/* $NetBSD: gethnamaddr.c,v 1.73 2007/01/27 22:27:35 christos Exp $ */ /* * ++Copyright++ 1985, 1988, 1993 * - * Copyright (c) 1985, 1988, 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. * - * --Copyright-- */ #include #if defined(LIBC_SCCS) && !defined(lint) #if 0 static char sccsid[] = "@(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93"; static char rcsid[] = "Id: gethnamaddr.c,v 8.21 1997/06/01 20:34:37 vixie Exp "; #else __RCSID("$NetBSD: gethnamaddr.c,v 1.73 2007/01/27 22:27:35 christos Exp $"); #endif #endif /* LIBC_SCCS and not lint */ #if defined(_LIBC) #include "namespace.h" #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef LOG_AUTH # define LOG_AUTH 0 #endif #define MULTI_PTRS_ARE_ALIASES 1 /* XXX - experimental */ #include #include #include #ifdef YP #include #include #include #endif #if defined(_LIBC) && defined(__weak_alias) __weak_alias(gethostbyaddr,_gethostbyaddr) __weak_alias(gethostbyname,_gethostbyname) __weak_alias(gethostent,_gethostent) #endif #define MAXALIASES 35 #define MAXADDRS 35 static const char AskedForGot[] = "gethostby*.getanswer: asked for \"%s\", got \"%s\""; static char *h_addr_ptrs[MAXADDRS + 1]; #ifdef YP static char *__ypdomain; #endif static struct hostent host; static char *host_aliases[MAXALIASES]; static char hostbuf[8*1024]; static u_int32_t host_addr[16 / sizeof(u_int32_t)]; /* IPv4 or IPv6 */ static FILE *hostf = NULL; static int stayopen = 0; #define MAXPACKET (64*1024) typedef union { HEADER hdr; u_char buf[MAXPACKET]; } querybuf; typedef union { int32_t al; char ac; } align; #ifdef DEBUG static void dprintf(const char *, res_state, ...) __attribute__((__format__(__printf__, 1, 3))); #endif static struct hostent *getanswer(const querybuf *, int, const char *, int, res_state); static void map_v4v6_address(const char *, char *); static void map_v4v6_hostent(struct hostent *, char **, char *); static void addrsort(char **, int, res_state); void _sethtent(int); void _endhtent(void); struct hostent *_gethtent(void); void ht_sethostent(int); void ht_endhostent(void); struct hostent *ht_gethostbyname(char *); struct hostent *ht_gethostbyaddr(const char *, int, int); void dns_service(void); #undef dn_skipname int dn_skipname(const u_char *, const u_char *); int _gethtbyaddr(void *, void *, va_list); int _gethtbyname(void *, void *, va_list); struct hostent *_gethtbyname2(const char *, int); int _dns_gethtbyaddr(void *, void *, va_list); int _dns_gethtbyname(void *, void *, va_list); #ifdef YP struct hostent *_yphostent(char *, int); int _yp_gethtbyaddr(void *, void *, va_list); int _yp_gethtbyname(void *, void *, va_list); #endif static struct hostent *gethostbyname_internal(const char *, int, res_state); static const ns_src default_dns_files[] = { { NSSRC_FILES, NS_SUCCESS }, { NSSRC_DNS, NS_SUCCESS }, { 0, 0 } }; #ifdef DEBUG static void dprintf(const char *msg, res_state res, ...) { _DIAGASSERT(msg != NULL); if (res->options & RES_DEBUG) { int save = errno; va_list ap; va_start (ap, res); vprintf(msg, ap); va_end (ap); errno = save; } } #else # define dprintf(msg, res, num) /*nada*/ #endif #define BOUNDED_INCR(x) \ do { \ cp += (x); \ if (cp > eom) { \ h_errno = NO_RECOVERY; \ return NULL; \ } \ } while (/*CONSTCOND*/0) #define BOUNDS_CHECK(ptr, count) \ do { \ if ((ptr) + (count) > eom) { \ h_errno = NO_RECOVERY; \ return NULL; \ } \ } while (/*CONSTCOND*/0) static struct hostent * getanswer(const querybuf *answer, int anslen, const char *qname, int qtype, res_state res) { const HEADER *hp; const u_char *cp; int n; const u_char *eom, *erdata; char *bp, **ap, **hap, *ep; int type, class, ancount, qdcount; int haveanswer, had_error; int toobig = 0; char tbuf[MAXDNAME]; const char *tname; int (*name_ok)(const char *); _DIAGASSERT(answer != NULL); _DIAGASSERT(qname != NULL); tname = qname; host.h_name = NULL; eom = answer->buf + anslen; switch (qtype) { case T_A: case T_AAAA: name_ok = res_hnok; break; case T_PTR: name_ok = res_dnok; break; default: return NULL; /* XXX should be abort(); */ } /* * find first satisfactory answer */ hp = &answer->hdr; ancount = ntohs(hp->ancount); qdcount = ntohs(hp->qdcount); bp = hostbuf; ep = hostbuf + sizeof hostbuf; cp = answer->buf; BOUNDED_INCR(HFIXEDSZ); if (qdcount != 1) { h_errno = NO_RECOVERY; return NULL; } n = dn_expand(answer->buf, eom, cp, bp, ep - bp); if ((n < 0) || !(*name_ok)(bp)) { h_errno = NO_RECOVERY; return NULL; } BOUNDED_INCR(n + QFIXEDSZ); if (qtype == T_A || qtype == T_AAAA) { /* res_send() has already verified that the query name is the * same as the one we sent; this just gets the expanded name * (i.e., with the succeeding search-domain tacked on). */ n = strlen(bp) + 1; /* for the \0 */ if (n >= MAXHOSTNAMELEN) { h_errno = NO_RECOVERY; return NULL; } host.h_name = bp; bp += n; /* The qname can be abbreviated, but h_name is now absolute. */ qname = host.h_name; } ap = host_aliases; *ap = NULL; host.h_aliases = host_aliases; hap = h_addr_ptrs; *hap = NULL; host.h_addr_list = h_addr_ptrs; haveanswer = 0; had_error = 0; while (ancount-- > 0 && cp < eom && !had_error) { n = dn_expand(answer->buf, eom, cp, bp, ep - bp); if ((n < 0) || !(*name_ok)(bp)) { had_error++; continue; } cp += n; /* name */ BOUNDS_CHECK(cp, 3 * INT16SZ + INT32SZ); type = _getshort(cp); cp += INT16SZ; /* type */ class = _getshort(cp); cp += INT16SZ + INT32SZ; /* class, TTL */ n = _getshort(cp); cp += INT16SZ; /* len */ BOUNDS_CHECK(cp, n); erdata = cp + n; if (class != C_IN) { /* XXX - debug? syslog? */ cp += n; continue; /* XXX - had_error++ ? */ } if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME) { if (ap >= &host_aliases[MAXALIASES-1]) continue; n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); if ((n < 0) || !(*name_ok)(tbuf)) { had_error++; continue; } cp += n; if (cp != erdata) { h_errno = NO_RECOVERY; return NULL; } /* Store alias. */ *ap++ = bp; n = strlen(bp) + 1; /* for the \0 */ if (n >= MAXHOSTNAMELEN) { had_error++; continue; } bp += n; /* Get canonical name. */ n = strlen(tbuf) + 1; /* for the \0 */ if (n > ep - bp || n >= MAXHOSTNAMELEN) { had_error++; continue; } strlcpy(bp, tbuf, (size_t)(ep - bp)); host.h_name = bp; bp += n; continue; } if (qtype == T_PTR && type == T_CNAME) { n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); if (n < 0 || !res_dnok(tbuf)) { had_error++; continue; } cp += n; if (cp != erdata) { h_errno = NO_RECOVERY; return NULL; } /* Get canonical name. */ n = strlen(tbuf) + 1; /* for the \0 */ if (n > ep - bp || n >= MAXHOSTNAMELEN) { had_error++; continue; } strlcpy(bp, tbuf, (size_t)(ep - bp)); tname = bp; bp += n; continue; } if (type != qtype) { if (type != T_KEY && type != T_SIG) syslog(LOG_NOTICE|LOG_AUTH, "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", qname, p_class(C_IN), p_type(qtype), p_type(type)); cp += n; continue; /* XXX - had_error++ ? */ } switch (type) { case T_PTR: if (strcasecmp(tname, bp) != 0) { syslog(LOG_NOTICE|LOG_AUTH, AskedForGot, qname, bp); cp += n; continue; /* XXX - had_error++ ? */ } n = dn_expand(answer->buf, eom, cp, bp, ep - bp); if ((n < 0) || !res_hnok(bp)) { had_error++; break; } #if MULTI_PTRS_ARE_ALIASES cp += n; if (cp != erdata) { h_errno = NO_RECOVERY; return NULL; } if (!haveanswer) host.h_name = bp; else if (ap < &host_aliases[MAXALIASES-1]) *ap++ = bp; else n = -1; if (n != -1) { n = strlen(bp) + 1; /* for the \0 */ if (n >= MAXHOSTNAMELEN) { had_error++; break; } bp += n; } break; #else host.h_name = bp; if (res->options & RES_USE_INET6) { n = strlen(bp) + 1; /* for the \0 */ if (n >= MAXHOSTNAMELEN) { had_error++; break; } bp += n; map_v4v6_hostent(&host, &bp, ep); } h_errno = NETDB_SUCCESS; return &host; #endif case T_A: case T_AAAA: if (strcasecmp(host.h_name, bp) != 0) { syslog(LOG_NOTICE|LOG_AUTH, AskedForGot, host.h_name, bp); cp += n; continue; /* XXX - had_error++ ? */ } if (n != host.h_length) { cp += n; continue; } if (type == T_AAAA) { struct in6_addr in6; memcpy(&in6, cp, IN6ADDRSZ); if (IN6_IS_ADDR_V4MAPPED(&in6)) { cp += n; continue; } } if (!haveanswer) { int nn; host.h_name = bp; nn = strlen(bp) + 1; /* for the \0 */ bp += nn; } bp += sizeof(align) - (size_t)((u_long)bp % sizeof(align)); if (bp + n >= &hostbuf[sizeof hostbuf]) { dprintf("size (%d) too big\n", res, n); had_error++; continue; } if (hap >= &h_addr_ptrs[MAXADDRS-1]) { if (!toobig++) { dprintf("Too many addresses (%d)\n", res, MAXADDRS); } cp += n; continue; } (void)memcpy(*hap++ = bp, cp, (size_t)n); bp += n; cp += n; if (cp != erdata) { h_errno = NO_RECOVERY; return NULL; } break; default: abort(); } if (!had_error) haveanswer++; } if (haveanswer) { *ap = NULL; *hap = NULL; /* * Note: we sort even if host can take only one address * in its return structures - should give it the "best" * address in that case, not some random one */ if (res->nsort && haveanswer > 1 && qtype == T_A) addrsort(h_addr_ptrs, haveanswer, res); if (!host.h_name) { n = strlen(qname) + 1; /* for the \0 */ if (n > ep - bp || n >= MAXHOSTNAMELEN) goto no_recovery; strlcpy(bp, qname, (size_t)(ep - bp)); host.h_name = bp; bp += n; } if (res->options & RES_USE_INET6) map_v4v6_hostent(&host, &bp, ep); h_errno = NETDB_SUCCESS; return &host; } no_recovery: h_errno = NO_RECOVERY; return NULL; } struct hostent * gethostbyname(const char *name) { struct hostent *hp; res_state res = __res_get_state(); if (res == NULL) return NULL; _DIAGASSERT(name != NULL); if (res->options & RES_USE_INET6) { hp = gethostbyname_internal(name, AF_INET6, res); if (hp) { __res_put_state(res); return hp; } } hp = gethostbyname_internal(name, AF_INET, res); __res_put_state(res); return hp; } struct hostent * gethostbyname2(const char *name, int af) { struct hostent *hp; res_state res = __res_get_state(); if (res == NULL) return NULL; hp = gethostbyname_internal(name, af, res); __res_put_state(res); return hp; } static struct hostent * gethostbyname_internal(const char *name, int af, res_state res) { const char *cp; char *bp, *ep; int size; struct hostent *hp; static const ns_dtab