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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/ipv6.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("Xtables: link layer packet type match");
MODULE_ALIAS("ipt_pkttype");
MODULE_ALIAS("ip6t_pkttype");
static bool
pkttype_mt(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,
bool *hotdrop)
{
const struct xt_pkttype_info *info = matchinfo;
u_int8_t type;
if (skb->pkt_type != PACKET_LOOPBACK)
type = skb->pkt_type;
else if (match->family == AF_INET &&
ipv4_is_multicast(ip_hdr(skb)->daddr))
type = PACKET_MULTICAST;
else if (match->family == AF_INET6 &&
ipv6_hdr(skb)->daddr.s6_addr[0] == 0xFF)
type = PACKET_MULTICAST;
else
type = PACKET_BROADCAST;
return (type == info->pkttype) ^ info->invert;
}
static struct xt_match pkttype_mt_reg[] __read_mostly = {
{
.name = "pkttype",
.family = AF_INET,
.match = pkttype_mt,
.matchsize = sizeof(struct xt_pkttype_info),
.me = THIS_MODULE,
},
{
.name = "pkttype",
.family = AF_INET6,
.match = pkttype_mt,
.matchsize = sizeof(struct xt_pkttype_info),
.me = THIS_MODULE,
},
};
static int __init pkttype_mt_init(void)
{
return xt_register_matches(pkttype_mt_reg, ARRAY_SIZE(pkttype_mt_reg));
}
static void __exit pkttype_mt_exit(void)
{
xt_unregister_matches(pkttype_mt_reg, ARRAY_SIZE(pkttype_mt_reg));
}
module_init(pkttype_mt_init);
module_exit(pkttype_mt_exit);
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