[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
}

static int
nf_conntrack_l3proto_register_net(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;

}

int nf_conntrack_l3proto_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;
	}

	ret = nf_ct_l3proto_register_sysctl(net, proto);
	if (ret < 0)
		return ret;

	if (net == &init_net) {
		ret = nf_conntrack_l3proto_register_net(proto);
		if (ret < 0)
			nf_ct_l3proto_unregister_sysctl(net, proto);
	}

	return ret;
}
EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_register);

static void
nf_conntrack_l3proto_unregister_net(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();
}

void nf_conntrack_l3proto_unregister(struct net *net,
				     struct nf_conntrack_l3proto *proto)
{
	if (net == &init_net)
		nf_conntrack_l3proto_unregister_net(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_conntrack_l3proto_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 */
static int
nf_conntrack_l4proto_register_net(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;
}

int nf_conntrack_l4proto_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;

	if (net == &init_net) {
		ret = nf_conntrack_l4proto_register_net(l4proto);
		if (ret < 0) {
			nf_ct_l4proto_unregister_sysctl(net, pn, l4proto);
			goto out;
		}
	}

	pn->users++;
out:
	return ret;
}
EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_register);

static void
nf_conntrack_l4proto_unregister_net(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();
}

void nf_conntrack_l4proto_unregister(struct net *net,
				     struct nf_conntrack_l4proto *l4proto)
{
	struct nf_proto_net *pn = NULL;

	if (net == &init_net)
		nf_conntrack_l4proto_unregister_net(l4proto);

	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_conntrack_l4proto_unregister);

int nf_conntrack_proto_init(struct net *net)
{
	unsigned int i;
	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;

	if (net == &init_net) {
		for (i = 0; i < AF_MAX; i++)
			rcu_assign_pointer(nf_ct_l3protos[i],
					   &nf_conntrack_l3proto_generic);
	}

