Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* Kernel module to match connection tracking information. */ |
2 | ||
3 | /* (C) 1999-2001 Paul `Rusty' Russell | |
2e4e6a17 | 4 | * (C) 2002-2005 Netfilter Core Team <coreteam@netfilter.org> |
1da177e4 LT |
5 | * |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | */ | |
10 | ||
11 | #include <linux/module.h> | |
12 | #include <linux/skbuff.h> | |
587aa641 | 13 | #include <net/netfilter/nf_conntrack.h> |
2e4e6a17 HW |
14 | #include <linux/netfilter/x_tables.h> |
15 | #include <linux/netfilter/xt_state.h> | |
1da177e4 LT |
16 | |
17 | MODULE_LICENSE("GPL"); | |
18 | MODULE_AUTHOR("Rusty Russell <rusty@rustcorp.com.au>"); | |
2e4e6a17 HW |
19 | MODULE_DESCRIPTION("ip[6]_tables connection tracking state match module"); |
20 | MODULE_ALIAS("ipt_state"); | |
21 | MODULE_ALIAS("ip6t_state"); | |
1da177e4 | 22 | |
1d93a9cb | 23 | static bool |
f7108a20 | 24 | state_mt(const struct sk_buff *skb, const struct xt_match_param *par) |
1da177e4 | 25 | { |
f7108a20 | 26 | const struct xt_state_info *sinfo = par->matchinfo; |
1da177e4 LT |
27 | enum ip_conntrack_info ctinfo; |
28 | unsigned int statebit; | |
29 | ||
9fb9cbb1 | 30 | if (nf_ct_is_untracked(skb)) |
2e4e6a17 | 31 | statebit = XT_STATE_UNTRACKED; |
587aa641 | 32 | else if (!nf_ct_get(skb, &ctinfo)) |
2e4e6a17 | 33 | statebit = XT_STATE_INVALID; |
1da177e4 | 34 | else |
2e4e6a17 | 35 | statebit = XT_STATE_BIT(ctinfo); |
1da177e4 LT |
36 | |
37 | return (sinfo->statemask & statebit); | |
38 | } | |
39 | ||
d3c5ee6d JE |
40 | static bool |
41 | state_mt_check(const char *tablename, const void *inf, | |
42 | const struct xt_match *match, void *matchinfo, | |
43 | unsigned int hook_mask) | |
b9f78f9f | 44 | { |
b9f78f9f | 45 | if (nf_ct_l3proto_try_module_get(match->family) < 0) { |
fe0b9294 | 46 | printk(KERN_WARNING "can't load conntrack support for " |
df54aae0 | 47 | "proto=%u\n", match->family); |
ccb79bdc | 48 | return false; |
b9f78f9f | 49 | } |
ccb79bdc | 50 | return true; |
b9f78f9f PNA |
51 | } |
52 | ||
d3c5ee6d | 53 | static void state_mt_destroy(const struct xt_match *match, void *matchinfo) |
b9f78f9f | 54 | { |
b9f78f9f | 55 | nf_ct_l3proto_module_put(match->family); |
b9f78f9f PNA |
56 | } |
57 | ||
d3c5ee6d | 58 | static struct xt_match state_mt_reg[] __read_mostly = { |
4470bbc7 PM |
59 | { |
60 | .name = "state", | |
ee999d8b | 61 | .family = NFPROTO_IPV4, |
d3c5ee6d JE |
62 | .checkentry = state_mt_check, |
63 | .match = state_mt, | |
64 | .destroy = state_mt_destroy, | |
4470bbc7 PM |
65 | .matchsize = sizeof(struct xt_state_info), |
66 | .me = THIS_MODULE, | |
67 | }, | |
68 | { | |
69 | .name = "state", | |
ee999d8b | 70 | .family = NFPROTO_IPV6, |
d3c5ee6d JE |
71 | .checkentry = state_mt_check, |
72 | .match = state_mt, | |
73 | .destroy = state_mt_destroy, | |
4470bbc7 PM |
74 | .matchsize = sizeof(struct xt_state_info), |
75 | .me = THIS_MODULE, | |
76 | }, | |
1da177e4 LT |
77 | }; |
78 | ||
d3c5ee6d | 79 | static int __init state_mt_init(void) |
1da177e4 | 80 | { |
d3c5ee6d | 81 | return xt_register_matches(state_mt_reg, ARRAY_SIZE(state_mt_reg)); |
1da177e4 LT |
82 | } |
83 | ||
d3c5ee6d | 84 | static void __exit state_mt_exit(void) |
1da177e4 | 85 | { |
d3c5ee6d | 86 | xt_unregister_matches(state_mt_reg, ARRAY_SIZE(state_mt_reg)); |
1da177e4 LT |
87 | } |
88 | ||
d3c5ee6d JE |
89 | module_init(state_mt_init); |
90 | module_exit(state_mt_exit); |