lib/libc/net/sethostent.c

   1 /*      $NetBSD: sethostent.c,v 1.19 2013/08/27 09:56:12 christos Exp $ */
   2
   3 /*
   4  * Copyright (c) 1985, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #if defined(LIBC_SCCS) && !defined(lint)
  34 #if 0
  35 static char sccsid[] = "@(#)sethostent.c        8.1 (Berkeley) 6/4/93";
  36 static char rcsid[] = "Id: sethostent.c,v 8.5 1996/09/28 06:51:07 vixie Exp ";
  37 #else
  38 __RCSID("$NetBSD: sethostent.c,v 1.19 2013/08/27 09:56:12 christos Exp $");
  39 #endif
  40 #endif /* LIBC_SCCS and not lint */
  41
  42 #include "namespace.h"
  43 #include <sys/param.h>
  44 #include <netinet/in.h>
  45 #include <arpa/nameser.h>
  46 #include <arpa/inet.h>
  47 #include <assert.h>
  48 #include <string.h>
  49 #include <nsswitch.h>
  50 #include <netdb.h>
  51 #include <resolv.h>
  52 #include <errno.h>
  53 #include <stdlib.h>
  54
  55 #include "hostent.h"
  56
  57 #ifdef __weak_alias
  58 __weak_alias(sethostent,_sethostent)
  59 __weak_alias(endhostent,_endhostent)
  60 #endif
  61
  62 #ifndef _REENTRANT
  63 void    res_close(void);
  64 #endif
  65
  66 static struct hostent *_hf_gethtbyname2(const char *, int, struct getnamaddr *);
  67
  68 void
  69 /*ARGSUSED*/
  70 sethostent(int stayopen)
  71 {
  72 #ifndef _REENTRANT
  73         if ((_res.options & RES_INIT) == 0 && res_init() == -1)
  74                 return;
  75         if (stayopen)
  76                 _res.options |= RES_STAYOPEN | RES_USEVC;
  77 #endif
  78         sethostent_r(&_h_file);
  79 }
  80
  81 void
  82 endhostent(void)
  83 {
  84 #ifndef _REENTRANT
  85         _res.options &= ~(RES_STAYOPEN | RES_USEVC);
  86         res_close();
  87 #endif
  88         endhostent_r(&_h_file);
  89 }
  90 static const char *_h_hosts = _PATH_HOSTS;
  91
  92 void
  93 _hf_sethostsfile(const char *f) {
  94         _h_hosts = f;
  95 }
  96
  97 void
  98 sethostent_r(FILE **hf)
  99 {
 100         if (!*hf)
 101                 *hf = fopen(_h_hosts, "re");
 102         else
 103                 rewind(*hf);
 104 }
 105
 106 void
 107 endhostent_r(FILE **hf)
 108 {
 109         if (*hf) {
 110                 (void)fclose(*hf);
 111                 *hf = NULL;
 112         }
 113 }
 114
 115 /*ARGSUSED*/
 116 int
 117 _hf_gethtbyname(void *rv, void *cb_data, va_list ap)
 118 {
 119         struct hostent *hp;
 120         const char *name;
 121         int af;
 122         struct getnamaddr *info = rv;
 123
 124         _DIAGASSERT(rv != NULL);
 125
 126         name = va_arg(ap, char *);
 127         /* NOSTRICT skip string len */(void)va_arg(ap, int);
 128         af = va_arg(ap, int);
 129
 130 #if 0
 131         {
 132                 res_state res = __res_get_state();
 133                 if (res == NULL)
 134                         return NS_NOTFOUND;
 135                 if (res->options & RES_USE_INET6)
 136                         hp = _hf_gethtbyname2(name, AF_INET6, info);
 137                 else
 138                         hp = NULL;
 139                 if (hp == NULL)
 140                         hp = _hf_gethtbyname2(name, AF_INET, info);
 141                 __res_put_state(res);
 142         }
 143 #else
 144         hp = _hf_gethtbyname2(name, af, info);
 145 #endif
 146         if (hp == NULL) {
 147                 *info->he = HOST_NOT_FOUND;
 148                 return NS_NOTFOUND;
 149         }
 150         return NS_SUCCESS;
 151 }
 152
 153 struct hostent *
 154 _hf_gethtbyname2(const char *name, int af, struct getnamaddr *info)
 155 {
 156         struct hostent *hp, hent;
 157         char *buf, *ptr;
 158         size_t len, anum, num, i;
 159         FILE *hf;
 160         char *aliases[MAXALIASES];
 161         char *addr_ptrs[MAXADDRS];
 162
 163         _DIAGASSERT(name != NULL);
 164
 165         hf = NULL;
 166         sethostent_r(&hf);
 167         if (hf == NULL) {
 168                 errno = EINVAL;
 169                 *info->he = NETDB_INTERNAL;
 170                 return NULL;
 171         }
 172
 173         if ((ptr = buf = malloc(len = info->buflen)) == NULL) {
 174                 *info->he = NETDB_INTERNAL;
