/* This kernel module matches connection mark values set by the
* CONNMARK target
*
* Copyright (C) 2002,2004 MARA Systems AB <http://www.marasystems.com>
* by Henrik Nordstrom <hno@marasystems.com>
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/module.h>
#include <linux/skbuff.h>
MODULE_AUTHOR("Henrik Nordstrom <hno@marasytems.com>");
MODULE_DESCRIPTION("IP tables connmark match module");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_connmark");
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_connmark.h>
#include <net/netfilter/nf_conntrack_compat.h>
static int
match(const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const void *matchinfo,
int offset,
unsigned int protoff,
int *hotdrop)
{
const struct xt_connmark_info *info = matchinfo;
u_int32_t ctinfo;
const u_int32_t *ctmark = nf_ct_get_mark(skb, &ctinfo);
if (!ctmark)
return 0;
return (((*ctmark) & info->mask) == info->mark) ^ info->invert;
}
checkentry(const char *tablename,
const void *ip,
void *matchinfo,
unsigned int matchsize,
unsigned int hook_mask)
struct xt_connmark_info *cm =
(struct xt_connmark_info *)matchinfo;
if (matchsize != XT_ALIGN(sizeof(struct xt_connmark_info)))
if (cm->mark > 0xffffffff || cm->mask > 0xffffffff) {
printk(KERN_WARNING "connmark: only support 32bit mark\n");
return 1;
static struct xt_match connmark_match = {
.name = "connmark",
.match = &match,
.checkentry = &checkentry,
.me = THIS_MODULE
};
static struct xt_match connmark6_match = {
static int __init init(void)
int ret;
need_conntrack();
ret = xt_register_match(AF_INET, &connmark_match);
if (ret)
return ret;
ret = xt_register_match(AF_INET6, &connmark6_match);
xt_unregister_match(AF_INET, &connmark_match);
static void __exit fini(void)
xt_unregister_match(AF_INET6, &connmark6_match);
module_init(init);
module_exit(fini);