[mirror_ubuntu-zesty-kernel.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);

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);

int nf_ct_netns_get(struct net *net, u8 nfproto)
{
	const struct nf_conntrack_l3proto *l3proto;
	int ret;

	might_sleep();

	ret = nf_ct_l3proto_try_module_get(nfproto);
	if (ret < 0)
		return ret;

	/* we already have a reference, can't fail */
	rcu_read_lock();
	l3proto = __nf_ct_l3proto_find(nfproto);
	rcu_read_unlock();

	if (!l3proto->net_ns_get)
		return 0;

	ret = l3proto->net_ns_get(net);
	if (ret < 0)
		nf_ct_l3proto_module_put(nfproto);

	return ret;
}
EXPORT_SYMBOL_GPL(nf_ct_netns_get);

void nf_ct_netns_put(struct net *net, u8 nfproto)
{
	const struct nf_conntrack_l3proto *l3proto;

	might_sleep();

	/* same as nf_conntrack_netns_get(), reference assumed */
	rcu_read_lock();
	l3proto = __nf_ct_l3proto_find(nfproto);
	rcu_read_unlock();

	if (WARN_ON(!l3proto))
		return;

	if (l3proto->net_ns_put)
		l3proto->net_ns_put(net);

	nf_ct_l3proto_module_put(nfproto);
}
EXPORT_SYMBOL_GPL(nf_ct_netns_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;
}

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);

#ifdef CONFIG_SYSCTL
extern unsigned int nf_conntrack_default_on;

int nf_ct_l3proto_pernet_register(struct net *net,
				  struct nf_conntrack_l3proto *proto)
{
	if (nf_conntrack_default_on == 0)
		return 0;

	return proto->net_ns_get ? proto->net_ns_get(net) : 0;
}
EXPORT_SYMBOL_GPL(nf_ct_l3proto_pernet_register);
#endif

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_conntrack_default_on *might* have registered hooks.
	 * ->net_ns_put must cope with more puts() than get(), i.e.
	 * if nf_conntrack_default_on was 0 at time of
	 * nf_ct_l3proto_pernet_register invocation this net_ns_put()
	 * should be a noop.
	 */
	if (proto->net_ns_put)
		proto->net_ns_put(net);

	/* 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;
			}
		}
	}
#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);
#endif /* CONFIG_SYSCTL */
}

/* FIXME: Allow NULL functions and sub in pointers to generic for
   them. --RR */
int nf_ct_l4proto_register_one(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_one);

int nf_ct_l4proto_pernet_register_one(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_one);

void nf_ct_l4proto_unregister_one(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_one);

void nf_ct_l4proto_pernet_unregister_one(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_one);

int nf_ct_l4proto_register(struct nf_conntrack_l4proto *l4proto[],
			   unsigned int num_proto)
{
	int ret = -EINVAL, ver;
	unsigned int i;

	for (i = 0; i < num_proto; i++) {
		ret = nf_ct_l4proto_register_one(l4proto[i]);
		if (ret < 0)
			break;
	}
	if (i != num_proto) {
		ver = l4proto[i]->l3proto == PF_INET6 ? 6 : 4;
		pr_err("nf_conntrack_ipv%d: can't register %s%d proto.\n",
		       ver, l4proto[i]->name, ver);
		nf_ct_l4proto_unregister(l4proto, i);
	}
	return ret;
}
EXPORT_SYMBOL_GPL(nf_ct_l4proto_register);

int nf_ct_l4proto_pernet_register(struct net *net,
				  struct nf_conntrack_l4proto *l4proto[],
				  unsigned int num_proto)
{
	int ret = -EINVAL;
	unsigned int i;

	for (i = 0; i < num_proto; i++) {
		ret = nf_ct_l4proto_pernet_register_one(net, l4proto[i]);
		if (ret < 0)
			break;
	}
	if (i != num_proto) {
		pr_err("nf_conntrack_%s%d: pernet registration failed\n",
		       l4proto[i]->name,
		       l4proto[i]->l3proto == PF_INET6 ? 6 : 4);
		nf_ct_l4proto_pernet_unregister(net, l4proto, i);
	}
	return ret;
}
EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_register);

void nf_ct_l4proto_unregister(struct nf_conntrack_l4proto *l4proto[],
			      unsigned int num_proto)
{
	while (num_proto-- != 0)
		nf_ct_l4proto_unregister_one(l4proto[num_proto]);
}
EXPORT_SYMBOL_GPL(nf_ct_l4proto_unregister);

