[deliverable/linux.git] / net / netfilter / nf_conntrack_proto.c

/* L3/L4 protocol support for nf_conntrack. */

/* (C) 1999-2001 Paul `Rusty' Russell
 * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
 * (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org>
 *
 * 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.
 */

#include <linux/types.h>
#include <linux/netfilter.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/skbuff.h>
#include <linux/vmalloc.h>
#include <linux/stddef.h>
#include <linux/err.h>
#include <linux/percpu.h>
#include <linux/moduleparam.h>
#include <linux/notifier.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>

#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_l3proto.h>
#include <net/netfilter/nf_conntrack_l4proto.h>
#include <net/netfilter/nf_conntrack_core.h>

static struct nf_conntrack_l4proto **nf_ct_protos[PF_MAX] __read_mostly;
struct nf_conntrack_l3proto *nf_ct_l3protos[AF_MAX] __read_mostly;
EXPORT_SYMBOL_GPL(nf_ct_l3protos);

static DEFINE_MUTEX(nf_ct_proto_mutex);

#ifdef CONFIG_SYSCTL
static int
nf_ct_register_sysctl(struct ctl_table_header **header, struct ctl_path *path,
		      struct ctl_table *table, unsigned int *users)
{
	if (*header == NULL) {
		*header = register_sysctl_paths(path, table);
		if (*header == NULL)
			return -ENOMEM;
	}
	if (users != NULL)
		(*users)++;
	return 0;
}

static void
nf_ct_unregister_sysctl(struct ctl_table_header **header,
			struct ctl_table *table, unsigned int *users)
{
	if (users != NULL && --*users > 0)
		return;

	unregister_sysctl_table(*header);
	*header = NULL;
}
#endif

struct nf_conntrack_l4proto *
__nf_ct_l4proto_find(u_int16_t l3proto, u_int8_t l4proto)
{
	if (unlikely(l3proto >= AF_MAX || nf_ct_protos[l3proto] == NULL))
		return &nf_conntrack_l4proto_generic;

	return rcu_dereference(nf_ct_protos[l3proto][l4proto]);
}
EXPORT_SYMBOL_GPL(__nf_ct_l4proto_find);

/* this is guaranteed to always return a valid protocol helper, since
 * it falls back to generic_protocol */
struct nf_conntrack_l4proto *
nf_ct_l4proto_find_get(u_int16_t l3proto, u_int8_t l4proto)
{
	struct nf_conntrack_l4proto *p;

	rcu_read_lock();
	p = __nf_ct_l4proto_find(l3proto, l4proto);
	if (!try_module_get(p->me))
		p = &nf_conntrack_l4proto_generic;
	rcu_read_unlock();

	return p;
}
EXPORT_SYMBOL_GPL(nf_ct_l4proto_find_get);

void nf_ct_l4proto_put(struct nf_conntrack_l4proto *p)
{
	module_put(p->me);
}
EXPORT_SYMBOL_GPL(nf_ct_l4proto_put);

struct nf_conntrack_l3proto *
nf_ct_l3proto_find_get(u_int16_t l3proto)
{
	struct nf_conntrack_l3proto *p;

	rcu_read_lock();
	p = __nf_ct_l3proto_find(l3proto);
	if (!try_module_get(p->me))
		p = &nf_conntrack_l3proto_generic;
	rcu_read_unlock();

	return p;
}
EXPORT_SYMBOL_GPL(nf_ct_l3proto_find_get);

void nf_ct_l3proto_put(struct nf_conntrack_l3proto *p)
{
	module_put(p->me);
}
EXPORT_SYMBOL_GPL(nf_ct_l3proto_put);

int
nf_ct_l3proto_try_module_get(unsigned short l3proto)
{
	int ret;
	struct nf_conntrack_l3proto *p;

retry:	p = nf_ct_l3proto_find_get(l3proto);
	if (p == &nf_conntrack_l3proto_generic) {
		ret = request_module("nf_conntrack-%d", l3proto);
		if (!ret)
			goto retry;

		return -EPROTOTYPE;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(nf_ct_l3proto_try_module_get);

void nf_ct_l3proto_module_put(unsigned short l3proto)
{
	struct nf_conntrack_l3proto *p;

