[linux-block.git] / net / netfilter / nft_nat.c

/*
 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
 * Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org>
 * Copyright (c) 2012 Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <linux/string.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_nat.h>
#include <net/netfilter/nf_tables.h>
#include <net/ip.h>

struct nft_nat {
	enum nft_registers      sreg_addr_min:8;
	enum nft_registers      sreg_addr_max:8;
	enum nft_registers      sreg_proto_min:8;
	enum nft_registers      sreg_proto_max:8;
	enum nf_nat_manip_type  type:8;
	u8			family;
	u16			flags;
};

static void nft_nat_eval(const struct nft_expr *expr,
			 struct nft_regs *regs,
			 const struct nft_pktinfo *pkt)
{
	const struct nft_nat *priv = nft_expr_priv(expr);
	enum ip_conntrack_info ctinfo;
	struct nf_conn *ct = nf_ct_get(pkt->skb, &ctinfo);
	struct nf_nat_range2 range;

	memset(&range, 0, sizeof(range));
	if (priv->sreg_addr_min) {
		if (priv->family == AF_INET) {
			range.min_addr.ip = (__force __be32)
					regs->data[priv->sreg_addr_min];
			range.max_addr.ip = (__force __be32)
					regs->data[priv->sreg_addr_max];

		} else {
			memcpy(range.min_addr.ip6,
			       &regs->data[priv->sreg_addr_min],
			       sizeof(range.min_addr.ip6));
			memcpy(range.max_addr.ip6,
			       &regs->data[priv->sreg_addr_max],
			       sizeof(range.max_addr.ip6));
		}
		range.flags |= NF_NAT_RANGE_MAP_IPS;
	}

	if (priv->sreg_proto_min) {
		range.min_proto.all = (__force __be16)nft_reg_load16(
			&regs->data[priv->sreg_proto_min]);
		range.max_proto.all = (__force __be16)nft_reg_load16(
			&regs->data[priv->sreg_proto_max]);
		range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
	}

	range.flags |= priv->flags;

	regs->verdict.code = nf_nat_setup_info(ct, &range, priv->type);
}

static const struct nla_policy nft_nat_policy[NFTA_NAT_MAX + 1] = {
	[NFTA_NAT_TYPE]		 = { .type = NLA_U32 },
	[NFTA_NAT_FAMILY]	 = { .type = NLA_U32 },
	[NFTA_NAT_REG_ADDR_MIN]	 = { .type = NLA_U32 },
	[NFTA_NAT_REG_ADDR_MAX]	 = { .type = NLA_U32 },
	[NFTA_NAT_REG_PROTO_MIN] = { .type = NLA_U32 },
	[NFTA_NAT_REG_PROTO_MAX] = { .type = NLA_U32 },
	[NFTA_NAT_FLAGS]	 = { .type = NLA_U32 },
};

static int nft_nat_validate(const struct nft_ctx *ctx,
			    const struct nft_expr *expr,
			    const struct nft_data **data)
{
	struct nft_nat *priv = nft_expr_priv(expr);
	int err;

	err = nft_chain_validate_dependency(ctx->chain, NFT_CHAIN_T_NAT);
	if (err < 0)
		return err;

	switch (priv->type) {
	case NFT_NAT_SNAT:
		err = nft_chain_validate_hooks(ctx->chain,
					       (1 << NF_INET_POST_ROUTING) |
					       (1 << NF_INET_LOCAL_IN));
		break;
	case NFT_NAT_DNAT:
		err = nft_chain_validate_hooks(ctx->chain,
					       (1 << NF_INET_PRE_ROUTING) |
					       (1 << NF_INET_LOCAL_OUT));
		break;
	}

	return err;
}

static int nft_nat_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
			const struct nlattr * const tb[])
{
	struct nft_nat *priv = nft_expr_priv(expr);
	unsigned int alen, plen;
	u32 family;
	int err;

