[mirror_ubuntu-artful-kernel.git] / net / netfilter / nfnetlink.c

/* Netfilter messages via netlink socket. Allows for user space
 * protocol helpers and general trouble making from userspace.
 *
 * (C) 2001 by Jay Schulist <jschlst@samba.org>,
 * (C) 2002-2005 by Harald Welte <laforge@gnumonks.org>
 * (C) 2005-2017 by Pablo Neira Ayuso <pablo@netfilter.org>
 *
 * Initial netfilter messages via netlink development funded and
 * generally made possible by Network Robots, Inc. (www.networkrobots.com)
 *
 * Further development of this code funded by Astaro AG (http://www.astaro.com)
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/uaccess.h>
#include <net/sock.h>
#include <linux/init.h>

#include <net/netlink.h>
#include <linux/netfilter/nfnetlink.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NETFILTER);

#define nfnl_dereference_protected(id) \
	rcu_dereference_protected(table[(id)].subsys, \
				  lockdep_nfnl_is_held((id)))

static char __initdata nfversion[] = "0.30";

static struct {
	struct mutex				mutex;
	const struct nfnetlink_subsystem __rcu	*subsys;
} table[NFNL_SUBSYS_COUNT];

static const int nfnl_group2type[NFNLGRP_MAX+1] = {
	[NFNLGRP_CONNTRACK_NEW]		= NFNL_SUBSYS_CTNETLINK,
	[NFNLGRP_CONNTRACK_UPDATE]	= NFNL_SUBSYS_CTNETLINK,
	[NFNLGRP_CONNTRACK_DESTROY]	= NFNL_SUBSYS_CTNETLINK,
	[NFNLGRP_CONNTRACK_EXP_NEW]	= NFNL_SUBSYS_CTNETLINK_EXP,
	[NFNLGRP_CONNTRACK_EXP_UPDATE]	= NFNL_SUBSYS_CTNETLINK_EXP,
	[NFNLGRP_CONNTRACK_EXP_DESTROY] = NFNL_SUBSYS_CTNETLINK_EXP,
	[NFNLGRP_NFTABLES]		= NFNL_SUBSYS_NFTABLES,
	[NFNLGRP_ACCT_QUOTA]		= NFNL_SUBSYS_ACCT,
	[NFNLGRP_NFTRACE]		= NFNL_SUBSYS_NFTABLES,
};

void nfnl_lock(__u8 subsys_id)
{
	mutex_lock(&table[subsys_id].mutex);
}
EXPORT_SYMBOL_GPL(nfnl_lock);

void nfnl_unlock(__u8 subsys_id)
{
	mutex_unlock(&table[subsys_id].mutex);
}
EXPORT_SYMBOL_GPL(nfnl_unlock);

#ifdef CONFIG_PROVE_LOCKING
bool lockdep_nfnl_is_held(u8 subsys_id)
{
	return lockdep_is_held(&table[subsys_id].mutex);
}
EXPORT_SYMBOL_GPL(lockdep_nfnl_is_held);
#endif

int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n)
{
	nfnl_lock(n->subsys_id);
	if (table[n->subsys_id].subsys) {
		nfnl_unlock(n->subsys_id);
		return -EBUSY;
	}
	rcu_assign_pointer(table[n->subsys_id].subsys, n);
	nfnl_unlock(n->subsys_id);

	return 0;
}
EXPORT_SYMBOL_GPL(nfnetlink_subsys_register);

int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n)
{
	nfnl_lock(n->subsys_id);
	table[n->subsys_id].subsys = NULL;
	nfnl_unlock(n->subsys_id);
	synchronize_rcu();
	return 0;
}
EXPORT_SYMBOL_GPL(nfnetlink_subsys_unregister);

static inline const struct nfnetlink_subsystem *nfnetlink_get_subsys(u16 type)
{
	u8 subsys_id = NFNL_SUBSYS_ID(type);

	if (subsys_id >= NFNL_SUBSYS_COUNT)
		return NULL;

	return rcu_dereference(table[subsys_id].subsys);
}

static inline const struct nfnl_callback *
nfnetlink_find_client(u16 type, const struct nfnetlink_subsystem *ss)
{
	u8 cb_id = NFNL_MSG_TYPE(type);

	if (cb_id >= ss->cb_count)
		return NULL;

	return &ss->cb[cb_id];
}

int nfnetlink_has_listeners(struct net *net, unsigned int group)
{
	return netlink_has_listeners(net->nfnl, group);
}
EXPORT_SYMBOL_GPL(nfnetlink_has_listeners);

int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid,
		   unsigned int group, int echo, gfp_t flags)
{
	return nlmsg_notify(net->nfnl, skb, portid, group, echo, flags);
}
EXPORT_SYMBOL_GPL(nfnetlink_send);

int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error)
{
	return netlink_set_err(net->nfnl, portid, group, error);
}
EXPORT_SYMBOL_GPL(nfnetlink_set_err);

int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid,
		      int flags)
{
	return netlink_unicast(net->nfnl, skb, portid, flags);
}
EXPORT_SYMBOL_GPL(nfnetlink_unicast);

/* Process one complete nfnetlink message. */
static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
			     struct netlink_ext_ack *extack)
{
	struct net *net = sock_net(skb->sk);
	const struct nfnl_callback *nc;
	const struct nfnetlink_subsystem *ss;
	int type, err;

	/* All the messages must at least contain nfgenmsg */
	if (nlmsg_len(nlh) < sizeof(struct nfgenmsg))
		return 0;

	type = nlh->nlmsg_type;
replay:
	rcu_read_lock();
	ss = nfnetlink_get_subsys(type);
	if (!ss) {
#ifdef CONFIG_MODULES
		rcu_read_unlock();
		request_module("nfnetlink-subsys-%d", NFNL_SUBSYS_ID(type));
		rcu_read_lock();
		ss = nfnetlink_get_subsys(type);
		if (!ss)
#endif
		{
			rcu_read_unlock();
			return -EINVAL;
		}
	}

	nc = nfnetlink_find_client(type, ss);
	if (!nc) {
		rcu_read_unlock();
		return -EINVAL;
	}

