The Tor Browser / file revision

 /*	$NetBSD: res_init.c,v 1.8 2006/03/19 03:10:08 christos Exp $	*/

 /*

  * Copyright (c) 1985, 1989, 1993

  *    The Regents of the University of California.  All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

  * are met:

  * 1. Redistributions of source code must retain the above copyright

  *    notice, this list of conditions and the following disclaimer.

  * 2. Redistributions in binary form must reproduce the above copyright

  *    notice, this list of conditions and the following disclaimer in the

  *    documentation and/or other materials provided with the distribution.

  * 3. All advertising materials mentioning features or use of this software

  *    must display the following acknowledgement:

  * 	This product includes software developed by the University of

  * 	California, Berkeley and its contributors.

  * 4. Neither the name of the University nor the names of its contributors

  *    may be used to endorse or promote products derived from this software

  *    without specific prior written permission.

  *

  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

  * SUCH DAMAGE.

  */

 /*

  * Portions Copyright (c) 1993 by Digital Equipment Corporation.

  *

  * Permission to use, copy, modify, and distribute this software for any

  * purpose with or without fee is hereby granted, provided that the above

  * copyright notice and this permission notice appear in all copies, and that

  * the name of Digital Equipment Corporation not be used in advertising or

  * publicity pertaining to distribution of the document or software without

  * specific, written prior permission.

  *

  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL

  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES

  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT

  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL

  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR

  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS

  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS

  * SOFTWARE.

  */

 /*

  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")

  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.

  *

  * Permission to use, copy, modify, and distribute this software for any

  * purpose with or without fee is hereby granted, provided that the above

  * copyright notice and this permission notice appear in all copies.

  *

  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES

  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR

  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT

  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

  */

 /*

  * This version of this file is derived from Android 2.3 "Gingerbread",

  * which contains uncredited changes by Android/Google developers.  It has

  * been modified in 2011 for use in the Android build of Mozilla Firefox by

  * Mozilla contributors (including Michael Edwards <m.k.edwards@gmail.com>,

  * and Steve Workman <sjhworkman@gmail.com>).

  * These changes are offered under the same license as the original NetBSD

  * file, whose copyright and license are unchanged above.

  */

 #define ANDROID_CHANGES 1

 #define MOZILLE_NECKO_EXCLUDE_CODE 1

 #include <sys/cdefs.h>

 #if defined(LIBC_SCCS) && !defined(lint)

 #ifdef notdef

 static const char sccsid[] = "@(#)res_init.c	8.1 (Berkeley) 6/7/93";

 static const char rcsid[] = "Id: res_init.c,v 1.9.2.5.4.2 2004/03/16 12:34:18 marka Exp";

 #else

 __RCSID("$NetBSD: res_init.c,v 1.8 2006/03/19 03:10:08 christos Exp $");

 #endif

 #endif /* LIBC_SCCS and not lint */

 #include <sys/types.h>

 #include <sys/param.h>

 #include <sys/socket.h>

 #include <sys/time.h>

 #include <netinet/in.h>

 #include <arpa/inet.h>

 #include "arpa_nameser.h"

 #include <ctype.h>

 #include <stdio.h>

 #include <stdlib.h>

 #include <string.h>

 #include <unistd.h>

 #include <netdb.h>

 #ifdef ANDROID_CHANGES

 #include <sys/system_properties.h>

 #endif /* ANDROID_CHANGES */

 #ifndef MIN

 #define	MIN(x,y)	((x)<(y)?(x):(y))

 #endif

 /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */

 #ifdef ANDROID_CHANGES

 #include "resolv_private.h"

 #define MAX_DNS_PROPERTIES 8

 #define DNS_PROP_NAME_PREFIX "net.dns"

 #define DNS_CHANGE_PROP_NAME "net.dnschange"

 #define DNS_SEARCH_PROP_NAME "net.dns.search"

 const prop_info *dns_change_prop;

 int dns_last_change_counter;

 static int _get_dns_change_count();

