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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>
#define FWINV2(bool,invflg) ((bool) ^ !!(infostuff->invflags & invflg))
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, const struct ebt_counter *c)
{
struct ebt_ip_info *infostuff = (struct ebt_ip_info *) data;
if (infostuff->bitmask & EBT_IP_TOS &&
FWINV2(infostuff->tos != ((*skb).nh.iph)->tos, EBT_IP_TOS))
return 1;
if (infostuff->bitmask & EBT_IP_PROTO && FWINV2(infostuff->protocol !=
((*skb).nh.iph)->protocol, EBT_IP_PROTO))
return 1;
if (infostuff->bitmask & EBT_IP_SOURCE &&
FWINV2((((*skb).nh.iph)->saddr & infostuff->smsk) !=
infostuff->saddr, EBT_IP_SOURCE))
return 1;
if ((infostuff->bitmask & EBT_IP_DEST) &&
FWINV2((((*skb).nh.iph)->daddr & infostuff->dmsk) !=
infostuff->daddr, EBT_IP_DEST))
return 1;
return 0;
}
static int ebt_ip_check(const char *tablename, unsigned int hooknr,
const struct ebt_entry *e, void *data, unsigned int datalen)
{
struct ebt_ip_info *infostuff = (struct ebt_ip_info *) data;
if (datalen != sizeof(struct ebt_ip_info)) {
return -EINVAL;
}
if (e->bitmask & (EBT_NOPROTO | EBT_802_3) ||
e->ethproto != __constant_htons(ETH_P_IP) ||
e->invflags & EBT_IPROTO)
{
return -EINVAL;
}
if (infostuff->bitmask & ~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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