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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");
v3.5.6
  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 unsigned int xt_ct_target_v0(struct sk_buff *skb,
 24				    const struct xt_action_param *par)
 25{
 26	const struct xt_ct_target_info *info = par->targinfo;
 27	struct nf_conn *ct = info->ct;
 28
 29	/* Previously seen (loopback)? Ignore. */
 30	if (skb->nfct != NULL)
 31		return XT_CONTINUE;
 32
 
 
 
 33	atomic_inc(&ct->ct_general.use);
 34	skb->nfct = &ct->ct_general;
 35	skb->nfctinfo = IP_CT_NEW;
 36
 37	return XT_CONTINUE;
 38}
 39
 
 
 
 
 
 
 
 
 
 40static unsigned int xt_ct_target_v1(struct sk_buff *skb,
 41				    const struct xt_action_param *par)
 42{
 43	const struct xt_ct_target_info_v1 *info = par->targinfo;
 44	struct nf_conn *ct = info->ct;
 45
 46	/* Previously seen (loopback)? Ignore. */
 47	if (skb->nfct != NULL)
 48		return XT_CONTINUE;
 49
 50	atomic_inc(&ct->ct_general.use);
 51	skb->nfct = &ct->ct_general;
 52	skb->nfctinfo = IP_CT_NEW;
 53
 54	return XT_CONTINUE;
 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 xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
 
 
 76{
 77	struct xt_ct_target_info *info = par->targinfo;
 78	struct nf_conntrack_tuple t;
 79	struct nf_conn_help *help;
 80	struct nf_conn *ct;
 81	int ret = 0;
 82	u8 proto;
 83
 84	if (info->flags & ~XT_CT_NOTRACK)
 85		return -EINVAL;
 
 
 
 
 86
 87	if (info->flags & XT_CT_NOTRACK) {
 88		ct = nf_ct_untracked_get();
 89		atomic_inc(&ct->ct_general.use);
 90		goto out;
 
 91	}
 92
 93#ifndef CONFIG_NF_CONNTRACK_ZONES
 94	if (info->zone)
 95		goto err1;
 96#endif
 97
 98	ret = nf_ct_l3proto_try_module_get(par->family);
 99	if (ret < 0)
100		goto err1;
101
102	memset(&t, 0, sizeof(t));
103	ct = nf_conntrack_alloc(par->net, info->zone, &t, &t, GFP_KERNEL);
104	ret = PTR_ERR(ct);
105	if (IS_ERR(ct))
106		goto err2;
107
108	ret = 0;
109	if ((info->ct_events || info->exp_events) &&
110	    !nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
111				  GFP_KERNEL))
112		goto err3;
113
114	if (info->helper[0]) {
115		ret = -ENOENT;
116		proto = xt_ct_find_proto(par);
117		if (!proto) {
118			pr_info("You must specify a L4 protocol, "
119				"and not use inversions on it.\n");
120			goto err3;
121		}
122
123		ret = -ENOMEM;
124		help = nf_ct_helper_ext_add(ct, GFP_KERNEL);
125		if (help == NULL)
126			goto err3;
127
128		ret = -ENOENT;
129		help->helper = nf_conntrack_helper_try_module_get(info->helper,
130								  par->family,
131								  proto);
132		if (help->helper == NULL) {
133			pr_info("No such helper \"%s\"\n", info->helper);
134			goto err3;
135		}
136	}
137
138	__set_bit(IPS_TEMPLATE_BIT, &ct->status);
139	__set_bit(IPS_CONFIRMED_BIT, &ct->status);
140out:
141	info->ct = ct;
142	return 0;
143
144err3:
145	nf_conntrack_free(ct);
146err2:
147	nf_ct_l3proto_module_put(par->family);
148err1:
149	return ret;
150}
151
152#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
153static void __xt_ct_tg_timeout_put(struct ctnl_timeout *timeout)
154{
155	typeof(nf_ct_timeout_put_hook) timeout_put;
156
157	timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
158	if (timeout_put)
159		timeout_put(timeout);
160}
161#endif
162
163static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
 
