[deliverable/linux.git] / net / netfilter / nfnetlink_acct.c

/*
 * (C) 2011 Pablo Neira Ayuso <pablo@netfilter.org>
 * (C) 2011 Intra2net AG <http://www.intra2net.com>
 *
 * 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 (or any later at your option).
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/rculist.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <net/netlink.h>
#include <net/sock.h>
#include <asm/atomic.h>

#include <linux/netfilter.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nfnetlink_acct.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
MODULE_DESCRIPTION("nfacct: Extended Netfilter accounting infrastructure");

static LIST_HEAD(nfnl_acct_list);

struct nf_acct {
	atomic64_t		pkts;
	atomic64_t		bytes;
	struct list_head	head;
	atomic_t		refcnt;
	char			name[NFACCT_NAME_MAX];
	struct rcu_head		rcu_head;
};

static int
nfnl_acct_new(struct sock *nfnl, struct sk_buff *skb,
	     const struct nlmsghdr *nlh, const struct nlattr * const tb[])
{
	struct nf_acct *nfacct, *matching = NULL;
	char *acct_name;

	if (!tb[NFACCT_NAME])
		return -EINVAL;

	acct_name = nla_data(tb[NFACCT_NAME]);

	list_for_each_entry(nfacct, &nfnl_acct_list, head) {
		if (strncmp(nfacct->name, acct_name, NFACCT_NAME_MAX) != 0)
			continue;

                if (nlh->nlmsg_flags & NLM_F_EXCL)
			return -EEXIST;

		matching = nfacct;
		break;
        }

	if (matching) {
		if (nlh->nlmsg_flags & NLM_F_REPLACE) {
			/* reset counters if you request a replacement. */
			atomic64_set(&matching->pkts, 0);
			atomic64_set(&matching->bytes, 0);
			return 0;
		}
		return -EBUSY;
	}

	nfacct = kzalloc(sizeof(struct nf_acct), GFP_KERNEL);
	if (nfacct == NULL)
		return -ENOMEM;

	strncpy(nfacct->name, nla_data(tb[NFACCT_NAME]), NFACCT_NAME_MAX);

	if (tb[NFACCT_BYTES]) {
		atomic64_set(&nfacct->bytes,
			     be64_to_cpu(nla_get_u64(tb[NFACCT_BYTES])));
	}
	if (tb[NFACCT_PKTS]) {
		atomic64_set(&nfacct->pkts,
			     be64_to_cpu(nla_get_u64(tb[NFACCT_PKTS])));
	}
	atomic_set(&nfacct->refcnt, 1);
	list_add_tail_rcu(&nfacct->head, &nfnl_acct_list);
	return 0;
}

static int
nfnl_acct_fill_info(struct sk_buff *skb, u32 pid, u32 seq, u32 type,
		   int event, struct nf_acct *acct)
{
	struct nlmsghdr *nlh;
	struct nfgenmsg *nfmsg;
	unsigned int flags = pid ? NLM_F_MULTI : 0;
	u64 pkts, bytes;

	event |= NFNL_SUBSYS_ACCT << 8;
	nlh = nlmsg_put(skb, pid, seq, event, sizeof(*nfmsg), flags);
	if (nlh == NULL)
		goto nlmsg_failure;

	nfmsg = nlmsg_data(nlh);
	nfmsg->nfgen_family = AF_UNSPEC;
	nfmsg->version = NFNETLINK_V0;
	nfmsg->res_id = 0;

	NLA_PUT_STRING(skb, NFACCT_NAME, acct->name);

	if (type == NFNL_MSG_ACCT_GET_CTRZERO) {
		pkts = atomic64_xchg(&acct->pkts, 0);
		bytes = atomic64_xchg(&acct->bytes, 0);
	} else {
		pkts = atomic64_read(&acct->pkts);
		bytes = atomic64_read(&acct->bytes);
	}
	NLA_PUT_BE64(skb, NFACCT_PKTS, cpu_to_be64(pkts));
	NLA_PUT_BE64(skb, NFACCT_BYTES, cpu_to_be64(bytes));
	NLA_PUT_BE32(skb, NFACCT_USE, htonl(atomic_read(&acct->refcnt)));

	nlmsg_end(skb, nlh);
	return skb->len;