	pn->users++;
	return 0;
}

void nf_conntrack_proto_fini(struct net *net)
{
	unsigned int i;
	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);
	if (net == &init_net) {
		/* 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
524a53e5 G	215	static int
524a53e5 G	216	nf_conntrack_l3proto_register_net(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 MJ	244	}
8f03dea5 MJ	245
524a53e5 G	246	int nf_conntrack_l3proto_register(struct net *net,
524a53e5 G	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
fa0f61f0	257	ret = nf_ct_l3proto_register_sysctl(net, proto);
524a53e5 G	258	if (ret < 0)
	259	return ret;
	260
fa0f61f0 G	261	if (net == &init_net) {
fa0f61f0 G	262	ret = nf_conntrack_l3proto_register_net(proto);
524a53e5	263	if (ret < 0)
fa0f61f0	264	nf_ct_l3proto_unregister_sysctl(net, proto);
524a53e5	265	}
fa0f61f0 G	266
fa0f61f0 G	267	return ret;
524a53e5 G	268	}
524a53e5 G	269	EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_register);
678d6675	270
524a53e5 G	271	static void
	272	nf_conntrack_l3proto_unregister_net(struct nf_conntrack_l3proto *proto)
	273	{
fe3eb20c	274	BUG_ON(proto->l3proto >= AF_MAX);
ae5718fb	275
b19caa0c	276	mutex_lock(&nf_ct_proto_mutex);
0e60ebe0 ED	277	BUG_ON(rcu_dereference_protected(nf_ct_l3protos[proto->l3proto],
	278	lockdep_is_held(&nf_ct_proto_mutex)
	279	) != proto);
923f4902 PM	280	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto],
923f4902 PM	281	&nf_conntrack_l3proto_generic);
b19caa0c	282	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	283
0661cca9	284	synchronize_rcu();
524a53e5 G	285	}
	286
	287	void nf_conntrack_l3proto_unregister(struct net *net,
	288	struct nf_conntrack_l3proto *proto)
	289	{
	290	if (net == &init_net)
	291	nf_conntrack_l3proto_unregister_net(proto);
	292
	293	nf_ct_l3proto_unregister_sysctl(net, proto);
d62f9ed4	294
8f03dea5	295	/* Remove all contrack entries for this protocol */
524a53e5	296	nf_ct_iterate_cleanup(net, kill_l3proto, proto);
8f03dea5	297	}
13b18339	298	EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_unregister);
8f03dea5	299
2c352f44 G	300	static struct nf_proto_net nf_ct_l4proto_net(struct net net,
	301	struct nf_conntrack_l4proto *l4proto)
	302	{
08911475 PNA	303	if (l4proto->get_net_proto) {
	304	/* statically built-in protocols use static per-net */
	305	return l4proto->get_net_proto(net);
	306	} else if (l4proto->net_id) {
	307	/* ... and loadable protocols use dynamic per-net */
	308	return net_generic(net, *l4proto->net_id);
15f585bd G	309	}
15f585bd G	310	return NULL;
2c352f44 G	311	}
	312
	313	static
	314	int nf_ct_l4proto_register_sysctl(struct net *net,
fa34fff5	315	struct nf_proto_net *pn,
2c352f44	316	struct nf_conntrack_l4proto *l4proto)
d62f9ed4 PM	317	{
	318	int err = 0;
	319
	320	#ifdef CONFIG_SYSCTL
2c352f44 G	321	if (pn->ctl_table != NULL) {
	322	err = nf_ct_register_sysctl(net,
	323	&pn->ctl_table_header,
f99e8f71	324	"net/netfilter",
fa34fff5	325	pn->ctl_table);
2c352f44 G	326	if (err < 0) {
	327	if (!pn->users) {
	328	kfree(pn->ctl_table);
	329	pn->ctl_table = NULL;
	330	}
2c352f44	331	}
d62f9ed4	332	}
a999e683	333	#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
2c352f44	334	if (l4proto->l3proto != AF_INET6 && pn->ctl_compat_table != NULL) {
12c26df3 G	335	if (err < 0) {
	336	nf_ct_kfree_compat_sysctl_table(pn);
	337	goto out;
	338	}
2c352f44 G	339	err = nf_ct_register_sysctl(net,
2c352f44 G	340	&pn->ctl_compat_header,
f99e8f71	341	"net/ipv4/netfilter",