void nf_ct_l4proto_pernet_unregister(struct net *net,
				     struct nf_conntrack_l4proto *l4proto[],
				     unsigned int num_proto)
{
	while (num_proto-- != 0)
		nf_ct_l4proto_pernet_unregister_one(net, l4proto[num_proto]);
}
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	94
8f03dea5 MJ	95	int
	96	nf_ct_l3proto_try_module_get(unsigned short l3proto)
	97	{
	98	int ret;
	99	struct nf_conntrack_l3proto *p;
	100
	101	retry: p = nf_ct_l3proto_find_get(l3proto);
605dcad6	102	if (p == &nf_conntrack_l3proto_generic) {
8f03dea5 MJ	103	ret = request_module("nf_conntrack-%d", l3proto);
	104	if (!ret)
	105	goto retry;
	106
	107	return -EPROTOTYPE;
	108	}
	109
	110	return 0;
	111	}
13b18339	112	EXPORT_SYMBOL_GPL(nf_ct_l3proto_try_module_get);
8f03dea5 MJ	113
	114	void nf_ct_l3proto_module_put(unsigned short l3proto)
	115	{
	116	struct nf_conntrack_l3proto *p;
	117
3b254c54 PM	118	/* rcu_read_lock not necessary since the caller holds a reference, but
	119	* taken anyways to avoid lockdep warnings in __nf_ct_l3proto_find()
	120	*/
	121	rcu_read_lock();
8f03dea5	122	p = __nf_ct_l3proto_find(l3proto);
8f03dea5	123	module_put(p->me);
3b254c54	124	rcu_read_unlock();
8f03dea5	125	}
13b18339	126	EXPORT_SYMBOL_GPL(nf_ct_l3proto_module_put);
8f03dea5	127
ecb2421b FW	128	int nf_ct_netns_get(struct net *net, u8 nfproto)
ecb2421b FW	129	{
0c66dc1e FW	130	const struct nf_conntrack_l3proto *l3proto;
	131	int ret;
	132
	133	might_sleep();
	134
	135	ret = nf_ct_l3proto_try_module_get(nfproto);
	136	if (ret < 0)
	137	return ret;
	138
	139	/* we already have a reference, can't fail */
	140	rcu_read_lock();
	141	l3proto = __nf_ct_l3proto_find(nfproto);
	142	rcu_read_unlock();
	143
	144	if (!l3proto->net_ns_get)
	145	return 0;
	146
	147	ret = l3proto->net_ns_get(net);
	148	if (ret < 0)
	149	nf_ct_l3proto_module_put(nfproto);
	150
	151	return ret;
ecb2421b FW	152	}
	153	EXPORT_SYMBOL_GPL(nf_ct_netns_get);
	154
	155	void nf_ct_netns_put(struct net *net, u8 nfproto)
	156	{
0c66dc1e FW	157	const struct nf_conntrack_l3proto *l3proto;
	158
	159	might_sleep();
	160
	161	/* same as nf_conntrack_netns_get(), reference assumed */
	162	rcu_read_lock();
	163	l3proto = __nf_ct_l3proto_find(nfproto);
	164	rcu_read_unlock();
	165
	166	if (WARN_ON(!l3proto))
	167	return;
	168
	169	if (l3proto->net_ns_put)
	170	l3proto->net_ns_put(net);
	171
ecb2421b FW	172	nf_ct_l3proto_module_put(nfproto);
	173	}
	174	EXPORT_SYMBOL_GPL(nf_ct_netns_put);
	175
c1ebd7df PNA	176	struct nf_conntrack_l4proto *
	177	nf_ct_l4proto_find_get(u_int16_t l3num, u_int8_t l4num)
	178	{
	179	struct nf_conntrack_l4proto *p;
	180
	181	rcu_read_lock();
	182	p = __nf_ct_l4proto_find(l3num, l4num);
	183	if (!try_module_get(p->me))
	184	p = &nf_conntrack_l4proto_generic;
	185	rcu_read_unlock();
	186
	187	return p;
	188	}
	189	EXPORT_SYMBOL_GPL(nf_ct_l4proto_find_get);
	190
	191	void nf_ct_l4proto_put(struct nf_conntrack_l4proto *p)
	192	{
	193	module_put(p->me);
	194	}
	195	EXPORT_SYMBOL_GPL(nf_ct_l4proto_put);
	196
8f03dea5 MJ	197	static int kill_l3proto(struct nf_conn i, void data)
8f03dea5 MJ	198	{