	/* rcu_read_lock not necessary since the caller holds a reference */
	p = __nf_ct_l3proto_find(l3proto);
	module_put(p->me);
}
EXPORT_SYMBOL_GPL(nf_ct_l3proto_module_put);

static int kill_l3proto(struct nf_conn *i, void *data)
{
	return nf_ct_l3num(i) == ((struct nf_conntrack_l3proto *)data)->l3proto;
}

static int kill_l4proto(struct nf_conn *i, void *data)
{
	struct nf_conntrack_l4proto *l4proto;
	l4proto = (struct nf_conntrack_l4proto *)data;
	return nf_ct_protonum(i) == l4proto->l4proto &&
	       nf_ct_l3num(i) == l4proto->l3proto;
}

static int nf_ct_l3proto_register_sysctl(struct nf_conntrack_l3proto *l3proto)
{
	int err = 0;

#ifdef CONFIG_SYSCTL
	if (l3proto->ctl_table != NULL) {
		err = nf_ct_register_sysctl(&l3proto->ctl_table_header,
					    l3proto->ctl_table_path,
					    l3proto->ctl_table, NULL);
	}
#endif
	return err;
}

static void nf_ct_l3proto_unregister_sysctl(struct nf_conntrack_l3proto *l3proto)
{
#ifdef CONFIG_SYSCTL
	if (l3proto->ctl_table_header != NULL)
		nf_ct_unregister_sysctl(&l3proto->ctl_table_header,
					l3proto->ctl_table, NULL);
#endif
}

int nf_conntrack_l3proto_register(struct nf_conntrack_l3proto *proto)
{
	int ret = 0;

	if (proto->l3proto >= AF_MAX)
		return -EBUSY;

	mutex_lock(&nf_ct_proto_mutex);
	if (nf_ct_l3protos[proto->l3proto] != &nf_conntrack_l3proto_generic) {
		ret = -EBUSY;
		goto out_unlock;
	}

	ret = nf_ct_l3proto_register_sysctl(proto);
	if (ret < 0)
		goto out_unlock;

	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto], proto);

out_unlock:
	mutex_unlock(&nf_ct_proto_mutex);
	return ret;
}
EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_register);

void nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto)
{
	struct net *net;

	BUG_ON(proto->l3proto >= AF_MAX);

	mutex_lock(&nf_ct_proto_mutex);
	BUG_ON(nf_ct_l3protos[proto->l3proto] != proto);
	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto],
			   &nf_conntrack_l3proto_generic);
	nf_ct_l3proto_unregister_sysctl(proto);
	mutex_unlock(&nf_ct_proto_mutex);

	synchronize_rcu();

	/* Remove all contrack entries for this protocol */
	for_each_net(net)
		nf_ct_iterate_cleanup(net, kill_l3proto, proto);
}
EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_unregister);

static int nf_ct_l4proto_register_sysctl(struct nf_conntrack_l4proto *l4proto)
{
	int err = 0;

#ifdef CONFIG_SYSCTL
	if (l4proto->ctl_table != NULL) {
		err = nf_ct_register_sysctl(l4proto->ctl_table_header,
					    nf_net_netfilter_sysctl_path,
					    l4proto->ctl_table,
					    l4proto->ctl_table_users);
		if (err < 0)
			goto out;
	}
#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
	if (l4proto->ctl_compat_table != NULL) {
		err = nf_ct_register_sysctl(&l4proto->ctl_compat_table_header,
					    nf_net_ipv4_netfilter_sysctl_path,
					    l4proto->ctl_compat_table, NULL);
		if (err == 0)
			goto out;
		nf_ct_unregister_sysctl(l4proto->ctl_table_header,
					l4proto->ctl_table,
					l4proto->ctl_table_users);
	}
#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
out:
#endif /* CONFIG_SYSCTL */
	return err;
}

static void nf_ct_l4proto_unregister_sysctl(struct nf_conntrack_l4proto *l4proto)
{
#ifdef CONFIG_SYSCTL
	if (l4proto->ctl_table_header != NULL &&
	    *l4proto->ctl_table_header != NULL)
		nf_ct_unregister_sysctl(l4proto->ctl_table_header,
					l4proto->ctl_table,
					l4proto->ctl_table_users);
#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
	if (l4proto->ctl_compat_table_header != NULL)
		nf_ct_unregister_sysctl(&l4proto->ctl_compat_table_header,
					l4proto->ctl_compat_table, NULL);
#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
#endif /* CONFIG_SYSCTL */
}

