net/netfilter/xt_mark.c

   1 /*
   2  *      xt_mark - Netfilter module to match NFMARK value
   3  *
   4  *      (C) 1999-2001 Marc Boucher <marc@mbsi.ca>
   5  *      Copyright © CC Computer Consultants GmbH, 2007 - 2008
   6  *      Jan Engelhardt <jengelh@medozas.de>
   7  *
   8  *      This program is free software; you can redistribute it and/or modify
   9  *      it under the terms of the GNU General Public License version 2 as
  10  *      published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/skbuff.h>
  15
  16 #include <linux/netfilter/xt_mark.h>
  17 #include <linux/netfilter/x_tables.h>
  18
  19 MODULE_LICENSE("GPL");
  20 MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
  21 MODULE_DESCRIPTION("Xtables: packet mark match");
  22 MODULE_ALIAS("ipt_mark");
  23 MODULE_ALIAS("ip6t_mark");
  24
  25 static bool
  26 mark_mt(const struct sk_buff *skb, const struct xt_match_param *par)
  27 {
  28         const struct xt_mark_mtinfo1 *info = par->matchinfo;
  29
  30         return ((skb->mark & info->mask) == info->mark) ^ info->invert;
  31 }
  32
  33 static struct xt_match mark_mt_reg __read_mostly = {
  34         .name           = "mark",
  35         .revision       = 1,
  36         .family         = NFPROTO_UNSPEC,
  37         .match          = mark_mt,
  38         .matchsize      = sizeof(struct xt_mark_mtinfo1),
  39         .me             = THIS_MODULE,
  40 };
  41
  42 static int __init mark_mt_init(void)
  43 {
  44         return xt_register_match(&mark_mt_reg);
  45 }
  46
  47 static void __exit mark_mt_exit(void)
  48 {
  49         xt_unregister_match(&mark_mt_reg);
  50 }
  51
  52 module_init(mark_mt_init);
  53 module_exit(mark_mt_exit);