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/*
* ebt_nat
*
* Authors:
* Bart De Schuymer <bart.de.schuymer@pandora.be>
*
* April, 2002
*
*/
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_nat.h>
#include <linux/netfilter_bridge.h>
#include <linux/skbuff.h>
#include <linux/module.h>
#include <net/sock.h>
static __u8 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 *infostuff = (struct ebt_nat_info *) data;
memcpy(((**pskb).mac.ethernet)->h_source, infostuff->mac,
ETH_ALEN * sizeof(unsigned char));
return infostuff->target;
}
static __u8 ebt_target_dnat(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 *infostuff = (struct ebt_nat_info *) data;
memcpy(((**pskb).mac.ethernet)->h_dest, infostuff->mac,
ETH_ALEN * sizeof(unsigned char));
return infostuff->target;
}
static int ebt_target_snat_check(const char *tablename, unsigned int hooknr,
const struct ebt_entry *e, void *data, unsigned int datalen)
{
struct ebt_nat_info *infostuff = (struct ebt_nat_info *) data;
if (strcmp(tablename, "nat"))
return -EINVAL;
if (datalen != sizeof(struct ebt_nat_info))
return -EINVAL;
if (hooknr != NF_BR_POST_ROUTING)
return -EINVAL;
if (infostuff->target >= NUM_STANDARD_TARGETS)
return -EINVAL;
return 0;
}
static int ebt_target_dnat_check(const char *tablename, unsigned int hooknr,
const struct ebt_entry *e, void *data, unsigned int datalen)
{
struct ebt_nat_info *infostuff = (struct ebt_nat_info *) data;
if ( (strcmp(tablename, "nat") ||
(hooknr != NF_BR_PRE_ROUTING && hooknr != NF_BR_LOCAL_OUT)) &&
(strcmp(tablename, "broute") || hooknr != NF_BR_BROUTING) )
return -EINVAL;
if (datalen != sizeof(struct ebt_nat_info))
return -EINVAL;
if (infostuff->target >= NUM_STANDARD_TARGETS)
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 struct ebt_target dnat =
{
{NULL, NULL}, EBT_DNAT_TARGET, ebt_target_dnat, ebt_target_dnat_check,
NULL, THIS_MODULE
};
static int __init init(void)
{
int ret;
ret = ebt_register_target(&snat);
if (ret != 0)
return ret;
ret = ebt_register_target(&dnat);
if (ret == 0)
return 0;
ebt_unregister_target(&snat);
return ret;
}
static void __exit fini(void)
{
ebt_unregister_target(&snat);
ebt_unregister_target(&dnat);
}
module_init(init);
module_exit(fini);
EXPORT_NO_SYMBOLS;
MODULE_LICENSE("GPL");
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