[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/slab.h>
#include <linux/mutex.h>
#include <linux/vmalloc.h>
#include <linux/stddef.h>
#include <linux/err.h>
#include <linux/percpu.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 __rcu **nf_ct_protos[PF_MAX] __read_mostly;
struct nf_conntrack_l3proto __rcu *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 net *net,
		      struct ctl_table_header **header,
		      const char *path,
		      struct ctl_table *table)
{
	if (*header == NULL) {
		*header = register_net_sysctl(net, path, table);
		if (*header == NULL)
			return -ENOMEM;
	}

	return 0;
}

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

	unregister_net_sysctl_table(*header);
	kfree(*table);
	*header = NULL;
	*table = 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_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, but
	 * taken anyways to avoid lockdep warnings in __nf_ct_l3proto_find()
	 */
	rcu_read_lock();
	p = __nf_ct_l3proto_find(l3proto);
	module_put(p->me);
	rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(nf_ct_l3proto_module_put);

struct nf_conntrack_l4proto *
nf_ct_l4proto_find_get(u_int16_t l3num, u_int8_t l4num)
{
	struct nf_conntrack_l4proto *p;

	rcu_read_lock();
	p = __nf_ct_l4proto_find(l3num, l4num);
	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);

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 struct nf_ip_net *nf_ct_l3proto_net(struct net *net,
					   struct nf_conntrack_l3proto *l3proto)
{
	if (l3proto->l3proto == PF_INET)
		return &net->ct.nf_ct_proto;
	else
		return NULL;
}

static int nf_ct_l3proto_register_sysctl(struct net *net,
					 struct nf_conntrack_l3proto *l3proto)
{
	int err = 0;
	struct nf_ip_net *in = nf_ct_l3proto_net(net, l3proto);
	/* nf_conntrack_l3proto_ipv6 doesn't support sysctl */
	if (in == NULL)
		return 0;

#if defined(CONFIG_SYSCTL) && defined(CONFIG_NF_CONNTRACK_PROC_COMPAT)
	if (in->ctl_table != NULL) {
		err = nf_ct_register_sysctl(net,
					    &in->ctl_table_header,
					    l3proto->ctl_table_path,
					    in->ctl_table);
		if (err < 0) {
			kfree(in->ctl_table);
			in->ctl_table = NULL;
		}
	}
#endif
	return err;
}

static void nf_ct_l3proto_unregister_sysctl(struct net *net,
					    struct nf_conntrack_l3proto *l3proto)
{
	struct nf_ip_net *in = nf_ct_l3proto_net(net, l3proto);

	if (in == NULL)
		return;
#if defined(CONFIG_SYSCTL) && defined(CONFIG_NF_CONNTRACK_PROC_COMPAT)
	if (in->ctl_table_header != NULL)
		nf_ct_unregister_sysctl(&in->ctl_table_header,
					&in->ctl_table,
					0);
#endif
}

int nf_ct_l3proto_register(struct nf_conntrack_l3proto *proto)
{
	int ret = 0;
	struct nf_conntrack_l3proto *old;

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

	if (proto->tuple_to_nlattr && !proto->nlattr_tuple_size)
		return -EINVAL;

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

	if (proto->nlattr_tuple_size)
		proto->nla_size = 3 * proto->nlattr_tuple_size();

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

out_unlock:
	mutex_unlock(&nf_ct_proto_mutex);
	return ret;

}
EXPORT_SYMBOL_GPL(nf_ct_l3proto_register);

int nf_ct_l3proto_pernet_register(struct net *net,
				  struct nf_conntrack_l3proto *proto)
{
	int ret = 0;

	if (proto->init_net) {
		ret = proto->init_net(net);
		if (ret < 0)
			return ret;
	}

	return nf_ct_l3proto_register_sysctl(net, proto);
}
EXPORT_SYMBOL_GPL(nf_ct_l3proto_pernet_register);

void nf_ct_l3proto_unregister(struct nf_conntrack_l3proto *proto)
{
	BUG_ON(proto->l3proto >= AF_MAX);

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

	synchronize_rcu();
}
EXPORT_SYMBOL_GPL(nf_ct_l3proto_unregister);

void nf_ct_l3proto_pernet_unregister(struct net *net,
				     struct nf_conntrack_l3proto *proto)
{
	nf_ct_l3proto_unregister_sysctl(net, proto);

