gethostbydns.c revision 92889
121057Speter/* 221057Speter * ++Copyright++ 1985, 1988, 1993 321057Speter * - 43070Spst * Copyright (c) 1985, 1988, 1993 53070Spst * The Regents of the University of California. All rights reserved. 63070Spst * 73070Spst * Redistribution and use in source and binary forms, with or without 83070Spst * modification, are permitted provided that the following conditions 93070Spst * are met: 103070Spst * 1. Redistributions of source code must retain the above copyright 113070Spst * notice, this list of conditions and the following disclaimer. 123070Spst * 2. Redistributions in binary form must reproduce the above copyright 133070Spst * notice, this list of conditions and the following disclaimer in the 143070Spst * documentation and/or other materials provided with the distribution. 153070Spst * 3. All advertising materials mentioning features or use of this software 163070Spst * must display the following acknowledgement: 173070Spst * This product includes software developed by the University of 183070Spst * California, Berkeley and its contributors. 193070Spst * 4. Neither the name of the University nor the names of its contributors 203070Spst * may be used to endorse or promote products derived from this software 213070Spst * without specific prior written permission. 223070Spst * 233070Spst * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 243070Spst * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 253070Spst * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 263070Spst * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 273070Spst * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 283070Spst * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 293070Spst * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 303070Spst * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 313070Spst * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 323070Spst * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 333070Spst * SUCH DAMAGE. 343070Spst * - 353070Spst * Portions Copyright (c) 1993 by Digital Equipment Corporation. 368870Srgrimes * 373070Spst * Permission to use, copy, modify, and distribute this software for any 383070Spst * purpose with or without fee is hereby granted, provided that the above 393070Spst * copyright notice and this permission notice appear in all copies, and that 403070Spst * the name of Digital Equipment Corporation not be used in advertising or 413070Spst * publicity pertaining to distribution of the document or software without 423070Spst * specific, written prior permission. 438870Srgrimes * 443070Spst * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 453070Spst * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 463070Spst * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 473070Spst * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 483070Spst * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 493070Spst * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 503070Spst * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 513070Spst * SOFTWARE. 