[mirror_ubuntu-zesty-kernel.git] / net / netfilter / nft_fib.c

/*
 * 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.
 *
 * Generic part shared by ipv4 and ipv6 backends.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables_core.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nft_fib.h>

const struct nla_policy nft_fib_policy[NFTA_FIB_MAX + 1] = {
	[NFTA_FIB_DREG]		= { .type = NLA_U32 },
	[NFTA_FIB_RESULT]	= { .type = NLA_U32 },
	[NFTA_FIB_FLAGS]	= { .type = NLA_U32 },
};
EXPORT_SYMBOL(nft_fib_policy);

#define NFTA_FIB_F_ALL (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR | \
			NFTA_FIB_F_MARK | NFTA_FIB_F_IIF | NFTA_FIB_F_OIF)

int nft_fib_validate(const struct nft_ctx *ctx, const struct nft_expr *expr,
		     const struct nft_data **data)
{
	const struct nft_fib *priv = nft_expr_priv(expr);
	unsigned int hooks;

	switch (priv->result) {
	case NFT_FIB_RESULT_OIF: /* fallthrough */
	case NFT_FIB_RESULT_OIFNAME:
		hooks = (1 << NF_INET_PRE_ROUTING);
		break;
	case NFT_FIB_RESULT_ADDRTYPE:
		if (priv->flags & NFTA_FIB_F_IIF)
			hooks = (1 << NF_INET_PRE_ROUTING) |
				(1 << NF_INET_LOCAL_IN) |
				(1 << NF_INET_FORWARD);
		else if (priv->flags & NFTA_FIB_F_OIF)
			hooks = (1 << NF_INET_LOCAL_OUT) |
				(1 << NF_INET_POST_ROUTING) |
				(1 << NF_INET_FORWARD);
		else
			hooks = (1 << NF_INET_LOCAL_IN) |
				(1 << NF_INET_LOCAL_OUT) |
				(1 << NF_INET_FORWARD) |
				(1 << NF_INET_PRE_ROUTING) |
				(1 << NF_INET_POST_ROUTING);

		break;
	default:
		return -EINVAL;
	}

	return nft_chain_validate_hooks(ctx->chain, hooks);
}
EXPORT_SYMBOL_GPL(nft_fib_validate);

int nft_fib_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
		 const struct nlattr * const tb[])
{
	struct nft_fib *priv = nft_expr_priv(expr);
	unsigned int len;
	int err;

	if (!tb[NFTA_FIB_DREG] || !tb[NFTA_FIB_RESULT] || !tb[NFTA_FIB_FLAGS])
		return -EINVAL;

	priv->flags = ntohl(nla_get_be32(tb[NFTA_FIB_FLAGS]));

	if (priv->flags == 0 || (priv->flags & ~NFTA_FIB_F_ALL))
		return -EINVAL;

	if ((priv->flags & (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR)) ==
			   (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR))
		return -EINVAL;
	if ((priv->flags & (NFTA_FIB_F_IIF | NFTA_FIB_F_OIF)) ==
			   (NFTA_FIB_F_IIF | NFTA_FIB_F_OIF))
		return -EINVAL;
	if ((priv->flags & (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR)) == 0)
		return -EINVAL;

	priv->result = ntohl(nla_get_be32(tb[NFTA_FIB_RESULT]));
	priv->dreg = nft_parse_register(tb[NFTA_FIB_DREG]);

	switch (priv->result) {
	case NFT_FIB_RESULT_OIF:
		if (priv->flags & NFTA_FIB_F_OIF)
			return -EINVAL;
		len = sizeof(int);
		break;
	case NFT_FIB_RESULT_OIFNAME:
		if (priv->flags & NFTA_FIB_F_OIF)
			return -EINVAL;
		len = IFNAMSIZ;
		break;
	case NFT_FIB_RESULT_ADDRTYPE:
		len = sizeof(u32);
		break;
	default:
		return -EINVAL;
	}