fa34fff5	342	pn->ctl_compat_table);
a999e683 PM	343	if (err == 0)
a999e683 PM	344	goto out;
2c352f44	345
f28997e2	346	nf_ct_kfree_compat_sysctl_table(pn);
2c352f44 G	347	nf_ct_unregister_sysctl(&pn->ctl_table_header,
2c352f44 G	348	&pn->ctl_table,
fa34fff5	349	pn->users);
a999e683	350	}
a999e683	351	out:
12c26df3	352	#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
933a41e7	353	#endif /* CONFIG_SYSCTL */
d62f9ed4 PM	354	return err;
	355	}
	356
2c352f44 G	357	static
2c352f44 G	358	void nf_ct_l4proto_unregister_sysctl(struct net *net,
fa34fff5	359	struct nf_proto_net *pn,
2c352f44	360	struct nf_conntrack_l4proto *l4proto)
d62f9ed4 PM	361	{
d62f9ed4 PM	362	#ifdef CONFIG_SYSCTL
2c352f44 G	363	if (pn->ctl_table_header != NULL)
	364	nf_ct_unregister_sysctl(&pn->ctl_table_header,
	365	&pn->ctl_table,
fa34fff5	366	pn->users);
2c352f44	367
a999e683	368	#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
2c352f44 G	369	if (l4proto->l3proto != AF_INET6 && pn->ctl_compat_header != NULL)
	370	nf_ct_unregister_sysctl(&pn->ctl_compat_header,
	371	&pn->ctl_compat_table,
fa34fff5	372	0);
a999e683	373	#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
933a41e7	374	#endif /* CONFIG_SYSCTL */
d62f9ed4 PM	375	}
d62f9ed4 PM	376
8f03dea5 MJ	377	/* FIXME: Allow NULL functions and sub in pointers to generic for
8f03dea5 MJ	378	them. --RR */
2c352f44 G	379	static int
2c352f44 G	380	nf_conntrack_l4proto_register_net(struct nf_conntrack_l4proto *l4proto)
8f03dea5 MJ	381	{
	382	int ret = 0;
	383
0661cca9 PM	384	if (l4proto->l3proto >= PF_MAX)
0661cca9 PM	385	return -EBUSY;
ae5718fb	386
d0dba725 HE	387	if ((l4proto->to_nlattr && !l4proto->nlattr_size)
	388	\|\| (l4proto->tuple_to_nlattr && !l4proto->nlattr_tuple_size))
	389	return -EINVAL;
	390
b19caa0c	391	mutex_lock(&nf_ct_proto_mutex);
c6a1e615	392	if (!nf_ct_protos[l4proto->l3proto]) {
8f03dea5	393	/* l3proto may be loaded latter. */
c5d277d2	394	struct nf_conntrack_l4proto __rcu **proto_array;
8f03dea5 MJ	395	int i;
8f03dea5 MJ	396
c6a1e615 PM	397	proto_array = kmalloc(MAX_NF_CT_PROTO *
	398	sizeof(struct nf_conntrack_l4proto *),
	399	GFP_KERNEL);
8f03dea5 MJ	400	if (proto_array == NULL) {
8f03dea5 MJ	401	ret = -ENOMEM;
b19caa0c	402	goto out_unlock;
8f03dea5	403	}
c6a1e615	404
8f03dea5	405	for (i = 0; i < MAX_NF_CT_PROTO; i++)
c5d277d2	406	RCU_INIT_POINTER(proto_array[i], &nf_conntrack_l4proto_generic);
d817d29d ED	407
	408	/* Before making proto_array visible to lockless readers,
	409	* we must make sure its content is committed to memory.
	410	*/
	411	smp_wmb();
	412
c6a1e615	413	nf_ct_protos[l4proto->l3proto] = proto_array;
0e60ebe0 ED	414	} else if (rcu_dereference_protected(
	415	nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
	416	lockdep_is_held(&nf_ct_proto_mutex)
	417	) != &nf_conntrack_l4proto_generic) {
c6a1e615 PM	418	ret = -EBUSY;
c6a1e615 PM	419	goto out_unlock;
8f03dea5 MJ	420	}
8f03dea5 MJ	421
d0dba725 HE	422	l4proto->nla_size = 0;
	423	if (l4proto->nlattr_size)
	424	l4proto->nla_size += l4proto->nlattr_size();
	425	if (l4proto->nlattr_tuple_size)
	426	l4proto->nla_size += 3 * l4proto->nlattr_tuple_size();
	427
c6a1e615 PM	428	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
c6a1e615 PM	429	l4proto);
8f03dea5	430	out_unlock:
b19caa0c	431	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5 MJ	432	return ret;
	433	}
	434
2c352f44 G	435	int nf_conntrack_l4proto_register(struct net *net,
2c352f44 G	436	struct nf_conntrack_l4proto *l4proto)
8f03dea5	437	{
