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v4.10.11
 
  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 != NULL)
 27		return XT_CONTINUE;
 28
 29	/* special case the untracked ct : we want the percpu object */
 30	if (!ct)
 31		ct = nf_ct_untracked_get();
 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
 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("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
107#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
108static 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
118static int
119xt_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;
126	struct nf_conntrack_l4proto *l4proto;
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		pr_info("Timeout policy base is empty\n");
135		goto out;
136	}
137
138	proto = xt_ct_find_proto(par);
139	if (!proto) {
140		ret = -EINVAL;
141		pr_info("You must specify a L4 protocol, and not use "
142			"inversions on it.\n");
143		goto out;
144	}
145
146	timeout = timeout_find_get(par->net, 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	 */
162	l4proto = __nf_ct_l4proto_find(par->family, proto);
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	rcu_read_unlock();
175	return ret;
176
177err_put_timeout:
178	__xt_ct_tg_timeout_put(timeout);
179out:
180	rcu_read_unlock();
181	return ret;
182#else
183	return -EOPNOTSUPP;
184#endif
185}
186
187static u16 xt_ct_flags_to_dir(const struct xt_ct_target_info_v1 *info)
188{
189	switch (info->flags & (XT_CT_ZONE_DIR_ORIG |
190			       XT_CT_ZONE_DIR_REPL)) {
191	case XT_CT_ZONE_DIR_ORIG:
192		return NF_CT_ZONE_DIR_ORIG;
193	case XT_CT_ZONE_DIR_REPL:
194		return NF_CT_ZONE_DIR_REPL;
195	default:
196		return NF_CT_DEFAULT_ZONE_DIR;
197	}
198}
199
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
200static int xt_ct_tg_check(const struct xt_tgchk_param *par,
201			  struct xt_ct_target_info_v1 *info)
202{
203	struct nf_conntrack_zone zone;
 
204	struct nf_conn *ct;
205	int ret = -EOPNOTSUPP;
206
207	if (info->flags & XT_CT_NOTRACK) {
208		ct = NULL;
209		goto out;
210	}
211
212#ifndef CONFIG_NF_CONNTRACK_ZONES
213	if (info->zone || info->flags & (XT_CT_ZONE_DIR_ORIG |
214					 XT_CT_ZONE_DIR_REPL |
215					 XT_CT_ZONE_MARK))
216		goto err1;
217#endif
218
219	ret = nf_ct_netns_get(par->net, par->family);
220	if (ret < 0)
221		goto err1;
222
223	memset(&zone, 0, sizeof(zone));
224	zone.id = info->zone;
225	zone.dir = xt_ct_flags_to_dir(info);
226	if (info->flags & XT_CT_ZONE_MARK)
227		zone.flags |= NF_CT_FLAG_MARK;
228
229	ct = nf_ct_tmpl_alloc(par->net, &zone, GFP_KERNEL);
230	if (!ct) {
231		ret = -ENOMEM;
232		goto err2;
233	}
234
235	ret = 0;
236	if ((info->ct_events || info->exp_events) &&
237	    !nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
238				  GFP_KERNEL)) {
239		ret = -EINVAL;
240		goto err3;
241	}
242
243	if (info->helper[0]) {
 
 
 
 
 
244		ret = xt_ct_set_helper(ct, info->helper, par);
245		if (ret < 0)
246			goto err3;
247	}
248
249	if (info->timeout[0]) {
 
 
 
 
 
250		ret = xt_ct_set_timeout(ct, par, info->timeout);
251		if (ret < 0)
252			goto err3;
253	}
254	__set_bit(IPS_CONFIRMED_BIT, &ct->status);
255	nf_conntrack_get(&ct->ct_general);
256out:
257	info->ct = ct;
258	return 0;
259
 
 
 
