Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc
[cris-mirror.git] / net / netfilter / xt_state.c
bloba507922d80cdc2854a141acde78e5410bf918a48
1 /* Kernel module to match connection tracking information. */
3 /* (C) 1999-2001 Paul `Rusty' Russell
4 * (C) 2002-2005 Netfilter Core Team <coreteam@netfilter.org>
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 */
11 #include <linux/module.h>
12 #include <linux/skbuff.h>
13 #include <net/netfilter/nf_conntrack.h>
14 #include <linux/netfilter/x_tables.h>
15 #include <linux/netfilter/xt_state.h>
17 MODULE_LICENSE("GPL");
18 MODULE_AUTHOR("Rusty Russell <rusty@rustcorp.com.au>");
19 MODULE_DESCRIPTION("ip[6]_tables connection tracking state match module");
20 MODULE_ALIAS("ipt_state");
21 MODULE_ALIAS("ip6t_state");
23 static bool
24 state_mt(const struct sk_buff *skb, struct xt_action_param *par)
26 const struct xt_state_info *sinfo = par->matchinfo;
27 enum ip_conntrack_info ctinfo;
28 unsigned int statebit;
29 struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
31 if (!ct)
32 statebit = XT_STATE_INVALID;
33 else {
34 if (nf_ct_is_untracked(ct))
35 statebit = XT_STATE_UNTRACKED;
36 else
37 statebit = XT_STATE_BIT(ctinfo);
39 return (sinfo->statemask & statebit);
42 static int state_mt_check(const struct xt_mtchk_param *par)
44 int ret;
46 ret = nf_ct_l3proto_try_module_get(par->family);
47 if (ret < 0)
48 pr_info("cannot load conntrack support for proto=%u\n",
49 par->family);
50 return ret;
53 static void state_mt_destroy(const struct xt_mtdtor_param *par)
55 nf_ct_l3proto_module_put(par->family);
58 static struct xt_match state_mt_reg __read_mostly = {
59 .name = "state",
60 .family = NFPROTO_UNSPEC,
61 .checkentry = state_mt_check,
62 .match = state_mt,
63 .destroy = state_mt_destroy,
64 .matchsize = sizeof(struct xt_state_info),
65 .me = THIS_MODULE,
68 static int __init state_mt_init(void)
70 return xt_register_match(&state_mt_reg);
73 static void __exit state_mt_exit(void)
75 xt_unregister_match(&state_mt_reg);
78 module_init(state_mt_init);
79 module_exit(state_mt_exit);