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/* (C) 1999-2001 Michal Ludvig <michal@logix.cz>
*
* 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/if_ether.h>
#include <linux/if_packet.h>
#include <linux/netfilter/xt_pkttype.h>
#include <linux/netfilter/x_tables.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Michal Ludvig <michal@logix.cz>");
MODULE_DESCRIPTION("IP tables match to match on linklayer packet type");
MODULE_ALIAS("ipt_pkttype");
MODULE_ALIAS("ip6t_pkttype");
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_pkttype_info *info = matchinfo;
return (skb->pkt_type == info->pkttype) ^ info->invert;
}
static int checkentry(const char *tablename,
const void *ip,
void *matchinfo,
unsigned int matchsize,
unsigned int hook_mask)
{
if (matchsize != XT_ALIGN(sizeof(struct xt_pkttype_info)))
return 0;
return 1;
}
static struct xt_match pkttype_match = {
.name = "pkttype",
.match = &match,
.checkentry = &checkentry,
.me = THIS_MODULE,
};
static struct xt_match pkttype6_match = {
.name = "pkttype",
.match = &match,
.checkentry = &checkentry,
.me = THIS_MODULE,
};
static int __init init(void)
{
int ret;
ret = xt_register_match(AF_INET, &pkttype_match);
if (ret)
return ret;
ret = xt_register_match(AF_INET6, &pkttype6_match);
if (ret)
xt_unregister_match(AF_INET, &pkttype_match);
return ret;
}
static void __exit fini(void)
{
xt_unregister_match(AF_INET, &pkttype_match);
xt_unregister_match(AF_INET6, &pkttype6_match);
}
module_init(init);
module_exit(fini);
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