1/*	$NetBSD: res_init.c,v 1.1.1.1 2009/04/12 15:33:56 christos Exp $	*/
2
3/*
4 * Copyright (c) 1985, 1989, 1993
5 *    The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 * 	This product includes software developed by the University of
18 * 	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36/*
37 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
38 *
39 * Permission to use, copy, modify, and distribute this software for any
40 * purpose with or without fee is hereby granted, provided that the above
41 * copyright notice and this permission notice appear in all copies, and that
42 * the name of Digital Equipment Corporation not be used in advertising or
43 * publicity pertaining to distribution of the document or software without
44 * specific, written prior permission.
45 *
46 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
47 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
48 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
49 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
50 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
51 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
52 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
53 * SOFTWARE.
54 */
55
56/*
57 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
58 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
59 *
60 * Permission to use, copy, modify, and distribute this software for any
61 * purpose with or without fee is hereby granted, provided that the above
62 * copyright notice and this permission notice appear in all copies.
63 *
64 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
65 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
66 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
67 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
68 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
69 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
70 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
71 */
72
73#if defined(LIBC_SCCS) && !defined(lint)
74static const char sccsid[] = "@(#)res_init.c	8.1 (Berkeley) 6/7/93";
75static const char rcsid[] = "Id: res_init.c,v 1.26 2008/12/11 09:59:00 marka Exp";
76#endif /* LIBC_SCCS and not lint */
77
78#include "port_before.h"
79
80#include <sys/types.h>
81#include <sys/param.h>
82#include <sys/socket.h>
83#include <sys/time.h>
84
85#include <netinet/in.h>
86#include <arpa/inet.h>
87#include <arpa/nameser.h>
88
89#include <ctype.h>
90#include <stdio.h>
91#include <stdlib.h>
92#include <string.h>
93#include <unistd.h>
94#include <netdb.h>
95
96#ifndef HAVE_MD5
97# include "../dst/md5.h"
98#else
99# ifdef SOLARIS2
100#  include <sys/md5.h>
101# endif
102#endif
103#ifndef _MD5_H_
104# define _MD5_H_ 1	/*%< make sure we do not include rsaref md5.h file */
105#endif
106
107#include "port_after.h"
108
109/* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
110#include <resolv.h>
111
112#include "res_private.h"
113
114/*% Options.  Should all be left alone. */
115#define RESOLVSORT
116#define DEBUG
117
118#ifdef SOLARIS2
119#include <sys/systeminfo.h>
120#endif
121
122static void res_setoptions __P((res_state, const char *, const char *));
123
124#ifdef RESOLVSORT
125static const char sort_mask[] = "/&";
126#define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
127static u_int32_t net_mask __P((struct in_addr));
128#endif
129
130#if !defined(isascii)	/*%< XXX - could be a function */
131# define isascii(c) (!(c & 0200))
132#endif
133
134/*
135 * Resolver state default settings.
136 */
137
138/*%
139 * Set up default settings.  If the configuration file exist, the values
140 * there will have precedence.  Otherwise, the server address is set to
141 * INADDR_ANY and the default domain name comes from the gethostname().
142 *
143 * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
144 * rather than INADDR_ANY ("0.0.0.0") as the default name server address
145 * since it was noted that INADDR_ANY actually meant ``the first interface
146 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
147 * it had to be "up" in order for you to reach your own name server.  It
148 * was later decided that since the recommended practice is to always
149 * install local static routes through 127.0.0.1 for all your network
150 * interfaces, that we could solve this problem without a code change.
151 *
152 * The configuration file should always be used, since it is the only way
153 * to specify a default domain.  If you are running a server on your local
154 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
155 * in the configuration file.
