/** $MirOS: src/lib/libc/net/res_init.c,v 1.4 2005/09/22 20:40:03 tg Exp $ */ /* $OpenBSD: res_init.c,v 1.33 2005/08/06 20:30:04 espie 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. 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. */ #ifndef INET6 #define INET6 #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #endif /* INET6 */ #include "thread_private.h" __RCSID("$MirOS: src/lib/libc/net/res_init.c,v 1.4 2005/09/22 20:40:03 tg Exp $"); /*-------------------------------------- info about "sortlist" -------------- * Marc Majka 1994/04/16 * Allan Nathanson 1994/10/29 (BIND 4.9.3.x) * * NetInfo resolver configuration directory support. * * Allow a NetInfo directory to be created in the hierarchy which * contains the same information as the resolver configuration file. * * - The local domain name is stored as the value of the "domain" property. * - The Internet address(es) of the name server(s) are stored as values * of the "nameserver" property. * - The name server addresses are stored as values of the "nameserver" * property. * - The search list for host-name lookup is stored as values of the * "search" property. * - The sortlist comprised of IP address netmask pairs are stored as * values of the "sortlist" property. The IP address and optional netmask * should be separated by a slash (/) or ampersand (&) character. * - Internal resolver variables can be set from the value of the "options" * property. */ static void res_setoptions(char *, char *); #ifdef RESOLVSORT static const char sort_mask[] = "/&"; #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL) static u_int32_t net_mask(struct in_addr); #endif /* * Resolver state default settings. */ void *__THREAD_NAME(_res); struct __res_state _res # if defined(__BIND_RES_TEXT) = { RES_TIMEOUT, } /* Motorola, et al. */ # endif ; #ifdef INET6 void *__THREAD_NAME(_res_ext); struct __res_state_ext _res_ext; #endif /* INET6 */ int __res_chktime = 30; /* * 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(void) { return (_res_init(1)); } int _res_init(int usercall) { struct stat sb; struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res); #ifdef INET6 struct __res_state_ext *_res_extp = _THREAD_PRIVATE(_res_ext, _res_ext, &_res_ext); #endif FILE *fp; char *cp, **pp; int n; char buf[BUFSIZ]; int nserv = 0; /* number of nameserver records read from file */ int haveenv = 0; int havesearch = 0; size_t len; #ifdef RESOLVSORT int nsort = 0; char *net; #endif #ifndef RFC1535 int dots; #endif if (usercall == 0) { if (_resp->options & RES_INIT && _resp->reschktime >= time(NULL)) return (0); _resp->reschktime = time(NULL) + __res_chktime; if (stat(_PATH_RESCONF, &sb) != -1) { if (timespeccmp(&sb.st_mtimespec, &_resp->restimespec, ==)) return (0); else _resp->restimespec = sb.st_mtimespec; } else { /* * Lost the file, in chroot? * Don' trash settings */ if (timespecisset(&_resp->restimespec)) return (0); } } else _resp->reschktime = time(NULL) + __res_chktime; /* * 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 (!_resp->retrans) _resp->retrans = RES_TIMEOUT; if (!_resp->retry) _resp->retry = 4; if (!(_resp->options & RES_INIT)) _resp->options = RES_DEFAULT; #ifdef USELOOPBACK _resp->nsaddr.