/* *  ebtable_nat * *	Authors: *	Bart De Schuymer <bdschuym@pandora.be> * *  April, 2002 * */#include <linux/netfilter_bridge/ebtables.h>#include <linux/module.h>#define NAT_VALID_HOOKS ((1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_LOCAL_OUT) | \   (1 << NF_BR_POST_ROUTING))static struct ebt_entries initial_chains[] ={	{		.name	= "PREROUTING",		.policy	= EBT_ACCEPT,	},	{		.name	= "OUTPUT",		.policy	= EBT_ACCEPT,	},	{		.name	= "POSTROUTING",		.policy	= EBT_ACCEPT,	}};static struct ebt_replace initial_table ={	.name		= "nat",	.valid_hooks	= NAT_VALID_HOOKS,	.entries_size	= 3 * sizeof(struct ebt_entries),	.hook_entry	= {		[NF_BR_PRE_ROUTING]	= &initial_chains[0],		[NF_BR_LOCAL_OUT]	= &initial_chains[1],		[NF_BR_POST_ROUTING]	= &initial_chains[2],	},	.entries	= (char *)initial_chains,};static int check(const struct ebt_table_info *info, unsigned int valid_hooks){	if (valid_hooks & ~NAT_VALID_HOOKS)		return -EINVAL;	return 0;}static struct ebt_table frame_nat ={	.name		= "nat",	.table		= &initial_table,	.valid_hooks	= NAT_VALID_HOOKS,	.lock		= RW_LOCK_UNLOCKED,	.check		= check,	.me		= THIS_MODULE,};static unsigned intebt_nat_dst(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_nat);}static unsigned intebt_nat_src(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_nat);}static struct nf_hook_ops ebt_ops_nat[] = {	{		.hook		= ebt_nat_dst,		.owner		= THIS_MODULE,		.pf		= PF_BRIDGE,		.hooknum	= NF_BR_LOCAL_OUT,		.priority	= NF_BR_PRI_NAT_DST_OTHER,	},	{		.hook		= ebt_nat_src,		.owner		= THIS_MODULE,		.pf		= PF_BRIDGE,		.hooknum	= NF_BR_POST_ROUTING,		.priority	= NF_BR_PRI_NAT_SRC,	},	{		.hook		= ebt_nat_dst,		.owner		= THIS_MODULE,		.pf		= PF_BRIDGE,		.hooknum	= NF_BR_PRE_ROUTING,		.priority	= NF_BR_PRI_NAT_DST_BRIDGED,	},};static int __init init(void){	int i, ret, j;	ret = ebt_register_table(&frame_nat);	if (ret < 0)		return ret;	for (i = 0; i < ARRAY_SIZE(ebt_ops_nat); i++)		if ((ret = nf_register_hook(&ebt_ops_nat[i])) < 0)			goto cleanup;	return ret;cleanup:	for (j = 0; j < i; j++)		nf_unregister_hook(&ebt_ops_nat[j]);	ebt_unregister_table(&frame_nat);	return ret;}static void __exit fini(void){	int i;	for (i = 0; i < ARRAY_SIZE(ebt_ops_nat); i++)		nf_unregister_hook(&ebt_ops_nat[i]);	ebt_unregister_table(&frame_nat);}module_init(init);module_exit(fini);MODULE_LICENSE("GPL");