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 <sys/system_properties.h>
103#endif /* ANDROID_CHANGES */
104
105#ifndef MIN
106#define	MIN(x,y)	((x)<(y)?(x):(y))
107#endif
108
109/* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */
110#ifdef ANDROID_CHANGES
111#include "resolv_private.h"
112#define MAX_DNS_PROPERTIES 8
113#define DNS_PROP_NAME_PREFIX "net.dns"
114#define DNS_CHANGE_PROP_NAME "net.dnschange"
115#define DNS_SEARCH_PROP_NAME "net.dns.search"
116static const prop_info *dns_change_prop;
117static int dns_last_change_counter;
118static int _get_dns_change_count();
119#else
120#include <resolv.h>
121#endif
122
123#include "res_private.h"
124
125/* Options.  Should all be left alone. */
126#ifndef DEBUG
127#define DEBUG
128#endif
129
130static void res_setoptions __P((res_state, const char *, const char *));
131
132static const char sort_mask[] = "/&";
133#define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
134static u_int32_t net_mask __P((struct in_addr));
135
136#if !defined(isascii)	/* XXX - could be a function */
137# define isascii(c) (!(c & 0200))
138#endif
139
140/*
141 * Resolver state default settings.
142 */
143
144/*
145 * Set up default settings.  If the configuration file exist, the values
146 * there will have precedence.  Otherwise, the server address is set to
147 * INADDR_ANY and the default domain name comes from the gethostname().
148 *
149 * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
150 * rather than INADDR_ANY ("0.0.0.0") as the default name server address
151 * since it was noted that INADDR_ANY actually meant ``the first interface
152 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
153 * it had to be "up" in order for you to reach your own name server.  It
154 * was later decided that since the recommended practice is to always
155 * install local static routes through 127.0.0.1 for all your network
156 * interfaces, that we could solve this problem without a code change.
157 *
158 * The configuration file should always be used, since it is the only way
159 * to specify a default domain.  If you are running a server on your local
160 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
161 * in the configuration file.
162 *
163 * Return 0 if completes successfully, -1 on error
164 */
165int
166res_ninit(res_state statp) {
167	extern int __res_vinit(res_state, int);
168
169	return (__res_vinit(statp, 0));
170}
171
172#ifdef ANDROID_CHANGES
173static int load_domain_search_list(res_state statp) {
174	char propvalue[PROP_VALUE_MAX];
175	register char *cp, **pp;
176
177	if(__system_property_get(DNS_SEARCH_PROP_NAME, propvalue) >= 1) {
178		strlcpy(statp->defdname, propvalue, sizeof(statp->defdname));
179		if ((cp = strchr(statp->defdname, '\n')) != NULL)
180			*cp = '\0';
181		cp = statp->defdname;
182		pp = statp->dnsrch;
183		while ( pp < statp->dnsrch + MAXDNSRCH ) {
184			while (*cp == ' ' || *cp == '\t') /* skip leading white space */
185				cp++;
186			if (*cp == '\0')  /* stop if nothing more */
187				break;
188			*pp++ = cp;  /* record this search domain */
189			while (*cp) { /* zero-terminate it */
190				if (*cp == ' ' || *cp == '\t') {
191					*cp++ = '\0';
192					break;
193				}
194				cp++;
195			}
196		}
197		*pp = NULL; /* statp->dnsrch has MAXDNSRCH+1 items */
198		if (pp > statp->dnsrch)
199			return 1;
200	}
201	statp->defdname[0] = '\0';  /* no default domain name on Android */
202	statp->dnsrch[0] = NULL;
203	return 0;
204}
205#endif
206
207/* This function has to be reachable by res_data.c but not publicly. */
208int
209__res_vinit(res_state statp, int preinit) {
210	register FILE *fp;
211	register char *cp, **pp;
212	register int n;
213	char buf[BUFSIZ];
