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 int 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_counter *acct;
43 
44 	acct = nf_conn_acct_find(ct);
45 	if (!acct)
46 		return 0;
47 
48 	return seq_printf(s, "packets=%llu bytes=%llu ",
49 			  (unsigned long long)acct[dir].packets,
50 			  (unsigned long long)acct[dir].bytes);
51 };
52 EXPORT_SYMBOL_GPL(seq_print_acct);
53 
54 static struct nf_ct_ext_type acct_extend __read_mostly = {
55 	.len	= sizeof(struct nf_conn_counter[IP_CT_DIR_MAX]),
56 	.align	= __alignof__(struct nf_conn_counter[IP_CT_DIR_MAX]),
57 	.id	= NF_CT_EXT_ACCT,
58 };
59 
60 #ifdef CONFIG_SYSCTL
61 static int nf_conntrack_acct_init_sysctl(struct net *net)
62 {
63 	struct ctl_table *table;
64 
65 	table = kmemdup(acct_sysctl_table, sizeof(acct_sysctl_table),
66 			GFP_KERNEL);
67 	if (!table)
68 		goto out;
69 
70 	table[0].data = &net->ct.sysctl_acct;
71 
72 	net->ct.acct_sysctl_header = register_net_sysctl_table(net,
73 			nf_net_netfilter_sysctl_path, table);
74 	if (!net->ct.acct_sysctl_header) {
75 		printk(KERN_ERR "nf_conntrack_acct: can't register to sysctl.\n");
76 		goto out_register;
77 	}
78 	return 0;
79 
80 out_register:
81 	kfree(table);
82 out:
83 	return -ENOMEM;
84 }
85 
86 static void nf_conntrack_acct_fini_sysctl(struct net *net)
87 {
88 	struct ctl_table *table;
89 
90 	table = net->ct.acct_sysctl_header->ctl_table_arg;
91 	unregister_net_sysctl_table(net->ct.acct_sysctl_header);
92 	kfree(table);
93 }
94 #else
95 static int nf_conntrack_acct_init_sysctl(struct net *net)
96 {
97 	return 0;
98 }
99 
100 static void nf_conntrack_acct_fini_sysctl(struct net *net)
101 {
102 }
103 #endif
104 
105 int nf_conntrack_acct_init(struct net *net)
106 {
107 	int ret;
108 
109 	net->ct.sysctl_acct = nf_ct_acct;
110 
111 	if (net_eq(net, &init_net)) {
112 		ret = nf_ct_extend_register(&acct_extend);
113 		if (ret < 0) {
114 			printk(KERN_ERR "nf_conntrack_acct: Unable to register extension\n");
115 			goto out_extend_register;
116 		}
117 	}
118 
119 	ret = nf_conntrack_acct_init_sysctl(net);
120 	if (ret < 0)
121 		goto out_sysctl;
122 
123 	return 0;
124 
125 out_sysctl:
126 	if (net_eq(net, &init_net))
127 		nf_ct_extend_unregister(&acct_extend);
128 out_extend_register:
129 	return ret;
130 }
131 
132 void nf_conntrack_acct_fini(struct net *net)
133 {
134 	nf_conntrack_acct_fini_sysctl(net);
135 	if (net_eq(net, &init_net))
136 		nf_ct_extend_unregister(&acct_extend);
137 }
138