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/* Kernel module to match MAC address parameters. */
/* (C) 1999-2001 Paul `Rusty' Russell
* (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
*
* 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/etherdevice.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter/xt_mac.h>
#include <linux/netfilter/x_tables.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
MODULE_DESCRIPTION("iptables mac matching module");
MODULE_ALIAS("ipt_mac");
MODULE_ALIAS("ip6t_mac");
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_mac_info *info = matchinfo;
/* Is mac pointer valid? */
return (skb->mac.raw >= skb->head
&& (skb->mac.raw + ETH_HLEN) <= skb->data
/* If so, compare... */
&& ((!compare_ether_addr(eth_hdr(skb)->h_source, info->srcaddr))
^ info->invert));
}
static int
ipt_mac_checkentry(const char *tablename,
const void *inf,
void *matchinfo,
unsigned int matchsize,
unsigned int hook_mask)
{
/* FORWARD isn't always valid, but it's nice to be able to do --RR */
if (hook_mask
& ~((1 << NF_IP_PRE_ROUTING) | (1 << NF_IP_LOCAL_IN)
| (1 << NF_IP_FORWARD))) {
printk("xt_mac: only valid for PRE_ROUTING, LOCAL_IN or FORWARD.\n");
return 0;
}
if (matchsize != XT_ALIGN(sizeof(struct xt_mac_info)))
return 0;
return 1;
}
static struct xt_match mac_match = {
.name = "mac",
.match = &match,
.checkentry = &ipt_mac_checkentry,
.me = THIS_MODULE,
};
static struct xt_match mac6_match = {
.name = "mac",
.match = &match,
.checkentry = &ipt_mac_checkentry,
.me = THIS_MODULE,
};
static int __init init(void)
{
int ret;
ret = xt_register_match(AF_INET, &mac_match);
if (ret)
return ret;
ret = xt_register_match(AF_INET6, &mac6_match);
if (ret)
xt_unregister_match(AF_INET, &mac_match);
return ret;
}
static void __exit fini(void)
{
xt_unregister_match(AF_INET, &mac_match);
xt_unregister_match(AF_INET6, &mac6_match);
}
module_init(init);
module_exit(fini);
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