[deliverable/linux.git] / net / ipv6 / netfilter / ip6table_filter.c

/*
 * This is the 1999 rewrite of IP Firewalling, aiming for kernel 2.3.x.
 *
 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
 * Copyright (C) 2000-2004 Netfilter Core Team <coreteam@netfilter.org>
 *
 * 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/moduleparam.h>
#include <linux/netfilter_ipv6/ip6_tables.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
MODULE_DESCRIPTION("ip6tables filter table");

#define FILTER_VALID_HOOKS ((1 << NF_INET_LOCAL_IN) | \
			    (1 << NF_INET_FORWARD) | \
			    (1 << NF_INET_LOCAL_OUT))

static struct
{
	struct ip6t_replace repl;
	struct ip6t_standard entries[3];
	struct ip6t_error term;
} initial_table __net_initdata = {
	.repl = {
		.name = "filter",
		.valid_hooks = FILTER_VALID_HOOKS,
		.num_entries = 4,
		.size = sizeof(struct ip6t_standard) * 3 + sizeof(struct ip6t_error),
		.hook_entry = {
			[NF_INET_LOCAL_IN] = 0,
			[NF_INET_FORWARD] = sizeof(struct ip6t_standard),
			[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2
		},
		.underflow = {
			[NF_INET_LOCAL_IN] = 0,
			[NF_INET_FORWARD] = sizeof(struct ip6t_standard),
			[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2
		},
	},
	.entries = {
		IP6T_STANDARD_INIT(NF_ACCEPT),	/* LOCAL_IN */
		IP6T_STANDARD_INIT(NF_ACCEPT),	/* FORWARD */
		IP6T_STANDARD_INIT(NF_ACCEPT),	/* LOCAL_OUT */
	},
	.term = IP6T_ERROR_INIT,		/* ERROR */
};

static const struct xt_table packet_filter = {
	.name		= "filter",
	.valid_hooks	= FILTER_VALID_HOOKS,
	.me		= THIS_MODULE,
	.af		= NFPROTO_IPV6,
};

/* The work comes in here from netfilter.c. */
static unsigned int
ip6t_in_hook(unsigned int hook,
		   struct sk_buff *skb,
		   const struct net_device *in,
		   const struct net_device *out,
		   int (*okfn)(struct sk_buff *))
{
	return ip6t_do_table(skb, hook, in, out,
			     dev_net(in)->ipv6.ip6table_filter);
}

static unsigned int
ip6t_local_out_hook(unsigned int hook,
		   struct sk_buff *skb,
		   const struct net_device *in,
		   const struct net_device *out,
		   int (*okfn)(struct sk_buff *))
{
#if 0
	/* root is playing with raw sockets. */
	if (skb->len < sizeof(struct iphdr) ||
	    ip_hdrlen(skb) < sizeof(struct iphdr)) {
		if (net_ratelimit())
			printk("ip6t_hook: happy cracking.\n");
		return NF_ACCEPT;
	}
#endif

	return ip6t_do_table(skb, hook, in, out,
			     dev_net(out)->ipv6.ip6table_filter);
}

static struct nf_hook_ops ip6t_ops[] __read_mostly = {
	{
		.hook		= ip6t_in_hook,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_LOCAL_IN,
		.priority	= NF_IP6_PRI_FILTER,
	},
	{
		.hook		= ip6t_in_hook,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_FORWARD,
		.priority	= NF_IP6_PRI_FILTER,
	},
	{
		.hook		= ip6t_local_out_hook,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_LOCAL_OUT,
		.priority	= NF_IP6_PRI_FILTER,
	},
};

/* Default to forward because I got too much mail already. */
static int forward = NF_ACCEPT;
module_param(forward, bool, 0000);

static int __net_init ip6table_filter_net_init(struct net *net)
{
	/* Register table */
	net->ipv6.ip6table_filter =
		ip6t_register_table(net, &packet_filter, &initial_table.repl);
	if (IS_ERR(net->ipv6.ip6table_filter))
		return PTR_ERR(net->ipv6.ip6table_filter);
	return 0;
}

static void __net_exit ip6table_filter_net_exit(struct net *net)
{
	ip6t_unregister_table(net, net->ipv6.ip6table_filter);
}

static struct pernet_operations ip6table_filter_net_ops = {
	.init = ip6table_filter_net_init,
	.exit = ip6table_filter_net_exit,
};

static int __init ip6table_filter_init(void)
{
	int ret;

	if (forward < 0 || forward > NF_MAX_VERDICT) {
		printk("iptables forward must be 0 or 1\n");
		return -EINVAL;
	}