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1); #else _resp->nsaddr.sin_addr.s_addr = INADDR_ANY; #endif _resp->nsaddr.sin_family = AF_INET; _resp->nsaddr.sin_port = htons(NAMESERVER_PORT); _resp->nsaddr.sin_len = sizeof(struct sockaddr_in); #ifdef INET6 if (sizeof(_res_extp->nsaddr) >= sizeof(struct sockaddr_in)) memcpy(&_res_extp->nsaddr, &_resp->nsaddr, sizeof(struct sockaddr_in)); #endif _resp->nscount = 1; _resp->ndots = 1; _resp->pfcode = 0; strlcpy(_resp->lookups, "f", sizeof _resp->lookups); /* Allow user to override the local domain definition */ if (issetugid() == 0 && (cp = getenv("LOCALDOMAIN")) != NULL) { strlcpy(_resp->defdname, cp, sizeof(_resp->defdname)); 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 = _resp->defdname; pp = _resp->dnsrch; *pp++ = cp; for (n = 0; *cp && pp < _resp->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) { strlcpy(_resp->lookups, "bf", sizeof _resp->lookups); /* read the config file */ buf[0] = '\0'; while ((cp = fgetln(fp, &len)) != NULL) { /* skip lines that are too long or zero length */ if (len >= sizeof(buf) || len == 0) continue; (void)memcpy(buf, cp, len); buf[len] = '\0'; /* skip comments */ if ((cp = strpbrk(buf, ";#")) != NULL) *cp = '\0'; if (buf[0] == '\0') 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; strlcpy(_resp->defdname, cp, sizeof(_resp->defdname)); if ((cp = strpbrk(_resp->defdname, " \t\n")) != NULL) *cp = '\0'; havesearch = 0; continue; } /* lookup types */ if (MATCH(buf, "lookup")) { char *sp = NULL; memset(_resp->lookups, 0, sizeof _resp->lookups); cp = buf + sizeof("lookup") - 1; for (n = 0;; cp++) { if (n == MAXDNSLUS) break; if ((*cp == '\0') || (*cp == '\n')) { if (sp) { if (*sp=='y' || *sp=='b' || *sp=='f') _resp->lookups[n++] = *sp; sp = NULL; } break; } else if ((*cp == ' ') || (*cp == '\t') || (*cp == ',')) { if (sp) { if (*sp=='y' || *sp=='b' || *sp=='f') _resp->lookups[n++] = *sp; sp = NULL; } } else if (sp == NULL) sp = cp; } 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; strlcpy(_resp->defdname, cp, sizeof(_resp->defdname)); if ((cp = strchr(_resp->defdname, '\n')) != NULL) *cp = '\0'; /* * Set search list to be blank-separated strings * on rest of line. */ cp = _resp->defdname; pp = _resp->dnsrch; *pp++ = cp; for (n = 0; *cp && pp < _resp->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) { #ifdef INET6 char *q; struct addrinfo hints, *res; char pbuf[NI_MAXSERV]; #else struct in_addr a; #endif /* INET6 */ cp = buf + sizeof("nameserver") - 1; while (*cp == ' ' || *cp == '\t') cp++; #ifdef INET6 if ((*cp == '\0') || (*cp == '\n')) continue; for (q = cp; *q; q++) { if (isspace(*q)) { *q = '\0'; break; } } memset(&hints, 0, sizeof(hints)); hints.ai_flags = AI_NUMERICHOST; hints.ai_socktype = SOCK_DGRAM; snprintf(pbuf, sizeof(pbuf), "%u", NAMESERVER_PORT); res = NULL; if (getaddrinfo(cp, pbuf, &hints, &res) == 0 && res->ai_next == NULL) { if (res->ai_addrlen <= sizeof(_res_extp->nsaddr_list[nserv])) { memcpy(&_res_extp->nsaddr_list[nserv], res->ai_addr, res->ai_addrlen); } else { memset(&_res_extp->nsaddr_list[nserv], 0, sizeof(_res_extp->nsaddr_list[nserv])); } if (res->ai_addrlen <= sizeof(_resp->nsaddr_list[nserv])) { memcpy(&_resp->nsaddr_list[nserv], res->ai_addr, res->ai_addrlen); } else { memset(&_resp->nsaddr_list[nserv], 0, sizeof(_resp->nsaddr_list[nserv])); } nserv++; } if (res) freeaddrinfo(res); #else /* INET6 */ if ((*cp != '\0') && (*cp != '\n') && inet_aton(cp, &a)) { _resp->nsaddr_list[nserv].sin_addr = a; _resp->nsaddr_list[nserv].sin_family = AF_INET; _resp->nsaddr_list[nserv].sin_port = htons(NAMESERVER_PORT); _resp->nsaddr_list[nserv].sin_len = sizeof(struct sockaddr_in); nserv++; } #endif /* INET6 */ continue; } #ifdef RESOLVSORT if (MATCH(buf, "sortlist")) { struct in_addr a; #ifdef INET6 struct in6_addr a6; int m, i; u_char *u; #endif /* INET6 */ 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)) { _resp->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)) { _resp->sort_list[nsort].mask = a.s_addr; } else { _resp->sort_list[nsort].mask = net_mask(_resp->sort_list[nsort].addr); } } else { _resp->sort_list[nsort].mask = net_mask(_resp->sort_list[nsort].addr); } #ifdef INET6 _res_extp->sort_list[nsort].af = AF_INET; _res_extp->sort_list[nsort].addr.ina = _resp->sort_list[nsort].addr; _res_extp->sort_list[nsort].mask.ina.s_addr = _resp->sort_list[nsort].mask; #endif /* INET6 */ nsort++; } #ifdef INET6 else if (inet_pton(AF_INET6, net, &a6) == 1) { _res_extp->sort_list[nsort].af = AF_INET6; _res_extp->sort_list[nsort].addr.in6a = a6; u = (u_char *)&_res_extp->sort_list[nsort].mask.in6a; *cp++ = n; net = cp; while (*cp && *cp != ';' && isascii(*cp) && !isspace(*cp)) cp++; m = n; n = *cp; *cp = 0; switch (m) { case '/': m = atoi(net); break; case '&': if (inet_pton(AF_INET6, net, u) == 1) { m = -1; break; } /*FALLTHRU*/ default: m = sizeof(struct in6_addr) * NBBY; break; } if (m >= 0) { for (i = 0; i < sizeof(struct in6_addr); i++) { if (m <= 0) { *u = 0; } else { m -= NBBY; *u = (u_char)~0; if (m < 0) *u <<= -m; } u++; } } nsort++; } #endif /* INET6 */ *cp = n; } continue; } #endif if (MATCH(buf, "options")) { res_setoptions(buf + sizeof("options") - 1, "conf"); continue; } } if (nserv > 1) _resp->nscount = nserv; #ifdef RESOLVSORT _resp->nsort = nsort; #endif (void) fclose(fp); } if (_resp->defdname[0] == 0 && gethostname(buf, sizeof(_resp->defdname) - 1) == 0 && (cp = strchr(buf, '.')) != NULL) { strlcpy(_resp->defdname, cp + 1, sizeof(_resp->defdname)); } /* find components of local domain that might be searched */ if (havesearch == 0) { pp = _resp->dnsrch; *pp++ = _resp->defdname; *pp = NULL; #ifndef RFC1535 dots = 0; for (cp = _resp->defdname; *cp; cp++) dots += (*cp == '.'); cp = _resp->defdname; while (pp < _resp->dnsrch + MAXDFLSRCH) { if (dots < LOCALDOMAINPARTS) break; cp = strchr(cp, '.') + 1; /* we know there is one */ *pp++ = cp; dots--; } *pp = NULL; #ifdef DEBUG if (_resp->options & RES_DEBUG) { printf(";; res_init()... default dnsrch list:\n"); for (pp = _resp->dnsrch; *pp; pp++) printf(";;\t%s\n", *pp); printf(";;\t..END..\n"); } #endif /* DEBUG */ #endif /* !RFC1535 */ } if (issetugid()) _resp->options |= RES_NOALIASES; else if ((cp = getenv("RES_OPTIONS")) != NULL) res_setoptions(cp, "env"); _resp->options |= RES_INIT; return (0); } /* ARGSUSED */ static void res_setoptions(char *options, char *source) { struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res); char *cp = options; char *endp; long l; #ifdef DEBUG if (_resp->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)) { char *p = cp + sizeof("ndots:") - 1; l = strtol(p, &endp, 10); if (l >= 0 && endp != p && (*endp = '\0' || isspace(*endp))) { if (l <= RES_MAXNDOTS) _resp->ndots = l; else _resp->ndots = RES_MAXNDOTS; #ifdef DEBUG if (_resp->options & RES_DEBUG) printf(";;\tndots=%u\n", _resp->ndots); #endif } } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) { #ifdef DEBUG if (!(_resp->options & RES_DEBUG)) { printf(";; res_setoptions(\"%s\", \"%s\")..\n", options, source); _resp->options |= RES_DEBUG; } printf(";;\tdebug\n"); #endif } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) { _resp->options |= RES_USE_INET6; } else if (!strncmp(cp, "insecure1", sizeof("insecure1") - 1)) { _resp->options |= RES_INSECURE1; } else if (!strncmp(cp, "insecure2", sizeof("insecure2") - 1)) { _resp->options |= RES_INSECURE2; } else if (!strncmp(cp, "edns0", sizeof("edns0") - 1)) { _resp->options |= RES_USE_EDNS0; } 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) /* XXX - should really use system's version of this */ { 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