 #else

 #include <resolv.h>

 #endif

 #include "res_private.h"

 /* Options.  Should all be left alone. */

 #ifndef DEBUG

 #define DEBUG

 #endif

 static void res_setoptions __P((res_state, const char *, const char *));

 static const char sort_mask[] = "/&";

 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)

 static u_int32_t net_mask __P((struct in_addr));

 #if !defined(isascii)	/* XXX - could be a function */

 # define isascii(c) (!(c & 0200))

 #endif

 /*

  * Resolver state default settings.

  */

 /*

  * Set up default settings.  If the configuration file exist, the values

  * there will have precedence.  Otherwise, the server address is set to

  * INADDR_ANY and the default domain name comes from the gethostname().

  *

  * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1

  * rather than INADDR_ANY ("0.0.0.0") as the default name server address

  * since it was noted that INADDR_ANY actually meant ``the first interface

  * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,

  * it had to be "up" in order for you to reach your own name server.  It

  * was later decided that since the recommended practice is to always

  * install local static routes through 127.0.0.1 for all your network

  * interfaces, that we could solve this problem without a code change.

  *

  * The configuration file should always be used, since it is the only way

  * to specify a default domain.  If you are running a server on your local

  * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"

  * in the configuration file.

  *

  * Return 0 if completes successfully, -1 on error

  */

 int

 res_ninit(res_state statp) {

 	extern int __res_vinit(res_state, int);

 	return (__res_vinit(statp, 0));

 }

 #ifdef ANDROID_CHANGES

 int load_domain_search_list(res_state statp) {

 	char propvalue[PROP_VALUE_MAX];

 	register char *cp, **pp;

 	if(__system_property_get(DNS_SEARCH_PROP_NAME, propvalue) >= 1) {

 		strlcpy(statp->defdname, propvalue, sizeof(statp->defdname));

 		if ((cp = strchr(statp->defdname, '\n')) != NULL)

 			*cp = '\0';

 		cp = statp->defdname;

 		pp = statp->dnsrch;

 		while ( pp < statp->dnsrch + MAXDNSRCH ) {

 			while (*cp == ' ' || *cp == '\t') /* skip leading white space */

 				cp++;

 			if (*cp == '\0')  /* stop if nothing more */

 				break;

 			*pp++ = cp;  /* record this search domain */

 			while (*cp) { /* zero-terminate it */

 				if (*cp == ' ' || *cp == '\t') {

 					*cp++ = '\0';

 					break;

 				}

 				cp++;

 			}

 		}

 		*pp = NULL; /* statp->dnsrch has MAXDNSRCH+1 items */

 		if (pp > statp->dnsrch)

 			return 1;

 	}

 	statp->defdname[0] = '\0';  /* no default domain name on Android */

 	statp->dnsrch[0] = NULL;

 	return 0;

 }

 #endif

 /* This function has to be reachable by res_data.c but not publicly. */

 int

 __res_vinit(res_state statp, int preinit) {

 	register FILE *fp;

 	register char *cp, **pp;

 	register int n;

 	char buf[BUFSIZ];

 	int nserv = 0;    /* number of nameserver records read from file */

 	int haveenv = 0;

 	int havesearch = 0;

 	int nsort = 0;

 	char *net;

 	int dots;

 	union res_sockaddr_union u[2];

 #ifdef ANDROID_CHANGES

         pid_t mypid = getpid();

         int use_proc_props = 0;

         int found_prop;

 	char dnsProperty[PROP_VALUE_MAX];

 #endif

 	if (!preinit) {

 		statp->retrans = RES_TIMEOUT;

 		statp->retry = RES_DFLRETRY;

 		statp->options = RES_DEFAULT;

 		statp->id = res_randomid();

 	}

   if ((statp->options & RES_INIT) != 0U)

        res_ndestroy(statp);

 	memset(u, 0, sizeof(u));

