net/netfilter/nf_conntrack_acct.c

   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_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)atomic64_read(&acct[dir].packets),
  50                           (unsigned long long)atomic64_read(&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         /* Don't export sysctls to unprivileged users */
  73         if (net->user_ns != &init_user_ns)
  74                 table[0].procname = NULL;
  75
  76         net->ct.acct_sysctl_header = register_net_sysctl(net, "net/netfilter",
  77                                                          table);
  78         if (!net->ct.acct_sysctl_header) {
  79                 printk(KERN_ERR "nf_conntrack_acct: can't register to sysctl.\n");
  80                 goto out_register;
  81         }
  82         return 0;
  83
  84 out_register:
  85         kfree(table);
  86 out:
  87         return -ENOMEM;
  88 }
  89
  90 static void nf_conntrack_acct_fini_sysctl(struct net *net)
  91 {
  92         struct ctl_table *table;
  93
  94         table = net->ct.acct_sysctl_header->ctl_table_arg;
  95         unregister_net_sysctl_table(net->ct.acct_sysctl_header);
  96         kfree(table);
  97 }
  98 #else
  99 static int nf_conntrack_acct_init_sysctl(struct net *net)
 100 {
 101         return 0;
 102 }
 103
 104 static void nf_conntrack_acct_fini_sysctl(struct net *net)
 105 {
 106 }
 107 #endif
 108
 109 int nf_conntrack_acct_pernet_init(struct net *net)
 110 {
 111         net->ct.sysctl_acct = nf_ct_acct;
 112         return nf_conntrack_acct_init_sysctl(net);
 113 }
 114
 115 void nf_conntrack_acct_pernet_fini(struct net *net)
 116 {
 117         nf_conntrack_acct_fini_sysctl(net);
 118 }
 119
 120 int nf_conntrack_acct_init(void)
 121 {
 122         int ret = nf_ct_extend_register(&acct_extend);
 123         if (ret < 0)
 124                 pr_err("nf_conntrack_acct: Unable to register extension\n");
 125         return ret;
 126 }
 127
 128 void nf_conntrack_acct_fini(void)
 129 {
 130         nf_ct_extend_unregister(&acct_extend);
 131 }