[linux.git] / net / netfilter / xt_nat.c

/*
 * (C) 1999-2001 Paul `Rusty' Russell
 * (C) 2002-2006 Netfilter Core Team <[email protected]>
 * (C) 2011 Patrick McHardy <[email protected]>
 *
 * 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/skbuff.h>
#include <linux/netfilter.h>
#include <linux/netfilter/x_tables.h>
#include <net/netfilter/nf_nat_core.h>

static int xt_nat_checkentry_v0(const struct xt_tgchk_param *par)
{
	const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo;

	if (mr->rangesize != 1) {
		pr_info("%s: multiple ranges no longer supported\n",
			par->target->name);
		return -EINVAL;
	}
	return 0;
}

static void xt_nat_convert_range(struct nf_nat_range *dst,
				 const struct nf_nat_ipv4_range *src)
{
	memset(&dst->min_addr, 0, sizeof(dst->min_addr));
	memset(&dst->max_addr, 0, sizeof(dst->max_addr));

	dst->flags	 = src->flags;
	dst->min_addr.ip = src->min_ip;
	dst->max_addr.ip = src->max_ip;
	dst->min_proto	 = src->min;
	dst->max_proto	 = src->max;
}

static unsigned int
xt_snat_target_v0(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo;
	struct nf_nat_range range;
	enum ip_conntrack_info ctinfo;
	struct nf_conn *ct;

	ct = nf_ct_get(skb, &ctinfo);
	NF_CT_ASSERT(ct != NULL &&
		     (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED ||
		      ctinfo == IP_CT_RELATED_REPLY));

	xt_nat_convert_range(&range, &mr->range[0]);
	return nf_nat_setup_info(ct, &range, NF_NAT_MANIP_SRC);
}

static unsigned int
xt_dnat_target_v0(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo;
	struct nf_nat_range range;
	enum ip_conntrack_info ctinfo;
	struct nf_conn *ct;

	ct = nf_ct_get(skb, &ctinfo);
	NF_CT_ASSERT(ct != NULL &&
		     (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED));

	xt_nat_convert_range(&range, &mr->range[0]);
	return nf_nat_setup_info(ct, &range, NF_NAT_MANIP_DST);
}

static unsigned int
xt_snat_target_v1(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct nf_nat_range *range = par->targinfo;
	enum ip_conntrack_info ctinfo;
	struct nf_conn *ct;

	ct = nf_ct_get(skb, &ctinfo);
	NF_CT_ASSERT(ct != NULL &&
		     (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED ||
		      ctinfo == IP_CT_RELATED_REPLY));

	return nf_nat_setup_info(ct, range, NF_NAT_MANIP_SRC);
}

static unsigned int
xt_dnat_target_v1(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct nf_nat_range *range = par->targinfo;
	enum ip_conntrack_info ctinfo;
	struct nf_conn *ct;

	ct = nf_ct_get(skb, &ctinfo);
	NF_CT_ASSERT(ct != NULL &&
		     (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED));

	return nf_nat_setup_info(ct, range, NF_NAT_MANIP_DST);
}

static struct xt_target xt_nat_target_reg[] __read_mostly = {
	{
		.name		= "SNAT",
		.revision	= 0,
		.checkentry	= xt_nat_checkentry_v0,
		.target		= xt_snat_target_v0,
		.targetsize	= sizeof(struct nf_nat_ipv4_multi_range_compat),
		.family		= NFPROTO_IPV4,
		.table		= "nat",
		.hooks		= (1 << NF_INET_POST_ROUTING) |
				  (1 << NF_INET_LOCAL_IN),
		.me		= THIS_MODULE,
	},
	{
		.name		= "DNAT",
		.revision	= 0,
		.checkentry	= xt_nat_checkentry_v0,
		.target		= xt_dnat_target_v0,
		.targetsize	= sizeof(struct nf_nat_ipv4_multi_range_compat),
		.family		= NFPROTO_IPV4,
		.table		= "nat",
		.hooks		= (1 << NF_INET_PRE_ROUTING) |
				  (1 << NF_INET_LOCAL_OUT),
		.me		= THIS_MODULE,
	},
	{
		.name		= "SNAT",
		.revision	= 1,
		.target		= xt_snat_target_v1,
		.targetsize	= sizeof(struct nf_nat_range),
		.table		= "nat",
		.hooks		= (1 << NF_INET_POST_ROUTING) |
				  (1 << NF_INET_LOCAL_IN),
		.me		= THIS_MODULE,
	},
	{
		.name		= "DNAT",
		.revision	= 1,
		.target		= xt_dnat_target_v1,
		.targetsize	= sizeof(struct nf_nat_range),
		.table		= "nat",
		.hooks		= (1 << NF_INET_PRE_ROUTING) |
				  (1 << NF_INET_LOCAL_OUT),
		.me		= THIS_MODULE,
	},
};

