/* $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.
*/
#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 <errno.h>
#include <fcntl.h>
#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"
static const prop_info *dns_change_prop;
static 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
static 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 ((statp->options & RES_INIT) != 0U)
res_ndestroy(statp);
if (!preinit) {
statp->retrans = RES_TIMEOUT;
statp->retry = RES_DFLRETRY;
statp->options = RES_DEFAULT;
statp->id = res_randomid();
}
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));
}
#ifdef ANDROID_CHANGES
static int
real_randomid(u_int *random_value) {
/* open the nonblocking random device, returning -1 on failure */
int random_device = open("/dev/urandom", O_RDONLY);
if (random_device < 0) {
return -1;
}
/* read from the random device, returning -1 on failure (or too many retries)*/
u_int retry = 5;
for (retry; retry > 0; retry--) {
int retval = read(random_device, random_value, sizeof(u_int));
if (retval == sizeof(u_int)) {
*random_value &= 0xffff;
close(random_device);
return 0;
} else if ((retval < 0) && (errno != EINTR)) {
break;
}
}
close(random_device);
return -1;
}
#endif /* ANDROID_CHANGES */
u_int
res_randomid(void) {
#ifdef ANDROID_CHANGES
int status = 0;
u_int output = 0;
status = real_randomid(&output);
if (status != -1) {
return output;
}
#endif /* ANDROID_CHANGES */
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 */