 #ifdef USELOOPBACK

 	u[nserv].sin.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);

 #else

 	u[nserv].sin.sin_addr.s_addr = INADDR_ANY;

 #endif

 	u[nserv].sin.sin_family = AF_INET;

 	u[nserv].sin.sin_port = htons(NAMESERVER_PORT);

 #ifdef HAVE_SA_LEN

 	u[nserv].sin.sin_len = sizeof(struct sockaddr_in);

 #endif

 	nserv++;

 #ifdef HAS_INET6_STRUCTS

 #ifdef USELOOPBACK

 	u[nserv].sin6.sin6_addr = in6addr_loopback;

 #else

 	u[nserv].sin6.sin6_addr = in6addr_any;

 #endif

 	u[nserv].sin6.sin6_family = AF_INET6;

 	u[nserv].sin6.sin6_port = htons(NAMESERVER_PORT);

 #ifdef HAVE_SA_LEN

 	u[nserv].sin6.sin6_len = sizeof(struct sockaddr_in6);

 #endif

 	nserv++;

 #endif

 	statp->nscount = 0;

 	statp->ndots = 1;

 	statp->pfcode = 0;

 	statp->_vcsock = -1;

 	statp->_flags = 0;

 	statp->qhook = NULL;

 	statp->rhook = NULL;

 	statp->_u._ext.nscount = 0;

 	statp->_u._ext.ext = malloc(sizeof(*statp->_u._ext.ext));

 	if (statp->_u._ext.ext != NULL) {

 	        memset(statp->_u._ext.ext, 0, sizeof(*statp->_u._ext.ext));

 		statp->_u._ext.ext->nsaddrs[0].sin = statp->nsaddr;

 		strcpy(statp->_u._ext.ext->nsuffix, "ip6.arpa");

 		strcpy(statp->_u._ext.ext->nsuffix2, "ip6.int");

 	}

 	statp->nsort = 0;

 	res_setservers(statp, u, nserv);

 #if 0 /* IGNORE THE ENVIRONMENT */

 	/* Allow user to override the local domain definition */

 	if ((cp = getenv("LOCALDOMAIN")) != NULL) {

 		(void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);

 		statp->defdname[sizeof(statp->defdname) - 1] = '\0';

 		haveenv++;

 		/*

 		 * Set search list to be blank-separated strings

 		 * from rest of env value.  Permits users of LOCALDOMAIN

 		 * to still have a search list, and anyone to set the

 		 * one that they want to use as an individual (even more

 		 * important now that the rfc1535 stuff restricts searches)

 		 */

 		cp = statp->defdname;

 		pp = statp->dnsrch;

 		*pp++ = cp;

 		for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {

 			if (*cp == '\n')	/* silly backwards compat */

 				break;

 			else if (*cp == ' ' || *cp == '\t') {

 				*cp = 0;

 				n = 1;

 			} else if (n) {

 				*pp++ = cp;

 				n = 0;

 				havesearch = 1;

 			}

 		}

 		/* null terminate last domain if there are excess */

 		while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')

 			cp++;

 		*cp = '\0';

 		*pp++ = 0;

 	}

 	if (nserv > 0)

 		statp->nscount = nserv;

 #endif

 #ifdef ANDROID_CHANGES /* READ FROM SYSTEM PROPERTIES */

 	dns_last_change_counter = _get_dns_change_count();

 	nserv = 0;

 	for(n = 1; n <= MAX_DNS_PROPERTIES && nserv < MAXNS; n++) {

 		char propname[PROP_NAME_MAX];

 		char propvalue[PROP_VALUE_MAX];

 		struct addrinfo hints, *ai;

 		char sbuf[NI_MAXSERV];

 		const size_t minsiz = sizeof(statp->_u._ext.ext->nsaddrs[0]);

 		/*

 		 * Check first for process-specific properties, and if those don't

 		 * exist, try the generic properties.

