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(const struct nf_hook_ops *ops, 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, ops->hooknum, in, out,
  47                             net->ipv6.ip6table_security);
  48}
  49
  50static struct nf_hook_ops *sectbl_ops __read_mostly;
  51
  52static int __net_init ip6table_security_net_init(struct net *net)
  53{
  54        struct ip6t_replace *repl;
  55
  56        repl = ip6t_alloc_initial_table(&security_table);
  57        if (repl == NULL)
  58                return -ENOMEM;
  59        net->ipv6.ip6table_security =
  60                ip6t_register_table(net, &security_table, repl);
  61        kfree(repl);
  62        return PTR_ERR_OR_ZERO(net->ipv6.ip6table_security);
  63}
  64
  65static void __net_exit ip6table_security_net_exit(struct net *net)
  66{
  67        ip6t_unregister_table(net, net->ipv6.ip6table_security);
  68}
  69
  70static struct pernet_operations ip6table_security_net_ops = {
  71        .init = ip6table_security_net_init,
  72        .exit = ip6table_security_net_exit,
  73};
  74
  75static int __init ip6table_security_init(void)
  76{
  77        int ret;
  78
  79        ret = register_pernet_subsys(&ip6table_security_net_ops);
  80        if (ret < 0)
  81                return ret;
  82
  83        sectbl_ops = xt_hook_link(&security_table, ip6table_security_hook);
  84        if (IS_ERR(sectbl_ops)) {
  85                ret = PTR_ERR(sectbl_ops);
  86                goto cleanup_table;
  87        }
  88
  89        return ret;
  90
  91cleanup_table:
  92        unregister_pernet_subsys(&ip6table_security_net_ops);
  93        return ret;
  94}
  95
  96static void __exit ip6table_security_fini(void)
  97{
  98        xt_hook_unlink(&security_table, sectbl_ops);
  99        unregister_pernet_subsys(&ip6table_security_net_ops);
 100}
 101
 102module_init(ip6table_security_init);
 103module_exit(ip6table_security_fini);
 104