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/*
* ebt_dnat
*
* Authors:
* Bart De Schuymer <bdschuym@pandora.be>
*
* June, 2002
*
*/
#include <linux/module.h>
#include <net/sock.h>
#include <linux/netfilter.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_nat.h>
static unsigned int
ebt_dnat_tg(struct sk_buff *skb, const struct net_device *in,
const struct net_device *out, unsigned int hook_nr,
const struct xt_target *target, const void *data)
{
const struct ebt_nat_info *info = data;
if (!skb_make_writable(skb, 0))
return EBT_DROP;
memcpy(eth_hdr(skb)->h_dest, info->mac, ETH_ALEN);
return info->target;
}
static bool
ebt_dnat_tg_check(const char *tablename, const void *entry,
const struct xt_target *target, void *data,
unsigned int hookmask)
{
const struct ebt_nat_info *info = data;
if (BASE_CHAIN && info->target == EBT_RETURN)
return false;
CLEAR_BASE_CHAIN_BIT;
if ( (strcmp(tablename, "nat") ||
(hookmask & ~((1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_LOCAL_OUT)))) &&
(strcmp(tablename, "broute") || hookmask & ~(1 << NF_BR_BROUTING)) )
return false;
if (INVALID_TARGET)
return false;
return true;
}
static struct xt_target ebt_dnat_tg_reg __read_mostly = {
.name = "dnat",
.revision = 0,
.family = NFPROTO_BRIDGE,
.hooks = (1 << NF_BR_NUMHOOKS) | (1 << NF_BR_PRE_ROUTING) |
(1 << NF_BR_LOCAL_OUT) | (1 << NF_BR_BROUTING),
.target = ebt_dnat_tg,
.checkentry = ebt_dnat_tg_check,
.targetsize = XT_ALIGN(sizeof(struct ebt_nat_info)),
.me = THIS_MODULE,
};
static int __init ebt_dnat_init(void)
{
return xt_register_target(&ebt_dnat_tg_reg);
}
static void __exit ebt_dnat_fini(void)
{
xt_unregister_target(&ebt_dnat_tg_reg);
}
module_init(ebt_dnat_init);
module_exit(ebt_dnat_fini);
MODULE_DESCRIPTION("Ebtables: Destination MAC address translation");
MODULE_LICENSE("GPL");
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