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v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (c) 2010 Patrick McHardy <kaber@trash.net>
 
 
 
 
  4 */
  5#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  6#include <linux/module.h>
  7#include <linux/gfp.h>
  8#include <linux/skbuff.h>
  9#include <linux/netfilter_ipv4/ip_tables.h>
 10#include <linux/netfilter_ipv6/ip6_tables.h>
 11#include <linux/netfilter/x_tables.h>
 12#include <linux/netfilter/xt_CT.h>
 13#include <net/netfilter/nf_conntrack.h>
 14#include <net/netfilter/nf_conntrack_l4proto.h>
 15#include <net/netfilter/nf_conntrack_helper.h>
 16#include <net/netfilter/nf_conntrack_ecache.h>
 17#include <net/netfilter/nf_conntrack_timeout.h>
 18#include <net/netfilter/nf_conntrack_zones.h>
 19
 20static inline int xt_ct_target(struct sk_buff *skb, struct nf_conn *ct)
 21{
 22	/* Previously seen (loopback)? Ignore. */
 23	if (skb->_nfct != 0)
 24		return XT_CONTINUE;
 25
 26	if (ct) {
 27		atomic_inc(&ct->ct_general.use);
 28		nf_ct_set(skb, ct, IP_CT_NEW);
 29	} else {
 30		nf_ct_set(skb, ct, IP_CT_UNTRACKED);
 31	}
 32
 33	return XT_CONTINUE;
 34}
 35
 36static unsigned int xt_ct_target_v0(struct sk_buff *skb,
 37				    const struct xt_action_param *par)
 38{
 39	const struct xt_ct_target_info *info = par->targinfo;
 40	struct nf_conn *ct = info->ct;
 41
 42	return xt_ct_target(skb, ct);
 43}
 44
 45static unsigned int xt_ct_target_v1(struct sk_buff *skb,
 46				    const struct xt_action_param *par)
 47{
 48	const struct xt_ct_target_info_v1 *info = par->targinfo;
 49	struct nf_conn *ct = info->ct;
 50
 51	return xt_ct_target(skb, ct);
 52}
 53
 54static u8 xt_ct_find_proto(const struct xt_tgchk_param *par)
 55{
 56	if (par->family == NFPROTO_IPV4) {
 57		const struct ipt_entry *e = par->entryinfo;
 58
 59		if (e->ip.invflags & IPT_INV_PROTO)
 60			return 0;
 61		return e->ip.proto;
 62	} else if (par->family == NFPROTO_IPV6) {
 63		const struct ip6t_entry *e = par->entryinfo;
 64
 65		if (e->ipv6.invflags & IP6T_INV_PROTO)
 66			return 0;
 67		return e->ipv6.proto;
 68	} else
 69		return 0;
 70}
 71
 72static int
 73xt_ct_set_helper(struct nf_conn *ct, const char *helper_name,
 74		 const struct xt_tgchk_param *par)
 75{
 76	struct nf_conntrack_helper *helper;
 77	struct nf_conn_help *help;
 78	u8 proto;
 79
 80	proto = xt_ct_find_proto(par);
 81	if (!proto) {
 82		pr_info_ratelimited("You must specify a L4 protocol and not use inversions on it\n");
 83		return -ENOENT;
 84	}
 85
 86	helper = nf_conntrack_helper_try_module_get(helper_name, par->family,
 87						    proto);
 88	if (helper == NULL) {
 89		pr_info_ratelimited("No such helper \"%s\"\n", helper_name);
 90		return -ENOENT;
 91	}
 92
 93	help = nf_ct_helper_ext_add(ct, GFP_KERNEL);
 94	if (help == NULL) {
 95		nf_conntrack_helper_put(helper);
 96		return -ENOMEM;
 97	}
 98
 99	help->helper = helper;
100	return 0;
101}
102
 
 
 
 
 
 
 
 
 
 
 
103static int
104xt_ct_set_timeout(struct nf_conn *ct, const struct xt_tgchk_param *par,
105		  const char *timeout_name)
106{
107#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
 