	{
		int min_len = nlmsg_total_size(sizeof(struct nfgenmsg));
		u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type);
		struct nlattr *cda[ss->cb[cb_id].attr_count + 1];
		struct nlattr *attr = (void *)nlh + min_len;
		int attrlen = nlh->nlmsg_len - min_len;
		__u8 subsys_id = NFNL_SUBSYS_ID(type);

		err = nla_parse(cda, ss->cb[cb_id].attr_count, attr, attrlen,
				ss->cb[cb_id].policy, extack);
		if (err < 0) {
			rcu_read_unlock();
			return err;
		}

		if (nc->call_rcu) {
			err = nc->call_rcu(net, net->nfnl, skb, nlh,
					   (const struct nlattr **)cda,
					   extack);
			rcu_read_unlock();
		} else {
			rcu_read_unlock();
			nfnl_lock(subsys_id);
			if (nfnl_dereference_protected(subsys_id) != ss ||
			    nfnetlink_find_client(type, ss) != nc)
				err = -EAGAIN;
			else if (nc->call)
				err = nc->call(net, net->nfnl, skb, nlh,
					       (const struct nlattr **)cda,
					       extack);
			else
				err = -EINVAL;
			nfnl_unlock(subsys_id);
		}
		if (err == -EAGAIN)
			goto replay;
		return err;
	}
}

struct nfnl_err {
	struct list_head	head;
	struct nlmsghdr		*nlh;
	int			err;
	struct netlink_ext_ack	extack;
};

static int nfnl_err_add(struct list_head *list, struct nlmsghdr *nlh, int err,
			const struct netlink_ext_ack *extack)
{
	struct nfnl_err *nfnl_err;

	nfnl_err = kmalloc(sizeof(struct nfnl_err), GFP_KERNEL);
	if (nfnl_err == NULL)
		return -ENOMEM;

	nfnl_err->nlh = nlh;
	nfnl_err->err = err;
	nfnl_err->extack = *extack;
	list_add_tail(&nfnl_err->head, list);

	return 0;
}

static void nfnl_err_del(struct nfnl_err *nfnl_err)
{
	list_del(&nfnl_err->head);
	kfree(nfnl_err);
}

static void nfnl_err_reset(struct list_head *err_list)
{
	struct nfnl_err *nfnl_err, *next;

	list_for_each_entry_safe(nfnl_err, next, err_list, head)
		nfnl_err_del(nfnl_err);
}

static void nfnl_err_deliver(struct list_head *err_list, struct sk_buff *skb)
{
	struct nfnl_err *nfnl_err, *next;

	list_for_each_entry_safe(nfnl_err, next, err_list, head) {
		netlink_ack(skb, nfnl_err->nlh, nfnl_err->err,
			    &nfnl_err->extack);
		nfnl_err_del(nfnl_err);
	}
}

enum {
	NFNL_BATCH_FAILURE	= (1 << 0),
	NFNL_BATCH_DONE		= (1 << 1),
	NFNL_BATCH_REPLAY	= (1 << 2),
};

static void nfnetlink_rcv_batch(struct sk_buff *skb, struct nlmsghdr *nlh,
				u16 subsys_id, u32 genid)
{
	struct sk_buff *oskb = skb;
	struct net *net = sock_net(skb->sk);
	const struct nfnetlink_subsystem *ss;
	const struct nfnl_callback *nc;
	struct netlink_ext_ack extack;
	LIST_HEAD(err_list);
	u32 status;
	int err;

	if (subsys_id >= NFNL_SUBSYS_COUNT)
		return netlink_ack(skb, nlh, -EINVAL, NULL);
replay:
	status = 0;

	skb = netlink_skb_clone(oskb, GFP_KERNEL);
	if (!skb)
		return netlink_ack(oskb, nlh, -ENOMEM, NULL);

	nfnl_lock(subsys_id);
	ss = nfnl_dereference_protected(subsys_id);
	if (!ss) {
#ifdef CONFIG_MODULES
		nfnl_unlock(subsys_id);
		request_module("nfnetlink-subsys-%d", subsys_id);
		nfnl_lock(subsys_id);
		ss = nfnl_dereference_protected(subsys_id);
		if (!ss)
#endif
		{
			nfnl_unlock(subsys_id);
			netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL);
			return kfree_skb(skb);
		}
	}

	if (!ss->commit || !ss->abort) {
		nfnl_unlock(subsys_id);
		netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL);
		return kfree_skb(skb);
	}

	if (genid && ss->valid_genid && !ss->valid_genid(net, genid)) {
		nfnl_unlock(subsys_id);
		netlink_ack(oskb, nlh, -ERESTART, NULL);
		return kfree_skb(skb);
	}

	while (skb->len >= nlmsg_total_size(0)) {
		int msglen, type;

		memset(&extack, 0, sizeof(extack));
		nlh = nlmsg_hdr(skb);
		err = 0;

		if (nlh->nlmsg_len < NLMSG_HDRLEN ||
		    skb->len < nlh->nlmsg_len ||
		    nlmsg_len(nlh) < sizeof(struct nfgenmsg)) {
			nfnl_err_reset(&err_list);
			status |= NFNL_BATCH_FAILURE;
			goto done;
		}

		/* Only requests are handled by the kernel */
		if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) {
			err = -EINVAL;
			goto ack;
		}

		type = nlh->nlmsg_type;
		if (type == NFNL_MSG_BATCH_BEGIN) {
			/* Malformed: Batch begin twice */
			nfnl_err_reset(&err_list);
			status |= NFNL_BATCH_FAILURE;
			goto done;
		} else if (type == NFNL_MSG_BATCH_END) {
			status |= NFNL_BATCH_DONE;
			goto done;
		} else if (type < NLMSG_MIN_TYPE) {
			err = -EINVAL;
			goto ack;
		}

		/* We only accept a batch with messages for the same
		 * subsystem.
		 */
		if (NFNL_SUBSYS_ID(type) != subsys_id) {
			err = -EINVAL;
			goto ack;
		}

		nc = nfnetlink_find_client(type, ss);
		if (!nc) {
			err = -EINVAL;
			goto ack;
		}