523070Spst * - 533070Spst * --Copyright-- 543070Spst */ 553070Spst 563070Spst#if defined(LIBC_SCCS) && !defined(lint) 573070Spststatic char sccsid[] = "@(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93"; 5835623Speterstatic char fromrcsid[] = "From: Id: gethnamaddr.c,v 8.23 1998/04/07 04:59:46 vixie Exp $"; 5950476Speterstatic char rcsid[] = "$FreeBSD: head/lib/libc/net/gethostbydns.c 92889 2002-03-21 18:49:23Z obrien $"; 603070Spst#endif /* LIBC_SCCS and not lint */ 613070Spst 6217903Speter#include <sys/types.h> 633070Spst#include <sys/param.h> 643070Spst#include <sys/socket.h> 653070Spst#include <netinet/in.h> 663070Spst#include <arpa/inet.h> 673070Spst#include <arpa/nameser.h> 6810133Speter 6910133Speter#include <stdio.h> 7011661Sphk#include <unistd.h> 7110133Speter#include <string.h> 723070Spst#include <netdb.h> 733070Spst#include <resolv.h> 743070Spst#include <ctype.h> 753070Spst#include <errno.h> 763070Spst#include <syslog.h> 7765532Snectar#include <stdarg.h> 7865532Snectar#include <nsswitch.h> 793070Spst 8010150Sbde#include "res_config.h" 813070Spst 8217903Speter#define SPRINTF(x) ((size_t)sprintf x) 8317903Speter 843070Spst#define MAXALIASES 35 853070Spst#define MAXADDRS 35 863070Spst 873070Spststatic const char AskedForGot[] = 8813408Speter "gethostby*.gethostanswer: asked for \"%s\", got \"%s\""; 893070Spst 903070Spststatic char *h_addr_ptrs[MAXADDRS + 1]; 913070Spst 923070Spststatic struct hostent host; 933070Spststatic char *host_aliases[MAXALIASES]; 943070Spststatic char hostbuf[8*1024]; 9517903Speterstatic u_char host_addr[16]; /* IPv4 or IPv6 */ 963070Spst 9713408Speter#ifdef RESOLVSORT 9813408Speterstatic void addrsort __P((char **, int)); 9913408Speter#endif 10013408Speter 10181975Skris#ifdef DEBUG 10281975Skrisstatic void dprintf(char *, int) __printflike(1, 0); 10381975Skris#endif 10481975Skris 1053070Spst#if PACKETSZ > 1024 1063070Spst#define MAXPACKET PACKETSZ 1073070Spst#else 1083070Spst#define MAXPACKET 1024 1093070Spst#endif 1103070Spst 1113070Spsttypedef union { 1123070Spst HEADER hdr; 1133070Spst u_char buf[MAXPACKET]; 1143070Spst} querybuf; 1153070Spst 1163070Spsttypedef union { 1173070Spst int32_t al; 1183070Spst char ac; 1193070Spst} align; 1203070Spst 1213070Spstextern int h_errno; 12219301Speterint _dns_ttl_; 1233070Spst 12410133Speter#ifdef DEBUG 12510133Speterstatic void 12610133Speterdprintf(msg, num) 12710133Speter char *msg; 12810133Speter int num; 12910133Speter{ 13010133Speter if (_res.options & RES_DEBUG) { 13110133Speter int save = errno; 13210133Speter 13310133Speter printf(msg, num); 13410133Speter errno = save; 13510133Speter } 13610133Speter} 13710133Speter#else 13810133Speter# define dprintf(msg, num) /*nada*/ 13910133Speter#endif 14010133Speter 14135623Speter#define BOUNDED_INCR(x) \ 14235623Speter do { \ 14335623Speter cp += x; \ 14435623Speter if (cp > eom) { \ 14535623Speter h_errno = NO_RECOVERY; \ 14635623Speter return (NULL); \ 14735623Speter } \ 14835623Speter } while (0) 14935623Speter 15035623Speter#define BOUNDS_CHECK(ptr, count) \ 15135623Speter do { \ 15235623Speter if ((ptr) + (count) > eom) { \ 15335623Speter h_errno = NO_RECOVERY; \ 15435623Speter return (NULL); \ 15535623Speter } \ 15635623Speter } while (0) 15735623Speter 1583070Spststatic struct hostent * 15917903Spetergethostanswer(answer, anslen, qname, qtype) 1603070Spst const querybuf *answer; 1613070Spst int anslen; 1623070Spst const char *qname; 16317903Speter int qtype; 1643070Spst{ 16592889Sobrien const HEADER *hp; 16692889Sobrien const u_char *cp; 16792889Sobrien int n; 16835623Speter const u_char *eom, *erdata; 1693070Spst char *bp, **ap, **hap; 1703070Spst int type, class, buflen, ancount, qdcount; 1713070Spst int haveanswer, had_error; 1723070Spst int toobig = 0; 17321057Speter char tbuf[MAXDNAME]; 17413408Speter const char *tname; 17517903Speter int (*name_ok) __P((const char *)); 1763070Spst 17713408Speter tname = qname; 1783070Spst host.h_name = NULL; 1793070Spst eom = answer->buf + anslen; 18017903Speter switch (qtype) { 