214	int nserv = 0;    /* number of nameserver records read from file */
215	int haveenv = 0;
216	int havesearch = 0;
217	int nsort = 0;
218	char *net;
219	int dots;
220	union res_sockaddr_union u[2];
221#ifdef ANDROID_CHANGES
222        pid_t mypid = getpid();
223        int use_proc_props = 0;
224        int found_prop;
225	char dnsProperty[PROP_VALUE_MAX];
226#endif
227
228        if ((statp->options & RES_INIT) != 0U)
229                res_ndestroy(statp);
230
231	if (!preinit) {
232		statp->retrans = RES_TIMEOUT;
233		statp->retry = RES_DFLRETRY;
234		statp->options = RES_DEFAULT;
235		statp->id = res_randomid();
236	}
237
238	memset(u, 0, sizeof(u));
239#ifdef USELOOPBACK
240	u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
241#else
242	u[nserv].sin.sin_addr.s_addr = INADDR_ANY;
243#endif
244	u[nserv].sin.sin_family = AF_INET;
245	u[nserv].sin.sin_port = htons(NAMESERVER_PORT);
246#ifdef HAVE_SA_LEN
247	u[nserv].sin.sin_len = sizeof(struct sockaddr_in);
248#endif
249	nserv++;
250#ifdef HAS_INET6_STRUCTS
251#ifdef USELOOPBACK
252	u[nserv].sin6.sin6_addr = in6addr_loopback;
253#else
254	u[nserv].sin6.sin6_addr = in6addr_any;
255#endif
256	u[nserv].sin6.sin6_family = AF_INET6;
257	u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);
258#ifdef HAVE_SA_LEN
259	u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);
260#endif
261	nserv++;
262#endif
263	statp->nscount = 0;
264	statp->ndots = 1;
265	statp->pfcode = 0;
266	statp->_vcsock = -1;
267	statp->_flags = 0;
268	statp->qhook = NULL;
269	statp->rhook = NULL;
270	statp->_u._ext.nscount = 0;
271	statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));
272	if (statp->_u._ext.ext != NULL) {
273	        memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));
274		statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;
275		strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");
276		strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");
277	}
278	statp->nsort = 0;
279	res_setservers(statp, u, nserv);
280
281#if 0 /* IGNORE THE ENVIRONMENT */
282	/* Allow user to override the local domain definition */
283	if ((cp = getenv("LOCALDOMAIN")) != NULL) {
284		(void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
285		statp->defdname[sizeof(statp->defdname) - 1] = '\0';
286		haveenv++;
287
288		/*
289		 * Set search list to be blank-separated strings
290		 * from rest of env value.  Permits users of LOCALDOMAIN
291		 * to still have a search list, and anyone to set the
292		 * one that they want to use as an individual (even more
293		 * important now that the rfc1535 stuff restricts searches)
294		 */
295		cp = statp->defdname;
296		pp = statp->dnsrch;
297		*pp++ = cp;
298		for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
299			if (*cp == '\n')	/* silly backwards compat */
300				break;
301			else if (*cp == ' ' || *cp == '\t') {
302				*cp = 0;
303				n = 1;
304			} else if (n) {
305				*pp++ = cp;
306				n = 0;
307				havesearch = 1;
308			}
309		}
310		/* null terminate last domain if there are excess */
311		while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
312			cp++;
313		*cp = '\0';
314		*pp++ = 0;
315	}
316	if (nserv > 0)
317		statp->nscount = nserv;
318#endif
319#ifdef ANDROID_CHANGES /* READ FROM SYSTEM PROPERTIES */
320	dns_last_change_counter = _get_dns_change_count();
321
322	nserv = 0;
323	for(n = 1; n <= MAX_DNS_PROPERTIES && nserv < MAXNS; n++) {
324		char propname[PROP_NAME_MAX];
325		char propvalue[PROP_VALUE_MAX];
326
327		struct addrinfo hints, *ai;
328		char sbuf[NI_MAXSERV];
329		const size_t minsiz = sizeof(statp->_u._ext.ext->nsaddrs[0]);
330
331		/*
332		 * Check first for process-specific properties, and if those don't
333		 * exist, try the generic properties.
