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12#include <linux/module.h>
13#include <linux/moduleparam.h>
14#include <linux/netfilter_ipv6/ip6_tables.h>
15
16MODULE_LICENSE("GPL");
17MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
18MODULE_DESCRIPTION("ip6tables filter table");
19
20#define FILTER_VALID_HOOKS ((1 << NF_INET_LOCAL_IN) | \
21 (1 << NF_INET_FORWARD) | \
22 (1 << NF_INET_LOCAL_OUT))
23
24static struct
25{
26 struct ip6t_replace repl;
27 struct ip6t_standard entries[3];
28 struct ip6t_error term;
29} initial_table __net_initdata = {
30 .repl = {
31 .name = "filter",
32 .valid_hooks = FILTER_VALID_HOOKS,
33 .num_entries = 4,
34 .size = sizeof(struct ip6t_standard) * 3 + sizeof(struct ip6t_error),
35 .hook_entry = {
36 [NF_INET_LOCAL_IN] = 0,
37 [NF_INET_FORWARD] = sizeof(struct ip6t_standard),
38 [NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2
39 },
40 .underflow = {
41 [NF_INET_LOCAL_IN] = 0,
42 [NF_INET_FORWARD] = sizeof(struct ip6t_standard),
43 [NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2
44 },
45 },
46 .entries = {
47 IP6T_STANDARD_INIT(NF_ACCEPT),
48 IP6T_STANDARD_INIT(NF_ACCEPT),
49 IP6T_STANDARD_INIT(NF_ACCEPT),
50 },
51 .term = IP6T_ERROR_INIT,
52};
53
54static const struct xt_table packet_filter = {
55 .name = "filter",
56 .valid_hooks = FILTER_VALID_HOOKS,
57 .me = THIS_MODULE,
58 .af = NFPROTO_IPV6,
59};
60
61
62static unsigned int
63ip6t_in_hook(unsigned int hook,
64 struct sk_buff *skb,
65 const struct net_device *in,
66 const struct net_device *out,
67 int (*okfn)(struct sk_buff *))
68{
69 return ip6t_do_table(skb, hook, in, out,
70 dev_net(in)->ipv6.ip6table_filter);
71}
72
73static unsigned int
74ip6t_local_out_hook(unsigned int hook,
75 struct sk_buff *skb,
76 const struct net_device *in,
77 const struct net_device *out,
78 int (*okfn)(struct sk_buff *))
79{
80#if 0
81
82 if (skb->len < sizeof(struct iphdr)
83 || ip_hdrlen(skb) < sizeof(struct iphdr)) {
84 if (net_ratelimit())
85 printk("ip6t_hook: happy cracking.\n");
86 return NF_ACCEPT;
87 }
88#endif
89
90 return ip6t_do_table(skb, hook, in, out,
91 dev_net(out)->ipv6.ip6table_filter);
92}
93
94static struct nf_hook_ops ip6t_ops[] __read_mostly = {
95 {
96 .hook = ip6t_in_hook,
97 .owner = THIS_MODULE,
98 .pf = NFPROTO_IPV6,
99 .hooknum = NF_INET_LOCAL_IN,
100 .priority = NF_IP6_PRI_FILTER,
101 },
102 {
103 .hook = ip6t_in_hook,
104 .owner = THIS_MODULE,
105 .pf = NFPROTO_IPV6,
106 .hooknum = NF_INET_FORWARD,
107 .priority = NF_IP6_PRI_FILTER,
108 },
109 {
110 .hook = ip6t_local_out_hook,
111 .owner = THIS_MODULE,
112 .pf = NFPROTO_IPV6,
113 .hooknum = NF_INET_LOCAL_OUT,
114 .priority = NF_IP6_PRI_FILTER,
115 },
116};
117
118
119static int forward = NF_ACCEPT;
120module_param(forward, bool, 0000);
121
122static int __net_init ip6table_filter_net_init(struct net *net)
123{
124
125 net->ipv6.ip6table_filter =
126 ip6t_register_table(net, &packet_filter, &initial_table.repl);
127 if (IS_ERR(net->ipv6.ip6table_filter))
128 return PTR_ERR(net->ipv6.ip6table_filter);
129 return 0;
130}
131
132static void __net_exit ip6table_filter_net_exit(struct net *net)
133{
134 ip6t_unregister_table(net->ipv6.ip6table_filter);
135}
136
137static struct pernet_operations ip6table_filter_net_ops = {
138 .init = ip6table_filter_net_init,
139 .exit = ip6table_filter_net_exit,
140};
141
142static int __init ip6table_filter_init(void)
143{
144 int ret;
145
146 if (forward < 0 || forward > NF_MAX_VERDICT) {
147 printk("iptables forward must be 0 or 1\n");
148 return -EINVAL;
149 }
150
151
152 initial_table.entries[1].target.verdict = -forward - 1;
153
154 ret = register_pernet_subsys(&ip6table_filter_net_ops);
155 if (ret < 0)
156 return ret;
157
158
159 ret = nf_register_hooks(ip6t_ops, ARRAY_SIZE(ip6t_ops));
160 if (ret < 0)
161 goto cleanup_table;
162
163 return ret;
164
165 cleanup_table:
166 unregister_pernet_subsys(&ip6table_filter_net_ops);
167 return ret;
168}
169
170static void __exit ip6table_filter_fini(void)
171{
172 nf_unregister_hooks(ip6t_ops, ARRAY_SIZE(ip6t_ops));
173 unregister_pernet_subsys(&ip6table_filter_net_ops);
174}
175
176module_init(ip6table_filter_init);
177module_exit(ip6table_filter_fini);
178