18117903Speter case T_A: 18217903Speter case T_AAAA: 18317903Speter name_ok = res_hnok; 18417903Speter break; 18517903Speter case T_PTR: 18617903Speter name_ok = res_dnok; 18717903Speter break; 18817903Speter default: 18917903Speter h_errno = NO_RECOVERY; 19017903Speter return (NULL); /* XXX should be abort(); */ 19117903Speter } 1923070Spst /* 1933070Spst * find first satisfactory answer 1943070Spst */ 1953070Spst hp = &answer->hdr; 1963070Spst ancount = ntohs(hp->ancount); 1973070Spst qdcount = ntohs(hp->qdcount); 1983070Spst bp = hostbuf; 1993070Spst buflen = sizeof hostbuf; 20035623Speter cp = answer->buf; 20135623Speter BOUNDED_INCR(HFIXEDSZ); 2023070Spst if (qdcount != 1) { 2033070Spst h_errno = NO_RECOVERY; 2043070Spst return (NULL); 2053070Spst } 20617903Speter n = dn_expand(answer->buf, eom, cp, bp, buflen); 20717903Speter if ((n < 0) || !(*name_ok)(bp)) { 2083070Spst h_errno = NO_RECOVERY; 2093070Spst return (NULL); 2103070Spst } 21135623Speter BOUNDED_INCR(n + QFIXEDSZ); 21217903Speter if (qtype == T_A || qtype == T_AAAA) { 2133070Spst /* res_send() has already verified that the query name is the 2143070Spst * same as the one we sent; this just gets the expanded name 2153070Spst * (i.e., with the succeeding search-domain tacked on). 2163070Spst */ 2173070Spst n = strlen(bp) + 1; /* for the \0 */ 21826974Speter if (n >= MAXHOSTNAMELEN) { 21926974Speter h_errno = NO_RECOVERY; 22026974Speter return (NULL); 22126974Speter } 2223070Spst host.h_name = bp; 2233070Spst bp += n; 2243070Spst buflen -= n; 2253070Spst /* The qname can be abbreviated, but h_name is now absolute. */ 2263070Spst qname = host.h_name; 2273070Spst } 2283070Spst ap = host_aliases; 2293070Spst *ap = NULL; 2303070Spst host.h_aliases = host_aliases; 2313070Spst hap = h_addr_ptrs; 2323070Spst *hap = NULL; 2333070Spst host.h_addr_list = h_addr_ptrs; 2343070Spst haveanswer = 0; 2353070Spst had_error = 0; 23619301Speter _dns_ttl_ = -1; 2373070Spst while (ancount-- > 0 && cp < eom && !had_error) { 2383070Spst n = dn_expand(answer->buf, eom, cp, bp, buflen); 23917903Speter if ((n < 0) || !(*name_ok)(bp)) { 2403070Spst had_error++; 2413070Spst continue; 2423070Spst } 2433070Spst cp += n; /* name */ 24435623Speter BOUNDS_CHECK(cp, 3 * INT16SZ + INT32SZ); 2453070Spst type = _getshort(cp); 2463070Spst cp += INT16SZ; /* type */ 2473070Spst class = _getshort(cp); 24819301Speter cp += INT16SZ; /* class */ 24919301Speter if (qtype == T_A && type == T_A) 25019301Speter _dns_ttl_ = _getlong(cp); 25119301Speter cp += INT32SZ; /* TTL */ 2523070Spst n = _getshort(cp); 2533070Spst cp += INT16SZ; /* len */ 25435623Speter BOUNDS_CHECK(cp, n); 25535623Speter erdata = cp + n; 25617903Speter if (class != C_IN) { 2573070Spst /* XXX - debug? syslog? */ 2583070Spst cp += n; 2593070Spst continue; /* XXX - had_error++ ? */ 2603070Spst } 26117903Speter if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME) { 2623070Spst if (ap >= &host_aliases[MAXALIASES-1]) 2633070Spst continue; 2643070Spst n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 26517903Speter if ((n < 0) || !