// SPDX-License-Identifier: GPL-2.0-only/* Kernel module to match MAC address parameters. */ /* (C) 1999-2001 Paul `Rusty' Russell * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> */ #include <linux/module.h>#include <linux/skbuff.h>#include <linux/if_arp.h>#include <linux/if_ether.h>#include <linux/etherdevice.h> #include <linux/netfilter_ipv4.h>#include <linux/netfilter_ipv6.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("Xtables: MAC address match");MODULE_ALIAS("ipt_mac");MODULE_ALIAS("ip6t_mac"); static bool mac_mt(const struct sk_buff *skb, struct xt_action_param *par){	const struct xt_mac_info *info = par->matchinfo;	bool ret; 	if (skb->dev == NULL || skb->dev->type != ARPHRD_ETHER)		return false;	if (!skb_mac_header_was_set(skb) || skb_mac_header_len(skb) < ETH_HLEN)		return false;	ret  = ether_addr_equal(eth_hdr(skb)->h_source, info->srcaddr);	ret ^= info->invert;	return ret;} static struct xt_match mac_mt_reg[] __read_mostly = {	{		.name		= "mac",		.family		= NFPROTO_IPV4,		.match		= mac_mt,		.matchsize	= sizeof(struct xt_mac_info),		.hooks		= (1 << NF_INET_PRE_ROUTING) |				  (1 << NF_INET_LOCAL_IN) |				  (1 << NF_INET_FORWARD),		.me		= THIS_MODULE,	},	{		.name		= "mac",		.family		= NFPROTO_IPV6,		.match		= mac_mt,		.matchsize	= sizeof(struct xt_mac_info),		.hooks		= (1 << NF_INET_PRE_ROUTING) |				  (1 << NF_INET_LOCAL_IN) |				  (1 << NF_INET_FORWARD),		.me		= THIS_MODULE,	},}; static int __init mac_mt_init(void){	return xt_register_matches(mac_mt_reg, ARRAY_SIZE(mac_mt_reg));} static void __exit mac_mt_exit(void){	xt_unregister_matches(mac_mt_reg, ARRAY_SIZE(mac_mt_reg));} module_init(mac_mt_init);module_exit(mac_mt_exit);