1 // SPDX-License-Identifier: GPL-2.0-only
6 * Bart De Schuymer <bdschuym@pandora.be>
12 #include <linux/netfilter_bridge/ebtables.h>
13 #include <uapi/linux/netfilter_bridge.h>
14 #include <linux/module.h>
16 #define NAT_VALID_HOOKS ((1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_LOCAL_OUT) | \
17 (1 << NF_BR_POST_ROUTING))
19 static struct ebt_entries initial_chains[] = {
29 .name = "POSTROUTING",
34 static struct ebt_replace_kernel initial_table = {
36 .valid_hooks = NAT_VALID_HOOKS,
37 .entries_size = 3 * sizeof(struct ebt_entries),
39 [NF_BR_PRE_ROUTING] = &initial_chains[0],
40 [NF_BR_LOCAL_OUT] = &initial_chains[1],
41 [NF_BR_POST_ROUTING] = &initial_chains[2],
43 .entries = (char *)initial_chains,
46 static int check(const struct ebt_table_info *info, unsigned int valid_hooks)
48 if (valid_hooks & ~NAT_VALID_HOOKS)
53 static const struct ebt_table frame_nat = {
55 .table = &initial_table,
56 .valid_hooks = NAT_VALID_HOOKS,
61 static const struct nf_hook_ops ebt_ops_nat[] = {
65 .hooknum = NF_BR_LOCAL_OUT,
66 .priority = NF_BR_PRI_NAT_DST_OTHER,
71 .hooknum = NF_BR_POST_ROUTING,
72 .priority = NF_BR_PRI_NAT_SRC,
77 .hooknum = NF_BR_PRE_ROUTING,
78 .priority = NF_BR_PRI_NAT_DST_BRIDGED,
82 static int frame_nat_table_init(struct net *net)
84 return ebt_register_table(net, &frame_nat, ebt_ops_nat);
87 static void __net_exit frame_nat_net_pre_exit(struct net *net)
89 ebt_unregister_table_pre_exit(net, "nat");
92 static void __net_exit frame_nat_net_exit(struct net *net)
94 ebt_unregister_table(net, "nat");
97 static struct pernet_operations frame_nat_net_ops = {
98 .exit = frame_nat_net_exit,
99 .pre_exit = frame_nat_net_pre_exit,
102 static int __init ebtable_nat_init(void)
104 int ret = ebt_register_template(&frame_nat, frame_nat_table_init);
109 ret = register_pernet_subsys(&frame_nat_net_ops);
111 ebt_unregister_template(&frame_nat);
118 static void __exit ebtable_nat_fini(void)
120 unregister_pernet_subsys(&frame_nat_net_ops);
121 ebt_unregister_template(&frame_nat);
124 module_init(ebtable_nat_init);
125 module_exit(ebtable_nat_fini);
126 MODULE_LICENSE("GPL");