156 *
157 * Return 0 if completes successfully, -1 on error
158 */
159int
160res_ninit(res_state statp) {
161	extern int __res_vinit(res_state, int);
162
163	return (__res_vinit(statp, 0));
164}
165
166/*% This function has to be reachable by res_data.c but not publically. */
167int
168__res_vinit(res_state statp, int preinit) {
169	register FILE *fp;
170	register char *cp, **pp;
171	register int n;
172	char buf[BUFSIZ];
173	int nserv = 0;    /*%< number of nameserver records read from file */
174	int haveenv = 0;
175	int havesearch = 0;
176#ifdef RESOLVSORT
177	int nsort = 0;
178	char *net;
179#endif
180	int dots;
181	union res_sockaddr_union u[2];
182	int maxns = MAXNS;
183
184	RES_SET_H_ERRNO(statp, 0);
185	if (statp->_u._ext.ext != NULL)
186		res_ndestroy(statp);
187
188	if (!preinit) {
189		statp->retrans = RES_TIMEOUT;
190		statp->retry = RES_DFLRETRY;
191		statp->options = RES_DEFAULT;
192		res_rndinit(statp);
193		statp->id = res_nrandomid(statp);
194	}
195
196	memset(u, 0, sizeof(u));
197#ifdef USELOOPBACK
198	u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
199#else
200	u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
201#endif
202	u[nserv].sin.sin_family = AF_INET;
203	u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
204#ifdef HAVE_SA_LEN
205	u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
206#endif
207	nserv++;
208#ifdef HAS_INET6_STRUCTS
209#ifdef USELOOPBACK
210	u[nserv].sin6.sin6_addr = in6addr_loopback;
211#else
212	u[nserv].sin6.sin6_addr = in6addr_any;
213#endif
214	u[nserv].sin6.sin6_family = AF_INET6;
215	u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
216#ifdef HAVE_SA_LEN
217	u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
218#endif
219	nserv++;
220#endif
221	statp->nscount = 0;
222	statp->ndots = 1;
223	statp->pfcode = 0;
224	statp->_vcsock = -1;
225	statp->_flags = 0;
226	statp->qhook = NULL;
227	statp->rhook = NULL;
228	statp->_u._ext.nscount = 0;
229	statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
230	if (statp->_u._ext.ext != NULL) {
231	        memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
232		statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
233		strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
234		strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
235	} else {
236		/*
237		 * Historically res_init() rarely, if at all, failed.
238		 * Examples and applications exist which do not check
239		 * our return code.  Furthermore several applications
240		 * simply call us to get the systems domainname.  So
241		 * rather then immediately fail here we store the
242		 * failure, which is returned later, in h_errno.  And
243		 * prevent the collection of 'nameserver' information
244		 * by setting maxns to 0.  Thus applications that fail
245		 * to check our return code wont be able to make
246		 * queries anyhow.
247		 */
248		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
249		maxns = 0;
250	}
251#ifdef RESOLVSORT
252	statp->nsort = 0;
253#endif
254	res_setservers(statp, u, nserv);
255
256#ifdef	SOLARIS2
257	/*
258	 * The old libresolv derived the defaultdomain from NIS/NIS+.
259	 * We want to keep this behaviour
260	 */
261	{
262		char buf[sizeof(statp->defdname)], *cp;
263		int ret;
264
265		if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 &&
266			(unsigned int)ret <= sizeof(buf)) {
267			if (buf[0] == '+')
268				buf[0] = '.';
269			cp = strchr(buf, '.');
270			cp = (cp == NULL) ? buf : (cp + 1);
271			strncpy(statp->defdname, cp,
272				sizeof(statp->defdname) - 1);
273			statp->defdname[sizeof(statp->defdname) - 1] = '\0';
274		}
275	}
276#endif	/* SOLARIS2 */
277
278	/* Allow user to override the local domain definition */
279	if ((cp = getenv("LOCALDOMAIN")) != NULL) {
280		(void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
281		statp->defdname[sizeof(statp->defdname) - 1] = '\0';
282		haveenv++;
283
284		/*
285		 * Set search list to be blank-separated strings
286		 * from rest of env value.  Permits users of LOCALDOMAIN
287		 * to still have a search list, and anyone to set the
288		 * one that they want to use as an individual (even more
289		 * important now that the rfc1535 stuff restricts searches)