nlmsg_failure:
nla_put_failure:
	nlmsg_cancel(skb, nlh);
	return -1;
}

static int
nfnl_acct_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
	struct nf_acct *cur, *last;

	if (cb->args[2])
		return 0;

	last = (struct nf_acct *)cb->args[1];
	if (cb->args[1])
		cb->args[1] = 0;

	rcu_read_lock();
	list_for_each_entry_rcu(cur, &nfnl_acct_list, head) {
		if (last && cur != last)
			continue;

		if (nfnl_acct_fill_info(skb, NETLINK_CB(cb->skb).pid,
				       cb->nlh->nlmsg_seq,
				       NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
				       NFNL_MSG_ACCT_NEW, cur) < 0) {
			cb->args[1] = (unsigned long)cur;
			break;
		}
	}
	if (!cb->args[1])
		cb->args[2] = 1;
	rcu_read_unlock();
	return skb->len;
}

static int
nfnl_acct_get(struct sock *nfnl, struct sk_buff *skb,
	     const struct nlmsghdr *nlh, const struct nlattr * const tb[])
{
	int ret = -ENOENT;
	struct nf_acct *cur;
	char *acct_name;

	if (nlh->nlmsg_flags & NLM_F_DUMP) {
		return netlink_dump_start(nfnl, skb, nlh, nfnl_acct_dump,
					  NULL, 0);
	}

	if (!tb[NFACCT_NAME])
		return -EINVAL;
	acct_name = nla_data(tb[NFACCT_NAME]);

	list_for_each_entry(cur, &nfnl_acct_list, head) {
		struct sk_buff *skb2;

		if (strncmp(cur->name, acct_name, NFACCT_NAME_MAX)!= 0)
			continue;

		skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
		if (skb2 == NULL) {
			ret = -ENOMEM;
			break;
		}

		ret = nfnl_acct_fill_info(skb2, NETLINK_CB(skb).pid,
					 nlh->nlmsg_seq,
					 NFNL_MSG_TYPE(nlh->nlmsg_type),
					 NFNL_MSG_ACCT_NEW, cur);
		if (ret <= 0) {
			kfree_skb(skb2);
			break;
		}
		ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).pid,
					MSG_DONTWAIT);
		if (ret > 0)
			ret = 0;

		/* this avoids a loop in nfnetlink. */
		return ret == -EAGAIN ? -ENOBUFS : ret;
	}
	return ret;
}

/* try to delete object, fail if it is still in use. */
static int nfnl_acct_try_del(struct nf_acct *cur)
{
	int ret = 0;

	/* we want to avoid races with nfnl_acct_find_get. */
	if (atomic_dec_and_test(&cur->refcnt)) {
		/* We are protected by nfnl mutex. */
		list_del_rcu(&cur->head);
		kfree_rcu(cur, rcu_head);
	} else {
		/* still in use, restore reference counter. */
		atomic_inc(&cur->refcnt);
		ret = -EBUSY;
	}
	return ret;
}

static int
nfnl_acct_del(struct sock *nfnl, struct sk_buff *skb,
	     const struct nlmsghdr *nlh, const struct nlattr * const tb[])
{
	char *acct_name;
	struct nf_acct *cur;
	int ret = -ENOENT;

	if (!tb[NFACCT_NAME]) {
		list_for_each_entry(cur, &nfnl_acct_list, head)
			nfnl_acct_try_del(cur);

		return 0;
	}
	acct_name = nla_data(tb[NFACCT_NAME]);

	list_for_each_entry(cur, &nfnl_acct_list, head) {
		if (strncmp(cur->name, acct_name, NFACCT_NAME_MAX) != 0)
			continue;

		ret = nfnl_acct_try_del(cur);
		if (ret < 0)
			return ret;

		break;
	}
	return ret;
}

static const struct nla_policy nfnl_acct_policy[NFACCT_MAX+1] = {
	[NFACCT_NAME] = { .type = NLA_NUL_STRING, .len = NFACCT_NAME_MAX-1 },
	[NFACCT_BYTES] = { .type = NLA_U64 },
	[NFACCT_PKTS] = { .type = NLA_U64 },
};

