/* IP tables module for matching the routing realm
   *

   * (C) 2003 by Sampsa Ranta <sampsa@netsonic.fi>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   */
  
  #include <linux/module.h>
  #include <linux/skbuff.h>
  #include <linux/netdevice.h>
  #include <net/route.h>

  #include <linux/netfilter_ipv4.h>
  #include <linux/netfilter/xt_realm.h>
  #include <linux/netfilter/x_tables.h>

  
  MODULE_AUTHOR("Sampsa Ranta <sampsa@netsonic.fi>");
  MODULE_LICENSE("GPL");

  MODULE_DESCRIPTION("Xtables: Routing realm match");

  MODULE_ALIAS("ipt_realm");

  static bool

  realm_mt(const struct sk_buff *skb, struct xt_action_param *par)

  {

  	const struct xt_realm_info *info = par->matchinfo;

  	const struct dst_entry *dst = skb_dst(skb);

  	return (info->id == (dst->tclassid & info->mask)) ^ info->invert;
  }

  static struct xt_match realm_mt_reg __read_mostly = {

  	.name		= "realm",

  	.match		= realm_mt,

  	.matchsize	= sizeof(struct xt_realm_info),

  	.hooks		= (1 << NF_INET_POST_ROUTING) | (1 << NF_INET_FORWARD) |
  			  (1 << NF_INET_LOCAL_OUT) | (1 << NF_INET_LOCAL_IN),

  	.family		= NFPROTO_UNSPEC,

  	.me		= THIS_MODULE
  };

  static int __init realm_mt_init(void)

  {

  	return xt_register_match(&realm_mt_reg);

  }

  static void __exit realm_mt_exit(void)

  {

  	xt_unregister_match(&realm_mt_reg);

  }

  module_init(realm_mt_init);
  module_exit(realm_mt_exit);