	/* Remove all contrack entries for this protocol */
	nf_ct_iterate_cleanup(net, kill_l3proto, proto);
}
EXPORT_SYMBOL_GPL(nf_ct_l3proto_pernet_unregister);

static struct nf_proto_net *nf_ct_l4proto_net(struct net *net,
					      struct nf_conntrack_l4proto *l4proto)
{
	if (l4proto->get_net_proto) {
		/* statically built-in protocols use static per-net */
		return l4proto->get_net_proto(net);
	} else if (l4proto->net_id) {
		/* ... and loadable protocols use dynamic per-net */
		return net_generic(net, *l4proto->net_id);
	}
	return NULL;
}

static
int nf_ct_l4proto_register_sysctl(struct net *net,
				  struct nf_proto_net *pn,
				  struct nf_conntrack_l4proto *l4proto)
{
	int err = 0;

#ifdef CONFIG_SYSCTL
	if (pn->ctl_table != NULL) {
		err = nf_ct_register_sysctl(net,
					    &pn->ctl_table_header,
					    "net/netfilter",
					    pn->ctl_table);
		if (err < 0) {
			if (!pn->users) {
				kfree(pn->ctl_table);
				pn->ctl_table = NULL;
			}
		}
	}
#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
	if (l4proto->l3proto != AF_INET6 && pn->ctl_compat_table != NULL) {
		if (err < 0) {
			nf_ct_kfree_compat_sysctl_table(pn);
			goto out;
		}
		err = nf_ct_register_sysctl(net,
					    &pn->ctl_compat_header,
					    "net/ipv4/netfilter",
					    pn->ctl_compat_table);
		if (err == 0)
			goto out;

		nf_ct_kfree_compat_sysctl_table(pn);
		nf_ct_unregister_sysctl(&pn->ctl_table_header,
					&pn->ctl_table,
					pn->users);
	}
out:
#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
#endif /* CONFIG_SYSCTL */
	return err;
}

static
void nf_ct_l4proto_unregister_sysctl(struct net *net,
				     struct nf_proto_net *pn,
				     struct nf_conntrack_l4proto *l4proto)
{
#ifdef CONFIG_SYSCTL
	if (pn->ctl_table_header != NULL)
		nf_ct_unregister_sysctl(&pn->ctl_table_header,
					&pn->ctl_table,
					pn->users);

#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
	if (l4proto->l3proto != AF_INET6 && pn->ctl_compat_header != NULL)
		nf_ct_unregister_sysctl(&pn->ctl_compat_header,
					&pn->ctl_compat_table,
					0);
#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
#endif /* CONFIG_SYSCTL */
}

/* FIXME: Allow NULL functions and sub in pointers to generic for
   them. --RR */
int nf_ct_l4proto_register(struct nf_conntrack_l4proto *l4proto)
{
	int ret = 0;

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

	if ((l4proto->to_nlattr && !l4proto->nlattr_size)
		|| (l4proto->tuple_to_nlattr && !l4proto->nlattr_tuple_size))
		return -EINVAL;

	mutex_lock(&nf_ct_proto_mutex);
	if (!nf_ct_protos[l4proto->l3proto]) {
		/* l3proto may be loaded latter. */
		struct nf_conntrack_l4proto __rcu **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++)
			RCU_INIT_POINTER(proto_array[i], &nf_conntrack_l4proto_generic);

		/* Before making proto_array visible to lockless readers,
		 * we must make sure its content is committed to memory.
		 */
		smp_wmb();

		nf_ct_protos[l4proto->l3proto] = proto_array;
	} else if (rcu_dereference_protected(
			nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
			lockdep_is_held(&nf_ct_proto_mutex)
			) != &nf_conntrack_l4proto_generic) {
		ret = -EBUSY;
		goto out_unlock;
	}

	l4proto->nla_size = 0;
	if (l4proto->nlattr_size)
		l4proto->nla_size += l4proto->nlattr_size();
	if (l4proto->nlattr_tuple_size)
		l4proto->nla_size += 3 * l4proto->nlattr_tuple_size();

	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_ct_l4proto_register);

int nf_ct_l4proto_pernet_register(struct net *net,
				  struct nf_conntrack_l4proto *l4proto)
{
	int ret = 0;
	struct nf_proto_net *pn = NULL;

	if (l4proto->init_net) {
		ret = l4proto->init_net(net, l4proto->l3proto);
		if (ret < 0)
			goto out;
	}

	pn = nf_ct_l4proto_net(net, l4proto);
	if (pn == NULL)
		goto out;

	ret = nf_ct_l4proto_register_sysctl(net, pn, l4proto);
	if (ret < 0)
		goto out;

	pn->users++;
out:
	return ret;
}
EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_register);

void nf_ct_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
{
	BUG_ON(l4proto->l3proto >= PF_MAX);

