1/*	$NetBSD: res_init.c,v 1.8 2006/03/19 03:10:08 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#include <sys/cdefs.h>
74#if defined(LIBC_SCCS) && !defined(lint)
75#ifdef notdef
76static const char sccsid[] = "@(#)res_init.c	8.1 (Berkeley) 6/7/93";
77static const char rcsid[] = "Id: res_init.c,v 1.9.2.5.4.2 2004/03/16 12:34:18 marka Exp";
78#else
79__RCSID("$NetBSD: res_init.c,v 1.8 2006/03/19 03:10:08 christos Exp $");
80#endif
81#endif /* LIBC_SCCS and not lint */
82
83
84
85#include <sys/types.h>
86#include <sys/param.h>
87#include <sys/socket.h>
88#include <sys/time.h>
89
90#include <netinet/in.h>
91#include <arpa/inet.h>
92#include <arpa/nameser.h>
93
94#include <ctype.h>
95#include <stdio.h>
96#include <stdlib.h>
97#include <string.h>
98#include <unistd.h>
99#include <netdb.h>
100
101#ifdef ANDROID_CHANGES
102#include <errno.h>
103#include <fcntl.h>
104#endif /* ANDROID_CHANGES */
105
106/* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
107#ifdef ANDROID_CHANGES
108#include "resolv_netid.h"
109#include "resolv_private.h"
110#else
111#include <resolv.h>
112#endif
113
114#include "res_private.h"
115
116/* Options.  Should all be left alone. */
117#ifndef DEBUG
118#define DEBUG
119#endif
120
121static void res_setoptions __P((res_state, const char *, const char *));
122
123#ifdef RESOLVSORT
124static const char sort_mask[] = "/&";
125#define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
126static uint32_t net_mask(struct in_addr);
127#endif
128
129#if !defined(isascii)	/* XXX - could be a function */
130# define isascii(c) (!(c & 0200))
131#endif
132
133/*
134 * Resolver state default settings.
135 */
136
137/*
138 * Set up default settings.  If the configuration file exist, the values
139 * there will have precedence.  Otherwise, the server address is set to
140 * INADDR_ANY and the default domain name comes from the gethostname().
141 *
142 * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
143 * rather than INADDR_ANY ("0.0.0.0") as the default name server address
144 * since it was noted that INADDR_ANY actually meant ``the first interface
145 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
146 * it had to be "up" in order for you to reach your own name server.  It
147 * was later decided that since the recommended practice is to always
148 * install local static routes through 127.0.0.1 for all your network
149 * interfaces, that we could solve this problem without a code change.
150 *
151 * The configuration file should always be used, since it is the only way
152 * to specify a default domain.  If you are running a server on your local
153 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
154 * in the configuration file.
155 *
156 * Return 0 if completes successfully, -1 on error
157 */
158int
159res_ninit(res_state statp) {
160	extern int __res_vinit(res_state, int);
161
162	return (__res_vinit(statp, 0));
163}
164
165/* This function has to be reachable by res_data.c but not publicly. */
166int
167__res_vinit(res_state statp, int preinit) {
168#if !defined(__BIONIC__)
169	register FILE *fp;
170#endif
171	register char *cp, **pp;
172#if !defined(__BIONIC__)
173	register int n;
174#endif
175	char buf[BUFSIZ];
176	int nserv = 0;    /* number of nameserver records read from file */
177#if !defined(__BIONIC__)
178	int haveenv = 0;
179#endif
180	int havesearch = 0;
181#ifdef RESOLVSORT
182	int nsort = 0;
183#endif
184#if !defined(__BIONIC__)
185	char *net;
186#endif
187	int dots;
188	union res_sockaddr_union u[2];
189
190        if ((statp->options & RES_INIT) != 0U)
191                res_ndestroy(statp);
192
193	if (!preinit) {
194		statp->netid = NETID_UNSET;
195		statp->retrans = RES_TIMEOUT;
196		statp->retry = RES_DFLRETRY;
197		statp->options = RES_DEFAULT;
198		statp->id = res_randomid();
199		statp->_mark = MARK_UNSET;
200	}
201
202	memset(u, 0, sizeof(u));
203#ifdef USELOOPBACK
204	u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
205#else
206	u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
207#endif
208	u[nserv].sin.sin_family = AF_INET;
