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/*
* ebt_snat
*
* Authors:
* Bart De Schuymer <bart.de.schuymer@pandora.be>
*
* June, 2002
*
*/
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_nat.h>
#include <linux/module.h>
static int ebt_target_snat(struct sk_buff **pskb, unsigned int hooknr,
const struct net_device *in, const struct net_device *out,
const void *data, unsigned int datalen)
{
struct ebt_nat_info *info = (struct ebt_nat_info *) data;
memcpy(((**pskb).mac.ethernet)->h_source, info->mac,
ETH_ALEN * sizeof(unsigned char));
return info->target;
}
static int ebt_target_snat_check(const char *tablename, unsigned int hookmask,
const struct ebt_entry *e, void *data, unsigned int datalen)
{
struct ebt_nat_info *info = (struct ebt_nat_info *) data;
if (datalen != sizeof(struct ebt_nat_info))
return -EINVAL;
if (BASE_CHAIN && info->target == EBT_RETURN)
return -EINVAL;
CLEAR_BASE_CHAIN_BIT;
if (strcmp(tablename, "nat"))
return -EINVAL;
if (hookmask & ~(1 << NF_BR_POST_ROUTING))
return -EINVAL;
if (INVALID_TARGET)
return -EINVAL;
return 0;
}
static struct ebt_target snat =
{
{NULL, NULL}, EBT_SNAT_TARGET, ebt_target_snat, ebt_target_snat_check,
NULL, THIS_MODULE
};
static int __init init(void)
{
return ebt_register_target(&snat);
}
static void __exit fini(void)
{
ebt_unregister_target(&snat);
}
module_init(init);
module_exit(fini);
MODULE_LICENSE("GPL");
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