[linux-2.6-block.git] / net / netfilter / xt_CT.c

/*
 * Copyright (c) 2010 Patrick McHardy <kaber@trash.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/skbuff.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_CT.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_l4proto.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_ecache.h>
#include <net/netfilter/nf_conntrack_timeout.h>
#include <net/netfilter/nf_conntrack_zones.h>

static inline int xt_ct_target(struct sk_buff *skb, struct nf_conn *ct)
{
	/* Previously seen (loopback)? Ignore. */
	if (skb->nfct != NULL)
		return XT_CONTINUE;

	/* special case the untracked ct : we want the percpu object */
	if (!ct)
		ct = nf_ct_untracked_get();
	atomic_inc(&ct->ct_general.use);
	skb->nfct = &ct->ct_general;
	skb->nfctinfo = IP_CT_NEW;

	return XT_CONTINUE;
}

static unsigned int xt_ct_target_v0(struct sk_buff *skb,
				    const struct xt_action_param *par)
{
	const struct xt_ct_target_info *info = par->targinfo;
	struct nf_conn *ct = info->ct;

	return xt_ct_target(skb, ct);
}

static unsigned int xt_ct_target_v1(struct sk_buff *skb,
				    const struct xt_action_param *par)
{
	const struct xt_ct_target_info_v1 *info = par->targinfo;
	struct nf_conn *ct = info->ct;

	return xt_ct_target(skb, ct);
}

static u8 xt_ct_find_proto(const struct xt_tgchk_param *par)
{
	if (par->family == NFPROTO_IPV4) {
		const struct ipt_entry *e = par->entryinfo;

		if (e->ip.invflags & IPT_INV_PROTO)
			return 0;
		return e->ip.proto;
	} else if (par->family == NFPROTO_IPV6) {
		const struct ip6t_entry *e = par->entryinfo;

		if (e->ipv6.invflags & IP6T_INV_PROTO)
			return 0;
		return e->ipv6.proto;
	} else
		return 0;
}

static int
xt_ct_set_helper(struct nf_conn *ct, const char *helper_name,
		 const struct xt_tgchk_param *par)
{
	struct nf_conntrack_helper *helper;
	struct nf_conn_help *help;
	u8 proto;

	proto = xt_ct_find_proto(par);
	if (!proto) {
		pr_info("You must specify a L4 protocol, and not use "
			"inversions on it.\n");
		return -ENOENT;
	}

	helper = nf_conntrack_helper_try_module_get(helper_name, par->family,
						    proto);
	if (helper == NULL) {
		pr_info("No such helper \"%s\"\n", helper_name);
		return -ENOENT;
	}

	help = nf_ct_helper_ext_add(ct, helper, GFP_KERNEL);
	if (help == NULL) {
		module_put(helper->me);
		return -ENOMEM;
	}

	help->helper = helper;
	return 0;
}

#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
static void __xt_ct_tg_timeout_put(struct ctnl_timeout *timeout)
{
	typeof(nf_ct_timeout_put_hook) timeout_put;

	timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
	if (timeout_put)
		timeout_put(timeout);
}
#endif

static int
xt_ct_set_timeout(struct nf_conn *ct, const struct xt_tgchk_param *par,
		  const char *timeout_name)
{
#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
	typeof(nf_ct_timeout_find_get_hook) timeout_find_get;
	struct ctnl_timeout *timeout;
	struct nf_conn_timeout *timeout_ext;
	struct nf_conntrack_l4proto *l4proto;
	int ret = 0;
	u8 proto;

	rcu_read_lock();
	timeout_find_get = rcu_dereference(nf_ct_timeout_find_get_hook);
	if (timeout_find_get == NULL) {
		ret = -ENOENT;
		pr_info("Timeout policy base is empty\n");
		goto out;
	}

	proto = xt_ct_find_proto(par);
	if (!proto) {
		ret = -EINVAL;
		pr_info("You must specify a L4 protocol, and not use "
			"inversions on it.\n");
		goto out;
	}

	timeout = timeout_find_get(timeout_name);
	if (timeout == NULL) {
		ret = -ENOENT;
		pr_info("No such timeout policy \"%s\"\n", timeout_name);
		goto out;
	}