 		 */

 		found_prop = 0;

 		if (n == 1 || use_proc_props) {

 			snprintf(propname, sizeof(propname), "%s%d.%d", DNS_PROP_NAME_PREFIX, n, mypid);

 			if(__system_property_get(propname, propvalue) < 1) {

 				if (use_proc_props) {

 					break;

 				}

 			} else {

 				found_prop = 1;

 				use_proc_props = 1;

 			}

 		}

 		if (!found_prop) {

 			snprintf(propname, sizeof(propname), "%s%d", DNS_PROP_NAME_PREFIX, n);

 			if(__system_property_get(propname, propvalue) < 1) {

 				break;

 			}

 		}

 		cp = propvalue;

 		while (*cp == ' ' || *cp == '\t')

 			cp++;

 		cp[strcspn(cp, ";# \t\n")] = '\0';

 		if ((*cp != '\0') && (*cp != '\n')) {

 			memset(&hints, 0, sizeof(hints));

 			hints.ai_family = PF_UNSPEC;

 			hints.ai_socktype = SOCK_DGRAM;	/*dummy*/

 			hints.ai_flags = AI_NUMERICHOST;

 			sprintf(sbuf, "%u", NAMESERVER_PORT);

 			if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&

 			    (size_t)ai->ai_addrlen <= minsiz) {

 				if (statp->_u._ext.ext != NULL) {

 					memcpy(&statp->_u._ext.ext->nsaddrs[nserv],

 					       ai->ai_addr, ai->ai_addrlen);

 				}

 				if ((size_t)ai->ai_addrlen <=

 				    sizeof(statp->nsaddr_list[nserv])) {

 					memcpy(&statp->nsaddr_list[nserv],

 					       ai->ai_addr, ai->ai_addrlen);

 				} else {

 					statp->nsaddr_list[nserv].sin_family = 0;

 				}

 				freeaddrinfo(ai);

 				nserv++;

 			}

 		}

 	}

 	/* Add the domain search list */

 	havesearch = load_domain_search_list(statp);

 #else /* !ANDROID_CHANGES - IGNORE resolv.conf in Android */

 #define	MATCH(line, name) \

 	(!strncmp(line, name, sizeof(name) - 1) && \

 	(line[sizeof(name) - 1] == ' ' || \

 	 line[sizeof(name) - 1] == '\t'))

 	nserv = 0;

 	if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {

 	    /* read the config file */

 	    while (fgets(buf, sizeof(buf), fp) != NULL) {

 		/* skip comments */

 		if (*buf == ';' || *buf == '#')

 			continue;

 		/* read default domain name */

 		if (MATCH(buf, "domain")) {

 		    if (haveenv)	/* skip if have from environ */

 			    continue;

 		    cp = buf + sizeof("domain") - 1;

 		    while (*cp == ' ' || *cp == '\t')

 			    cp++;

 		    if ((*cp == '\0') || (*cp == '\n'))

 			    continue;

 		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);

 		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';

 		    if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)

 			    *cp = '\0';

 		    havesearch = 0;

 		    continue;

 		}

 		/* set search list */

 		if (MATCH(buf, "search")) {

 		    if (haveenv)	/* skip if have from environ */

 			    continue;

 		    cp = buf + sizeof("search") - 1;

 		    while (*cp == ' ' || *cp == '\t')

 			    cp++;

 		    if ((*cp == '\0') || (*cp == '\n'))

 			    continue;

 		    strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);

 		    statp->defdname[sizeof(statp->defdname) - 1] = '\0';

 		    if ((cp = strchr(statp->defdname, '\n')) != NULL)

 			    *cp = '\0';

 		    /*

 		     * Set search list to be blank-separated strings

 		     * on rest of line.

