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 int __net_init
iptable_nat_table_init(struct net
*net
);
23 static const struct xt_table nf_nat_ipv4_table
= {
25 .valid_hooks
= (1 << NF_INET_PRE_ROUTING
) |
26 (1 << NF_INET_POST_ROUTING
) |
27 (1 << NF_INET_LOCAL_OUT
) |
28 (1 << NF_INET_LOCAL_IN
),
31 .table_init
= iptable_nat_table_init
,
34 static unsigned int iptable_nat_do_chain(void *priv
,
36 const struct nf_hook_state
*state
,
39 return ipt_do_table(skb
, state
, state
->net
->ipv4
.nat_table
);
42 static unsigned int iptable_nat_ipv4_fn(void *priv
,
44 const struct nf_hook_state
*state
)
46 return nf_nat_ipv4_fn(priv
, skb
, state
, iptable_nat_do_chain
);
49 static unsigned int iptable_nat_ipv4_in(void *priv
,
51 const struct nf_hook_state
*state
)
53 return nf_nat_ipv4_in(priv
, skb
, state
, iptable_nat_do_chain
);
56 static unsigned int iptable_nat_ipv4_out(void *priv
,
58 const struct nf_hook_state
*state
)
60 return nf_nat_ipv4_out(priv
, skb
, state
, iptable_nat_do_chain
);
63 static unsigned int iptable_nat_ipv4_local_fn(void *priv
,
65 const struct nf_hook_state
*state
)
67 return nf_nat_ipv4_local_fn(priv
, skb
, state
, iptable_nat_do_chain
);
70 static const struct nf_hook_ops nf_nat_ipv4_ops
[] = {
71 /* Before packet filtering, change destination */
73 .hook
= iptable_nat_ipv4_in
,
75 .hooknum
= NF_INET_PRE_ROUTING
,
76 .priority
= NF_IP_PRI_NAT_DST
,
78 /* After packet filtering, change source */
80 .hook
= iptable_nat_ipv4_out
,
82 .hooknum
= NF_INET_POST_ROUTING
,
83 .priority
= NF_IP_PRI_NAT_SRC
,
85 /* Before packet filtering, change destination */
87 .hook
= iptable_nat_ipv4_local_fn
,
89 .hooknum
= NF_INET_LOCAL_OUT
,
90 .priority
= NF_IP_PRI_NAT_DST
,
92 /* After packet filtering, change source */
94 .hook
= iptable_nat_ipv4_fn
,
96 .hooknum
= NF_INET_LOCAL_IN
,
97 .priority
= NF_IP_PRI_NAT_SRC
,
101 static int __net_init
iptable_nat_table_init(struct net
*net
)
103 struct ipt_replace
*repl
;
106 if (net
->ipv4
.nat_table
)
109 repl
= ipt_alloc_initial_table(&nf_nat_ipv4_table
);
112 ret
= ipt_register_table(net
, &nf_nat_ipv4_table
, repl
,
113 nf_nat_ipv4_ops
, &net
->ipv4
.nat_table
);
118 static void __net_exit
iptable_nat_net_exit(struct net
*net
)
120 if (!net
->ipv4
.nat_table
)
122 ipt_unregister_table(net
, net
->ipv4
.nat_table
, nf_nat_ipv4_ops
);
123 net
->ipv4
.nat_table
= NULL
;
126 static struct pernet_operations iptable_nat_net_ops
= {
127 .exit
= iptable_nat_net_exit
,
130 static int __init
iptable_nat_init(void)
132 int ret
= register_pernet_subsys(&iptable_nat_net_ops
);
137 ret
= iptable_nat_table_init(&init_net
);
139 unregister_pernet_subsys(&iptable_nat_net_ops
);
143 static void __exit
iptable_nat_exit(void)
145 unregister_pernet_subsys(&iptable_nat_net_ops
);
148 module_init(iptable_nat_init
);
149 module_exit(iptable_nat_exit
);
151 MODULE_LICENSE("GPL");