[mirror_ubuntu-artful-kernel.git] / net / ipv4 / netfilter / arptable_filter.c

/*
 * Filtering ARP tables module.
 *
 * Copyright (C) 2002 David S. Miller (davem@redhat.com)
 *
 */

#include <linux/module.h>
#include <linux/netfilter_arp/arp_tables.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
MODULE_DESCRIPTION("arptables filter table");

#define FILTER_VALID_HOOKS ((1 << NF_ARP_IN) | (1 << NF_ARP_OUT) | \
			   (1 << NF_ARP_FORWARD))

static const struct
{
	struct arpt_replace repl;
	struct arpt_standard entries[3];
	struct arpt_error term;
} initial_table __net_initdata = {
	.repl = {
		.name = "filter",
		.valid_hooks = FILTER_VALID_HOOKS,
		.num_entries = 4,
		.size = sizeof(struct arpt_standard) * 3 + sizeof(struct arpt_error),
		.hook_entry = {
			[NF_ARP_IN] = 0,
			[NF_ARP_OUT] = sizeof(struct arpt_standard),
			[NF_ARP_FORWARD] = 2 * sizeof(struct arpt_standard),
		},
		.underflow = {
			[NF_ARP_IN] = 0,
			[NF_ARP_OUT] = sizeof(struct arpt_standard),
			[NF_ARP_FORWARD] = 2 * sizeof(struct arpt_standard),
		},
	},
	.entries = {
		ARPT_STANDARD_INIT(NF_ACCEPT),	/* ARP_IN */
		ARPT_STANDARD_INIT(NF_ACCEPT),	/* ARP_OUT */
		ARPT_STANDARD_INIT(NF_ACCEPT),	/* ARP_FORWARD */
	},
	.term = ARPT_ERROR_INIT,
};

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

/* The work comes in here from netfilter.c */
static unsigned int arpt_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 arpt_do_table(skb, hook, in, out,
			     dev_net(in)->ipv4.arptable_filter);
}

static unsigned int arpt_out_hook(unsigned int hook,
				  struct sk_buff *skb,
				  const struct net_device *in,
				  const struct net_device *out,
				  int (*okfn)(struct sk_buff *))
{
	return arpt_do_table(skb, hook, in, out,
			     dev_net(out)->ipv4.arptable_filter);
}

static struct nf_hook_ops arpt_ops[] __read_mostly = {
	{
		.hook		= arpt_in_hook,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_ARP,
		.hooknum	= NF_ARP_IN,
		.priority	= NF_IP_PRI_FILTER,
	},
	{
		.hook		= arpt_out_hook,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_ARP,
		.hooknum	= NF_ARP_OUT,
		.priority	= NF_IP_PRI_FILTER,
	},
	{
		.hook		= arpt_in_hook,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_ARP,
		.hooknum	= NF_ARP_FORWARD,
		.priority	= NF_IP_PRI_FILTER,
	},
};

static int __net_init arptable_filter_net_init(struct net *net)
{
	/* Register table */
	net->ipv4.arptable_filter =
		arpt_register_table(net, &packet_filter, &initial_table.repl);
	if (IS_ERR(net->ipv4.arptable_filter))
		return PTR_ERR(net->ipv4.arptable_filter);
	return 0;
}

static void __net_exit arptable_filter_net_exit(struct net *net)
{
	arpt_unregister_table(net->ipv4.arptable_filter);
}

static struct pernet_operations arptable_filter_net_ops = {
	.init = arptable_filter_net_init,
	.exit = arptable_filter_net_exit,
};

static int __init arptable_filter_init(void)
{
	int ret;

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

	ret = nf_register_hooks(arpt_ops, ARRAY_SIZE(arpt_ops));
	if (ret < 0)
		goto cleanup_table;
	return ret;

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

static void __exit arptable_filter_fini(void)
{
	nf_unregister_hooks(arpt_ops, ARRAY_SIZE(arpt_ops));
	unregister_pernet_subsys(&arptable_filter_net_ops);
}