	if (tb[NFTA_NAT_TYPE] == NULL ||
	    (tb[NFTA_NAT_REG_ADDR_MIN] == NULL &&
	     tb[NFTA_NAT_REG_PROTO_MIN] == NULL))
		return -EINVAL;

	switch (ntohl(nla_get_be32(tb[NFTA_NAT_TYPE]))) {
	case NFT_NAT_SNAT:
		priv->type = NF_NAT_MANIP_SRC;
		break;
	case NFT_NAT_DNAT:
		priv->type = NF_NAT_MANIP_DST;
		break;
	default:
		return -EINVAL;
	}

	if (tb[NFTA_NAT_FAMILY] == NULL)
		return -EINVAL;

	family = ntohl(nla_get_be32(tb[NFTA_NAT_FAMILY]));
	if (family != ctx->family)
		return -EOPNOTSUPP;

	switch (family) {
	case NFPROTO_IPV4:
		alen = FIELD_SIZEOF(struct nf_nat_range, min_addr.ip);
		break;
	case NFPROTO_IPV6:
		alen = FIELD_SIZEOF(struct nf_nat_range, min_addr.ip6);
		break;
	default:
		return -EAFNOSUPPORT;
	}
	priv->family = family;

	if (tb[NFTA_NAT_REG_ADDR_MIN]) {
		priv->sreg_addr_min =
			nft_parse_register(tb[NFTA_NAT_REG_ADDR_MIN]);
		err = nft_validate_register_load(priv->sreg_addr_min, alen);
		if (err < 0)
			return err;

		if (tb[NFTA_NAT_REG_ADDR_MAX]) {
			priv->sreg_addr_max =
				nft_parse_register(tb[NFTA_NAT_REG_ADDR_MAX]);

			err = nft_validate_register_load(priv->sreg_addr_max,
							 alen);
			if (err < 0)
				return err;
		} else {
			priv->sreg_addr_max = priv->sreg_addr_min;
		}
	}

	plen = FIELD_SIZEOF(struct nf_nat_range, min_addr.all);
	if (tb[NFTA_NAT_REG_PROTO_MIN]) {
		priv->sreg_proto_min =
			nft_parse_register(tb[NFTA_NAT_REG_PROTO_MIN]);

		err = nft_validate_register_load(priv->sreg_proto_min, plen);
		if (err < 0)
			return err;

		if (tb[NFTA_NAT_REG_PROTO_MAX]) {
			priv->sreg_proto_max =
				nft_parse_register(tb[NFTA_NAT_REG_PROTO_MAX]);

			err = nft_validate_register_load(priv->sreg_proto_max,
							 plen);
			if (err < 0)
				return err;
		} else {
			priv->sreg_proto_max = priv->sreg_proto_min;
		}
	}

	if (tb[NFTA_NAT_FLAGS]) {
		priv->flags = ntohl(nla_get_be32(tb[NFTA_NAT_FLAGS]));
		if (priv->flags & ~NF_NAT_RANGE_MASK)
			return -EINVAL;
	}

	return nf_ct_netns_get(ctx->net, family);
}

static int nft_nat_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
	const struct nft_nat *priv = nft_expr_priv(expr);

	switch (priv->type) {
	case NF_NAT_MANIP_SRC:
		if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_SNAT)))
			goto nla_put_failure;
		break;
	case NF_NAT_MANIP_DST:
		if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_DNAT)))
			goto nla_put_failure;
		break;
	}

	if (nla_put_be32(skb, NFTA_NAT_FAMILY, htonl(priv->family)))
		goto nla_put_failure;

	if (priv->sreg_addr_min) {
		if (nft_dump_register(skb, NFTA_NAT_REG_ADDR_MIN,
				      priv->sreg_addr_min) ||
		    nft_dump_register(skb, NFTA_NAT_REG_ADDR_MAX,
				      priv->sreg_addr_max))
			goto nla_put_failure;
	}