static int __init xt_nat_init(void)
{
	return xt_register_targets(xt_nat_target_reg,
				   ARRAY_SIZE(xt_nat_target_reg));
}

static void __exit xt_nat_exit(void)
{
	xt_unregister_targets(xt_nat_target_reg, ARRAY_SIZE(xt_nat_target_reg));
}

module_init(xt_nat_init);
module_exit(xt_nat_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <[email protected]>");
MODULE_ALIAS("ipt_SNAT");
MODULE_ALIAS("ipt_DNAT");
MODULE_ALIAS("ip6t_SNAT");
MODULE_ALIAS("ip6t_DNAT");
Commit	Line	Data
c7232c99 PM	1	/*
	2	* (C) 1999-2001 Paul `Rusty' Russell
	3	* (C) 2002-2006 Netfilter Core Team <[email protected]>
	4	* (C) 2011 Patrick McHardy <[email protected]>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*/
	10
	11	#include <linux/module.h>
	12	#include <linux/skbuff.h>
	13	#include <linux/netfilter.h>
	14	#include <linux/netfilter/x_tables.h>
	15	#include <net/netfilter/nf_nat_core.h>
	16
	17	static int xt_nat_checkentry_v0(const struct xt_tgchk_param *par)
	18	{
	19	const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo;
	20
	21	if (mr->rangesize != 1) {
	22	pr_info("%s: multiple ranges no longer supported\n",
	23	par->target->name);
	24	return -EINVAL;
	25	}
	26	return 0;
	27	}
	28
	29	static void xt_nat_convert_range(struct nf_nat_range *dst,
	30	const struct nf_nat_ipv4_range *src)
	31	{
	32	memset(&dst->min_addr, 0, sizeof(dst->min_addr));
	33	memset(&dst->max_addr, 0, sizeof(dst->max_addr));
	34
	35	dst->flags = src->flags;
	36	dst->min_addr.ip = src->min_ip;
	37	dst->max_addr.ip = src->max_ip;
	38	dst->min_proto = src->min;
	39	dst->max_proto = src->max;
	40	}
	41
	42	static unsigned int
	43	xt_snat_target_v0(struct sk_buff skb, const struct xt_action_param par)
	44	{
	45	const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo;
	46	struct nf_nat_range range;
	47	enum ip_conntrack_info ctinfo;
	48	struct nf_conn *ct;
	49
	50	ct = nf_ct_get(skb, &ctinfo);
	51	NF_CT_ASSERT(ct != NULL &&
	52	(ctinfo == IP_CT_NEW \|\| ctinfo == IP_CT_RELATED \|\|
	53	ctinfo == IP_CT_RELATED_REPLY));
	54
	55	xt_nat_convert_range(&range, &mr->range[0]);
	56	return nf_nat_setup_info(ct, &range, NF_NAT_MANIP_SRC);
	57	}
	58
	59	static unsigned int
	60	xt_dnat_target_v0(struct sk_buff skb, const struct xt_action_param par)
	61	{
	62	const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo;
	63	struct nf_nat_range range;
	64	enum ip_conntrack_info ctinfo;
65	struct nf_conn *ct;
66
67	ct = nf_ct_get(skb, &ctinfo);
68	NF_CT_ASSERT(ct != NULL &&
69	(ctinfo == IP_CT_NEW \|\| ctinfo == IP_CT_RELATED));
70
71	xt_nat_convert_range(&range, &mr->range[0]);
72	return nf_nat_setup_info(ct, &range, NF_NAT_MANIP_DST);
73	}
74
75	static unsigned int
76	xt_snat_target_v1(struct sk_buff skb, const struct xt_action_param par)