	if (timeout->l3num != par->family) {
		ret = -EINVAL;
		pr_info("Timeout policy `%s' can only be used by L3 protocol "
			"number %d\n", timeout_name, timeout->l3num);
		goto err_put_timeout;
	}
	/* Make sure the timeout policy matches any existing protocol tracker,
	 * otherwise default to generic.
	 */
	l4proto = __nf_ct_l4proto_find(par->family, proto);
	if (timeout->l4proto->l4proto != l4proto->l4proto) {
		ret = -EINVAL;
		pr_info("Timeout policy `%s' can only be used by L4 protocol "
			"number %d\n",
			timeout_name, timeout->l4proto->l4proto);
		goto err_put_timeout;
	}
	timeout_ext = nf_ct_timeout_ext_add(ct, timeout, GFP_ATOMIC);
	if (timeout_ext == NULL)
		ret = -ENOMEM;

err_put_timeout:
	__xt_ct_tg_timeout_put(timeout);
out:
	rcu_read_unlock();
	return ret;
#else
	return -EOPNOTSUPP;
#endif
}

static int xt_ct_tg_check(const struct xt_tgchk_param *par,
			  struct xt_ct_target_info_v1 *info)
{
	struct nf_conntrack_tuple t;
	struct nf_conn *ct;
	int ret = -EOPNOTSUPP;

	if (info->flags & XT_CT_NOTRACK) {
		ct = NULL;
		goto out;
	}

#ifndef CONFIG_NF_CONNTRACK_ZONES
	if (info->zone)
		goto err1;
#endif

	ret = nf_ct_l3proto_try_module_get(par->family);
	if (ret < 0)
		goto err1;

	memset(&t, 0, sizeof(t));
	ct = nf_conntrack_alloc(par->net, info->zone, &t, &t, GFP_KERNEL);
	ret = PTR_ERR(ct);
	if (IS_ERR(ct))
		goto err2;

	ret = 0;
	if ((info->ct_events || info->exp_events) &&
	    !nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
				  GFP_KERNEL)) {
		ret = -EINVAL;
		goto err3;
	}

	if (info->helper[0]) {
		ret = xt_ct_set_helper(ct, info->helper, par);
		if (ret < 0)
			goto err3;
	}

	if (info->timeout[0]) {
		ret = xt_ct_set_timeout(ct, par, info->timeout);
		if (ret < 0)
			goto err3;
	}

	nf_conntrack_tmpl_insert(par->net, ct);
out:
	info->ct = ct;
	return 0;

err3:
	nf_conntrack_free(ct);
err2:
	nf_ct_l3proto_module_put(par->family);
err1:
	return ret;
}

static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
{
	struct xt_ct_target_info *info = par->targinfo;
	struct xt_ct_target_info_v1 info_v1 = {
		.flags 		= info->flags,
		.zone		= info->zone,
		.ct_events	= info->ct_events,
		.exp_events	= info->exp_events,
	};
	int ret;

	if (info->flags & ~XT_CT_NOTRACK)
		return -EINVAL;

	memcpy(info_v1.helper, info->helper, sizeof(info->helper));

	ret = xt_ct_tg_check(par, &info_v1);
	if (ret < 0)
		return ret;

	info->ct = info_v1.ct;

	return ret;
}

static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
{
	struct xt_ct_target_info_v1 *info = par->targinfo;

	if (info->flags & ~XT_CT_NOTRACK)
		return -EINVAL;

	return xt_ct_tg_check(par, par->targinfo);
}

static int xt_ct_tg_check_v2(const struct xt_tgchk_param *par)
{
	struct xt_ct_target_info_v1 *info = par->targinfo;

	if (info->flags & ~XT_CT_MASK)
		return -EINVAL;

	return xt_ct_tg_check(par, par->targinfo);
}

static void xt_ct_destroy_timeout(struct nf_conn *ct)
{
#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
	struct nf_conn_timeout *timeout_ext;
	typeof(nf_ct_timeout_put_hook) timeout_put;

	rcu_read_lock();
	timeout_put = rcu_dereference(nf_ct_timeout_put_hook);

	if (timeout_put) {
		timeout_ext = nf_ct_timeout_find(ct);
		if (timeout_ext)
			timeout_put(timeout_ext->timeout);
	}
	rcu_read_unlock();
#endif
}

static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
			     struct xt_ct_target_info_v1 *info)
{
	struct nf_conn *ct = info->ct;
	struct nf_conn_help *help;

	if (ct && !nf_ct_is_untracked(ct)) {
		help = nfct_help(ct);
		if (help)
			module_put(help->helper->me);

