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/*
* ebt_ip
*
* Authors:
* Bart De Schuymer <bart.de.schuymer@pandora.be>
*
* April, 2002
*
*/
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_ip.h>
#include <linux/ip.h>
#include <linux/module.h>
static int ebt_filter_ip(const struct sk_buff *skb, const struct net_device *in,
const struct net_device *out, const void *data,
unsigned int datalen)
{
struct ebt_ip_info *info = (struct ebt_ip_info *)data;
if (info->bitmask & EBT_IP_TOS &&
FWINV(info->tos != ((*skb).nh.iph)->tos, EBT_IP_TOS))
return EBT_NOMATCH;
if (info->bitmask & EBT_IP_PROTO && FWINV(info->protocol !=
((*skb).nh.iph)->protocol, EBT_IP_PROTO))
return EBT_NOMATCH;
if (info->bitmask & EBT_IP_SOURCE &&
FWINV((((*skb).nh.iph)->saddr & info->smsk) !=
info->saddr, EBT_IP_SOURCE))
return EBT_NOMATCH;
if ((info->bitmask & EBT_IP_DEST) &&
FWINV((((*skb).nh.iph)->daddr & info->dmsk) !=
info->daddr, EBT_IP_DEST))
return EBT_NOMATCH;
return EBT_MATCH;
}
static int ebt_ip_check(const char *tablename, unsigned int hookmask,
const struct ebt_entry *e, void *data, unsigned int datalen)
{
struct ebt_ip_info *info = (struct ebt_ip_info *)data;
if (datalen != sizeof(struct ebt_ip_info))
return -EINVAL;
if (e->ethproto != __constant_htons(ETH_P_IP) ||
e->invflags & EBT_IPROTO)
return -EINVAL;
if (info->bitmask & ~EBT_IP_MASK || info->invflags & ~EBT_IP_MASK)
return -EINVAL;
return 0;
}
static struct ebt_match filter_ip =
{
{NULL, NULL}, EBT_IP_MATCH, ebt_filter_ip, ebt_ip_check, NULL,
THIS_MODULE
};
static int __init init(void)
{
return ebt_register_match(&filter_ip);
}
static void __exit fini(void)
{
ebt_unregister_match(&filter_ip);
}
module_init(init);
module_exit(fini);
EXPORT_NO_SYMBOLS;
MODULE_LICENSE("GPL");
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