| /* |
| * 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. |
| * 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. |
| */ |
| |
| /* |
| * 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 INTERNET SOFTWARE CONSORTIUM DISCLAIMS |
| * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE |
| * CONSORTIUM 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. |
| */ |
| |
| #if defined(LIBC_SCCS) && !defined(lint) |
| static const char sccsid[] = "@(#)res_init.c 8.1 (Berkeley) 6/7/93"; |
| static const char rcsid[] = "$BINDId: res_init.c,v 8.16 2000/05/09 07:10:12 vixie Exp $"; |
| #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 <stdio_ext.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <unistd.h> |
| |
| #include <not-cancel.h> |
| #include "local.h" |
| #include <resolv.h> |
| |
| /* Options. Should all be left alone. */ |
| #define RESOLVSORT |
| #define RFC1535 |
| /* #undef DEBUG */ |
| |
| static void res_setoptions (res_state, const char *, const char *) |
| internal_function; |
| |
| #ifdef RESOLVSORT |
| static const char sort_mask_chars[] = "/&"; |
| #define ISSORTMASK(ch) (strchr(sort_mask_chars, ch) != NULL) |
| static u_int32_t net_mask (struct in_addr) __THROW; |
| #endif |
| |
| #if !defined(isascii) /* XXX - could be a function */ |
| # define isascii(c) (!(c & 0200)) |
| #endif |
| |
| #ifdef _LIBC |
| unsigned long long int __res_initstamp attribute_hidden; |
| #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 _LIBC |
| libc_hidden_def (__res_ninit) |
| #endif |
| |
| /* This function has to be reachable by res_data.c but not publically. */ |
| 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 */ |
| #ifdef _LIBC |
| int nservall = 0; /* number of NS records read, nserv IPv4 only */ |
| #endif |
| int haveenv = 0; |
| int havesearch = 0; |
| #ifdef RESOLVSORT |
| int nsort = 0; |
| char *net; |
| #endif |
| #ifndef RFC1535 |
| int dots; |
| #endif |
| #ifdef _LIBC |
| statp->_u._ext.initstamp = __res_initstamp; |
| #endif |
| |
| if (!preinit) { |
| statp->retrans = RES_TIMEOUT; |
| statp->retry = RES_DFLRETRY; |
| statp->options = RES_DEFAULT; |
| statp->id = res_randomid(); |
| } |
| |
| #ifdef USELOOPBACK |
| statp->nsaddr.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1); |
| #else |
| statp->nsaddr.sin_addr.s_addr = INADDR_ANY; |
| #endif |
| statp->nsaddr.sin_family = AF_INET; |
| statp->nsaddr.sin_port = htons(NAMESERVER_PORT); |
| statp->nscount = 1; |
| statp->ndots = 1; |
| statp->pfcode = 0; |
| statp->_vcsock = -1; |
| statp->_flags = 0; |
| statp->qhook = NULL; |
| statp->rhook = NULL; |
| statp->_u._ext.nsinit = 0; |
| statp->_u._ext.nscount = 0; |
| #ifdef _LIBC |
| statp->_u._ext.nscount6 = 0; |
| for (n = 0; n < MAXNS; n++) { |
| statp->_u._ext.nsaddrs[n] = NULL; |
| statp->_u._ext.nsmap[n] = MAXNS; |
| } |
| #endif |
| |
| /* 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; |
| } |
| |
| #define MATCH(line, name) \ |
| (!strncmp(line, name, sizeof(name) - 1) && \ |
| (line[sizeof(name) - 1] == ' ' || \ |
| line[sizeof(name) - 1] == '\t')) |
| |
| if ((fp = fopen(_PATH_RESCONF, "rc")) != NULL) { |
| /* No threads use this stream. */ |
| __fsetlocking (fp, FSETLOCKING_BYCALLER); |
| /* 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 */ |
| #ifdef _LIBC |
| if (MATCH(buf, "nameserver") && nservall < MAXNS) { |
| #else |
| if (MATCH(buf, "nameserver") && nserv < MAXNS) { |
| #endif |
| struct in_addr a; |
| |
| cp = buf + sizeof("nameserver") - 1; |
| while (*cp == ' ' || *cp == '\t') |
| cp++; |
| if ((*cp != '\0') && (*cp != '\n') |
| && inet_aton(cp, &a)) { |
| statp->nsaddr_list[nserv].sin_addr = a; |
| statp->nsaddr_list[nserv].sin_family = AF_INET; |
| statp->nsaddr_list[nserv].sin_port = |
| htons(NAMESERVER_PORT); |
| nserv++; |
| #ifdef _LIBC |
| nservall++; |
| } else { |
| struct in6_addr a6; |
| char *el; |
| |
| if ((el = strchr(cp, '\n')) != NULL) |
| *el = '\0'; |
| if ((*cp != '\0') && |
| (inet_pton(AF_INET6, cp, &a6) > 0)) { |
| struct sockaddr_in6 *sa6; |
| |
| sa6 = malloc(sizeof(*sa6)); |
| if (sa6 != NULL) { |
| sa6->sin6_addr = a6; |