209	u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
210#ifdef HAVE_SA_LEN
211	u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
212#endif
213	nserv++;
214#ifdef HAS_INET6_STRUCTS
215#ifdef USELOOPBACK
216	u[nserv].sin6.sin6_addr = in6addr_loopback;
217#else
218	u[nserv].sin6.sin6_addr = in6addr_any;
219#endif
220	u[nserv].sin6.sin6_family = AF_INET6;
221	u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
222#ifdef HAVE_SA_LEN
223	u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
224#endif
225	nserv++;
226#endif
227	statp->nscount = 0;
228	statp->ndots = 1;
229	statp->pfcode = 0;
230	statp->_vcsock = -1;
231	statp->_flags = 0;
232	statp->qhook = NULL;
233	statp->rhook = NULL;
234	statp->_u._ext.nscount = 0;
235	statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
236	if (statp->_u._ext.ext != NULL) {
237	        memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
238		statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
239		strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
240		strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
241	}
242	statp->nsort = 0;
243	res_setservers(statp, u, nserv);
244
245#if defined(__BIONIC__)
246	/* Ignore the environment. */
247#else
248	/* Allow user to override the local domain definition */
249	if ((cp = getenv("LOCALDOMAIN")) != NULL) {
250		(void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
251		statp->defdname[sizeof(statp->defdname) - 1] = '\0';
252		haveenv++;
253
254		/*
255		 * Set search list to be blank-separated strings
256		 * from rest of env value.  Permits users of LOCALDOMAIN
257		 * to still have a search list, and anyone to set the
258		 * one that they want to use as an individual (even more
259		 * important now that the rfc1535 stuff restricts searches)
260		 */
261		cp = statp->defdname;
262		pp = statp->dnsrch;
263		*pp++ = cp;
264		for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
265			if (*cp == '\n')	/* silly backwards compat */
266				break;
267			else if (*cp == ' ' || *cp == '\t') {
268				*cp = 0;
269				n = 1;
270			} else if (n) {
271				*pp++ = cp;
272				n = 0;
273				havesearch = 1;
274			}
275		}
276		/* null terminate last domain if there are excess */
277		while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
278			cp++;
279		*cp = '\0';
280		*pp++ = 0;
281	}
282	if (nserv > 0)
283		statp->nscount = nserv;
284#endif
285
286#ifndef ANDROID_CHANGES /* !ANDROID_CHANGES - IGNORE resolv.conf in Android */
287#define	MATCH(line, name) \
288	(!strncmp(line, name, sizeof(name) - 1) && \
289	(line[sizeof(name) - 1] == ' ' || \
290	 line[sizeof(name) - 1] == '\t'))
291
292	nserv = 0;
293	if ((fp = fopen(_PATH_RESCONF, "re")) != NULL) {
294	    /* read the config file */
295	    while (fgets(buf, sizeof(buf), fp) != NULL) {
296		/* skip comments */
297		if (*buf == ';' || *buf == '#')
298			continue;
299		/* read default domain name */
300		if (MATCH(buf, "domain")) {
301		    if (haveenv)	/* skip if have from environ */
302			    continue;
303		    cp = buf + sizeof("domain") - 1;
304		    while (*cp == ' ' || *cp == '\t')
305			    cp++;
306		    if ((*cp == '\0') || (*cp == '\n'))
307			    continue;
308		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
309		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
310		    if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
311			    *cp = '\0';
312		    havesearch = 0;
313		    continue;
314		}
315		/* set search list */
316		if (MATCH(buf, "search")) {
317		    if (haveenv)	/* skip if have from environ */
318			    continue;
319		    cp = buf + sizeof("search") - 1;
320		    while (*cp == ' ' || *cp == '\t')
321			    cp++;
322		    if ((*cp == '\0') || (*cp == '\n'))
323			    continue;
324		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
325		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
326		    if ((cp = strchr(statp->defdname, '\n')) != NULL)
327			    *cp = '\0';
328		    /*
329		     * Set search list to be blank-separated strings
330		     * on rest of line.