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

	synchronize_rcu();
}
EXPORT_SYMBOL_GPL(nf_ct_l4proto_unregister);

void nf_ct_l4proto_pernet_unregister(struct net *net,
				     struct nf_conntrack_l4proto *l4proto)
{
	struct nf_proto_net *pn = NULL;

	pn = nf_ct_l4proto_net(net, l4proto);
	if (pn == NULL)
		return;

	pn->users--;
	nf_ct_l4proto_unregister_sysctl(net, pn, l4proto);

	/* Remove all contrack entries for this protocol */
	nf_ct_iterate_cleanup(net, kill_l4proto, l4proto);
}
EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_unregister);

int nf_conntrack_proto_pernet_init(struct net *net)
{
	int err;
	struct nf_proto_net *pn = nf_ct_l4proto_net(net,
					&nf_conntrack_l4proto_generic);

	err = nf_conntrack_l4proto_generic.init_net(net,
					nf_conntrack_l4proto_generic.l3proto);
	if (err < 0)
		return err;
	err = nf_ct_l4proto_register_sysctl(net,
					    pn,
					    &nf_conntrack_l4proto_generic);
	if (err < 0)
		return err;

	pn->users++;
	return 0;
}

void nf_conntrack_proto_pernet_fini(struct net *net)
{
	struct nf_proto_net *pn = nf_ct_l4proto_net(net,
					&nf_conntrack_l4proto_generic);

	pn->users--;
	nf_ct_l4proto_unregister_sysctl(net,
					pn,
					&nf_conntrack_l4proto_generic);
}