108	const struct nf_conntrack_l4proto *l4proto;
 
 
 
 
109	u8 proto;
110
 
 
 
 
 
 
 
 
111	proto = xt_ct_find_proto(par);
112	if (!proto) {
113		pr_info_ratelimited("You must specify a L4 protocol and not "
114				    "use inversions on it");
115		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
116	}
117	l4proto = nf_ct_l4proto_find(proto);
118	return nf_ct_set_timeout(par->net, ct, par->family, l4proto->l4proto,
119				 timeout_name);
120
 
 
 
 
 
 
 
 
 
 
121#else
122	return -EOPNOTSUPP;
123#endif
124}
125
126static u16 xt_ct_flags_to_dir(const struct xt_ct_target_info_v1 *info)
127{
128	switch (info->flags & (XT_CT_ZONE_DIR_ORIG |
129			       XT_CT_ZONE_DIR_REPL)) {
130	case XT_CT_ZONE_DIR_ORIG:
131		return NF_CT_ZONE_DIR_ORIG;
132	case XT_CT_ZONE_DIR_REPL:
133		return NF_CT_ZONE_DIR_REPL;
134	default:
135		return NF_CT_DEFAULT_ZONE_DIR;
136	}
137}
138
139static int xt_ct_tg_check(const struct xt_tgchk_param *par,
140			  struct xt_ct_target_info_v1 *info)
141{
142	struct nf_conntrack_zone zone;
143	struct nf_conn_help *help;
144	struct nf_conn *ct;
145	int ret = -EOPNOTSUPP;
146
147	if (info->flags & XT_CT_NOTRACK) {
148		ct = NULL;
149		goto out;
150	}
151
152#ifndef CONFIG_NF_CONNTRACK_ZONES
153	if (info->zone || info->flags & (XT_CT_ZONE_DIR_ORIG |
154					 XT_CT_ZONE_DIR_REPL |
155					 XT_CT_ZONE_MARK))
156		goto err1;
157#endif
158
159	ret = nf_ct_netns_get(par->net, par->family);
160	if (ret < 0)
161		goto err1;
162
163	memset(&zone, 0, sizeof(zone));
164	zone.id = info->zone;
165	zone.dir = xt_ct_flags_to_dir(info);
166	if (info->flags & XT_CT_ZONE_MARK)
167		zone.flags |= NF_CT_FLAG_MARK;
168
169	ct = nf_ct_tmpl_alloc(par->net, &zone, GFP_KERNEL);
170	if (!ct) {
171		ret = -ENOMEM;
172		goto err2;
173	}
174
 