dtab[] = { NS_FILES_CB(_gethtbyname, NULL) { NSSRC_DNS, _dns_gethtbyname, NULL }, /* force -DHESIOD */ NS_NIS_CB(_yp_gethtbyname, NULL) NS_NULL_CB }; _DIAGASSERT(name != NULL); switch (af) { case AF_INET: size = INADDRSZ; break; case AF_INET6: size = IN6ADDRSZ; break; default: h_errno = NETDB_INTERNAL; errno = EAFNOSUPPORT; return NULL; } host.h_addrtype = af; host.h_length = size; /* * if there aren't any dots, it could be a user-level alias. * this is also done in res_nquery() since we are not the only * function that looks up host names. */ if (!strchr(name, '.') && (cp = __hostalias(name))) name = cp; /* * disallow names consisting only of digits/dots, unless * they end in a dot. */ if (isdigit((u_char) name[0])) for (cp = name;; ++cp) { if (!*cp) { if (*--cp == '.') break; /* * All-numeric, no dot at the end. * Fake up a hostent as if we'd actually * done a lookup. */ if (inet_pton(af, name, (char *)(void *)host_addr) <= 0) { h_errno = HOST_NOT_FOUND; return NULL; } strncpy(hostbuf, name, MAXDNAME); hostbuf[MAXDNAME] = '\0'; bp = hostbuf + MAXDNAME; ep = hostbuf + sizeof hostbuf; host.h_name = hostbuf; host.h_aliases = host_aliases; host_aliases[0] = NULL; h_addr_ptrs[0] = (char *)(void *)host_addr; h_addr_ptrs[1] = NULL; host.h_addr_list = h_addr_ptrs; if (res->options & RES_USE_INET6) map_v4v6_hostent(&host, &bp, ep); h_errno = NETDB_SUCCESS; return &host; } if (!isdigit((u_char) *cp) && *cp != '.') break; } if ((isxdigit((u_char) name[0]) && strchr(name, ':') != NULL) || name[0] == ':') for (cp = name;; ++cp) { if (!*cp) { if (*--cp == '.') break; /* * All-IPv6-legal, no dot at the end. * Fake up a hostent as if we'd actually * done a lookup. */ if (inet_pton(af, name, (char *)(void *)host_addr) <= 0) { h_errno = HOST_NOT_FOUND; return NULL; } strncpy(hostbuf, name, MAXDNAME); hostbuf[MAXDNAME] = '\0'; bp = hostbuf + MAXDNAME; ep = hostbuf + sizeof hostbuf; host.h_name = hostbuf; host.h_aliases = host_aliases; host_aliases[0] = NULL; h_addr_ptrs[0] = (char *)(void *)host_addr; h_addr_ptrs[1] = NULL; host.h_addr_list = h_addr_ptrs; h_errno = NETDB_SUCCESS; return &host; } if (!isxdigit((u_char) *cp) && *cp != ':' && *cp != '.') break; } hp = NULL; h_errno = NETDB_INTERNAL; if (nsdispatch(&hp, dtab, NSDB_HOSTS, "gethostbyname", default_dns_files, name, strlen(name), af) != NS_SUCCESS) return NULL; h_errno = NETDB_SUCCESS; return hp; } struct hostent * gethostbyaddr(const char *addr, /* XXX should have been def'd as u_char! */ socklen_t len, int af) { const u_char *uaddr = (const u_char *)addr; socklen_t size; struct hostent *hp; static const ns_dtab dtab[] = { NS_FILES_CB(_gethtbyaddr, NULL) { NSSRC_DNS, _dns_gethtbyaddr, NULL }, /* force -DHESIOD */ NS_NIS_CB(_yp_gethtbyaddr, NULL) NS_NULL_CB }; _DIAGASSERT(addr != NULL); if (af == AF_INET6 && len == IN6ADDRSZ && (IN6_IS_ADDR_LINKLOCAL((const struct in6_addr *)(const void *)uaddr) || IN6_IS_ADDR_SITELOCAL((const struct in6_addr *)(const void *)uaddr))) { h_errno = HOST_NOT_FOUND; return NULL; } if (af == AF_INET6 && len == IN6ADDRSZ && (IN6_IS_ADDR_V4MAPPED((const struct in6_addr *)(const void *)uaddr) || IN6_IS_ADDR_V4COMPAT((const struct in6_addr *)(const void *)uaddr))) { /* Unmap. */ addr += IN6ADDRSZ - INADDRSZ; uaddr += IN6ADDRSZ - INADDRSZ; af = AF_INET; len = INADDRSZ; } switch (af) { case AF_INET: size = INADDRSZ; break; case AF_INET6: size = IN6ADDRSZ; break; default: errno = EAFNOSUPPORT; h_errno = NETDB_INTERNAL; return NULL; } if (size != len) { errno = EINVAL; h_errno = NETDB_INTERNAL; return NULL; } hp = NULL; h_errno = NETDB_INTERNAL; if (nsdispatch(&hp, dtab, NSDB_HOSTS, "gethostbyaddr", default_dns_files, uaddr, len, af) != NS_SUCCESS) return NULL; h_errno = NETDB_SUCCESS; return hp; } void _sethtent(int f) { if (!hostf) hostf = fopen(_PATH_HOSTS, "r" ); else rewind(hostf); stayopen = f; } void _endhtent(void) { if (hostf && !stayopen) { (void) fclose(hostf); hostf = NULL; } } struct hostent * _gethtent(void) { char *p; char *cp, **q; int af, len; if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) { h_errno = NETDB_INTERNAL; return NULL; } again: if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) { h_errno = HOST_NOT_FOUND; return NULL; } if (*p == '#') goto again; if (!(cp = strpbrk(p, "#\n"))) goto again; *cp = '\0'; if (!(cp = strpbrk(p, " \t"))) goto again; *cp++ = '\0'; if (inet_pton(AF_INET6, p, (char *)(void *)host_addr) > 0) { af = AF_INET6; len = IN6ADDRSZ; } else if (inet_pton(AF_INET, p, (char *)(void *)host_addr) > 0) { res_state res = __res_get_state(); if (res == NULL) return NULL; if (res->options & RES_USE_INET6) { map_v4v6_address((char *)(void *)host_addr, (char *)(void *)host_addr); af = AF_INET6; len = IN6ADDRSZ; } else { af = AF_INET; len = INADDRSZ; } __res_put_state(res); } else { goto again; } /* if this is not something we're looking for, skip it. */ if (host.h_addrtype != 0 && host.h_addrtype != af) goto again; if (host.h_length != 0 && host.h_length != len) goto again; h_addr_ptrs[0] = (char *)(void *)host_addr; h_addr_ptrs[1] = NULL; host.h_addr_list = h_addr_ptrs; host.h_length = len; host.h_addrtype = af; while (*cp == ' ' || *cp == '\t') cp++; host.h_name = cp; q = host.h_aliases = host_aliases; if ((cp = strpbrk(cp, " \t")) != NULL) *cp++ = '\0'; while (cp && *cp) { if (*cp == ' ' || *cp == '\t') { cp++; continue; } if (q < &host_aliases[MAXALIASES - 1]) *q++ = cp; if ((cp = strpbrk(cp, " \t")) != NULL) *cp++ = '\0'; } *q = NULL; h_errno = NETDB_SUCCESS; return &host; } /*ARGSUSED*/ int _gethtbyname(void *rv, void *cb_data, va_list ap) { struct hostent *hp; const char *name; int af; _DIAGASSERT(rv != NULL); name = va_arg(ap, char *); /* NOSTRICT skip len */(void)va_arg(ap, int); af = va_arg(ap, int); hp = NULL; #if 0 { res_state res = __res_get_state(); if (res == NULL) return NS_NOTFOUND; if (res->options & RES_USE_INET6) hp = _gethtbyname2(name, AF_INET6); if (hp==NULL) hp = _gethtbyname2(name, AF_INET); __res_put_state(res); } #else hp = _gethtbyname2(name, af); #endif *((struct hostent **)rv) = hp; if (hp == NULL) { h_errno = HOST_NOT_FOUND; return NS_NOTFOUND; } return NS_SUCCESS; } struct hostent * _gethtbyname2(const char *name, int af) { struct hostent *p; char *tmpbuf, *ptr, **cp; int num; size_t len; _DIAGASSERT(name != NULL); _sethtent(stayopen); ptr = tmpbuf = NULL; num = 0; while ((p = _gethtent()) != NULL && num < MAXADDRS) { if (p->h_addrtype != af) continue; if (strcasecmp(p->h_name, name) != 0) { for (cp = p->h_aliases; *cp != NULL; cp++) if (strcasecmp(*cp, name) == 0) break; if (*cp == NULL) continue; } if (num == 0) { size_t bufsize; char *src; bufsize = strlen(p->h_name) + 2 + MAXADDRS * p->h_length + ALIGNBYTES; for (cp = p->h_aliases; *cp != NULL; cp++) bufsize += strlen(*cp) + 1; if ((tmpbuf = malloc(bufsize)) == NULL) { h_errno = NETDB_INTERNAL; return NULL; } ptr = tmpbuf; src = p->h_name; while ((*ptr++ = *src++) != '\0'); for (cp = p->h_aliases; *cp != NULL; cp++) { src = *cp; while ((*ptr++ = *src++) != '\0'); } *ptr++ = '\0'; ptr = (char *)(void *)ALIGN(ptr); } (void)memcpy(ptr, p->h_addr_list[0], (size_t)p->h_length); ptr += p->h_length; num++; } _endhtent(); if (num == 0) return NULL; len = ptr - tmpbuf; if (len > (sizeof(hostbuf) - ALIGNBYTES)) { free(tmpbuf); errno = ENOSPC; h_errno = NETDB_INTERNAL; return NULL; } ptr = memcpy((void *)ALIGN(hostbuf), tmpbuf, len); free(tmpbuf); host.h_name = ptr; while (*ptr++); cp = host_aliases; while (*ptr) { *cp++ = ptr; while (*ptr++); } ptr++; *cp = NULL; ptr = (char *)(void *)ALIGN(ptr); cp = h_addr_ptrs; while (num--) { *cp++ = ptr; ptr += host.h_length; } *cp = NULL; return &host; } /*ARGSUSED*/ int _gethtbyaddr(void *rv, void *cb_data, va_list ap) { struct hostent *p; const unsigned char *addr; int len, af; _DIAGASSERT(rv != NULL); addr = va_arg(ap, unsigned char *); len = va_arg(ap, int); af = va_arg(ap, int); host.h_length = len; host.h_addrtype = af; _sethtent(stayopen); while ((p = _gethtent()) != NULL) if (p->h_addrtype == af && !memcmp(p->h_addr, addr, (size_t)len)) break; _endhtent(); *((struct hostent **)rv) = p; if (p==NULL) { h_errno = HOST_NOT_FOUND; return NS_NOTFOUND; } return NS_SUCCESS; } static void map_v4v6_address(const char *src, char *dst) { u_char *p = (u_char *)dst; char tmp[INADDRSZ]; int i; _DIAGASSERT(src != NULL); _DIAGASSERT(dst != NULL); /* Stash a temporary copy so our caller can update in place. */ (void)memcpy(tmp, src, INADDRSZ); /* Mark this ipv6 addr as a mapped ipv4. */ for (i = 0; i < 10; i++) *p++ = 0x00; *p++ = 0xff; *p++ = 0xff; /* Retrieve the saved copy and we're done. */ (void)memcpy((void *)p, tmp, INADDRSZ); } static void map_v4v6_hostent(struct hostent *hp, char **bpp, char *ep) { char **ap; _DIAGASSERT(hp != NULL); _DIAGASSERT(bpp != NULL); _DIAGASSERT(ep != NULL); if (hp->h_addrtype != AF_INET || hp->h_length != INADDRSZ) return; hp->h_addrtype = AF_INET6; hp->h_length = IN6ADDRSZ; for (ap = hp->h_addr_list; *ap; ap++) { int i = sizeof(align) - (size_t)((u_long)*bpp % sizeof(align)); if (ep - *bpp < (i + IN6ADDRSZ)) { /* Out of memory. Truncate address list here. XXX */ *ap = NULL; return; } *bpp += i; map_v4v6_address(*ap, *bpp); *ap = *bpp; *bpp += IN6ADDRSZ; } } static void addrsort(char **ap, int num, res_state res) { int i, j; char **p; short aval[MAXADDRS]; int needsort = 0; _DIAGASSERT(ap != NULL); p = ap; for (i = 0; i < num; i++, p++) { for (j = 0 ; (unsigned)j < res->nsort; j++) if (res->sort_list[j].addr.s_addr == (((struct in_addr *)(void *)(*p))->s_addr & res->sort_list[j].mask)) break; aval[i] = j; if (needsort == 0 && i > 0 && j < aval[i-1]) needsort = i; } if (!needsort) return; while (needsort < num) { for (j = needsort - 1; j >= 0; j--) { if (aval[j] > aval[j+1]) { char *hp; i = aval[j]; aval[j] = aval[j+1]; aval[j+1] = i; hp = ap[j]; ap[j] = ap[j+1]; ap[j+1] = hp; } else break; } needsort++; } } struct hostent * gethostent(void) { host.h_addrtype = 0; host.h_length = 0; return _gethtent(); } /*ARGSUSED*/ int _dns_gethtbyname(void *rv, void *cb_data, va_list