int nf_conntrack_proto_init(void)
{
	unsigned int i;
	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;
	/* 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>
5a0e3ad6	15	#include <linux/slab.h>
d62f9ed4	16	#include <linux/mutex.h>
8f03dea5 MJ	17	#include <linux/vmalloc.h>
	18	#include <linux/stddef.h>
	19	#include <linux/err.h>
	20	#include <linux/percpu.h>
8f03dea5 MJ	21	#include <linux/notifier.h>
	22	#include <linux/kernel.h>
	23	#include <linux/netdevice.h>
	24
	25	#include <net/netfilter/nf_conntrack.h>
	26	#include <net/netfilter/nf_conntrack_l3proto.h>
605dcad6	27	#include <net/netfilter/nf_conntrack_l4proto.h>
8f03dea5 MJ	28	#include <net/netfilter/nf_conntrack_core.h>
8f03dea5 MJ	29
0906a372 AB	30	static struct nf_conntrack_l4proto __rcu **nf_ct_protos[PF_MAX] __read_mostly;
0906a372 AB	31	struct nf_conntrack_l3proto __rcu *nf_ct_l3protos[AF_MAX] __read_mostly;
13b18339	32	EXPORT_SYMBOL_GPL(nf_ct_l3protos);
8f03dea5	33
b19caa0c	34	static DEFINE_MUTEX(nf_ct_proto_mutex);
d62f9ed4	35
b19caa0c	36	#ifdef CONFIG_SYSCTL
d62f9ed4	37	static int
2c352f44 G	38	nf_ct_register_sysctl(struct net *net,
	39	struct ctl_table_header **header,
	40	const char *path,
fa34fff5	41	struct ctl_table *table)
d62f9ed4 PM	42	{
d62f9ed4 PM	43	if (*header == NULL) {
2c352f44	44	*header = register_net_sysctl(net, path, table);
d62f9ed4 PM	45	if (*header == NULL)
	46	return -ENOMEM;
	47	}
2c352f44	48
d62f9ed4 PM	49	return 0;
	50	}
	51
	52	static void
	53	nf_ct_unregister_sysctl(struct ctl_table_header **header,
2c352f44	54	struct ctl_table **table,
fa34fff5	55	unsigned int users)
d62f9ed4	56	{
fa34fff5	57	if (users > 0)
d62f9ed4	58	return;
b3fd3ffe	59
5dd3df10	60	unregister_net_sysctl_table(*header);
2c352f44	61	kfree(*table);
d62f9ed4	62	*header = NULL;
2c352f44	63	*table = NULL;
d62f9ed4 PM	64	}
	65	#endif
	66
605dcad6 MJ	67	struct nf_conntrack_l4proto *
605dcad6 MJ	68	__nf_ct_l4proto_find(u_int16_t l3proto, u_int8_t l4proto)
8f03dea5 MJ	69	{
8f03dea5 MJ	70	if (unlikely(l3proto >= AF_MAX \|\| nf_ct_protos[l3proto] == NULL))
605dcad6	71	return &nf_conntrack_l4proto_generic;
8f03dea5	72
923f4902	73	return rcu_dereference(nf_ct_protos[l3proto][l4proto]);
8f03dea5	74	}
13b18339	75	EXPORT_SYMBOL_GPL(__nf_ct_l4proto_find);
8f03dea5 MJ	76
	77	/* this is guaranteed to always return a valid protocol helper, since
	78	* it falls back to generic_protocol */
8f03dea5 MJ	79	struct nf_conntrack_l3proto *
	80	nf_ct_l3proto_find_get(u_int16_t l3proto)
	81	{
	82	struct nf_conntrack_l3proto *p;
	83
923f4902	84	rcu_read_lock();
8f03dea5 MJ	85	p = __nf_ct_l3proto_find(l3proto);
8f03dea5 MJ	86	if (!try_module_get(p->me))
605dcad6	87	p = &nf_conntrack_l3proto_generic;
923f4902	88	rcu_read_unlock();
8f03dea5 MJ	89
	90	return p;
	91	}
13b18339	92	EXPORT_SYMBOL_GPL(nf_ct_l3proto_find_get);
8f03dea5 MJ	93
	94	void nf_ct_l3proto_put(struct nf_conntrack_l3proto *p)
	95	{
	96	module_put(p->me);
	97	}
13b18339	98	EXPORT_SYMBOL_GPL(nf_ct_l3proto_put);
8f03dea5 MJ	99
	100	int
	101	nf_ct_l3proto_try_module_get(unsigned short l3proto)
	102	{
	103	int ret;
	104	struct nf_conntrack_l3proto *p;
	105
	106	retry: p = nf_ct_l3proto_find_get(l3proto);
605dcad6	107	if (p == &nf_conntrack_l3proto_generic) {
8f03dea5 MJ	108	ret = request_module("nf_conntrack-%d", l3proto);
	109	if (!ret)
	110	goto retry;
	111
	112	return -EPROTOTYPE;
	113	}
	114
	115	return 0;
	116	}
13b18339	117	EXPORT_SYMBOL_GPL(nf_ct_l3proto_try_module_get);
8f03dea5 MJ	118