/* FIXME: Allow NULL functions and sub in pointers to generic for
   them. --RR */
int nf_conntrack_l4proto_register(struct nf_conntrack_l4proto *l4proto)
{
	int ret = 0;

	if (l4proto->l3proto >= PF_MAX)
		return -EBUSY;

	mutex_lock(&nf_ct_proto_mutex);
	if (!nf_ct_protos[l4proto->l3proto]) {
		/* l3proto may be loaded latter. */
		struct nf_conntrack_l4proto **proto_array;
		int i;

		proto_array = kmalloc(MAX_NF_CT_PROTO *
				      sizeof(struct nf_conntrack_l4proto *),
				      GFP_KERNEL);
		if (proto_array == NULL) {
			ret = -ENOMEM;
			goto out_unlock;
		}

		for (i = 0; i < MAX_NF_CT_PROTO; i++)
			proto_array[i] = &nf_conntrack_l4proto_generic;
		nf_ct_protos[l4proto->l3proto] = proto_array;
	} else if (nf_ct_protos[l4proto->l3proto][l4proto->l4proto] !=
					&nf_conntrack_l4proto_generic) {
		ret = -EBUSY;
		goto out_unlock;
	}

	ret = nf_ct_l4proto_register_sysctl(l4proto);
	if (ret < 0)
		goto out_unlock;

	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
			   l4proto);

out_unlock:
	mutex_unlock(&nf_ct_proto_mutex);
	return ret;
}
EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_register);

void nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
{
	struct net *net;

	BUG_ON(l4proto->l3proto >= PF_MAX);

	mutex_lock(&nf_ct_proto_mutex);
	BUG_ON(nf_ct_protos[l4proto->l3proto][l4proto->l4proto] != l4proto);
	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
			   &nf_conntrack_l4proto_generic);
	nf_ct_l4proto_unregister_sysctl(l4proto);
	mutex_unlock(&nf_ct_proto_mutex);

	synchronize_rcu();

	/* Remove all contrack entries for this protocol */
	for_each_net(net)
		nf_ct_iterate_cleanup(net, kill_l4proto, l4proto);
}
EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_unregister);

int nf_conntrack_proto_init(void)
{
	unsigned int i;
	int err;

	err = nf_ct_l4proto_register_sysctl(&nf_conntrack_l4proto_generic);
	if (err < 0)
		return err;

	for (i = 0; i < AF_MAX; i++)
		rcu_assign_pointer(nf_ct_l3protos[i],
				   &nf_conntrack_l3proto_generic);
	return 0;
}

void nf_conntrack_proto_fini(void)
{
	unsigned int i;

	nf_ct_l4proto_unregister_sysctl(&nf_conntrack_l4proto_generic);