(*name_ok)(tbuf)) { 2663070Spst had_error++; 2673070Spst continue; 2683070Spst } 2693070Spst cp += n; 27035623Speter if (cp != erdata) { 27135623Speter h_errno = NO_RECOVERY; 27235623Speter return (NULL); 27335623Speter } 2743070Spst /* Store alias. */ 2753070Spst *ap++ = bp; 2763070Spst n = strlen(bp) + 1; /* for the \0 */ 27726974Speter if (n >= MAXHOSTNAMELEN) { 27826974Speter had_error++; 27926974Speter continue; 28026974Speter } 2813070Spst bp += n; 2823070Spst buflen -= n; 2833070Spst /* Get canonical name. */ 2843070Spst n = strlen(tbuf) + 1; /* for the \0 */ 28526974Speter if (n > buflen || n >= MAXHOSTNAMELEN) { 2863070Spst had_error++; 2873070Spst continue; 2883070Spst } 2893070Spst strcpy(bp, tbuf); 2903070Spst host.h_name = bp; 2913070Spst bp += n; 2923070Spst buflen -= n; 2933070Spst continue; 2943070Spst } 29513408Speter if (qtype == T_PTR && type == T_CNAME) { 29613408Speter n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); 29726974Speter if (n < 0 || !res_dnok(tbuf)) { 29813408Speter had_error++; 29913408Speter continue; 30013408Speter } 30113408Speter cp += n; 30235623Speter if (cp != erdata) { 30335623Speter h_errno = NO_RECOVERY; 30435623Speter return (NULL); 30535623Speter } 30613408Speter /* Get canonical name. */ 30713408Speter n = strlen(tbuf) + 1; /* for the \0 */ 30826974Speter if (n > buflen || n >= MAXHOSTNAMELEN) { 30913408Speter had_error++; 31013408Speter continue; 31113408Speter } 31213408Speter strcpy(bp, tbuf); 31313408Speter tname = bp; 31413408Speter bp += n; 31513408Speter buflen -= n; 31613408Speter continue; 31713408Speter } 3183070Spst if (type != qtype) { 31955174Srwatson if (type != T_SIG) 32055174Srwatson syslog(LOG_NOTICE|LOG_AUTH, 32121057Speter "gethostby*.gethostanswer: asked for \"%s %s %s\", got type \"%s\"", 32255174Srwatson qname, p_class(C_IN), p_type(qtype), 32355174Srwatson p_type(type)); 3243070Spst cp += n; 3253070Spst continue; /* XXX - had_error++ ? */ 3263070Spst } 3273070Spst switch (type) { 3283070Spst case T_PTR: 32913408Speter if (strcasecmp(tname, bp) != 0) { 3303070Spst syslog(LOG_NOTICE|LOG_AUTH, 3313070Spst AskedForGot, qname, bp); 3323070Spst cp += n; 3333070Spst continue; /* XXX - had_error++ ? */ 3343070Spst } 3353070Spst n = dn_expand(answer->buf, eom, cp, bp, buflen); 33617903Speter if ((n < 0) || !res_hnok(bp)) { 3373070Spst had_error++; 3383070Spst break; 3393070Spst } 34017903Speter#if MULTI_PTRS_ARE_ALIASES 3413070Spst cp += n; 34235623Speter if (cp != erdata) { 34335623Speter h_errno = NO_RECOVERY; 34435623Speter return (NULL); 34535623Speter } 3463070Spst if (!haveanswer) 3473070Spst host.h_name = bp; 3483070Spst else if (ap < &host_aliases[MAXALIASES-1]) 3493070Spst *ap++ = bp; 3503070Spst else 3513070Spst n = -1; 3523070Spst if (n != -1) { 3533070Spst n = strlen(bp) + 1; /* for the \0 */ 35426974Speter if (n >= MAXHOSTNAMELEN) { 35526974Speter had_error++; 35626974Speter break; 35726974Speter } 3583070Spst bp += n; 3593070Spst buflen -= n; 3603070Spst } 3613070Spst break; 3623070Spst#else 3633070Spst host.h_name = bp; 36417903Speter if (_res.options & RES_USE_INET6) { 36517903Speter n = strlen(bp) + 1; /* for the \0 */ 36626974Speter if (n >= MAXHOSTNAMELEN) { 36726974Speter had_error++; 36826974Speter break; 36926974Speter } 37017903Speter bp += n; 37117903Speter buflen -= n; 37217903Speter _map_v4v6_hostent(&host, &bp, &buflen); 37317903Speter } 37410133Speter h_errno = NETDB_SUCCESS; 3753070Spst return (&host); 3763070Spst#endif 3773070Spst case T_A: 37817903Speter case T_AAAA: 3793070Spst if (strcasecmp(host.h_name, bp) != 0) { 3803070Spst syslog(LOG_NOTICE|LOG_AUTH, 3813070Spst AskedForGot, host.h_name, bp); 3823070Spst cp += n; 3833070Spst continue; /* XXX - had_error++ ? */ 3843070Spst } 38518608Spst if (n != host.h_length) { 38618608Spst cp += n; 38718608Spst continue; 38818608Spst } 38918608Spst if (!haveanswer) { 39092889Sobrien int nn; 3913070Spst 3923070Spst host.h_name = bp; 3933070Spst nn = strlen(bp) + 1; /* for the \0 */ 3943070Spst bp += nn; 3953070Spst buflen -= nn; 3963070Spst } 3973070Spst 