resolv/inet_addr.c

   1 /*
   2  * Copyright (c) 1983, 1990, 1993
   3  *    The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 /*
  31  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
  32  *
  33  * Permission to use, copy, modify, and distribute this software for any
  34  * purpose with or without fee is hereby granted, provided that the above
  35  * copyright notice and this permission notice appear in all copies, and that
  36  * the name of Digital Equipment Corporation not be used in advertising or
  37  * publicity pertaining to distribution of the document or software without
  38  * specific, written prior permission.
  39  *
  40  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
  41  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
  42  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
  43  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  44  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  45  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  46  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  47  * SOFTWARE.
  48  */
  49
  50 /*
  51  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
  52  *
  53  * Permission to use, copy, modify, and distribute this software for any
  54  * purpose with or without fee is hereby granted, provided that the above
  55  * copyright notice and this permission notice appear in all copies.
  56  *
  57  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
  58  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  59  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
  60  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  61  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  62  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  63  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  64  * SOFTWARE.
  65  */
  66
  67 #if defined(LIBC_SCCS) && !defined(lint)
  68 static const char sccsid[] = "@(#)inet_addr.c   8.1 (Berkeley) 6/17/93";
  69 static const char rcsid[] = "$BINDId: inet_addr.c,v 8.11 1999/10/13 16:39:25 vixie Exp $";
  70 #endif /* LIBC_SCCS and not lint */
  71
  72 #include <sys/types.h>
  73 #include <sys/param.h>
  74
  75 #include <netinet/in.h>
  76 #include <arpa/inet.h>
  77
  78 #include <ctype.h>
  79
  80 #ifdef _LIBC
  81 # include <endian.h>
  82 # include <stdint.h>
  83 # include <stdlib.h>
  84 # include <limits.h>
  85 # include <errno.h>
  86 #endif
  87
  88 /*
  89  * Ascii internet address interpretation routine.
  90  * The value returned is in network order.
  91  */
  92 in_addr_t
  93 inet_addr(const char *cp) {
  94         struct in_addr val;
  95
  96         if (__inet_aton(cp, &val))
  97                 return (val.s_addr);
  98         return (INADDR_NONE);
  99 }
 100
 101 /*
 102  * Check whether "cp" is a valid ascii representation
 103  * of an Internet address and convert to a binary address.
 104  * Returns 1 if the address is valid, 0 if not.
 105  * This replaces inet_addr, the return value from which
 106  * cannot distinguish between failure and a local broadcast address.
 107  */
 108 in_addr_t
 109 __inet_aton(const char *cp, struct in_addr *addr)
 110 {
 111         static const in_addr_t max[4] = { 0xffffffff, 0xffffff, 0xffff, 0xff };
 112         in_addr_t val;
 113 #ifndef _LIBC
 114         int base;
 115 #endif
 116         char c;
 117         union iaddr {
 118           uint8_t bytes[4];
 119           uint32_t word;
 120         } res;
 121         uint8_t *pp = res.bytes;
 122         int digit;
 123
 124 #ifdef _LIBC
 125         int saved_errno = errno;
 126         __set_errno (0);
 127 #endif
 128
 129         res.word = 0;
 130
 131         c = *cp;
 132         for (;;) {
 133                 /*
 134                  * Collect number up to ``.''.
 135                  * Values are specified as for C:
 136                  * 0x=hex, 0=octal, isdigit=decimal.
 137                  */
 138                 if (!isdigit(c))
 139                         goto ret_0;
 140 #ifdef _LIBC
 141                 {
 142                         char *endp;
 143                         unsigned long ul = strtoul (cp, (char **) &endp, 0);
 144                         if (ul == ULONG_MAX && errno == ERANGE)
 145                                 goto ret_0;
 146                         if (ul > 0xfffffffful)
 147                                 goto ret_0;
 148                         val = ul;
 149                         digit = cp != endp;
 150                         cp = endp;
 151                 }
 152                 c = *cp;
 153 #else
 154                 val = 0; base = 10; digit = 0;
 155                 if (c == '0') {
 156                         c = *++cp;
 157                         if (c == 'x' || c == 'X')
 158                                 base = 16, c = *++cp;
 159                         else {
 160                                 base = 8;
 161                                 digit = 1 ;
 162                         }
 163                 }
 164                 for (;;) {
 165                         if (isascii(c) && isdigit(c)) {
 166                                 if (base == 8 && (c == '8' || c == '9'))
 167                                         return (0);
 168                                 val = (val * base) + (c - '0');
 169                                 c = *++cp;
 170                                 digit = 1;
 171                         } else if (base == 16 && isascii(c) && isxdigit(c)) {
 172                                 val = (val << 4) |
 173                                         (c + 10 - (islower(c) ? 'a' : 'A'));
 174                                 c = *++cp;
 175                                 digit = 1;
 176                         } else
 177                                 break;
 178                 }
 179 #endif
 180                 if (c == '.') {
 181                         /*
 182                          * Internet format:
 183                          *      a.b.c.d
 184                          *      a.b.c   (with c treated as 16 bits)
 185                          *      a.b     (with b treated as 24 bits)
 186                          */
 187                         if (pp > res.bytes + 2 || val > 0xff)
 188                                 goto ret_0;
 189                         *pp++ = val;
 190                         c = *++cp;
 191                 } else
 192                         break;
 193         }
 194         /*
 195          * Check for trailing characters.
 196          */
 197         if (c != '\0' && (!isascii(c) || !isspace(c)))
 198                 goto ret_0;
 199         /*
 200          * Did we get a valid digit?
 201          */
 202         if (!digit)
 203                 goto ret_0;
 204
 205         /* Check whether the last part is in its limits depending on
 206            the number of parts in total.  */
 207         if (val > max[pp - res.bytes])
 208           goto ret_0;
 209
 210         if (addr != NULL)
 211                 addr->s_addr = res.word | htonl (val);
 212
 213 #ifdef _LIBC
 214         __set_errno (saved_errno);
 215 #endif
 216         return (1);
 217
 218 ret_0:
 219 #ifdef _LIBC
 220         __set_errno (saved_errno);
 221 #endif
 222         return (0);
 223 }
 224 weak_alias (__inet_aton, inet_aton)
 225 libc_hidden_def (__inet_aton)
 226 libc_hidden_weak (inet_aton)