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/*
* ebt_redirect
*
* Authors:
* Bart De Schuymer <bdschuym@pandora.be>
*
* April, 2002
*
*/
#include <linux/module.h>
#include <net/sock.h>
#include "../br_private.h"
#include <linux/netfilter.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_redirect.h>
static unsigned int
ebt_redirect_tg(struct sk_buff *skb, const struct net_device *in,
const struct net_device *out, unsigned int hooknr,
const struct xt_target *target, const void *data)
{
const struct ebt_redirect_info *info = data;
if (!skb_make_writable(skb, 0))
return EBT_DROP;
if (hooknr != NF_BR_BROUTING)
memcpy(eth_hdr(skb)->h_dest,
in->br_port->br->dev->dev_addr, ETH_ALEN);
else
memcpy(eth_hdr(skb)->h_dest, in->dev_addr, ETH_ALEN);
skb->pkt_type = PACKET_HOST;
return info->target;
}
static bool
ebt_redirect_tg_check(const char *tablename, const void *e,
const struct xt_target *target, void *data,
unsigned int hookmask)
{
const struct ebt_redirect_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)) &&
(strcmp(tablename, "broute") || hookmask & ~(1 << NF_BR_BROUTING)) )
return false;
if (INVALID_TARGET)
return false;
return true;
}
static struct ebt_target redirect_target __read_mostly = {
.name = EBT_REDIRECT_TARGET,
.revision = 0,
.family = NFPROTO_BRIDGE,
.target = ebt_redirect_tg,
.checkentry = ebt_redirect_tg_check,
.targetsize = XT_ALIGN(sizeof(struct ebt_redirect_info)),
.me = THIS_MODULE,
};
static int __init ebt_redirect_init(void)
{
return ebt_register_target(&redirect_target);
}
static void __exit ebt_redirect_fini(void)
{
ebt_unregister_target(&redirect_target);
}
module_init(ebt_redirect_init);
module_exit(ebt_redirect_fini);
MODULE_DESCRIPTION("Ebtables: Packet redirection to localhost");
MODULE_LICENSE("GPL");
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