[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>
 * (C) 2006-2012 Patrick McHardy <kaber@trash.net>
 *
 * 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, 0, 0);
}
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, 0, 0);
}
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>
f229f6ce	6	* (C) 2006-2012 Patrick McHardy <kaber@trash.net>
8f03dea5 MJ	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*/
	12
	13	#include <linux/types.h>
	14	#include <linux/netfilter.h>
	15	#include <linux/module.h>
5a0e3ad6	16	#include <linux/slab.h>
d62f9ed4	17	#include <linux/mutex.h>
8f03dea5 MJ	18	#include <linux/vmalloc.h>
	19	#include <linux/stddef.h>
	20	#include <linux/err.h>
	21	#include <linux/percpu.h>
8f03dea5 MJ	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
0906a372 AB	31	static struct nf_conntrack_l4proto __rcu **nf_ct_protos[PF_MAX] __read_mostly;
0906a372 AB	32	struct nf_conntrack_l3proto __rcu *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
2c352f44 G	39	nf_ct_register_sysctl(struct net *net,
	40	struct ctl_table_header **header,
	41	const char *path,
fa34fff5	42	struct ctl_table *table)
d62f9ed4 PM	43	{
d62f9ed4 PM	44	if (*header == NULL) {
2c352f44	45	*header = register_net_sysctl(net, path, table);
d62f9ed4 PM	46	if (*header == NULL)
	47	return -ENOMEM;
	48	}
2c352f44	49
d62f9ed4 PM	50	return 0;
	51	}
	52
	53	static void
	54	nf_ct_unregister_sysctl(struct ctl_table_header **header,
2c352f44	55	struct ctl_table **table,
fa34fff5	56	unsigned int users)
d62f9ed4	57	{
fa34fff5	58	if (users > 0)
d62f9ed4	59	return;
b3fd3ffe	60
5dd3df10	61	unregister_net_sysctl_table(*header);
2c352f44	62	kfree(*table);
d62f9ed4	63	*header = NULL;
2c352f44	64	*table = NULL;
d62f9ed4 PM	65	}
	66	#endif
	67
605dcad6 MJ	68	struct nf_conntrack_l4proto *
605dcad6 MJ	69	__nf_ct_l4proto_find(u_int16_t l3proto, u_int8_t l4proto)
8f03dea5 MJ	70	{
8f03dea5 MJ	71	if (unlikely(l3proto >= AF_MAX \|\| nf_ct_protos[l3proto] == NULL))
605dcad6	72	return &nf_conntrack_l4proto_generic;
8f03dea5	73
923f4902	74	return rcu_dereference(nf_ct_protos[l3proto][l4proto]);
8f03dea5	75	}
13b18339	76	EXPORT_SYMBOL_GPL(__nf_ct_l4proto_find);
8f03dea5 MJ	77
	78	/* this is guaranteed to always return a valid protocol helper, since
	79	* it falls back to generic_protocol */
8f03dea5 MJ	80	struct nf_conntrack_l3proto *
	81	nf_ct_l3proto_find_get(u_int16_t l3proto)
	82	{
	83	struct nf_conntrack_l3proto *p;
	84
923f4902	85	rcu_read_lock();
8f03dea5 MJ	86	p = __nf_ct_l3proto_find(l3proto);
8f03dea5 MJ	87	if (!try_module_get(p->me))
605dcad6	88	p = &nf_conntrack_l3proto_generic;
923f4902	89	rcu_read_unlock();
8f03dea5 MJ	90
	91	return p;
	92	}
13b18339	93	EXPORT_SYMBOL_GPL(nf_ct_l3proto_find_get);
8f03dea5 MJ	94
	95	void nf_ct_l3proto_put(struct nf_conntrack_l3proto *p)
	96	{
	97	module_put(p->me);
	98	}
13b18339	99	EXPORT_SYMBOL_GPL(nf_ct_l3proto_put);