static const struct nfnl_callback nfnl_acct_cb[NFNL_MSG_ACCT_MAX] = {
	[NFNL_MSG_ACCT_NEW]		= { .call = nfnl_acct_new,
					    .attr_count = NFACCT_MAX,
					    .policy = nfnl_acct_policy },
	[NFNL_MSG_ACCT_GET] 		= { .call = nfnl_acct_get,
					    .attr_count = NFACCT_MAX,
					    .policy = nfnl_acct_policy },
	[NFNL_MSG_ACCT_GET_CTRZERO] 	= { .call = nfnl_acct_get,
					    .attr_count = NFACCT_MAX,
					    .policy = nfnl_acct_policy },
	[NFNL_MSG_ACCT_DEL]		= { .call = nfnl_acct_del,
					    .attr_count = NFACCT_MAX,
					    .policy = nfnl_acct_policy },
};

static const struct nfnetlink_subsystem nfnl_acct_subsys = {
	.name				= "acct",
	.subsys_id			= NFNL_SUBSYS_ACCT,
	.cb_count			= NFNL_MSG_ACCT_MAX,
	.cb				= nfnl_acct_cb,
};

MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_ACCT);

struct nf_acct *nfnl_acct_find_get(const char *acct_name)
{
	struct nf_acct *cur, *acct = NULL;

	rcu_read_lock();
	list_for_each_entry_rcu(cur, &nfnl_acct_list, head) {
		if (strncmp(cur->name, acct_name, NFACCT_NAME_MAX)!= 0)
			continue;

		if (!try_module_get(THIS_MODULE))
			goto err;

		if (!atomic_inc_not_zero(&cur->refcnt)) {
			module_put(THIS_MODULE);
			goto err;
		}

		acct = cur;
		break;
	}
err:
	rcu_read_unlock();
	return acct;
}
EXPORT_SYMBOL_GPL(nfnl_acct_find_get);

void nfnl_acct_put(struct nf_acct *acct)
{
	atomic_dec(&acct->refcnt);
	module_put(THIS_MODULE);
}
EXPORT_SYMBOL_GPL(nfnl_acct_put);

void nfnl_acct_update(const struct sk_buff *skb, struct nf_acct *nfacct)
{
	atomic64_inc(&nfacct->pkts);
	atomic64_add(skb->len, &nfacct->bytes);
}
EXPORT_SYMBOL_GPL(nfnl_acct_update);

static int __init nfnl_acct_init(void)
{
	int ret;

	pr_info("nfnl_acct: registering with nfnetlink.\n");
	ret = nfnetlink_subsys_register(&nfnl_acct_subsys);
	if (ret < 0) {
		pr_err("nfnl_acct_init: cannot register with nfnetlink.\n");
		goto err_out;
	}
	return 0;
err_out:
	return ret;
}

static void __exit nfnl_acct_exit(void)
{
	struct nf_acct *cur, *tmp;

	pr_info("nfnl_acct: unregistering from nfnetlink.\n");
	nfnetlink_subsys_unregister(&nfnl_acct_subsys);

	list_for_each_entry_safe(cur, tmp, &nfnl_acct_list, head) {
		list_del_rcu(&cur->head);
		/* We are sure that our objects have no clients at this point,
		 * it's safe to release them all without checking refcnt. */
		kfree_rcu(cur, rcu_head);
	}
}

