StdLib/BsdSocketLib/gethostbyht.c

   1 /*-
   2  * Copyright (c) 1985, 1988, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Portions copyright (c) 1999, 2000
   6  * Intel Corporation.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  *
  20  * 3. All advertising materials mentioning features or use of this software
  21  *    must display the following acknowledgement:
  22  *
  23  *    This product includes software developed by the University of
  24  *    California, Berkeley, Intel Corporation, and its contributors.
  25  *
  26  * 4. Neither the name of University, Intel Corporation, or their respective
  27  *    contributors may be used to endorse or promote products derived from
  28  *    this software without specific prior written permission.
  29  *
  30  * THIS SOFTWARE IS PROVIDED BY THE REGENTS, INTEL CORPORATION AND
  31  * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
  32  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  33  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS,
  34  * INTEL CORPORATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  35  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  36  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  37  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  38  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  39  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  40  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  41  *
  42  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
  43  *
  44  * Permission to use, copy, modify, and distribute this software for any
  45  * purpose with or without fee is hereby granted, provided that the above
  46  * copyright notice and this permission notice appear in all copies, and that
  47  * the name of Digital Equipment Corporation not be used in advertising or
  48  * publicity pertaining to distribution of the document or software without
  49  * specific, written prior permission.
  50  *
  51  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
  52  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
  53  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
  54  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  55  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  56  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  57  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  58  * SOFTWARE.
  59  * -
  60  * --Copyright--
  61  */
  62
  63 #if defined(LIBC_SCCS) && !defined(lint)
  64 static char sccsid[] = "@(#)gethostnamadr.c     8.1 (Berkeley) 6/4/93";
  65 static char rcsid[] = "$Id: gethostbyht.c,v 1.1.1.1 2003/11/19 01:51:27 kyu3 Exp $";
  66 #endif /* LIBC_SCCS and not lint */
  67
  68 #include <sys/param.h>
  69 #include <sys/socket.h>
  70 #include <netinet/in.h>
  71 #include <arpa/inet.h>
  72 #include <netdb.h>
  73 #include <stdio.h>
  74 #include <ctype.h>
  75 #include <errno.h>
  76 #include <string.h>
  77 #include <arpa/nameser.h>       /* XXX */
  78 #include <resolv.h>             /* XXX */
  79 #include "Socklib_internals.h"
  80
  81 #define MAXALIASES      35
  82
  83 static struct hostent host;
  84 static char *host_aliases[MAXALIASES];
  85 static char hostbuf[BUFSIZ+1];
  86 static FILE *hostf = NULL;
  87 static u_char host_addr[16];    /* IPv4 or IPv6 */
  88 static char *h_addr_ptrs[2];
  89 static int stayopen = 0;
  90
  91 void
  92 _sethosthtent(int f)
  93 {
  94         if (!hostf)
  95                 hostf = fopen(_PATH_HOSTS, "r" );
  96         else
  97                 rewind(hostf);
  98         stayopen = f;
  99 }
 100
 101 void
 102 _endhosthtent()
 103 {
 104         if (hostf && !stayopen) {
 105                 (void) fclose(hostf);
 106                 hostf = NULL;
 107         }
 108 }
 109
 110 struct hostent *
 111 gethostent()
 112 {
 113         char *p;
 114         register char *cp, **q;
 115         int af, len;
 116
 117         if (!hostf && ( NULL == (hostf = fopen(_PATH_HOSTS, "r" )))) {
 118                 h_errno = NETDB_INTERNAL;
 119                 return (NULL);
 120         }
 121  again:
 122         if ( NULL == (p = fgets(hostbuf, sizeof hostbuf, hostf))) {
 123                 h_errno = HOST_NOT_FOUND;
 124                 return (NULL);
 125         }
 126         if (*p == '#')
 127                 goto again;
 128         if ( NULL == (cp = strpbrk(p, "#\n")))
 129                 goto again;
 130         *cp = '\0';
 131         if ( NULL == (cp = strpbrk(p, " \t")))
 132                 goto again;
 133         *cp++ = '\0';
 134         if (inet_pton(AF_INET6, p, host_addr) > 0) {
 135                 af = AF_INET6;
 136                 len = IN6ADDRSZ;
 137         } else if (inet_pton(AF_INET, p, host_addr) > 0) {
 138                 if (_res.options & RES_USE_INET6) {
 139                         _map_v4v6_address((char*)host_addr, (char*)host_addr);
 140                         af = AF_INET6;
 141                         len = IN6ADDRSZ;
 142                 } else {
 143                         af = AF_INET;
 144                         len = INADDRSZ;
 145                 }
 146         } else {
 147                 goto again;
 148         }
 149         h_addr_ptrs[0] = (char *)host_addr;
 150         h_addr_ptrs[1] = NULL;
 151         host.h_addr_list = h_addr_ptrs;
 152         host.h_length = len;
 153         host.h_addrtype = af;
 154         while (*cp == ' ' || *cp == '\t')
 155                 cp++;
 156         host.h_name = cp;
 157         q = host.h_aliases = host_aliases;
 158         if ((cp = strpbrk(cp, " \t\r")) != NULL)
 159                 *cp++ = '\0';
 160         while (cp && *cp) {
 161                 if (*cp == ' ' || *cp == '\t') {
 162                         cp++;
 163                         continue;
 164                 }
 165                 if (q < &host_aliases[MAXALIASES - 1])
 166                         *q++ = cp;
 167                 if ((cp = strpbrk(cp, " \t\r")) != NULL)
 168                         *cp++ = '\0';
 169         }
 170         *q = NULL;
 171         h_errno = NETDB_SUCCESS;
 172         return (&host);
 173 }
 174
 175 struct hostent *
 176 _gethostbyhtname(const char *name, int af)
 177 {
 178         register struct hostent *p;
 179         register char **cp;
 180
 181         sethostent(0);
 182         while ((p = gethostent()) != NULL) {
 183                 if (p->h_addrtype != af)
 184                         continue;
 185                 if (strcasecmp(p->h_name, name) == 0)
 186                         break;
 187                 for (cp = p->h_aliases; *cp != 0; cp++)
 188                         if (strcasecmp(*cp, name) == 0)
 189                                 goto found;
 190         }
 191 found:
 192         endhostent();
 193         return (p);
 194 }
 195
 196 struct hostent *
 197 _gethostbyhtaddr(const char *addr, int len, int af)
 198 {
 199         register struct hostent *p;
 200
 201         sethostent(0);
 202         while ((p = gethostent()) != NULL)
 203                 if (p->h_addrtype == af && !bcmp(p->h_addr, addr, len))
 204                         break;
 205         endhostent();
 206         return (p);
 207 }