		nf_ct_l3proto_module_put(par->family);

		xt_ct_destroy_timeout(ct);
		nf_ct_put(info->ct);
	}
}

static void xt_ct_tg_destroy_v0(const struct xt_tgdtor_param *par)
{
	struct xt_ct_target_info *info = par->targinfo;
	struct xt_ct_target_info_v1 info_v1 = {
		.flags 		= info->flags,
		.zone		= info->zone,
		.ct_events	= info->ct_events,
		.exp_events	= info->exp_events,
		.ct		= info->ct,
	};
	memcpy(info_v1.helper, info->helper, sizeof(info->helper));

	xt_ct_tg_destroy(par, &info_v1);
}

static void xt_ct_tg_destroy_v1(const struct xt_tgdtor_param *par)
{
	xt_ct_tg_destroy(par, par->targinfo);
}

static struct xt_target xt_ct_tg_reg[] __read_mostly = {
	{
		.name		= "CT",
		.family		= NFPROTO_UNSPEC,
		.targetsize	= sizeof(struct xt_ct_target_info),
		.checkentry	= xt_ct_tg_check_v0,
		.destroy	= xt_ct_tg_destroy_v0,
		.target		= xt_ct_target_v0,
		.table		= "raw",
		.me		= THIS_MODULE,
	},
	{
		.name		= "CT",
		.family		= NFPROTO_UNSPEC,
		.revision	= 1,
		.targetsize	= sizeof(struct xt_ct_target_info_v1),
		.checkentry	= xt_ct_tg_check_v1,
		.destroy	= xt_ct_tg_destroy_v1,
		.target		= xt_ct_target_v1,
		.table		= "raw",
		.me		= THIS_MODULE,
	},
	{
		.name		= "CT",
		.family		= NFPROTO_UNSPEC,
		.revision	= 2,
		.targetsize	= sizeof(struct xt_ct_target_info_v1),
		.checkentry	= xt_ct_tg_check_v2,
		.destroy	= xt_ct_tg_destroy_v1,
		.target		= xt_ct_target_v1,
		.table		= "raw",
		.me		= THIS_MODULE,
	},
};

static unsigned int
notrack_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
	/* Previously seen (loopback)? Ignore. */
	if (skb->nfct != NULL)
		return XT_CONTINUE;

	skb->nfct = &nf_ct_untracked_get()->ct_general;
	skb->nfctinfo = IP_CT_NEW;
	nf_conntrack_get(skb->nfct);

	return XT_CONTINUE;
}

static int notrack_chk(const struct xt_tgchk_param *par)
{
	if (!par->net->xt.notrack_deprecated_warning) {
		pr_info("netfilter: NOTRACK target is deprecated, "
			"use CT instead or upgrade iptables\n");
		par->net->xt.notrack_deprecated_warning = true;
	}
	return 0;
}

static struct xt_target notrack_tg_reg __read_mostly = {
	.name		= "NOTRACK",
	.revision	= 0,
	.family		= NFPROTO_UNSPEC,
	.checkentry	= notrack_chk,
	.target		= notrack_tg,
	.table		= "raw",
	.me		= THIS_MODULE,
};

static int __init xt_ct_tg_init(void)
{
	int ret;

	ret = xt_register_target(&notrack_tg_reg);
	if (ret < 0)
		return ret;

	ret = xt_register_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
	if (ret < 0) {
		xt_unregister_target(&notrack_tg_reg);
		return ret;
	}
	return 0;
}

static void __exit xt_ct_tg_exit(void)
{
	xt_unregister_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
	xt_unregister_target(&notrack_tg_reg);
}