	119	void nf_ct_l3proto_module_put(unsigned short l3proto)
	120	{
	121	struct nf_conntrack_l3proto *p;
	122
3b254c54 PM	123	/* rcu_read_lock not necessary since the caller holds a reference, but
	124	* taken anyways to avoid lockdep warnings in __nf_ct_l3proto_find()
	125	*/
	126	rcu_read_lock();
8f03dea5	127	p = __nf_ct_l3proto_find(l3proto);
8f03dea5	128	module_put(p->me);
3b254c54	129	rcu_read_unlock();
8f03dea5	130	}
13b18339	131	EXPORT_SYMBOL_GPL(nf_ct_l3proto_module_put);
8f03dea5	132
c1ebd7df PNA	133	struct nf_conntrack_l4proto *
	134	nf_ct_l4proto_find_get(u_int16_t l3num, u_int8_t l4num)
	135	{
	136	struct nf_conntrack_l4proto *p;
	137
	138	rcu_read_lock();
	139	p = __nf_ct_l4proto_find(l3num, l4num);
	140	if (!try_module_get(p->me))
	141	p = &nf_conntrack_l4proto_generic;
	142	rcu_read_unlock();
	143
	144	return p;
	145	}
	146	EXPORT_SYMBOL_GPL(nf_ct_l4proto_find_get);
	147
	148	void nf_ct_l4proto_put(struct nf_conntrack_l4proto *p)
	149	{
	150	module_put(p->me);
	151	}
	152	EXPORT_SYMBOL_GPL(nf_ct_l4proto_put);
	153
8f03dea5 MJ	154	static int kill_l3proto(struct nf_conn i, void data)
8f03dea5 MJ	155	{
5e8fbe2a	156	return nf_ct_l3num(i) == ((struct nf_conntrack_l3proto *)data)->l3proto;
8f03dea5 MJ	157	}
8f03dea5 MJ	158
605dcad6	159	static int kill_l4proto(struct nf_conn i, void data)
8f03dea5	160	{
605dcad6 MJ	161	struct nf_conntrack_l4proto *l4proto;
605dcad6 MJ	162	l4proto = (struct nf_conntrack_l4proto *)data;
5e8fbe2a PM	163	return nf_ct_protonum(i) == l4proto->l4proto &&
5e8fbe2a PM	164	nf_ct_l3num(i) == l4proto->l3proto;
8f03dea5 MJ	165	}
8f03dea5 MJ	166
524a53e5 G	167	static struct nf_ip_net nf_ct_l3proto_net(struct net net,
524a53e5 G	168	struct nf_conntrack_l3proto *l3proto)
d62f9ed4	169	{
524a53e5 G	170	if (l3proto->l3proto == PF_INET)
	171	return &net->ct.nf_ct_proto;
	172	else
	173	return NULL;
	174	}
d62f9ed4	175
524a53e5 G	176	static int nf_ct_l3proto_register_sysctl(struct net *net,
	177	struct nf_conntrack_l3proto *l3proto)
	178	{
	179	int err = 0;
	180	struct nf_ip_net *in = nf_ct_l3proto_net(net, l3proto);
	181	/* nf_conntrack_l3proto_ipv6 doesn't support sysctl */
	182	if (in == NULL)
	183	return 0;
	184
	185	#if defined(CONFIG_SYSCTL) && defined(CONFIG_NF_CONNTRACK_PROC_COMPAT)
	186	if (in->ctl_table != NULL) {
	187	err = nf_ct_register_sysctl(net,
	188	&in->ctl_table_header,
d62f9ed4	189	l3proto->ctl_table_path,
fa34fff5	190	in->ctl_table);
524a53e5 G	191	if (err < 0) {
	192	kfree(in->ctl_table);
	193	in->ctl_table = NULL;
	194	}
d62f9ed4	195	}
d62f9ed4 PM	196	#endif
	197	return err;
	198	}
	199
524a53e5 G	200	static void nf_ct_l3proto_unregister_sysctl(struct net *net,
524a53e5 G	201	struct nf_conntrack_l3proto *l3proto)
d62f9ed4	202	{
524a53e5 G	203	struct nf_ip_net *in = nf_ct_l3proto_net(net, l3proto);
	204
	205	if (in == NULL)
	206	return;
	207	#if defined(CONFIG_SYSCTL) && defined(CONFIG_NF_CONNTRACK_PROC_COMPAT)
	208	if (in->ctl_table_header != NULL)
	209	nf_ct_unregister_sysctl(&in->ctl_table_header,
	210	&in->ctl_table,
fa34fff5	211	0);
d62f9ed4 PM	212	#endif
	213	}
	214
6330750d	215	int nf_ct_l3proto_register(struct nf_conntrack_l3proto *proto)
8f03dea5 MJ	216	{
8f03dea5 MJ	217	int ret = 0;
0e60ebe0	218	struct nf_conntrack_l3proto *old;
8f03dea5	219
0661cca9 PM	220	if (proto->l3proto >= AF_MAX)
0661cca9 PM	221	return -EBUSY;
ae5718fb	222
d0dba725 HE	223	if (proto->tuple_to_nlattr && !proto->nlattr_tuple_size)
	224	return -EINVAL;
	225
b19caa0c	226	mutex_lock(&nf_ct_proto_mutex);