		{
			int min_len = nlmsg_total_size(sizeof(struct nfgenmsg));
			u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type);
			struct nlattr *cda[ss->cb[cb_id].attr_count + 1];
			struct nlattr *attr = (void *)nlh + min_len;
			int attrlen = nlh->nlmsg_len - min_len;

			err = nla_parse(cda, ss->cb[cb_id].attr_count, attr,
					attrlen, ss->cb[cb_id].policy, NULL);
			if (err < 0)
				goto ack;

			if (nc->call_batch) {
				err = nc->call_batch(net, net->nfnl, skb, nlh,
						     (const struct nlattr **)cda,
						     &extack);
			}

			/* The lock was released to autoload some module, we
			 * have to abort and start from scratch using the
			 * original skb.
			 */
			if (err == -EAGAIN) {
				status |= NFNL_BATCH_REPLAY;
				goto next;
			}
		}
ack:
		if (nlh->nlmsg_flags & NLM_F_ACK || err) {
			/* Errors are delivered once the full batch has been
			 * processed, this avoids that the same error is
			 * reported several times when replaying the batch.
			 */
			if (nfnl_err_add(&err_list, nlh, err, &extack) < 0) {
				/* We failed to enqueue an error, reset the
				 * list of errors and send OOM to userspace
				 * pointing to the batch header.
				 */
				nfnl_err_reset(&err_list);
				netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM,
					    NULL);
				status |= NFNL_BATCH_FAILURE;
				goto done;
			}
			/* We don't stop processing the batch on errors, thus,
			 * userspace gets all the errors that the batch
			 * triggers.
			 */
			if (err)
				status |= NFNL_BATCH_FAILURE;
		}
next:
		msglen = NLMSG_ALIGN(nlh->nlmsg_len);
		if (msglen > skb->len)
			msglen = skb->len;
		skb_pull(skb, msglen);
	}
done:
	if (status & NFNL_BATCH_REPLAY) {
		ss->abort(net, oskb);
		nfnl_err_reset(&err_list);
		nfnl_unlock(subsys_id);
		kfree_skb(skb);
		goto replay;
	} else if (status == NFNL_BATCH_DONE) {
		ss->commit(net, oskb);
	} else {
		ss->abort(net, oskb);
	}

	nfnl_err_deliver(&err_list, oskb);
	nfnl_unlock(subsys_id);
	kfree_skb(skb);
}

static const struct nla_policy nfnl_batch_policy[NFNL_BATCH_MAX + 1] = {
	[NFNL_BATCH_GENID]	= { .type = NLA_U32 },
};

static void nfnetlink_rcv_skb_batch(struct sk_buff *skb, struct nlmsghdr *nlh)
{
	int min_len = nlmsg_total_size(sizeof(struct nfgenmsg));
	struct nlattr *attr = (void *)nlh + min_len;
	struct nlattr *cda[NFNL_BATCH_MAX + 1];
	int attrlen = nlh->nlmsg_len - min_len;
	struct nfgenmsg *nfgenmsg;
	int msglen, err;
	u32 gen_id = 0;
	u16 res_id;

	msglen = NLMSG_ALIGN(nlh->nlmsg_len);
	if (msglen > skb->len)
		msglen = skb->len;

	if (skb->len < NLMSG_HDRLEN + sizeof(struct nfgenmsg))
		return;

	err = nla_parse(cda, NFNL_BATCH_MAX, attr, attrlen, nfnl_batch_policy,
			NULL);
	if (err < 0) {
		netlink_ack(skb, nlh, err, NULL);
		return;
	}
	if (cda[NFNL_BATCH_GENID])
		gen_id = ntohl(nla_get_be32(cda[NFNL_BATCH_GENID]));

	nfgenmsg = nlmsg_data(nlh);
	skb_pull(skb, msglen);
	/* Work around old nft using host byte order */
	if (nfgenmsg->res_id == NFNL_SUBSYS_NFTABLES)
		res_id = NFNL_SUBSYS_NFTABLES;
	else
		res_id = ntohs(nfgenmsg->res_id);

	nfnetlink_rcv_batch(skb, nlh, res_id, gen_id);
}

static void nfnetlink_rcv(struct sk_buff *skb)
{
	struct nlmsghdr *nlh = nlmsg_hdr(skb);

	if (skb->len < NLMSG_HDRLEN ||
	    nlh->nlmsg_len < NLMSG_HDRLEN ||
	    skb->len < nlh->nlmsg_len)
		return;

	if (!netlink_net_capable(skb, CAP_NET_ADMIN)) {
		netlink_ack(skb, nlh, -EPERM, NULL);
		return;
	}

	if (nlh->nlmsg_type == NFNL_MSG_BATCH_BEGIN)
		nfnetlink_rcv_skb_batch(skb, nlh);
	else
		netlink_rcv_skb(skb, nfnetlink_rcv_msg);
}

#ifdef CONFIG_MODULES
static int nfnetlink_bind(struct net *net, int group)
{
	const struct nfnetlink_subsystem *ss;
	int type;

	if (group <= NFNLGRP_NONE || group > NFNLGRP_MAX)
		return 0;

	type = nfnl_group2type[group];

	rcu_read_lock();
	ss = nfnetlink_get_subsys(type << 8);
	rcu_read_unlock();
	if (!ss)
		request_module("nfnetlink-subsys-%d", type);
	return 0;
}
#endif

static int __net_init nfnetlink_net_init(struct net *net)
{
	struct sock *nfnl;
	struct netlink_kernel_cfg cfg = {
		.groups	= NFNLGRP_MAX,
		.input	= nfnetlink_rcv,
#ifdef CONFIG_MODULES
		.bind	= nfnetlink_bind,
#endif
	};

	nfnl = netlink_kernel_create(net, NETLINK_NETFILTER, &cfg);
	if (!nfnl)
		return -ENOMEM;
	net->nfnl_stash = nfnl;
	rcu_assign_pointer(net->nfnl, nfnl);
	return 0;
}

static void __net_exit nfnetlink_net_exit_batch(struct list_head *net_exit_list)
{
	struct net *net;

	list_for_each_entry(net, net_exit_list, exit_list)
		RCU_INIT_POINTER(net->nfnl, NULL);
	synchronize_net();
	list_for_each_entry(net, net_exit_list, exit_list)
		netlink_kernel_release(net->nfnl_stash);
}