module_init(xt_ct_tg_init);
module_exit(xt_ct_tg_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Xtables: connection tracking target");
MODULE_ALIAS("ipt_CT");
MODULE_ALIAS("ip6t_CT");
MODULE_ALIAS("ipt_NOTRACK");
MODULE_ALIAS("ip6t_NOTRACK");
Commit	Line	Data
84f3bb9a PM	1	/*
	2	* Copyright (c) 2010 Patrick McHardy <kaber@trash.net>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*/
a7fed762	8	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
84f3bb9a	9	#include <linux/module.h>
5a0e3ad6	10	#include <linux/gfp.h>
84f3bb9a	11	#include <linux/skbuff.h>
84f3bb9a PM	12	#include <linux/netfilter_ipv4/ip_tables.h>
	13	#include <linux/netfilter_ipv6/ip6_tables.h>
	14	#include <linux/netfilter/x_tables.h>
	15	#include <linux/netfilter/xt_CT.h>
	16	#include <net/netfilter/nf_conntrack.h>
eeb4cb95	17	#include <net/netfilter/nf_conntrack_l4proto.h>
84f3bb9a PM	18	#include <net/netfilter/nf_conntrack_helper.h>
84f3bb9a PM	19	#include <net/netfilter/nf_conntrack_ecache.h>
24de58f4	20	#include <net/netfilter/nf_conntrack_timeout.h>
5d0aa2cc	21	#include <net/netfilter/nf_conntrack_zones.h>
84f3bb9a	22
d52ed437	23	static inline int xt_ct_target(struct sk_buff skb, struct nf_conn ct)
84f3bb9a	24	{
84f3bb9a PM	25	/* Previously seen (loopback)? Ignore. */
	26	if (skb->nfct != NULL)
	27	return XT_CONTINUE;
	28
27e7190e ED	29	/* special case the untracked ct : we want the percpu object */
	30	if (!ct)
	31	ct = nf_ct_untracked_get();
84f3bb9a PM	32	atomic_inc(&ct->ct_general.use);
	33	skb->nfct = &ct->ct_general;
	34	skb->nfctinfo = IP_CT_NEW;
	35
	36	return XT_CONTINUE;
	37	}
	38
d52ed437	39	static unsigned int xt_ct_target_v0(struct sk_buff *skb,
24de58f4 PNA	40	const struct xt_action_param *par)
24de58f4 PNA	41	{
d52ed437	42	const struct xt_ct_target_info *info = par->targinfo;
24de58f4 PNA	43	struct nf_conn *ct = info->ct;
24de58f4 PNA	44
d52ed437 PNA	45	return xt_ct_target(skb, ct);
d52ed437 PNA	46	}
24de58f4	47
d52ed437 PNA	48	static unsigned int xt_ct_target_v1(struct sk_buff *skb,
	49	const struct xt_action_param *par)
	50	{
	51	const struct xt_ct_target_info_v1 *info = par->targinfo;
	52	struct nf_conn *ct = info->ct;
24de58f4	53
d52ed437	54	return xt_ct_target(skb, ct);
24de58f4 PNA	55	}
24de58f4 PNA	56
84f3bb9a PM	57	static u8 xt_ct_find_proto(const struct xt_tgchk_param *par)
84f3bb9a PM	58	{
076f7839	59	if (par->family == NFPROTO_IPV4) {
84f3bb9a PM	60	const struct ipt_entry *e = par->entryinfo;
	61
	62	if (e->ip.invflags & IPT_INV_PROTO)
	63	return 0;
	64	return e->ip.proto;
076f7839	65	} else if (par->family == NFPROTO_IPV6) {
84f3bb9a PM	66	const struct ip6t_entry *e = par->entryinfo;
	67
	68	if (e->ipv6.invflags & IP6T_INV_PROTO)
	69	return 0;
	70	return e->ipv6.proto;
	71	} else
	72	return 0;
	73	}
	74
236df005 PNA	75	static int
	76	xt_ct_set_helper(struct nf_conn ct, const char helper_name,
	77	const struct xt_tgchk_param *par)
	78	{
	79	struct nf_conntrack_helper *helper;
	80	struct nf_conn_help *help;
	81	u8 proto;
	82
	83	proto = xt_ct_find_proto(par);
	84	if (!proto) {
	85	pr_info("You must specify a L4 protocol, and not use "
	86	"inversions on it.\n");
	87	return -ENOENT;
	88	}
	89
	90	helper = nf_conntrack_helper_try_module_get(helper_name, par->family,
	91	proto);
	92	if (helper == NULL) {
	93	pr_info("No such helper \"%s\"\n", helper_name);