	/* free l3proto protocol tables */
	for (i = 0; i < PF_MAX; i++)
		kfree(nf_ct_protos[i]);
}
Commit	Line	Data
8f03dea5 MJ	1	/* L3/L4 protocol support for nf_conntrack. */
	2
	3	/* (C) 1999-2001 Paul `Rusty' Russell
	4	* (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
	5	* (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*/
	11
	12	#include <linux/types.h>
	13	#include <linux/netfilter.h>
	14	#include <linux/module.h>
d62f9ed4	15	#include <linux/mutex.h>
8f03dea5 MJ	16	#include <linux/skbuff.h>
	17	#include <linux/vmalloc.h>
	18	#include <linux/stddef.h>
	19	#include <linux/err.h>
	20	#include <linux/percpu.h>
	21	#include <linux/moduleparam.h>
	22	#include <linux/notifier.h>
	23	#include <linux/kernel.h>
	24	#include <linux/netdevice.h>
	25
	26	#include <net/netfilter/nf_conntrack.h>
	27	#include <net/netfilter/nf_conntrack_l3proto.h>
605dcad6	28	#include <net/netfilter/nf_conntrack_l4proto.h>
8f03dea5 MJ	29	#include <net/netfilter/nf_conntrack_core.h>
8f03dea5 MJ	30
42bad1da	31	static struct nf_conntrack_l4proto **nf_ct_protos[PF_MAX] __read_mostly;
ae5718fb	32	struct nf_conntrack_l3proto *nf_ct_l3protos[AF_MAX] __read_mostly;
13b18339	33	EXPORT_SYMBOL_GPL(nf_ct_l3protos);
8f03dea5	34
b19caa0c	35	static DEFINE_MUTEX(nf_ct_proto_mutex);
d62f9ed4	36
b19caa0c	37	#ifdef CONFIG_SYSCTL
d62f9ed4	38	static int
b3fd3ffe	39	nf_ct_register_sysctl(struct ctl_table_header *header, struct ctl_path path,
d62f9ed4 PM	40	struct ctl_table table, unsigned int users)
	41	{
	42	if (*header == NULL) {
b3fd3ffe	43	*header = register_sysctl_paths(path, table);
d62f9ed4 PM	44	if (*header == NULL)
	45	return -ENOMEM;
	46	}
	47	if (users != NULL)
	48	(*users)++;
	49	return 0;
	50	}
	51
	52	static void
	53	nf_ct_unregister_sysctl(struct ctl_table_header **header,
	54	struct ctl_table table, unsigned int users)
	55	{
	56	if (users != NULL && --*users > 0)
	57	return;
b3fd3ffe PE	58
b3fd3ffe PE	59	unregister_sysctl_table(*header);
d62f9ed4 PM	60	*header = NULL;
	61	}
	62	#endif
	63
605dcad6 MJ	64	struct nf_conntrack_l4proto *
605dcad6 MJ	65	__nf_ct_l4proto_find(u_int16_t l3proto, u_int8_t l4proto)
8f03dea5 MJ	66	{
8f03dea5 MJ	67	if (unlikely(l3proto >= AF_MAX \|\| nf_ct_protos[l3proto] == NULL))
605dcad6	68	return &nf_conntrack_l4proto_generic;
8f03dea5	69
923f4902	70	return rcu_dereference(nf_ct_protos[l3proto][l4proto]);
8f03dea5	71	}
13b18339	72	EXPORT_SYMBOL_GPL(__nf_ct_l4proto_find);
8f03dea5 MJ	73
	74	/* this is guaranteed to always return a valid protocol helper, since
	75	* it falls back to generic_protocol */
605dcad6 MJ	76	struct nf_conntrack_l4proto *
605dcad6 MJ	77	nf_ct_l4proto_find_get(u_int16_t l3proto, u_int8_t l4proto)
8f03dea5	78	{
605dcad6	79	struct nf_conntrack_l4proto *p;
8f03dea5	80
923f4902	81	rcu_read_lock();
605dcad6	82	p = __nf_ct_l4proto_find(l3proto, l4proto);
8f03dea5	83	if (!try_module_get(p->me))
605dcad6	84	p = &nf_conntrack_l4proto_generic;
923f4902	85	rcu_read_unlock();
8f03dea5 MJ	86
	87	return p;
	88	}
13b18339	89	EXPORT_SYMBOL_GPL(nf_ct_l4proto_find_get);
8f03dea5	90
605dcad6	91	void nf_ct_l4proto_put(struct nf_conntrack_l4proto *p)
