0';
659 		}
660 		else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
661 			if (ext == NULL)
662 				goto skip;
663 			cp += sizeof("nibble2:") - 1;
664 			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
665 			strncpy(ext->nsuffix2, cp, i);
666 			ext->nsuffix2[i] = '\0';
667 		}
668 		else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
669 			cp += sizeof("v6revmode:") - 1;
670 			/* "nibble" and "bitstring" used to be valid */
671 			if (!strncmp(cp, "single", sizeof("single") - 1)) {
672 				statp->options |= RES_NO_NIBBLE2;
673 			} else if (!strncmp(cp, "both", sizeof("both") - 1)) {
674 				statp->options &=
675 					 ~RES_NO_NIBBLE2;
676 			}
677 		}
678 #endif
679 		else {
680 			/* XXX - print a warning here? */
681 		}
682 #ifndef _LIBC
683    skip:
684 #endif
685 		/* skip to next run of spaces */
686 		while (*cp && *cp != ' ' && *cp != '\t')
687 			cp++;
688 	}
689 }
690 
691 #ifdef RESOLVSORT
692 /* XXX - should really support CIDR which means explicit masks always. */
693 static u_int32_t
694 net_mask(struct in_addr in)		/*!< XXX - should really use system's version of this  */
695 {
696 	u_int32_t i = ntohl(in.s_addr);
697 
698 	if (IN_CLASSA(i))
699 		return (htonl(IN_CLASSA_NET));
700 	else if (IN_CLASSB(i))
701 		return (htonl(IN_CLASSB_NET));
702 	return (htonl(IN_CLASSC_NET));
703 }
704 #endif
705 
706 void
707 freebsd15_res_rndinit(res_state statp)
708 {
709 	(void)statp;
710 }
711 __sym_compat(__res_rndinit, freebsd15_res_rndinit, FBSD_1.4);
712 
713 u_int
714 res_nrandomid(res_state statp) {
715 	(void) statp;
716 
717 	return ((u_int)(arc4random() & 0xffff));
718 }
719 
720 /*%
721  * This routine is for closing the socket if a virtual circuit is used and
722  * the program wants to close it.  This provides support for endhostent()
723  * which expects to close the socket.
724  *
725  * This routine is not expected to be user visible.
726  */
727 void
728 res_nclose(res_state statp) {
729 	int ns;
730 
731 	if (statp->_vcsock >= 0) {
732 		(void) _close(statp->_vcsock);
733 		statp->_vcsock = -1;
734 		statp->_flags &= ~(RES_F_VC | RES_F_CONN);
735 	}
736 	for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
737 		if (statp->_u._ext.nssocks[ns] != -1) {
738 			(void) _close(statp->_u._ext.nssocks[ns]);
739 			statp->_u._ext.nssocks[ns] = -1;
740 		}
741 	}
742 }
743 
744 void
745 res_ndestroy(res_state statp) {
746 	res_nclose(statp);
747 	if (statp->_u._ext.ext != NULL) {
748 		free(statp->_u._ext.ext);
749 		statp->_u._ext.ext = NULL;
750 	}
751 	statp->options &= ~RES_INIT;
752 }
753 
754 #ifndef _LIBC
755 const char *
756 res_get_nibblesuffix(res_state statp) {
757 	if (statp->_u._ext.ext)
758 		return (statp->_u._ext.ext->nsuffix);
759 	return ("ip6.arpa");
760 }
761 
762 const char *
763 res_get_nibblesuffix2(res_state statp) {
764 	if (statp->_u._ext.ext)
765 		return (statp->_u._ext.ext->nsuffix2);
766 	return ("ip6.int");
767 }
768 #endif
769 
770 void
771 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
772 	int i, nserv;
773 	size_t size;
774 
775 	/* close open servers */
776 	res_nclose(statp);
777 
778 	/* cause rtt times to be forgotten */
779 	statp->_u._ext.nscount = 0;
780 
781 	nserv = 0;
782 	for (i = 0; i < cnt && nserv < MAXNS; i++) {
783 		switch (set->sin.sin_family) {
784 		case AF_INET:
785 			size = sizeof(set->sin);
786 			if (statp->_u._ext.ext)
787 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
788 					&set->sin, size);
789 			if (size <= sizeof(statp->nsaddr_list[nserv]))
790 				memcpy(&statp->nsaddr_list[nserv],
791 					&set->sin, size);
792 			else
793 				statp->nsaddr_list[nserv].sin_family = 0;
794 			nserv++;
795 			break;
796 
797 #ifdef HAS_INET6_STRUCTS
798 		case AF_INET6:
799 			size = sizeof(set->sin6);
800 			if (statp->_u._ext.ext)
801 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
802 					&set->sin6, size);
803 			if (size <= sizeof(statp->nsaddr_list[nserv]))
804 				memcpy(&statp->nsaddr_list[nserv],
805 					&set->sin6, size);
806 			else
807 				statp->nsaddr_list[nserv].sin_family = 0;
808 			nserv++;
809 			break;
810 #endif
811 
812 		default:
813 			break;
814 		}
815 		set++;
816 	}
817 	statp->nscount = nserv;
818 
819 }
820 
821 int
822 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
823 	int i;
824 	size_t size;
825 	u_int16_t family;
826 
827 	for (i = 0; i < statp->nscount && i < cnt; i++) {
828 		if (statp->_u._ext.ext)
829 			family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
830 		else
831 			family = statp->nsaddr_list[i].sin_family;
832 
833 		switch (family) {
834 		case AF_INET:
835 			size = sizeof(set->sin);
836 			if (statp->_u._ext.ext)
837 				memcpy(&set->sin,
838 				       &statp->_u._ext.ext->nsaddrs[i],
839 				       size);
840 			else
841 				memcpy(&set->sin, &statp->nsaddr_list[i],
842 				       size);
843 			break;
844 
845 #ifdef HAS_INET6_STRUCTS
846 		case AF_INET6:
847 			size = sizeof(set->sin6);
848 			if (statp->_u._ext.ext)
849 				memcpy(&set->sin6,
850 				       &statp->_u._ext.ext->nsaddrs[i],
851 				       size);
852 			else
853 				memcpy(&set->sin6, &statp->nsaddr_list[i],
854 				       size);
855 			break;
856 #endif
857 
858 		default:
859 			set->sin.sin_family = 0;
860 			break;
861 		}
862 		set++;
863 	}
864 	return (statp->nscount);
865 }
866 
867 /*! \file */
868