static struct pernet_operations nfnetlink_net_ops = {
	.init		= nfnetlink_net_init,
	.exit_batch	= nfnetlink_net_exit_batch,
};

static int __init nfnetlink_init(void)
{
	int i;

	for (i = NFNLGRP_NONE + 1; i <= NFNLGRP_MAX; i++)
		BUG_ON(nfnl_group2type[i] == NFNL_SUBSYS_NONE);

	for (i=0; i<NFNL_SUBSYS_COUNT; i++)
		mutex_init(&table[i].mutex);

	pr_info("Netfilter messages via NETLINK v%s.\n", nfversion);
	return register_pernet_subsys(&nfnetlink_net_ops);
}

static void __exit nfnetlink_exit(void)
{
	pr_info("Removing netfilter NETLINK layer.\n");
	unregister_pernet_subsys(&nfnetlink_net_ops);
}
module_init(nfnetlink_init);
module_exit(nfnetlink_exit);
Commit	Line	Data
f9e815b3 HW	1	/* Netfilter messages via netlink socket. Allows for user space
	2	* protocol helpers and general trouble making from userspace.
	3	*
	4	* (C) 2001 by Jay Schulist <jschlst@samba.org>,
	5	* (C) 2002-2005 by Harald Welte <laforge@gnumonks.org>
8c4d4e8b	6	* (C) 2005-2017 by Pablo Neira Ayuso <pablo@netfilter.org>
f9e815b3 HW	7	*
	8	* Initial netfilter messages via netlink development funded and
	9	* generally made possible by Network Robots, Inc. (www.networkrobots.com)
	10	*
	11	* Further development of this code funded by Astaro AG (http://www.astaro.com)
	12	*
	13	* This software may be used and distributed according to the terms
	14	* of the GNU General Public License, incorporated herein by reference.
	15	*/
	16
f9e815b3 HW	17	#include <linux/module.h>
	18	#include <linux/types.h>
	19	#include <linux/socket.h>
	20	#include <linux/kernel.h>
f9e815b3 HW	21	#include <linux/string.h>
	22	#include <linux/sockios.h>
	23	#include <linux/net.h>
f9e815b3	24	#include <linux/skbuff.h>
7c0f6ba6	25	#include <linux/uaccess.h>
f9e815b3 HW	26	#include <net/sock.h>
f9e815b3 HW	27	#include <linux/init.h>
f9e815b3	28
573ce260	29	#include <net/netlink.h>
f9e815b3 HW	30	#include <linux/netfilter/nfnetlink.h>
	31
	32	MODULE_LICENSE("GPL");
4fdb3bb7 HW	33	MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
4fdb3bb7 HW	34	MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NETFILTER);
f9e815b3	35
9c55d3b5 FW	36	#define nfnl_dereference_protected(id) \
	37	rcu_dereference_protected(table[(id)].subsys, \
	38	lockdep_nfnl_is_held((id)))
	39
f9e815b3 HW	40	static char __initdata nfversion[] = "0.30";
f9e815b3 HW	41
c14b78e7 PNA	42	static struct {
	43	struct mutex mutex;
	44	const struct nfnetlink_subsystem __rcu *subsys;
	45	} table[NFNL_SUBSYS_COUNT];
f9e815b3	46
03292745 PNA	47	static const int nfnl_group2type[NFNLGRP_MAX+1] = {
	48	[NFNLGRP_CONNTRACK_NEW] = NFNL_SUBSYS_CTNETLINK,
	49	[NFNLGRP_CONNTRACK_UPDATE] = NFNL_SUBSYS_CTNETLINK,
	50	[NFNLGRP_CONNTRACK_DESTROY] = NFNL_SUBSYS_CTNETLINK,
	51	[NFNLGRP_CONNTRACK_EXP_NEW] = NFNL_SUBSYS_CTNETLINK_EXP,
	52	[NFNLGRP_CONNTRACK_EXP_UPDATE] = NFNL_SUBSYS_CTNETLINK_EXP,
	53	[NFNLGRP_CONNTRACK_EXP_DESTROY] = NFNL_SUBSYS_CTNETLINK_EXP,
97840cb6 PNA	54	[NFNLGRP_NFTABLES] = NFNL_SUBSYS_NFTABLES,
97840cb6 PNA	55	[NFNLGRP_ACCT_QUOTA] = NFNL_SUBSYS_ACCT,
33d5a7b1	56	[NFNLGRP_NFTRACE] = NFNL_SUBSYS_NFTABLES,
03292745 PNA	57	};
03292745 PNA	58
c14b78e7	59	void nfnl_lock(__u8 subsys_id)
f9e815b3	60	{
c14b78e7	61	mutex_lock(&table[subsys_id].mutex);
f9e815b3	62	}
e6a7d3c0	63	EXPORT_SYMBOL_GPL(nfnl_lock);
f9e815b3	64
c14b78e7	65	void nfnl_unlock(__u8 subsys_id)
a3c5029c	66	{
c14b78e7	67	mutex_unlock(&table[subsys_id].mutex);
f9e815b3	68	}
e6a7d3c0	69	EXPORT_SYMBOL_GPL(nfnl_unlock);
f9e815b3	70
0eb5db7a	71	#ifdef CONFIG_PROVE_LOCKING
875e0829	72	bool lockdep_nfnl_is_held(u8 subsys_id)
0eb5db7a PM	73	{
	74	return lockdep_is_held(&table[subsys_id].mutex);
	75	}
	76	EXPORT_SYMBOL_GPL(lockdep_nfnl_is_held);
	77	#endif
	78
7c8d4cb4	79	int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n)
f9e815b3	80	{
c14b78e7 PNA	81	nfnl_lock(n->subsys_id);
	82	if (table[n->subsys_id].subsys) {
	83	nfnl_unlock(n->subsys_id);
0ab43f84 HW	84	return -EBUSY;
0ab43f84 HW	85	}
c14b78e7 PNA	86	rcu_assign_pointer(table[n->subsys_id].subsys, n);
c14b78e7 PNA	87	nfnl_unlock(n->subsys_id);
f9e815b3 HW	88
	89	return 0;
	90	}
f4bc177f	91	EXPORT_SYMBOL_GPL(nfnetlink_subsys_register);
f9e815b3	92