	err = nft_validate_register_store(ctx, priv->dreg, NULL,
					  NFT_DATA_VALUE, len);
	if (err < 0)
		return err;

	return nft_fib_validate(ctx, expr, NULL);
}
EXPORT_SYMBOL_GPL(nft_fib_init);

int nft_fib_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
	const struct nft_fib *priv = nft_expr_priv(expr);

	if (nft_dump_register(skb, NFTA_FIB_DREG, priv->dreg))
		return -1;

	if (nla_put_be32(skb, NFTA_FIB_RESULT, htonl(priv->result)))
		return -1;

	if (nla_put_be32(skb, NFTA_FIB_FLAGS, htonl(priv->flags)))
		return -1;

	return 0;
}
EXPORT_SYMBOL_GPL(nft_fib_dump);

void nft_fib_store_result(void *reg, enum nft_fib_result r,
			  const struct nft_pktinfo *pkt, int index)
{
	struct net_device *dev;
	u32 *dreg = reg;

	switch (r) {
	case NFT_FIB_RESULT_OIF:
		*dreg = index;
		break;
	case NFT_FIB_RESULT_OIFNAME:
		dev = dev_get_by_index_rcu(nft_net(pkt), index);
		strncpy(reg, dev ? dev->name : "", IFNAMSIZ);
		break;
	default:
		WARN_ON_ONCE(1);
		*dreg = 0;
		break;
	}
}
EXPORT_SYMBOL_GPL(nft_fib_store_result);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
Commit	Line	Data
f6d0cbcf FW	1	/*
	2	* This program is free software; you can redistribute it and/or modify
	3	* it under the terms of the GNU General Public License version 2 as
	4	* published by the Free Software Foundation.
	5	*
	6	* Generic part shared by ipv4 and ipv6 backends.
	7	*/
	8
	9	#include <linux/kernel.h>
	10	#include <linux/init.h>
	11	#include <linux/module.h>
	12	#include <linux/netlink.h>
	13	#include <linux/netfilter.h>
	14	#include <linux/netfilter/nf_tables.h>
	15	#include <net/netfilter/nf_tables_core.h>
	16	#include <net/netfilter/nf_tables.h>
	17	#include <net/netfilter/nft_fib.h>
	18
	19	const struct nla_policy nft_fib_policy[NFTA_FIB_MAX + 1] = {
	20	[NFTA_FIB_DREG] = { .type = NLA_U32 },
	21	[NFTA_FIB_RESULT] = { .type = NLA_U32 },
	22	[NFTA_FIB_FLAGS] = { .type = NLA_U32 },
	23	};
	24	EXPORT_SYMBOL(nft_fib_policy);
	25
	26	#define NFTA_FIB_F_ALL (NFTA_FIB_F_SADDR \| NFTA_FIB_F_DADDR \| \
	27	NFTA_FIB_F_MARK \| NFTA_FIB_F_IIF \| NFTA_FIB_F_OIF)
	28
	29	int nft_fib_validate(const struct nft_ctx ctx, const struct nft_expr expr,
	30	const struct nft_data **data)
	31	{
	32	const struct nft_fib *priv = nft_expr_priv(expr);
	33	unsigned int hooks;
	34
	35	switch (priv->result) {
	36	case NFT_FIB_RESULT_OIF: /* fallthrough */
	37	case NFT_FIB_RESULT_OIFNAME:
	38	hooks = (1 << NF_INET_PRE_ROUTING);
	39	break;
	40	case NFT_FIB_RESULT_ADDRTYPE:
	41	if (priv->flags & NFTA_FIB_F_IIF)
	42	hooks = (1 << NF_INET_PRE_ROUTING) \|
	43	(1 << NF_INET_LOCAL_IN) \|
	44	(1 << NF_INET_FORWARD);