module_init(nfnl_acct_init);
module_exit(nfnl_acct_exit);
Commit	Line	Data
94139027 PNA	1	/*
	2	* (C) 2011 Pablo Neira Ayuso <pablo@netfilter.org>
	3	* (C) 2011 Intra2net AG <http://www.intra2net.com>
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License version 2 as
	7	* published by the Free Software Foundation (or any later at your option).
	8	*/
	9	#include <linux/init.h>
	10	#include <linux/module.h>
	11	#include <linux/kernel.h>
	12	#include <linux/skbuff.h>
	13	#include <linux/netlink.h>
	14	#include <linux/rculist.h>
	15	#include <linux/slab.h>
	16	#include <linux/types.h>
	17	#include <linux/errno.h>
	18	#include <net/netlink.h>
	19	#include <net/sock.h>
	20	#include <asm/atomic.h>
	21
	22	#include <linux/netfilter.h>
	23	#include <linux/netfilter/nfnetlink.h>
	24	#include <linux/netfilter/nfnetlink_acct.h>
	25
	26	MODULE_LICENSE("GPL");
	27	MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
	28	MODULE_DESCRIPTION("nfacct: Extended Netfilter accounting infrastructure");
	29
	30	static LIST_HEAD(nfnl_acct_list);
	31
	32	struct nf_acct {
	33	atomic64_t pkts;
	34	atomic64_t bytes;
	35	struct list_head head;
	36	atomic_t refcnt;
	37	char name[NFACCT_NAME_MAX];
	38	struct rcu_head rcu_head;
	39	};
	40
	41	static int
	42	nfnl_acct_new(struct sock nfnl, struct sk_buff skb,
	43	const struct nlmsghdr nlh, const struct nlattr const tb[])
	44	{
	45	struct nf_acct nfacct, matching = NULL;
	46	char *acct_name;
	47
	48	if (!tb[NFACCT_NAME])
	49	return -EINVAL;
	50
	51	acct_name = nla_data(tb[NFACCT_NAME]);
	52
	53	list_for_each_entry(nfacct, &nfnl_acct_list, head) {
	54	if (strncmp(nfacct->name, acct_name, NFACCT_NAME_MAX) != 0)
	55	continue;
	56
	57	if (nlh->nlmsg_flags & NLM_F_EXCL)
	58	return -EEXIST;
	59
	60	matching = nfacct;
	61	break;
	62	}
	63
	64	if (matching) {
65	if (nlh->nlmsg_flags & NLM_F_REPLACE) {
66	/* reset counters if you request a replacement. */
67	atomic64_set(&matching->pkts, 0);
68	atomic64_set(&matching->bytes, 0);
69	return 0;
70	}
71	return -EBUSY;
72	}
73
74	nfacct = kzalloc(sizeof(struct nf_acct), GFP_KERNEL);
75	if (nfacct == NULL)
76	return -ENOMEM;
77
78	strncpy(nfacct->name, nla_data(tb[NFACCT_NAME]), NFACCT_NAME_MAX);
79
80	if (tb[NFACCT_BYTES]) {
81	atomic64_set(&nfacct->bytes,
82	be64_to_cpu(nla_get_u64(tb[NFACCT_BYTES])));
83	}
84	if (tb[NFACCT_PKTS]) {
85	atomic64_set(&nfacct->pkts,
86	be64_to_cpu(nla_get_u64(tb[NFACCT_PKTS])));
87	}
88	atomic_set(&nfacct->refcnt, 1);
89	list_add_tail_rcu(&nfacct->head, &nfnl_acct_list);
90	return 0;
91	}
92
93	static int
94	nfnl_acct_fill_info(struct sk_buff *skb, u32 pid, u32 seq, u32 type,
95	int event, struct nf_acct *acct)
96	{
97	struct nlmsghdr *nlh;
98	struct nfgenmsg *nfmsg;
99	unsigned int flags = pid ? NLM_F_MULTI : 0;
100	u64 pkts, bytes;
101
102	event \|= NFNL_SUBSYS_ACCT << 8;
103	nlh = nlmsg_put(skb, pid, seq, event, sizeof(*nfmsg), flags);
104	if (nlh == NULL)
105	goto nlmsg_failure;
106
107	nfmsg = nlmsg_data(nlh);
108	nfmsg->nfgen_family = AF_UNSPEC;
109	nfmsg->version = NFNETLINK_V0;
110	nfmsg->res_id = 0;
111
112	NLA_PUT_STRING(skb, NFACCT_NAME, acct->name);
113
114	if (type == NFNL_MSG_ACCT_GET_CTRZERO) {
115	pkts = atomic64_xchg(&acct->pkts, 0);
116	bytes = atomic64_xchg(&acct->bytes, 0);
117	} else {