7c8d4cb4	93	int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n)
f9e815b3	94	{
c14b78e7 PNA	95	nfnl_lock(n->subsys_id);
	96	table[n->subsys_id].subsys = NULL;
	97	nfnl_unlock(n->subsys_id);
6b75e3e8	98	synchronize_rcu();
f9e815b3 HW	99	return 0;
f9e815b3 HW	100	}
f4bc177f	101	EXPORT_SYMBOL_GPL(nfnetlink_subsys_unregister);
f9e815b3	102
b745d035	103	static inline const struct nfnetlink_subsystem *nfnetlink_get_subsys(u16 type)
f9e815b3	104	{
b745d035	105	u8 subsys_id = NFNL_SUBSYS_ID(type);
f9e815b3	106
ac0f1d98	107	if (subsys_id >= NFNL_SUBSYS_COUNT)
f9e815b3 HW	108	return NULL;
f9e815b3 HW	109
c14b78e7	110	return rcu_dereference(table[subsys_id].subsys);
f9e815b3 HW	111	}
f9e815b3 HW	112
7c8d4cb4	113	static inline const struct nfnl_callback *
b745d035	114	nfnetlink_find_client(u16 type, const struct nfnetlink_subsystem *ss)
f9e815b3	115	{
b745d035	116	u8 cb_id = NFNL_MSG_TYPE(type);
601e68e1	117
67ca3966	118	if (cb_id >= ss->cb_count)
f9e815b3	119	return NULL;
f9e815b3 HW	120
	121	return &ss->cb[cb_id];
	122	}
	123
cd8c20b6	124	int nfnetlink_has_listeners(struct net *net, unsigned int group)
a2427692	125	{
cd8c20b6	126	return netlink_has_listeners(net->nfnl, group);
a2427692 PM	127	}
	128	EXPORT_SYMBOL_GPL(nfnetlink_has_listeners);
	129
ec464e5d	130	int nfnetlink_send(struct sk_buff skb, struct net net, u32 portid,
95c96174	131	unsigned int group, int echo, gfp_t flags)
f9e815b3	132	{
ec464e5d	133	return nlmsg_notify(net->nfnl, skb, portid, group, echo, flags);
f9e815b3	134	}
f4bc177f	135	EXPORT_SYMBOL_GPL(nfnetlink_send);
f9e815b3	136
ec464e5d	137	int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error)
dd5b6ce6	138	{
ec464e5d	139	return netlink_set_err(net->nfnl, portid, group, error);
dd5b6ce6 PNA	140	}
	141	EXPORT_SYMBOL_GPL(nfnetlink_set_err);
	142
ec464e5d PM	143	int nfnetlink_unicast(struct sk_buff skb, struct net net, u32 portid,
ec464e5d PM	144	int flags)
f9e815b3	145	{
ec464e5d	146	return netlink_unicast(net->nfnl, skb, portid, flags);
f9e815b3	147	}
f4bc177f	148	EXPORT_SYMBOL_GPL(nfnetlink_unicast);
f9e815b3 HW	149
f9e815b3 HW	150	/* Process one complete nfnetlink message. */
2d4bc933 JB	151	static int nfnetlink_rcv_msg(struct sk_buff skb, struct nlmsghdr nlh,
2d4bc933 JB	152	struct netlink_ext_ack *extack)
f9e815b3	153	{
cd8c20b6	154	struct net *net = sock_net(skb->sk);
7c8d4cb4 PM	155	const struct nfnl_callback *nc;
7c8d4cb4 PM	156	const struct nfnetlink_subsystem *ss;
1d00a4eb	157	int type, err;
f9e815b3	158
f9e815b3	159	/* All the messages must at least contain nfgenmsg */
573ce260	160	if (nlmsg_len(nlh) < sizeof(struct nfgenmsg))
f9e815b3	161	return 0;
f9e815b3 HW	162
f9e815b3 HW	163	type = nlh->nlmsg_type;
e6a7d3c0	164	replay:
6b75e3e8	165	rcu_read_lock();
f9e815b3	166	ss = nfnetlink_get_subsys(type);
0ab43f84	167	if (!ss) {
95a5afca	168	#ifdef CONFIG_MODULES
6b75e3e8	169	rcu_read_unlock();
37d2e7a2	170	request_module("nfnetlink-subsys-%d", NFNL_SUBSYS_ID(type));
6b75e3e8	171	rcu_read_lock();
37d2e7a2	172	ss = nfnetlink_get_subsys(type);
0ab43f84 HW	173	if (!ss)
0ab43f84 HW	174	#endif
6b75e3e8 ED	175	{
6b75e3e8 ED	176	rcu_read_unlock();
1d00a4eb	177	return -EINVAL;
6b75e3e8	178	}
0ab43f84	179	}
f9e815b3 HW	180
f9e815b3 HW	181	nc = nfnetlink_find_client(type, ss);
6b75e3e8 ED	182	if (!nc) {
6b75e3e8 ED	183	rcu_read_unlock();
1d00a4eb	184	return -EINVAL;
6b75e3e8	185	}
f9e815b3	186
f9e815b3	187	{
573ce260	188	int min_len = nlmsg_total_size(sizeof(struct nfgenmsg));
b745d035	189	u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type);
f49c857f PNA	190	struct nlattr *cda[ss->cb[cb_id].attr_count + 1];
	191	struct nlattr attr = (void )nlh + min_len;
	192	int attrlen = nlh->nlmsg_len - min_len;
c14b78e7	193	__u8 subsys_id = NFNL_SUBSYS_ID(type);
f49c857f	194
fceb6435	195	err = nla_parse(cda, ss->cb[cb_id].attr_count, attr, attrlen,
fe52145f	196	ss->cb[cb_id].policy, extack);
4009e188 TB	197	if (err < 0) {
4009e188 TB	198	rcu_read_unlock();
f49c857f	199	return err;
4009e188	200	}
601e68e1	201
6b75e3e8	202	if (nc->call_rcu) {
7b8002a1	203	err = nc->call_rcu(net, net->nfnl, skb, nlh,
04ba724b PNA	204	(const struct nlattr **)cda,
04ba724b PNA	205	extack);