 		     */

 		    cp = statp->defdname;

 		    pp = statp->dnsrch;

 		    *pp++ = cp;

 		    for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {

 			    if (*cp == ' ' || *cp == '\t') {

 				    *cp = 0;

 				    n = 1;

 			    } else if (n) {

 				    *pp++ = cp;

 				    n = 0;

 			    }

 		    }

 		    /* null terminate last domain if there are excess */

 		    while (*cp != '\0' && *cp != ' ' && *cp != '\t')

 			    cp++;

 		    *cp = '\0';

 		    *pp++ = 0;

 		    havesearch = 1;

 		    continue;

 		}

 		/* read nameservers to query */

 		if (MATCH(buf, "nameserver") && nserv < MAXNS) {

 		    struct addrinfo hints, *ai;

 		    char sbuf[NI_MAXSERV];

 		    const size_t minsiz =

 		        sizeof(statp->_u._ext.ext->nsaddrs[0]);

 		    cp = buf + sizeof("nameserver") - 1;

 		    while (*cp == ' ' || *cp == '\t')

 			cp++;

 		    cp[strcspn(cp, ";# \t\n")] = '\0';

 		    if ((*cp != '\0') && (*cp != '\n')) {

 			memset(&hints, 0, sizeof(hints));

 			hints.ai_family = PF_UNSPEC;

 			hints.ai_socktype = SOCK_DGRAM;	/*dummy*/

 			hints.ai_flags = AI_NUMERICHOST;

 			sprintf(sbuf, "%u", NAMESERVER_PORT);

 			if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 &&

 			    ai->ai_addrlen <= minsiz) {

 			    if (statp->_u._ext.ext != NULL) {

 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],

 				    ai->ai_addr, ai->ai_addrlen);

 			    }

 			    if (ai->ai_addrlen <=

 			        sizeof(statp->nsaddr_list[nserv])) {

 				memcpy(&statp->nsaddr_list[nserv],

 				    ai->ai_addr, ai->ai_addrlen);

 			    } else

 				statp->nsaddr_list[nserv].sin_family = 0;

 			    freeaddrinfo(ai);

 			    nserv++;

 			}

 		    }

 		    continue;

 		}

 		if (MATCH(buf, "sortlist")) {

 		    struct in_addr a;

 		    cp = buf + sizeof("sortlist") - 1;

 		    while (nsort < MAXRESOLVSORT) {

 			while (*cp == ' ' || *cp == '\t')

 			    cp++;

 			if (*cp == '\0' || *cp == '\n' || *cp == ';')

 			    break;

 			net = cp;

 			while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&

 			       isascii(*cp) && !isspace((unsigned char)*cp))

 				cp++;

 			n = *cp;

 			*cp = 0;

 			if (inet_aton(net, &a)) {

 			    statp->sort_list[nsort].addr = a;

 			    if (ISSORTMASK(n)) {

 				*cp++ = n;

 				net = cp;

 				while (*cp && *cp != ';' &&

 					isascii(*cp) &&

 					!isspace((unsigned char)*cp))

 				    cp++;

 				n = *cp;

 				*cp = 0;

 				if (inet_aton(net, &a)) {

 				    statp->sort_list[nsort].mask = a.s_addr;

 				} else {

 				    statp->sort_list[nsort].mask =

 					net_mask(statp->sort_list[nsort].addr);

 				}

 			    } else {

 				statp->sort_list[nsort].mask =

 				    net_mask(statp->sort_list[nsort].addr);

 			    }

 			    nsort++;

 			}

 			*cp = n;

 		    }

 		    continue;

 		}

 		if (MATCH(buf, "options")) {

 		    res_setoptions(statp, buf + sizeof("options") - 1, "conf");

 		    continue;

 		}

 	    }

 	    if (nserv > 0)

 		statp->nscount = nserv;

 	    statp->nsort = nsort;

 	    (void) fclose(fp);

 	}

 #endif /* !ANDROID_CHANGES */

 /*

  * Last chance to get a nameserver.  This should not normally

  * be necessary

  */

 #ifdef NO_RESOLV_CONF

 	if(nserv == 0)

 		nserv = get_nameservers(statp);