175	if ((info->ct_events || info->exp_events) &&
176	    !nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
177				  GFP_KERNEL)) {
178		ret = -EINVAL;
179		goto err3;
180	}
181
182	if (info->helper[0]) {
183		if (strnlen(info->helper, sizeof(info->helper)) == sizeof(info->helper)) {
184			ret = -ENAMETOOLONG;
185			goto err3;
186		}
187
188		ret = xt_ct_set_helper(ct, info->helper, par);
189		if (ret < 0)
190			goto err3;
191	}
192
193	if (info->timeout[0]) {
194		if (strnlen(info->timeout, sizeof(info->timeout)) == sizeof(info->timeout)) {
195			ret = -ENAMETOOLONG;
196			goto err4;
197		}
198
199		ret = xt_ct_set_timeout(ct, par, info->timeout);
200		if (ret < 0)
201			goto err4;
202	}
203	__set_bit(IPS_CONFIRMED_BIT, &ct->status);
204	nf_conntrack_get(&ct->ct_general);
205out:
206	info->ct = ct;
207	return 0;
208
209err4:
210	help = nfct_help(ct);
211	if (help)
212		nf_conntrack_helper_put(help->helper);
213err3:
214	nf_ct_tmpl_free(ct);
215err2:
216	nf_ct_netns_put(par->net, par->family);
217err1:
218	return ret;
219}
220
221static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
222{
223	struct xt_ct_target_info *info = par->targinfo;
224	struct xt_ct_target_info_v1 info_v1 = {
225		.flags 		= info->flags,
226		.zone		= info->zone,
227		.ct_events	= info->ct_events,
228		.exp_events	= info->exp_events,
229	};
230	int ret;
231
232	if (info->flags & ~XT_CT_NOTRACK)
233		return -EINVAL;
234
235	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
236
237	ret = xt_ct_tg_check(par, &info_v1);
238	if (ret < 0)
239		return ret;
240
241	info->ct = info_v1.ct;
242
243	return ret;
244}
245
246static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
247{
248	struct xt_ct_target_info_v1 *info = par->targinfo;
249
250	if (info->flags & ~XT_CT_NOTRACK)
251		return -EINVAL;
252
253	return xt_ct_tg_check(par, par->targinfo);
254}
255
256static int xt_ct_tg_check_v2(const struct xt_tgchk_param *par)
257{
258	struct xt_ct_target_info_v1 *info = par->targinfo;
259
260	if (info->flags & ~XT_CT_MASK)
261		return -EINVAL;
262
263	return xt_ct_tg_check(par, par->targinfo);
264}
265
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
266static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
267			     struct xt_ct_target_info_v1 *info)
268{
269	struct nf_conn *ct = info->ct;
270	struct nf_conn_help *help;
271
272	if (ct) {
273		help = nfct_help(ct);
274		if (help)
275			nf_conntrack_helper_put(help->helper);
276
277		nf_ct_netns_put(par->net, par->family);
278
279		nf_ct_destroy_timeout(ct);
280		nf_ct_put(info->ct);
281	}
282}
283
284static void xt_ct_tg_destroy_v0(const struct xt_tgdtor_param *par)
285{
286	struct xt_ct_target_info *info = par->targinfo;
287	struct xt_ct_target_info_v1 info_v1 = {
288		.flags 		= info->flags,
289		.zone		= info->zone,
290		.ct_events	= info->ct_events,
291		.exp_events	= info->exp_events,
292		.ct		= info->ct,
293	};
294	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
295
296	xt_ct_tg_destroy(par, &info_v1);
297}
298
299static void xt_ct_tg_destroy_v1(const struct xt_tgdtor_param *par)
300{
301	xt_ct_tg_destroy(par, par->targinfo);
302}
303
304static struct xt_target xt_ct_tg_reg[] __read_mostly = {
305	{
306		.name		= "CT",
307		.family		= NFPROTO_UNSPEC,
308		.targetsize	= sizeof(struct xt_ct_target_info),
309		.usersize	= offsetof(struct xt_ct_target_info, ct),
310		.checkentry	= xt_ct_tg_check_v0,
311		.destroy	= xt_ct_tg_destroy_v0,
312		.target		= xt_ct_target_v0,
313		.table		= "raw",
314		.me		= THIS_MODULE,
315	},
316	{
317		.name		= "CT",
318		.family		= NFPROTO_UNSPEC,
319		.revision	= 1,
320		.targetsize	= sizeof(struct xt_ct_target_info_v1),
321		.usersize	= offsetof(struct xt_ct_target_info, ct),
322		.checkentry	= xt_ct_tg_check_v1,
323		.destroy	= xt_ct_tg_destroy_v1,
324		.target		= xt_ct_target_v1,
325		.table		= "raw",
326		.me		= THIS_MODULE,
327	},
328	{
329		.name		= "CT",
330		.family		= NFPROTO_UNSPEC,
331		.revision	= 2,
332		.targetsize	= sizeof(struct xt_ct_target_info_v1),
333		.usersize	= offsetof(struct xt_ct_target_info, ct),
334		.checkentry	= xt_ct_tg_check_v2,
335		.destroy	= xt_ct_tg_destroy_v1,
336		.target		= xt_ct_target_v1,
337		.table		= "raw",
338		.me		= THIS_MODULE,
339	},
340};
341
342static unsigned int
343notrack_tg(struct sk_buff *skb, const struct xt_action_param *par)
344{
345	/* Previously seen (loopback)? Ignore. */
346	if (skb->_nfct != 0)
347		return XT_CONTINUE;
348
349	nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
350
351	return XT_CONTINUE;
352}
353
354static int notrack_chk(const struct xt_tgchk_param *par)
355{
356	if (!par->net->xt.notrack_deprecated_warning) {
357		pr_info("netfilter: NOTRACK target is deprecated, "
358			"use CT instead or upgrade iptables\n");
359		par->net->xt.notrack_deprecated_warning = true;
360	}
361	return 0;
362}
363
364static struct xt_target notrack_tg_reg __read_mostly = {
365	.name		= "NOTRACK",
366	.revision	= 0,
367	.family		= NFPROTO_UNSPEC,
368	.checkentry	= notrack_chk,
369	.target		= notrack_tg,
370	.table		= "raw",
371	.me		= THIS_MODULE,
372};
373
374static int __init xt_ct_tg_init(void)
375{
376	int ret;
377
378	ret = xt_register_target(&notrack_tg_reg);
379	if (ret < 0)
380		return ret;
381
382	ret = xt_register_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
383	if (ret < 0) {
384		xt_unregister_target(&notrack_tg_reg);
385		return ret;
386	}
387	return 0;
388}
389
390static void __exit xt_ct_tg_exit(void)
391{
392	xt_unregister_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
393	xt_unregister_target(&notrack_tg_reg);
394}
395
396module_init(xt_ct_tg_init);
397module_exit(xt_ct_tg_exit);
398
399MODULE_LICENSE("GPL");
400MODULE_DESCRIPTION("Xtables: connection tracking target");
401MODULE_ALIAS("ipt_CT");
402MODULE_ALIAS("ip6t_CT");
403MODULE_ALIAS("ipt_NOTRACK");
404MODULE_ALIAS("ip6t_NOTRACK");
v4.17
 
