1// SPDX-License-Identifier: GPL-2.0
2
3#include <linux/module.h>
4#include <linux/netfilter/nf_tables.h>
5#include <net/netfilter/nf_nat.h>
6#include <net/netfilter/nf_tables.h>
7#include <net/netfilter/nf_tables_ipv4.h>
8#include <net/netfilter/nf_tables_ipv6.h>
9
10static unsigned int nft_nat_do_chain(void *priv, struct sk_buff *skb,
11 const struct nf_hook_state *state)
12{
13 struct nft_pktinfo pkt;
14
15 nft_set_pktinfo(pkt: &pkt, skb, state);
16
17 switch (state->pf) {
18#ifdef CONFIG_NF_TABLES_IPV4
19 case NFPROTO_IPV4:
20 nft_set_pktinfo_ipv4(pkt: &pkt);
21 break;
22#endif
23#ifdef CONFIG_NF_TABLES_IPV6
24 case NFPROTO_IPV6:
25 nft_set_pktinfo_ipv6(pkt: &pkt);
26 break;
27#endif
28 default:
29 break;
30 }
31
32 return nft_do_chain(pkt: &pkt, priv);
33}
34
35#ifdef CONFIG_NF_TABLES_IPV4
36static const struct nft_chain_type nft_chain_nat_ipv4 = {
37 .name = "nat",
38 .type = NFT_CHAIN_T_NAT,
39 .family = NFPROTO_IPV4,
40 .owner = THIS_MODULE,
41 .hook_mask = (1 << NF_INET_PRE_ROUTING) |
42 (1 << NF_INET_POST_ROUTING) |
43 (1 << NF_INET_LOCAL_OUT) |
44 (1 << NF_INET_LOCAL_IN),
45 .hooks = {
46 [NF_INET_PRE_ROUTING] = nft_nat_do_chain,
47 [NF_INET_POST_ROUTING] = nft_nat_do_chain,
48 [NF_INET_LOCAL_OUT] = nft_nat_do_chain,
49 [NF_INET_LOCAL_IN] = nft_nat_do_chain,
50 },
51 .ops_register = nf_nat_ipv4_register_fn,
52 .ops_unregister = nf_nat_ipv4_unregister_fn,
53};
54#endif
55
56#ifdef CONFIG_NF_TABLES_IPV6
57static const struct nft_chain_type nft_chain_nat_ipv6 = {
58 .name = "nat",
59 .type = NFT_CHAIN_T_NAT,
60 .family = NFPROTO_IPV6,
61 .owner = THIS_MODULE,
62 .hook_mask = (1 << NF_INET_PRE_ROUTING) |
63 (1 << NF_INET_POST_ROUTING) |
64 (1 << NF_INET_LOCAL_OUT) |
65 (1 << NF_INET_LOCAL_IN),
66 .hooks = {
67 [NF_INET_PRE_ROUTING] = nft_nat_do_chain,
68 [NF_INET_POST_ROUTING] = nft_nat_do_chain,
69 [NF_INET_LOCAL_OUT] = nft_nat_do_chain,
70 [NF_INET_LOCAL_IN] = nft_nat_do_chain,
71 },
72 .ops_register = nf_nat_ipv6_register_fn,
73 .ops_unregister = nf_nat_ipv6_unregister_fn,
74};
75#endif
76
77#ifdef CONFIG_NF_TABLES_INET
78static int nft_nat_inet_reg(struct net *net, const struct nf_hook_ops *ops)
79{
80 return nf_nat_inet_register_fn(net, ops);
81}
82
83static void nft_nat_inet_unreg(struct net *net, const struct nf_hook_ops *ops)
84{
85 nf_nat_inet_unregister_fn(net, ops);
86}
87
88static const struct nft_chain_type nft_chain_nat_inet = {
89 .name = "nat",
90 .type = NFT_CHAIN_T_NAT,
91 .family = NFPROTO_INET,
92 .owner = THIS_MODULE,
93 .hook_mask = (1 << NF_INET_PRE_ROUTING) |
94 (1 << NF_INET_LOCAL_IN) |
95 (1 << NF_INET_LOCAL_OUT) |
96 (1 << NF_INET_POST_ROUTING),
97 .hooks = {
98 [NF_INET_PRE_ROUTING] = nft_nat_do_chain,
99 [NF_INET_LOCAL_IN] = nft_nat_do_chain,
100 [NF_INET_LOCAL_OUT] = nft_nat_do_chain,
101 [NF_INET_POST_ROUTING] = nft_nat_do_chain,
102 },
103 .ops_register = nft_nat_inet_reg,
104 .ops_unregister = nft_nat_inet_unreg,
105};
106#endif
107
108static int __init nft_chain_nat_init(void)
109{
110#ifdef CONFIG_NF_TABLES_IPV6
111 nft_register_chain_type(&nft_chain_nat_ipv6);
112#endif
113#ifdef CONFIG_NF_TABLES_IPV4
114 nft_register_chain_type(&nft_chain_nat_ipv4);
115#endif
116#ifdef CONFIG_NF_TABLES_INET
117 nft_register_chain_type(&nft_chain_nat_inet);
118#endif
119
120 return 0;
121}
122
123static void __exit nft_chain_nat_exit(void)
124{
125#ifdef CONFIG_NF_TABLES_IPV4
126 nft_unregister_chain_type(&nft_chain_nat_ipv4);
127#endif
128#ifdef CONFIG_NF_TABLES_IPV6
129 nft_unregister_chain_type(&nft_chain_nat_ipv6);
130#endif
131#ifdef CONFIG_NF_TABLES_INET
132 nft_unregister_chain_type(&nft_chain_nat_inet);
133#endif
134}
135
136module_init(nft_chain_nat_init);
137module_exit(nft_chain_nat_exit);
138
139MODULE_LICENSE("GPL");
140MODULE_DESCRIPTION("nftables network address translation support");
141#ifdef CONFIG_NF_TABLES_IPV4
142MODULE_ALIAS_NFT_CHAIN(AF_INET, "nat");
143#endif
144#ifdef CONFIG_NF_TABLES_IPV6
145MODULE_ALIAS_NFT_CHAIN(AF_INET6, "nat");
146#endif
147#ifdef CONFIG_NF_TABLES_INET
148MODULE_ALIAS_NFT_CHAIN(1, "nat"); /* NFPROTO_INET */
149#endif
150

source code of linux/net/netfilter/nft_chain_nat.c