77	{
78	const struct nf_nat_range *range = par->targinfo;
79	enum ip_conntrack_info ctinfo;
80	struct nf_conn *ct;
81
82	ct = nf_ct_get(skb, &ctinfo);
83	NF_CT_ASSERT(ct != NULL &&
84	(ctinfo == IP_CT_NEW \|\| ctinfo == IP_CT_RELATED \|\|
85	ctinfo == IP_CT_RELATED_REPLY));
86
87	return nf_nat_setup_info(ct, range, NF_NAT_MANIP_SRC);
88	}
89
90	static unsigned int
91	xt_dnat_target_v1(struct sk_buff skb, const struct xt_action_param par)
92	{
93	const struct nf_nat_range *range = par->targinfo;
94	enum ip_conntrack_info ctinfo;
95	struct nf_conn *ct;
96
97	ct = nf_ct_get(skb, &ctinfo);
98	NF_CT_ASSERT(ct != NULL &&
99	(ctinfo == IP_CT_NEW \|\| ctinfo == IP_CT_RELATED));
100
101	return nf_nat_setup_info(ct, range, NF_NAT_MANIP_DST);
102	}
103
104	static struct xt_target xt_nat_target_reg[] __read_mostly = {
105	{
106	.name = "SNAT",
107	.revision = 0,
108	.checkentry = xt_nat_checkentry_v0,
109	.target = xt_snat_target_v0,
110	.targetsize = sizeof(struct nf_nat_ipv4_multi_range_compat),
111	.family = NFPROTO_IPV4,
112	.table = "nat",
113	.hooks = (1 << NF_INET_POST_ROUTING) \|
939ccba4	114	(1 << NF_INET_LOCAL_IN),
c7232c99 PM	115	.me = THIS_MODULE,
	116	},
	117	{
	118	.name = "DNAT",
	119	.revision = 0,
	120	.checkentry = xt_nat_checkentry_v0,
	121	.target = xt_dnat_target_v0,
	122	.targetsize = sizeof(struct nf_nat_ipv4_multi_range_compat),
	123	.family = NFPROTO_IPV4,
	124	.table = "nat",
	125	.hooks = (1 << NF_INET_PRE_ROUTING) \|
939ccba4	126	(1 << NF_INET_LOCAL_OUT),
c7232c99 PM	127	.me = THIS_MODULE,
	128	},
	129	{
	130	.name = "SNAT",
	131	.revision = 1,
	132	.target = xt_snat_target_v1,
	133	.targetsize = sizeof(struct nf_nat_range),
	134	.table = "nat",
	135	.hooks = (1 << NF_INET_POST_ROUTING) \|
939ccba4	136	(1 << NF_INET_LOCAL_IN),
c7232c99 PM	137	.me = THIS_MODULE,
	138	},
	139	{
	140	.name = "DNAT",
	141	.revision = 1,
	142	.target = xt_dnat_target_v1,
	143	.targetsize = sizeof(struct nf_nat_range),
	144	.table = "nat",
	145	.hooks = (1 << NF_INET_PRE_ROUTING) \|
939ccba4	146	(1 << NF_INET_LOCAL_OUT),
c7232c99 PM	147	.me = THIS_MODULE,
	148	},
	149	};
	150
	151	static int __init xt_nat_init(void)
	152	{
	153	return xt_register_targets(xt_nat_target_reg,
	154	ARRAY_SIZE(xt_nat_target_reg));
	155	}
	156
	157	static void __exit xt_nat_exit(void)
	158	{
	159	xt_unregister_targets(xt_nat_target_reg, ARRAY_SIZE(xt_nat_target_reg));
	160	}
	161
	162	module_init(xt_nat_init);
	163	module_exit(xt_nat_exit);
	164
	165	MODULE_LICENSE("GPL");
58a317f1	166	MODULE_AUTHOR("Patrick McHardy <[email protected]>");
c7232c99 PM	167	MODULE_ALIAS("ipt_SNAT");
c7232c99 PM	168	MODULE_ALIAS("ipt_DNAT");
58a317f1 PM	169	MODULE_ALIAS("ip6t_SNAT");
58a317f1 PM	170	MODULE_ALIAS("ip6t_DNAT");