	if (priv->sreg_proto_min) {
		if (nft_dump_register(skb, NFTA_NAT_REG_PROTO_MIN,
				      priv->sreg_proto_min) ||
		    nft_dump_register(skb, NFTA_NAT_REG_PROTO_MAX,
				      priv->sreg_proto_max))
			goto nla_put_failure;
	}

	if (priv->flags != 0) {
		if (nla_put_be32(skb, NFTA_NAT_FLAGS, htonl(priv->flags)))
			goto nla_put_failure;
	}

	return 0;

nla_put_failure:
	return -1;
}

static void
nft_nat_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
{
	const struct nft_nat *priv = nft_expr_priv(expr);

	nf_ct_netns_put(ctx->net, priv->family);
}

static struct nft_expr_type nft_nat_type;
static const struct nft_expr_ops nft_nat_ops = {
	.type           = &nft_nat_type,
	.size           = NFT_EXPR_SIZE(sizeof(struct nft_nat)),
	.eval           = nft_nat_eval,
	.init           = nft_nat_init,
	.destroy        = nft_nat_destroy,
	.dump           = nft_nat_dump,
	.validate	= nft_nat_validate,
};

static struct nft_expr_type nft_nat_type __read_mostly = {
	.name           = "nat",
	.ops            = &nft_nat_ops,
	.policy         = nft_nat_policy,
	.maxattr        = NFTA_NAT_MAX,
	.owner          = THIS_MODULE,
};

static int __init nft_nat_module_init(void)
{
	return nft_register_expr(&nft_nat_type);
}

static void __exit nft_nat_module_exit(void)
{
	nft_unregister_expr(&nft_nat_type);
}

