/* Kernel module to match NFMARK values. */ /* (C) 1999-2001 Marc Boucher <marc@mbsi.ca> * * 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/netfilter/xt_mark.h>#include <linux/netfilter/x_tables.h> MODULE_LICENSE("GPL");MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");MODULE_DESCRIPTION("iptables mark matching module");MODULE_ALIAS("ipt_mark");MODULE_ALIAS("ip6t_mark"); static intmatch(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,      int *hotdrop){	const struct xt_mark_info *info = matchinfo; 	return ((skb->nfmark & info->mask) == info->mark) ^ info->invert;} static intcheckentry(const char *tablename,           const void *entry,	   const struct xt_match *match,           void *matchinfo,           unsigned int matchsize,           unsigned int hook_mask){	const struct xt_mark_info *minfo = matchinfo; 	if (minfo->mark > 0xffffffff || minfo->mask > 0xffffffff) {		printk(KERN_WARNING "mark: only supports 32bit mark\n");		return 0;	}	return 1;} static struct xt_match mark_match = {	.name		= "mark",	.match		= match,	.matchsize	= sizeof(struct xt_mark_info),	.checkentry	= checkentry,	.family		= AF_INET,	.me		= THIS_MODULE,}; static struct xt_match mark6_match = {	.name		= "mark",	.match		= match,	.matchsize	= sizeof(struct xt_mark_info),	.checkentry	= checkentry,	.family		= AF_INET6,	.me		= THIS_MODULE,}; static int __init xt_mark_init(void){	int ret;	ret = xt_register_match(&mark_match);	if (ret)		return ret; 	ret = xt_register_match(&mark6_match);	if (ret)		xt_unregister_match(&mark_match); 	return ret;} static void __exit xt_mark_fini(void){	xt_unregister_match(&mark_match);	xt_unregister_match(&mark6_match);} module_init(xt_mark_init);module_exit(xt_mark_fini);