334		 */
335		found_prop = 0;
336		if (n == 1 || use_proc_props) {
337			snprintf(propname, sizeof(propname), "%s%d.%d", DNS_PROP_NAME_PREFIX, n, mypid);
338			if(__system_property_get(propname, propvalue) < 1) {
339				if (use_proc_props) {
340					break;
341				}
342			} else {
343				found_prop = 1;
344				use_proc_props = 1;
345			}
346		}
347		if (!found_prop) {
348			snprintf(propname, sizeof(propname), "%s%d", DNS_PROP_NAME_PREFIX, n);
349			if(__system_property_get(propname, propvalue) < 1) {
350				break;
351			}
352		}
353
354		cp = propvalue;
355
356		while (*cp == ' ' || *cp == '\t')
357			cp++;
358		cp[strcspn(cp, ";# \t\n")] = '\0';
359		if ((*cp != '\0') && (*cp != '\n')) {
360			memset(&hints, 0, sizeof(hints));
361			hints.ai_family = PF_UNSPEC;
362			hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
363			hints.ai_flags = AI_NUMERICHOST;
364			sprintf(sbuf, "%u", NAMESERVER_PORT);
365			if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
366			    (size_t)ai->ai_addrlen <= minsiz) {
367				if (statp->_u._ext.ext != NULL) {
368					memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
369					       ai->ai_addr, ai->ai_addrlen);
370				}
371				if ((size_t)ai->ai_addrlen <=
372				    sizeof(statp->nsaddr_list[nserv])) {
373					memcpy(&statp->nsaddr_list[nserv],
374					       ai->ai_addr, ai->ai_addrlen);
375				} else {
376					statp->nsaddr_list[nserv].sin_family = 0;
377				}
378				freeaddrinfo(ai);
379				nserv++;
380			}
381		}
382	}
383
384	/* Add the domain search list */
385	havesearch = load_domain_search_list(statp);
386#else /* !ANDROID_CHANGES - IGNORE resolv.conf in Android */
387#define	MATCH(line, name) \
388	(!strncmp(line, name, sizeof(name) - 1) && \
389	(line[sizeof(name) - 1] == ' ' || \
390	 line[sizeof(name) - 1] == '\t'))
391
392	nserv = 0;
393	if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
394	    /* read the config file */
395	    while (fgets(buf, sizeof(buf), fp) != NULL) {
396		/* skip comments */
397		if (*buf == ';' || *buf == '#')
398			continue;
399		/* read default domain name */
400		if (MATCH(buf, "domain")) {
401		    if (haveenv)	/* skip if have from environ */
402			    continue;
403		    cp = buf + sizeof("domain") - 1;
404		    while (*cp == ' ' || *cp == '\t')
405			    cp++;
406		    if ((*cp == '\0') || (*cp == '\n'))
407			    continue;
408		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
409		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
410		    if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
411			    *cp = '\0';
412		    havesearch = 0;
413		    continue;
414		}
415		/* set search list */
416		if (MATCH(buf, "search")) {
417		    if (haveenv)	/* skip if have from environ */
418			    continue;
419		    cp = buf + sizeof("search") - 1;
420		    while (*cp == ' ' || *cp == '\t')
421			    cp++;
422		    if ((*cp == '\0') || (*cp == '\n'))
423			    continue;
424		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
425		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';
426		    if ((cp = strchr(statp->defdname, '\n')) != NULL)
427			    *cp = '\0';
428		    /*
429		     * Set search list to be blank-separated strings
430		     * on rest of line.
431		     */
432		    cp = statp->defdname;
433		    pp = statp->dnsrch;
434		    *pp++ = cp;
435		    for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
436			    if (*cp == ' ' || *cp == '\t') {
437				    *cp = 0;
438				    n = 1;
439			    } else if (n) {
440				    *pp++ = cp;
441				    n = 0;
442			    }
443		    }
444		    /* null terminate last domain if there are excess */
445		    while (*cp != '\0' && *cp != ' ' && *cp != '\t')
446			    cp++;
447		    *cp = '\0';
448		    *pp++ = 0;
449		    havesearch = 1;
450		    continue;
451		}
452		/* read nameservers to query */
453		if (MATCH(buf, "nameserver") && nserv < MAXNS) {
454		    struct addrinfo hints, *ai;
455		    char sbuf[NI_MAXSERV];
456		    const size_t minsiz =
457		        sizeof(statp->_u._ext.ext->nsaddrs[0]);
458
459		    cp = buf + sizeof("nameserver") - 1;
460		    while (*cp == ' ' || *cp == '\t')
