/* 
 * 'raw' table, which is the very first hooked in at PRE_ROUTING and LOCAL_OUT .
 *
 * Copyright (C) 2003 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
 */
#include <linux/module.h>
#include <linux/netfilter_ipv4/ip_tables.h>

#define RAW_VALID_HOOKS ((1 << NF_IP_PRE_ROUTING) | (1 << NF_IP_LOCAL_OUT))

/* Standard entry. */
struct ipt_standard
{
	struct ipt_entry entry;
	struct ipt_standard_target target;
};

struct ipt_error_target
{
	struct ipt_entry_target target;
	char errorname[IPT_FUNCTION_MAXNAMELEN];
};

struct ipt_error
{
	struct ipt_entry entry;
	struct ipt_error_target target;
};

static struct
{
	struct ipt_replace repl;
	struct ipt_standard entries[2];
	struct ipt_error term;
} initial_table __initdata
= { { "raw", RAW_VALID_HOOKS, 3,
      sizeof(struct ipt_standard) * 2 + sizeof(struct ipt_error),
      { [NF_IP_PRE_ROUTING] 0,
	[NF_IP_LOCAL_OUT] sizeof(struct ipt_standard) },
      { [NF_IP_PRE_ROUTING] 0,
	[NF_IP_LOCAL_OUT] sizeof(struct ipt_standard) },
      0, NULL, { } },
    {
	    /* PRE_ROUTING */
	    { { { { 0 }, { 0 }, { 0 }, { 0 }, "", "", { 0 }, { 0 }, 0, 0, 0 },
		0,
		sizeof(struct ipt_entry),
		sizeof(struct ipt_standard),
		0, { 0, 0 }, { } },
	      { { { { IPT_ALIGN(sizeof(struct ipt_standard_target)), "" } }, { } },
		-NF_ACCEPT - 1 } },
	    /* LOCAL_OUT */
	    { { { { 0 }, { 0 }, { 0 }, { 0 }, "", "", { 0 }, { 0 }, 0, 0, 0 },
		0,
		sizeof(struct ipt_entry),
		sizeof(struct ipt_standard),
		0, { 0, 0 }, { } },
	      { { { { IPT_ALIGN(sizeof(struct ipt_standard_target)), "" } }, { } },
		-NF_ACCEPT - 1 } }
    },
    /* ERROR */
    { { { { 0 }, { 0 }, { 0 }, { 0 }, "", "", { 0 }, { 0 }, 0, 0, 0 },
	0,
	sizeof(struct ipt_entry),
	sizeof(struct ipt_error),
	0, { 0, 0 }, { } },
      { { { { IPT_ALIGN(sizeof(struct ipt_error_target)), IPT_ERROR_TARGET } },
	  { } },
	"ERROR"
      }
    }
};

static struct ipt_table packet_raw = { 
	.name = "raw", 
	.table = &initial_table.repl,
	.valid_hooks =  RAW_VALID_HOOKS, 
	.lock = RW_LOCK_UNLOCKED, 
	.me = THIS_MODULE
};

/* The work comes in here from netfilter.c. */
static unsigned int
ipt_hook(unsigned int hook,
	 struct sk_buff **pskb,
	 const struct net_device *in,
	 const struct net_device *out,
	 int (*okfn)(struct sk_buff *))
{
	return ipt_do_table(pskb, hook, in, out, &packet_raw, NULL);
}

/* 'raw' is the very first table. */
static struct nf_hook_ops ipt_ops[] = {
	{
	  .hook = ipt_hook, 
	  .pf = PF_INET, 
	  .hooknum = NF_IP_PRE_ROUTING, 
	  .priority = NF_IP_PRI_RAW
	},
	{
	  .hook = ipt_hook, 
	  .pf = PF_INET, 
	  .hooknum = NF_IP_LOCAL_OUT, 
	  .priority = NF_IP_PRI_RAW
	},
};

static int __init init(void)
{
	int ret;

	/* Register table */
	ret = ipt_register_table(&packet_raw);
	if (ret < 0)
		return ret;

	/* Register hooks */
	ret = nf_register_hook(&ipt_ops[0]);
	if (ret < 0)
		goto cleanup_table;

	ret = nf_register_hook(&ipt_ops[1]);
	if (ret < 0)
		goto cleanup_hook0;

	return ret;

 cleanup_hook0:
	nf_unregister_hook(&ipt_ops[0]);
 cleanup_table:
	ipt_unregister_table(&packet_raw);

	return ret;
}

static void __exit fini(void)
{
	unsigned int i;

	for (i = 0; i < sizeof(ipt_ops)/sizeof(struct nf_hook_ops); i++)
		nf_unregister_hook(&ipt_ops[i]);

	ipt_unregister_table(&packet_raw);
}

module_init(init);
module_exit(fini);
MODULE_LICENSE("GPL");