src/port/inet_aton.c

   1 /* src/port/inet_aton.c
   2  *
   3  *      This inet_aton() function was taken from the GNU C library and
   4  *      incorporated into Postgres for those systems which do not have this
   5  *      routine in their standard C libraries.
   6  *
   7  *      The function was been extracted whole from the file inet_aton.c in
   8  *      Release 5.3.12 of the Linux C library, which is derived from the
   9  *      GNU C library, by Bryan Henderson in October 1996.  The copyright
  10  *      notice from that file is below.
  11  */
  12
  13 /*
  14  * Copyright (c) 1983, 1990, 1993
  15  *              The Regents of the University of California.  All rights reserved.
  16  *
  17  * Redistribution and use in source and binary forms, with or without
  18  * modification, are permitted provided that the following conditions
  19  * are met:
  20  * 1. Redistributions of source code must retain the above copyright
  21  *        notice, this list of conditions and the following disclaimer.
  22  * 2. Redistributions in binary form must reproduce the above copyright
  23  *        notice, this list of conditions and the following disclaimer in the
  24  *        documentation and/or other materials provided with the distribution.
  25  * 3. Neither the name of the University nor the names of its contributors
  26  *        may be used to endorse or promote products derived from this software
  27  *        without specific prior written permission.
  28  *
  29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  39  * SUCH DAMAGE.  */
  40
  41 #include "c.h"
  42
  43 #include <netinet/in.h>
  44 #include <ctype.h>
  45
  46 #include "port/pg_bswap.h"
  47
  48 /*
  49  * Check whether "cp" is a valid ascii representation
  50  * of an Internet address and convert to a binary address.
  51  * Returns 1 if the address is valid, 0 if not.
  52  * This replaces inet_addr, the return value from which
  53  * cannot distinguish between failure and a local broadcast address.
  54  */
  55 int
  56 inet_aton(const char *cp, struct in_addr *addr)
  57 {
  58         unsigned int val;
  59         int                     base,
  60                                 n;
  61         char            c;
  62         u_int           parts[4];
  63         u_int      *pp = parts;
  64
  65         for (;;)
  66         {
  67                 /*
  68                  * Collect number up to ``.''. Values are specified as for C: 0x=hex,
  69                  * 0=octal, other=decimal.
  70                  */
  71                 val = 0;
  72                 base = 10;
  73                 if (*cp == '0')
  74                 {
  75                         if (*++cp == 'x' || *cp == 'X')
  76                                 base = 16, cp++;
  77                         else
  78                                 base = 8;
  79                 }
  80                 while ((c = *cp) != '\0')
  81                 {
  82                         if (isdigit((unsigned char) c))
  83                         {
  84                                 val = (val * base) + (c - '0');
  85                                 cp++;
  86                                 continue;
  87                         }
  88                         if (base == 16 && isxdigit((unsigned char) c))
  89                         {
  90                                 val = (val << 4) +
  91                                         (c + 10 - (islower((unsigned char) c) ? 'a' : 'A'));
  92                                 cp++;
  93                                 continue;
  94                         }
  95                         break;
  96                 }
  97                 if (*cp == '.')
  98                 {
  99                         /*
 100                          * Internet format: a.b.c.d a.b.c       (with c treated as 16-bits)
 101                          * a.b     (with b treated as 24 bits)
 102                          */
 103                         if (pp >= parts + 3 || val > 0xff)
 104                                 return 0;
 105                         *pp++ = val, cp++;
 106                 }
 107                 else
 108                         break;
 109         }
 110
 111         /*
 112          * Check for trailing junk.
 113          */
 114         while (*cp)
 115                 if (!isspace((unsigned char) *cp++))
 116                         return 0;
 117
 118         /*
 119          * Concoct the address according to the number of parts specified.
 120          */
 121         n = pp - parts + 1;
 122         switch (n)
 123         {
 124
 125                 case 1:                                 /* a -- 32 bits */
 126                         break;
 127
 128                 case 2:                                 /* a.b -- 8.24 bits */
 129                         if (val > 0xffffff)
 130                                 return 0;
 131                         val |= parts[0] << 24;
 132                         break;
 133
 134                 case 3:                                 /* a.b.c -- 8.8.16 bits */
 135                         if (val > 0xffff)
 136                                 return 0;
 137                         val |= (parts[0] << 24) | (parts[1] << 16);
 138                         break;
 139
 140                 case 4:                                 /* a.b.c.d -- 8.8.8.8 bits */
 141                         if (val > 0xff)
 142                                 return 0;
 143                         val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
 144                         break;
 145         }
 146         if (addr)
 147                 addr->s_addr = pg_hton32(val);
 148         return 1;
 149 }