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 
21 static bool nf_ct_acct __read_mostly;
22 
23 module_param_named(acct, nf_ct_acct, bool, 0644);
24 MODULE_PARM_DESC(acct, "Enable connection tracking flow accounting.");
25 
26 #ifdef CONFIG_SYSCTL
27 static 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 
39 unsigned int
40 seq_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 };
56 EXPORT_SYMBOL_GPL(seq_print_acct);
57 
58 static 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
65 static 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 
88 out_register:
89 	kfree(table);
90 out:
91 	return -ENOMEM;
92 }
93 
94 static 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
103 static int nf_conntrack_acct_init_sysctl(struct net *net)
104 {
105 	return 0;
106 }
107 
108 static void nf_conntrack_acct_fini_sysctl(struct net *net)
109 {
110 }
111 #endif
112 
113 int 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 
119 void nf_conntrack_acct_pernet_fini(struct net *net)
120 {
121 	nf_conntrack_acct_fini_sysctl(net);
122 }
123 
124 int 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 
132 void nf_conntrack_acct_fini(void)
133 {
134 	nf_ct_extend_unregister(&acct_extend);
135 }
136