8f03dea5 MJ	100
	101	int
	102	nf_ct_l3proto_try_module_get(unsigned short l3proto)
	103	{
	104	int ret;
	105	struct nf_conntrack_l3proto *p;
	106
	107	retry: p = nf_ct_l3proto_find_get(l3proto);
605dcad6	108	if (p == &nf_conntrack_l3proto_generic) {
8f03dea5 MJ	109	ret = request_module("nf_conntrack-%d", l3proto);
	110	if (!ret)
	111	goto retry;
	112
	113	return -EPROTOTYPE;
	114	}
	115
	116	return 0;
	117	}
13b18339	118	EXPORT_SYMBOL_GPL(nf_ct_l3proto_try_module_get);
8f03dea5 MJ	119
	120	void nf_ct_l3proto_module_put(unsigned short l3proto)
	121	{
	122	struct nf_conntrack_l3proto *p;
	123
3b254c54 PM	124	/* rcu_read_lock not necessary since the caller holds a reference, but
	125	* taken anyways to avoid lockdep warnings in __nf_ct_l3proto_find()
	126	*/
	127	rcu_read_lock();
8f03dea5	128	p = __nf_ct_l3proto_find(l3proto);
8f03dea5	129	module_put(p->me);
3b254c54	130	rcu_read_unlock();
8f03dea5	131	}
13b18339	132	EXPORT_SYMBOL_GPL(nf_ct_l3proto_module_put);
8f03dea5	133
c1ebd7df PNA	134	struct nf_conntrack_l4proto *
	135	nf_ct_l4proto_find_get(u_int16_t l3num, u_int8_t l4num)
	136	{
	137	struct nf_conntrack_l4proto *p;
	138
	139	rcu_read_lock();
	140	p = __nf_ct_l4proto_find(l3num, l4num);
	141	if (!try_module_get(p->me))
	142	p = &nf_conntrack_l4proto_generic;
	143	rcu_read_unlock();
	144
	145	return p;
	146	}
	147	EXPORT_SYMBOL_GPL(nf_ct_l4proto_find_get);
	148
	149	void nf_ct_l4proto_put(struct nf_conntrack_l4proto *p)
	150	{
	151	module_put(p->me);
	152	}
	153	EXPORT_SYMBOL_GPL(nf_ct_l4proto_put);
	154
8f03dea5 MJ	155	static int kill_l3proto(struct nf_conn i, void data)
8f03dea5 MJ	156	{
5e8fbe2a	157	return nf_ct_l3num(i) == ((struct nf_conntrack_l3proto *)data)->l3proto;
8f03dea5 MJ	158	}
8f03dea5 MJ	159
605dcad6	160	static int kill_l4proto(struct nf_conn i, void data)
8f03dea5	161	{
605dcad6 MJ	162	struct nf_conntrack_l4proto *l4proto;
605dcad6 MJ	163	l4proto = (struct nf_conntrack_l4proto *)data;
5e8fbe2a PM	164	return nf_ct_protonum(i) == l4proto->l4proto &&
5e8fbe2a PM	165	nf_ct_l3num(i) == l4proto->l3proto;
8f03dea5 MJ	166	}
8f03dea5 MJ	167
524a53e5 G	168	static struct nf_ip_net nf_ct_l3proto_net(struct net net,
524a53e5 G	169	struct nf_conntrack_l3proto *l3proto)
d62f9ed4	170	{
524a53e5 G	171	if (l3proto->l3proto == PF_INET)
	172	return &net->ct.nf_ct_proto;
	173	else
	174	return NULL;
	175	}
d62f9ed4	176
524a53e5 G	177	static int nf_ct_l3proto_register_sysctl(struct net *net,
	178	struct nf_conntrack_l3proto *l3proto)
	179	{
	180	int err = 0;
	181	struct nf_ip_net *in = nf_ct_l3proto_net(net, l3proto);
	182	/* nf_conntrack_l3proto_ipv6 doesn't support sysctl */
	183	if (in == NULL)
	184	return 0;
	185
	186	#if defined(CONFIG_SYSCTL) && defined(CONFIG_NF_CONNTRACK_PROC_COMPAT)
	187	if (in->ctl_table != NULL) {
	188	err = nf_ct_register_sysctl(net,
	189	&in->ctl_table_header,
d62f9ed4	190	l3proto->ctl_table_path,
