LXR linux/net/ipv6/netfilter/ip6table

   1/*
   2 * "security" table for IPv6
   3 *
   4 * This is for use by Mandatory Access Control (MAC) security models,
   5 * which need to be able to manage security policy in separate context
   6 * to DAC.
   7 *
   8 * Based on iptable_mangle.c
   9 *
  10 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
  11 * Copyright (C) 2000-2004 Netfilter Core Team <coreteam <at> netfilter.org>
  12 * Copyright (C) 2008 Red Hat, Inc., James Morris <jmorris <at> redhat.com>
  13 *
  14 * This program is free software; you can redistribute it and/or modify
  15 * it under the terms of the GNU General Public License version 2 as
  16 * published by the Free Software Foundation.
  17 */
  18#include <linux/module.h>
  19#include <linux/netfilter_ipv6/ip6_tables.h>
  20#include <linux/slab.h>
  21
  22MODULE_LICENSE("GPL");
  23MODULE_AUTHOR("James Morris <jmorris <at> redhat.com>");
  24MODULE_DESCRIPTION("ip6tables security table, for MAC rules");
  25
  26#define SECURITY_VALID_HOOKS    (1 << NF_INET_LOCAL_IN) | \
  27                                (1 << NF_INET_FORWARD) | \
  28                                (1 << NF_INET_LOCAL_OUT)
  29
  30static const struct xt_table security_table = {
  31        .name           = "security",
  32        .valid_hooks    = SECURITY_VALID_HOOKS,
  33        .me             = THIS_MODULE,
  34        .af             = NFPROTO_IPV6,
  35        .priority       = NF_IP6_PRI_SECURITY,
  36};
  37
  38static unsigned int
  39ip6table_security_hook(unsigned int hook, struct sk_buff *skb,
  40                       const struct net_device *in,
  41                       const struct net_device *out,
  42                       int (*okfn)(struct sk_buff *))
  43{
  44        const struct net *net = dev_net((in != NULL) ? in : out);
  45
  46        return ip6t_do_table(skb, hook, in, out, net->ipv6.ip6table_security);
  47}
  48
  49static struct nf_hook_ops *sectbl_ops __read_mostly;
  50
  51static int __net_init ip6table_security_net_init(struct net *net)
  52{
  53        struct ip6t_replace *repl;
  54
  55        repl = ip6t_alloc_initial_table(&security_table);
  56        if (repl == NULL)
  57                return -ENOMEM;
  58        net->ipv6.ip6table_security =
  59                ip6t_register_table(net, &security_table, repl);
  60        kfree(repl);
  61        if (IS_ERR(net->ipv6.ip6table_security))
  62                return PTR_ERR(net->ipv6.ip6table_security);
  63
  64        return 0;
  65}
  66
  67static void __net_exit ip6table_security_net_exit(struct net *net)
  68{
  69        ip6t_unregister_table(net, net->ipv6.ip6table_security);
  70}
  71
  72static struct pernet_operations ip6table_security_net_ops = {
  73        .init = ip6table_security_net_init,
  74        .exit = ip6table_security_net_exit,
  75};
  76
  77static int __init ip6table_security_init(void)
  78{
  79        int ret;
  80
  81        ret = register_pernet_subsys(&ip6table_security_net_ops);
  82        if (ret < 0)
  83                return ret;
  84
  85        sectbl_ops = xt_hook_link(&security_table, ip6table_security_hook);
  86        if (IS_ERR(sectbl_ops)) {
  87                ret = PTR_ERR(sectbl_ops);
  88                goto cleanup_table;
  89        }
  90
  91        return ret;
  92
  93cleanup_table:
  94        unregister_pernet_subsys(&ip6table_security_net_ops);
  95        return ret;
  96}
  97
  98static void __exit ip6table_security_fini(void)
  99{
 100        xt_hook_unlink(&security_table, sectbl_ops);
 101        unregister_pernet_subsys(&ip6table_security_net_ops);
 102}
 103
 104module_init(ip6table_security_init);
 105module_exit(ip6table_security_fini);
 106