wsutil/inet_aton.c

   1 /*
   2  * $Id$
   3  *
   4  * Copyright (c) 1983, 1990, 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 "config.h"
  33
  34 #if defined(LIBC_SCCS) && !defined(lint)
  35 static char sccsid[] = "@(#)inet_addr.c 8.1 (Berkeley) 6/17/93";
  36 #endif /* LIBC_SCCS and not lint */
  37
  38 #ifdef HAVE_SYS_PARAM_H
  39 #include <sys/param.h>
  40 #endif
  41
  42 #ifdef HAVE_NETINET_IN_H
  43 #include <netinet/in.h>
  44 #endif
  45
  46 #ifdef HAVE_WINSOCK2_H
  47 #include <winsock2.h>
  48 #endif
  49
  50 #ifdef HAVE_ARPA_INET_H
  51 #include <arpa/inet.h>
  52 #endif
  53
  54 #include <ctype.h>
  55
  56 #include "inet_aton.h"
  57
  58 /*
  59  * Check whether "cp" is a valid ascii representation
  60  * of an Internet address and convert to a binary address.
  61  * Returns 1 if the address is valid, 0 if not.
  62  * This replaces inet_addr, the return value from which
  63  * cannot distinguish between failure and a local broadcast address.
  64  */
  65 int
  66 inet_aton(cp_arg, addr)
  67         const char *cp_arg;
  68         struct in_addr *addr;
  69 {
  70         register const u_char *cp = cp_arg;
  71         register u_long val;
  72         register int base;
  73         register size_t n;
  74         register u_char c;
  75         u_int parts[4];
  76         register u_int *pp = parts;
  77
  78         for (;;) {
  79                 /*
  80                  * Collect number up to ``.''.
  81                  * Values are specified as for C:
  82                  * 0x=hex, 0=octal, other=decimal.
  83                  */
  84                 val = 0; base = 10;
  85                 if (*cp == '0') {
  86                         if (*++cp == 'x' || *cp == 'X')
  87                                 base = 16, cp++;
  88                         else
  89                                 base = 8;
  90                 }
  91                 while ((c = *cp) != '\0') {
  92                         if (isascii(c) && isdigit(c)) {
  93                                 val = (val * base) + (c - '0');
  94                                 cp++;
  95                                 continue;
  96                         }
  97                         if (base == 16 && isascii(c) && isxdigit(c)) {
  98                                 val = (val << 4) +
  99                                         (c + 10 - (islower(c) ? 'a' : 'A'));
 100                                 cp++;
 101                                 continue;
 102                         }
 103                         break;
 104                 }
 105                 if (*cp == '.') {
 106                         /*
 107                          * Internet format:
 108                          *      a.b.c.d
 109                          *      a.b.c   (with c treated as 16-bits)
 110                          *      a.b     (with b treated as 24 bits)
 111                          */
 112                         if (pp >= parts + 3 || val > 0xff)
 113                                 return (0);
 114                         *pp++ = val, cp++;
 115                 } else
 116                         break;
 117         }
 118         /*
 119          * Check for trailing characters.
 120          */
 121         if (*cp && (!isascii(*cp) || !isspace(*cp)))
 122                 return (0);
 123         /*
 124          * Concoct the address according to
 125          * the number of parts specified.
 126          */
 127         n = pp - parts + 1;
 128         switch (n) {
 129
 130         case 1:                         /* a -- 32 bits */
 131                 break;
 132
 133         case 2:                         /* a.b -- 8.24 bits */
 134                 if (val > 0xffffff)
 135                         return (0);
 136                 val |= parts[0] << 24;
 137                 break;
 138
 139         case 3:                         /* a.b.c -- 8.8.16 bits */
 140                 if (val > 0xffff)
 141                         return (0);
 142                 val |= (parts[0] << 24) | (parts[1] << 16);
 143                 break;
 144
 145         case 4:                         /* a.b.c.d -- 8.8.8.8 bits */
 146                 if (val > 0xff)
 147                         return (0);
 148                 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
 149                 break;
 150         }
 151         if (addr)
 152                 addr->s_addr = htonl(val);
 153         return (1);
 154 }