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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12
  13 #include <linux/netfilter.h>
  14 #include <linux/slab.h>
  15 #include <linux/kernel.h>
  16 #include <linux/moduleparam.h>
  17 #include <linux/export.h>
  18
  19 #include <net/netfilter/nf_conntrack.h>
  20 #include <net/netfilter/nf_conntrack_extend.h>
  21 #include <net/netfilter/nf_conntrack_acct.h>
  22
  23 static bool nf_ct_acct __read_mostly;
  24
  25 module_param_named(acct, nf_ct_acct, bool, 0644);
  26 MODULE_PARM_DESC(acct, "Enable connection tracking flow accounting.");
  27
  28 #ifdef CONFIG_SYSCTL
  29 static struct ctl_table acct_sysctl_table[] = {
  30         {
  31                 .procname       = "nf_conntrack_acct",
  32                 .data           = &init_net.ct.sysctl_acct,
  33                 .maxlen         = sizeof(unsigned int),
  34                 .mode           = 0644,
  35                 .proc_handler   = proc_dointvec,
  36         },
  37         {}
  38 };
  39 #endif /* CONFIG_SYSCTL */
  40
  41 unsigned int
  42 seq_print_acct(struct seq_file *s, const struct nf_conn *ct, int dir)
  43 {
  44         struct nf_conn_acct *acct;
  45         struct nf_conn_counter *counter;
  46
  47         acct = nf_conn_acct_find(ct);
  48         if (!acct)
  49                 return 0;
  50
  51         counter = acct->counter;
  52         seq_printf(s, "packets=%llu bytes=%llu ",
  53                    (unsigned long long)atomic64_read(&counter[dir].packets),
  54                    (unsigned long long)atomic64_read(&counter[dir].bytes));
  55
  56         return 0;
  57 };
  58 EXPORT_SYMBOL_GPL(seq_print_acct);
  59
  60 static const struct nf_ct_ext_type acct_extend = {
  61         .len    = sizeof(struct nf_conn_acct),
  62         .align  = __alignof__(struct nf_conn_acct),
  63         .id     = NF_CT_EXT_ACCT,
  64 };
  65
  66 #ifdef CONFIG_SYSCTL
  67 static int nf_conntrack_acct_init_sysctl(struct net *net)
  68 {
  69         struct ctl_table *table;
  70
  71         table = kmemdup(acct_sysctl_table, sizeof(acct_sysctl_table),
  72                         GFP_KERNEL);
  73         if (!table)
  74                 goto out;
  75
  76         table[0].data = &net->ct.sysctl_acct;
  77
  78         /* Don't export sysctls to unprivileged users */
  79         if (net->user_ns != &init_user_ns)
  80                 table[0].procname = NULL;
  81
  82         net->ct.acct_sysctl_header = register_net_sysctl(net, "net/netfilter",
  83                                                          table);
  84         if (!net->ct.acct_sysctl_header) {
  85                 pr_err("can't register to sysctl\n");
  86                 goto out_register;
  87         }
  88         return 0;
  89
  90 out_register:
  91         kfree(table);
  92 out:
  93         return -ENOMEM;
  94 }
  95
  96 static void nf_conntrack_acct_fini_sysctl(struct net *net)
  97 {
  98         struct ctl_table *table;
  99
 100         table = net->ct.acct_sysctl_header->ctl_table_arg;
 101         unregister_net_sysctl_table(net->ct.acct_sysctl_header);
 102         kfree(table);
 103 }
 104 #else
 105 static int nf_conntrack_acct_init_sysctl(struct net *net)
 106 {
 107         return 0;
 108 }
 109
 110 static void nf_conntrack_acct_fini_sysctl(struct net *net)
 111 {
 112 }
 113 #endif
 114
 115 int nf_conntrack_acct_pernet_init(struct net *net)
 116 {
 117         net->ct.sysctl_acct = nf_ct_acct;
 118         return nf_conntrack_acct_init_sysctl(net);
 119 }
 120
 121 void nf_conntrack_acct_pernet_fini(struct net *net)
 122 {
 123         nf_conntrack_acct_fini_sysctl(net);
 124 }
 125
 126 int nf_conntrack_acct_init(void)
 127 {
 128         int ret = nf_ct_extend_register(&acct_extend);
 129         if (ret < 0)
 130                 pr_err("Unable to register extension\n");
 131         return ret;
 132 }
 133
 134 void nf_conntrack_acct_fini(void)
 135 {
 136         nf_ct_extend_unregister(&acct_extend);
 137 }