3983070Spst bp += sizeof(align) - ((u_long)bp % sizeof(align)); 3993070Spst 4003070Spst if (bp + n >= &hostbuf[sizeof hostbuf]) { 40110133Speter dprintf("size (%d) too big\n", n); 4023070Spst had_error++; 4033070Spst continue; 4043070Spst } 4053070Spst if (hap >= &h_addr_ptrs[MAXADDRS-1]) { 40610133Speter if (!toobig++) 40710133Speter dprintf("Too many addresses (%d)\n", 40813408Speter MAXADDRS); 4093070Spst cp += n; 4103070Spst continue; 4113070Spst } 4123070Spst bcopy(cp, *hap++ = bp, n); 4133070Spst bp += n; 41417903Speter buflen -= n; 4153070Spst cp += n; 41635623Speter if (cp != erdata) { 41735623Speter h_errno = NO_RECOVERY; 41835623Speter return (NULL); 41935623Speter } 4203070Spst break; 4213070Spst default: 42210133Speter dprintf("Impossible condition (type=%d)\n", type); 42310133Speter h_errno = NO_RECOVERY; 42410133Speter return (NULL); 42521057Speter /* BIND has abort() here, too risky on bad data */ 42621057Speter } 4273070Spst if (!had_error) 4283070Spst haveanswer++; 42921057Speter } 4303070Spst if (haveanswer) { 4313070Spst *ap = NULL; 4323070Spst *hap = NULL; 4333070Spst# if defined(RESOLVSORT) 4343070Spst /* 4353070Spst * Note: we sort even if host can take only one address 4363070Spst * in its return structures - should give it the "best" 4373070Spst * address in that case, not some random one 4383070Spst */ 43917903Speter if (_res.nsort && haveanswer > 1 && qtype == T_A) 4403070Spst addrsort(h_addr_ptrs, haveanswer); 4413070Spst# endif /*RESOLVSORT*/ 4423070Spst if (!host.h_name) { 4433070Spst n = strlen(qname) + 1; /* for the \0 */ 44426974Speter if (n > buflen || n >= MAXHOSTNAMELEN) 44526974Speter goto no_recovery; 4463070Spst strcpy(bp, qname); 4473070Spst host.h_name = bp; 44817903Speter bp += n; 44917903Speter buflen -= n; 4503070Spst } 45117903Speter if (_res.options & RES_USE_INET6) 45217903Speter _map_v4v6_hostent(&host, &bp, &buflen); 45310133Speter h_errno = NETDB_SUCCESS; 4543070Spst return (&host); 4553070Spst } 45626974Speter no_recovery: 45726974Speter h_errno = NO_RECOVERY; 45817903Speter return (NULL); 4593070Spst} 4603070Spst 4613070Spststruct hostent * 46220817Swpaul__dns_getanswer(answer, anslen, qname, qtype) 46320817Swpaul const char *answer; 46420817Swpaul int anslen; 46520817Swpaul const char *qname; 46620817Swpaul int qtype; 46720817Swpaul{ 46820892Swpaul switch(qtype) { 46920892Swpaul case T_AAAA: 47020892Swpaul host.h_addrtype = AF_INET6; 47120892Swpaul host.h_length = IN6ADDRSZ; 47220892Swpaul break; 47320892Swpaul case T_A: 47420892Swpaul default: 47520892Swpaul host.h_addrtype = AF_INET; 47620892Swpaul host.h_length = INADDRSZ; 47720892Swpaul break; 47820892Swpaul } 47920892Swpaul 48020817Swpaul return(gethostanswer((const querybuf *)answer, anslen, qname, qtype)); 48120817Swpaul} 48220817Swpaul 48365532Snectarint 48465532Snectar_dns_gethostbyname(void *rval, void *cb_data, va_list ap) 48565532Snectar{ 4863070Spst const char *name; 48717903Speter int af; 4883070Spst querybuf buf; 48992889Sobrien const char *cp; 49017903Speter char *bp; 49117903Speter int n, size, type, len; 4923070Spst 49365532Snectar name = va_arg(ap, const char *); 49465532Snectar af = va_arg(ap, int); 49565532Snectar *(struct hostent **)rval = NULL; 49665532Snectar 49710133Speter if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 49810133Speter h_errno = NETDB_INTERNAL; 49965532Snectar return NS_UNAVAIL; 50010133Speter } 50110133Speter 50217903Speter switch (af) { 50317903Speter case AF_INET: 50417903Speter size = INADDRSZ; 50517903Speter type = T_A; 50617903Speter break; 50717903Speter case AF_INET6: 50817903Speter size = IN6ADDRSZ; 50917903Speter type = T_AAAA; 51017903Speter break; 51117903Speter default: 51217903Speter h_errno = NETDB_INTERNAL; 51317903Speter errno = EAFNOSUPPORT; 51465532Snectar return NS_UNAVAIL; 51517903Speter } 51617903Speter 51717903Speter host.h_addrtype = af; 51817903Speter host.h_length = size; 51917903Speter 5203070Spst /* 52110133Speter * if there aren't any dots, it could be a user-level alias. 