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         net->ct.acct_sysctl_header = register_net_sysctl(net, "net/netfilter",
  73                                                          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 }