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_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 const struct nf_ct_ext_type acct_extend = {
  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 }