118	pkts = atomic64_read(&acct->pkts);
119	bytes = atomic64_read(&acct->bytes);
120	}
121	NLA_PUT_BE64(skb, NFACCT_PKTS, cpu_to_be64(pkts));
122	NLA_PUT_BE64(skb, NFACCT_BYTES, cpu_to_be64(bytes));
123	NLA_PUT_BE32(skb, NFACCT_USE, htonl(atomic_read(&acct->refcnt)));
124
125	nlmsg_end(skb, nlh);
126	return skb->len;
127
128	nlmsg_failure:
129	nla_put_failure:
130	nlmsg_cancel(skb, nlh);
131	return -1;
132	}
133
134	static int
135	nfnl_acct_dump(struct sk_buff skb, struct netlink_callback cb)
136	{
137	struct nf_acct cur, last;
138
139	if (cb->args[2])
140	return 0;
141
142	last = (struct nf_acct *)cb->args[1];
143	if (cb->args[1])
144	cb->args[1] = 0;
145
146	rcu_read_lock();
147	list_for_each_entry_rcu(cur, &nfnl_acct_list, head) {
148	if (last && cur != last)
149	continue;
150
151	if (nfnl_acct_fill_info(skb, NETLINK_CB(cb->skb).pid,
152	cb->nlh->nlmsg_seq,
153	NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
154	NFNL_MSG_ACCT_NEW, cur) < 0) {
155	cb->args[1] = (unsigned long)cur;
156	break;
157	}
158	}
159	if (!cb->args[1])
160	cb->args[2] = 1;
161	rcu_read_unlock();
162	return skb->len;
163	}
164
165	static int
166	nfnl_acct_get(struct sock nfnl, struct sk_buff skb,
167	const struct nlmsghdr nlh, const struct nlattr const tb[])
168	{
3ab0b245	169	int ret = -ENOENT;
94139027 PNA	170	struct nf_acct *cur;
	171	char *acct_name;
	172
	173	if (nlh->nlmsg_flags & NLM_F_DUMP) {
	174	return netlink_dump_start(nfnl, skb, nlh, nfnl_acct_dump,
	175	NULL, 0);
	176	}
	177
	178	if (!tb[NFACCT_NAME])
	179	return -EINVAL;
	180	acct_name = nla_data(tb[NFACCT_NAME]);
	181
	182	list_for_each_entry(cur, &nfnl_acct_list, head) {
	183	struct sk_buff *skb2;
	184
	185	if (strncmp(cur->name, acct_name, NFACCT_NAME_MAX)!= 0)
	186	continue;
	187
	188	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
3ab0b245 PNA	189	if (skb2 == NULL) {
3ab0b245 PNA	190	ret = -ENOMEM;
94139027	191	break;
3ab0b245	192	}
94139027 PNA	193
	194	ret = nfnl_acct_fill_info(skb2, NETLINK_CB(skb).pid,
	195	nlh->nlmsg_seq,
	196	NFNL_MSG_TYPE(nlh->nlmsg_type),
	197	NFNL_MSG_ACCT_NEW, cur);
3ab0b245	198	if (ret <= 0) {
94139027	199	kfree_skb(skb2);
3ab0b245 PNA	200	break;
	201	}
	202	ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).pid,
	203	MSG_DONTWAIT);
	204	if (ret > 0)
	205	ret = 0;
94139027	206
3ab0b245 PNA	207	/* this avoids a loop in nfnetlink. */
3ab0b245 PNA	208	return ret == -EAGAIN ? -ENOBUFS : ret;
94139027 PNA	209	}
	210	return ret;
	211	}
	212
	213	/* try to delete object, fail if it is still in use. */
	214	static int nfnl_acct_try_del(struct nf_acct *cur)
	215	{
	216	int ret = 0;
	217
	218	/* we want to avoid races with nfnl_acct_find_get. */
	219	if (atomic_dec_and_test(&cur->refcnt)) {
	220	/* We are protected by nfnl mutex. */
	221	list_del_rcu(&cur->head);
	222	kfree_rcu(cur, rcu_head);
	223	} else {
	224	/* still in use, restore reference counter. */
	225	atomic_inc(&cur->refcnt);
	226	ret = -EBUSY;
	227	}
	228	return ret;
	229	}
	230
	231	static int
	232	nfnl_acct_del(struct sock nfnl, struct sk_buff skb,
	233	const struct nlmsghdr nlh, const struct nlattr const tb[])
	234	{
	235	char *acct_name;
	236	struct nf_acct *cur;
	237	int ret = -ENOENT;
	238
	239	if (!tb[NFACCT_NAME]) {