461			cp++;
462		    cp[strcspn(cp, ";# \t\n")] = '\0';
463		    if ((*cp != '\0') && (*cp != '\n')) {
464			memset(&hints, 0, sizeof(hints));
465			hints.ai_family = PF_UNSPEC;
466			hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
467			hints.ai_flags = AI_NUMERICHOST;
468			sprintf(sbuf, "%u", NAMESERVER_PORT);
469			if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&
470			    ai->ai_addrlen <= minsiz) {
471			    if (statp->_u._ext.ext != NULL) {
472				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
473				    ai->ai_addr, ai->ai_addrlen);
474			    }
475			    if (ai->ai_addrlen <=
476			        sizeof(statp->nsaddr_list[nserv])) {
477				memcpy(&statp->nsaddr_list[nserv],
478				    ai->ai_addr, ai->ai_addrlen);
479			    } else
480				statp->nsaddr_list[nserv].sin_family = 0;
481			    freeaddrinfo(ai);
482			    nserv++;
483			}
484		    }
485		    continue;
486		}
487		if (MATCH(buf, "sortlist")) {
488		    struct in_addr a;
489
490		    cp = buf + sizeof("sortlist") - 1;
491		    while (nsort < MAXRESOLVSORT) {
492			while (*cp == ' ' || *cp == '\t')
493			    cp++;
494			if (*cp == '\0' || *cp == '\n' || *cp == ';')
495			    break;
496			net = cp;
497			while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
498			       isascii(*cp) && !isspace((unsigned char)*cp))
499				cp++;
500			n = *cp;
501			*cp = 0;
502			if (inet_aton(net, &a)) {
503			    statp->sort_list[nsort].addr = a;
504			    if (ISSORTMASK(n)) {
505				*cp++ = n;
506				net = cp;
507				while (*cp && *cp != ';' &&
508					isascii(*cp) &&
509					!isspace((unsigned char)*cp))
510				    cp++;
511				n = *cp;
512				*cp = 0;
513				if (inet_aton(net, &a)) {
514				    statp->sort_list[nsort].mask = a.s_addr;
515				} else {
516				    statp->sort_list[nsort].mask =
517					net_mask(statp->sort_list[nsort].addr);
518				}
519			    } else {
520				statp->sort_list[nsort].mask =
521				    net_mask(statp->sort_list[nsort].addr);
522			    }
523			    nsort++;
524			}
525			*cp = n;
526		    }
527		    continue;
528		}
529		if (MATCH(buf, "options")) {
530		    res_setoptions(statp, buf + sizeof("options") - 1, "conf");
531		    continue;
532		}
533	    }
534	    if (nserv > 0)
535		statp->nscount = nserv;
536	    statp->nsort = nsort;
537	    (void) fclose(fp);
538	}
539#endif /* !ANDROID_CHANGES */
540/*
541 * Last chance to get a nameserver.  This should not normally
542 * be necessary
543 */
544#ifdef NO_RESOLV_CONF
545	if(nserv == 0)
546		nserv = get_nameservers(statp);
547#endif
548
549	if (statp->defdname[0] == 0 &&
550	    gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
551	    (cp = strchr(buf, '.')) != NULL)
552		strcpy(statp->defdname, cp + 1);
553
554	/* find components of local domain that might be searched */
555	if (havesearch == 0) {
556		pp = statp->dnsrch;
557		*pp++ = statp->defdname;
558		*pp = NULL;
559
560		dots = 0;
561		for (cp = statp->defdname; *cp; cp++)
562			dots += (*cp == '.');
563
564		cp = statp->defdname;
565		while (pp < statp->dnsrch + MAXDFLSRCH) {
566			if (dots < LOCALDOMAINPARTS)
567				break;
568			cp = strchr(cp, '.') + 1;    /* we know there is one */
569			*pp++ = cp;
570			dots--;
571		}
572		*pp = NULL;
573#ifdef DEBUG
574		if (statp->options & RES_DEBUG) {
575			printf(";; res_init()... default dnsrch list:\n");
576			for (pp = statp->dnsrch; *pp; pp++)
577				printf(";;\t%s\n", *pp);
578			printf(";;\t..END..\n");
579		}
580#endif
581	}
582
583	if ((cp = getenv("RES_OPTIONS")) != NULL)
584		res_setoptions(statp, cp, "env");
585	if (nserv > 0) {
586		statp->nscount = nserv;
587		statp->options |= RES_INIT;
588	}
589	return (0);
590}
591
592static void
593res_setoptions(res_state statp, const char *options, const char *source)
594{
595	const char *cp = options;
596	int i;
597	struct __res_state_ext *ext = statp->_u._ext.ext;
598
599#ifdef DEBUG
600	if (statp->options & RES_DEBUG)
601		printf(";; res_setoptions(\"%s\", \"%s\")...\n",
602		       options, source);
603#endif
604	while (*cp) {
605		/* skip leading and inner runs of spaces */
606		while (*cp == ' ' || *cp == '\t')
