/**************************************************************************************************
$Id: cidr.c,v 1.6 2005/04/20 16:49:11 bboy Exp $
Copyright (C) 2002-2005 Don Moore <bboy@bboy.net>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at Your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
**************************************************************************************************/
#include "mydnsutil.h"
/**************************************************************************************************
IN_CIDR
Checks to see if the specified IP address is within the specified CIDR range.
XXX: Fix to work with IPv6
Returns 1 if so, 0 if not.
**************************************************************************************************/
int
in_cidr(char *cidr, struct in_addr ip)
{
unsigned int tmp[8];
struct in_addr network, netmask;
network.s_addr = 0;
netmask.s_addr = 0;
if (sscanf(cidr, "%u.%u.%u.%u/%u.%u.%u.%u",
&tmp[0], &tmp[1], &tmp[2], &tmp[3], &tmp[4], &tmp[5], &tmp[6], &tmp[7]) == 8)
{
network.s_addr = htonl((tmp[0] << 24) + (tmp[1] << 16) + (tmp[2] << 8) + tmp[3]);
netmask.s_addr = htonl((tmp[4] << 24) + (tmp[5] << 16) + (tmp[6] << 8) + tmp[7]);
}
else if (sscanf(cidr, "%u.%u.%u.%u/%u", &tmp[0], &tmp[1], &tmp[2], &tmp[3], &tmp[4]) == 5)
{
network.s_addr = htonl((tmp[0] << 24) + (tmp[1] << 16) + (tmp[2] << 8) + tmp[3]);
while (tmp[4] > 0)
{
netmask.s_addr = (netmask.s_addr >> 1) + 0x80000000;
tmp[4]--;
}
netmask.s_addr = htonl(netmask.s_addr);
}
else return (0);
return ((ip.s_addr & netmask.s_addr) == (network.s_addr & netmask.s_addr));
}
/*--- in_cidr() ---------------------------------------------------------------------------------*/
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