5e8fbe2a	199	return nf_ct_l3num(i) == ((struct nf_conntrack_l3proto *)data)->l3proto;
8f03dea5 MJ	200	}
8f03dea5 MJ	201
605dcad6	202	static int kill_l4proto(struct nf_conn i, void data)
8f03dea5	203	{
605dcad6 MJ	204	struct nf_conntrack_l4proto *l4proto;
605dcad6 MJ	205	l4proto = (struct nf_conntrack_l4proto *)data;
5e8fbe2a PM	206	return nf_ct_protonum(i) == l4proto->l4proto &&
5e8fbe2a PM	207	nf_ct_l3num(i) == l4proto->l3proto;
8f03dea5 MJ	208	}
8f03dea5 MJ	209
6330750d	210	int nf_ct_l3proto_register(struct nf_conntrack_l3proto *proto)
8f03dea5 MJ	211	{
8f03dea5 MJ	212	int ret = 0;
0e60ebe0	213	struct nf_conntrack_l3proto *old;
8f03dea5	214
0661cca9 PM	215	if (proto->l3proto >= AF_MAX)
0661cca9 PM	216	return -EBUSY;
ae5718fb	217
d0dba725 HE	218	if (proto->tuple_to_nlattr && !proto->nlattr_tuple_size)
	219	return -EINVAL;
	220
b19caa0c	221	mutex_lock(&nf_ct_proto_mutex);
0e60ebe0 ED	222	old = rcu_dereference_protected(nf_ct_l3protos[proto->l3proto],
	223	lockdep_is_held(&nf_ct_proto_mutex));
	224	if (old != &nf_conntrack_l3proto_generic) {
8f03dea5	225	ret = -EBUSY;
ae5718fb	226	goto out_unlock;
8f03dea5	227	}
d62f9ed4	228
d0dba725 HE	229	if (proto->nlattr_tuple_size)
	230	proto->nla_size = 3 * proto->nlattr_tuple_size();
	231
0661cca9	232	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto], proto);
8f03dea5	233
ae5718fb	234	out_unlock:
b19caa0c	235	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	236	return ret;
524a53e5	237
8f03dea5	238	}
6330750d	239	EXPORT_SYMBOL_GPL(nf_ct_l3proto_register);
8f03dea5	240
481fa373 FW	241	#ifdef CONFIG_SYSCTL
	242	extern unsigned int nf_conntrack_default_on;
	243
6330750d	244	int nf_ct_l3proto_pernet_register(struct net *net,
524a53e5	245	struct nf_conntrack_l3proto *proto)
8f03dea5	246	{
481fa373 FW	247	if (nf_conntrack_default_on == 0)
	248	return 0;
	249
	250	return proto->net_ns_get ? proto->net_ns_get(net) : 0;
524a53e5	251	}
6330750d	252	EXPORT_SYMBOL_GPL(nf_ct_l3proto_pernet_register);
481fa373	253	#endif
678d6675	254
6330750d	255	void nf_ct_l3proto_unregister(struct nf_conntrack_l3proto *proto)
524a53e5	256	{
fe3eb20c	257	BUG_ON(proto->l3proto >= AF_MAX);
ae5718fb	258
b19caa0c	259	mutex_lock(&nf_ct_proto_mutex);
0e60ebe0 ED	260	BUG_ON(rcu_dereference_protected(nf_ct_l3protos[proto->l3proto],
	261	lockdep_is_held(&nf_ct_proto_mutex)
	262	) != proto);
923f4902 PM	263	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto],
923f4902 PM	264	&nf_conntrack_l3proto_generic);
b19caa0c	265	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	266
0661cca9	267	synchronize_rcu();
524a53e5	268	}
6330750d	269	EXPORT_SYMBOL_GPL(nf_ct_l3proto_unregister);
524a53e5	270
6330750d	271	void nf_ct_l3proto_pernet_unregister(struct net *net,
524a53e5 G	272	struct nf_conntrack_l3proto *proto)
524a53e5 G	273	{
481fa373 FW	274	/*
	275	* nf_conntrack_default_on might have registered hooks.
	276	* ->net_ns_put must cope with more puts() than get(), i.e.
	277	* if nf_conntrack_default_on was 0 at time of
	278	* nf_ct_l3proto_pernet_register invocation this net_ns_put()
	279	* should be a noop.
	280	*/
	281	if (proto->net_ns_put)
