1 /* (C) 1999-2001 Paul `Rusty' Russell
2 * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
3 * (C) 2011 Patrick McHardy <kaber@trash.net>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 #include <linux/module.h>
11 #include <linux/netfilter.h>
12 #include <linux/netfilter_ipv4.h>
13 #include <linux/netfilter_ipv4/ip_tables.h>
17 #include <net/netfilter/nf_nat.h>
18 #include <net/netfilter/nf_nat_core.h>
19 #include <net/netfilter/nf_nat_l3proto.h>
21 static const struct xt_table nf_nat_ipv4_table = {
23 .valid_hooks = (1 << NF_INET_PRE_ROUTING) |
24 (1 << NF_INET_POST_ROUTING) |
25 (1 << NF_INET_LOCAL_OUT) |
26 (1 << NF_INET_LOCAL_IN),
31 static unsigned int iptable_nat_do_chain(void *priv,
33 const struct nf_hook_state *state,
36 return ipt_do_table(skb, state, state->net->ipv4.nat_table);
39 static unsigned int iptable_nat_ipv4_fn(void *priv,
41 const struct nf_hook_state *state)
43 return nf_nat_ipv4_fn(priv, skb, state, iptable_nat_do_chain);
46 static unsigned int iptable_nat_ipv4_in(void *priv,
48 const struct nf_hook_state *state)
50 return nf_nat_ipv4_in(priv, skb, state, iptable_nat_do_chain);
53 static unsigned int iptable_nat_ipv4_out(void *priv,
55 const struct nf_hook_state *state)
57 return nf_nat_ipv4_out(priv, skb, state, iptable_nat_do_chain);
60 static unsigned int iptable_nat_ipv4_local_fn(void *priv,
62 const struct nf_hook_state *state)
64 return nf_nat_ipv4_local_fn(priv, skb, state, iptable_nat_do_chain);
67 static struct nf_hook_ops nf_nat_ipv4_ops[] __read_mostly = {
68 /* Before packet filtering, change destination */
70 .hook = iptable_nat_ipv4_in,
72 .hooknum = NF_INET_PRE_ROUTING,
73 .priority = NF_IP_PRI_NAT_DST,
75 /* After packet filtering, change source */
77 .hook = iptable_nat_ipv4_out,
79 .hooknum = NF_INET_POST_ROUTING,
80 .priority = NF_IP_PRI_NAT_SRC,
82 /* Before packet filtering, change destination */
84 .hook = iptable_nat_ipv4_local_fn,
86 .hooknum = NF_INET_LOCAL_OUT,
87 .priority = NF_IP_PRI_NAT_DST,
89 /* After packet filtering, change source */
91 .hook = iptable_nat_ipv4_fn,
93 .hooknum = NF_INET_LOCAL_IN,
94 .priority = NF_IP_PRI_NAT_SRC,
98 static int __net_init iptable_nat_net_init(struct net *net)
100 struct ipt_replace *repl;
102 repl = ipt_alloc_initial_table(&nf_nat_ipv4_table);
105 net->ipv4.nat_table = ipt_register_table(net, &nf_nat_ipv4_table, repl);
107 return PTR_ERR_OR_ZERO(net->ipv4.nat_table);
110 static void __net_exit iptable_nat_net_exit(struct net *net)
112 ipt_unregister_table(net, net->ipv4.nat_table);
115 static struct pernet_operations iptable_nat_net_ops = {
116 .init = iptable_nat_net_init,
117 .exit = iptable_nat_net_exit,
120 static int __init iptable_nat_init(void)
124 err = register_pernet_subsys(&iptable_nat_net_ops);
128 err = nf_register_hooks(nf_nat_ipv4_ops, ARRAY_SIZE(nf_nat_ipv4_ops));
134 unregister_pernet_subsys(&iptable_nat_net_ops);
139 static void __exit iptable_nat_exit(void)
141 nf_unregister_hooks(nf_nat_ipv4_ops, ARRAY_SIZE(nf_nat_ipv4_ops));
142 unregister_pernet_subsys(&iptable_nat_net_ops);
145 module_init(iptable_nat_init);
146 module_exit(iptable_nat_exit);
148 MODULE_LICENSE("GPL");