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/*
* (C) 2006-2008 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <stdint.h>
#include <string.h>
#include <netinet/in.h>
#include "cidr.h"
/* returns the netmask in host byte order */
uint32_t ipv4_cidr2mask_host(uint8_t cidr)
{
return 0xFFFFFFFF << (32 - cidr);
}
/* returns the netmask in network byte order */
uint32_t ipv4_cidr2mask_net(uint8_t cidr)
{
return htonl(ipv4_cidr2mask_host(cidr));
}
void ipv6_cidr2mask_host(uint8_t cidr, uint32_t *res)
{
int i, j;
memset(res, 0, sizeof(uint32_t)*4);
for (i = 0; i < 4 && cidr > 32; i++) {
res[i] = 0xFFFFFFFF;
cidr -= 32;
}
res[i] = 0xFFFFFFFF << (32 - cidr);
for (j = i+1; j < 4; j++) {
res[j] = 0;
}
}
void ipv6_cidr2mask_net(uint8_t cidr, uint32_t *res)
{
int i;
ipv6_cidr2mask_host(cidr, res);
for (i=0; i<4; i++)
res[i] = htonl(res[i]);
}
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