 #endif

 	if (statp->defdname[0] == 0 &&

 	    gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&

 	    (cp = strchr(buf, '.')) != NULL)

 		strcpy(statp->defdname, cp + 1);

 	/* find components of local domain that might be searched */

 	if (havesearch == 0) {

 		pp = statp->dnsrch;

 		*pp++ = statp->defdname;

 		*pp = NULL;

 		dots = 0;

 		for (cp = statp->defdname; *cp; cp++)

 			dots += (*cp == '.');

 		cp = statp->defdname;

 		while (pp < statp->dnsrch + MAXDFLSRCH) {

 			if (dots < LOCALDOMAINPARTS)

 				break;

 			cp = strchr(cp, '.') + 1;    /* we know there is one */

 			*pp++ = cp;

 			dots--;

 		}

 		*pp = NULL;

 #ifdef DEBUG

 		if (statp->options & RES_DEBUG) {

 			printf(";; res_init()... default dnsrch list:\n");

 			for (pp = statp->dnsrch; *pp; pp++)

 				printf(";;\t%s\n", *pp);

 			printf(";;\t..END..\n");

 		}

 #endif

 	}

 	if ((cp = getenv("RES_OPTIONS")) != NULL)

 		res_setoptions(statp, cp, "env");

 	if (nserv > 0) {

 		statp->nscount = nserv;

 		statp->options |= RES_INIT;

 	}

 	return (0);

 }

 static void

 res_setoptions(res_state statp, const char *options, const char *source)

 {

 	const char *cp = options;

 	int i;

 	struct __res_state_ext *ext = statp->_u._ext.ext;

 #ifdef DEBUG

 	if (statp->options & RES_DEBUG)

 		printf(";; res_setoptions(\"%s\", \"%s\")...\n",

 		       options, source);

 #endif

 	while (*cp) {

 		/* skip leading and inner runs of spaces */

 		while (*cp == ' ' || *cp == '\t')

 			cp++;

 		/* search for and process individual options */

 		if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {

 			i = atoi(cp + sizeof("ndots:") - 1);

 			if (i <= RES_MAXNDOTS)

 				statp->ndots = i;

 			else

 				statp->ndots = RES_MAXNDOTS;

 #ifdef DEBUG

 			if (statp->options & RES_DEBUG)

 				printf(";;\tndots=%d\n", statp->ndots);

 #endif

 		} else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {

 			i = atoi(cp + sizeof("timeout:") - 1);

 			if (i <= RES_MAXRETRANS)

 				statp->retrans = i;

 			else

 				statp->retrans = RES_MAXRETRANS;

 #ifdef DEBUG

 			if (statp->options & RES_DEBUG)

 				printf(";;\ttimeout=%d\n", statp->retrans);

 #endif

 		} else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){

 			i = atoi(cp + sizeof("attempts:") - 1);

 			if (i <= RES_MAXRETRY)

 				statp->retry = i;

 			else

 				statp->retry = RES_MAXRETRY;

 #ifdef DEBUG

 			if (statp->options & RES_DEBUG)

 				printf(";;\tattempts=%d\n", statp->retry);

 #endif

 		} else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {

 #ifdef DEBUG

 			if (!(statp->options & RES_DEBUG)) {

 				printf(";; res_setoptions(\"%s\", \"%s\")..\n",

 				       options, source);

 				statp->options |= RES_DEBUG;

 			}

 			printf(";;\tdebug\n");

 #endif

 		} else if (!strncmp(cp, "no_tld_query",

 				    sizeof("no_tld_query") - 1) ||

 			   !strncmp(cp, "no-tld-query",

 				    sizeof("no-tld-query") - 1)) {

 			statp->options |= RES_NOTLDQUERY;

 		} else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {

 			statp->options |= RES_USE_INET6;