module_init(arptable_filter_init);
module_exit(arptable_filter_fini);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Filtering ARP tables module.
	3	*
	4	* Copyright (C) 2002 David S. Miller (davem@redhat.com)
	5	*
	6	*/
	7
	8	#include <linux/module.h>
	9	#include <linux/netfilter_arp/arp_tables.h>
	10
	11	MODULE_LICENSE("GPL");
	12	MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
	13	MODULE_DESCRIPTION("arptables filter table");
	14
	15	#define FILTER_VALID_HOOKS ((1 << NF_ARP_IN) \| (1 << NF_ARP_OUT) \| \
	16	(1 << NF_ARP_FORWARD))
	17
35aad0ff	18	static const struct
1da177e4 LT	19	{
	20	struct arpt_replace repl;
	21	struct arpt_standard entries[3];
	22	struct arpt_error term;
9ea0cb26	23	} initial_table __net_initdata = {
3c2ad469 PM	24	.repl = {
	25	.name = "filter",
	26	.valid_hooks = FILTER_VALID_HOOKS,
	27	.num_entries = 4,
	28	.size = sizeof(struct arpt_standard) * 3 + sizeof(struct arpt_error),
	29	.hook_entry = {
	30	[NF_ARP_IN] = 0,
	31	[NF_ARP_OUT] = sizeof(struct arpt_standard),
	32	[NF_ARP_FORWARD] = 2 * sizeof(struct arpt_standard),
	33	},
	34	.underflow = {
	35	[NF_ARP_IN] = 0,
	36	[NF_ARP_OUT] = sizeof(struct arpt_standard),
	37	[NF_ARP_FORWARD] = 2 * sizeof(struct arpt_standard),
	38	},
	39	},
	40	.entries = {
	41	ARPT_STANDARD_INIT(NF_ACCEPT), /* ARP_IN */
	42	ARPT_STANDARD_INIT(NF_ACCEPT), /* ARP_OUT */
	43	ARPT_STANDARD_INIT(NF_ACCEPT), /* ARP_FORWARD */
	44	},
	45	.term = ARPT_ERROR_INIT,
1da177e4 LT	46	};
1da177e4 LT	47
35aad0ff	48	static const struct xt_table packet_filter = {
1da177e4 LT	49	.name = "filter",
1da177e4 LT	50	.valid_hooks = FILTER_VALID_HOOKS,
1da177e4	51	.me = THIS_MODULE,
ee999d8b	52	.af = NFPROTO_ARP,
1da177e4 LT	53	};
	54
	55	/* The work comes in here from netfilter.c */
3918fed5 AD	56	static unsigned int arpt_in_hook(unsigned int hook,
	57	struct sk_buff *skb,
	58	const struct net_device *in,
	59	const struct net_device *out,
	60	int (okfn)(struct sk_buff ))
1da177e4	61	{
3918fed5 AD	62	return arpt_do_table(skb, hook, in, out,
	63	dev_net(in)->ipv4.arptable_filter);
	64	}
	65
	66	static unsigned int arpt_out_hook(unsigned int hook,
	67	struct sk_buff *skb,
	68	const struct net_device *in,
	69	const struct net_device *out,
	70	int (okfn)(struct sk_buff ))
	71	{
	72	return arpt_do_table(skb, hook, in, out,
	73	dev_net(out)->ipv4.arptable_filter);
	74	}
	75
1999414a	76	static struct nf_hook_ops arpt_ops[] __read_mostly = {
1da177e4	77	{
3918fed5	78	.hook = arpt_in_hook,
1da177e4	79	.owner = THIS_MODULE,
ee999d8b	80	.pf = NFPROTO_ARP,
1da177e4	81	.hooknum = NF_ARP_IN,
c2f9c683	82	.priority = NF_IP_PRI_FILTER,
1da177e4 LT	83	},
1da177e4 LT	84	{
3918fed5	85	.hook = arpt_out_hook,
1da177e4	86	.owner = THIS_MODULE,
ee999d8b	87	.pf = NFPROTO_ARP,
1da177e4	88	.hooknum = NF_ARP_OUT,
c2f9c683	89	.priority = NF_IP_PRI_FILTER,
1da177e4 LT	90	},
1da177e4 LT	91	{
19223f26	92	.hook = arpt_in_hook,
1da177e4	93	.owner = THIS_MODULE,
ee999d8b	94	.pf = NFPROTO_ARP,
1da177e4	95	.hooknum = NF_ARP_FORWARD,
c2f9c683	96	.priority = NF_IP_PRI_FILTER,
1da177e4 LT	97	},
	98	};
	99
9ea0cb26 AD	100	static int __net_init arptable_filter_net_init(struct net *net)
	101	{
	102	/* Register table */
	103	net->ipv4.arptable_filter =
	104	arpt_register_table(net, &packet_filter, &initial_table.repl);
	105	if (IS_ERR(net->ipv4.arptable_filter))
	106	return PTR_ERR(net->ipv4.arptable_filter);
	107	return 0;
	108	}
	109
	110	static void __net_exit arptable_filter_net_exit(struct net *net)
	111	{
	112	arpt_unregister_table(net->ipv4.arptable_filter);
	113	}
	114
	115	static struct pernet_operations arptable_filter_net_ops = {
	116	.init = arptable_filter_net_init,
	117	.exit = arptable_filter_net_exit,
	118	};
	119
65b4b4e8	120	static int __init arptable_filter_init(void)
1da177e4	121	{
964ddaa1	122	int ret;
1da177e4	123
9ea0cb26 AD	124	ret = register_pernet_subsys(&arptable_filter_net_ops);
	125	if (ret < 0)
	126	return ret;
1da177e4	127
964ddaa1 PM	128	ret = nf_register_hooks(arpt_ops, ARRAY_SIZE(arpt_ops));
	129	if (ret < 0)
	130	goto cleanup_table;
1da177e4 LT	131	return ret;
1da177e4 LT	132
964ddaa1	133	cleanup_table:
9ea0cb26	134	unregister_pernet_subsys(&arptable_filter_net_ops);
1da177e4 LT	135	return ret;
	136	}
	137
65b4b4e8	138	static void __exit arptable_filter_fini(void)
1da177e4	139	{
964ddaa1	140	nf_unregister_hooks(arpt_ops, ARRAY_SIZE(arpt_ops));
9ea0cb26	141	unregister_pernet_subsys(&arptable_filter_net_ops);
1da177e4 LT	142	}
1da177e4 LT	143
65b4b4e8 AM	144	module_init(arptable_filter_init);
65b4b4e8 AM	145	module_exit(arptable_filter_fini);