module_init(nft_nat_module_init);
module_exit(nft_nat_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>");
MODULE_ALIAS_NFT_EXPR("nat");
Commit	Line	Data
eb31628e TB	1	/*
	2	* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
	3	* Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org>
	4	* Copyright (c) 2012 Intel Corporation
	5	*
	6	* This program is free software; you can redistribute it and/or modify it
	7	* under the terms and conditions of the GNU General Public License,
	8	* version 2, as published by the Free Software Foundation.
	9	*
	10	*/
	11
	12	#include <linux/module.h>
	13	#include <linux/init.h>
	14	#include <linux/skbuff.h>
	15	#include <linux/ip.h>
	16	#include <linux/string.h>
	17	#include <linux/netlink.h>
	18	#include <linux/netfilter.h>
	19	#include <linux/netfilter_ipv4.h>
	20	#include <linux/netfilter/nfnetlink.h>
	21	#include <linux/netfilter/nf_tables.h>
	22	#include <net/netfilter/nf_conntrack.h>
	23	#include <net/netfilter/nf_nat.h>
eb31628e	24	#include <net/netfilter/nf_tables.h>
eb31628e TB	25	#include <net/ip.h>
	26
	27	struct nft_nat {
	28	enum nft_registers sreg_addr_min:8;
	29	enum nft_registers sreg_addr_max:8;
	30	enum nft_registers sreg_proto_min:8;
	31	enum nft_registers sreg_proto_max:8;
a4c2e8be PM	32	enum nf_nat_manip_type type:8;
a4c2e8be PM	33	u8 family;
e42eff8a	34	u16 flags;
eb31628e TB	35	};
	36
	37	static void nft_nat_eval(const struct nft_expr *expr,
a55e22e9	38	struct nft_regs *regs,
eb31628e TB	39	const struct nft_pktinfo *pkt)
	40	{
	41	const struct nft_nat *priv = nft_expr_priv(expr);
	42	enum ip_conntrack_info ctinfo;
	43	struct nf_conn *ct = nf_ct_get(pkt->skb, &ctinfo);
2eb0f624	44	struct nf_nat_range2 range;
eb31628e TB	45
	46	memset(&range, 0, sizeof(range));
	47	if (priv->sreg_addr_min) {
	48	if (priv->family == AF_INET) {
98c37b6b	49	range.min_addr.ip = (__force __be32)
49499c3e	50	regs->data[priv->sreg_addr_min];
98c37b6b	51	range.max_addr.ip = (__force __be32)
49499c3e	52	regs->data[priv->sreg_addr_max];
eb31628e TB	53
	54	} else {
	55	memcpy(range.min_addr.ip6,
49499c3e PM	56	&regs->data[priv->sreg_addr_min],
49499c3e PM	57	sizeof(range.min_addr.ip6));
eb31628e	58	memcpy(range.max_addr.ip6,
49499c3e PM	59	&regs->data[priv->sreg_addr_max],
49499c3e PM	60	sizeof(range.max_addr.ip6));
eb31628e TB	61	}
	62	range.flags \|= NF_NAT_RANGE_MAP_IPS;
	63	}
	64
	65	if (priv->sreg_proto_min) {
10596608 LZ	66	range.min_proto.all = (__force __be16)nft_reg_load16(
	67	&regs->data[priv->sreg_proto_min]);
	68	range.max_proto.all = (__force __be16)nft_reg_load16(
	69	&regs->data[priv->sreg_proto_max]);
eb31628e TB	70	range.flags \|= NF_NAT_RANGE_PROTO_SPECIFIED;
	71	}
	72
e42eff8a AB	73	range.flags \|= priv->flags;
e42eff8a AB	74
a55e22e9	75	regs->verdict.code = nf_nat_setup_info(ct, &range, priv->type);
eb31628e TB	76	}
	77
	78	static const struct nla_policy nft_nat_policy[NFTA_NAT_MAX + 1] = {
	79	[NFTA_NAT_TYPE] = { .type = NLA_U32 },
	80	[NFTA_NAT_FAMILY] = { .type = NLA_U32 },
	81	[NFTA_NAT_REG_ADDR_MIN] = { .type = NLA_U32 },
	82	[NFTA_NAT_REG_ADDR_MAX] = { .type = NLA_U32 },
	83	[NFTA_NAT_REG_PROTO_MIN] = { .type = NLA_U32 },
	84	[NFTA_NAT_REG_PROTO_MAX] = { .type = NLA_U32 },