0e60ebe0 ED	227	old = rcu_dereference_protected(nf_ct_l3protos[proto->l3proto],
	228	lockdep_is_held(&nf_ct_proto_mutex));
	229	if (old != &nf_conntrack_l3proto_generic) {
8f03dea5	230	ret = -EBUSY;
ae5718fb	231	goto out_unlock;
8f03dea5	232	}
d62f9ed4	233
d0dba725 HE	234	if (proto->nlattr_tuple_size)
	235	proto->nla_size = 3 * proto->nlattr_tuple_size();
	236
0661cca9	237	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto], proto);
8f03dea5	238
ae5718fb	239	out_unlock:
b19caa0c	240	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	241	return ret;
524a53e5	242
8f03dea5	243	}
6330750d	244	EXPORT_SYMBOL_GPL(nf_ct_l3proto_register);
8f03dea5	245
6330750d	246	int nf_ct_l3proto_pernet_register(struct net *net,
524a53e5	247	struct nf_conntrack_l3proto *proto)
8f03dea5	248	{
524a53e5 G	249	int ret = 0;
524a53e5 G	250
fa0f61f0 G	251	if (proto->init_net) {
	252	ret = proto->init_net(net);
	253	if (ret < 0)
	254	return ret;
	255	}
524a53e5	256
6330750d	257	return nf_ct_l3proto_register_sysctl(net, proto);
524a53e5	258	}
6330750d	259	EXPORT_SYMBOL_GPL(nf_ct_l3proto_pernet_register);
678d6675	260
6330750d	261	void nf_ct_l3proto_unregister(struct nf_conntrack_l3proto *proto)
524a53e5	262	{
fe3eb20c	263	BUG_ON(proto->l3proto >= AF_MAX);
ae5718fb	264
b19caa0c	265	mutex_lock(&nf_ct_proto_mutex);
0e60ebe0 ED	266	BUG_ON(rcu_dereference_protected(nf_ct_l3protos[proto->l3proto],
	267	lockdep_is_held(&nf_ct_proto_mutex)
	268	) != proto);
923f4902 PM	269	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto],
923f4902 PM	270	&nf_conntrack_l3proto_generic);
b19caa0c	271	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	272
0661cca9	273	synchronize_rcu();
524a53e5	274	}
6330750d	275	EXPORT_SYMBOL_GPL(nf_ct_l3proto_unregister);
524a53e5	276
6330750d	277	void nf_ct_l3proto_pernet_unregister(struct net *net,
524a53e5 G	278	struct nf_conntrack_l3proto *proto)
524a53e5 G	279	{
524a53e5	280	nf_ct_l3proto_unregister_sysctl(net, proto);
d62f9ed4	281
8f03dea5	282	/* Remove all contrack entries for this protocol */
524a53e5	283	nf_ct_iterate_cleanup(net, kill_l3proto, proto);
8f03dea5	284	}
6330750d	285	EXPORT_SYMBOL_GPL(nf_ct_l3proto_pernet_unregister);
8f03dea5	286
2c352f44 G	287	static struct nf_proto_net nf_ct_l4proto_net(struct net net,
	288	struct nf_conntrack_l4proto *l4proto)
	289	{
08911475 PNA	290	if (l4proto->get_net_proto) {
	291	/* statically built-in protocols use static per-net */
	292	return l4proto->get_net_proto(net);
	293	} else if (l4proto->net_id) {
	294	/* ... and loadable protocols use dynamic per-net */
	295	return net_generic(net, *l4proto->net_id);
15f585bd G	296	}
15f585bd G	297	return NULL;
2c352f44 G	298	}
	299
	300	static
	301	int nf_ct_l4proto_register_sysctl(struct net *net,
fa34fff5	302	struct nf_proto_net *pn,
2c352f44	303	struct nf_conntrack_l4proto *l4proto)
d62f9ed4 PM	304	{
	305	int err = 0;
	306
	307	#ifdef CONFIG_SYSCTL
2c352f44 G	308	if (pn->ctl_table != NULL) {
	309	err = nf_ct_register_sysctl(net,
	310	&pn->ctl_table_header,
f99e8f71	311	"net/netfilter",
fa34fff5	312	pn->ctl_table);
2c352f44 G	313	if (err < 0) {
	314	if (!pn->users) {
	315	kfree(pn->ctl_table);
	316	pn->ctl_table = NULL;
	317	}
2c352f44	318	}
d62f9ed4	319	}
a999e683	320	#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
2c352f44	321	if (l4proto->l3proto != AF_INET6 && pn->ctl_compat_table != NULL) {
12c26df3 G	322	if (err < 0) {
	323	nf_ct_kfree_compat_sysctl_table(pn);
	324	goto out;