260err3:
261	nf_ct_tmpl_free(ct);
262err2:
263	nf_ct_netns_put(par->net, par->family);
264err1:
265	return ret;
266}
267
268static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
269{
270	struct xt_ct_target_info *info = par->targinfo;
271	struct xt_ct_target_info_v1 info_v1 = {
272		.flags 		= info->flags,
273		.zone		= info->zone,
274		.ct_events	= info->ct_events,
275		.exp_events	= info->exp_events,
276	};
277	int ret;
278
279	if (info->flags & ~XT_CT_NOTRACK)
280		return -EINVAL;
281
282	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
283
284	ret = xt_ct_tg_check(par, &info_v1);
285	if (ret < 0)
286		return ret;
287
288	info->ct = info_v1.ct;
289
290	return ret;
291}
292
293static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
294{
295	struct xt_ct_target_info_v1 *info = par->targinfo;
296
297	if (info->flags & ~XT_CT_NOTRACK)
298		return -EINVAL;
299
300	return xt_ct_tg_check(par, par->targinfo);
301}
302
303static int xt_ct_tg_check_v2(const struct xt_tgchk_param *par)
304{
305	struct xt_ct_target_info_v1 *info = par->targinfo;
306
307	if (info->flags & ~XT_CT_MASK)
308		return -EINVAL;
309
310	return xt_ct_tg_check(par, par->targinfo);
311}
312
313static void xt_ct_destroy_timeout(struct nf_conn *ct)
314{
315#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
316	struct nf_conn_timeout *timeout_ext;
317	typeof(nf_ct_timeout_put_hook) timeout_put;
318
319	rcu_read_lock();
320	timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
321
322	if (timeout_put) {
323		timeout_ext = nf_ct_timeout_find(ct);
324		if (timeout_ext) {
325			timeout_put(timeout_ext->timeout);
326			RCU_INIT_POINTER(timeout_ext->timeout, NULL);
327		}
328	}
329	rcu_read_unlock();
330#endif
331}
332
333static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
334			     struct xt_ct_target_info_v1 *info)
335{
336	struct nf_conn *ct = info->ct;
337	struct nf_conn_help *help;
338
339	if (ct && !nf_ct_is_untracked(ct)) {
340		help = nfct_help(ct);
341		if (help)
342			module_put(help->helper->me);
343
344		nf_ct_netns_put(par->net, par->family);
345
346		xt_ct_destroy_timeout(ct);
347		nf_ct_put(info->ct);
348	}
349}
350
351static void xt_ct_tg_destroy_v0(const struct xt_tgdtor_param *par)
352{
353	struct xt_ct_target_info *info = par->targinfo;
354	struct xt_ct_target_info_v1 info_v1 = {
355		.flags 		= info->flags,
356		.zone		= info->zone,
357		.ct_events	= info->ct_events,
358		.exp_events	= info->exp_events,
359		.ct		= info->ct,
360	};
361	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
362
363	xt_ct_tg_destroy(par, &info_v1);
364}
365
366static void xt_ct_tg_destroy_v1(const struct xt_tgdtor_param *par)
367{
368	xt_ct_tg_destroy(par, par->targinfo);
369}
370
371static struct xt_target xt_ct_tg_reg[] __read_mostly = {
372	{
373		.name		= "CT",
374		.family		= NFPROTO_UNSPEC,
375		.targetsize	= sizeof(struct xt_ct_target_info),
 
376		.checkentry	= xt_ct_tg_check_v0,
377		.destroy	= xt_ct_tg_destroy_v0,
378		.target		= xt_ct_target_v0,
379		.table		= "raw",
380		.me		= THIS_MODULE,
381	},
382	{
383		.name		= "CT",
384		.family		= NFPROTO_UNSPEC,
385		.revision	= 1,
386		.targetsize	= sizeof(struct xt_ct_target_info_v1),
 
387		.checkentry	= xt_ct_tg_check_v1,
388		.destroy	= xt_ct_tg_destroy_v1,
389		.target		= xt_ct_target_v1,
390		.table		= "raw",
391		.me		= THIS_MODULE,
392	},
393	{
394		.name		= "CT",
395		.family		= NFPROTO_UNSPEC,
396		.revision	= 2,
397		.targetsize	= sizeof(struct xt_ct_target_info_v1),
 