	282	proto->net_ns_put(net);
	283
8f03dea5	284	/* Remove all contrack entries for this protocol */
c655bc68	285	nf_ct_iterate_cleanup(net, kill_l3proto, proto, 0, 0);
8f03dea5	286	}
6330750d	287	EXPORT_SYMBOL_GPL(nf_ct_l3proto_pernet_unregister);
8f03dea5	288
2c352f44 G	289	static struct nf_proto_net nf_ct_l4proto_net(struct net net,
	290	struct nf_conntrack_l4proto *l4proto)
	291	{
08911475 PNA	292	if (l4proto->get_net_proto) {
	293	/* statically built-in protocols use static per-net */
	294	return l4proto->get_net_proto(net);
	295	} else if (l4proto->net_id) {
	296	/* ... and loadable protocols use dynamic per-net */
	297	return net_generic(net, *l4proto->net_id);
15f585bd G	298	}
15f585bd G	299	return NULL;
2c352f44 G	300	}
	301
	302	static
	303	int nf_ct_l4proto_register_sysctl(struct net *net,
fa34fff5	304	struct nf_proto_net *pn,
2c352f44	305	struct nf_conntrack_l4proto *l4proto)
d62f9ed4 PM	306	{
	307	int err = 0;
	308
	309	#ifdef CONFIG_SYSCTL
2c352f44 G	310	if (pn->ctl_table != NULL) {
	311	err = nf_ct_register_sysctl(net,
	312	&pn->ctl_table_header,
f99e8f71	313	"net/netfilter",
fa34fff5	314	pn->ctl_table);
2c352f44 G	315	if (err < 0) {
	316	if (!pn->users) {
	317	kfree(pn->ctl_table);
	318	pn->ctl_table = NULL;
	319	}
2c352f44	320	}
d62f9ed4	321	}
933a41e7	322	#endif /* CONFIG_SYSCTL */
d62f9ed4 PM	323	return err;
	324	}
	325
2c352f44 G	326	static
2c352f44 G	327	void nf_ct_l4proto_unregister_sysctl(struct net *net,
fa34fff5	328	struct nf_proto_net *pn,
2c352f44	329	struct nf_conntrack_l4proto *l4proto)
d62f9ed4 PM	330	{
d62f9ed4 PM	331	#ifdef CONFIG_SYSCTL
2c352f44 G	332	if (pn->ctl_table_header != NULL)
	333	nf_ct_unregister_sysctl(&pn->ctl_table_header,
	334	&pn->ctl_table,
fa34fff5	335	pn->users);
933a41e7	336	#endif /* CONFIG_SYSCTL */
d62f9ed4 PM	337	}
d62f9ed4 PM	338
8f03dea5 MJ	339	/* FIXME: Allow NULL functions and sub in pointers to generic for
8f03dea5 MJ	340	them. --RR */
0e54d217	341	int nf_ct_l4proto_register_one(struct nf_conntrack_l4proto *l4proto)
8f03dea5 MJ	342	{
	343	int ret = 0;
	344
0661cca9 PM	345	if (l4proto->l3proto >= PF_MAX)
0661cca9 PM	346	return -EBUSY;
ae5718fb	347
0e54d217 DC	348	if ((l4proto->to_nlattr && !l4proto->nlattr_size) \|\|
0e54d217 DC	349	(l4proto->tuple_to_nlattr && !l4proto->nlattr_tuple_size))
d0dba725 HE	350	return -EINVAL;
d0dba725 HE	351
b19caa0c	352	mutex_lock(&nf_ct_proto_mutex);
c6a1e615	353	if (!nf_ct_protos[l4proto->l3proto]) {
8f03dea5	354	/* l3proto may be loaded latter. */
c5d277d2	355	struct nf_conntrack_l4proto __rcu **proto_array;
8f03dea5 MJ	356	int i;
8f03dea5 MJ	357
c6a1e615 PM	358	proto_array = kmalloc(MAX_NF_CT_PROTO *
	359	sizeof(struct nf_conntrack_l4proto *),
	360	GFP_KERNEL);
8f03dea5 MJ	361	if (proto_array == NULL) {
8f03dea5 MJ	362	ret = -ENOMEM;
b19caa0c	363	goto out_unlock;
8f03dea5	364	}
c6a1e615	365
8f03dea5	366	for (i = 0; i < MAX_NF_CT_PROTO; i++)
0e54d217 DC	367	RCU_INIT_POINTER(proto_array[i],
0e54d217 DC	368	&nf_conntrack_l4proto_generic);
d817d29d ED	369
	370	/* Before making proto_array visible to lockless readers,
	371	* we must make sure its content is committed to memory.