290		 */
291		cp = statp->defdname;
292		pp = statp->dnsrch;
293		*pp++ = cp;
294		for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
295			if (*cp == '\n')	/*%< silly backwards compat */
296				break;
297			else if (*cp == ' ' || *cp == '\t') {
298				*cp = 0;
299				n = 1;
300			} else if (n) {
301				*pp++ = cp;
302				n = 0;
303				havesearch = 1;
304			}
305		}
306		/* null terminate last domain if there are excess */
307		while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
308			cp++;
309		*cp = '\0';
310		*pp++ = 0;
311	}
312
313#define	MATCH(line, name) \
314	(!strncmp(line, name, sizeof(name) - 1) && \
315	(line[sizeof(name) - 1] == ' ' || \
316	 line[sizeof(name) - 1] == '\t'))
317
318	nserv = 0;
319	if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
320	    /* read the config file */
321	    while (fgets(buf, sizeof(buf), fp) != NULL) {
322		/* skip comments */
323		if (*buf == ';' || *buf == '#')
324			continue;
325		/* read default domain name */
326		if (MATCH(buf, "domain")) {
327		    if (haveenv)	/*%< skip if have from environ */
328			    continue;
329		    cp = buf + sizeof("domain") - 1;
330		    while (*cp == ' ' || *cp == '\t')
331			    cp++;
332		    if ((*cp == '\0') || (*cp == '\n'))
333			    continue;
334		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
335		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
336		    if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
337			    *cp = '\0';
338		    havesearch = 0;
339		    continue;
340		}
341		/* set search list */
342		if (MATCH(buf, "search")) {
343		    if (haveenv)	/*%< skip if have from environ */
344			    continue;
345		    cp = buf + sizeof("search") - 1;
346		    while (*cp == ' ' || *cp == '\t')
347			    cp++;
348		    if ((*cp == '\0') || (*cp == '\n'))
349			    continue;
350		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
351		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
352		    if ((cp = strchr(statp->defdname, '\n')) != NULL)
353			    *cp = '\0';
354		    /*
355		     * Set search list to be blank-separated strings
356		     * on rest of line.
357		     */
358		    cp = statp->defdname;
359		    pp = statp->dnsrch;
360		    *pp++ = cp;
361		    for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
362			    if (*cp == ' ' || *cp == '\t') {
363				    *cp = 0;
364				    n = 1;
365			    } else if (n) {
366				    *pp++ = cp;
367				    n = 0;
368			    }
369		    }
370		    /* null terminate last domain if there are excess */
371		    while (*cp != '\0' && *cp != ' ' && *cp != '\t')
372			    cp++;
373		    *cp = '\0';
374		    *pp++ = 0;
375		    havesearch = 1;
376		    continue;
377		}
378		/* read nameservers to query */
379		if (MATCH(buf, "nameserver") && nserv < maxns) {
380		    struct addrinfo hints, *ai;
381		    char sbuf[NI_MAXSERV];
382		    const size_t minsiz =
383		        sizeof(statp->_u._ext.ext->nsaddrs[0]);
384
385		    cp = buf + sizeof("nameserver") - 1;
386		    while (*cp == ' ' || *cp == '\t')
387			cp++;
388		    cp[strcspn(cp, ";# \t\n")] = '\0';
389		    if ((*cp != '\0') && (*cp != '\n')) {
390			memset(&hints, 0, sizeof(hints));
391			hints.ai_family = PF_UNSPEC;
392			hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
393			hints.ai_flags = AI_NUMERICHOST;
394			sprintf(sbuf, "%u", NAMESERVER_PORT);
395			if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
396			    ai->ai_addrlen <= minsiz) {
397			    if (statp->_u._ext.ext != NULL) {
398				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
399				    ai->ai_addr, ai->ai_addrlen);
400			    }
401			    if (ai->ai_addrlen <=
402			        sizeof(statp->nsaddr_list[nserv])) {
403				memcpy(&statp->nsaddr_list[nserv],
404				    ai->ai_addr, ai->ai_addrlen);
405			    } else
406				statp->nsaddr_list[nserv].sin_family = 0;
407			    freeaddrinfo(ai);
408			    nserv++;
409			}
410		    }
411		    continue;
412		}
413#ifdef RESOLVSORT
414		if (MATCH(buf, "sortlist")) {
415		    struct in_addr a;
416
417		    cp = buf + sizeof("sortlist") - 1;
418		    while (nsort < MAXRESOLVSORT) {
419			while (*cp == ' ' || *cp == '\t')
420			    cp++;