| sa6->sin6_family = AF_INET6; |
| sa6->sin6_port = htons(NAMESERVER_PORT); |
| statp->_u._ext.nsaddrs[nservall] = sa6; |
| statp->_u._ext.nssocks[nservall] = -1; |
| statp->_u._ext.nsmap[nservall] = MAXNS + 1; |
| nservall++; |
| } |
| } |
| #endif |
| } |
| continue; |
| } |
| #ifdef RESOLVSORT |
| 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(*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(*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; |
| } |
| #endif |
| if (MATCH(buf, "options")) { |
| res_setoptions(statp, buf + sizeof("options") - 1, "conf"); |
| continue; |
| } |
| } |
| if (nserv > 1) |
| statp->nscount = nserv; |
| #ifdef _LIBC |
| if (nservall - nserv > 0) |
| statp->_u._ext.nscount6 = nservall - nserv; |
| #endif |
| #ifdef RESOLVSORT |
| statp->nsort = nsort; |
| #endif |
| (void) fclose(fp); |
| } |
| 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; |
| |
| #ifndef RFC1535 |
| dots = 0; |
| for (cp = statp->defdname; *cp; cp++) |
| dots += (*cp == '.'); |
| |
| cp = statp->defdname; |
| while (pp < statp->dnsrch + MAXDFLSRCH) { |
| if (dots < LOCALDOMAINPARTS) |
| break; |
| cp = memchr(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 |
| #endif /* !RFC1535 */ |
| } |
| |
| if ((cp = getenv("RES_OPTIONS")) != NULL) |
| res_setoptions(statp, cp, "env"); |
| statp->options |= RES_INIT; |
| return (0); |
| } |
| |
| static void |
| internal_function |
| res_setoptions(res_state statp, const char *options, const char *source) { |
| const char *cp = options; |
| int i; |
| |
| #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; |
| } 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; |
| } 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, "inet6", sizeof("inet6") - 1)) { |
| statp->options |= RES_USE_INET6; |
| } else if (!strncmp(cp, "ip6-bytestring", |
| sizeof("ip6-bytestring") - 1)) { |
| statp->options |= RES_USEBSTRING; |
| } else if (!strncmp(cp, "no-ip6-dotint", |
| sizeof("no-ip6-dotint") - 1)) { |
| statp->options |= RES_NOIP6DOTINT; |
| } else if (!strncmp(cp, "ip6-dotint", |
| sizeof("ip6-dotint") - 1)) { |
| statp->options &= ~RES_NOIP6DOTINT; |
| } 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; |
| } else { |
| /* XXX - print a warning here? */ |
| } |
| /* skip to next run of spaces */ |
| while (*cp && *cp != ' ' && *cp != '\t') |
| cp++; |
| } |
| } |
| |
| #ifdef RESOLVSORT |
| /* 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)); |
| } |
| #endif |
| |
| u_int |
| res_randomid(void) { |
| struct timeval now; |
| |
| gettimeofday(&now, NULL); |
| return (0xffff & (now.tv_sec ^ now.tv_usec ^ getpid())); |
| } |
| #ifdef _LIBC |
| libc_hidden_def (__res_randomid) |
| #endif |
| |
| |
| /* |
| * 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) { |
| close_not_cancel_no_status(statp->_vcsock); |
| statp->_vcsock = -1; |
| statp->_flags &= ~(RES_F_VC | RES_F_CONN); |
| } |
| #ifdef _LIBC |
| for (ns = 0; ns < MAXNS; ns++) |
| #else |
| for (ns = 0; ns < statp->_u._ext.nscount; ns++) |
| #endif |
| if (statp->_u._ext.nsaddrs[ns] |
| && statp->_u._ext.nssocks[ns] != -1) { |
| close_not_cancel_no_status(statp->_u._ext.nssocks[ns]); |
| statp->_u._ext.nssocks[ns] = -1; |
| } |
| statp->_u._ext.nsinit = 0; |
| } |
| #ifdef _LIBC |
| libc_hidden_def (__res_nclose) |
| #endif |
| |
| #ifdef _LIBC |
| # ifdef _LIBC_REENTRANT |
| /* This is called when a thread is exiting to free resources held in _res. */ |
| static void __attribute__ ((section ("__libc_thread_freeres_fn"))) |
| res_thread_freeres (void) |
| { |
| if (_res.nscount == 0) |
| /* Never called res_ninit. */ |
| return; |
| |
| __res_nclose (&_res); /* Close any VC sockets. */ |
| |
| for (int ns = 0; ns < MAXNS; ns++) |
| if (_res._u._ext.nsaddrs[ns] != NULL) |
| { |
| free (_res._u._ext.nsaddrs[ns]); |
| _res._u._ext.nsaddrs[ns] = NULL; |
| } |
| |
| /* Make sure we do a full re-initialization the next time. */ |
| _res.options = 0; |
| } |
| text_set_element (__libc_thread_subfreeres, res_thread_freeres); |
| text_set_element (__libc_subfreeres, res_thread_freeres); |
| # endif |
| #endif |