	240	list_for_each_entry(cur, &nfnl_acct_list, head)
	241	nfnl_acct_try_del(cur);
	242
	243	return 0;
	244	}
	245	acct_name = nla_data(tb[NFACCT_NAME]);
	246
	247	list_for_each_entry(cur, &nfnl_acct_list, head) {
	248	if (strncmp(cur->name, acct_name, NFACCT_NAME_MAX) != 0)
	249	continue;
	250
	251	ret = nfnl_acct_try_del(cur);
	252	if (ret < 0)
	253	return ret;
	254
	255	break;
	256	}
	257	return ret;
	258	}
	259
	260	static const struct nla_policy nfnl_acct_policy[NFACCT_MAX+1] = {
	261	[NFACCT_NAME] = { .type = NLA_NUL_STRING, .len = NFACCT_NAME_MAX-1 },
	262	[NFACCT_BYTES] = { .type = NLA_U64 },
	263	[NFACCT_PKTS] = { .type = NLA_U64 },
	264	};
	265
	266	static const struct nfnl_callback nfnl_acct_cb[NFNL_MSG_ACCT_MAX] = {
	267	[NFNL_MSG_ACCT_NEW] = { .call = nfnl_acct_new,
	268	.attr_count = NFACCT_MAX,
	269	.policy = nfnl_acct_policy },
	270	[NFNL_MSG_ACCT_GET] = { .call = nfnl_acct_get,
	271	.attr_count = NFACCT_MAX,
	272	.policy = nfnl_acct_policy },
273	[NFNL_MSG_ACCT_GET_CTRZERO] = { .call = nfnl_acct_get,
274	.attr_count = NFACCT_MAX,
275	.policy = nfnl_acct_policy },
276	[NFNL_MSG_ACCT_DEL] = { .call = nfnl_acct_del,
277	.attr_count = NFACCT_MAX,
278	.policy = nfnl_acct_policy },
279	};
280
281	static const struct nfnetlink_subsystem nfnl_acct_subsys = {
282	.name = "acct",
283	.subsys_id = NFNL_SUBSYS_ACCT,
284	.cb_count = NFNL_MSG_ACCT_MAX,
285	.cb = nfnl_acct_cb,
286	};
287
288	MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_ACCT);
289
290	struct nf_acct nfnl_acct_find_get(const char acct_name)
291	{
292	struct nf_acct cur, acct = NULL;
293
294	rcu_read_lock();
295	list_for_each_entry_rcu(cur, &nfnl_acct_list, head) {
296	if (strncmp(cur->name, acct_name, NFACCT_NAME_MAX)!= 0)
297	continue;
298
299	if (!try_module_get(THIS_MODULE))
300	goto err;
301
302	if (!atomic_inc_not_zero(&cur->refcnt)) {
303	module_put(THIS_MODULE);
304	goto err;
305	}
306
307	acct = cur;
308	break;
309	}
310	err:
311	rcu_read_unlock();
312	return acct;
313	}
314	EXPORT_SYMBOL_GPL(nfnl_acct_find_get);
315
316	void nfnl_acct_put(struct nf_acct *acct)
317	{
318	atomic_dec(&acct->refcnt);
319	module_put(THIS_MODULE);
320	}
321	EXPORT_SYMBOL_GPL(nfnl_acct_put);
322
323	void nfnl_acct_update(const struct sk_buff skb, struct nf_acct nfacct)
324	{
325	atomic64_inc(&nfacct->pkts);
326	atomic64_add(skb->len, &nfacct->bytes);
327	}
328	EXPORT_SYMBOL_GPL(nfnl_acct_update);
329
330	static int __init nfnl_acct_init(void)
331	{
332	int ret;
333
334	pr_info("nfnl_acct: registering with nfnetlink.\n");
335	ret = nfnetlink_subsys_register(&nfnl_acct_subsys);
336	if (ret < 0) {
337	pr_err("nfnl_acct_init: cannot register with nfnetlink.\n");
338	goto err_out;
339	}
340	return 0;
341	err_out:
342	return ret;
343	}
344
345	static void __exit nfnl_acct_exit(void)
346	{
347	struct nf_acct cur, tmp;
348
349	pr_info("nfnl_acct: unregistering from nfnetlink.\n");
350	nfnetlink_subsys_unregister(&nfnl_acct_subsys);
351
352	list_for_each_entry_safe(cur, tmp, &nfnl_acct_list, head) {
353	list_del_rcu(&cur->head);
354	/* We are sure that our objects have no clients at this point,
355	* it's safe to release them all without checking refcnt. */
356	kfree_rcu(cur, rcu_head);
357	}
358	}
359
360	module_init(nfnl_acct_init);
361	module_exit(nfnl_acct_exit);