331		     */
332		    cp = statp->defdname;
333		    pp = statp->dnsrch;
334		    *pp++ = cp;
335		    for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
336			    if (*cp == ' ' || *cp == '\t') {
337				    *cp = 0;
338				    n = 1;
339			    } else if (n) {
340				    *pp++ = cp;
341				    n = 0;
342			    }
343		    }
344		    /* null terminate last domain if there are excess */
345		    while (*cp != '\0' && *cp != ' ' && *cp != '\t')
346			    cp++;
347		    *cp = '\0';
348		    *pp++ = 0;
349		    havesearch = 1;
350		    continue;
351		}
352		/* read nameservers to query */
353		if (MATCH(buf, "nameserver") && nserv < MAXNS) {
354		    struct addrinfo hints, *ai;
355		    char sbuf[NI_MAXSERV];
356		    const size_t minsiz =
357		        sizeof(statp->_u._ext.ext->nsaddrs[0]);
358
359		    cp = buf + sizeof("nameserver") - 1;
360		    while (*cp == ' ' || *cp == '\t')
361			cp++;
362		    cp[strcspn(cp, ";# \t\n")] = '\0';
363		    if ((*cp != '\0') && (*cp != '\n')) {
364			memset(&hints, 0, sizeof(hints));
365			hints.ai_family = PF_UNSPEC;
366			hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
367			hints.ai_flags = AI_NUMERICHOST;
368			sprintf(sbuf, "%u", NAMESERVER_PORT);
369			if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
370			    ai->ai_addrlen <= minsiz) {
371			    if (statp->_u._ext.ext != NULL) {
372				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
373				    ai->ai_addr, ai->ai_addrlen);
374			    }
375			    if (ai->ai_addrlen <=
376			        sizeof(statp->nsaddr_list[nserv])) {
377				memcpy(&statp->nsaddr_list[nserv],
378				    ai->ai_addr, ai->ai_addrlen);
379			    } else
380				statp->nsaddr_list[nserv].sin_family = 0;
381			    freeaddrinfo(ai);
382			    nserv++;
383			}
384		    }
385		    continue;
386		}
387		if (MATCH(buf, "sortlist")) {
388		    struct in_addr a;
389
390		    cp = buf + sizeof("sortlist") - 1;
391		    while (nsort < MAXRESOLVSORT) {
392			while (*cp == ' ' || *cp == '\t')
393			    cp++;
394			if (*cp == '\0' || *cp == '\n' || *cp == ';')
395			    break;
396			net = cp;
397			while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
398			       isascii(*cp) && !isspace((unsigned char)*cp))
399				cp++;
400			n = *cp;
401			*cp = 0;
402			if (inet_aton(net, &a)) {
403			    statp->sort_list[nsort].addr = a;
404			    if (ISSORTMASK(n)) {
405				*cp++ = n;
406				net = cp;
407				while (*cp && *cp != ';' &&
408					isascii(*cp) &&
409					!isspace((unsigned char)*cp))
410				    cp++;
411				n = *cp;
412				*cp = 0;
413				if (inet_aton(net, &a)) {
414				    statp->sort_list[nsort].mask = a.s_addr;
415				} else {
416				    statp->sort_list[nsort].mask =
417					net_mask(statp->sort_list[nsort].addr);
418				}
419			    } else {
420				statp->sort_list[nsort].mask =
421				    net_mask(statp->sort_list[nsort].addr);
422			    }
423			    nsort++;
424			}
425			*cp = n;
426		    }
427		    continue;
428		}
429		if (MATCH(buf, "options")) {
430		    res_setoptions(statp, buf + sizeof("options") - 1, "conf");
431		    continue;
432		}
433	    }
434	    if (nserv > 0)
435		statp->nscount = nserv;
436	    statp->nsort = nsort;
437	    (void) fclose(fp);
438	}
439#endif /* !ANDROID_CHANGES */
440/*
441 * Last chance to get a nameserver.  This should not normally
442 * be necessary
443 */
444#ifdef NO_RESOLV_CONF
445	if(nserv == 0)
446		nserv = get_nameservers(statp);
447#endif
448
449	if (statp->defdname[0] == 0 &&
450	    gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
451	    (cp = strchr(buf, '.')) != NULL)
452		strcpy(statp->defdname, cp + 1);
453
454	/* find components of local domain that might be searched */
455	if (havesearch == 0) {
456		pp = statp->dnsrch;
457		*pp++ = statp->defdname;
458		*pp = NULL;
459
460		dots = 0;
461		for (cp = statp->defdname; *cp; cp++)
462			dots += (*cp == '.');
463
464		cp = statp->defdname;
465		while (pp < statp->dnsrch + MAXDFLSRCH) {
466			if (dots < LOCALDOMAINPARTS)
467				break;
468			cp = strchr(cp, '.') + 1;    /* we know there is one */
469			*pp++ = cp;
470			dots--;
471		}
472		*pp = NULL;
473#ifdef DEBUG
474		if (statp->options & RES_DEBUG) {
475			printf(";; res_init()... default dnsrch list:\n");
476			for (pp = statp->dnsrch; *pp; pp++)
477				printf(";;\t%s\n", *pp);
478			printf(";;\t..END..\n");
479		}
480#endif
481	}
482
483	if ((cp = getenv("RES_OPTIONS")) != NULL)
484		res_setoptions(statp, cp, "env");
485	if (nserv > 0) {