607			cp++;
608		/* search for and process individual options */
609		if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
610			i = atoi(cp + sizeof("ndots:") - 1);
611			if (i <= RES_MAXNDOTS)
612				statp->ndots = i;
613			else
614				statp->ndots = RES_MAXNDOTS;
615#ifdef DEBUG
616			if (statp->options & RES_DEBUG)
617				printf(";;\tndots=%d\n", statp->ndots);
618#endif
619		} else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
620			i = atoi(cp + sizeof("timeout:") - 1);
621			if (i <= RES_MAXRETRANS)
622				statp->retrans = i;
623			else
624				statp->retrans = RES_MAXRETRANS;
625#ifdef DEBUG
626			if (statp->options & RES_DEBUG)
627				printf(";;\ttimeout=%d\n", statp->retrans);
628#endif
629		} else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
630			i = atoi(cp + sizeof("attempts:") - 1);
631			if (i <= RES_MAXRETRY)
632				statp->retry = i;
633			else
634				statp->retry = RES_MAXRETRY;
635#ifdef DEBUG
636			if (statp->options & RES_DEBUG)
637				printf(";;\tattempts=%d\n", statp->retry);
638#endif
639		} else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
640#ifdef DEBUG
641			if (!(statp->options & RES_DEBUG)) {
642				printf(";; res_setoptions(\"%s\", \"%s\")..\n",
643				       options, source);
644				statp->options |= RES_DEBUG;
645			}
646			printf(";;\tdebug\n");
647#endif
648		} else if (!strncmp(cp, "no_tld_query",
649				    sizeof("no_tld_query") - 1) ||
650			   !strncmp(cp, "no-tld-query",
651				    sizeof("no-tld-query") - 1)) {
652			statp->options |= RES_NOTLDQUERY;
653		} else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
654			statp->options |= RES_USE_INET6;
655		} else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
656			statp->options |= RES_ROTATE;
657		} else if (!strncmp(cp, "no-check-names",
658				    sizeof("no-check-names") - 1)) {
659			statp->options |= RES_NOCHECKNAME;
660		}
661#ifdef RES_USE_EDNS0
662		else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {
663			statp->options |= RES_USE_EDNS0;
664		}
665#endif
666		else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {
667			statp->options |= RES_USE_DNAME;
668		}
669		else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {
670			if (ext == NULL)
671				goto skip;
672			cp += sizeof("nibble:") - 1;
673			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);
674			strncpy(ext->nsuffix, cp, (size_t)i);
675			ext->nsuffix[i] = '\0';
676		}
677		else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {
678			if (ext == NULL)
679				goto skip;
680			cp += sizeof("nibble2:") - 1;
681			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);
682			strncpy(ext->nsuffix2, cp, (size_t)i);
683			ext->nsuffix2[i] = '\0';
684		}
685		else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {
686			cp += sizeof("v6revmode:") - 1;
687			/* "nibble" and "bitstring" used to be valid */
688			if (!strncmp(cp, "single", sizeof("single") - 1)) {
689				statp->options |= RES_NO_NIBBLE2;
690			} else if (!strncmp(cp, "both", sizeof("both") - 1)) {
691				statp->options &=
692					 ~RES_NO_NIBBLE2;
693			}
694		}
695		else {
696			/* XXX - print a warning here? */
697		}
698   skip:
699		/* skip to next run of spaces */
700		while (*cp && *cp != ' ' && *cp != '\t')
701			cp++;
702	}
703}
704
705/* XXX - should really support CIDR which means explicit masks always. */
706static u_int32_t
707net_mask(in)		/* XXX - should really use system's version of this */
708	struct in_addr in;
709{
710	register u_int32_t i = ntohl(in.s_addr);
711
712	if (IN_CLASSA(i))
713		return (htonl(IN_CLASSA_NET));
714	else if (IN_CLASSB(i))
715		return (htonl(IN_CLASSB_NET));
716	return (htonl(IN_CLASSC_NET));
717}
718
719u_int
720res_randomid(void) {
721	struct timeval now;
722
723	gettimeofday(&now, NULL);
724	return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));
725}
726
727/*
728 * This routine is for closing the socket if a virtual circuit is used and
729 * the program wants to close it.  This provides support for endhostent()
730 * which expects to close the socket.
731 *
732 * This routine is not expected to be user visible.