	325	}
2c352f44 G	326	err = nf_ct_register_sysctl(net,
2c352f44 G	327	&pn->ctl_compat_header,
f99e8f71	328	"net/ipv4/netfilter",
fa34fff5	329	pn->ctl_compat_table);
a999e683 PM	330	if (err == 0)
a999e683 PM	331	goto out;
2c352f44	332
f28997e2	333	nf_ct_kfree_compat_sysctl_table(pn);
2c352f44 G	334	nf_ct_unregister_sysctl(&pn->ctl_table_header,
2c352f44 G	335	&pn->ctl_table,
fa34fff5	336	pn->users);
a999e683	337	}
a999e683	338	out:
12c26df3	339	#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
933a41e7	340	#endif /* CONFIG_SYSCTL */
d62f9ed4 PM	341	return err;
	342	}
	343
2c352f44 G	344	static
2c352f44 G	345	void nf_ct_l4proto_unregister_sysctl(struct net *net,
fa34fff5	346	struct nf_proto_net *pn,
2c352f44	347	struct nf_conntrack_l4proto *l4proto)
d62f9ed4 PM	348	{
d62f9ed4 PM	349	#ifdef CONFIG_SYSCTL
2c352f44 G	350	if (pn->ctl_table_header != NULL)
	351	nf_ct_unregister_sysctl(&pn->ctl_table_header,
	352	&pn->ctl_table,
fa34fff5	353	pn->users);
2c352f44	354
a999e683	355	#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
2c352f44 G	356	if (l4proto->l3proto != AF_INET6 && pn->ctl_compat_header != NULL)
	357	nf_ct_unregister_sysctl(&pn->ctl_compat_header,
	358	&pn->ctl_compat_table,
fa34fff5	359	0);
a999e683	360	#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
933a41e7	361	#endif /* CONFIG_SYSCTL */
d62f9ed4 PM	362	}
d62f9ed4 PM	363
8f03dea5 MJ	364	/* FIXME: Allow NULL functions and sub in pointers to generic for
8f03dea5 MJ	365	them. --RR */
c296bb4d	366	int nf_ct_l4proto_register(struct nf_conntrack_l4proto *l4proto)
8f03dea5 MJ	367	{
	368	int ret = 0;
	369
0661cca9 PM	370	if (l4proto->l3proto >= PF_MAX)
0661cca9 PM	371	return -EBUSY;
ae5718fb	372
d0dba725 HE	373	if ((l4proto->to_nlattr && !l4proto->nlattr_size)
	374	\|\| (l4proto->tuple_to_nlattr && !l4proto->nlattr_tuple_size))
	375	return -EINVAL;
	376
b19caa0c	377	mutex_lock(&nf_ct_proto_mutex);
c6a1e615	378	if (!nf_ct_protos[l4proto->l3proto]) {
8f03dea5	379	/* l3proto may be loaded latter. */
c5d277d2	380	struct nf_conntrack_l4proto __rcu **proto_array;
8f03dea5 MJ	381	int i;
8f03dea5 MJ	382
c6a1e615 PM	383	proto_array = kmalloc(MAX_NF_CT_PROTO *
	384	sizeof(struct nf_conntrack_l4proto *),
	385	GFP_KERNEL);
8f03dea5 MJ	386	if (proto_array == NULL) {
8f03dea5 MJ	387	ret = -ENOMEM;
b19caa0c	388	goto out_unlock;
8f03dea5	389	}
c6a1e615	390
8f03dea5	391	for (i = 0; i < MAX_NF_CT_PROTO; i++)
c5d277d2	392	RCU_INIT_POINTER(proto_array[i], &nf_conntrack_l4proto_generic);
d817d29d ED	393
	394	/* Before making proto_array visible to lockless readers,
	395	* we must make sure its content is committed to memory.
	396	*/
	397	smp_wmb();
	398
c6a1e615	399	nf_ct_protos[l4proto->l3proto] = proto_array;
0e60ebe0 ED	400	} else if (rcu_dereference_protected(
	401	nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
	402	lockdep_is_held(&nf_ct_proto_mutex)
	403	) != &nf_conntrack_l4proto_generic) {
c6a1e615 PM	404	ret = -EBUSY;
c6a1e615 PM	405	goto out_unlock;
8f03dea5 MJ	406	}
8f03dea5 MJ	407
d0dba725 HE	408	l4proto->nla_size = 0;
	409	if (l4proto->nlattr_size)
	410	l4proto->nla_size += l4proto->nlattr_size();
	411	if (l4proto->nlattr_tuple_size)
	412	l4proto->nla_size += 3 * l4proto->nlattr_tuple_size();
	413
c6a1e615 PM	414	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
c6a1e615 PM	415	l4proto);
8f03dea5	416	out_unlock:
b19caa0c	417	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5 MJ	418	return ret;
8f03dea5 MJ	419	}