	94	return -ENOENT;
	95	}
	96
	97	help = nf_ct_helper_ext_add(ct, helper, GFP_KERNEL);
	98	if (help == NULL) {
	99	module_put(helper->me);
	100	return -ENOMEM;
	101	}
	102
	103	help->helper = helper;
	104	return 0;
	105	}
	106
ee14186f PNA	107	#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
	108	static void __xt_ct_tg_timeout_put(struct ctnl_timeout *timeout)
	109	{
	110	typeof(nf_ct_timeout_put_hook) timeout_put;
	111
	112	timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
	113	if (timeout_put)
	114	timeout_put(timeout);
	115	}
	116	#endif
	117
236df005 PNA	118	static int
	119	xt_ct_set_timeout(struct nf_conn ct, const struct xt_tgchk_param par,
	120	const char *timeout_name)
	121	{
	122	#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
	123	typeof(nf_ct_timeout_find_get_hook) timeout_find_get;
	124	struct ctnl_timeout *timeout;
	125	struct nf_conn_timeout *timeout_ext;
236df005 PNA	126	struct nf_conntrack_l4proto *l4proto;
236df005 PNA	127	int ret = 0;
0153d5a8	128	u8 proto;
236df005 PNA	129
	130	rcu_read_lock();
	131	timeout_find_get = rcu_dereference(nf_ct_timeout_find_get_hook);
	132	if (timeout_find_get == NULL) {
	133	ret = -ENOENT;
	134	pr_info("Timeout policy base is empty\n");
	135	goto out;
	136	}
	137
0153d5a8 PNA	138	proto = xt_ct_find_proto(par);
0153d5a8 PNA	139	if (!proto) {
236df005	140	ret = -EINVAL;
0153d5a8 PNA	141	pr_info("You must specify a L4 protocol, and not use "
0153d5a8 PNA	142	"inversions on it.\n");
236df005 PNA	143	goto out;
	144	}
	145
	146	timeout = timeout_find_get(timeout_name);
	147	if (timeout == NULL) {
	148	ret = -ENOENT;
	149	pr_info("No such timeout policy \"%s\"\n", timeout_name);
	150	goto out;
	151	}
	152
	153	if (timeout->l3num != par->family) {
	154	ret = -EINVAL;
	155	pr_info("Timeout policy `%s' can only be used by L3 protocol "
	156	"number %d\n", timeout_name, timeout->l3num);
	157	goto err_put_timeout;
	158	}
	159	/* Make sure the timeout policy matches any existing protocol tracker,
	160	* otherwise default to generic.
	161	*/
0153d5a8	162	l4proto = __nf_ct_l4proto_find(par->family, proto);
236df005 PNA	163	if (timeout->l4proto->l4proto != l4proto->l4proto) {
	164	ret = -EINVAL;
	165	pr_info("Timeout policy `%s' can only be used by L4 protocol "
	166	"number %d\n",
	167	timeout_name, timeout->l4proto->l4proto);
	168	goto err_put_timeout;
	169	}
	170	timeout_ext = nf_ct_timeout_ext_add(ct, timeout, GFP_ATOMIC);
	171	if (timeout_ext == NULL)
	172	ret = -ENOMEM;
	173
	174	err_put_timeout:
	175	__xt_ct_tg_timeout_put(timeout);
	176	out:
	177	rcu_read_unlock();
	178	return ret;
	179	#else
	180	return -EOPNOTSUPP;
	181	#endif
	182	}
	183
d52ed437 PNA	184	static int xt_ct_tg_check(const struct xt_tgchk_param *par,
d52ed437 PNA	185	struct xt_ct_target_info_v1 *info)
24de58f4	186	{
24de58f4	187	struct nf_conntrack_tuple t;
24de58f4	188	struct nf_conn *ct;
4610476d	189	int ret = -EOPNOTSUPP;
236df005	190
24de58f4	191	if (info->flags & XT_CT_NOTRACK) {
27e7190e	192	ct = NULL;
24de58f4 PNA	193	goto out;
	194	}
	195
	196	#ifndef CONFIG_NF_CONNTRACK_ZONES
	197	if (info->zone)
	198	goto err1;
	199	#endif
	200
	201	ret = nf_ct_l3proto_try_module_get(par->family);
	202	if (ret < 0)
	203	goto err1;
	204
	205	memset(&t, 0, sizeof(t));
	206	ct = nf_conntrack_alloc(par->net, info->zone, &t, &t, GFP_KERNEL);
	207	ret = PTR_ERR(ct);