ap) { querybuf *buf; int n, type; struct hostent *hp; const char *name; int af; res_state res; _DIAGASSERT(rv != NULL); name = va_arg(ap, char *); /* NOSTRICT skip len */(void)va_arg(ap, int); af = va_arg(ap, int); switch (af) { case AF_INET: type = T_A; break; case AF_INET6: type = T_AAAA; break; default: return NS_UNAVAIL; } buf = malloc(sizeof(*buf)); if (buf == NULL) { h_errno = NETDB_INTERNAL; return NS_NOTFOUND; } res = __res_get_state(); if (res == NULL) { free(buf); return NS_NOTFOUND; } n = res_nsearch(res, name, C_IN, type, buf->buf, sizeof(buf->buf)); if (n < 0) { free(buf); dprintf("res_nsearch failed (%d)\n", res, n); __res_put_state(res); return NS_NOTFOUND; } hp = getanswer(buf, n, name, type, res); free(buf); __res_put_state(res); if (hp == NULL) switch (h_errno) { case HOST_NOT_FOUND: return NS_NOTFOUND; case TRY_AGAIN: return NS_TRYAGAIN; default: return NS_UNAVAIL; } *((struct hostent **)rv) = hp; return NS_SUCCESS; } /*ARGSUSED*/ int _dns_gethtbyaddr(void *rv, void *cb_data, va_list ap) { char qbuf[MAXDNAME + 1], *qp, *ep; int n; querybuf *buf; struct hostent *hp; const unsigned char *uaddr; int len, af, advance; res_state res; _DIAGASSERT(rv != NULL); uaddr = va_arg(ap, unsigned char *); len = va_arg(ap, int); af = va_arg(ap, int); switch (af) { case AF_INET: (void)snprintf(qbuf, sizeof(qbuf), "%u.%u.%u.%u.in-addr.arpa", (uaddr[3] & 0xff), (uaddr[2] & 0xff), (uaddr[1] & 0xff), (uaddr[0] & 0xff)); break; case AF_INET6: qp = qbuf; ep = qbuf + sizeof(qbuf) - 1; for (n = IN6ADDRSZ - 1; n >= 0; n--) { advance = snprintf(qp, (size_t)(ep - qp), "%x.%x.", uaddr[n] & 0xf, ((unsigned int)uaddr[n] >> 4) & 0xf); if (advance > 0 && qp + advance < ep) qp += advance; else { h_errno = NETDB_INTERNAL; return NS_NOTFOUND; } } if (strlcat(qbuf, "ip6.arpa", sizeof(qbuf)) >= sizeof(qbuf)) { h_errno = NETDB_INTERNAL; return NS_NOTFOUND; } break; default: abort(); } buf = malloc(sizeof(*buf)); if (buf == NULL) { h_errno = NETDB_INTERNAL; return NS_NOTFOUND; } res = __res_get_state(); if (res == NULL) { free(buf); return NS_NOTFOUND; } n = res_nquery(res, qbuf, C_IN, T_PTR, buf->buf, sizeof(buf->buf)); if (n < 0) { free(buf); dprintf("res_nquery failed (%d)\n", res, n); __res_put_state(res); return NS_NOTFOUND; } hp = getanswer(buf, n, qbuf, T_PTR, res); free(buf); if (hp == NULL) { __res_put_state(res); switch (h_errno) { case HOST_NOT_FOUND: return NS_NOTFOUND; case TRY_AGAIN: return NS_TRYAGAIN; default: return NS_UNAVAIL; } } hp->h_addrtype = af; hp->h_length = len; (void)memcpy(host_addr, uaddr, (size_t)len); h_addr_ptrs[0] = (char *)(void *)host_addr; h_addr_ptrs[1] = NULL; if (af == AF_INET && (res->options & RES_USE_INET6)) { map_v4v6_address((char *)(void *)host_addr, (char *)(void *)host_addr); hp->h_addrtype = AF_INET6; hp->h_length = IN6ADDRSZ; } __res_put_state(res); *((struct hostent **)rv) = hp; h_errno = NETDB_SUCCESS; return NS_SUCCESS; } #ifdef YP /*ARGSUSED*/ struct hostent * _yphostent(char *line, int af) { static struct in_addr host_addrs[MAXADDRS]; static struct in6_addr host6_addrs[MAXADDRS]; char *p = line; char *cp, **q; char **hap; int addrok; int more; size_t naddrs; _DIAGASSERT(line != NULL); host.h_name = NULL; host.h_addr_list = h_addr_ptrs; host.h_addrtype = af; switch (af) { case AF_INET: host.h_length = INADDRSZ; break; case AF_INET6: