dist/ipf/lib/alist_new.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2006 by Darren Reed.
   5  *
   6  * See the IPFILTER.LICENCE file for details on licencing.
   7  *
   8  * Id: alist_new.c,v 1.1.2.3 2007/06/06 08:05:33 darrenr Exp
   9  */
  10
  11 #include "ipf.h"
  12
  13 alist_t *
  14 alist_new(int v, char *host)
  15 {
  16         int a, b, c, d, bits;
  17         char *slash;
  18         alist_t *al;
  19         u_int mask;
  20
  21         al = calloc(1, sizeof(*al));
  22         if (al == NULL) {
  23                 fprintf(stderr, "alist_new out of memory\n");
  24                 return NULL;
  25         }
  26
  27         bits = -1;
  28         slash = strchr(host, '/');
  29         if (slash != NULL) {
  30                 *slash = '\0';
  31                 bits = atoi(slash + 1);
  32         }
  33
  34         a = b = c = d = -1;
  35         sscanf(host, "%d.%d.%d.%d", &a, &b, &c, &d);
  36
  37         if (bits > 0 && bits < 33) {
  38                 mask = 0xffffffff << (32 - bits);
  39         } else if (b == -1) {
  40                 mask = 0xff000000;
  41                 b = c = d = 0;
  42         } else if (c == -1) {
  43                 mask = 0xffff0000;
  44                 c = d = 0;
  45         } else if (d == -1) {
  46                 mask = 0xffffff00;
  47                 d = 0;
  48         } else {
  49                 mask = 0xffffffff;
  50         }
  51
  52         if (*host == '!') {
  53                 al->al_not = 1;
  54                 host++;
  55         }
  56
  57         if (gethost(host, &al->al_addr) == -1) {
  58                 if (slash != NULL)
  59                         *slash = '/';
  60                 fprintf(stderr, "Cannot parse hostname\n");
  61                 free(al);
  62                 return NULL;
  63         }
  64         al->al_mask = htonl(mask);
  65         if (slash != NULL)
  66                 *slash = '/';
  67         return al;
  68 }