 		} else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {

 			statp->options |= RES_ROTATE;

 		} else if (!strncmp(cp, "no-check-names",

 				    sizeof("no-check-names") - 1)) {

 			statp->options |= RES_NOCHECKNAME;

 		}

 #ifdef RES_USE_EDNS0

 		else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) {

 			statp->options |= RES_USE_EDNS0;

 		}

 #endif

 		else if (!strncmp(cp, "dname", sizeof("dname") - 1)) {

 			statp->options |= RES_USE_DNAME;

 		}

 		else if (!strncmp(cp, "nibble:", sizeof("nibble:") - 1)) {

 			if (ext == NULL)

 				goto skip;

 			cp += sizeof("nibble:") - 1;

 			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix) - 1);

 			strncpy(ext->nsuffix, cp, (size_t)i);

 			ext->nsuffix[i] = '\0';

 		}

 		else if (!strncmp(cp, "nibble2:", sizeof("nibble2:") - 1)) {

 			if (ext == NULL)

 				goto skip;

 			cp += sizeof("nibble2:") - 1;

 			i = MIN(strcspn(cp, " \t"), sizeof(ext->nsuffix2) - 1);

 			strncpy(ext->nsuffix2, cp, (size_t)i);

 			ext->nsuffix2[i] = '\0';

 		}

 		else if (!strncmp(cp, "v6revmode:", sizeof("v6revmode:") - 1)) {

 			cp += sizeof("v6revmode:") - 1;

 			/* "nibble" and "bitstring" used to be valid */

 			if (!strncmp(cp, "single", sizeof("single") - 1)) {

 				statp->options |= RES_NO_NIBBLE2;

 			} else if (!strncmp(cp, "both", sizeof("both") - 1)) {

 				statp->options &=

 					 ~RES_NO_NIBBLE2;

 			}

 		}

 		else {

 			/* XXX - print a warning here? */

 		}

    skip:

 		/* skip to next run of spaces */

 		while (*cp && *cp != ' ' && *cp != '\t')

 			cp++;

 	}

 }

 /* XXX - should really support CIDR which means explicit masks always. */

 static u_int32_t

 net_mask(in)		/* XXX - should really use system's version of this */

 	struct in_addr in;

 {

 	register u_int32_t i = ntohl(in.s_addr);

 	if (IN_CLASSA(i))

 		return (htonl(IN_CLASSA_NET));

 	else if (IN_CLASSB(i))

 		return (htonl(IN_CLASSB_NET));

 	return (htonl(IN_CLASSC_NET));

 }

 u_int

 res_randomid(void) {

 	struct timeval now;

 	gettimeofday(&now, NULL);

 	return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid()));

 }

 /*

  * This routine is for closing the socket if a virtual circuit is used and

  * the program wants to close it.  This provides support for endhostent()

  * which expects to close the socket.

  *

  * This routine is not expected to be user visible.

  */

 void

 res_nclose(res_state statp) {

 	int ns;

 	if (statp->_vcsock >= 0) {

 		(void) close(statp->_vcsock);

 		statp->_vcsock = -1;

 		statp->_flags &= ~(RES_F_VC | RES_F_CONN);

 	}

 	for (ns = 0; ns < statp->_u._ext.nscount; ns++) {

 		if (statp->_u._ext.nssocks[ns] != -1) {

 			(void) close(statp->_u._ext.nssocks[ns]);

 			statp->_u._ext.nssocks[ns] = -1;

 		}

 	}

 }

 void

 res_ndestroy(res_state statp) {

 	res_nclose(statp);

 	if (statp->_u._ext.ext != NULL)

 		free(statp->_u._ext.ext);

 	statp->options &= ~RES_INIT;

 	statp->_u._ext.ext = NULL;

 }

 const char *

 res_get_nibblesuffix(res_state statp) {

 	if (statp->_u._ext.ext)

 		return (statp->_u._ext.ext->nsuffix);

 	return ("ip6.arpa");