52210133Speter * this is also done in res_query() since we are not the only 52310133Speter * function that looks up host names. 52410133Speter */ 52510133Speter if (!strchr(name, '.') && (cp = __hostalias(name))) 52610133Speter name = cp; 52710133Speter 52810133Speter /* 5293070Spst * disallow names consisting only of digits/dots, unless 5303070Spst * they end in a dot. 5313070Spst */ 53252863Sache if (isdigit((unsigned char)name[0])) 5333070Spst for (cp = name;; ++cp) { 5343070Spst if (!*cp) { 5353070Spst if (*--cp == '.') 5363070Spst break; 5373070Spst /* 5383070Spst * All-numeric, no dot at the end. 5393070Spst * Fake up a hostent as if we'd actually 5403070Spst * done a lookup. 5413070Spst */ 54217903Speter if (inet_pton(af, name, host_addr) <= 0) { 5433070Spst h_errno = HOST_NOT_FOUND; 54465532Snectar return NS_NOTFOUND; 5453070Spst } 54610133Speter strncpy(hostbuf, name, MAXDNAME); 54710133Speter hostbuf[MAXDNAME] = '\0'; 54817903Speter bp = hostbuf + MAXDNAME; 54917903Speter len = sizeof hostbuf - MAXDNAME; 55010133Speter host.h_name = hostbuf; 5513070Spst host.h_aliases = host_aliases; 5523070Spst host_aliases[0] = NULL; 55317903Speter h_addr_ptrs[0] = (char *)host_addr; 5543070Spst h_addr_ptrs[1] = NULL; 5553070Spst host.h_addr_list = h_addr_ptrs; 55617903Speter if (_res.options & RES_USE_INET6) 55717903Speter _map_v4v6_hostent(&host, &bp, &len); 55813408Speter h_errno = NETDB_SUCCESS; 55965532Snectar *(struct hostent **)rval = &host; 56065532Snectar return NS_SUCCESS; 5613070Spst } 56252863Sache if (!isdigit((unsigned char)*cp) && *cp != '.') 5633070Spst break; 5643070Spst } 56552863Sache if ((isxdigit((unsigned char)name[0]) && strchr(name, ':') != NULL) || 56621433Sache name[0] == ':') 56721057Speter for (cp = name;; ++cp) { 56821057Speter if (!*cp) { 56921057Speter if (*--cp == '.') 57021057Speter break; 57121057Speter /* 57221057Speter * All-IPv6-legal, no dot at the end. 57321057Speter * Fake up a hostent as if we'd actually 57421057Speter * done a lookup. 57521057Speter */ 57621057Speter if (inet_pton(af, name, host_addr) <= 0) { 57721057Speter h_errno = HOST_NOT_FOUND; 57865532Snectar return NS_NOTFOUND; 57921057Speter } 58021057Speter strncpy(hostbuf, name, MAXDNAME); 58121057Speter hostbuf[MAXDNAME] = '\0'; 58221057Speter bp = hostbuf + MAXDNAME; 58321057Speter len = sizeof hostbuf - MAXDNAME; 58421057Speter host.h_name = hostbuf; 58521057Speter host.h_aliases = host_aliases; 58621057Speter host_aliases[0] = NULL; 58721057Speter h_addr_ptrs[0] = (char *)host_addr; 58821057Speter h_addr_ptrs[1] = NULL; 58921057Speter host.h_addr_list = h_addr_ptrs; 59021057Speter h_errno = NETDB_SUCCESS; 59165532Snectar *(struct hostent **)rval = &host; 59265532Snectar return NS_SUCCESS; 59321057Speter } 59452863Sache if (!isxdigit((unsigned char)*cp) && *cp != ':' && *cp != '.') 