/* *  ebtable_filter * *	Authors: *	Bart De Schuymer <bdschuym@pandora.be> * *  April, 2002 * */#include <linux/netfilter_bridge/ebtables.h>#include <linux/module.h>#define FILTER_VALID_HOOKS ((1 << NF_BR_LOCAL_IN) | (1 << NF_BR_FORWARD) | \   (1 << NF_BR_LOCAL_OUT))static struct ebt_entries initial_chains[] ={	{		.name	= "INPUT",		.policy	= EBT_ACCEPT,	},	{		.name	= "FORWARD",		.policy	= EBT_ACCEPT,	},	{		.name	= "OUTPUT",		.policy	= EBT_ACCEPT,	},};static struct ebt_replace initial_table ={	.name		= "filter",	.valid_hooks	= FILTER_VALID_HOOKS,	.entries_size	= 3 * sizeof(struct ebt_entries),	.hook_entry	= {		[NF_BR_LOCAL_IN]	= &initial_chains[0],		[NF_BR_FORWARD]		= &initial_chains[1],		[NF_BR_LOCAL_OUT]	= &initial_chains[2],	},	.entries	= (char *)initial_chains,};static int check(const struct ebt_table_info *info, unsigned int valid_hooks){	if (valid_hooks & ~FILTER_VALID_HOOKS)		return -EINVAL;	return 0;}static struct ebt_table frame_filter ={ 	.name		= "filter",	.table		= &initial_table,	.valid_hooks	= FILTER_VALID_HOOKS, 	.lock		= RW_LOCK_UNLOCKED,	.check		= check,	.me		= THIS_MODULE,};static unsigned intebt_hook (unsigned int hook, struct sk_buff **pskb, const struct net_device *in,   const struct net_device *out, int (*okfn)(struct sk_buff *)){	return ebt_do_table(hook, pskb, in, out, &frame_filter);}static struct nf_hook_ops ebt_ops_filter[] = {	{		.hook		= ebt_hook,		.owner		= THIS_MODULE,		.pf		= PF_BRIDGE,		.hooknum	= NF_BR_LOCAL_IN,		.priority	= NF_BR_PRI_FILTER_BRIDGED,	},	{		.hook		= ebt_hook,		.owner		= THIS_MODULE,		.pf		= PF_BRIDGE,		.hooknum	= NF_BR_FORWARD,		.priority	= NF_BR_PRI_FILTER_BRIDGED,	},	{		.hook		= ebt_hook,		.owner		= THIS_MODULE,		.pf		= PF_BRIDGE,		.hooknum	= NF_BR_LOCAL_OUT,		.priority	= NF_BR_PRI_FILTER_OTHER,	},};static int __init init(void){	int i, j, ret;	ret = ebt_register_table(&frame_filter);	if (ret < 0)		return ret;	for (i = 0; i < ARRAY_SIZE(ebt_ops_filter); i++)		if ((ret = nf_register_hook(&ebt_ops_filter[i])) < 0)			goto cleanup;	return ret;cleanup:	for (j = 0; j < i; j++)		nf_unregister_hook(&ebt_ops_filter[j]);	ebt_unregister_table(&frame_filter);	return ret;}static void __exit fini(void){	int i;	for (i = 0; i < ARRAY_SIZE(ebt_ops_filter); i++)		nf_unregister_hook(&ebt_ops_filter[i]);	ebt_unregister_table(&frame_filter);}module_init(init);module_exit(fini);MODULE_LICENSE("GPL");