421			if (*cp == '\0' || *cp == '\n' || *cp == ';')
422			    break;
423			net = cp;
424			while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
425			       isascii(*cp) && !isspace((unsigned char)*cp))
426				cp++;
427			n = *cp;
428			*cp = 0;
429			if (inet_aton(net, &a)) {
430			    statp->sort_list[nsort].addr = a;
431			    if (ISSORTMASK(n)) {
432				*cp++ = n;
433				net = cp;
434				while (*cp && *cp != ';' &&
435					isascii(*cp) &&
436					!isspace((unsigned char)*cp))
437				    cp++;
438				n = *cp;
439				*cp = 0;
440				if (inet_aton(net, &a)) {
441				    statp->sort_list[nsort].mask = a.s_addr;
442				} else {
443				    statp->sort_list[nsort].mask =
444					net_mask(statp->sort_list[nsort].addr);
445				}
446			    } else {
447				statp->sort_list[nsort].mask =
448				    net_mask(statp->sort_list[nsort].addr);
449			    }
450			    nsort++;
451			}
452			*cp = n;
453		    }
454		    continue;
455		}
456#endif
457		if (MATCH(buf, "options")) {
458		    res_setoptions(statp, buf + sizeof("options") - 1, "conf");
459		    continue;
460		}
461	    }
462	    if (nserv > 0)
463		statp->nscount = nserv;
464#ifdef RESOLVSORT
465	    statp->nsort = nsort;
466#endif
467	    (void) fclose(fp);
468	}
469/*
470 * Last chance to get a nameserver.  This should not normally
471 * be necessary
472 */
473#ifdef NO_RESOLV_CONF
474	if(nserv == 0)
475		nserv = get_nameservers(statp);
476#endif
477
478	if (statp->defdname[0] == 0 &&
479	    gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
480	    (cp = strchr(buf, '.')) != NULL)
481		strcpy(statp->defdname, cp + 1);
482
483	/* find components of local domain that might be searched */
484	if (havesearch == 0) {
485		pp = statp->dnsrch;
486		*pp++ = statp->defdname;
487		*pp = NULL;
488
489		dots = 0;
490		for (cp = statp->defdname; *cp; cp++)
491			dots += (*cp == '.');
492
493		cp = statp->defdname;
494		while (pp < statp->dnsrch + MAXDFLSRCH) {
495			if (dots < LOCALDOMAINPARTS)
496				break;
497			cp = strchr(cp, '.') + 1;    /*%< we know there is one */
498			*pp++ = cp;
499			dots--;
500		}
501		*pp = NULL;
502#ifdef DEBUG
503		if (statp->options & RES_DEBUG) {
504			printf(";; res_init()... default dnsrch list:\n");
505			for (pp = statp->dnsrch; *pp; pp++)
506				printf(";;\t%s\n", *pp);
507			printf(";;\t..END..\n");
508		}
509#endif
510	}
511
512	if ((cp = getenv("RES_OPTIONS")) != NULL)
513		res_setoptions(statp, cp, "env");
514	statp->options |= RES_INIT;
515	return (statp->res_h_errno);
516}
517
518static void
519res_setoptions(res_state statp, const char *options, const char *source)
520{
521	const char *cp = options;
522	int i;
523	struct __res_state_ext *ext = statp->_u._ext.ext;
524
525#ifdef DEBUG
526	if (statp->options & RES_DEBUG)
527		printf(";; res_setoptions(\"%s\", \"%s\")...\n",
528		       options, source);
529#endif
530	while (*cp) {
531		/* skip leading and inner runs of spaces */
532		while (*cp == ' ' || *cp == '\t')
533			cp++;
534		/* search for and process individual options */
535		if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
536			i = atoi(cp + sizeof("ndots:") - 1);
537			if (i <= RES_MAXNDOTS)
538				statp->ndots = i;
539			else
540				statp->ndots = RES_MAXNDOTS;
541#ifdef DEBUG
542			if (statp->options & RES_DEBUG)
543				printf(";;\tndots=%d\n", statp->ndots);
544#endif
545		} else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
546			i = atoi(cp + sizeof("timeout:") - 1);
547			if (i <= RES_MAXRETRANS)
548				statp->retrans = i;
549			else
550				statp->retrans = RES_MAXRETRANS;
551#ifdef DEBUG
552			if (statp->options & RES_DEBUG)
553				printf(";;\ttimeout=%d\n", statp->retrans);
554#endif
555#ifdef	SOLARIS2
556		} else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) {
557			/*
558		 	 * For backward compatibility, 'retrans' is
559		 	 * supported as an alias for 'timeout', though
560		 	 * without an imposed maximum.
561		 	 */
562			statp->retrans = atoi(cp + sizeof("retrans:") - 1);
563		} else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){
564			/*
565			 * For backward compatibility, 'retry' is
566			 * supported as an alias for 'attempts', though
567			 * without an imposed maximum.
