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(const struct nf_hook_ops
*ops
,
33 const struct nf_hook_state
*state
,
36 return ipt_do_table(skb
, ops
->hooknum
, state
,
37 state
->net
->ipv4
.nat_table
);
40 static unsigned int iptable_nat_ipv4_fn(const struct nf_hook_ops
*ops
,
42 const struct nf_hook_state
*state
)
44 return nf_nat_ipv4_fn(ops
, skb
, state
, iptable_nat_do_chain
);
47 static unsigned int iptable_nat_ipv4_in(const struct nf_hook_ops
*ops
,
49 const struct nf_hook_state
*state
)
51 return nf_nat_ipv4_in(ops
, skb
, state
, iptable_nat_do_chain
);
54 static unsigned int iptable_nat_ipv4_out(const struct nf_hook_ops
*ops
,
56 const struct nf_hook_state
*state
)
58 return nf_nat_ipv4_out(ops
, skb
, state
, iptable_nat_do_chain
);
61 static unsigned int iptable_nat_ipv4_local_fn(const struct nf_hook_ops
*ops
,
63 const struct nf_hook_state
*state
)
65 return nf_nat_ipv4_local_fn(ops
, skb
, state
, iptable_nat_do_chain
);
68 static struct nf_hook_ops nf_nat_ipv4_ops
[] __read_mostly
= {
69 /* Before packet filtering, change destination */
71 .hook
= iptable_nat_ipv4_in
,
74 .hooknum
= NF_INET_PRE_ROUTING
,
75 .priority
= NF_IP_PRI_NAT_DST
,
77 /* After packet filtering, change source */
79 .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
,
90 .hooknum
= NF_INET_LOCAL_OUT
,
91 .priority
= NF_IP_PRI_NAT_DST
,
93 /* After packet filtering, change source */
95 .hook
= iptable_nat_ipv4_fn
,
98 .hooknum
= NF_INET_LOCAL_IN
,
99 .priority
= NF_IP_PRI_NAT_SRC
,
103 static int __net_init
iptable_nat_net_init(struct net
*net
)
105 struct ipt_replace
*repl
;
107 repl
= ipt_alloc_initial_table(&nf_nat_ipv4_table
);
110 net
->ipv4
.nat_table
= ipt_register_table(net
, &nf_nat_ipv4_table
, repl
);
112 return PTR_ERR_OR_ZERO(net
->ipv4
.nat_table
);
115 static void __net_exit
iptable_nat_net_exit(struct net
*net
)
117 ipt_unregister_table(net
, net
->ipv4
.nat_table
);
120 static struct pernet_operations iptable_nat_net_ops
= {
121 .init
= iptable_nat_net_init
,
122 .exit
= iptable_nat_net_exit
,
125 static int __init
iptable_nat_init(void)
129 err
= register_pernet_subsys(&iptable_nat_net_ops
);
133 err
= nf_register_hooks(nf_nat_ipv4_ops
, ARRAY_SIZE(nf_nat_ipv4_ops
));
139 unregister_pernet_subsys(&iptable_nat_net_ops
);
144 static void __exit
iptable_nat_exit(void)
146 nf_unregister_hooks(nf_nat_ipv4_ops
, ARRAY_SIZE(nf_nat_ipv4_ops
));
147 unregister_pernet_subsys(&iptable_nat_net_ops
);
150 module_init(iptable_nat_init
);
151 module_exit(iptable_nat_exit
);
153 MODULE_LICENSE("GPL");