| /* | |
| * Copyright (c) 1985, 1989, 1993 | |
| * The Regents of the University of California. All rights reserved. | |
| * | |
| * Portions copyright (c) 1999, 2000 | |
| * Intel Corporation. | |
| * 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, Intel Corporation, and its contributors. | |
| * | |
| * 4. Neither the name of University, Intel Corporation, or their respective | |
| * 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, INTEL CORPORATION 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, | |
| * INTEL CORPORATION 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. | |
| * | |
| * 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 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 char sccsid[] = "@(#)res_init.c 8.1 (Berkeley) 6/7/93"; | |
| static char orig_rcsid[] = "From: Id: res_init.c,v 8.7 1996/11/18 09:10:04 vixie Exp $"; | |
| static char rcsid[] = "$Id: res_init.c,v 1.1.1.1 2003/11/19 01:51:37 kyu3 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 <resolv.h> | |
| #include <stdio.h> | |
| #include <stdlib.h> | |
| #include <string.h> | |
| #include <unistd.h> | |
| #include "res_config.h" | |
| static void res_setoptions __P((char *, char *)); | |
| #ifdef RESOLVSORT | |
| static const char sort_mask[] = "/&"; | |
| #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL) | |
| static u_int32_t net_mask __P((struct in_addr)); | |
| #endif | |
| #if !defined(isascii) /* XXX - could be a function */ | |
| # define isascii(c) (!(c & 0200)) | |
| #endif | |
| /* | |
| * Resolver state default settings. | |
| */ | |
| struct __res_state _res | |
| # if defined(__BIND_RES_TEXT) | |
| = { RES_TIMEOUT, } /* Motorola, et al. */ | |
| # endif | |
| ; | |
| /* | |
| * 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_init() | |
| { | |
| register FILE *fp; | |
| register char *cp, **pp; | |
| register int n; | |
| char buf[MAXDNAME]; | |
| int nserv = 0; /* number of nameserver records read from file */ | |
| int haveenv = 0; | |
| int havesearch = 0; | |
| #ifdef RESOLVSORT | |
| int nsort = 0; | |
| char *net; | |
| #endif | |
| #ifndef RFC1535 | |
| int dots; | |
| #endif | |
| /* | |
| * These three fields used to be statically initialized. This made | |
| * it hard to use this code in a shared library. It is necessary, | |
| * now that we're doing dynamic initialization here, that we preserve | |
| * the old semantics: if an application modifies one of these three | |
| * fields of _res before res_init() is called, res_init() will not | |
| * alter them. Of course, if an application is setting them to | |
| * _zero_ before calling res_init(), hoping to override what used | |
| * to be the static default, we can't detect it and unexpected results | |
| * will follow. Zero for any of these fields would make no sense, | |
| * so one can safely assume that the applications were already getting | |
| * unexpected results. | |
| * | |
| * _res.options is tricky since some apps were known to diddle the bits | |
| * before res_init() was first called. We can't replicate that semantic | |
| * with dynamic initialization (they may have turned bits off that are | |
| * set in RES_DEFAULT). Our solution is to declare such applications | |
| * "broken". They could fool us by setting RES_INIT but none do (yet). | |
| */ | |
| if (!_res.retrans) | |
| _res.retrans = RES_TIMEOUT; | |
| if (!_res.retry) | |
| _res.retry = 4; | |
| if (!(_res.options & RES_INIT)) | |
| _res.options = RES_DEFAULT; | |
| /* | |
| * This one used to initialize implicitly to zero, so unless the app | |
| * has set it to something in particular, we can randomize it now. | |
| */ | |
| if (!_res.id) | |
| _res.id = (u_short)res_randomid(); | |
| #ifdef USELOOPBACK | |
| _res.nsaddr.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1); | |
| #else | |
| _res.nsaddr.sin_addr.s_addr = INADDR_ANY; | |
| #endif | |
| _res.nsaddr.sin_family = AF_INET; | |
| _res.nsaddr.sin_port = htons(NAMESERVER_PORT); | |
| _res.nscount = 1; | |
| _res.ndots = 1; | |
| _res.pfcode = 0; | |
| /* Allow user to override the local domain definition */ | |
| #ifdef _ORG_FREEBSD_ | |
| if (issetugid() == 0 && (cp = getenv("LOCALDOMAIN")) != NULL) | |
| #else | |
| if ((cp = getenv("LOCALDOMAIN")) != NULL) | |
| #endif | |
| { | |
| (void)strncpy(_res.defdname, cp, sizeof(_res.defdname) - 1); | |
| _res.defdname[sizeof(_res.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 = _res.defdname; | |
| pp = _res.dnsrch; | |