6b75e3e8 ED	206	rcu_read_unlock();
	207	} else {
	208	rcu_read_unlock();
c14b78e7	209	nfnl_lock(subsys_id);
9c55d3b5	210	if (nfnl_dereference_protected(subsys_id) != ss \|\|
6b75e3e8 ED	211	nfnetlink_find_client(type, ss) != nc)
6b75e3e8 ED	212	err = -EAGAIN;
59560a38	213	else if (nc->call)
7b8002a1	214	err = nc->call(net, net->nfnl, skb, nlh,
04ba724b PNA	215	(const struct nlattr **)cda,
04ba724b PNA	216	extack);
59560a38 TB	217	else
59560a38 TB	218	err = -EINVAL;
c14b78e7	219	nfnl_unlock(subsys_id);
6b75e3e8	220	}
e6a7d3c0 PNA	221	if (err == -EAGAIN)
	222	goto replay;
	223	return err;
f9e815b3	224	}
f9e815b3 HW	225	}
f9e815b3 HW	226
cbb8125e PNA	227	struct nfnl_err {
	228	struct list_head head;
	229	struct nlmsghdr *nlh;
	230	int err;
04ba724b	231	struct netlink_ext_ack extack;
cbb8125e PNA	232	};
cbb8125e PNA	233
04ba724b PNA	234	static int nfnl_err_add(struct list_head list, struct nlmsghdr nlh, int err,
04ba724b PNA	235	const struct netlink_ext_ack *extack)
cbb8125e PNA	236	{
	237	struct nfnl_err *nfnl_err;
	238
	239	nfnl_err = kmalloc(sizeof(struct nfnl_err), GFP_KERNEL);
	240	if (nfnl_err == NULL)
	241	return -ENOMEM;
	242
	243	nfnl_err->nlh = nlh;
	244	nfnl_err->err = err;
04ba724b	245	nfnl_err->extack = *extack;
cbb8125e PNA	246	list_add_tail(&nfnl_err->head, list);
	247
	248	return 0;
	249	}
	250
	251	static void nfnl_err_del(struct nfnl_err *nfnl_err)
	252	{
	253	list_del(&nfnl_err->head);
	254	kfree(nfnl_err);
	255	}
	256
	257	static void nfnl_err_reset(struct list_head *err_list)
	258	{
	259	struct nfnl_err nfnl_err, next;
	260
	261	list_for_each_entry_safe(nfnl_err, next, err_list, head)
	262	nfnl_err_del(nfnl_err);
	263	}
	264
	265	static void nfnl_err_deliver(struct list_head err_list, struct sk_buff skb)
	266	{
	267	struct nfnl_err nfnl_err, next;
	268
	269	list_for_each_entry_safe(nfnl_err, next, err_list, head) {
04ba724b PNA	270	netlink_ack(skb, nfnl_err->nlh, nfnl_err->err,
04ba724b PNA	271	&nfnl_err->extack);
cbb8125e PNA	272	nfnl_err_del(nfnl_err);
	273	}
	274	}
	275
6742b9e3 PNA	276	enum {
	277	NFNL_BATCH_FAILURE = (1 << 0),
	278	NFNL_BATCH_DONE = (1 << 1),
	279	NFNL_BATCH_REPLAY = (1 << 2),
	280	};
	281
0628b123	282	static void nfnetlink_rcv_batch(struct sk_buff skb, struct nlmsghdr nlh,
8c4d4e8b	283	u16 subsys_id, u32 genid)
0628b123	284	{
0f816232	285	struct sk_buff *oskb = skb;
0628b123 PNA	286	struct net *net = sock_net(skb->sk);
	287	const struct nfnetlink_subsystem *ss;
	288	const struct nfnl_callback *nc;
04ba724b	289	struct netlink_ext_ack extack;
4eba8b78	290	LIST_HEAD(err_list);
6742b9e3	291	u32 status;
0628b123 PNA	292	int err;
	293
	294	if (subsys_id >= NFNL_SUBSYS_COUNT)
2d4bc933	295	return netlink_ack(skb, nlh, -EINVAL, NULL);
0628b123	296	replay:
6742b9e3 PNA	297	status = 0;
6742b9e3 PNA	298
0f816232 DJ	299	skb = netlink_skb_clone(oskb, GFP_KERNEL);
0f816232 DJ	300	if (!skb)
2d4bc933	301	return netlink_ack(oskb, nlh, -ENOMEM, NULL);
0628b123	302
0628b123	303	nfnl_lock(subsys_id);
9c55d3b5	304	ss = nfnl_dereference_protected(subsys_id);
0628b123 PNA	305	if (!ss) {
	306	#ifdef CONFIG_MODULES
	307	nfnl_unlock(subsys_id);
	308	request_module("nfnetlink-subsys-%d", subsys_id);
	309	nfnl_lock(subsys_id);
9c55d3b5	310	ss = nfnl_dereference_protected(subsys_id);
0628b123 PNA	311	if (!ss)
	312	#endif
	313	{
	314	nfnl_unlock(subsys_id);
2d4bc933	315	netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL);
0f816232	316	return kfree_skb(skb);
0628b123 PNA	317	}
	318	}
	319
	320	if (!ss->commit \|\| !ss->abort) {
	321	nfnl_unlock(subsys_id);
2d4bc933	322	netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL);
ecd15dd7	323	return kfree_skb(skb);
0628b123 PNA	324	}
0628b123 PNA	325
8c4d4e8b PNA	326	if (genid && ss->valid_genid && !ss->valid_genid(net, genid)) {
8c4d4e8b PNA	327	nfnl_unlock(subsys_id);
2d4bc933	328	netlink_ack(oskb, nlh, -ERESTART, NULL);
8c4d4e8b PNA	329	return kfree_skb(skb);
	330	}
	331
0628b123 PNA	332	while (skb->len >= nlmsg_total_size(0)) {
	333	int msglen, type;
	334
04ba724b	335	memset(&extack, 0, sizeof(extack));
0628b123 PNA	336	nlh = nlmsg_hdr(skb);
	337	err = 0;
	338
c58d6c93 PT	339	if (nlh->nlmsg_len < NLMSG_HDRLEN \|\|