	/* Entry 1 is the FORWARD hook */
	initial_table.entries[1].target.verdict = -forward - 1;

	ret = register_pernet_subsys(&ip6table_filter_net_ops);
	if (ret < 0)
		return ret;

	/* Register hooks */
	ret = nf_register_hooks(ip6t_ops, ARRAY_SIZE(ip6t_ops));
	if (ret < 0)
		goto cleanup_table;

	return ret;

 cleanup_table:
	unregister_pernet_subsys(&ip6table_filter_net_ops);
	return ret;
}

static void __exit ip6table_filter_fini(void)
{
	nf_unregister_hooks(ip6t_ops, ARRAY_SIZE(ip6t_ops));
	unregister_pernet_subsys(&ip6table_filter_net_ops);
}

module_init(ip6table_filter_init);
module_exit(ip6table_filter_fini);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* This is the 1999 rewrite of IP Firewalling, aiming for kernel 2.3.x.
	3	*
	4	* Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
	5	* Copyright (C) 2000-2004 Netfilter Core Team <coreteam@netfilter.org>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*/
	11
	12	#include <linux/module.h>
	13	#include <linux/moduleparam.h>
	14	#include <linux/netfilter_ipv6/ip6_tables.h>
	15
	16	MODULE_LICENSE("GPL");
	17	MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
	18	MODULE_DESCRIPTION("ip6tables filter table");
	19
6e23ae2a PM	20	#define FILTER_VALID_HOOKS ((1 << NF_INET_LOCAL_IN) \| \
	21	(1 << NF_INET_FORWARD) \| \
	22	(1 << NF_INET_LOCAL_OUT))
1da177e4	23
1da177e4 LT	24	static struct
	25	{
	26	struct ip6t_replace repl;
	27	struct ip6t_standard entries[3];
	28	struct ip6t_error term;
8280aa61	29	} initial_table __net_initdata = {
3c2ad469 PM	30	.repl = {
	31	.name = "filter",
	32	.valid_hooks = FILTER_VALID_HOOKS,
	33	.num_entries = 4,
	34	.size = sizeof(struct ip6t_standard) * 3 + sizeof(struct ip6t_error),
	35	.hook_entry = {
6e23ae2a PM	36	[NF_INET_LOCAL_IN] = 0,
	37	[NF_INET_FORWARD] = sizeof(struct ip6t_standard),
	38	[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2
3c2ad469 PM	39	},
3c2ad469 PM	40	.underflow = {
6e23ae2a PM	41	[NF_INET_LOCAL_IN] = 0,
	42	[NF_INET_FORWARD] = sizeof(struct ip6t_standard),
	43	[NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2
3c2ad469 PM	44	},
	45	},
	46	.entries = {
	47	IP6T_STANDARD_INIT(NF_ACCEPT), /* LOCAL_IN */
	48	IP6T_STANDARD_INIT(NF_ACCEPT), /* FORWARD */
	49	IP6T_STANDARD_INIT(NF_ACCEPT), /* LOCAL_OUT */
	50	},
	51	.term = IP6T_ERROR_INIT, /* ERROR */
1da177e4 LT	52	};
1da177e4 LT	53
35aad0ff	54	static const struct xt_table packet_filter = {
1da177e4 LT	55	.name = "filter",
1da177e4 LT	56	.valid_hooks = FILTER_VALID_HOOKS,
1da177e4	57	.me = THIS_MODULE,
f88e6a8a	58	.af = NFPROTO_IPV6,
1da177e4 LT	59	};
	60
	61	/* The work comes in here from netfilter.c. */
	62	static unsigned int
61d30158	63	ip6t_in_hook(unsigned int hook,
43de9dfe AD	64	struct sk_buff *skb,
	65	const struct net_device *in,
	66	const struct net_device *out,
	67	int (okfn)(struct sk_buff ))
	68	{
	69	return ip6t_do_table(skb, hook, in, out,
48dc7865	70	dev_net(in)->ipv6.ip6table_filter);
43de9dfe AD	71	}
43de9dfe AD	72
1da177e4 LT	73	static unsigned int
1da177e4 LT	74	ip6t_local_out_hook(unsigned int hook,
3db05fea	75	struct sk_buff *skb,
1da177e4 LT	76	const struct net_device *in,