e42eff8a	85	[NFTA_NAT_FLAGS] = { .type = NLA_U32 },
eb31628e TB	86	};
eb31628e TB	87
75e8d06d PNA	88	static int nft_nat_validate(const struct nft_ctx *ctx,
	89	const struct nft_expr *expr,
	90	const struct nft_data **data)
eb31628e TB	91	{
	92	struct nft_nat *priv = nft_expr_priv(expr);
	93	int err;
	94
7210e4e3 PNA	95	err = nft_chain_validate_dependency(ctx->chain, NFT_CHAIN_T_NAT);
	96	if (err < 0)
	97	return err;
	98
75e8d06d PNA	99	switch (priv->type) {
	100	case NFT_NAT_SNAT:
	101	err = nft_chain_validate_hooks(ctx->chain,
	102	(1 << NF_INET_POST_ROUTING) \|
	103	(1 << NF_INET_LOCAL_IN));
	104	break;
	105	case NFT_NAT_DNAT:
	106	err = nft_chain_validate_hooks(ctx->chain,
	107	(1 << NF_INET_PRE_ROUTING) \|
	108	(1 << NF_INET_LOCAL_OUT));
	109	break;
	110	}
	111
	112	return err;
	113	}
	114
	115	static int nft_nat_init(const struct nft_ctx ctx, const struct nft_expr expr,
	116	const struct nlattr * const tb[])
	117	{
	118	struct nft_nat *priv = nft_expr_priv(expr);
d07db988	119	unsigned int alen, plen;
75e8d06d PNA	120	u32 family;
	121	int err;
	122
5c819a39 PNA	123	if (tb[NFTA_NAT_TYPE] == NULL \|\|
	124	(tb[NFTA_NAT_REG_ADDR_MIN] == NULL &&
	125	tb[NFTA_NAT_REG_PROTO_MIN] == NULL))
eb31628e TB	126	return -EINVAL;
	127
	128	switch (ntohl(nla_get_be32(tb[NFTA_NAT_TYPE]))) {
	129	case NFT_NAT_SNAT:
	130	priv->type = NF_NAT_MANIP_SRC;
	131	break;
	132	case NFT_NAT_DNAT:
	133	priv->type = NF_NAT_MANIP_DST;
	134	break;
	135	default:
	136	return -EINVAL;
	137	}
	138
	139	if (tb[NFTA_NAT_FAMILY] == NULL)
	140	return -EINVAL;
	141
a4c2e8be	142	family = ntohl(nla_get_be32(tb[NFTA_NAT_FAMILY]));
36596dad	143	if (family != ctx->family)
a4c2e8be	144	return -EOPNOTSUPP;
d07db988 PM	145
	146	switch (family) {
	147	case NFPROTO_IPV4:
	148	alen = FIELD_SIZEOF(struct nf_nat_range, min_addr.ip);
	149	break;
	150	case NFPROTO_IPV6:
	151	alen = FIELD_SIZEOF(struct nf_nat_range, min_addr.ip6);
	152	break;
	153	default:
	154	return -EAFNOSUPPORT;
	155	}
a4c2e8be	156	priv->family = family;
eb31628e TB	157
eb31628e TB	158	if (tb[NFTA_NAT_REG_ADDR_MIN]) {
61cfac6b	159	priv->sreg_addr_min =
b1c96ed3	160	nft_parse_register(tb[NFTA_NAT_REG_ADDR_MIN]);
d07db988	161	err = nft_validate_register_load(priv->sreg_addr_min, alen);
eb31628e TB	162	if (err < 0)
eb31628e TB	163	return err;
eb31628e	164
61cfac6b PNA	165	if (tb[NFTA_NAT_REG_ADDR_MAX]) {
61cfac6b PNA	166	priv->sreg_addr_max =
b1c96ed3	167	nft_parse_register(tb[NFTA_NAT_REG_ADDR_MAX]);
61cfac6b	168
d07db988 PM	169	err = nft_validate_register_load(priv->sreg_addr_max,
d07db988 PM	170	alen);
61cfac6b PNA	171	if (err < 0)
	172	return err;
	173	} else {
	174	priv->sreg_addr_max = priv->sreg_addr_min;
	175	}
	176	}
eb31628e	177
d07db988	178	plen = FIELD_SIZEOF(struct nf_nat_range, min_addr.all);
eb31628e	179	if (tb[NFTA_NAT_REG_PROTO_MIN]) {
61cfac6b	180	priv->sreg_proto_min =
b1c96ed3	181	nft_parse_register(tb[NFTA_NAT_REG_PROTO_MIN]);
61cfac6b	182
d07db988	183	err = nft_validate_register_load(priv->sreg_proto_min, plen);
eb31628e TB	184	if (err < 0)
eb31628e TB	185	return err;
eb31628e	186
61cfac6b PNA	187	if (tb[NFTA_NAT_REG_PROTO_MAX]) {
61cfac6b PNA	188	priv->sreg_proto_max =