fa34fff5	191	in->ctl_table);
524a53e5 G	192	if (err < 0) {
	193	kfree(in->ctl_table);
	194	in->ctl_table = NULL;
	195	}
d62f9ed4	196	}
d62f9ed4 PM	197	#endif
	198	return err;
	199	}
	200
524a53e5 G	201	static void nf_ct_l3proto_unregister_sysctl(struct net *net,
524a53e5 G	202	struct nf_conntrack_l3proto *l3proto)
d62f9ed4	203	{
524a53e5 G	204	struct nf_ip_net *in = nf_ct_l3proto_net(net, l3proto);
	205
	206	if (in == NULL)
	207	return;
	208	#if defined(CONFIG_SYSCTL) && defined(CONFIG_NF_CONNTRACK_PROC_COMPAT)
	209	if (in->ctl_table_header != NULL)
	210	nf_ct_unregister_sysctl(&in->ctl_table_header,
	211	&in->ctl_table,
fa34fff5	212	0);
d62f9ed4 PM	213	#endif
	214	}
	215
6330750d	216	int nf_ct_l3proto_register(struct nf_conntrack_l3proto *proto)
8f03dea5 MJ	217	{
8f03dea5 MJ	218	int ret = 0;
0e60ebe0	219	struct nf_conntrack_l3proto *old;
8f03dea5	220
0661cca9 PM	221	if (proto->l3proto >= AF_MAX)
0661cca9 PM	222	return -EBUSY;
ae5718fb	223
d0dba725 HE	224	if (proto->tuple_to_nlattr && !proto->nlattr_tuple_size)
	225	return -EINVAL;
	226
b19caa0c	227	mutex_lock(&nf_ct_proto_mutex);
0e60ebe0 ED	228	old = rcu_dereference_protected(nf_ct_l3protos[proto->l3proto],
	229	lockdep_is_held(&nf_ct_proto_mutex));
	230	if (old != &nf_conntrack_l3proto_generic) {
8f03dea5	231	ret = -EBUSY;
ae5718fb	232	goto out_unlock;
8f03dea5	233	}
d62f9ed4	234
d0dba725 HE	235	if (proto->nlattr_tuple_size)
	236	proto->nla_size = 3 * proto->nlattr_tuple_size();
	237
0661cca9	238	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto], proto);
8f03dea5	239
ae5718fb	240	out_unlock:
b19caa0c	241	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	242	return ret;
524a53e5	243
8f03dea5	244	}
6330750d	245	EXPORT_SYMBOL_GPL(nf_ct_l3proto_register);
8f03dea5	246
6330750d	247	int nf_ct_l3proto_pernet_register(struct net *net,
524a53e5	248	struct nf_conntrack_l3proto *proto)
8f03dea5	249	{
524a53e5 G	250	int ret = 0;
524a53e5 G	251
fa0f61f0 G	252	if (proto->init_net) {
	253	ret = proto->init_net(net);
	254	if (ret < 0)
	255	return ret;
	256	}
524a53e5	257
6330750d	258	return nf_ct_l3proto_register_sysctl(net, proto);
524a53e5	259	}
6330750d	260	EXPORT_SYMBOL_GPL(nf_ct_l3proto_pernet_register);
678d6675	261
6330750d	262	void nf_ct_l3proto_unregister(struct nf_conntrack_l3proto *proto)
524a53e5	263	{
fe3eb20c	264	BUG_ON(proto->l3proto >= AF_MAX);
ae5718fb	265
b19caa0c	266	mutex_lock(&nf_ct_proto_mutex);
0e60ebe0 ED	267	BUG_ON(rcu_dereference_protected(nf_ct_l3protos[proto->l3proto],
	268	lockdep_is_held(&nf_ct_proto_mutex)
	269	) != proto);
923f4902 PM	270	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto],
923f4902 PM	271	&nf_conntrack_l3proto_generic);
b19caa0c	272	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	273
0661cca9	274	synchronize_rcu();
524a53e5	275	}
6330750d	276	EXPORT_SYMBOL_GPL(nf_ct_l3proto_unregister);
524a53e5	277
