Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * This is the 1999 rewrite of IP Firewalling, aiming for kernel 2.3.x. | |
3 | * | |
4 | * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling | |
5 | * Copyright (C) 2000-2004 Netfilter Core Team <coreteam@netfilter.org> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | */ | |
11 | ||
12 | #include <linux/module.h> | |
13 | #include <linux/moduleparam.h> | |
14 | #include <linux/netfilter_ipv6/ip6_tables.h> | |
15 | ||
16 | MODULE_LICENSE("GPL"); | |
17 | MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); | |
18 | MODULE_DESCRIPTION("ip6tables filter table"); | |
19 | ||
20 | #define FILTER_VALID_HOOKS ((1 << NF_IP6_LOCAL_IN) | (1 << NF_IP6_FORWARD) | (1 << NF_IP6_LOCAL_OUT)) | |
21 | ||
22 | /* Standard entry. */ | |
23 | struct ip6t_standard | |
24 | { | |
25 | struct ip6t_entry entry; | |
26 | struct ip6t_standard_target target; | |
27 | }; | |
28 | ||
29 | struct ip6t_error_target | |
30 | { | |
31 | struct ip6t_entry_target target; | |
32 | char errorname[IP6T_FUNCTION_MAXNAMELEN]; | |
33 | }; | |
34 | ||
35 | struct ip6t_error | |
36 | { | |
37 | struct ip6t_entry entry; | |
38 | struct ip6t_error_target target; | |
39 | }; | |
40 | ||
41 | static struct | |
42 | { | |
43 | struct ip6t_replace repl; | |
44 | struct ip6t_standard entries[3]; | |
45 | struct ip6t_error term; | |
46 | } initial_table __initdata | |
47 | = { { "filter", FILTER_VALID_HOOKS, 4, | |
48 | sizeof(struct ip6t_standard) * 3 + sizeof(struct ip6t_error), | |
49 | { [NF_IP6_LOCAL_IN] = 0, | |
50 | [NF_IP6_FORWARD] = sizeof(struct ip6t_standard), | |
51 | [NF_IP6_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2 }, | |
52 | { [NF_IP6_LOCAL_IN] = 0, | |
53 | [NF_IP6_FORWARD] = sizeof(struct ip6t_standard), | |
54 | [NF_IP6_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2 }, | |
55 | 0, NULL, { } }, | |
56 | { | |
57 | /* LOCAL_IN */ | |
58 | { { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 }, | |
59 | 0, | |
60 | sizeof(struct ip6t_entry), | |
61 | sizeof(struct ip6t_standard), | |
62 | 0, { 0, 0 }, { } }, | |
63 | { { { { IP6T_ALIGN(sizeof(struct ip6t_standard_target)), "" } }, { } }, | |
64 | -NF_ACCEPT - 1 } }, | |
65 | /* FORWARD */ | |
66 | { { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 }, | |
67 | 0, | |
68 | sizeof(struct ip6t_entry), | |
69 | sizeof(struct ip6t_standard), | |
70 | 0, { 0, 0 }, { } }, | |
71 | { { { { IP6T_ALIGN(sizeof(struct ip6t_standard_target)), "" } }, { } }, | |
72 | -NF_ACCEPT - 1 } }, | |
73 | /* LOCAL_OUT */ | |
74 | { { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 }, | |
75 | 0, | |
76 | sizeof(struct ip6t_entry), | |
77 | sizeof(struct ip6t_standard), | |
78 | 0, { 0, 0 }, { } }, | |
79 | { { { { IP6T_ALIGN(sizeof(struct ip6t_standard_target)), "" } }, { } }, | |
80 | -NF_ACCEPT - 1 } } | |
81 | }, | |
82 | /* ERROR */ | |
83 | { { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 }, | |
84 | 0, | |
85 | sizeof(struct ip6t_entry), | |
86 | sizeof(struct ip6t_error), | |
87 | 0, { 0, 0 }, { } }, | |
88 | { { { { IP6T_ALIGN(sizeof(struct ip6t_error_target)), IP6T_ERROR_TARGET } }, | |
89 | { } }, | |
90 | "ERROR" | |
91 | } | |
92 | } | |
93 | }; | |
94 | ||
95 | static struct ip6t_table packet_filter = { | |
96 | .name = "filter", | |
97 | .valid_hooks = FILTER_VALID_HOOKS, | |
98 | .lock = RW_LOCK_UNLOCKED, | |
99 | .me = THIS_MODULE, | |