2c352f44	438	int ret = 0;
fa34fff5	439	struct nf_proto_net *pn = NULL;
2c352f44	440
fa0f61f0	441	if (l4proto->init_net) {
f1caad27	442	ret = l4proto->init_net(net, l4proto->l3proto);
fa0f61f0	443	if (ret < 0)
fa34fff5	444	goto out;
fa0f61f0	445	}
678d6675	446
fa34fff5 G	447	pn = nf_ct_l4proto_net(net, l4proto);
	448	if (pn == NULL)
	449	goto out;
	450
	451	ret = nf_ct_l4proto_register_sysctl(net, pn, l4proto);
2c352f44	452	if (ret < 0)
fa34fff5	453	goto out;
2c352f44	454
fa0f61f0 G	455	if (net == &init_net) {
fa0f61f0 G	456	ret = nf_conntrack_l4proto_register_net(l4proto);
fa34fff5 G	457	if (ret < 0) {
	458	nf_ct_l4proto_unregister_sysctl(net, pn, l4proto);
	459	goto out;
	460	}
fa0f61f0 G	461	}
fa0f61f0 G	462
fa34fff5 G	463	pn->users++;
fa34fff5 G	464	out:
fa0f61f0	465	return ret;
2c352f44 G	466	}
	467	EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_register);
	468
	469	static void
	470	nf_conntrack_l4proto_unregister_net(struct nf_conntrack_l4proto *l4proto)
	471	{
fe3eb20c	472	BUG_ON(l4proto->l3proto >= PF_MAX);
ae5718fb	473
b19caa0c	474	mutex_lock(&nf_ct_proto_mutex);
0e60ebe0 ED	475	BUG_ON(rcu_dereference_protected(
	476	nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
	477	lockdep_is_held(&nf_ct_proto_mutex)
	478	) != l4proto);
923f4902 PM	479	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
923f4902 PM	480	&nf_conntrack_l4proto_generic);
b19caa0c	481	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	482
0661cca9	483	synchronize_rcu();
2c352f44	484	}
d62f9ed4	485
2c352f44 G	486	void nf_conntrack_l4proto_unregister(struct net *net,
	487	struct nf_conntrack_l4proto *l4proto)
	488	{
fa34fff5 G	489	struct nf_proto_net *pn = NULL;
fa34fff5 G	490
2c352f44 G	491	if (net == &init_net)
	492	nf_conntrack_l4proto_unregister_net(l4proto);
	493
fa34fff5 G	494	pn = nf_ct_l4proto_net(net, l4proto);
	495	if (pn == NULL)
	496	return;
	497
	498	pn->users--;
	499	nf_ct_l4proto_unregister_sysctl(net, pn, l4proto);
	500
8f03dea5	501	/* Remove all contrack entries for this protocol */
2c352f44	502	nf_ct_iterate_cleanup(net, kill_l4proto, l4proto);
8f03dea5	503	}
13b18339	504	EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_unregister);
ac5357eb	505
15f585bd	506	int nf_conntrack_proto_init(struct net *net)
ac5357eb PM	507	{
	508	unsigned int i;
	509	int err;
fa34fff5 G	510	struct nf_proto_net *pn = nf_ct_l4proto_net(net,
	511	&nf_conntrack_l4proto_generic);
	512
f1caad27 G	513	err = nf_conntrack_l4proto_generic.init_net(net,
f1caad27 G	514	nf_conntrack_l4proto_generic.l3proto);
15f585bd G	515	if (err < 0)
	516	return err;
	517	err = nf_ct_l4proto_register_sysctl(net,
fa34fff5	518	pn,
15f585bd	519	&nf_conntrack_l4proto_generic);
ac5357eb PM	520	if (err < 0)
	521	return err;
	522
15f585bd G	523	if (net == &init_net) {
	524	for (i = 0; i < AF_MAX; i++)
	525	rcu_assign_pointer(nf_ct_l3protos[i],
	526	&nf_conntrack_l3proto_generic);
	527	}
fa34fff5 G	528
fa34fff5 G	529	pn->users++;
ac5357eb PM	530	return 0;
	531	}
	532
15f585bd	533	void nf_conntrack_proto_fini(struct net *net)
ac5357eb PM	534	{
ac5357eb PM	535	unsigned int i;
fa34fff5 G	536	struct nf_proto_net *pn = nf_ct_l4proto_net(net,
	537	&nf_conntrack_l4proto_generic);
	538
	539	pn->users--;
15f585bd	540	nf_ct_l4proto_unregister_sysctl(net,
fa34fff5	541	pn,
15f585bd G	542	&nf_conntrack_l4proto_generic);
	543	if (net == &init_net) {
	544	/* free l3proto protocol tables */
	545	for (i = 0; i < PF_MAX; i++)
	546	kfree(nf_ct_protos[i]);
	547	}
ac5357eb	548	}