/* 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/netfilter_ipv6/ip6t_mac.h>#include <linux/netfilter_ipv6/ip6_tables.h>MODULE_LICENSE("GPL");MODULE_DESCRIPTION("MAC address matching module for IPv6");MODULE_AUTHOR("Netfilter Core Teaam <coreteam@netfilter.org>");static intmatch(const struct sk_buff *skb,      const struct net_device *in,      const struct net_device *out,      const void *matchinfo,      int offset,      const void *hdr,      u_int16_t datalen,      int *hotdrop){    const struct ip6t_mac_info *info = matchinfo;    /* Is mac pointer valid? */    return (skb->mac.raw >= skb->head	    && (skb->mac.raw + ETH_HLEN) <= skb->data	    /* If so, compare... */	    && ((memcmp(skb->mac.ethernet->h_source, info->srcaddr, ETH_ALEN)		== 0) ^ info->invert));}static intip6t_mac_checkentry(const char *tablename,		   const struct ip6t_ip6 *ip,		   void *matchinfo,		   unsigned int matchsize,		   unsigned int hook_mask){	if (hook_mask	    & ~((1 << NF_IP6_PRE_ROUTING) | (1 << NF_IP6_LOCAL_IN)		| (1 << NF_IP6_FORWARD))) {		printk("ip6t_mac: only valid for PRE_ROUTING, LOCAL_IN or"		       " FORWARD\n");		return 0;	}	if (matchsize != IP6T_ALIGN(sizeof(struct ip6t_mac_info)))		return 0;	return 1;}static struct ip6t_match mac_match = {	.name		= "mac",	.match		= &match,	.checkentry	= &ip6t_mac_checkentry,	.me		= THIS_MODULE,};static int __init init(void){	return ip6t_register_match(&mac_match);}static void __exit fini(void){	ip6t_unregister_match(&mac_match);}module_init(init);module_exit(fini);