59521057Speter break; 59621057Speter } 59721433Sache 59817903Speter if ((n = res_search(name, C_IN, type, buf.buf, sizeof(buf))) < 0) { 59910133Speter dprintf("res_search failed (%d)\n", n); 60065532Snectar return NS_UNAVAIL; 6013070Spst } 60265532Snectar *(struct hostent **)rval = gethostanswer(&buf, n, name, type); 60365532Snectar return (*(struct hostent **)rval != NULL) ? NS_SUCCESS : NS_NOTFOUND; 6043070Spst} 6053070Spst 60665532Snectarint 60765532Snectar_dns_gethostbyaddr(void *rval, void *cb_data, va_list ap) 60865532Snectar{ 60917903Speter const char *addr; /* XXX should have been def'd as u_char! */ 61017903Speter int len, af; 61165532Snectar const u_char *uaddr; 61217903Speter static const u_char mapped[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff }; 61317903Speter static const u_char tunnelled[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 }; 61417903Speter int n, size; 6153070Spst querybuf buf; 61692889Sobrien struct hostent *hp; 61717903Speter char qbuf[MAXDNAME+1], *qp; 61810133Speter#ifdef SUNSECURITY 61992889Sobrien struct hostent *rhp; 62010133Speter char **haddr; 62110133Speter u_long old_options; 62210133Speter char hname2[MAXDNAME+1]; 62310133Speter#endif /*SUNSECURITY*/ 62465532Snectar 62565532Snectar addr = va_arg(ap, const char *); 62665532Snectar uaddr = (const u_char *)addr; 62765532Snectar len = va_arg(ap, int); 62865532Snectar af = va_arg(ap, int); 62913408Speter 63065532Snectar *(struct hostent **)rval = NULL; 63165532Snectar 63210133Speter if ((_res.options & RES_INIT) == 0 && res_init() == -1) { 63310133Speter h_errno = NETDB_INTERNAL; 63465532Snectar return NS_UNAVAIL; 63510133Speter } 63617903Speter if (af == AF_INET6 && len == IN6ADDRSZ && 63717903Speter (!bcmp(uaddr, mapped, sizeof mapped) || 63817903Speter !bcmp(uaddr, tunnelled, sizeof tunnelled))) { 63917903Speter /* Unmap. */ 64017903Speter addr += sizeof mapped; 64117903Speter uaddr += sizeof mapped; 64217903Speter af = AF_INET; 64317903Speter len = INADDRSZ; 64417903Speter } 64517903Speter switch (af) { 64617903Speter case AF_INET: 64717903Speter size = INADDRSZ; 64817903Speter break; 64917903Speter case AF_INET6: 65017903Speter size = IN6ADDRSZ; 65117903Speter break; 65217903Speter default: 65310133Speter errno = EAFNOSUPPORT; 65410133Speter h_errno = NETDB_INTERNAL; 65565532Snectar return NS_UNAVAIL; 65610133Speter } 65717903Speter if (size != len) { 65817903Speter errno = EINVAL; 65917903Speter h_errno = NETDB_INTERNAL; 66065532Snectar return NS_UNAVAIL; 66117903Speter } 66217903Speter switch (af) { 66317903Speter case AF_INET: 66417903Speter (void) sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa", 66517903Speter (uaddr[3] & 0xff), 66617903Speter (uaddr[2] & 0xff), 66717903Speter (uaddr[1] & 0xff), 66817903Speter (uaddr[0] & 0xff)); 66917903Speter break; 67017903Speter case AF_INET6: 67117903Speter qp = qbuf; 67217903Speter for (n = IN6ADDRSZ - 1; n >= 0; n--) { 67317903Speter qp += SPRINTF((qp, "%x.%x.", 67417903Speter uaddr[n] & 0xf, 67517903Speter (uaddr[n] >> 4) & 0xf)); 67617903Speter } 67717903Speter strcpy(qp, "ip6.int"); 67817903Speter break; 67917903Speter default: 68017903Speter abort(); 68117903Speter } 6823070Spst n = res_query(qbuf, C_IN, T_PTR, (u_char *)buf.buf, sizeof buf.buf); 6833070Spst if (n < 0) { 68410133Speter dprintf("res_query failed (%d)\n", n); 68565532Snectar return NS_UNAVAIL; 6863070Spst } 68757252Sfenner if (n > sizeof buf.buf) { 68857252Sfenner dprintf("static buffer is too small (%d)\n", n); 68965532Snectar return NS_UNAVAIL; 69057252Sfenner } 69117903Speter if (!