568			 */
569			statp->retry = atoi(cp + sizeof("retry:") - 1);
570#endif	/* SOLARIS2 */
571		} else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
572			i = atoi(cp + sizeof("attempts:") - 1);
573			if (i <= RES_MAXRETRY)
574				statp->retry = i;
575			else
576				statp->retry = RES_MAXRETRY;
577#ifdef DEBUG
578			if (statp->options & RES_DEBUG)
579				printf(";;\tattempts=%d\n", statp->retry);
580#endif
581		} else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
582#ifdef DEBUG
583			if (!(statp->options & RES_DEBUG)) {
584				printf(";; res_setoptions(\"%s\", \"%s\")..\n",
585				       options, source);
586				statp->options |= RES_DEBUG;
587			}
588			printf(";;\tdebug\n");
589#endif
590		} else if (!strncmp(cp, "no_tld_query",
591				    sizeof("no_tld_query") - 1) ||
592			   !strncmp(cp, "no-tld-query",
593				    sizeof("no-tld-query") - 1)) {
594			statp->options |= RES_NOTLDQUERY;
595		} else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
596			statp->options |= RES_USE_INET6;
597		} else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
598			statp->options |= RES_ROTATE;
599		} else if (!strncmp(cp, "no-check-names",
600				    sizeof("no-check-names") - 1)) {
601			statp->options |= RES_NOCHECKNAME;
602		}
603#ifdef RES_USE_EDNS0
604		else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
605			statp->options |= RES_USE_EDNS0;
606		}
607#endif
608		else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
609			statp->options |= RES_USE_DNAME;
610		}
611		else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
612			if (ext == NULL)
613				goto skip;
614			cp += sizeof("nibble:") - 1;
615			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
616			strncpy(ext->nsuffix, cp, i);
617			ext->nsuffix[i] = '\0';
618		}
619		else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
620			if (ext == NULL)
621				goto skip;
622			cp += sizeof("nibble2:") - 1;
623			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
624			strncpy(ext->nsuffix2, cp, i);
625			ext->nsuffix2[i] = '\0';
626		}
627		else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
628			cp += sizeof("v6revmode:") - 1;
629			/* "nibble" and "bitstring" used to be valid */
630			if (!strncmp(cp, "single", sizeof("single") - 1)) {
631				statp->options |= RES_NO_NIBBLE2;
632			} else if (!strncmp(cp, "both", sizeof("both") - 1)) {
633				statp->options &=
634					 ~RES_NO_NIBBLE2;
635			}
636		}
637		else {
638			/* XXX - print a warning here? */
639		}
640   skip:
641		/* skip to next run of spaces */
642		while (*cp && *cp != ' ' && *cp != '\t')
643			cp++;
644	}
645}
646
647#ifdef RESOLVSORT
648/* XXX - should really support CIDR which means explicit masks always. */
649static u_int32_t
650net_mask(in)		/*!< XXX - should really use system's version of this  */
651	struct in_addr in;
652{
653	register u_int32_t i = ntohl(in.s_addr);
654
655	if (IN_CLASSA(i))
656		return (htonl(IN_CLASSA_NET));
657	else if (IN_CLASSB(i))
658		return (htonl(IN_CLASSB_NET));
659	return (htonl(IN_CLASSC_NET));
660}
661#endif
662
663void
664res_rndinit(res_state statp)
665{
666	struct timeval now;
667	u_int32_t u32;
668	u_int16_t u16;
669
670	gettimeofday(&now, NULL);
671	u32 = now.tv_sec;
672	memcpy(statp->_rnd, &u32, 4);
673	u32 = now.tv_usec;
674	memcpy(statp->_rnd + 4, &u32, 4);
675	u32 += now.tv_sec;
676	memcpy(statp->_rnd + 8, &u32, 4);
677	u16 = getpid();
678	memcpy(statp->_rnd + 12, &u16, 2);
679}
680
681u_int
682res_nrandomid(res_state statp) {
683	struct timeval now;
684	u_int16_t u16;
685	MD5_CTX ctx;
686
687	gettimeofday(&now, NULL);
688	u16 = (u_int16_t) (now.tv_sec ^ now.tv_usec);
689	memcpy(statp->_rnd + 14, &u16, 2);
690#ifndef HAVE_MD5
691	MD5_Init(&ctx);
692	MD5_Update(&ctx, statp->_rnd, 16);
693	MD5_Final(statp->_rnd, &ctx);
694#else
695	MD5Init(&ctx);
696	MD5Update(&ctx, statp->_rnd, 16);
697	MD5Final(statp->_rnd, &ctx);
698#endif
699	memcpy(&u16, statp->_rnd + 14, 2);
700	return ((u_int) u16);
701}
702
703/*%
704 * This routine is for closing the socket if a virtual circuit is used and
705 * the program wants to close it.  This provides support for endhostent()
706 * which expects to close the socket.
