1/*
2 *  ebtable_broute
3 *
4 *	Authors:
5 *	Bart De Schuymer <bdschuym@pandora.be>
6 *
7 *  April, 2002
8 *
9 *  This table lets you choose between routing and bridging for frames
10 *  entering on a bridge enslaved nic. This table is traversed before any
11 *  other ebtables table. See net/bridge/br_input.c.
12 */
13
14#include <linux/netfilter_bridge/ebtables.h>
15#include <linux/module.h>
16#include <linux/if_bridge.h>
17
18/* EBT_ACCEPT means the frame will be bridged
19 * EBT_DROP means the frame will be routed
20 */
21static struct ebt_entries initial_chain = {
22	.name		= "BROUTING",
23	.policy		= EBT_ACCEPT,
24};
25
26static struct ebt_replace_kernel initial_table = {
27	.name		= "broute",
28	.valid_hooks	= 1 << NF_BR_BROUTING,
29	.entries_size	= sizeof(struct ebt_entries),
30	.hook_entry	= {
31		[NF_BR_BROUTING]	= &initial_chain,
32	},
33	.entries	= (char *)&initial_chain,
34};
35
36static int check(const struct ebt_table_info *info, unsigned int valid_hooks)
37{
38	if (valid_hooks & ~(1 << NF_BR_BROUTING))
39		return -EINVAL;
40	return 0;
41}
42
43static const struct ebt_table broute_table = {
44	.name		= "broute",
45	.table		= &initial_table,
46	.valid_hooks	= 1 << NF_BR_BROUTING,
47	.check		= check,
48	.me		= THIS_MODULE,
49};
50
51static int ebt_broute(struct sk_buff *skb)
52{
53	int ret;
54
55	ret = ebt_do_table(NF_BR_BROUTING, skb, skb->dev, NULL,
56			   dev_net(skb->dev)->xt.broute_table);
57	if (ret == NF_DROP)
58		return 1; /* route it */
59	return 0; /* bridge it */
60}
61
62static int __net_init broute_net_init(struct net *net)
63{
64	net->xt.broute_table = ebt_register_table(net, &broute_table);
65	return PTR_ERR_OR_ZERO(net->xt.broute_table);
66}
67
68static void __net_exit broute_net_exit(struct net *net)
69{
70	ebt_unregister_table(net, net->xt.broute_table);
71}
72
73static struct pernet_operations broute_net_ops = {
74	.init = broute_net_init,
75	.exit = broute_net_exit,
76};
77
78static int __init ebtable_broute_init(void)
79{
80	int ret;
81
82	ret = register_pernet_subsys(&broute_net_ops);
83	if (ret < 0)
84		return ret;
85	/* see br_input.c */
86	RCU_INIT_POINTER(br_should_route_hook,
87			   (br_should_route_hook_t *)ebt_broute);
88	return 0;
89}
90
91static void __exit ebtable_broute_fini(void)
92{
93	RCU_INIT_POINTER(br_should_route_hook, NULL);
94	synchronize_net();
95	unregister_pernet_subsys(&broute_net_ops);
96}
97
98module_init(ebtable_broute_init);
99module_exit(ebtable_broute_fini);
100MODULE_LICENSE("GPL");
101