733 */
734void
735res_nclose(res_state statp) {
736	int ns;
737
738	if (statp->_vcsock >= 0) {
739		(void) close(statp->_vcsock);
740		statp->_vcsock = -1;
741		statp->_flags &= ~(RES_F_VC | RES_F_CONN);
742	}
743	for (ns = 0; ns < statp->_u._ext.nscount; ns++) {
744		if (statp->_u._ext.nssocks[ns] != -1) {
745			(void) close(statp->_u._ext.nssocks[ns]);
746			statp->_u._ext.nssocks[ns] = -1;
747		}
748	}
749}
750
751void
752res_ndestroy(res_state statp) {
753	res_nclose(statp);
754	if (statp->_u._ext.ext != NULL)
755		free(statp->_u._ext.ext);
756	statp->options &= ~RES_INIT;
757	statp->_u._ext.ext = NULL;
758}
759
760const char *
761res_get_nibblesuffix(res_state statp) {
762	if (statp->_u._ext.ext)
763		return (statp->_u._ext.ext->nsuffix);
764	return ("ip6.arpa");
765}
766
767const char *
768res_get_nibblesuffix2(res_state statp) {
769	if (statp->_u._ext.ext)
770		return (statp->_u._ext.ext->nsuffix2);
771	return ("ip6.int");
772}
773
774void
775res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {
776	int i, nserv;
777	size_t size;
778
779	/* close open servers */
780	res_nclose(statp);
781
782	/* cause rtt times to be forgotten */
783	statp->_u._ext.nscount = 0;
784
785	nserv = 0;
786	for (i = 0; i < cnt && nserv < MAXNS; i++) {
787		switch (set->sin.sin_family) {
788		case AF_INET:
789			size = sizeof(set->sin);
790			if (statp->_u._ext.ext)
791				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
792					&set->sin, size);
793			if (size <= sizeof(statp->nsaddr_list[nserv]))
794				memcpy(&statp->nsaddr_list[nserv],
795					&set->sin, size);
796#ifdef notdef
797			else
798				statp->nsaddr_list[nserv].sin_family = 0;
799#endif
800			nserv++;
801			break;
802
803#ifdef HAS_INET6_STRUCTS
804		case AF_INET6:
805			size = sizeof(set->sin6);
806			if (statp->_u._ext.ext)
807				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],
808					&set->sin6, size);
809			if (size <= sizeof(statp->nsaddr_list[nserv]))
810				memcpy(&statp->nsaddr_list[nserv],
811					&set->sin6, size);
812			else
813				statp->nsaddr_list[nserv].sin_family = 0;
814			nserv++;
815			break;
816#endif
817
818		default:
819			break;
820		}
821		set++;
822	}
823	statp->nscount = nserv;
824
825}
826
827int
828res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {
829	int i;
830	size_t size;
831	u_int16_t family;
832
833	for (i = 0; i < statp->nscount && i < cnt; i++) {
834		if (statp->_u._ext.ext)
835			family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;
836		else
837			family = statp->nsaddr_list[i].sin_family;
838
839		switch (family) {
840		case AF_INET:
841			size = sizeof(set->sin);
842			if (statp->_u._ext.ext)
843				memcpy(&set->sin,
844				       &statp->_u._ext.ext->nsaddrs[i],
845				       size);
846			else
847				memcpy(&set->sin, &statp->nsaddr_list[i],
848				       size);
849			break;
850
851#ifdef HAS_INET6_STRUCTS
852		case AF_INET6:
853			size = sizeof(set->sin6);
854			if (statp->_u._ext.ext)
855				memcpy(&set->sin6,
856				       &statp->_u._ext.ext->nsaddrs[i],
857				       size);
858			else
859				memcpy(&set->sin6, &statp->nsaddr_list[i],
860				       size);
861			break;
862#endif
863
864		default:
865			set->sin.sin_family = 0;
866			break;
867		}
868		set++;
869	}
870	return (statp->nscount);
871}
872
873#ifdef ANDROID_CHANGES
874static int _get_dns_change_count()
875{
876	if (dns_change_prop == NULL) {
877		dns_change_prop = __system_property_find(DNS_CHANGE_PROP_NAME);
878	}
879	if (dns_change_prop != NULL) {
880		char propvalue[PROP_VALUE_MAX];
881		if (__system_property_read(dns_change_prop, NULL, propvalue) >= 1) {
882			return atoi(propvalue);
883		}
884	}
885	return -1;
886}
887
888int res_get_dns_changed()
889{
890	int change_count;
891
892	change_count = _get_dns_change_count();
893	if (change_count != dns_last_change_counter) {
894		if (change_count != -1) {
895			dns_last_change_counter = change_count;
896		}
897		return 1;
898	} else {
899		return 0;
900	}
901}
902#endif /* ANDROID_CHANGES */
903