 }

 const char *

 res_get_nibblesuffix2(res_state statp) {

 	if (statp->_u._ext.ext)

 		return (statp->_u._ext.ext->nsuffix2);

 	return ("ip6.int");

 }

 void

 res_setservers(res_state statp, const union res_sockaddr_union *set, int cnt) {

 	int i, nserv;

 	size_t size;

 	/* close open servers */

 	res_nclose(statp);

 	/* cause rtt times to be forgotten */

 	statp->_u._ext.nscount = 0;

 	nserv = 0;

 	for (i = 0; i < cnt && nserv < MAXNS; i++) {

 		switch (set->sin.sin_family) {

 		case AF_INET:

 			size = sizeof(set->sin);

 			if (statp->_u._ext.ext)

 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],

 					&set->sin, size);

 			if (size <= sizeof(statp->nsaddr_list[nserv]))

 				memcpy(&statp->nsaddr_list[nserv],

 					&set->sin, size);

 #ifdef notdef

 			else

 				statp->nsaddr_list[nserv].sin_family = 0;

 #endif

 			nserv++;

 			break;

 #ifdef HAS_INET6_STRUCTS

 		case AF_INET6:

 			size = sizeof(set->sin6);

 			if (statp->_u._ext.ext)

 				memcpy(&statp->_u._ext.ext->nsaddrs[nserv],

 					&set->sin6, size);

 			if (size <= sizeof(statp->nsaddr_list[nserv]))

 				memcpy(&statp->nsaddr_list[nserv],

 					&set->sin6, size);

 			else

 				statp->nsaddr_list[nserv].sin_family = 0;

 			nserv++;

 			break;

 #endif

 		default:

 			break;

 		}

 		set++;

 	}

 	statp->nscount = nserv;

 }

 int

 res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) {

 	int i;

 	size_t size;

 	u_int16_t family;

 	for (i = 0; i < statp->nscount && i < cnt; i++) {

 		if (statp->_u._ext.ext)

 			family = statp->_u._ext.ext->nsaddrs[i].sin.sin_family;

 		else

 			family = statp->nsaddr_list[i].sin_family;

 		switch (family) {

 		case AF_INET:

 			size = sizeof(set->sin);

 			if (statp->_u._ext.ext)

 				memcpy(&set->sin,

 				       &statp->_u._ext.ext->nsaddrs[i],

 				       size);

 			else

 				memcpy(&set->sin, &statp->nsaddr_list[i],

 				       size);

 			break;

 #ifdef HAS_INET6_STRUCTS

 		case AF_INET6:

 			size = sizeof(set->sin6);

 			if (statp->_u._ext.ext)

 				memcpy(&set->sin6,

 				       &statp->_u._ext.ext->nsaddrs[i],

 				       size);

 			else

 				memcpy(&set->sin6, &statp->nsaddr_list[i],

 				       size);

 			break;

 #endif

 		default:

 			set->sin.sin_family = 0;

 			break;

 		}

 		set++;

 	}

 	return (statp->nscount);

 }

 #ifdef ANDROID_CHANGES

 static int _get_dns_change_count()

 {

 	if (dns_change_prop == NULL) {

 		dns_change_prop = __system_property_find(DNS_CHANGE_PROP_NAME);

 	}

 	if (dns_change_prop != NULL) {

 		char propvalue[PROP_VALUE_MAX];

 		if (__system_property_read(dns_change_prop, NULL, propvalue) >= 1) {

 			return atoi(propvalue);

 		}

 	}

 	return -1;

 }

 int res_get_dns_changed()

 {

 	int change_count;

 	change_count = _get_dns_change_count();

 	if (change_count != dns_last_change_counter) {

 		if (change_count != -1) {

 			dns_last_change_counter = change_count;

 		}

 		return 1;

 	} else {

 		return 0;

 	}

 }

 #endif /* ANDROID_CHANGES */