  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 */
  8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  9#include <linux/module.h>
 10#include <linux/gfp.h>
 11#include <linux/skbuff.h>
 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>
 17#include <net/netfilter/nf_conntrack_l4proto.h>
 18#include <net/netfilter/nf_conntrack_helper.h>
 19#include <net/netfilter/nf_conntrack_ecache.h>
 20#include <net/netfilter/nf_conntrack_timeout.h>
 21#include <net/netfilter/nf_conntrack_zones.h>
 22
 23static inline int xt_ct_target(struct sk_buff *skb, struct nf_conn *ct)
 24{
 25	/* Previously seen (loopback)? Ignore. */
 26	if (skb->_nfct != 0)
 27		return XT_CONTINUE;
 28
 29	if (ct) {
 30		atomic_inc(&ct->ct_general.use);
 31		nf_ct_set(skb, ct, IP_CT_NEW);
 32	} else {
 33		nf_ct_set(skb, ct, IP_CT_UNTRACKED);
 34	}
 35
 36	return XT_CONTINUE;
 37}
 38
 39static unsigned int xt_ct_target_v0(struct sk_buff *skb,
 40				    const struct xt_action_param *par)
 41{
 42	const struct xt_ct_target_info *info = par->targinfo;
 43	struct nf_conn *ct = info->ct;
 44
 45	return xt_ct_target(skb, ct);
 46}
 47
 48static 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;
 53
 54	return xt_ct_target(skb, ct);
 55}
 56
 57static u8 xt_ct_find_proto(const struct xt_tgchk_param *par)
 58{
 59	if (par->family == NFPROTO_IPV4) {
 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;
 65	} else if (par->family == NFPROTO_IPV6) {
 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
 75static int
 76xt_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_ratelimited("You must specify a L4 protocol and not use inversions on it\n");
 86		return -ENOENT;
 87	}
 88
 89	helper = nf_conntrack_helper_try_module_get(helper_name, par->family,
 90						    proto);
 91	if (helper == NULL) {
 92		pr_info_ratelimited("No such helper \"%s\"\n", helper_name);
 93		return -ENOENT;
 94	}
 95
 96	help = nf_ct_helper_ext_add(ct, helper, GFP_KERNEL);
 97	if (help == NULL) {
 98		nf_conntrack_helper_put(helper);
 99		return -ENOMEM;
100	}
101
102	help->helper = helper;
103	return 0;
104}
105
106#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
107static void __xt_ct_tg_timeout_put(struct ctnl_timeout *timeout)
108{
109	typeof(nf_ct_timeout_put_hook) timeout_put;
110
111	timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
112	if (timeout_put)
113		timeout_put(timeout);
114}
115#endif
116
117static int
118xt_ct_set_timeout(struct nf_conn *ct, const struct xt_tgchk_param *par,
119		  const char *timeout_name)
120{
121#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
122	typeof(nf_ct_timeout_find_get_hook) timeout_find_get;
123	const struct nf_conntrack_l4proto *l4proto;
124	struct ctnl_timeout *timeout;
125	struct nf_conn_timeout *timeout_ext;
126	const char *errmsg = NULL;
127	int ret = 0;
128	u8 proto;
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		errmsg = "Timeout policy base is empty";
135		goto out;
136	}
137
138	proto = xt_ct_find_proto(par);
139	if (!proto) {
140		ret = -EINVAL;
141		errmsg = "You must specify a L4 protocol and not use inversions on it";
142		goto out;
143	}
144
145	timeout = timeout_find_get(par->net, timeout_name);
146	if (timeout == NULL) {
147		ret = -ENOENT;
148		pr_info_ratelimited("No such timeout policy \"%s\"\n",
149				    timeout_name);
150		goto out;
151	}
152
153	if (timeout->l3num != par->family) {
154		ret = -EINVAL;
155		pr_info_ratelimited("Timeout policy `%s' can only be used by L%d protocol number %d\n",
156				    timeout_name, 3, 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	 */
162	l4proto = __nf_ct_l4proto_find(par->family, proto);
163	if (timeout->l4proto->l4proto != l4proto->l4proto) {
164		ret = -EINVAL;
165		pr_info_ratelimited("Timeout policy `%s' can only be used by L%d protocol number %d\n",
166				    timeout_name, 4, timeout->l4proto->l4proto);
167		goto err_put_timeout;
168	}
169	timeout_ext = nf_ct_timeout_ext_add(ct, timeout, GFP_ATOMIC);
170	if (!timeout_ext) {
171		ret = -ENOMEM;
172		goto err_put_timeout;
173	}
 