707 *
708 * This routine is not expected to be user visible.
709 */
710void
711res_nclose(res_state statp) {
712	int ns;
713
714	if (statp->_vcsock >= 0) {
715		(void) close(statp->_vcsock);
716		statp->_vcsock = -1;
717		statp->_flags &= ~(RES_F_VC | RES_F_CONN);
718	}
719	for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
720		if (statp->_u._ext.nssocks[ns] != -1) {
721			(void) close(statp->_u._ext.nssocks[ns]);
722			statp->_u._ext.nssocks[ns] = -1;
723		}
724	}
725}
726
727void
728res_ndestroy(res_state statp) {
729	res_nclose(statp);
730	if (statp->_u._ext.ext != NULL)
731		free(statp->_u._ext.ext);
732	statp->options &= ~RES_INIT;
733	statp->_u._ext.ext = NULL;
734}
735
736const char *
737res_get_nibblesuffix(res_state statp) {
738	if (statp->_u._ext.ext)
739		return (statp->_u._ext.ext->nsuffix);
740	return ("ip6.arpa");
741}
742
743const char *
744res_get_nibblesuffix2(res_state statp) {
745	if (statp->_u._ext.ext)
746		return (statp->_u._ext.ext->nsuffix2);
747	return ("ip6.int");
748}
749
750void
751res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
752	int i, nserv;
753	size_t size;
754
755	/* close open servers */
756	res_nclose(statp);
757
758	/* cause rtt times to be forgotten */
759	statp->_u._ext.nscount = 0;
760
761	nserv = 0;
762	for (i = 0; i < cnt && nserv < MAXNS; i++) {
763		switch (set->sin.sin_family) {
764		case AF_INET:
765			size = sizeof(set->sin);
766			if (statp->_u._ext.ext)
767				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
768					&set->sin, size);
769			if (size <= sizeof(statp->nsaddr_list[nserv]))
770				memcpy(&statp->nsaddr_list[nserv],
771					&set->sin, size);
772			else
773				statp->nsaddr_list[nserv].sin_family = 0;
774			nserv++;
775			break;
776
777#ifdef HAS_INET6_STRUCTS
778		case AF_INET6:
779			size = sizeof(set->sin6);
780			if (statp->_u._ext.ext)
781				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
782					&set->sin6, size);
783			if (size <= sizeof(statp->nsaddr_list[nserv]))
784				memcpy(&statp->nsaddr_list[nserv],
785					&set->sin6, size);
786			else
787				statp->nsaddr_list[nserv].sin_family = 0;
788			nserv++;
789			break;
790#endif
791
792		default:
793			break;
794		}
795		set++;
796	}
797	statp->nscount = nserv;
798
799}
800
801int
802res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
803	int i;
804	size_t size;
805	u_int16_t family;
806
807	for (i = 0; i < statp->nscount && i < cnt; i++) {
808		if (statp->_u._ext.ext)
809			family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
810		else
811			family = statp->nsaddr_list[i].sin_family;
812
813		switch (family) {
814		case AF_INET:
815			size = sizeof(set->sin);
816			if (statp->_u._ext.ext)
817				memcpy(&set->sin,
818				       &statp->_u._ext.ext->nsaddrs[i],
819				       size);
820			else
821				memcpy(&set->sin, &statp->nsaddr_list[i],
822				       size);
823			break;
824
825#ifdef HAS_INET6_STRUCTS
826		case AF_INET6:
827			size = sizeof(set->sin6);
828			if (statp->_u._ext.ext)
829				memcpy(&set->sin6,
830				       &statp->_u._ext.ext->nsaddrs[i],
831				       size);
832			else
833				memcpy(&set->sin6, &statp->nsaddr_list[i],
834				       size);
835			break;
836#endif
837
838		default:
839			set->sin.sin_family = 0;
840			break;
841		}
842		set++;
843	}
844	return (statp->nscount);
845}
846
847/*! \file */
848