8f03dea5 MJ	92	{
	93	module_put(p->me);
	94	}
13b18339	95	EXPORT_SYMBOL_GPL(nf_ct_l4proto_put);
8f03dea5 MJ	96
	97	struct nf_conntrack_l3proto *
	98	nf_ct_l3proto_find_get(u_int16_t l3proto)
	99	{
	100	struct nf_conntrack_l3proto *p;
	101
923f4902	102	rcu_read_lock();
8f03dea5 MJ	103	p = __nf_ct_l3proto_find(l3proto);
8f03dea5 MJ	104	if (!try_module_get(p->me))
605dcad6	105	p = &nf_conntrack_l3proto_generic;
923f4902	106	rcu_read_unlock();
8f03dea5 MJ	107
	108	return p;
	109	}
13b18339	110	EXPORT_SYMBOL_GPL(nf_ct_l3proto_find_get);
8f03dea5 MJ	111
	112	void nf_ct_l3proto_put(struct nf_conntrack_l3proto *p)
	113	{
	114	module_put(p->me);
	115	}
13b18339	116	EXPORT_SYMBOL_GPL(nf_ct_l3proto_put);
8f03dea5 MJ	117
	118	int
	119	nf_ct_l3proto_try_module_get(unsigned short l3proto)
	120	{
	121	int ret;
	122	struct nf_conntrack_l3proto *p;
	123
	124	retry: p = nf_ct_l3proto_find_get(l3proto);
605dcad6	125	if (p == &nf_conntrack_l3proto_generic) {
8f03dea5 MJ	126	ret = request_module("nf_conntrack-%d", l3proto);
	127	if (!ret)
	128	goto retry;
	129
	130	return -EPROTOTYPE;
	131	}
	132
	133	return 0;
	134	}
13b18339	135	EXPORT_SYMBOL_GPL(nf_ct_l3proto_try_module_get);
8f03dea5 MJ	136
	137	void nf_ct_l3proto_module_put(unsigned short l3proto)
	138	{
	139	struct nf_conntrack_l3proto *p;
	140
923f4902	141	/* rcu_read_lock not necessary since the caller holds a reference */
8f03dea5	142	p = __nf_ct_l3proto_find(l3proto);
8f03dea5 MJ	143	module_put(p->me);
8f03dea5 MJ	144	}
13b18339	145	EXPORT_SYMBOL_GPL(nf_ct_l3proto_module_put);
8f03dea5 MJ	146
	147	static int kill_l3proto(struct nf_conn i, void data)
	148	{
5e8fbe2a	149	return nf_ct_l3num(i) == ((struct nf_conntrack_l3proto *)data)->l3proto;
8f03dea5 MJ	150	}
8f03dea5 MJ	151
605dcad6	152	static int kill_l4proto(struct nf_conn i, void data)
8f03dea5	153	{
605dcad6 MJ	154	struct nf_conntrack_l4proto *l4proto;
605dcad6 MJ	155	l4proto = (struct nf_conntrack_l4proto *)data;
5e8fbe2a PM	156	return nf_ct_protonum(i) == l4proto->l4proto &&
5e8fbe2a PM	157	nf_ct_l3num(i) == l4proto->l3proto;
8f03dea5 MJ	158	}
8f03dea5 MJ	159
d62f9ed4 PM	160	static int nf_ct_l3proto_register_sysctl(struct nf_conntrack_l3proto *l3proto)
	161	{
	162	int err = 0;
	163
	164	#ifdef CONFIG_SYSCTL
d62f9ed4 PM	165	if (l3proto->ctl_table != NULL) {
	166	err = nf_ct_register_sysctl(&l3proto->ctl_table_header,
	167	l3proto->ctl_table_path,
	168	l3proto->ctl_table, NULL);
	169	}
d62f9ed4 PM	170	#endif
	171	return err;
	172	}
	173
	174	static void nf_ct_l3proto_unregister_sysctl(struct nf_conntrack_l3proto *l3proto)
	175	{
	176	#ifdef CONFIG_SYSCTL
d62f9ed4 PM	177	if (l3proto->ctl_table_header != NULL)
	178	nf_ct_unregister_sysctl(&l3proto->ctl_table_header,
	179	l3proto->ctl_table, NULL);
d62f9ed4 PM	180	#endif
	181	}
	182
8f03dea5 MJ	183	int nf_conntrack_l3proto_register(struct nf_conntrack_l3proto *proto)
	184	{
	185	int ret = 0;
	186
0661cca9 PM	187	if (proto->l3proto >= AF_MAX)
0661cca9 PM	188	return -EBUSY;
ae5718fb	189
b19caa0c	190	mutex_lock(&nf_ct_proto_mutex);
605dcad6	191	if (nf_ct_l3protos[proto->l3proto] != &nf_conntrack_l3proto_generic) {