 
 
174
175	rcu_read_unlock();
176	return ret;
177
178err_put_timeout:
179	__xt_ct_tg_timeout_put(timeout);
180out:
181	rcu_read_unlock();
182	if (errmsg)
183		pr_info_ratelimited("%s\n", errmsg);
184	return ret;
185#else
186	return -EOPNOTSUPP;
187#endif
188}
189
190static u16 xt_ct_flags_to_dir(const struct xt_ct_target_info_v1 *info)
191{
192	switch (info->flags & (XT_CT_ZONE_DIR_ORIG |
193			       XT_CT_ZONE_DIR_REPL)) {
194	case XT_CT_ZONE_DIR_ORIG:
195		return NF_CT_ZONE_DIR_ORIG;
196	case XT_CT_ZONE_DIR_REPL:
197		return NF_CT_ZONE_DIR_REPL;
198	default:
199		return NF_CT_DEFAULT_ZONE_DIR;
200	}
201}
202
203static int xt_ct_tg_check(const struct xt_tgchk_param *par,
204			  struct xt_ct_target_info_v1 *info)
205{
206	struct nf_conntrack_zone zone;
207	struct nf_conn_help *help;
208	struct nf_conn *ct;
209	int ret = -EOPNOTSUPP;
210
211	if (info->flags & XT_CT_NOTRACK) {
212		ct = NULL;
213		goto out;
214	}
215
216#ifndef CONFIG_NF_CONNTRACK_ZONES
217	if (info->zone || info->flags & (XT_CT_ZONE_DIR_ORIG |
218					 XT_CT_ZONE_DIR_REPL |
219					 XT_CT_ZONE_MARK))
220		goto err1;
221#endif
222
223	ret = nf_ct_netns_get(par->net, par->family);
224	if (ret < 0)
225		goto err1;
226
227	memset(&zone, 0, sizeof(zone));
228	zone.id = info->zone;
229	zone.dir = xt_ct_flags_to_dir(info);
230	if (info->flags & XT_CT_ZONE_MARK)
231		zone.flags |= NF_CT_FLAG_MARK;
232
233	ct = nf_ct_tmpl_alloc(par->net, &zone, GFP_KERNEL);
234	if (!ct) {
235		ret = -ENOMEM;
236		goto err2;
237	}
238
239	ret = 0;
240	if ((info->ct_events || info->exp_events) &&
241	    !nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
242				  GFP_KERNEL)) {
243		ret = -EINVAL;
244		goto err3;
245	}
246
247	if (info->helper[0]) {
 