	208	if (IS_ERR(ct))
	209	goto err2;
	210
	211	ret = 0;
	212	if ((info->ct_events \|\| info->exp_events) &&
	213	!nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
14abfa16 EL	214	GFP_KERNEL)) {
14abfa16 EL	215	ret = -EINVAL;
24de58f4	216	goto err3;
14abfa16	217	}
24de58f4 PNA	218
24de58f4 PNA	219	if (info->helper[0]) {
236df005 PNA	220	ret = xt_ct_set_helper(ct, info->helper, par);
236df005 PNA	221	if (ret < 0)
1afc5679	222	goto err3;
24de58f4 PNA	223	}
24de58f4 PNA	224
6cf51852	225	if (info->timeout[0]) {
236df005 PNA	226	ret = xt_ct_set_timeout(ct, par, info->timeout);
	227	if (ret < 0)
	228	goto err3;
24de58f4	229	}
24de58f4	230
e53376be	231	nf_conntrack_tmpl_insert(par->net, ct);
24de58f4 PNA	232	out:
	233	info->ct = ct;
	234	return 0;
	235
	236	err3:
	237	nf_conntrack_free(ct);
	238	err2:
	239	nf_ct_l3proto_module_put(par->family);
	240	err1:
	241	return ret;
	242	}
	243
d52ed437	244	static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
84f3bb9a PM	245	{
84f3bb9a PM	246	struct xt_ct_target_info *info = par->targinfo;
d52ed437 PNA	247	struct xt_ct_target_info_v1 info_v1 = {
	248	.flags = info->flags,
	249	.zone = info->zone,
	250	.ct_events = info->ct_events,
	251	.exp_events = info->exp_events,
	252	};
	253	int ret;
84f3bb9a	254
5474f57f PNA	255	if (info->flags & ~XT_CT_NOTRACK)
	256	return -EINVAL;
	257
d52ed437	258	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
84f3bb9a	259
d52ed437 PNA	260	ret = xt_ct_tg_check(par, &info_v1);
	261	if (ret < 0)
	262	return ret;
	263
	264	info->ct = info_v1.ct;
	265
	266	return ret;
	267	}
	268
	269	static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
	270	{
5474f57f PNA	271	struct xt_ct_target_info_v1 *info = par->targinfo;
	272
	273	if (info->flags & ~XT_CT_NOTRACK)
	274	return -EINVAL;
	275
	276	return xt_ct_tg_check(par, par->targinfo);
	277	}
	278
	279	static int xt_ct_tg_check_v2(const struct xt_tgchk_param *par)
	280	{
	281	struct xt_ct_target_info_v1 *info = par->targinfo;
	282
	283	if (info->flags & ~XT_CT_MASK)
	284	return -EINVAL;
	285
d52ed437	286	return xt_ct_tg_check(par, par->targinfo);
84f3bb9a PM	287	}
84f3bb9a PM	288
236df005	289	static void xt_ct_destroy_timeout(struct nf_conn *ct)
24de58f4	290	{
24de58f4 PNA	291	#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
	292	struct nf_conn_timeout *timeout_ext;
	293	typeof(nf_ct_timeout_put_hook) timeout_put;
236df005 PNA	294
	295	rcu_read_lock();
	296	timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
	297
	298	if (timeout_put) {
	299	timeout_ext = nf_ct_timeout_find(ct);
	300	if (timeout_ext)
	301	timeout_put(timeout_ext->timeout);
	302	}
	303	rcu_read_unlock();
24de58f4	304	#endif
236df005 PNA	305	}
236df005 PNA	306
d52ed437 PNA	307	static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
d52ed437 PNA	308	struct xt_ct_target_info_v1 *info)
236df005	309	{
236df005 PNA	310	struct nf_conn *ct = info->ct;
	311	struct nf_conn_help *help;
	312
27e7190e	313	if (ct && !nf_ct_is_untracked(ct)) {
24de58f4 PNA	314	help = nfct_help(ct);
	315	if (help)
	316	module_put(help->helper->me);
	317
	318	nf_ct_l3proto_module_put(par->family);
	319
236df005	320	xt_ct_destroy_timeout(ct);
27e7190e	321	nf_ct_put(info->ct);
24de58f4	322	}
d52ed437 PNA	323	}
	324
	325	static void xt_ct_tg_destroy_v0(const struct xt_tgdtor_param *par)
	326	{