	372	*/
	373	smp_wmb();
	374
c6a1e615	375	nf_ct_protos[l4proto->l3proto] = proto_array;
0e60ebe0 ED	376	} else if (rcu_dereference_protected(
	377	nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
	378	lockdep_is_held(&nf_ct_proto_mutex)
	379	) != &nf_conntrack_l4proto_generic) {
c6a1e615 PM	380	ret = -EBUSY;
c6a1e615 PM	381	goto out_unlock;
8f03dea5 MJ	382	}
8f03dea5 MJ	383
d0dba725 HE	384	l4proto->nla_size = 0;
	385	if (l4proto->nlattr_size)
	386	l4proto->nla_size += l4proto->nlattr_size();
	387	if (l4proto->nlattr_tuple_size)
	388	l4proto->nla_size += 3 * l4proto->nlattr_tuple_size();
	389
c6a1e615 PM	390	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
c6a1e615 PM	391	l4proto);
8f03dea5	392	out_unlock:
b19caa0c	393	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5 MJ	394	return ret;
8f03dea5 MJ	395	}
0e54d217	396	EXPORT_SYMBOL_GPL(nf_ct_l4proto_register_one);
8f03dea5	397
0e54d217 DC	398	int nf_ct_l4proto_pernet_register_one(struct net *net,
0e54d217 DC	399	struct nf_conntrack_l4proto *l4proto)
8f03dea5	400	{
2c352f44	401	int ret = 0;
fa34fff5	402	struct nf_proto_net *pn = NULL;
2c352f44	403
fa0f61f0	404	if (l4proto->init_net) {
f1caad27	405	ret = l4proto->init_net(net, l4proto->l3proto);
fa0f61f0	406	if (ret < 0)
fa34fff5	407	goto out;
fa0f61f0	408	}
678d6675	409
fa34fff5 G	410	pn = nf_ct_l4proto_net(net, l4proto);
	411	if (pn == NULL)
	412	goto out;
	413
	414	ret = nf_ct_l4proto_register_sysctl(net, pn, l4proto);
2c352f44	415	if (ret < 0)
fa34fff5	416	goto out;
2c352f44	417
fa34fff5 G	418	pn->users++;
fa34fff5 G	419	out:
fa0f61f0	420	return ret;
2c352f44	421	}
0e54d217	422	EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_register_one);
2c352f44	423
0e54d217	424	void nf_ct_l4proto_unregister_one(struct nf_conntrack_l4proto *l4proto)
2c352f44	425	{
fe3eb20c	426	BUG_ON(l4proto->l3proto >= PF_MAX);
ae5718fb	427
b19caa0c	428	mutex_lock(&nf_ct_proto_mutex);
0e60ebe0 ED	429	BUG_ON(rcu_dereference_protected(
	430	nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
	431	lockdep_is_held(&nf_ct_proto_mutex)
	432	) != l4proto);
923f4902 PM	433	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
923f4902 PM	434	&nf_conntrack_l4proto_generic);
b19caa0c	435	mutex_unlock(&nf_ct_proto_mutex);
8f03dea5	436
0661cca9	437	synchronize_rcu();
2c352f44	438	}
0e54d217	439	EXPORT_SYMBOL_GPL(nf_ct_l4proto_unregister_one);
d62f9ed4	440
0e54d217 DC	441	void nf_ct_l4proto_pernet_unregister_one(struct net *net,
0e54d217 DC	442	struct nf_conntrack_l4proto *l4proto)
2c352f44	443	{
fa34fff5 G	444	struct nf_proto_net *pn = NULL;
fa34fff5 G	445
fa34fff5 G	446	pn = nf_ct_l4proto_net(net, l4proto);
	447	if (pn == NULL)
	448	return;
	449
	450	pn->users--;
	451	nf_ct_l4proto_unregister_sysctl(net, pn, l4proto);
	452
8f03dea5	453	/* Remove all contrack entries for this protocol */
c655bc68	454	nf_ct_iterate_cleanup(net, kill_l4proto, l4proto, 0, 0);
8f03dea5	455	}
0e54d217 DC	456	EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_unregister_one);
	457
	458	int nf_ct_l4proto_register(struct nf_conntrack_l4proto *l4proto[],
