/* $NetBSD: res_init.c,v 1.1.1.2 2012/09/09 16:08:09 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. */ #if defined(LIBC_SCCS) && !defined(lint) static const char sccsid[] = "@(#)res_init.c 8.1 (Berkeley) 6/7/93"; static const char rcsid[] = "Id: res_init.c,v 1.26 2008/12/11 09:59:00 marka Exp "; #endif /* LIBC_SCCS and not lint */ #include "port_before.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef HAVE_MD5 # include "../dst/md5.h" #else # ifdef SOLARIS2 # include # endif #endif #ifndef _MD5_H_ # define _MD5_H_ 1 /*%< make sure we do not include rsaref md5.h file */ #endif #include "port_after.h" /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */ #include #include "res_private.h" /*% Options. Should all be left alone. */ #define RESOLVSORT #define DEBUG #ifdef SOLARIS2 #include #endif static void res_setoptions __P((res_state, const char *, const 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. */ /*% * 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)); } /*% 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 */ int haveenv = 0; int havesearch = 0; #ifdef RESOLVSORT int nsort = 0; char *net; #endif int dots; union res_sockaddr_union u[2]; int maxns = MAXNS; RES_SET_H_ERRNO(statp, 0); if (statp->_u._ext.ext != NULL) res_ndestroy(statp); if (!preinit) { statp->retrans = RES_TIMEOUT; statp->retry = RES_DFLRETRY; statp->options = RES_DEFAULT; res_rndinit(statp); statp->id = res_nrandomid(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"); } else { /* * Historically res_init() rarely, if at all, failed. * Examples and applications exist which do not check * our return code. Furthermore several applications * simply call us to get the systems domainname. So * rather then immediately fail here we store the * failure, which is returned later, in h_errno. And * prevent the collection of 'nameserver' information * by setting maxns to 0. Thus applications that fail * to check our return code wont be able to make * queries anyhow. */ RES_SET_H_ERRNO(statp, NETDB_INTERNAL); maxns = 0; } #ifdef RESOLVSORT statp->nsort = 0; #endif res_setservers(statp, u, nserv); #ifdef SOLARIS2 /* * The old libresolv derived the defaultdomain from NIS/NIS+. * We want to keep this behaviour */ { char buf[sizeof(statp->defdname)], *cp; int ret; if ((ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf))) > 0 && (unsigned int)ret <= sizeof(buf)) { if (buf[0] == '+') buf[0] = '.'; cp = strchr(buf, '.'); cp = (cp == NULL) ? buf : (cp + 1); strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1); statp->defdname[sizeof(statp->defdname) - 1] = '\0'; } } #endif /* SOLARIS2 */ /* 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')) 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; } #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((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; } #endif if (MATCH(buf, "options")) { res_setoptions(statp, buf + sizeof("options") - 1, "conf"); continue; } } if (nserv > 0) statp->nscount = nserv; #ifdef RESOLVSORT statp->nsort = nsort; #endif (void) fclose(fp); } /* * 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"); statp->options |= RES_INIT; return (statp->res_h_errno); } 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 #ifdef SOLARIS2 } else if (!strncmp(cp, "retrans:", sizeof("retrans:") - 1)) { /* * For backward compatibility, 'retrans' is * supported as an alias for 'timeout', though * without an imposed maximum. */ statp->retrans = atoi(cp + sizeof("retrans:") - 1); } else if (!strncmp(cp, "retry:", sizeof("retry:") - 1)){ /* * For backward compatibility, 'retry' is * supported as an alias for 'attempts', though * without an imposed maximum. */ statp->retry = atoi(cp + sizeof("retry:") - 1); #endif /* SOLARIS2 */ } 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, 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, 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++; } } #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 void res_rndinit(res_state statp) { struct timeval now; u_int32_t u32; u_int16_t u16; gettimeofday(&now, NULL); u32 = now.tv_sec; memcpy(statp->_rnd, &u32, 4); u32 = now.tv_usec; memcpy(statp->_rnd + 4, &u32, 4); u32 += now.tv_sec; memcpy(statp->_rnd + 8, &u32, 4); u16 = getpid(); memcpy(statp->_rnd + 12, &u16, 2); } u_int res_nrandomid(res_state statp) { struct timeval now; u_int16_t u16; MD5_CTX ctx; gettimeofday(&now, NULL); u16 = (u_int16_t) (now.tv_sec ^ now.tv_usec); memcpy(statp->_rnd + 14, &u16, 2); #ifndef HAVE_MD5 MD5_Init(&ctx); MD5_Update(&ctx, statp->_rnd, 16); MD5_Final(statp->_rnd, &ctx); #else MD5Init(&ctx); MD5Update(&ctx, statp->_rnd, 16); MD5Final(statp->_rnd, &ctx); #endif memcpy(&u16, statp->_rnd + 14, 2); return ((u_int) u16); } /*% * 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); else statp->nsaddr_list[nserv].sin_family = 0; 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); } /*! \file */