8f03dea5	192	ret = -EBUSY;
ae5718fb	193	goto out_unlock;
8f03dea5	194	}
d62f9ed4 PM	195
	196	ret = nf_ct_l3proto_register_sysctl(proto);
	197	if (ret < 0)
0661cca9 PM	198	goto out_unlock;
	199
	200	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto], proto);
8f03dea5	201
ae5718fb	202	out_unlock:
b19caa0c	203	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5 MJ	204	return ret;
8f03dea5 MJ	205	}
13b18339	206	EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_register);
8f03dea5	207
fe3eb20c	208	void nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto)
8f03dea5	209	{
678d6675 AD	210	struct net *net;
678d6675 AD	211
fe3eb20c	212	BUG_ON(proto->l3proto >= AF_MAX);
ae5718fb	213
b19caa0c	214	mutex_lock(&nf_ct_proto_mutex);
fe3eb20c	215	BUG_ON(nf_ct_l3protos[proto->l3proto] != proto);
923f4902 PM	216	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto],
923f4902 PM	217	&nf_conntrack_l3proto_generic);
0661cca9	218	nf_ct_l3proto_unregister_sysctl(proto);
b19caa0c	219	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	220
0661cca9	221	synchronize_rcu();
d62f9ed4	222
8f03dea5	223	/* Remove all contrack entries for this protocol */
678d6675 AD	224	for_each_net(net)
678d6675 AD	225	nf_ct_iterate_cleanup(net, kill_l3proto, proto);
8f03dea5	226	}
13b18339	227	EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_unregister);
8f03dea5	228
d62f9ed4 PM	229	static int nf_ct_l4proto_register_sysctl(struct nf_conntrack_l4proto *l4proto)
	230	{
	231	int err = 0;
	232
	233	#ifdef CONFIG_SYSCTL
d62f9ed4 PM	234	if (l4proto->ctl_table != NULL) {
	235	err = nf_ct_register_sysctl(l4proto->ctl_table_header,
	236	nf_net_netfilter_sysctl_path,
	237	l4proto->ctl_table,
	238	l4proto->ctl_table_users);
a999e683 PM	239	if (err < 0)
a999e683 PM	240	goto out;
d62f9ed4	241	}
a999e683 PM	242	#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
	243	if (l4proto->ctl_compat_table != NULL) {
	244	err = nf_ct_register_sysctl(&l4proto->ctl_compat_table_header,
	245	nf_net_ipv4_netfilter_sysctl_path,
	246	l4proto->ctl_compat_table, NULL);
	247	if (err == 0)
	248	goto out;
	249	nf_ct_unregister_sysctl(l4proto->ctl_table_header,
	250	l4proto->ctl_table,
	251	l4proto->ctl_table_users);
	252	}
	253	#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
	254	out:
933a41e7	255	#endif /* CONFIG_SYSCTL */
d62f9ed4 PM	256	return err;
	257	}
	258
	259	static void nf_ct_l4proto_unregister_sysctl(struct nf_conntrack_l4proto *l4proto)
	260	{
	261	#ifdef CONFIG_SYSCTL
d62f9ed4 PM	262	if (l4proto->ctl_table_header != NULL &&
	263	*l4proto->ctl_table_header != NULL)
	264	nf_ct_unregister_sysctl(l4proto->ctl_table_header,
	265	l4proto->ctl_table,
	266	l4proto->ctl_table_users);
a999e683 PM	267	#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
	268	if (l4proto->ctl_compat_table_header != NULL)
	269	nf_ct_unregister_sysctl(&l4proto->ctl_compat_table_header,
	270	l4proto->ctl_compat_table, NULL);
	271	#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
933a41e7	272	#endif /* CONFIG_SYSCTL */
d62f9ed4 PM	273	}
d62f9ed4 PM	274
