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/*
* ebtable_broute
*
* Authors:
* Bart De Schuymer <bart.de.schuymer@pandora.be>
*
* April, 2002
*
* This table lets you choose between routing and bridging for frames
* entering on a bridge enslaved nic. This table is traversed before any
* other ebtables table. See net/bridge/br_input.c.
*/
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge.h>
#include <linux/netdevice.h>
#include <linux/module.h>
#include <linux/if_bridge.h>
#include <linux/brlock.h>
// EBT_ACCEPT means the frame will be bridged
// EBT_DROP means the frame will be routed
static struct ebt_entries initial_chain =
{0, "BROUTING", 0, EBT_ACCEPT, 0};
static struct ebt_replace initial_table =
{
"broute", 1 << NF_BR_BROUTING, 0, sizeof(struct ebt_entries),
{ [NF_BR_BROUTING]&initial_chain}, 0, NULL, (char *)&initial_chain
};
static int check(const struct ebt_table_info *info, unsigned int valid_hooks)
{
if (valid_hooks & ~(1 << NF_BR_BROUTING))
return -EINVAL;
return 0;
}
static struct ebt_table broute_table =
{
{NULL, NULL}, "broute", &initial_table, 1 << NF_BR_BROUTING,
RW_LOCK_UNLOCKED, check, NULL
};
static unsigned int
ebt_broute (unsigned int hook, struct sk_buff **pskb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
return ebt_do_table(hook, pskb, in, out, &broute_table);
}
static int __init init(void)
{
int ret;
ret = ebt_register_table(&broute_table);
if (ret < 0)
return ret;
br_write_lock_bh(BR_NETPROTO_LOCK);
// in br_input.c, br_handle_frame() wants to call broute_decision()
broute_decision = ebt_broute;
br_write_unlock_bh(BR_NETPROTO_LOCK);
return ret;
}
static void __exit fini(void)
{
br_write_lock_bh(BR_NETPROTO_LOCK);
broute_decision = NULL;
br_write_unlock_bh(BR_NETPROTO_LOCK);
ebt_unregister_table(&broute_table);
}
module_init(init);
module_exit(fini);
EXPORT_NO_SYMBOLS;
MODULE_LICENSE("GPL");
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