 
 
 
 
248		ret = xt_ct_set_helper(ct, info->helper, par);
249		if (ret < 0)
250			goto err3;
251	}
252
253	if (info->timeout[0]) {
 
 
 
 
 
254		ret = xt_ct_set_timeout(ct, par, info->timeout);
255		if (ret < 0)
256			goto err4;
257	}
258	__set_bit(IPS_CONFIRMED_BIT, &ct->status);
259	nf_conntrack_get(&ct->ct_general);
260out:
261	info->ct = ct;
262	return 0;
263
264err4:
265	help = nfct_help(ct);
266	if (help)
267		nf_conntrack_helper_put(help->helper);
268err3:
269	nf_ct_tmpl_free(ct);
270err2:
271	nf_ct_netns_put(par->net, par->family);
272err1:
273	return ret;
274}
275
276static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
277{
278	struct xt_ct_target_info *info = par->targinfo;
279	struct xt_ct_target_info_v1 info_v1 = {
280		.flags 		= info->flags,
281		.zone		= info->zone,
282		.ct_events	= info->ct_events,
283		.exp_events	= info->exp_events,
284	};
285	int ret;
286
287	if (info->flags & ~XT_CT_NOTRACK)
288		return -EINVAL;
289
290	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
291
292	ret = xt_ct_tg_check(par, &info_v1);
293	if (ret < 0)
294		return ret;
295
296	info->ct = info_v1.ct;
297
298	return ret;
299}
300
301static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
302{
303	struct xt_ct_target_info_v1 *info = par->targinfo;
304
305	if (info->flags & ~XT_CT_NOTRACK)
306		return -EINVAL;
307
308	return xt_ct_tg_check(par, par->targinfo);
309}
310
311static int xt_ct_tg_check_v2(const struct xt_tgchk_param *par)
312{
313	struct xt_ct_target_info_v1 *info = par->targinfo;
314
315	if (info->flags & ~XT_CT_MASK)
316		return -EINVAL;
317
318	return xt_ct_tg_check(par, par->targinfo);
319}
320
321static void xt_ct_destroy_timeout(struct nf_conn *ct)
322{
323#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
324	struct nf_conn_timeout *timeout_ext;
325	typeof(nf_ct_timeout_put_hook) timeout_put;
326
327	rcu_read_lock();
328	timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
329
330	if (timeout_put) {
331		timeout_ext = nf_ct_timeout_find(ct);
332		if (timeout_ext) {
333			timeout_put(timeout_ext->timeout);
334			RCU_INIT_POINTER(timeout_ext->timeout, NULL);
335		}
336	}
337	rcu_read_unlock();
338#endif
339}
340
341static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
342			     struct xt_ct_target_info_v1 *info)
343{
344	struct nf_conn *ct = info->ct;
345	struct nf_conn_help *help;
346
347	if (ct) {
348		help = nfct_help(ct);
349		if (help)
350			nf_conntrack_helper_put(help->helper);
351
352		nf_ct_netns_put(par->net, par->family);
353
354		xt_ct_destroy_timeout(ct);
355		nf_ct_put(info->ct);
356	}
357}
358
359static void xt_ct_tg_destroy_v0(const struct xt_tgdtor_param *par)
360{
361	struct xt_ct_target_info *info = par->targinfo;
362	struct xt_ct_target_info_v1 info_v1 = {
363		.flags 		= info->flags,
364		.zone		= info->zone,
365		.ct_events	= info->ct_events,
366		.exp_events	= info->exp_events,
367		.ct		= info->ct,
368	};
