1/* Kernel module to match MAC address parameters. */ 2 3/* (C) 1999-2001 Paul `Rusty' Russell 4 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10 11#include <linux/module.h> 12#include <linux/skbuff.h> 13#include <linux/if_arp.h> 14#include <linux/if_ether.h> 15#include <linux/etherdevice.h> 16 17#include <linux/netfilter_ipv4.h> 18#include <linux/netfilter_ipv6.h> 19#include <linux/netfilter/xt_mac.h> 20#include <linux/netfilter/x_tables.h> 21 22MODULE_LICENSE("GPL"); 23MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); 24MODULE_DESCRIPTION("Xtables: MAC address match"); 25MODULE_ALIAS("ipt_mac"); 26MODULE_ALIAS("ip6t_mac"); 27 28static bool mac_mt(const struct sk_buff *skb, struct xt_action_param *par) 29{ 30 const struct xt_mac_info *info = par->matchinfo; 31 bool ret; 32 33 if (skb->dev == NULL || skb->dev->type != ARPHRD_ETHER) 34 return false; 35 if (skb_mac_header(skb) < skb->head) 36 return false; 37 if (skb_mac_header(skb) + ETH_HLEN > skb->data) 38 return false; 39 ret = compare_ether_addr(eth_hdr(skb)->h_source, info->srcaddr) == 0; 40 ret ^= info->invert; 41 return ret; 42} 43 44static struct xt_match mac_mt_reg __read_mostly = { 45 .name = "mac", 46 .revision = 0, 47 .family = NFPROTO_UNSPEC, 48 .match = mac_mt, 49 .matchsize = sizeof(struct xt_mac_info), 50 .hooks = (1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_IN) | 51 (1 << NF_INET_FORWARD), 52 .me = THIS_MODULE, 53}; 54 55static int __init mac_mt_init(void) 56{ 57 return xt_register_match(&mac_mt_reg); 58} 59 60static void __exit mac_mt_exit(void) 61{ 62 xt_unregister_match(&mac_mt_reg); 63} 64 65module_init(mac_mt_init); 66module_exit(mac_mt_exit); 67