486		statp->nscount = nserv;
487		statp->options |= RES_INIT;
488	}
489	return (0);
490}
491
492static void
493res_setoptions(res_state statp, const char *options, const char *source)
494{
495	const char *cp = options;
496	int i;
497	struct __res_state_ext *ext = statp->_u._ext.ext;
498
499#ifdef DEBUG
500	if (statp->options & RES_DEBUG)
501		printf(";; res_setoptions(\"%s\", \"%s\")...\n",
502		       options, source);
503#endif
504	while (*cp) {
505		/* skip leading and inner runs of spaces */
506		while (*cp == ' ' || *cp == '\t')
507			cp++;
508		/* search for and process individual options */
509		if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
510			i = atoi(cp + sizeof("ndots:") - 1);
511			if (i <= RES_MAXNDOTS)
512				statp->ndots = i;
513			else
514				statp->ndots = RES_MAXNDOTS;
515#ifdef DEBUG
516			if (statp->options & RES_DEBUG)
517				printf(";;\tndots=%d\n", statp->ndots);
518#endif
519		} else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
520			i = atoi(cp + sizeof("timeout:") - 1);
521			if (i <= RES_MAXRETRANS)
522				statp->retrans = i;
523			else
524				statp->retrans = RES_MAXRETRANS;
525#ifdef DEBUG
526			if (statp->options & RES_DEBUG)
527				printf(";;\ttimeout=%d\n", statp->retrans);
528#endif
529		} else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
530			i = atoi(cp + sizeof("attempts:") - 1);
531			if (i <= RES_MAXRETRY)
532				statp->retry = i;
533			else
534				statp->retry = RES_MAXRETRY;
535#ifdef DEBUG
536			if (statp->options & RES_DEBUG)
537				printf(";;\tattempts=%d\n", statp->retry);
538#endif
539		} else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
540#ifdef DEBUG
541			if (!(statp->options & RES_DEBUG)) {
542				printf(";; res_setoptions(\"%s\", \"%s\")..\n",
543				       options, source);
544				statp->options |= RES_DEBUG;
545			}
546			printf(";;\tdebug\n");
547#endif
548		} else if (!strncmp(cp, "no_tld_query",
549				    sizeof("no_tld_query") - 1) ||
550			   !strncmp(cp, "no-tld-query",
551				    sizeof("no-tld-query") - 1)) {
552			statp->options |= RES_NOTLDQUERY;
553		} else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
554			statp->options |= RES_USE_INET6;
555		} else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
556			statp->options |= RES_ROTATE;
557		} else if (!strncmp(cp, "no-check-names",
558				    sizeof("no-check-names") - 1)) {
559			statp->options |= RES_NOCHECKNAME;
560		}
561#ifdef RES_USE_EDNS0
562		else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
563			statp->options |= RES_USE_EDNS0;
564		}
565#endif
566		else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
567			statp->options |= RES_USE_DNAME;
568		}
569		else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
570			if (ext == NULL)
571				goto skip;
572			cp += sizeof("nibble:") - 1;
573			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
574			strncpy(ext->nsuffix, cp, (size_t)i);
575			ext->nsuffix[i] = '\0';
576		}
577		else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
578			if (ext == NULL)
579				goto skip;
580			cp += sizeof("nibble2:") - 1;
581			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
582			strncpy(ext->nsuffix2, cp, (size_t)i);
583			ext->nsuffix2[i] = '\0';
584		}
585		else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
586			cp += sizeof("v6revmode:") - 1;
587			/* "nibble" and "bitstring" used to be valid */
588			if (!strncmp(cp, "single", sizeof("single") - 1)) {
589				statp->options |= RES_NO_NIBBLE2;
590			} else if (!strncmp(cp, "both", sizeof("both") - 1)) {
591				statp->options &=
592					 ~RES_NO_NIBBLE2;
593			}
594		}
595		else {
596			/* XXX - print a warning here? */
597		}
598   skip:
599		/* skip to next run of spaces */
600		while (*cp && *cp != ' ' && *cp != '\t')
601			cp++;
602	}
603}
604
605#ifdef RESOLVSORT
606/* XXX - should really support CIDR which means explicit masks always. */
607static uint32_t
608net_mask(struct in_addr in)	/*!< XXX - should really use system's version of this */
609{
610	register uint32_t i = ntohl(in.s_addr);
611
612	if (IN_CLASSA(i))
613		return (htonl(IN_CLASSA_NET));
614	else if (IN_CLASSB(i))
615		return (htonl(IN_CLASSB_NET));
616	return (htonl(IN_CLASSC_NET));
617}
618#endif
619
620/*%
621 * This routine is for closing the socket if a virtual circuit is used and
622 * the program wants to close it.  This provides support for endhostent()
623 * which expects to close the socket.