369	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
370
371	xt_ct_tg_destroy(par, &info_v1);
372}
373
374static void xt_ct_tg_destroy_v1(const struct xt_tgdtor_param *par)
375{
376	xt_ct_tg_destroy(par, par->targinfo);
377}
378
379static struct xt_target xt_ct_tg_reg[] __read_mostly = {
380	{
381		.name		= "CT",
382		.family		= NFPROTO_UNSPEC,
383		.targetsize	= sizeof(struct xt_ct_target_info),
384		.usersize	= offsetof(struct xt_ct_target_info, ct),
385		.checkentry	= xt_ct_tg_check_v0,
386		.destroy	= xt_ct_tg_destroy_v0,
387		.target		= xt_ct_target_v0,
388		.table		= "raw",
389		.me		= THIS_MODULE,
390	},
391	{
392		.name		= "CT",
393		.family		= NFPROTO_UNSPEC,
394		.revision	= 1,
395		.targetsize	= sizeof(struct xt_ct_target_info_v1),
396		.usersize	= offsetof(struct xt_ct_target_info, ct),
397		.checkentry	= xt_ct_tg_check_v1,
398		.destroy	= xt_ct_tg_destroy_v1,
399		.target		= xt_ct_target_v1,
400		.table		= "raw",
401		.me		= THIS_MODULE,
402	},
403	{
404		.name		= "CT",
405		.family		= NFPROTO_UNSPEC,
406		.revision	= 2,
407		.targetsize	= sizeof(struct xt_ct_target_info_v1),
408		.usersize	= offsetof(struct xt_ct_target_info, ct),
409		.checkentry	= xt_ct_tg_check_v2,
410		.destroy	= xt_ct_tg_destroy_v1,
411		.target		= xt_ct_target_v1,
412		.table		= "raw",
413		.me		= THIS_MODULE,
414	},
415};
416
417static unsigned int
418notrack_tg(struct sk_buff *skb, const struct xt_action_param *par)
419{
420	/* Previously seen (loopback)? Ignore. */
421	if (skb->_nfct != 0)
422		return XT_CONTINUE;
423
424	nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
425
426	return XT_CONTINUE;
427}
428
429static int notrack_chk(const struct xt_tgchk_param *par)
430{
431	if (!par->net->xt.notrack_deprecated_warning) {
432		pr_info("netfilter: NOTRACK target is deprecated, "
433			"use CT instead or upgrade iptables\n");
434		par->net->xt.notrack_deprecated_warning = true;
435	}
436	return 0;
437}
438
439static struct xt_target notrack_tg_reg __read_mostly = {
440	.name		= "NOTRACK",
441	.revision	= 0,
442	.family		= NFPROTO_UNSPEC,
443	.checkentry	= notrack_chk,
444	.target		= notrack_tg,
445	.table		= "raw",
446	.me		= THIS_MODULE,
447};
448
449static int __init xt_ct_tg_init(void)
450{
451	int ret;
452
453	ret = xt_register_target(&notrack_tg_reg);
454	if (ret < 0)
455		return ret;
456
457	ret = xt_register_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
458	if (ret < 0) {
459		xt_unregister_target(&notrack_tg_reg);
460		return ret;
461	}
462	return 0;
463}
464
465static void __exit xt_ct_tg_exit(void)
466{
467	xt_unregister_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
468	xt_unregister_target(&notrack_tg_reg);
469}
470
471module_init(xt_ct_tg_init);
472module_exit(xt_ct_tg_exit);
473
474MODULE_LICENSE("GPL");
475MODULE_DESCRIPTION("Xtables: connection tracking target");
476MODULE_ALIAS("ipt_CT");
477MODULE_ALIAS("ip6t_CT");
478MODULE_ALIAS("ipt_NOTRACK");
479MODULE_ALIAS("ip6t_NOTRACK");