LXR linux/net/netfilter/nf_conntrack

   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
  21static bool nf_ct_acct __read_mostly;
  22
  23module_param_named(acct, nf_ct_acct, bool, 0644);
  24MODULE_PARM_DESC(acct, "Enable connection tracking flow accounting.");
  25
  26#ifdef CONFIG_SYSCTL
  27static 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
  39unsigned int
  40seq_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};
  52EXPORT_SYMBOL_GPL(seq_print_acct);
  53
  54static 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
  61static 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
  80out_register:
  81        kfree(table);
  82out:
  83        return -ENOMEM;
  84}
  85
  86static 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
  95static int nf_conntrack_acct_init_sysctl(struct net *net)
  96{
  97        return 0;
  98}
  99
 100static void nf_conntrack_acct_fini_sysctl(struct net *net)
 101{
 102}
 103#endif
 104
 105int 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
 125out_sysctl:
 126        if (net_eq(net, &init_net))
 127                nf_ct_extend_unregister(&acct_extend);
 128out_extend_register:
 129        return ret;
 130}
 131
 132void 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