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#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
  23static bool nf_ct_acct __read_mostly;
  24
  25module_param_named(acct, nf_ct_acct, bool, 0644);
  26MODULE_PARM_DESC(acct, "Enable connection tracking flow accounting.");
  27
  28#ifdef CONFIG_SYSCTL
  29static 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
  41unsigned int
  42seq_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};
  58EXPORT_SYMBOL_GPL(seq_print_acct);
  59
  60static 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
  67static 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
  90out_register:
  91        kfree(table);
  92out:
  93        return -ENOMEM;
  94}
  95
  96static 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
 105static int nf_conntrack_acct_init_sysctl(struct net *net)
 106{
 107        return 0;
 108}
 109
 110static void nf_conntrack_acct_fini_sysctl(struct net *net)
 111{
 112}
 113#endif
 114
 115int 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
 121void nf_conntrack_acct_pernet_fini(struct net *net)
 122{
 123        nf_conntrack_acct_fini_sysctl(net);
 124}
 125
 126int 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
 134void nf_conntrack_acct_fini(void)
 135{
 136        nf_ct_extend_unregister(&acct_extend);
 137}
 138