	327	struct xt_ct_target_info *info = par->targinfo;
	328	struct xt_ct_target_info_v1 info_v1 = {
	329	.flags = info->flags,
	330	.zone = info->zone,
	331	.ct_events = info->ct_events,
	332	.exp_events = info->exp_events,
	333	.ct = info->ct,
	334	};
	335	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
	336
	337	xt_ct_tg_destroy(par, &info_v1);
	338	}
	339
	340	static void xt_ct_tg_destroy_v1(const struct xt_tgdtor_param *par)
	341	{
	342	xt_ct_tg_destroy(par, par->targinfo);
24de58f4 PNA	343	}
	344
	345	static struct xt_target xt_ct_tg_reg[] __read_mostly = {
	346	{
	347	.name = "CT",
	348	.family = NFPROTO_UNSPEC,
	349	.targetsize = sizeof(struct xt_ct_target_info),
	350	.checkentry = xt_ct_tg_check_v0,
	351	.destroy = xt_ct_tg_destroy_v0,
	352	.target = xt_ct_target_v0,
	353	.table = "raw",
	354	.me = THIS_MODULE,
	355	},
	356	{
	357	.name = "CT",
	358	.family = NFPROTO_UNSPEC,
	359	.revision = 1,
	360	.targetsize = sizeof(struct xt_ct_target_info_v1),
	361	.checkentry = xt_ct_tg_check_v1,
	362	.destroy = xt_ct_tg_destroy_v1,
	363	.target = xt_ct_target_v1,
	364	.table = "raw",
	365	.me = THIS_MODULE,
	366	},
5474f57f PNA	367	{
	368	.name = "CT",
	369	.family = NFPROTO_UNSPEC,
	370	.revision = 2,
	371	.targetsize = sizeof(struct xt_ct_target_info_v1),
	372	.checkentry = xt_ct_tg_check_v2,
	373	.destroy = xt_ct_tg_destroy_v1,
	374	.target = xt_ct_target_v1,
	375	.table = "raw",
	376	.me = THIS_MODULE,
	377	},
84f3bb9a PM	378	};
84f3bb9a PM	379
10db9069 PNA	380	static unsigned int
	381	notrack_tg(struct sk_buff skb, const struct xt_action_param par)
	382	{
	383	/* Previously seen (loopback)? Ignore. */
	384	if (skb->nfct != NULL)
	385	return XT_CONTINUE;
	386
	387	skb->nfct = &nf_ct_untracked_get()->ct_general;
	388	skb->nfctinfo = IP_CT_NEW;
	389	nf_conntrack_get(skb->nfct);
	390
	391	return XT_CONTINUE;
	392	}
	393
	394	static int notrack_chk(const struct xt_tgchk_param *par)
	395	{
	396	if (!par->net->xt.notrack_deprecated_warning) {
	397	pr_info("netfilter: NOTRACK target is deprecated, "
	398	"use CT instead or upgrade iptables\n");
	399	par->net->xt.notrack_deprecated_warning = true;
	400	}
	401	return 0;
	402	}
	403
	404	static struct xt_target notrack_tg_reg __read_mostly = {
	405	.name = "NOTRACK",
	406	.revision = 0,
	407	.family = NFPROTO_UNSPEC,
	408	.checkentry = notrack_chk,
	409	.target = notrack_tg,
	410	.table = "raw",
	411	.me = THIS_MODULE,
	412	};
	413
84f3bb9a PM	414	static int __init xt_ct_tg_init(void)
84f3bb9a PM	415	{
10db9069 PNA	416	int ret;
	417
	418	ret = xt_register_target(&notrack_tg_reg);
	419	if (ret < 0)
	420	return ret;
	421
	422	ret = xt_register_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
	423	if (ret < 0) {
	424	xt_unregister_target(&notrack_tg_reg);
	425	return ret;
	426	}
	427	return 0;
84f3bb9a PM	428	}
	429
	430	static void __exit xt_ct_tg_exit(void)
	431	{
24de58f4	432	xt_unregister_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
10db9069	433	xt_unregister_target(&notrack_tg_reg);
84f3bb9a PM	434	}
	435
	436	module_init(xt_ct_tg_init);
	437	module_exit(xt_ct_tg_exit);
	438
	439	MODULE_LICENSE("GPL");
	440	MODULE_DESCRIPTION("Xtables: connection tracking target");
	441	MODULE_ALIAS("ipt_CT");
	442	MODULE_ALIAS("ip6t_CT");
10db9069 PNA	443	MODULE_ALIAS("ipt_NOTRACK");
10db9069 PNA	444	MODULE_ALIAS("ip6t_NOTRACK");