blob: 34ba150bfe5d9089e65301a47648a31747de73ba [file] [log] [blame]
/* Kernel module to match EUI64 address parameters. */
/* (C) 2001-2002 Andras Kis-Szabo <kisza@sch.bme.hu>
*
* 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/ipv6.h>
#include <linux/if_ether.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
MODULE_DESCRIPTION("IPv6 EUI64 address checking match");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Andras Kis-Szabo <kisza@sch.bme.hu>");
static bool
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,
bool *hotdrop)
{
unsigned char eui64[8];
int i = 0;
if (!(skb_mac_header(skb) >= skb->head &&
skb_mac_header(skb) + ETH_HLEN <= skb->data) &&
offset != 0) {
*hotdrop = true;
return false;
}
memset(eui64, 0, sizeof(eui64));
if (eth_hdr(skb)->h_proto == htons(ETH_P_IPV6)) {
if (ipv6_hdr(skb)->version == 0x6) {
memcpy(eui64, eth_hdr(skb)->h_source, 3);
memcpy(eui64 + 5, eth_hdr(skb)->h_source + 3, 3);
eui64[3] = 0xff;
eui64[4] = 0xfe;
eui64[0] |= 0x02;
i = 0;
while (ipv6_hdr(skb)->saddr.s6_addr[8 + i] == eui64[i]
&& i < 8)
i++;
if (i == 8)
return true;
}
}
return false;
}
static struct xt_match eui64_match __read_mostly = {
.name = "eui64",
.family = AF_INET6,
.match = match,
.matchsize = sizeof(int),
.hooks = (1 << NF_IP6_PRE_ROUTING) | (1 << NF_IP6_LOCAL_IN) |
(1 << NF_IP6_FORWARD),
.me = THIS_MODULE,
};
static int __init ip6t_eui64_init(void)
{
return xt_register_match(&eui64_match);
}
static void __exit ip6t_eui64_fini(void)
{
xt_unregister_match(&eui64_match);
}
module_init(ip6t_eui64_init);
module_exit(ip6t_eui64_fini);