lib/libc/net/inet_addr.c

   1 /*      $KAME: inet_addr.c,v 1.5 2001/08/20 02:32:40 itojun Exp $       */
   2
   3 /*
   4  * ++Copyright++ 1983, 1990, 1993
   5  * -
   6  * Copyright (c) 1983, 1990, 1993
   7  *    The Regents of the University of California.  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  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  * -
  33  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
  34  *
  35  * Permission to use, copy, modify, and distribute this software for any
  36  * purpose with or without fee is hereby granted, provided that the above
  37  * copyright notice and this permission notice appear in all copies, and that
  38  * the name of Digital Equipment Corporation not be used in advertising or
  39  * publicity pertaining to distribution of the document or software without
  40  * specific, written prior permission.
  41  *
  42  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
  43  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
  44  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
  45  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  46  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  47  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  48  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  49  * SOFTWARE.
  50  * -
  51  * --Copyright--
  52  *
  53  * @(#)inet_addr.c      8.1 (Berkeley) 6/17/93
  54  * $FreeBSD: src/lib/libc/net/inet_addr.c,v 1.12.2.2 2002/04/28 05:40:24 suz Exp $
  55  * $DragonFly: src/lib/libc/net/inet_addr.c,v 1.5 2005/11/13 02:04:47 swildner Exp $
  56  */
  57
  58 #include <sys/param.h>
  59
  60 #include <netinet/in.h>
  61 #include <arpa/inet.h>
  62
  63 #include <ctype.h>
  64 #include <errno.h>
  65 #include <string.h>
  66 #include <stdlib.h>
  67
  68 /*
  69  * ASCII internet address interpretation routine.
  70  * The value returned is in network order.
  71  */
  72 in_addr_t               /* XXX should be struct in_addr :( */
  73 inet_addr(const char *cp)
  74 {
  75         struct in_addr val;
  76
  77         if (inet_aton(cp, &val))
  78                 return (val.s_addr);
  79         return (INADDR_NONE);
  80 }
  81
  82 /*
  83  * Check whether "cp" is a valid ASCII representation
  84  * of an Internet address and convert to a binary address.
  85  * Returns 1 if the address is valid, 0 if not.
  86  * This replaces inet_addr, the return value from which
  87  * cannot distinguish between failure and a local broadcast address.
  88  */
  89 int
  90 inet_aton(const char *cp, struct in_addr *addr)
  91 {
  92         u_long parts[4];
  93         in_addr_t val;
  94         char *c;
  95         char *endptr;
  96         int gotend, n;
  97
  98         c = (char *)cp;
  99         n = 0;
 100         /*
 101          * Run through the string, grabbing numbers until
 102          * the end of the string, or some error
 103          */
 104         gotend = 0;
 105         while (!gotend) {
 106                 errno = 0;
 107                 val = strtoul(c, &endptr, 0);
 108
 109                 if (errno == ERANGE)    /* Fail completely if it overflowed. */
 110                         return (0);
 111
 112                 /*
 113                  * If the whole string is invalid, endptr will equal
 114                  * c.. this way we can make sure someone hasn't
 115                  * gone '.12' or something which would get past
 116                  * the next check.
 117                  */
 118                 if (endptr == c)
 119                         return (0);
 120                 parts[n] = val;
 121                 c = endptr;
 122
 123                 /* Check the next character past the previous number's end */
 124                 switch (*c) {
 125                 case '.' :
 126                         /* Make sure we only do 3 dots .. */
 127                         if (n == 3)     /* Whoops. Quit. */
 128                                 return (0);
 129                         n++;
 130                         c++;
 131                         break;
 132
 133                 case '\0':
 134                         gotend = 1;
 135                         break;
 136
 137                 default:
 138                         if (isspace((unsigned char)*c)) {
 139                                 gotend = 1;
 140                                 break;
 141                         } else
 142                                 return (0);     /* Invalid character, so fail */
 143                 }
 144
 145         }
 146
 147         /*
 148          * Concoct the address according to
 149          * the number of parts specified.
 150          */
 151
 152         switch (n) {
 153         case 0:                         /* a -- 32 bits */
 154                 /*
 155                  * Nothing is necessary here.  Overflow checking was
 156                  * already done in strtoul().
 157                  */
 158                 break;
 159         case 1:                         /* a.b -- 8.24 bits */
 160                 if (val > 0xffffff || parts[0] > 0xff)
 161                         return (0);
 162                 val |= parts[0] << 24;
 163                 break;
 164
 165         case 2:                         /* a.b.c -- 8.8.16 bits */
 166                 if (val > 0xffff || parts[0] > 0xff || parts[1] > 0xff)
 167                         return (0);
 168                 val |= (parts[0] << 24) | (parts[1] << 16);
 169                 break;
 170
 171         case 3:                         /* a.b.c.d -- 8.8.8.8 bits */
 172                 if (val > 0xff || parts[0] > 0xff || parts[1] > 0xff ||
 173                     parts[2] > 0xff)
 174                         return (0);
 175                 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
 176                 break;
 177         }
 178
 179         if (addr != NULL)
 180                 addr->s_addr = htonl(val);
 181         return (1);
 182 }
 183
 184 /*
 185  * Weak aliases for applications that use certain private entry points,
 186  * and fail to include <arpa/inet.h>.
 187  */
 188 #undef inet_addr
 189 __weak_reference(__inet_addr, inet_addr);
 190 #undef inet_aton
 191 __weak_reference(__inet_aton, inet_aton);