 
164{
165	struct xt_ct_target_info_v1 *info = par->targinfo;
166	struct nf_conntrack_tuple t;
167	struct nf_conn_help *help;
168	struct nf_conn *ct;
 
169	int ret = 0;
170	u8 proto;
171#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
172	struct ctnl_timeout *timeout;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
173#endif
174	if (info->flags & ~XT_CT_NOTRACK)
175		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
176
177	if (info->flags & XT_CT_NOTRACK) {
178		ct = nf_ct_untracked_get();
179		atomic_inc(&ct->ct_general.use);
180		goto out;
181	}
182
183#ifndef CONFIG_NF_CONNTRACK_ZONES
184	if (info->zone)
 
 
185		goto err1;
186#endif
187
188	ret = nf_ct_l3proto_try_module_get(par->family);
189	if (ret < 0)
190		goto err1;
191
192	memset(&t, 0, sizeof(t));
193	ct = nf_conntrack_alloc(par->net, info->zone, &t, &t, GFP_KERNEL);
194	ret = PTR_ERR(ct);
195	if (IS_ERR(ct))
 
 
 
 
 
196		goto err2;
 
197
198	ret = 0;
199	if ((info->ct_events || info->exp_events) &&
200	    !nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
201				  GFP_KERNEL))
 
202		goto err3;
 
203
204	if (info->helper[0]) {
205		ret = -ENOENT;
206		proto = xt_ct_find_proto(par);
207		if (!proto) {
208			pr_info("You must specify a L4 protocol, "
209				"and not use inversions on it.\n");
210			goto err3;
211		}
212
213		ret = -ENOMEM;
214		help = nf_ct_helper_ext_add(ct, GFP_KERNEL);
215		if (help == NULL)
216			goto err3;
217
218		ret = -ENOENT;
219		help->helper = nf_conntrack_helper_try_module_get(info->helper,
220								  par->family,
221								  proto);
222		if (help->helper == NULL) {
223			pr_info("No such helper \"%s\"\n", info->helper);
224			goto err3;
225		}
226	}
227
228#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
229	if (info->timeout[0]) {
230		typeof(nf_ct_timeout_find_get_hook) timeout_find_get;
231		struct nf_conn_timeout *timeout_ext;
232
233		rcu_read_lock();
234		timeout_find_get =
235			rcu_dereference(nf_ct_timeout_find_get_hook);
236
237		if (timeout_find_get) {
238			const struct ipt_entry *e = par->entryinfo;
239			struct nf_conntrack_l4proto *l4proto;
240
241			if (e->ip.invflags & IPT_INV_PROTO) {
242				ret = -EINVAL;
243				pr_info("You cannot use inversion on "
244					 "L4 protocol\n");
245				goto err4;
246			}
247			timeout = timeout_find_get(info->timeout);
248			if (timeout == NULL) {
249				ret = -ENOENT;
250				pr_info("No such timeout policy \"%s\"\n",
251					info->timeout);
252				goto err4;
253			}
254			if (timeout->l3num != par->family) {
255				ret = -EINVAL;
256				pr_info("Timeout policy `%s' can only be "
257					"used by L3 protocol number %d\n",
258					info->timeout, timeout->l3num);
259				goto err5;
260			}
261			/* Make sure the timeout policy matches any existing
262			 * protocol tracker, otherwise default to generic.
263			 */
264			l4proto = __nf_ct_l4proto_find(par->family,
265						       e->ip.proto);
266			if (timeout->l4proto->l4proto != l4proto->l4proto) {
267				ret = -EINVAL;
268				pr_info("Timeout policy `%s' can only be "
269					"used by L4 protocol number %d\n",
270					info->timeout,
271					timeout->l4proto->l4proto);
272				goto err5;
273			}
274			timeout_ext = nf_ct_timeout_ext_add(ct, timeout,
275							    GFP_ATOMIC);
276			if (timeout_ext == NULL) {
277				ret = -ENOMEM;
278				goto err5;
279			}
280		} else {
281			ret = -ENOENT;
282			pr_info("Timeout policy base is empty\n");
283			goto err4;
284		}
285		rcu_read_unlock();
286	}
287#endif
288
289	__set_bit(IPS_TEMPLATE_BIT, &ct->status);
290	__set_bit(IPS_CONFIRMED_BIT, &ct->status);
 