	77	const struct net_device *out,
	78	int (okfn)(struct sk_buff ))
	79	{
	80	#if 0
	81	/* root is playing with raw sockets. */
3666ed1c JP	82	if (skb->len < sizeof(struct iphdr) \|\|
3666ed1c JP	83	ip_hdrlen(skb) < sizeof(struct iphdr)) {
1da177e4 LT	84	if (net_ratelimit())
	85	printk("ip6t_hook: happy cracking.\n");
	86	return NF_ACCEPT;
	87	}
	88	#endif
	89
43de9dfe	90	return ip6t_do_table(skb, hook, in, out,
48dc7865	91	dev_net(out)->ipv6.ip6table_filter);
1da177e4 LT	92	}
1da177e4 LT	93
1999414a	94	static struct nf_hook_ops ip6t_ops[] __read_mostly = {
1da177e4	95	{
61d30158	96	.hook = ip6t_in_hook,
1da177e4	97	.owner = THIS_MODULE,
24c232d8	98	.pf = NFPROTO_IPV6,
6e23ae2a	99	.hooknum = NF_INET_LOCAL_IN,
1da177e4 LT	100	.priority = NF_IP6_PRI_FILTER,
	101	},
	102	{
61d30158	103	.hook = ip6t_in_hook,
1da177e4	104	.owner = THIS_MODULE,
24c232d8	105	.pf = NFPROTO_IPV6,
6e23ae2a	106	.hooknum = NF_INET_FORWARD,
1da177e4 LT	107	.priority = NF_IP6_PRI_FILTER,
	108	},
	109	{
	110	.hook = ip6t_local_out_hook,
	111	.owner = THIS_MODULE,
24c232d8	112	.pf = NFPROTO_IPV6,
6e23ae2a	113	.hooknum = NF_INET_LOCAL_OUT,
1da177e4 LT	114	.priority = NF_IP6_PRI_FILTER,
	115	},
	116	};
	117
	118	/* Default to forward because I got too much mail already. */
	119	static int forward = NF_ACCEPT;
	120	module_param(forward, bool, 0000);
	121
8280aa61 AD	122	static int __net_init ip6table_filter_net_init(struct net *net)
	123	{
	124	/* Register table */
	125	net->ipv6.ip6table_filter =
	126	ip6t_register_table(net, &packet_filter, &initial_table.repl);
	127	if (IS_ERR(net->ipv6.ip6table_filter))
	128	return PTR_ERR(net->ipv6.ip6table_filter);
	129	return 0;
	130	}
	131
	132	static void __net_exit ip6table_filter_net_exit(struct net *net)
	133	{
f54e9367	134	ip6t_unregister_table(net, net->ipv6.ip6table_filter);
8280aa61 AD	135	}
	136
	137	static struct pernet_operations ip6table_filter_net_ops = {
	138	.init = ip6table_filter_net_init,
	139	.exit = ip6table_filter_net_exit,
	140	};
	141
65b4b4e8	142	static int __init ip6table_filter_init(void)
1da177e4 LT	143	{
	144	int ret;
	145
	146	if (forward < 0 \|\| forward > NF_MAX_VERDICT) {
	147	printk("iptables forward must be 0 or 1\n");
	148	return -EINVAL;
	149	}
	150
	151	/* Entry 1 is the FORWARD hook */
	152	initial_table.entries[1].target.verdict = -forward - 1;
	153
8280aa61 AD	154	ret = register_pernet_subsys(&ip6table_filter_net_ops);
	155	if (ret < 0)
	156	return ret;
1da177e4 LT	157
1da177e4 LT	158	/* Register hooks */
964ddaa1	159	ret = nf_register_hooks(ip6t_ops, ARRAY_SIZE(ip6t_ops));
1da177e4 LT	160	if (ret < 0)
	161	goto cleanup_table;
	162
1da177e4 LT	163	return ret;
1da177e4 LT	164
1da177e4	165	cleanup_table:
8280aa61	166	unregister_pernet_subsys(&ip6table_filter_net_ops);
1da177e4 LT	167	return ret;
	168	}
	169
65b4b4e8	170	static void __exit ip6table_filter_fini(void)
1da177e4	171	{
964ddaa1	172	nf_unregister_hooks(ip6t_ops, ARRAY_SIZE(ip6t_ops));
8280aa61	173	unregister_pernet_subsys(&ip6table_filter_net_ops);
1da177e4 LT	174	}
1da177e4 LT	175
65b4b4e8 AM	176	module_init(ip6table_filter_init);
65b4b4e8 AM	177	module_exit(ip6table_filter_fini);