b1c96ed3	189	nft_parse_register(tb[NFTA_NAT_REG_PROTO_MAX]);
61cfac6b	190
d07db988 PM	191	err = nft_validate_register_load(priv->sreg_proto_max,
d07db988 PM	192	plen);
61cfac6b PNA	193	if (err < 0)
	194	return err;
	195	} else {
	196	priv->sreg_proto_max = priv->sreg_proto_min;
	197	}
	198	}
eb31628e	199
e42eff8a AB	200	if (tb[NFTA_NAT_FLAGS]) {
	201	priv->flags = ntohl(nla_get_be32(tb[NFTA_NAT_FLAGS]));
	202	if (priv->flags & ~NF_NAT_RANGE_MASK)
	203	return -EINVAL;
	204	}
	205
20afd423	206	return nf_ct_netns_get(ctx->net, family);
eb31628e TB	207	}
	208
	209	static int nft_nat_dump(struct sk_buff skb, const struct nft_expr expr)
	210	{
	211	const struct nft_nat *priv = nft_expr_priv(expr);
	212
	213	switch (priv->type) {
	214	case NF_NAT_MANIP_SRC:
	215	if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_SNAT)))
	216	goto nla_put_failure;
	217	break;
	218	case NF_NAT_MANIP_DST:
	219	if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_DNAT)))
	220	goto nla_put_failure;
	221	break;
	222	}
	223
	224	if (nla_put_be32(skb, NFTA_NAT_FAMILY, htonl(priv->family)))
	225	goto nla_put_failure;
1e2d56a5 PNA	226
1e2d56a5 PNA	227	if (priv->sreg_addr_min) {
b1c96ed3 PM	228	if (nft_dump_register(skb, NFTA_NAT_REG_ADDR_MIN,
	229	priv->sreg_addr_min) \|\|
	230	nft_dump_register(skb, NFTA_NAT_REG_ADDR_MAX,
	231	priv->sreg_addr_max))
1e2d56a5 PNA	232	goto nla_put_failure;
	233	}
	234
91513606	235	if (priv->sreg_proto_min) {
b1c96ed3 PM	236	if (nft_dump_register(skb, NFTA_NAT_REG_PROTO_MIN,
	237	priv->sreg_proto_min) \|\|
	238	nft_dump_register(skb, NFTA_NAT_REG_PROTO_MAX,
	239	priv->sreg_proto_max))
91513606 PNA	240	goto nla_put_failure;
91513606 PNA	241	}
e42eff8a AB	242
	243	if (priv->flags != 0) {
	244	if (nla_put_be32(skb, NFTA_NAT_FLAGS, htonl(priv->flags)))
	245	goto nla_put_failure;
	246	}
	247
eb31628e TB	248	return 0;
	249
	250	nla_put_failure:
	251	return -1;
	252	}
	253
20afd423 FW	254	static void
	255	nft_nat_destroy(const struct nft_ctx ctx, const struct nft_expr expr)
	256	{
	257	const struct nft_nat *priv = nft_expr_priv(expr);
	258
	259	nf_ct_netns_put(ctx->net, priv->family);
	260	}
	261
eb31628e TB	262	static struct nft_expr_type nft_nat_type;
	263	static const struct nft_expr_ops nft_nat_ops = {
	264	.type = &nft_nat_type,
	265	.size = NFT_EXPR_SIZE(sizeof(struct nft_nat)),
	266	.eval = nft_nat_eval,
	267	.init = nft_nat_init,
20afd423	268	.destroy = nft_nat_destroy,
eb31628e	269	.dump = nft_nat_dump,
7210e4e3	270	.validate = nft_nat_validate,
eb31628e TB	271	};
	272
	273	static struct nft_expr_type nft_nat_type __read_mostly = {
	274	.name = "nat",
	275	.ops = &nft_nat_ops,
	276	.policy = nft_nat_policy,
	277	.maxattr = NFTA_NAT_MAX,
	278	.owner = THIS_MODULE,
	279	};
	280
	281	static int __init nft_nat_module_init(void)
	282	{
a4c2e8be	283	return nft_register_expr(&nft_nat_type);
eb31628e TB	284	}
	285
	286	static void __exit nft_nat_module_exit(void)
	287	{
	288	nft_unregister_expr(&nft_nat_type);
	289	}
	290
	291	module_init(nft_nat_module_init);
	292	module_exit(nft_nat_module_exit);
	293
	294	MODULE_LICENSE("GPL");
	295	MODULE_AUTHOR("Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>");
	296	MODULE_ALIAS_NFT_EXPR("nat");