	459	unsigned int num_proto)
	460	{
	461	int ret = -EINVAL, ver;
	462	unsigned int i;
	463
	464	for (i = 0; i < num_proto; i++) {
	465	ret = nf_ct_l4proto_register_one(l4proto[i]);
	466	if (ret < 0)
	467	break;
	468	}
	469	if (i != num_proto) {
	470	ver = l4proto[i]->l3proto == PF_INET6 ? 6 : 4;
	471	pr_err("nf_conntrack_ipv%d: can't register %s%d proto.\n",
	472	ver, l4proto[i]->name, ver);
	473	nf_ct_l4proto_unregister(l4proto, i);
	474	}
	475	return ret;
	476	}
	477	EXPORT_SYMBOL_GPL(nf_ct_l4proto_register);
	478
	479	int nf_ct_l4proto_pernet_register(struct net *net,
	480	struct nf_conntrack_l4proto *l4proto[],
	481	unsigned int num_proto)
	482	{
	483	int ret = -EINVAL;
	484	unsigned int i;
	485
	486	for (i = 0; i < num_proto; i++) {
	487	ret = nf_ct_l4proto_pernet_register_one(net, l4proto[i]);
	488	if (ret < 0)
	489	break;
	490	}
	491	if (i != num_proto) {
	492	pr_err("nf_conntrack_%s%d: pernet registration failed\n",
	493	l4proto[i]->name,
	494	l4proto[i]->l3proto == PF_INET6 ? 6 : 4);
	495	nf_ct_l4proto_pernet_unregister(net, l4proto, i);
	496	}
	497	return ret;
	498	}
	499	EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_register);
	500
	501	void nf_ct_l4proto_unregister(struct nf_conntrack_l4proto *l4proto[],
	502	unsigned int num_proto)
	503	{
	504	while (num_proto-- != 0)
	505	nf_ct_l4proto_unregister_one(l4proto[num_proto]);
	506	}
	507	EXPORT_SYMBOL_GPL(nf_ct_l4proto_unregister);
	508
	509	void nf_ct_l4proto_pernet_unregister(struct net *net,
	510	struct nf_conntrack_l4proto *l4proto[],
	511	unsigned int num_proto)
	512	{
	513	while (num_proto-- != 0)
	514	nf_ct_l4proto_pernet_unregister_one(net, l4proto[num_proto]);
	515	}
c296bb4d	516	EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_unregister);
ac5357eb	517
04d87001	518	int nf_conntrack_proto_pernet_init(struct net *net)
ac5357eb	519	{
ac5357eb	520	int err;
fa34fff5 G	521	struct nf_proto_net *pn = nf_ct_l4proto_net(net,
	522	&nf_conntrack_l4proto_generic);
	523
f1caad27 G	524	err = nf_conntrack_l4proto_generic.init_net(net,
f1caad27 G	525	nf_conntrack_l4proto_generic.l3proto);
15f585bd G	526	if (err < 0)
	527	return err;
	528	err = nf_ct_l4proto_register_sysctl(net,
fa34fff5	529	pn,
15f585bd	530	&nf_conntrack_l4proto_generic);
ac5357eb PM	531	if (err < 0)
	532	return err;
	533
fa34fff5	534	pn->users++;
ac5357eb PM	535	return 0;
	536	}
	537
04d87001	538	void nf_conntrack_proto_pernet_fini(struct net *net)
ac5357eb	539	{
fa34fff5 G	540	struct nf_proto_net *pn = nf_ct_l4proto_net(net,
	541	&nf_conntrack_l4proto_generic);
	542
	543	pn->users--;
15f585bd	544	nf_ct_l4proto_unregister_sysctl(net,
fa34fff5	545	pn,
15f585bd	546	&nf_conntrack_l4proto_generic);
04d87001 G	547	}
	548
	549	int nf_conntrack_proto_init(void)
	550	{
	551	unsigned int i;
	552	for (i = 0; i < AF_MAX; i++)
	553	rcu_assign_pointer(nf_ct_l3protos[i],
	554	&nf_conntrack_l3proto_generic);
	555	return 0;
	556	}
	557
	558	void nf_conntrack_proto_fini(void)
	559	{
	560	unsigned int i;
	561	/* free l3proto protocol tables */
	562	for (i = 0; i < PF_MAX; i++)
	563	kfree(nf_ct_protos[i]);
ac5357eb	564	}