 175                 return NULL;
 176         }
 177
 178         anum = 0;               /* XXX: gcc */
 179         hent.h_name = NULL;     /* XXX: gcc */
 180         hent.h_addrtype = 0;    /* XXX: gcc */
 181         hent.h_length = 0;      /* XXX: gcc */
 182
 183         for (num = 0; num < MAXADDRS;) {
 184                 info->hp->h_addrtype = af;
 185                 info->hp->h_length = 0;
 186
 187                 hp = gethostent_r(hf, info->hp, info->buf, info->buflen,
 188                     info->he);
 189                 if (hp == NULL)
 190                         break;
 191
 192                 if (strcasecmp(hp->h_name, name) != 0) {
 193                         char **cp;
 194                         for (cp = hp->h_aliases; *cp != NULL; cp++)
 195                                 if (strcasecmp(*cp, name) == 0)
 196                                         break;
 197                         if (*cp == NULL) continue;
 198                 }
 199
 200                 if (num == 0) {
 201                         hent.h_addrtype = af = hp->h_addrtype;
 202                         hent.h_length = hp->h_length;
 203
 204                         HENT_SCOPY(hent.h_name, hp->h_name, ptr, len);
 205                         for (anum = 0; hp->h_aliases[anum]; anum++) {
 206                                 if (anum >= __arraycount(aliases))
 207                                         goto nospc;
 208                                 HENT_SCOPY(aliases[anum], hp->h_aliases[anum],
 209                                     ptr, len);
 210                         }
 211                         ptr = (void *)ALIGN(ptr);
 212                         if ((size_t)(ptr - buf) >= info->buflen)
 213                                 goto nospc;
 214                 }
 215
 216                 if (num >= __arraycount(addr_ptrs))
 217                         goto nospc;
 218                 HENT_COPY(addr_ptrs[num], hp->h_addr_list[0], hp->h_length, ptr,
 219                     len);
 220                 num++;
 221         }
 222         endhostent_r(&hf);
 223
 224         if (num == 0) {
 225                 *info->he = HOST_NOT_FOUND;
 226                 return NULL;
 227         }
 228
 229         hp = info->hp;
 230         ptr = info->buf;
 231         len = info->buflen;
 232
 233         hp->h_addrtype = hent.h_addrtype;
 234         hp->h_length = hent.h_length;
 235
 236         HENT_ARRAY(hp->h_aliases, anum, ptr, len);
 237         HENT_ARRAY(hp->h_addr_list, num, ptr, len);
 238
 239         for (i = 0; i < num; i++)
 240                 HENT_COPY(hp->h_addr_list[i], addr_ptrs[i], hp->h_length, ptr,
 241                     len);
 242         hp->h_addr_list[num] = NULL;
 243
 244         HENT_SCOPY(hp->h_name, hent.h_name, ptr, len);
 245
 246         for (i = 0; i < anum; i++)
 247                 HENT_SCOPY(hp->h_aliases[i], aliases[i], ptr, len);
 248         hp->h_aliases[anum] = NULL;
 249
 250         return hp;
 251 nospc:
 252         *info->he = NETDB_INTERNAL;
 253         errno = ENOSPC;
 254         return NULL;
 255 }
 256
 257 /*ARGSUSED*/
 258 int
 259 _hf_gethtbyaddr(void *rv, void *cb_data, va_list ap)
 260 {
 261         struct hostent *hp;
 262         const unsigned char *addr;
 263         struct getnamaddr *info = rv;
 264         FILE *hf;
 265
 266         _DIAGASSERT(rv != NULL);
 267
 268         addr = va_arg(ap, unsigned char *);
 269         info->hp->h_length = va_arg(ap, int);
 270         info->hp->h_addrtype = va_arg(ap, int);
 271
 272         hf = NULL;
 273         sethostent_r(&hf);
 274         if (hf == NULL) {
 275                 *info->he = NETDB_INTERNAL;
 276                 return NS_UNAVAIL;
 277         }
 278         while ((hp = gethostent_r(hf, info->hp, info->buf, info->buflen,
 279             info->he)) != NULL)
 280                 if (!memcmp(hp->h_addr_list[0], addr, (size_t)hp->h_length))
 281                         break;
 282         endhostent_r(&hf);
 283
 284         if (hp == NULL) {
 285                 *info->he = HOST_NOT_FOUND;
 286                 return NS_NOTFOUND;
 287         }
 288         return NS_SUCCESS;
 289 }