c296bb4d	420	EXPORT_SYMBOL_GPL(nf_ct_l4proto_register);
8f03dea5	421
c296bb4d	422	int nf_ct_l4proto_pernet_register(struct net *net,
2c352f44	423	struct nf_conntrack_l4proto *l4proto)
8f03dea5	424	{
2c352f44	425	int ret = 0;
fa34fff5	426	struct nf_proto_net *pn = NULL;
2c352f44	427
fa0f61f0	428	if (l4proto->init_net) {
f1caad27	429	ret = l4proto->init_net(net, l4proto->l3proto);
fa0f61f0	430	if (ret < 0)
fa34fff5	431	goto out;
fa0f61f0	432	}
678d6675	433
fa34fff5 G	434	pn = nf_ct_l4proto_net(net, l4proto);
	435	if (pn == NULL)
	436	goto out;
	437
	438	ret = nf_ct_l4proto_register_sysctl(net, pn, l4proto);
2c352f44	439	if (ret < 0)
fa34fff5	440	goto out;
2c352f44	441
fa34fff5 G	442	pn->users++;
fa34fff5 G	443	out:
fa0f61f0	444	return ret;
2c352f44	445	}
c296bb4d	446	EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_register);
2c352f44	447
c296bb4d	448	void nf_ct_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
2c352f44	449	{
fe3eb20c	450	BUG_ON(l4proto->l3proto >= PF_MAX);
ae5718fb	451
b19caa0c	452	mutex_lock(&nf_ct_proto_mutex);
0e60ebe0 ED	453	BUG_ON(rcu_dereference_protected(
	454	nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
	455	lockdep_is_held(&nf_ct_proto_mutex)
	456	) != l4proto);
923f4902 PM	457	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
923f4902 PM	458	&nf_conntrack_l4proto_generic);
b19caa0c	459	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	460
0661cca9	461	synchronize_rcu();
2c352f44	462	}
c296bb4d	463	EXPORT_SYMBOL_GPL(nf_ct_l4proto_unregister);
d62f9ed4	464
c296bb4d	465	void nf_ct_l4proto_pernet_unregister(struct net *net,
2c352f44 G	466	struct nf_conntrack_l4proto *l4proto)
2c352f44 G	467	{
fa34fff5 G	468	struct nf_proto_net *pn = NULL;
fa34fff5 G	469
fa34fff5 G	470	pn = nf_ct_l4proto_net(net, l4proto);
	471	if (pn == NULL)
	472	return;
	473
	474	pn->users--;
	475	nf_ct_l4proto_unregister_sysctl(net, pn, l4proto);
	476
8f03dea5	477	/* Remove all contrack entries for this protocol */
2c352f44	478	nf_ct_iterate_cleanup(net, kill_l4proto, l4proto);
8f03dea5	479	}
c296bb4d	480	EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_unregister);
ac5357eb	481
04d87001	482	int nf_conntrack_proto_pernet_init(struct net *net)
ac5357eb	483	{
ac5357eb	484	int err;
fa34fff5 G	485	struct nf_proto_net *pn = nf_ct_l4proto_net(net,
	486	&nf_conntrack_l4proto_generic);
	487
f1caad27 G	488	err = nf_conntrack_l4proto_generic.init_net(net,
f1caad27 G	489	nf_conntrack_l4proto_generic.l3proto);
15f585bd G	490	if (err < 0)
	491	return err;
	492	err = nf_ct_l4proto_register_sysctl(net,
fa34fff5	493	pn,
15f585bd	494	&nf_conntrack_l4proto_generic);
ac5357eb PM	495	if (err < 0)
	496	return err;
	497
fa34fff5	498	pn->users++;
ac5357eb PM	499	return 0;
	500	}
	501
04d87001	502	void nf_conntrack_proto_pernet_fini(struct net *net)
ac5357eb	503	{
fa34fff5 G	504	struct nf_proto_net *pn = nf_ct_l4proto_net(net,
	505	&nf_conntrack_l4proto_generic);
	506
	507	pn->users--;
15f585bd	508	nf_ct_l4proto_unregister_sysctl(net,
fa34fff5	509	pn,
15f585bd	510	&nf_conntrack_l4proto_generic);
04d87001 G	511	}
	512
	513	int nf_conntrack_proto_init(void)
	514	{
	515	unsigned int i;
	516	for (i = 0; i < AF_MAX; i++)
	517	rcu_assign_pointer(nf_ct_l3protos[i],
	518	&nf_conntrack_l3proto_generic);
	519	return 0;
	520	}
	521
	522	void nf_conntrack_proto_fini(void)
	523	{
	524	unsigned int i;
	525	/* free l3proto protocol tables */
	526	for (i = 0; i < PF_MAX; i++)
	527	kfree(nf_ct_protos[i]);
ac5357eb	528	}