(hp = gethostanswer(&buf, n, qbuf, T_PTR))) 69265532Snectar return NS_NOTFOUND; /* h_errno was set by gethostanswer() */ 69310133Speter#ifdef SUNSECURITY 69417903Speter if (af == AF_INET) { 69517903Speter /* 69617903Speter * turn off search as the name should be absolute, 69717903Speter * 'localhost' should be matched by defnames 69817903Speter */ 69917903Speter strncpy(hname2, hp->h_name, MAXDNAME); 70017903Speter hname2[MAXDNAME] = '\0'; 70117903Speter old_options = _res.options; 70217903Speter _res.options &= ~RES_DNSRCH; 70317903Speter _res.options |= RES_DEFNAMES; 70417903Speter if (!(rhp = gethostbyname(hname2))) { 70510133Speter syslog(LOG_NOTICE|LOG_AUTH, 70610133Speter "gethostbyaddr: No A record for %s (verifying [%s])", 70710133Speter hname2, inet_ntoa(*((struct in_addr *)addr))); 70810133Speter _res.options = old_options; 70910133Speter h_errno = HOST_NOT_FOUND; 71065532Snectar return NS_NOTFOUND; 71117903Speter } 71217903Speter _res.options = old_options; 71317903Speter for (haddr = rhp->h_addr_list; *haddr; haddr++) 71410133Speter if (!memcmp(*haddr, addr, INADDRSZ)) 71510133Speter break; 71617903Speter if (!*haddr) { 71710133Speter syslog(LOG_NOTICE|LOG_AUTH, 71810133Speter "gethostbyaddr: A record of %s != PTR record [%s]", 71910133Speter hname2, inet_ntoa(*((struct in_addr *)addr))); 72010133Speter h_errno = HOST_NOT_FOUND; 72165532Snectar return NS_NOTFOUND; 72217903Speter } 72310133Speter } 72410133Speter#endif /*SUNSECURITY*/ 72517903Speter hp->h_addrtype = af; 7263070Spst hp->h_length = len; 72717903Speter bcopy(addr, host_addr, len); 72817903Speter h_addr_ptrs[0] = (char *)host_addr; 7293070Spst h_addr_ptrs[1] = NULL; 73017903Speter if (af == AF_INET && (_res.options & RES_USE_INET6)) { 73117903Speter _map_v4v6_address((char*)host_addr, (char*)host_addr); 73217903Speter hp->h_addrtype = AF_INET6; 73317903Speter hp->h_length = IN6ADDRSZ; 73417903Speter } 73510133Speter h_errno = NETDB_SUCCESS; 73665532Snectar *(struct hostent **)rval = hp; 73765532Snectar return (hp != NULL) ? NS_SUCCESS : NS_NOTFOUND; 7383070Spst} 7393070Spst 74013408Speter#ifdef RESOLVSORT 74113408Speterstatic void 74213408Speteraddrsort(ap, num) 74313408Speter char **ap; 74413408Speter int num; 74513408Speter{ 74613408Speter int i, j; 74713408Speter char **p; 74813408Speter short aval[MAXADDRS]; 74913408Speter int needsort = 0; 75013408Speter 75113408Speter p = ap; 75213408Speter for (i = 0; i < num; i++, p++) { 75313408Speter for (j = 0 ; (unsigned)j < _res.nsort; j++) 75413408Speter if (_res.sort_list[j].addr.s_addr == 75513408Speter (((struct in_addr *)(*p))->s_addr & _res.sort_list[j].mask)) 75613408Speter break; 75713408Speter aval[i] = j; 75813408Speter if (needsort == 0 && i > 0 && j < aval[i-1]) 75913408Speter needsort = i; 76013408Speter } 76113408Speter if (!needsort) 76213408Speter return; 76313408Speter 76413408Speter while (needsort < num) { 76513408Speter for (j = needsort - 1; j >= 0; j--) { 76613408Speter if (aval[j] > aval[j+1]) { 76713408Speter char *hp; 76813408Speter 76913408Speter i = aval[j]; 77013408Speter aval[j] = aval[j+1]; 77113408Speter aval[j+1] = i; 77213408Speter 77313408Speter hp = ap[j]; 77413408Speter ap[j] = ap[j+1]; 77513408Speter ap[j+1] = hp; 77613408Speter 77713408Speter } else 77813408Speter break; 77913408Speter } 78013408Speter needsort++; 78113408Speter } 78213408Speter} 78313408Speter#endif 7843070Spstvoid 7853070Spst_sethostdnsent(stayopen) 7863070Spst int stayopen; 7873070Spst{ 78813408Speter if ((_res.options & RES_INIT) == 0 && res_init() == -1) 78913408Speter return; 7903070Spst if (stayopen) 7913070Spst _res.options |= RES_STAYOPEN | RES_USEVC; 7923070Spst} 7933070Spst 7943070Spstvoid 7953070Spst_endhostdnsent() 7963070Spst{ 7973070Spst _res.options &= ~(RES_STAYOPEN | RES_USEVC); 79823766Speter res_close(); 7993070Spst} 800