6330750d	278	void nf_ct_l3proto_pernet_unregister(struct net *net,
524a53e5 G	279	struct nf_conntrack_l3proto *proto)
524a53e5 G	280	{
524a53e5	281	nf_ct_l3proto_unregister_sysctl(net, proto);
d62f9ed4	282
8f03dea5	283	/* Remove all contrack entries for this protocol */
c655bc68	284	nf_ct_iterate_cleanup(net, kill_l3proto, proto, 0, 0);
8f03dea5	285	}
6330750d	286	EXPORT_SYMBOL_GPL(nf_ct_l3proto_pernet_unregister);
8f03dea5	287
2c352f44 G	288	static struct nf_proto_net nf_ct_l4proto_net(struct net net,
	289	struct nf_conntrack_l4proto *l4proto)
	290	{
08911475 PNA	291	if (l4proto->get_net_proto) {
	292	/* statically built-in protocols use static per-net */
	293	return l4proto->get_net_proto(net);
	294	} else if (l4proto->net_id) {
	295	/* ... and loadable protocols use dynamic per-net */
	296	return net_generic(net, *l4proto->net_id);
15f585bd G	297	}
15f585bd G	298	return NULL;
2c352f44 G	299	}
	300
	301	static
	302	int nf_ct_l4proto_register_sysctl(struct net *net,
fa34fff5	303	struct nf_proto_net *pn,
2c352f44	304	struct nf_conntrack_l4proto *l4proto)
d62f9ed4 PM	305	{
	306	int err = 0;
	307
	308	#ifdef CONFIG_SYSCTL
2c352f44 G	309	if (pn->ctl_table != NULL) {
	310	err = nf_ct_register_sysctl(net,
	311	&pn->ctl_table_header,
f99e8f71	312	"net/netfilter",
fa34fff5	313	pn->ctl_table);
2c352f44 G	314	if (err < 0) {
	315	if (!pn->users) {
	316	kfree(pn->ctl_table);
	317	pn->ctl_table = NULL;
	318	}
2c352f44	319	}
d62f9ed4	320	}
a999e683	321	#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
2c352f44	322	if (l4proto->l3proto != AF_INET6 && pn->ctl_compat_table != NULL) {
12c26df3 G	323	if (err < 0) {
	324	nf_ct_kfree_compat_sysctl_table(pn);
	325	goto out;
	326	}
2c352f44 G	327	err = nf_ct_register_sysctl(net,
2c352f44 G	328	&pn->ctl_compat_header,
f99e8f71	329	"net/ipv4/netfilter",
fa34fff5	330	pn->ctl_compat_table);
a999e683 PM	331	if (err == 0)
a999e683 PM	332	goto out;
2c352f44	333
f28997e2	334	nf_ct_kfree_compat_sysctl_table(pn);
2c352f44 G	335	nf_ct_unregister_sysctl(&pn->ctl_table_header,
2c352f44 G	336	&pn->ctl_table,
fa34fff5	337	pn->users);
a999e683	338	}
a999e683	339	out:
12c26df3	340	#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
933a41e7	341	#endif /* CONFIG_SYSCTL */
d62f9ed4 PM	342	return err;
	343	}
	344
2c352f44 G	345	static
2c352f44 G	346	void nf_ct_l4proto_unregister_sysctl(struct net *net,
fa34fff5	347	struct nf_proto_net *pn,
2c352f44	348	struct nf_conntrack_l4proto *l4proto)
d62f9ed4 PM	349	{
d62f9ed4 PM	350	#ifdef CONFIG_SYSCTL
2c352f44 G	351	if (pn->ctl_table_header != NULL)
	352	nf_ct_unregister_sysctl(&pn->ctl_table_header,
	353	&pn->ctl_table,
fa34fff5	354	pn->users);
2c352f44	355
a999e683	356	#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
2c352f44 G	357	if (l4proto->l3proto != AF_INET6 && pn->ctl_compat_header != NULL)
	358	nf_ct_unregister_sysctl(&pn->ctl_compat_header,
