- 根目录:
- net
- bridge
- netfilter
- ebt_dnat.c
/*
* 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 xt_action_param *par)
{
const struct ebt_nat_info *info = par->targinfo;
if (!skb_make_writable(skb, 0))
return EBT_DROP;
memcpy(eth_hdr(skb)->h_dest, info->mac, ETH_ALEN);
return info->target;
}
static int ebt_dnat_tg_check(const struct xt_tgchk_param *par)
{
const struct ebt_nat_info *info = par->targinfo;
unsigned int hook_mask;
if (BASE_CHAIN && info->target == EBT_RETURN)
return -EINVAL;
hook_mask = par->hook_mask & ~(1 << NF_BR_NUMHOOKS);
if ((strcmp(par->table, "nat") != 0 ||
(hook_mask & ~((1 << NF_BR_PRE_ROUTING) |
(1 << NF_BR_LOCAL_OUT)))) &&
(strcmp(par->table, "broute") != 0 ||
hook_mask & ~(1 << NF_BR_BROUTING)))
return -EINVAL;
if (INVALID_TARGET)
return -EINVAL;
return 0;
}
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 = 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");