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14#include <linux/netfilter_bridge/ebtables.h>
15#include <linux/module.h>
16#include <linux/if_bridge.h>
17
18
19
20
21static struct ebt_entries initial_chain = {
22 .name = "BROUTING",
23 .policy = EBT_ACCEPT,
24};
25
26static struct ebt_replace_kernel initial_table =
27{
28 .name = "broute",
29 .valid_hooks = 1 << NF_BR_BROUTING,
30 .entries_size = sizeof(struct ebt_entries),
31 .hook_entry = {
32 [NF_BR_BROUTING] = &initial_chain,
33 },
34 .entries = (char *)&initial_chain,
35};
36
37static int check(const struct ebt_table_info *info, unsigned int valid_hooks)
38{
39 if (valid_hooks & ~(1 << NF_BR_BROUTING))
40 return -EINVAL;
41 return 0;
42}
43
44static const struct ebt_table broute_table =
45{
46 .name = "broute",
47 .table = &initial_table,
48 .valid_hooks = 1 << NF_BR_BROUTING,
49 .check = check,
50 .me = THIS_MODULE,
51};
52
53static int ebt_broute(struct sk_buff *skb)
54{
55 int ret;
56
57 ret = ebt_do_table(NF_BR_BROUTING, skb, skb->dev, NULL,
58 dev_net(skb->dev)->xt.broute_table);
59 if (ret == NF_DROP)
60 return 1;
61 return 0;
62}
63
64static int __net_init broute_net_init(struct net *net)
65{
66 net->xt.broute_table = ebt_register_table(net, &broute_table);
67 if (IS_ERR(net->xt.broute_table))
68 return PTR_ERR(net->xt.broute_table);
69 return 0;
70}
71
72static void __net_exit broute_net_exit(struct net *net)
73{
74 ebt_unregister_table(net, net->xt.broute_table);
75}
76
77static struct pernet_operations broute_net_ops = {
78 .init = broute_net_init,
79 .exit = broute_net_exit,
80};
81
82static int __init ebtable_broute_init(void)
83{
84 int ret;
85
86 ret = register_pernet_subsys(&broute_net_ops);
87 if (ret < 0)
88 return ret;
89
90 RCU_INIT_POINTER(br_should_route_hook,
91 (br_should_route_hook_t *)ebt_broute);
92 return 0;
93}
94
95static void __exit ebtable_broute_fini(void)
96{
97 RCU_INIT_POINTER(br_should_route_hook, NULL);
98 synchronize_net();
99 unregister_pernet_subsys(&broute_net_ops);
100}
101
102module_init(ebtable_broute_init);
103module_exit(ebtable_broute_fini);
104MODULE_LICENSE("GPL");
105