291out:
292	info->ct = ct;
293	return 0;
294
295#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
296err5:
297	__xt_ct_tg_timeout_put(timeout);
298err4:
299	rcu_read_unlock();
300#endif
301err3:
302	nf_conntrack_free(ct);
303err2:
304	nf_ct_l3proto_module_put(par->family);
305err1:
306	return ret;
307}
308
309static void xt_ct_tg_destroy_v0(const struct xt_tgdtor_param *par)
310{
311	struct xt_ct_target_info *info = par->targinfo;
312	struct nf_conn *ct = info->ct;
313	struct nf_conn_help *help;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
314
315	if (!nf_ct_is_untracked(ct)) {
316		help = nfct_help(ct);
317		if (help)
318			module_put(help->helper->me);
319
320		nf_ct_l3proto_module_put(par->family);
321	}
322	nf_ct_put(info->ct);
323}
324
325static void xt_ct_tg_destroy_v1(const struct xt_tgdtor_param *par)
326{
327	struct xt_ct_target_info_v1 *info = par->targinfo;
328	struct nf_conn *ct = info->ct;
329	struct nf_conn_help *help;
 
 
 
 
 
 
 
330#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
331	struct nf_conn_timeout *timeout_ext;
332	typeof(nf_ct_timeout_put_hook) timeout_put;
 
 
 
 
 
 
 
 
 
 
 
 
333#endif
334	if (!nf_ct_is_untracked(ct)) {
 
 
 
 
 
 
 
 
335		help = nfct_help(ct);
336		if (help)
337			module_put(help->helper->me);
338
339		nf_ct_l3proto_module_put(par->family);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
340
341#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
342		rcu_read_lock();
343		timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
344
345		if (timeout_put) {
346			timeout_ext = nf_ct_timeout_find(ct);
347			if (timeout_ext)
348				timeout_put(timeout_ext->timeout);
349		}
350		rcu_read_unlock();
351#endif
352	}
353	nf_ct_put(info->ct);
354}
355
356static struct xt_target xt_ct_tg_reg[] __read_mostly = {
357	{
358		.name		= "CT",
359		.family		= NFPROTO_UNSPEC,
360		.targetsize	= sizeof(struct xt_ct_target_info),
361		.checkentry	= xt_ct_tg_check_v0,
362		.destroy	= xt_ct_tg_destroy_v0,
363		.target		= xt_ct_target_v0,
364		.table		= "raw",
365		.me		= THIS_MODULE,
366	},
367	{
368		.name		= "CT",
369		.family		= NFPROTO_UNSPEC,
370		.revision	= 1,
371		.targetsize	= sizeof(struct xt_ct_target_info_v1),
372		.checkentry	= xt_ct_tg_check_v1,
373		.destroy	= xt_ct_tg_destroy_v1,
374		.target		= xt_ct_target_v1,
375		.table		= "raw",
376		.me		= THIS_MODULE,
377	},
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
378};
379
380static int __init xt_ct_tg_init(void)
381{
382	return xt_register_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
 
 
 
 
 
 
 
 
 
 
 
383}
384
385static void __exit xt_ct_tg_exit(void)
386{
387	xt_unregister_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
 
388}
389
390module_init(xt_ct_tg_init);
391module_exit(xt_ct_tg_exit);
392
393MODULE_LICENSE("GPL");
394MODULE_DESCRIPTION("Xtables: connection tracking target");
395MODULE_ALIAS("ipt_CT");
396MODULE_ALIAS("ip6t_CT");