8f03dea5 MJ	275	/* FIXME: Allow NULL functions and sub in pointers to generic for
8f03dea5 MJ	276	them. --RR */
605dcad6	277	int nf_conntrack_l4proto_register(struct nf_conntrack_l4proto *l4proto)
8f03dea5 MJ	278	{
	279	int ret = 0;
	280
0661cca9 PM	281	if (l4proto->l3proto >= PF_MAX)
0661cca9 PM	282	return -EBUSY;
ae5718fb	283
b19caa0c	284	mutex_lock(&nf_ct_proto_mutex);
c6a1e615	285	if (!nf_ct_protos[l4proto->l3proto]) {
8f03dea5	286	/* l3proto may be loaded latter. */
605dcad6	287	struct nf_conntrack_l4proto **proto_array;
8f03dea5 MJ	288	int i;
8f03dea5 MJ	289
c6a1e615 PM	290	proto_array = kmalloc(MAX_NF_CT_PROTO *
	291	sizeof(struct nf_conntrack_l4proto *),
	292	GFP_KERNEL);
8f03dea5 MJ	293	if (proto_array == NULL) {
8f03dea5 MJ	294	ret = -ENOMEM;
b19caa0c	295	goto out_unlock;
8f03dea5	296	}
c6a1e615	297
8f03dea5	298	for (i = 0; i < MAX_NF_CT_PROTO; i++)
605dcad6	299	proto_array[i] = &nf_conntrack_l4proto_generic;
c6a1e615 PM	300	nf_ct_protos[l4proto->l3proto] = proto_array;
	301	} else if (nf_ct_protos[l4proto->l3proto][l4proto->l4proto] !=
	302	&nf_conntrack_l4proto_generic) {
	303	ret = -EBUSY;
	304	goto out_unlock;
8f03dea5 MJ	305	}
8f03dea5 MJ	306
d62f9ed4 PM	307	ret = nf_ct_l4proto_register_sysctl(l4proto);
d62f9ed4 PM	308	if (ret < 0)
0661cca9 PM	309	goto out_unlock;
0661cca9 PM	310
c6a1e615 PM	311	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
c6a1e615 PM	312	l4proto);
8f03dea5 MJ	313
8f03dea5 MJ	314	out_unlock:
b19caa0c	315	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5 MJ	316	return ret;
8f03dea5 MJ	317	}
13b18339	318	EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_register);
8f03dea5	319
fe3eb20c	320	void nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
8f03dea5	321	{
678d6675 AD	322	struct net *net;
678d6675 AD	323
fe3eb20c	324	BUG_ON(l4proto->l3proto >= PF_MAX);
ae5718fb	325
b19caa0c	326	mutex_lock(&nf_ct_proto_mutex);
fe3eb20c	327	BUG_ON(nf_ct_protos[l4proto->l3proto][l4proto->l4proto] != l4proto);
923f4902 PM	328	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
923f4902 PM	329	&nf_conntrack_l4proto_generic);
0661cca9	330	nf_ct_l4proto_unregister_sysctl(l4proto);
b19caa0c	331	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	332
0661cca9	333	synchronize_rcu();
d62f9ed4	334
8f03dea5	335	/* Remove all contrack entries for this protocol */
678d6675 AD	336	for_each_net(net)
678d6675 AD	337	nf_ct_iterate_cleanup(net, kill_l4proto, l4proto);
8f03dea5	338	}
13b18339	339	EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_unregister);
ac5357eb PM	340
	341	int nf_conntrack_proto_init(void)
	342	{
	343	unsigned int i;
	344	int err;
	345
	346	err = nf_ct_l4proto_register_sysctl(&nf_conntrack_l4proto_generic);
	347	if (err < 0)
	348	return err;
	349
	350	for (i = 0; i < AF_MAX; i++)
	351	rcu_assign_pointer(nf_ct_l3protos[i],
	352	&nf_conntrack_l3proto_generic);
	353	return 0;
	354	}
	355
	356	void nf_conntrack_proto_fini(void)
	357	{
	358	unsigned int i;
	359
	360	nf_ct_l4proto_unregister_sysctl(&nf_conntrack_l4proto_generic);
	361
	362	/* free l3proto protocol tables */
	363	for (i = 0; i < PF_MAX; i++)
	364	kfree(nf_ct_protos[i]);
	365	}