	359	&pn->ctl_compat_table,
fa34fff5	360	0);
a999e683	361	#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
933a41e7	362	#endif /* CONFIG_SYSCTL */
d62f9ed4 PM	363	}
d62f9ed4 PM	364
8f03dea5 MJ	365	/* FIXME: Allow NULL functions and sub in pointers to generic for
8f03dea5 MJ	366	them. --RR */
c296bb4d	367	int nf_ct_l4proto_register(struct nf_conntrack_l4proto *l4proto)
8f03dea5 MJ	368	{
	369	int ret = 0;
	370
0661cca9 PM	371	if (l4proto->l3proto >= PF_MAX)
0661cca9 PM	372	return -EBUSY;
ae5718fb	373
d0dba725 HE	374	if ((l4proto->to_nlattr && !l4proto->nlattr_size)
	375	\|\| (l4proto->tuple_to_nlattr && !l4proto->nlattr_tuple_size))
	376	return -EINVAL;
	377
b19caa0c	378	mutex_lock(&nf_ct_proto_mutex);
c6a1e615	379	if (!nf_ct_protos[l4proto->l3proto]) {
8f03dea5	380	/* l3proto may be loaded latter. */
c5d277d2	381	struct nf_conntrack_l4proto __rcu **proto_array;
8f03dea5 MJ	382	int i;
8f03dea5 MJ	383
c6a1e615 PM	384	proto_array = kmalloc(MAX_NF_CT_PROTO *
	385	sizeof(struct nf_conntrack_l4proto *),
	386	GFP_KERNEL);
8f03dea5 MJ	387	if (proto_array == NULL) {
8f03dea5 MJ	388	ret = -ENOMEM;
b19caa0c	389	goto out_unlock;
8f03dea5	390	}
c6a1e615	391
8f03dea5	392	for (i = 0; i < MAX_NF_CT_PROTO; i++)
c5d277d2	393	RCU_INIT_POINTER(proto_array[i], &nf_conntrack_l4proto_generic);
d817d29d ED	394
	395	/* Before making proto_array visible to lockless readers,
	396	* we must make sure its content is committed to memory.
	397	*/
	398	smp_wmb();
	399
c6a1e615	400	nf_ct_protos[l4proto->l3proto] = proto_array;
0e60ebe0 ED	401	} else if (rcu_dereference_protected(
	402	nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
	403	lockdep_is_held(&nf_ct_proto_mutex)
	404	) != &nf_conntrack_l4proto_generic) {
c6a1e615 PM	405	ret = -EBUSY;
c6a1e615 PM	406	goto out_unlock;
8f03dea5 MJ	407	}
8f03dea5 MJ	408
d0dba725 HE	409	l4proto->nla_size = 0;
	410	if (l4proto->nlattr_size)
	411	l4proto->nla_size += l4proto->nlattr_size();
	412	if (l4proto->nlattr_tuple_size)
	413	l4proto->nla_size += 3 * l4proto->nlattr_tuple_size();
	414
c6a1e615 PM	415	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
c6a1e615 PM	416	l4proto);
8f03dea5	417	out_unlock:
b19caa0c	418	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5 MJ	419	return ret;
8f03dea5 MJ	420	}
c296bb4d	421	EXPORT_SYMBOL_GPL(nf_ct_l4proto_register);
8f03dea5	422
c296bb4d	423	int nf_ct_l4proto_pernet_register(struct net *net,
2c352f44	424	struct nf_conntrack_l4proto *l4proto)
8f03dea5	425	{
2c352f44	426	int ret = 0;
fa34fff5	427	struct nf_proto_net *pn = NULL;
2c352f44	428
fa0f61f0	429	if (l4proto->init_net) {
f1caad27	430	ret = l4proto->init_net(net, l4proto->l3proto);
fa0f61f0	431	if (ret < 0)
fa34fff5	432	goto out;
fa0f61f0	433	}
678d6675	434
fa34fff5 G	435	pn = nf_ct_l4proto_net(net, l4proto);
	436	if (pn == NULL)
	437	goto out;
	438
	439	ret = nf_ct_l4proto_register_sysctl(net, pn, l4proto);