398		.checkentry	= xt_ct_tg_check_v2,
399		.destroy	= xt_ct_tg_destroy_v1,
400		.target		= xt_ct_target_v1,
401		.table		= "raw",
402		.me		= THIS_MODULE,
403	},
404};
405
406static unsigned int
407notrack_tg(struct sk_buff *skb, const struct xt_action_param *par)
408{
409	/* Previously seen (loopback)? Ignore. */
410	if (skb->nfct != NULL)
411		return XT_CONTINUE;
412
413	skb->nfct = &nf_ct_untracked_get()->ct_general;
414	skb->nfctinfo = IP_CT_NEW;
415	nf_conntrack_get(skb->nfct);
416
417	return XT_CONTINUE;
418}
419
420static int notrack_chk(const struct xt_tgchk_param *par)
421{
422	if (!par->net->xt.notrack_deprecated_warning) {
423		pr_info("netfilter: NOTRACK target is deprecated, "
424			"use CT instead or upgrade iptables\n");
425		par->net->xt.notrack_deprecated_warning = true;
426	}
427	return 0;
428}
429
430static struct xt_target notrack_tg_reg __read_mostly = {
431	.name		= "NOTRACK",
432	.revision	= 0,
433	.family		= NFPROTO_UNSPEC,
434	.checkentry	= notrack_chk,
435	.target		= notrack_tg,
436	.table		= "raw",
437	.me		= THIS_MODULE,
438};
439
440static int __init xt_ct_tg_init(void)
441{
442	int ret;
443
444	ret = xt_register_target(&notrack_tg_reg);
445	if (ret < 0)
446		return ret;
447
448	ret = xt_register_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
449	if (ret < 0) {
450		xt_unregister_target(&notrack_tg_reg);
451		return ret;
452	}
453	return 0;
454}
455
456static void __exit xt_ct_tg_exit(void)
457{
458	xt_unregister_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
459	xt_unregister_target(&notrack_tg_reg);
460}
461
462module_init(xt_ct_tg_init);
463module_exit(xt_ct_tg_exit);
464
465MODULE_LICENSE("GPL");
466MODULE_DESCRIPTION("Xtables: connection tracking target");
467MODULE_ALIAS("ipt_CT");
468MODULE_ALIAS("ip6t_CT");
469MODULE_ALIAS("ipt_NOTRACK");
470MODULE_ALIAS("ip6t_NOTRACK");
v6.2
  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		refcount_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	rcu_assign_pointer(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 void xt_ct_put_helper(struct nf_conn_help *help)
140{
141	struct nf_conntrack_helper *helper;
142
143	if (!help)
144		return;
145
146	/* not yet exposed to other cpus, or ruleset
147	 * already detached (post-replacement).
148	 */
149	helper = rcu_dereference_raw(help->helper);
150	if (helper)
151		nf_conntrack_helper_put(helper);
152}
153
154static int xt_ct_tg_check(const struct xt_tgchk_param *par,
155			  struct xt_ct_target_info_v1 *info)
156{
157	struct nf_conntrack_zone zone;
158	struct nf_conn_help *help;
159	struct nf_conn *ct;
160	int ret = -EOPNOTSUPP;
161
162	if (info->flags & XT_CT_NOTRACK) {
163		ct = NULL;
164		goto out;
165	}
166
167#ifndef CONFIG_NF_CONNTRACK_ZONES
168	if (info->zone || info->flags & (XT_CT_ZONE_DIR_ORIG |
169					 XT_CT_ZONE_DIR_REPL |
170					 XT_CT_ZONE_MARK))
171		goto err1;
172#endif
173
174	ret = nf_ct_netns_get(par->net, par->family);
175	if (ret < 0)
176		goto err1;
177
178	memset(&zone, 0, sizeof(zone));
179	zone.id = info->zone;
180	zone.dir = xt_ct_flags_to_dir(info);
181	if (info->flags & XT_CT_ZONE_MARK)
182		zone.flags |= NF_CT_FLAG_MARK;
183
184	ct = nf_ct_tmpl_alloc(par->net, &zone, GFP_KERNEL);
185	if (!ct) {
186		ret = -ENOMEM;
187		goto err2;
188	}
189
 
190	if ((info->ct_events || info->exp_events) &&
191	    !nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
192				  GFP_KERNEL)) {
193		ret = -EINVAL;
194		goto err3;
195	}
196
197	if (info->helper[0]) {
198		if (strnlen(info->helper, sizeof(info->helper)) == sizeof(info->helper)) {
199			ret = -ENAMETOOLONG;
200			goto err3;
201		}
202
203		ret = xt_ct_set_helper(ct, info->helper, par);
204		if (ret < 0)
205			goto err3;
206	}
207
208	if (info->timeout[0]) {
209		if (strnlen(info->timeout, sizeof(info->timeout)) == sizeof(info->timeout)) {
210			ret = -ENAMETOOLONG;
211			goto err4;
212		}
213
214		ret = xt_ct_set_timeout(ct, par, info->timeout);
215		if (ret < 0)
216			goto err4;
217	}
218	__set_bit(IPS_CONFIRMED_BIT, &ct->status);
 
219out:
220	info->ct = ct;
221	return 0;
222
223err4:
224	help = nfct_help(ct);
225	xt_ct_put_helper(help);
226err3:
227	nf_ct_tmpl_free(ct);
228err2:
229	nf_ct_netns_put(par->net, par->family);
230err1:
231	return ret;
232}
233
234static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
235{
236	struct xt_ct_target_info *info = par->targinfo;
237	struct xt_ct_target_info_v1 info_v1 = {
238		.flags 		= info->flags,
239		.zone		= info->zone,
240		.ct_events	= info->ct_events,
241		.exp_events	= info->exp_events,
242	};
243	int ret;
244
245	if (info->flags & ~XT_CT_NOTRACK)
246		return -EINVAL;
247
248	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
249
250	ret = xt_ct_tg_check(par, &info_v1);
251	if (ret < 0)
252		return ret;
253
254	info->ct = info_v1.ct;
255
256	return ret;
257}
258
259static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
260{
261	struct xt_ct_target_info_v1 *info = par->targinfo;
262
263	if (info->flags & ~XT_CT_NOTRACK)
264		return -EINVAL;
265
266	return xt_ct_tg_check(par, par->targinfo);
267}
268
269static int xt_ct_tg_check_v2(const struct xt_tgchk_param *par)
270{
271	struct xt_ct_target_info_v1 *info = par->targinfo;
272
273	if (info->flags & ~XT_CT_MASK)
274		return -EINVAL;
275
276	return xt_ct_tg_check(par, par->targinfo);
277}
278
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
279static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
280			     struct xt_ct_target_info_v1 *info)
281{
282	struct nf_conn *ct = info->ct;
283	struct nf_conn_help *help;
284
285	if (ct) {
286		help = nfct_help(ct);
287		xt_ct_put_helper(help);
 
