/* $NetBSD: gethost.c,v 1.12 2013/12/21 20:10:02 christos Exp $ */ /*- * 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-- */ /* Provide just /etc/hosts lookup support */ #include #ifdef __weak_alias #define gethostbyaddr _gethostbyaddr #define gethostbyname _gethostbyname #endif #include #include #include #include #include #include #include #include "hostent.h" #ifdef __weak_alias __weak_alias(gethostbyaddr,_gethostbyaddr); __weak_alias(gethostbyname,_gethostbyname); #endif int h_errno; FILE *_h_file; static struct hostent h_ent; static char h_buf[4096]; static struct hostent * getby(int (*f)(void *, void *, va_list), struct getnamaddr *info, ...) { va_list ap; int e; va_start(ap, info); e = (*f)(info, NULL, ap); va_end(ap); switch (e) { case NS_SUCCESS: return info->hp; default: return NULL; } } struct hostent * gethostbyname_r(const char *name, struct hostent *hp, char *buf, size_t bufsiz, int *he) { struct getnamaddr info; info.hp = hp; info.buf = buf; info.buflen = bufsiz; info.he = he; return getby(_hf_gethtbyname, &info, name, 0, AF_INET); } struct hostent * gethostbyname(const char *name) { return gethostbyname_r(name, &h_ent, h_buf, sizeof(h_buf), &h_errno); } struct hostent * gethostbyaddr_r(const void *addr, socklen_t len, int type, struct hostent *hp, char *buf, size_t bufsiz, int *he) { struct getnamaddr info; info.hp = hp; info.buf = buf; info.buflen = bufsiz; info.he = he; return getby(_hf_gethtbyaddr, &info, addr, len, type); } struct hostent * gethostbyaddr(const void *addr, socklen_t len, int type) { return gethostbyaddr_r(addr, len, type, &h_ent, h_buf, sizeof(h_buf), &h_errno); } struct hostent * gethostent_r(FILE *hf, struct hostent *hent, char *buf, size_t buflen, int *he) { char *p, *name; char *cp, **q; int af, len; size_t llen, anum; char *aliases[MAXALIASES]; struct in6_addr host_addr; if (hf == NULL) { *he = NETDB_INTERNAL; errno = EINVAL; return NULL; } again: if ((p = fgetln(hf, &llen)) == NULL) { *he = HOST_NOT_FOUND; return NULL; } if (llen < 1) goto again; if (*p == '#') goto again; p[llen] = '\0'; if (!(cp = strpbrk(p, "#\n"))) goto again; *cp = '\0'; if (!(cp = strpbrk(p, " \t"))) goto again; *cp++ = '\0'; if (inet_pton(AF_INET6, p, &host_addr) > 0) { af = AF_INET6; len = NS_IN6ADDRSZ; } else if (inet_pton(AF_INET, p, &host_addr) > 0) { #if 0 res_state res = __res_get_state(); if (res == NULL) return NULL; if (res->options & RES_USE_INET6) { map_v4v6_address(buf, buf); af = AF_INET6; len = NS_IN6ADDRSZ; } else { #endif af = AF_INET; len = NS_INADDRSZ; #if 0 } __res_put_state(res); #endif } else { goto again; } /* if this is not something we're looking for, skip it. */ if (hent->h_addrtype != 0 && hent->h_addrtype != af) goto again; if (hent->h_length != 0 && hent->h_length != len) goto again; while (*cp == ' ' || *cp == '\t') cp++; if ((cp = strpbrk(name = cp, " \t")) != NULL) *cp++ = '\0'; q = aliases; while (cp && *cp) { if (*cp == ' ' || *cp == '\t') { cp++; continue; } if (q >= &aliases[__arraycount(aliases)]) goto nospc; *q++ = cp; if ((cp = strpbrk(cp, " \t")) != NULL) *cp++ = '\0'; } hent->h_length = len; hent->h_addrtype = af; HENT_ARRAY(hent->h_addr_list, 1, buf, buflen); anum = (size_t)(q - aliases); HENT_ARRAY(hent->h_aliases, anum, buf, buflen); HENT_COPY(hent->h_addr_list[0], &host_addr, hent->h_length, buf, buflen); hent->h_addr_list[1] = NULL; HENT_SCOPY(hent->h_name, name, buf, buflen); for (size_t i = 0; i < anum; i++) HENT_SCOPY(hent->h_aliases[i], aliases[i], buf, buflen); hent->h_aliases[anum] = NULL; *he = NETDB_SUCCESS; return hent; nospc: errno = ENOSPC; *he = NETDB_INTERNAL; return NULL; }