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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/in.h>
#include <linux/ip.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 struct xt_match *match,
const void *matchinfo,
int offset,
unsigned int protoff,
int *hotdrop)
{
u_int8_t type;
const struct xt_pkttype_info *info = matchinfo;
if (skb->pkt_type == PACKET_LOOPBACK)
type = (MULTICAST(skb->nh.iph->daddr)
? PACKET_MULTICAST
: PACKET_BROADCAST);
else
type = skb->pkt_type;
return (type == info->pkttype) ^ info->invert;
}
static struct xt_match xt_pkttype_match[] = {
{
.name = "pkttype",
.family = AF_INET,
.match = match,
.matchsize = sizeof(struct xt_pkttype_info),
.me = THIS_MODULE,
},
{
.name = "pkttype",
.family = AF_INET6,
.match = match,
.matchsize = sizeof(struct xt_pkttype_info),
.me = THIS_MODULE,
},
};
static int __init xt_pkttype_init(void)
{
return xt_register_matches(xt_pkttype_match,
ARRAY_SIZE(xt_pkttype_match));
}
static void __exit xt_pkttype_fini(void)
{
xt_unregister_matches(xt_pkttype_match, ARRAY_SIZE(xt_pkttype_match));
}
module_init(xt_pkttype_init);
module_exit(xt_pkttype_fini);
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