288
289		nf_ct_netns_put(par->net, par->family);
290
291		nf_ct_destroy_timeout(ct);
292		nf_ct_put(info->ct);
293	}
294}
295
296static void xt_ct_tg_destroy_v0(const struct xt_tgdtor_param *par)
297{
298	struct xt_ct_target_info *info = par->targinfo;
299	struct xt_ct_target_info_v1 info_v1 = {
300		.flags 		= info->flags,
301		.zone		= info->zone,
302		.ct_events	= info->ct_events,
303		.exp_events	= info->exp_events,
304		.ct		= info->ct,
305	};
306	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
307
308	xt_ct_tg_destroy(par, &info_v1);
309}
310
311static void xt_ct_tg_destroy_v1(const struct xt_tgdtor_param *par)
312{
313	xt_ct_tg_destroy(par, par->targinfo);
314}
315
316static struct xt_target xt_ct_tg_reg[] __read_mostly = {
317	{
318		.name		= "CT",
319		.family		= NFPROTO_UNSPEC,
320		.targetsize	= sizeof(struct xt_ct_target_info),
321		.usersize	= offsetof(struct xt_ct_target_info, ct),
322		.checkentry	= xt_ct_tg_check_v0,
323		.destroy	= xt_ct_tg_destroy_v0,
324		.target		= xt_ct_target_v0,
325		.table		= "raw",
326		.me		= THIS_MODULE,
327	},
328	{
329		.name		= "CT",
330		.family		= NFPROTO_UNSPEC,
331		.revision	= 1,
332		.targetsize	= sizeof(struct xt_ct_target_info_v1),
333		.usersize	= offsetof(struct xt_ct_target_info, ct),
334		.checkentry	= xt_ct_tg_check_v1,
335		.destroy	= xt_ct_tg_destroy_v1,
336		.target		= xt_ct_target_v1,
337		.table		= "raw",
338		.me		= THIS_MODULE,
339	},
340	{
341		.name		= "CT",
342		.family		= NFPROTO_UNSPEC,
343		.revision	= 2,
344		.targetsize	= sizeof(struct xt_ct_target_info_v1),
345		.usersize	= offsetof(struct xt_ct_target_info, ct),
346		.checkentry	= xt_ct_tg_check_v2,
347		.destroy	= xt_ct_tg_destroy_v1,
348		.target		= xt_ct_target_v1,
349		.table		= "raw",
350		.me		= THIS_MODULE,
351	},
352};
353
354static unsigned int
355notrack_tg(struct sk_buff *skb, const struct xt_action_param *par)
356{
357	/* Previously seen (loopback)? Ignore. */
358	if (skb->_nfct != 0)
359		return XT_CONTINUE;
360
361	nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
 
 
362
363	return XT_CONTINUE;
364}
365
 
 
 
 
 
 
 
 
 
 
366static struct xt_target notrack_tg_reg __read_mostly = {
367	.name		= "NOTRACK",
368	.revision	= 0,
369	.family		= NFPROTO_UNSPEC,
 
370	.target		= notrack_tg,
371	.table		= "raw",
372	.me		= THIS_MODULE,
373};
374
375static int __init xt_ct_tg_init(void)
376{
377	int ret;
378
379	ret = xt_register_target(&notrack_tg_reg);
380	if (ret < 0)
381		return ret;
382
383	ret = xt_register_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
384	if (ret < 0) {
385		xt_unregister_target(&notrack_tg_reg);
386		return ret;
387	}
388	return 0;
389}
390
391static void __exit xt_ct_tg_exit(void)
392{
393	xt_unregister_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
394	xt_unregister_target(&notrack_tg_reg);
395}
396
397module_init(xt_ct_tg_init);
398module_exit(xt_ct_tg_exit);
399
400MODULE_LICENSE("GPL");
401MODULE_DESCRIPTION("Xtables: connection tracking target");
402MODULE_ALIAS("ipt_CT");
403MODULE_ALIAS("ip6t_CT");
404MODULE_ALIAS("ipt_NOTRACK");
405MODULE_ALIAS("ip6t_NOTRACK");