624 *
625 * This routine is not expected to be user visible.
626 */
627void
628res_nclose(res_state statp)
629{
630	int ns;
631
632	if (statp->_vcsock >= 0) {
633		(void) close(statp->_vcsock);
634		statp->_vcsock = -1;
635		statp->_flags &= ~(RES_F_VC | RES_F_CONN);
636	}
637	for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
638		if (statp->_u._ext.nssocks[ns] != -1) {
639			(void) close(statp->_u._ext.nssocks[ns]);
640			statp->_u._ext.nssocks[ns] = -1;
641		}
642	}
643}
644
645void
646res_ndestroy(res_state statp)
647{
648	res_nclose(statp);
649	if (statp->_u._ext.ext != NULL)
650		free(statp->_u._ext.ext);
651	statp->options &= ~RES_INIT;
652	statp->_u._ext.ext = NULL;
653}
654
655const char *
656res_get_nibblesuffix(res_state statp)
657{
658	if (statp->_u._ext.ext)
659		return (statp->_u._ext.ext->nsuffix);
660	return ("ip6.arpa");
661}
662
663const char *
664res_get_nibblesuffix2(res_state statp)
665{
666	if (statp->_u._ext.ext)
667		return (statp->_u._ext.ext->nsuffix2);
668	return ("ip6.int");
669}
670
671void
672res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt)
673{
674	int i, nserv;
675	size_t size;
676
677	/* close open servers */
678	res_nclose(statp);
679
680	/* cause rtt times to be forgotten */
681	statp->_u._ext.nscount = 0;
682
683	nserv = 0;
684	for (i = 0; i < cnt && nserv < MAXNS; i++) {
685		switch (set->sin.sin_family) {
686		case AF_INET:
687			size = sizeof(set->sin);
688			if (statp->_u._ext.ext)
689				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
690					&set->sin, size);
691			if (size <= sizeof(statp->nsaddr_list[nserv]))
692				memcpy(&statp->nsaddr_list[nserv],
693					&set->sin, size);
694			else
695				statp->nsaddr_list[nserv].sin_family = 0;
696			nserv++;
697			break;
698
699#ifdef HAS_INET6_STRUCTS
700		case AF_INET6:
701			size = sizeof(set->sin6);
702			if (statp->_u._ext.ext)
703				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
704					&set->sin6, size);
705			if (size <= sizeof(statp->nsaddr_list[nserv]))
706				memcpy(&statp->nsaddr_list[nserv],
707					&set->sin6, size);
708			else
709				statp->nsaddr_list[nserv].sin_family = 0;
710			nserv++;
711			break;
712#endif
713
714		default:
715			break;
716		}
717		set++;
718	}
719	statp->nscount = nserv;
720
721}
722
723int
724res_getservers(res_state statp, union res_sockaddr_union *set, int cnt)
725{
726	int i;
727	size_t size;
728	uint16_t family;
729
730	for (i = 0; i < statp->nscount && i < cnt; i++) {
731		if (statp->_u._ext.ext)
732			family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
733		else
734			family = statp->nsaddr_list[i].sin_family;
735
736		switch (family) {
737		case AF_INET:
738			size = sizeof(set->sin);
739			if (statp->_u._ext.ext)
740				memcpy(&set->sin,
741				       &statp->_u._ext.ext->nsaddrs[i],
742				       size);
743			else
744				memcpy(&set->sin, &statp->nsaddr_list[i],
745				       size);
746			break;
747
748#ifdef HAS_INET6_STRUCTS
749		case AF_INET6:
750			size = sizeof(set->sin6);
751			if (statp->_u._ext.ext)
752				memcpy(&set->sin6,
753				       &statp->_u._ext.ext->nsaddrs[i],
754				       size);
755			else
756				memcpy(&set->sin6, &statp->nsaddr_list[i],
757				       size);
758			break;
759#endif
760
761		default:
762			set->sin.sin_family = 0;
763			break;
764		}
765		set++;
766	}
767	return (statp->nscount);
768}
769
770#ifdef ANDROID_CHANGES
771void res_setnetcontext(res_state statp, const struct android_net_context *netcontext)
772{
773	if (statp != NULL) {
774		statp->netid = netcontext->dns_netid;
775		statp->_mark = netcontext->dns_mark;
776		statp->qhook = netcontext->qhook;
777		if (netcontext->flags & NET_CONTEXT_FLAG_USE_EDNS) {
778			statp->options |= RES_USE_EDNS0 | RES_USE_DNSSEC;
779		}
780	}
781}
782
783#endif /* ANDROID_CHANGES */
784