| *pp++ = cp; | |
| for (n = 0; *cp && pp < _res.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, "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(_res.defdname, cp, sizeof(_res.defdname) - 1); | |
| _res.defdname[sizeof(_res.defdname) - 1] = '\0'; | |
| if ((cp = strpbrk(_res.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(_res.defdname, cp, sizeof(_res.defdname) - 1); | |
| _res.defdname[sizeof(_res.defdname) - 1] = '\0'; | |
| if ((cp = strchr(_res.defdname, '\n')) != NULL) | |
| *cp = '\0'; | |
| /* | |
| * Set search list to be blank-separated strings | |
| * on rest of line. | |
| */ | |
| cp = _res.defdname; | |
| pp = _res.dnsrch; | |
| *pp++ = cp; | |
| for (n = 0; *cp && pp < _res.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 in_addr a; | |
| cp = buf + sizeof("nameserver") - 1; | |
| while (*cp == ' ' || *cp == '\t') | |
| cp++; | |
| if ((*cp != '\0') && (*cp != '\n') && inet_aton(cp, &a)) { | |
| _res.nsaddr_list[nserv].sin_addr = a; | |
| _res.nsaddr_list[nserv].sin_family = AF_INET; | |
| _res.nsaddr_list[nserv].sin_port = | |
| htons(NAMESERVER_PORT); | |
| nserv++; | |
| } | |
| 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)) { | |
| _res.sort_list[nsort].addr = a; | |
| if (ISSORTMASK(n)) { | |
| *cp++ = (char)n; | |
| net = cp; | |
| while (*cp && *cp != ';' && | |
| isascii(*cp) && !isspace(*cp)) | |
| cp++; | |
| n = *cp; | |
| *cp = 0; | |
| if (inet_aton(net, &a)) { | |
| _res.sort_list[nsort].mask = a.s_addr; | |
| } else { | |
| _res.sort_list[nsort].mask = | |
| net_mask(_res.sort_list[nsort].addr); | |
| } | |
| } else { | |
| _res.sort_list[nsort].mask = | |
| net_mask(_res.sort_list[nsort].addr); | |
| } | |
| nsort++; | |
| } | |
| *cp = (char)n; | |
| } | |
| continue; | |
| } | |
| #endif | |
| if (MATCH(buf, "options")) { | |
| res_setoptions(buf + sizeof("options") - 1, "conf"); | |
| continue; | |
| } | |
| } | |
| if (nserv > 1) | |
| _res.nscount = nserv; | |
| #ifdef RESOLVSORT | |
| _res.nsort = nsort; | |
| #endif | |
| (void) fclose(fp); | |
| } | |
| if (_res.defdname[0] == 0 && | |
| gethostname(buf, sizeof(_res.defdname) - 1) == 0 && | |
| (cp = strchr(buf, '.')) != NULL) | |
| strcpy(_res.defdname, cp + 1); | |
| /* find components of local domain that might be searched */ | |
| if (havesearch == 0) { | |
| pp = _res.dnsrch; | |
| *pp++ = _res.defdname; | |
| *pp = NULL; | |
| #ifndef RFC1535 | |
| dots = 0; | |
| for (cp = _res.defdname; *cp; cp++) | |
| dots += (*cp == '.'); | |
| cp = _res.defdname; | |
| while (pp < _res.dnsrch + MAXDFLSRCH) { | |
| if (dots < LOCALDOMAINPARTS) | |
| break; | |
| cp = strchr(cp, '.') + 1; /* we know there is one */ | |
| *pp++ = cp; | |
| dots--; | |
| } | |
| *pp = NULL; | |
| #ifdef DEBUG | |
| if (_res.options & RES_DEBUG) { | |
| printf(";; res_init()... default dnsrch list:\n"); | |
| for (pp = _res.dnsrch; *pp; pp++) | |
| printf(";;\t%s\n", *pp); | |
| printf(";;\t..END..\n"); | |
| } | |
| #endif | |
| #endif /* !RFC1535 */ | |
| } | |
| #ifdef _ORG_FREEBSD_ | |
| if (issetugid()) | |
| #else | |
| if (1) | |
| #endif | |
| _res.options |= RES_NOALIASES; | |
| else if ((cp = getenv("RES_OPTIONS")) != NULL) | |
| res_setoptions(cp, "env"); | |
| _res.options |= RES_INIT; | |
| if ( 0 == nserv ) { | |
| return -1; | |
| } | |
| return (0); | |
| } | |
| static void | |
| res_setoptions( | |
| char *options, | |
| char *source | |
| ) | |
| { | |
| char *cp = options; | |
| int i; | |
| #ifdef DEBUG | |
| if (_res.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) | |
| _res.ndots = i; | |
| else | |
| _res.ndots = RES_MAXNDOTS; | |
| #ifdef DEBUG | |
| if (_res.options & RES_DEBUG) | |
| printf(";;\tndots=%d\n", _res.ndots); | |
| #endif | |
| } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) { | |
| #ifdef DEBUG | |
| if (!(_res.options & RES_DEBUG)) { | |
| printf(";; res_setoptions(\"%s\", \"%s\")..\n", | |
| options, source); | |
| _res.options |= RES_DEBUG; | |
| } | |
| printf(";;\tdebug\n"); | |
| #endif | |
| } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) { | |
| _res.options |= RES_USE_INET6; | |
| } else if (!strncmp(cp, "no_tld_query", sizeof("no_tld_query") - 1)) { | |
| _res.options |= RES_NOTLDQUERY; | |
| } 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( | |
| 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() | |
| { | |
| struct timeval now; | |
| gettimeofday(&now, NULL); | |
| return (0xffff & (now.tv_sec ^ now.tv_usec /* ^ getpid() */)); | |
| } |