100 | }; | |
101 | ||
102 | /* The work comes in here from netfilter.c. */ | |
103 | static unsigned int | |
104 | ip6t_hook(unsigned int hook, | |
105 | struct sk_buff **pskb, | |
106 | const struct net_device *in, | |
107 | const struct net_device *out, | |
108 | int (*okfn)(struct sk_buff *)) | |
109 | { | |
110 | return ip6t_do_table(pskb, hook, in, out, &packet_filter, NULL); | |
111 | } | |
112 | ||
113 | static unsigned int | |
114 | ip6t_local_out_hook(unsigned int hook, | |
115 | struct sk_buff **pskb, | |
116 | const struct net_device *in, | |
117 | const struct net_device *out, | |
118 | int (*okfn)(struct sk_buff *)) | |
119 | { | |
120 | #if 0 | |
121 | /* root is playing with raw sockets. */ | |
122 | if ((*pskb)->len < sizeof(struct iphdr) | |
123 | || (*pskb)->nh.iph->ihl * 4 < sizeof(struct iphdr)) { | |
124 | if (net_ratelimit()) | |
125 | printk("ip6t_hook: happy cracking.\n"); | |
126 | return NF_ACCEPT; | |
127 | } | |
128 | #endif | |
129 | ||
130 | return ip6t_do_table(pskb, hook, in, out, &packet_filter, NULL); | |
131 | } | |
132 | ||
133 | static struct nf_hook_ops ip6t_ops[] = { | |
134 | { | |
135 | .hook = ip6t_hook, | |
136 | .owner = THIS_MODULE, | |
137 | .pf = PF_INET6, | |
138 | .hooknum = NF_IP6_LOCAL_IN, | |
139 | .priority = NF_IP6_PRI_FILTER, | |
140 | }, | |
141 | { | |
142 | .hook = ip6t_hook, | |
143 | .owner = THIS_MODULE, | |
144 | .pf = PF_INET6, | |
145 | .hooknum = NF_IP6_FORWARD, | |
146 | .priority = NF_IP6_PRI_FILTER, | |
147 | }, | |
148 | { | |
149 | .hook = ip6t_local_out_hook, | |
150 | .owner = THIS_MODULE, | |
151 | .pf = PF_INET6, | |
152 | .hooknum = NF_IP6_LOCAL_OUT, | |
153 | .priority = NF_IP6_PRI_FILTER, | |
154 | }, | |
155 | }; | |
156 | ||
157 | /* Default to forward because I got too much mail already. */ | |
158 | static int forward = NF_ACCEPT; | |
159 | module_param(forward, bool, 0000); | |
160 | ||
161 | static int __init init(void) | |
162 | { | |
163 | int ret; | |
164 | ||
165 | if (forward < 0 || forward > NF_MAX_VERDICT) { | |
166 | printk("iptables forward must be 0 or 1\n"); | |
167 | return -EINVAL; | |
168 | } | |
169 | ||
170 | /* Entry 1 is the FORWARD hook */ | |
171 | initial_table.entries[1].target.verdict = -forward - 1; | |
172 | ||
173 | /* Register table */ | |
174 | ret = ip6t_register_table(&packet_filter, &initial_table.repl); | |
175 | if (ret < 0) | |
176 | return ret; | |
177 | ||
178 | /* Register hooks */ | |
179 | ret = nf_register_hook(&ip6t_ops[0]); | |
180 | if (ret < 0) | |
181 | goto cleanup_table; | |
182 | ||
183 | ret = nf_register_hook(&ip6t_ops[1]); | |
184 | if (ret < 0) | |
185 | goto cleanup_hook0; | |
186 | ||
187 | ret = nf_register_hook(&ip6t_ops[2]); | |
188 | if (ret < 0) | |
189 | goto cleanup_hook1; | |
190 | ||
191 | return ret; | |
192 | ||
193 | cleanup_hook1: | |
194 | nf_unregister_hook(&ip6t_ops[1]); | |
195 | cleanup_hook0: | |
196 | nf_unregister_hook(&ip6t_ops[0]); | |
197 | cleanup_table: | |
198 | ip6t_unregister_table(&packet_filter); | |
199 | ||
200 | return ret; | |
201 | } | |
202 | ||
203 | static void __exit fini(void) | |
204 | { | |
205 | unsigned int i; | |
206 | ||
207 | for (i = 0; i < sizeof(ip6t_ops)/sizeof(struct nf_hook_ops); i++) | |
208 | nf_unregister_hook(&ip6t_ops[i]); | |
209 | ||
210 | ip6t_unregister_table(&packet_filter); | |
211 | } | |
212 | ||
213 | module_init(init); | |
214 | module_exit(fini); |