usr/src/cmd/ipf/lib/common/genmask.c

   1 /*
   2  * Copyright (C) 1993-2001 by Darren Reed.
   3  *
   4  * See the IPFILTER.LICENCE file for details on licencing.
   5  *
   6  * $Id: genmask.c,v 1.7 2003/11/11 13:40:15 darrenr Exp $
   7  */
   8
   9 #include "ipf.h"
  10
  11
  12 int genmask(msk, mskp)
  13 char *msk;
  14 u_32_t *mskp;
  15 {
  16         char *endptr = 0L;
  17         int bits;
  18
  19         if (strchr(msk, '.') || strchr(msk, 'x') || strchr(msk, ':')) {
  20                 /* possibly of the form xxx.xxx.xxx.xxx
  21                  * or 0xYYYYYYYY */
  22 #ifdef  USE_INET6
  23                 if (use_inet6) {
  24                         if (inet_pton(AF_INET6, msk, mskp) != 1)
  25                                 return -1;
  26                 } else
  27 #endif
  28                 if (inet_aton(msk, (struct in_addr *)mskp) == 0)
  29                         return -1;
  30         } else {
  31                 /*
  32                  * set x most significant bits
  33                  */
  34                 bits = (int)strtol(msk, &endptr, 0);
  35 #ifdef  USE_INET6
  36                 if ((*endptr != '\0') ||
  37                     ((bits > 32) && !use_inet6) || (bits < 0) ||
  38                     ((bits > 128) && use_inet6))
  39 #else
  40                 if (*endptr != '\0' || bits > 32 || bits < 0)
  41 #endif
  42                         return -1;
  43 #ifdef  USE_INET6
  44                 if (use_inet6)
  45                         fill6bits(bits, mskp);
  46                 else
  47 #endif
  48                 if (bits == 0)
  49                         *mskp = 0;
  50                 else
  51                         *mskp = htonl(0xffffffff << (32 - bits));
  52         }
  53         return 0;
  54 }