host.h_length = IN6ADDRSZ; break; default: return NULL; } hap = h_addr_ptrs; q = host.h_aliases = host_aliases; naddrs = 0; nextline: /* check for host_addrs overflow */ if (naddrs >= sizeof(host_addrs) / sizeof(host_addrs[0])) goto done; if (naddrs >= sizeof(host6_addrs) / sizeof(host6_addrs[0])) goto done; more = 0; cp = strpbrk(p, " \t"); if (cp == NULL) goto done; *cp++ = '\0'; /* p has should have an address */ addrok = 0; switch (af) { case AF_INET: addrok = inet_aton(p, &host_addrs[naddrs]); break; case AF_INET6: addrok = inet_pton(af, p, &host6_addrs[naddrs]); break; } if (addrok != 1) { /* skip to the next line */ while (cp && *cp) { if (*cp == '\n') { cp++; goto nextline; } cp++; } goto done; } switch (af) { case AF_INET: *hap++ = (char *)(void *)&host_addrs[naddrs++]; break; case AF_INET6: *hap++ = (char *)(void *)&host6_addrs[naddrs++]; break; } while (*cp == ' ' || *cp == '\t') cp++; p = cp; cp = strpbrk(p, " \t\n"); if (cp != NULL) { if (*cp == '\n') more = 1; *cp++ = '\0'; } if (!host.h_name) host.h_name = p; else if (strcmp(host.h_name, p)==0) ; else if (q < &host_aliases[MAXALIASES - 1]) *q++ = p; p = cp; if (more) goto nextline; while (cp && *cp) { if (*cp == ' ' || *cp == '\t') { cp++; continue; } if (*cp == '\n') { cp++; goto nextline; } if (q < &host_aliases[MAXALIASES - 1]) *q++ = cp; cp = strpbrk(cp, " \t"); if (cp != NULL) *cp++ = '\0'; } done: if (host.h_name == NULL) return NULL; *q = NULL; *hap = NULL; return &host; } /*ARGSUSED*/ int _yp_gethtbyaddr(void *rv, void *cb_data, va_list ap) { struct hostent *hp = NULL; static char *__ypcurrent; int __ypcurrentlen, r; char name[INET6_ADDRSTRLEN]; /* XXX enough? */ const unsigned char *uaddr; int af; const char *map; _DIAGASSERT(rv != NULL); uaddr = va_arg(ap, unsigned char *); /* NOSTRICT skip len */(void)va_arg(ap, int); af = va_arg(ap, int); if (!__ypdomain) { if (_yp_check(&__ypdomain) == 0) return NS_UNAVAIL; } /* * XXX unfortunately, we cannot support IPv6 extended scoped address * notation here. gethostbyaddr() is not scope-aware. too bad. */ if (inet_ntop(af, uaddr, name, sizeof(name)) == NULL) return NS_UNAVAIL; if (__ypcurrent) free(__ypcurrent); __ypcurrent = NULL; switch (af) { case AF_INET: map = "hosts.byaddr"; break; default: map = "ipnodes.byaddr"; break; } r = yp_match(__ypdomain, map, name, (int)strlen(name), &__ypcurrent, &__ypcurrentlen); if (r == 0) hp = _yphostent(__ypcurrent, af); if (hp == NULL) { h_errno = HOST_NOT_FOUND; return NS_NOTFOUND; } *((struct hostent **)rv) = hp; return NS_SUCCESS; } /*ARGSUSED*/ int _yp_gethtbyname(void *rv, void *cb_data, va_list ap) { struct hostent *hp = NULL; static char *__ypcurrent; int __ypcurrentlen, r; const char *name; int af; const char *map; _DIAGASSERT(rv != NULL); name = va_arg(ap, char *); /* NOSTRICT skip len */(void)va_arg(ap, int); af = va_arg(ap, int); if (!__ypdomain) { if (_yp_check(&__ypdomain) == 0) return NS_UNAVAIL; } if (__ypcurrent) free(__ypcurrent); __ypcurrent = NULL; switch (af) { case AF_INET: map = "hosts.byname"; break; default: map = "ipnodes.byname"; break; } r = yp_match(__ypdomain, map, name, (int)strlen(name), &__ypcurrent, &__ypcurrentlen); if (r == 0) hp = _yphostent(__ypcurrent, af); if (hp == NULL) { h_errno = HOST_NOT_FOUND; return NS_NOTFOUND; } *((struct hostent **)rv) = hp; return NS_SUCCESS; } #endif