1/*
2 * 'raw' table, which is the very first hooked in at PRE_ROUTING and LOCAL_OUT .
3 *
4 * Copyright (C) 2003 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
5 */
6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7#include <linux/module.h>
8#include <linux/netfilter_ipv4/ip_tables.h>
9#include <linux/slab.h>
10#include <net/ip.h>
11
12#define RAW_VALID_HOOKS ((1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_OUT))
13
14static int __net_init iptable_raw_table_init(struct net *net);
15
16static bool raw_before_defrag __read_mostly;
17MODULE_PARM_DESC(raw_before_defrag, "Enable raw table before defrag");
18module_param(raw_before_defrag, bool, 0000);
19
20static const struct xt_table packet_raw = {
21 .name = "raw",
22 .valid_hooks = RAW_VALID_HOOKS,
23 .me = THIS_MODULE,
24 .af = NFPROTO_IPV4,
25 .priority = NF_IP_PRI_RAW,
26 .table_init = iptable_raw_table_init,
27};
28
29static const struct xt_table packet_raw_before_defrag = {
30 .name = "raw",
31 .valid_hooks = RAW_VALID_HOOKS,
32 .me = THIS_MODULE,
33 .af = NFPROTO_IPV4,
34 .priority = NF_IP_PRI_RAW_BEFORE_DEFRAG,
35 .table_init = iptable_raw_table_init,
36};
37
38/* The work comes in here from netfilter.c. */
39static unsigned int
40iptable_raw_hook(void *priv, struct sk_buff *skb,
41 const struct nf_hook_state *state)
42{
43 return ipt_do_table(skb, state, state->net->ipv4.iptable_raw);
44}
45
46static struct nf_hook_ops *rawtable_ops __read_mostly;
47
48static int __net_init iptable_raw_table_init(struct net *net)
49{
50 struct ipt_replace *repl;
51 const struct xt_table *table = &packet_raw;
52 int ret;
53
54 if (raw_before_defrag)
55 table = &packet_raw_before_defrag;
56
57 if (net->ipv4.iptable_raw)
58 return 0;
59
60 repl = ipt_alloc_initial_table(table);
61 if (repl == NULL)
62 return -ENOMEM;
63 ret = ipt_register_table(net, table, repl, rawtable_ops,
64 &net->ipv4.iptable_raw);
65 kfree(repl);
66 return ret;
67}
68
69static void __net_exit iptable_raw_net_exit(struct net *net)
70{
71 if (!net->ipv4.iptable_raw)
72 return;
73 ipt_unregister_table(net, net->ipv4.iptable_raw, rawtable_ops);
74 net->ipv4.iptable_raw = NULL;
75}
76
77static struct pernet_operations iptable_raw_net_ops = {
78 .exit = iptable_raw_net_exit,
79};
80
81static int __init iptable_raw_init(void)
82{
83 int ret;
84 const struct xt_table *table = &packet_raw;
85
86 if (raw_before_defrag) {
87 table = &packet_raw_before_defrag;
88
89 pr_info("Enabling raw table before defrag\n");
90 }
91
92 rawtable_ops = xt_hook_ops_alloc(table, iptable_raw_hook);
93 if (IS_ERR(rawtable_ops))
94 return PTR_ERR(rawtable_ops);
95
96 ret = register_pernet_subsys(&iptable_raw_net_ops);
97 if (ret < 0) {
98 kfree(rawtable_ops);
99 return ret;
100 }
101
102 ret = iptable_raw_table_init(&init_net);
103 if (ret) {
104 unregister_pernet_subsys(&iptable_raw_net_ops);
105 kfree(rawtable_ops);
106 }
107
108 return ret;
109}
110
111static void __exit iptable_raw_fini(void)
112{
113 unregister_pernet_subsys(&iptable_raw_net_ops);
114 kfree(rawtable_ops);
115}
116
117module_init(iptable_raw_init);
118module_exit(iptable_raw_fini);
119MODULE_LICENSE("GPL");
120