	340	skb->len < nlh->nlmsg_len \|\|
	341	nlmsg_len(nlh) < sizeof(struct nfgenmsg)) {
	342	nfnl_err_reset(&err_list);
	343	status \|= NFNL_BATCH_FAILURE;
	344	goto done;
0628b123 PNA	345	}
	346
	347	/* Only requests are handled by the kernel */
	348	if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) {
	349	err = -EINVAL;
	350	goto ack;
	351	}
	352
	353	type = nlh->nlmsg_type;
	354	if (type == NFNL_MSG_BATCH_BEGIN) {
	355	/* Malformed: Batch begin twice */
cbb8125e	356	nfnl_err_reset(&err_list);
6742b9e3	357	status \|= NFNL_BATCH_FAILURE;
0628b123 PNA	358	goto done;
0628b123 PNA	359	} else if (type == NFNL_MSG_BATCH_END) {
6742b9e3	360	status \|= NFNL_BATCH_DONE;
0628b123 PNA	361	goto done;
	362	} else if (type < NLMSG_MIN_TYPE) {
	363	err = -EINVAL;
	364	goto ack;
	365	}
	366
	367	/* We only accept a batch with messages for the same
	368	* subsystem.
	369	*/
	370	if (NFNL_SUBSYS_ID(type) != subsys_id) {
	371	err = -EINVAL;
	372	goto ack;
	373	}
	374
	375	nc = nfnetlink_find_client(type, ss);
	376	if (!nc) {
	377	err = -EINVAL;
	378	goto ack;
	379	}
	380
	381	{
	382	int min_len = nlmsg_total_size(sizeof(struct nfgenmsg));
b745d035	383	u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type);
0628b123 PNA	384	struct nlattr *cda[ss->cb[cb_id].attr_count + 1];
	385	struct nlattr attr = (void )nlh + min_len;
	386	int attrlen = nlh->nlmsg_len - min_len;
	387
fceb6435 JB	388	err = nla_parse(cda, ss->cb[cb_id].attr_count, attr,
fceb6435 JB	389	attrlen, ss->cb[cb_id].policy, NULL);
0628b123 PNA	390	if (err < 0)
	391	goto ack;
	392
	393	if (nc->call_batch) {
633c9a84	394	err = nc->call_batch(net, net->nfnl, skb, nlh,
04ba724b PNA	395	(const struct nlattr **)cda,
04ba724b PNA	396	&extack);
0628b123 PNA	397	}
	398
	399	/* The lock was released to autoload some module, we
	400	* have to abort and start from scratch using the
	401	* original skb.
	402	*/
	403	if (err == -EAGAIN) {
6742b9e3 PNA	404	status \|= NFNL_BATCH_REPLAY;
6742b9e3 PNA	405	goto next;
0628b123 PNA	406	}
	407	}
	408	ack:
	409	if (nlh->nlmsg_flags & NLM_F_ACK \|\| err) {
cbb8125e PNA	410	/* Errors are delivered once the full batch has been
	411	* processed, this avoids that the same error is
	412	* reported several times when replaying the batch.
	413	*/
04ba724b	414	if (nfnl_err_add(&err_list, nlh, err, &extack) < 0) {
cbb8125e PNA	415	/* We failed to enqueue an error, reset the
	416	* list of errors and send OOM to userspace
	417	* pointing to the batch header.
	418	*/
	419	nfnl_err_reset(&err_list);
2d4bc933 JB	420	netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM,
2d4bc933 JB	421	NULL);
6742b9e3	422	status \|= NFNL_BATCH_FAILURE;
cbb8125e PNA	423	goto done;
cbb8125e PNA	424	}
0628b123 PNA	425	/* We don't stop processing the batch on errors, thus,
	426	* userspace gets all the errors that the batch
	427	* triggers.
	428	*/
0628b123	429	if (err)
6742b9e3	430	status \|= NFNL_BATCH_FAILURE;
0628b123	431	}
6742b9e3	432	next:
0628b123 PNA	433	msglen = NLMSG_ALIGN(nlh->nlmsg_len);
	434	if (msglen > skb->len)
	435	msglen = skb->len;
	436	skb_pull(skb, msglen);
	437	}
	438	done:
6742b9e3	439	if (status & NFNL_BATCH_REPLAY) {
5913beaf	440	ss->abort(net, oskb);
6742b9e3 PNA	441	nfnl_err_reset(&err_list);
	442	nfnl_unlock(subsys_id);
	443	kfree_skb(skb);
	444	goto replay;
	445	} else if (status == NFNL_BATCH_DONE) {
5913beaf	446	ss->commit(net, oskb);
6742b9e3	447	} else {
5913beaf	448	ss->abort(net, oskb);
6742b9e3	449	}
0628b123	450
cbb8125e	451	nfnl_err_deliver(&err_list, oskb);
0628b123	452	nfnl_unlock(subsys_id);
0f816232	453	kfree_skb(skb);
0628b123 PNA	454	}
0628b123 PNA	455
8c4d4e8b PNA	456	static const struct nla_policy nfnl_batch_policy[NFNL_BATCH_MAX + 1] = {
	457	[NFNL_BATCH_GENID] = { .type = NLA_U32 },
	458	};
	459
48656835	460	static void nfnetlink_rcv_skb_batch(struct sk_buff skb, struct nlmsghdr nlh)
f9e815b3	461	{
8c4d4e8b PNA	462	int min_len = nlmsg_total_size(sizeof(struct nfgenmsg));
	463	struct nlattr attr = (void )nlh + min_len;
	464	struct nlattr *cda[NFNL_BATCH_MAX + 1];
	465	int attrlen = nlh->nlmsg_len - min_len;
48656835	466	struct nfgenmsg *nfgenmsg;
8c4d4e8b PNA	467	int msglen, err;
