1/* Accouting handling for netfilter. */
2
3/*
4 * (C) 2008 Krzysztof Piotr Oledzki <ole@ans.pl>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/netfilter.h>
12#include <linux/slab.h>
13#include <linux/kernel.h>
14#include <linux/moduleparam.h>
15#include <linux/export.h>
16
17#include <net/netfilter/nf_conntrack.h>
18#include <net/netfilter/nf_conntrack_extend.h>
19#include <net/netfilter/nf_conntrack_acct.h>
20
21static bool nf_ct_acct __read_mostly;
22
23module_param_named(acct, nf_ct_acct, bool, 0644);
24MODULE_PARM_DESC(acct, "Enable connection tracking flow accounting.");
25
26#ifdef CONFIG_SYSCTL
27static struct ctl_table acct_sysctl_table[] = {
28	{
29		.procname	= "nf_conntrack_acct",
30		.data		= &init_net.ct.sysctl_acct,
31		.maxlen		= sizeof(unsigned int),
32		.mode		= 0644,
33		.proc_handler	= proc_dointvec,
34	},
35	{}
36};
37#endif /* CONFIG_SYSCTL */
38
39unsigned int
40seq_print_acct(struct seq_file *s, const struct nf_conn *ct, int dir)
41{
42	struct nf_conn_acct *acct;
43	struct nf_conn_counter *counter;
44
45	acct = nf_conn_acct_find(ct);
46	if (!acct)
47		return 0;
48
49	counter = acct->counter;
50	seq_printf(s, "packets=%llu bytes=%llu ",
51		   (unsigned long long)atomic64_read(&counter[dir].packets),
52		   (unsigned long long)atomic64_read(&counter[dir].bytes));
53
54	return 0;
55};
56EXPORT_SYMBOL_GPL(seq_print_acct);
57
58static struct nf_ct_ext_type acct_extend __read_mostly = {
59	.len	= sizeof(struct nf_conn_acct),
60	.align	= __alignof__(struct nf_conn_acct),
61	.id	= NF_CT_EXT_ACCT,
62};
63
64#ifdef CONFIG_SYSCTL
65static int nf_conntrack_acct_init_sysctl(struct net *net)
66{
67	struct ctl_table *table;
68
69	table = kmemdup(acct_sysctl_table, sizeof(acct_sysctl_table),
70			GFP_KERNEL);
71	if (!table)
72		goto out;
73
74	table[0].data = &net->ct.sysctl_acct;
75
76	/* Don't export sysctls to unprivileged users */
77	if (net->user_ns != &init_user_ns)
78		table[0].procname = NULL;
79
80	net->ct.acct_sysctl_header = register_net_sysctl(net, "net/netfilter",
81							 table);
82	if (!net->ct.acct_sysctl_header) {
83		printk(KERN_ERR "nf_conntrack_acct: can't register to sysctl.\n");
84		goto out_register;
85	}
86	return 0;
87
88out_register:
89	kfree(table);
90out:
91	return -ENOMEM;
92}
93
94static void nf_conntrack_acct_fini_sysctl(struct net *net)
95{
96	struct ctl_table *table;
97
98	table = net->ct.acct_sysctl_header->ctl_table_arg;
99	unregister_net_sysctl_table(net->ct.acct_sysctl_header);
100	kfree(table);
101}
102#else
103static int nf_conntrack_acct_init_sysctl(struct net *net)
104{
105	return 0;
106}
107
108static void nf_conntrack_acct_fini_sysctl(struct net *net)
109{
110}
111#endif
112
113int nf_conntrack_acct_pernet_init(struct net *net)
114{
115	net->ct.sysctl_acct = nf_ct_acct;
116	return nf_conntrack_acct_init_sysctl(net);
117}
118
119void nf_conntrack_acct_pernet_fini(struct net *net)
120{
121	nf_conntrack_acct_fini_sysctl(net);
122}
123
124int nf_conntrack_acct_init(void)
125{
126	int ret = nf_ct_extend_register(&acct_extend);
127	if (ret < 0)
128		pr_err("nf_conntrack_acct: Unable to register extension\n");
129	return ret;
130}
131
132void nf_conntrack_acct_fini(void)
133{
134	nf_ct_extend_unregister(&acct_extend);
135}
136