2c352f44	440	if (ret < 0)
fa34fff5	441	goto out;
2c352f44	442
fa34fff5 G	443	pn->users++;
fa34fff5 G	444	out:
fa0f61f0	445	return ret;
2c352f44	446	}
c296bb4d	447	EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_register);
2c352f44	448
c296bb4d	449	void nf_ct_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
2c352f44	450	{
fe3eb20c	451	BUG_ON(l4proto->l3proto >= PF_MAX);
ae5718fb	452
b19caa0c	453	mutex_lock(&nf_ct_proto_mutex);
0e60ebe0 ED	454	BUG_ON(rcu_dereference_protected(
	455	nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
	456	lockdep_is_held(&nf_ct_proto_mutex)
	457	) != l4proto);
923f4902 PM	458	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
923f4902 PM	459	&nf_conntrack_l4proto_generic);
b19caa0c	460	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	461
0661cca9	462	synchronize_rcu();
2c352f44	463	}
c296bb4d	464	EXPORT_SYMBOL_GPL(nf_ct_l4proto_unregister);
d62f9ed4	465
c296bb4d	466	void nf_ct_l4proto_pernet_unregister(struct net *net,
2c352f44 G	467	struct nf_conntrack_l4proto *l4proto)
2c352f44 G	468	{
fa34fff5 G	469	struct nf_proto_net *pn = NULL;
fa34fff5 G	470
fa34fff5 G	471	pn = nf_ct_l4proto_net(net, l4proto);
	472	if (pn == NULL)
	473	return;
	474
	475	pn->users--;
	476	nf_ct_l4proto_unregister_sysctl(net, pn, l4proto);
	477
8f03dea5	478	/* Remove all contrack entries for this protocol */
c655bc68	479	nf_ct_iterate_cleanup(net, kill_l4proto, l4proto, 0, 0);
8f03dea5	480	}
c296bb4d	481	EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_unregister);
ac5357eb	482
04d87001	483	int nf_conntrack_proto_pernet_init(struct net *net)
ac5357eb	484	{
ac5357eb	485	int err;
fa34fff5 G	486	struct nf_proto_net *pn = nf_ct_l4proto_net(net,
	487	&nf_conntrack_l4proto_generic);
	488
f1caad27 G	489	err = nf_conntrack_l4proto_generic.init_net(net,
f1caad27 G	490	nf_conntrack_l4proto_generic.l3proto);
15f585bd G	491	if (err < 0)
	492	return err;
	493	err = nf_ct_l4proto_register_sysctl(net,
fa34fff5	494	pn,
15f585bd	495	&nf_conntrack_l4proto_generic);
ac5357eb PM	496	if (err < 0)
	497	return err;
	498
fa34fff5	499	pn->users++;
ac5357eb PM	500	return 0;
	501	}
	502
04d87001	503	void nf_conntrack_proto_pernet_fini(struct net *net)
ac5357eb	504	{
fa34fff5 G	505	struct nf_proto_net *pn = nf_ct_l4proto_net(net,
	506	&nf_conntrack_l4proto_generic);
	507
	508	pn->users--;
15f585bd	509	nf_ct_l4proto_unregister_sysctl(net,
fa34fff5	510	pn,
15f585bd	511	&nf_conntrack_l4proto_generic);
04d87001 G	512	}
	513
	514	int nf_conntrack_proto_init(void)
	515	{
	516	unsigned int i;
	517	for (i = 0; i < AF_MAX; i++)
	518	rcu_assign_pointer(nf_ct_l3protos[i],
	519	&nf_conntrack_l3proto_generic);
	520	return 0;
	521	}
	522
	523	void nf_conntrack_proto_fini(void)
	524	{
	525	unsigned int i;
	526	/* free l3proto protocol tables */
	527	for (i = 0; i < PF_MAX; i++)
	528	kfree(nf_ct_protos[i]);
ac5357eb	529	}