8c4d4e8b PNA	468	u32 gen_id = 0;
b745d035	469	u16 res_id;
0628b123	470
48656835 PNA	471	msglen = NLMSG_ALIGN(nlh->nlmsg_len);
	472	if (msglen > skb->len)
	473	msglen = skb->len;
	474
f55ce7b0	475	if (skb->len < NLMSG_HDRLEN + sizeof(struct nfgenmsg))
48656835 PNA	476	return;
48656835 PNA	477
fceb6435 JB	478	err = nla_parse(cda, NFNL_BATCH_MAX, attr, attrlen, nfnl_batch_policy,
fceb6435 JB	479	NULL);
8c4d4e8b	480	if (err < 0) {
2d4bc933	481	netlink_ack(skb, nlh, err, NULL);
8c4d4e8b PNA	482	return;
	483	}
	484	if (cda[NFNL_BATCH_GENID])
	485	gen_id = ntohl(nla_get_be32(cda[NFNL_BATCH_GENID]));
	486
48656835 PNA	487	nfgenmsg = nlmsg_data(nlh);
	488	skb_pull(skb, msglen);
	489	/* Work around old nft using host byte order */
	490	if (nfgenmsg->res_id == NFNL_SUBSYS_NFTABLES)
	491	res_id = NFNL_SUBSYS_NFTABLES;
	492	else
	493	res_id = ntohs(nfgenmsg->res_id);
	494
8c4d4e8b	495	nfnetlink_rcv_batch(skb, nlh, res_id, gen_id);
48656835 PNA	496	}
	497
	498	static void nfnetlink_rcv(struct sk_buff *skb)
	499	{
	500	struct nlmsghdr *nlh = nlmsg_hdr(skb);
	501
f55ce7b0 MJ	502	if (skb->len < NLMSG_HDRLEN \|\|
f55ce7b0 MJ	503	nlh->nlmsg_len < NLMSG_HDRLEN \|\|
0628b123 PNA	504	skb->len < nlh->nlmsg_len)
	505	return;
	506
90f62cf3	507	if (!netlink_net_capable(skb, CAP_NET_ADMIN)) {
2d4bc933	508	netlink_ack(skb, nlh, -EPERM, NULL);
cdbe7c2d JB	509	return;
	510	}
	511
48656835 PNA	512	if (nlh->nlmsg_type == NFNL_MSG_BATCH_BEGIN)
	513	nfnetlink_rcv_skb_batch(skb, nlh);
	514	else
d4ef3835	515	netlink_rcv_skb(skb, nfnetlink_rcv_msg);
f9e815b3 HW	516	}
f9e815b3 HW	517
03292745	518	#ifdef CONFIG_MODULES
023e2cfa	519	static int nfnetlink_bind(struct net *net, int group)
03292745 PNA	520	{
03292745 PNA	521	const struct nfnetlink_subsystem *ss;
97840cb6 PNA	522	int type;
	523
	524	if (group <= NFNLGRP_NONE \|\| group > NFNLGRP_MAX)
62924af2	525	return 0;
97840cb6 PNA	526
97840cb6 PNA	527	type = nfnl_group2type[group];
03292745 PNA	528
03292745 PNA	529	rcu_read_lock();
dbc3617f	530	ss = nfnetlink_get_subsys(type << 8);
03292745	531	rcu_read_unlock();
bfe4bc71 RGB	532	if (!ss)
bfe4bc71 RGB	533	request_module("nfnetlink-subsys-%d", type);
4f520900	534	return 0;
03292745 PNA	535	}
	536	#endif
	537
cd8c20b6	538	static int __net_init nfnetlink_net_init(struct net *net)
f9e815b3	539	{
cd8c20b6	540	struct sock *nfnl;
a31f2d17 PNA	541	struct netlink_kernel_cfg cfg = {
	542	.groups = NFNLGRP_MAX,
	543	.input = nfnetlink_rcv,
03292745 PNA	544	#ifdef CONFIG_MODULES
	545	.bind = nfnetlink_bind,
	546	#endif
a31f2d17	547	};
cd8c20b6	548
9f00d977	549	nfnl = netlink_kernel_create(net, NETLINK_NETFILTER, &cfg);
cd8c20b6 AD	550	if (!nfnl)
	551	return -ENOMEM;
	552	net->nfnl_stash = nfnl;
cf778b00	553	rcu_assign_pointer(net->nfnl, nfnl);
cd8c20b6	554	return 0;
f9e815b3 HW	555	}
f9e815b3 HW	556
cd8c20b6	557	static void __net_exit nfnetlink_net_exit_batch(struct list_head *net_exit_list)
f9e815b3	558	{
cd8c20b6	559	struct net *net;
f9e815b3	560
cd8c20b6	561	list_for_each_entry(net, net_exit_list, exit_list)
a9b3cd7f	562	RCU_INIT_POINTER(net->nfnl, NULL);
cd8c20b6 AD	563	synchronize_net();
	564	list_for_each_entry(net, net_exit_list, exit_list)
	565	netlink_kernel_release(net->nfnl_stash);
	566	}
f9e815b3	567
cd8c20b6 AD	568	static struct pernet_operations nfnetlink_net_ops = {
	569	.init = nfnetlink_net_init,
	570	.exit_batch = nfnetlink_net_exit_batch,
	571	};
	572
	573	static int __init nfnetlink_init(void)
	574	{
c14b78e7 PNA	575	int i;
c14b78e7 PNA	576
97840cb6 PNA	577	for (i = NFNLGRP_NONE + 1; i <= NFNLGRP_MAX; i++)
	578	BUG_ON(nfnl_group2type[i] == NFNL_SUBSYS_NONE);
	579
c14b78e7 PNA	580	for (i=0; i<NFNL_SUBSYS_COUNT; i++)
	581	mutex_init(&table[i].mutex);
	582
654d0fbd	583	pr_info("Netfilter messages via NETLINK v%s.\n", nfversion);
cd8c20b6	584	return register_pernet_subsys(&nfnetlink_net_ops);
f9e815b3 HW	585	}
f9e815b3 HW	586
cd8c20b6 AD	587	static void __exit nfnetlink_exit(void)
cd8c20b6 AD	588	{
654d0fbd	589	pr_info("Removing netfilter NETLINK layer.\n");
cd8c20b6 AD	590	unregister_pernet_subsys(&nfnetlink_net_ops);
cd8c20b6 AD	591	}
f9e815b3 HW	592	module_init(nfnetlink_init);
f9e815b3 HW	593	module_exit(nfnetlink_exit);