	45	else if (priv->flags & NFTA_FIB_F_OIF)
	46	hooks = (1 << NF_INET_LOCAL_OUT) \|
	47	(1 << NF_INET_POST_ROUTING) \|
	48	(1 << NF_INET_FORWARD);
	49	else
	50	hooks = (1 << NF_INET_LOCAL_IN) \|
	51	(1 << NF_INET_LOCAL_OUT) \|
	52	(1 << NF_INET_FORWARD) \|
	53	(1 << NF_INET_PRE_ROUTING) \|
	54	(1 << NF_INET_POST_ROUTING);
	55
	56	break;
	57	default:
	58	return -EINVAL;
	59	}
	60
	61	return nft_chain_validate_hooks(ctx->chain, hooks);
	62	}
	63	EXPORT_SYMBOL_GPL(nft_fib_validate);
	64
65	int nft_fib_init(const struct nft_ctx ctx, const struct nft_expr expr,
66	const struct nlattr * const tb[])
67	{
68	struct nft_fib *priv = nft_expr_priv(expr);
69	unsigned int len;
70	int err;
71
72	if (!tb[NFTA_FIB_DREG] \|\| !tb[NFTA_FIB_RESULT] \|\| !tb[NFTA_FIB_FLAGS])
73	return -EINVAL;
74
75	priv->flags = ntohl(nla_get_be32(tb[NFTA_FIB_FLAGS]));
76
77	if (priv->flags == 0 \|\| (priv->flags & ~NFTA_FIB_F_ALL))
78	return -EINVAL;
79
80	if ((priv->flags & (NFTA_FIB_F_SADDR \| NFTA_FIB_F_DADDR)) ==
81	(NFTA_FIB_F_SADDR \| NFTA_FIB_F_DADDR))
82	return -EINVAL;
83	if ((priv->flags & (NFTA_FIB_F_IIF \| NFTA_FIB_F_OIF)) ==
84	(NFTA_FIB_F_IIF \| NFTA_FIB_F_OIF))
85	return -EINVAL;
86	if ((priv->flags & (NFTA_FIB_F_SADDR \| NFTA_FIB_F_DADDR)) == 0)
87	return -EINVAL;
88
11583438	89	priv->result = ntohl(nla_get_be32(tb[NFTA_FIB_RESULT]));
f6d0cbcf FW	90	priv->dreg = nft_parse_register(tb[NFTA_FIB_DREG]);
	91
	92	switch (priv->result) {
	93	case NFT_FIB_RESULT_OIF:
	94	if (priv->flags & NFTA_FIB_F_OIF)
	95	return -EINVAL;
	96	len = sizeof(int);
	97	break;
	98	case NFT_FIB_RESULT_OIFNAME:
	99	if (priv->flags & NFTA_FIB_F_OIF)
	100	return -EINVAL;
	101	len = IFNAMSIZ;
	102	break;
	103	case NFT_FIB_RESULT_ADDRTYPE:
	104	len = sizeof(u32);
	105	break;
	106	default:
	107	return -EINVAL;
	108	}
	109
	110	err = nft_validate_register_store(ctx, priv->dreg, NULL,
	111	NFT_DATA_VALUE, len);
	112	if (err < 0)
	113	return err;
	114
	115	return nft_fib_validate(ctx, expr, NULL);
	116	}
	117	EXPORT_SYMBOL_GPL(nft_fib_init);
	118
	119	int nft_fib_dump(struct sk_buff skb, const struct nft_expr expr)
	120	{
	121	const struct nft_fib *priv = nft_expr_priv(expr);
	122
	123	if (nft_dump_register(skb, NFTA_FIB_DREG, priv->dreg))
	124	return -1;
	125
	126	if (nla_put_be32(skb, NFTA_FIB_RESULT, htonl(priv->result)))
	127	return -1;
	128
	129	if (nla_put_be32(skb, NFTA_FIB_FLAGS, htonl(priv->flags)))
	130	return -1;
	131
	132	return 0;
	133	}
	134	EXPORT_SYMBOL_GPL(nft_fib_dump);
	135
	136	void nft_fib_store_result(void *reg, enum nft_fib_result r,
	137	const struct nft_pktinfo *pkt, int index)
	138	{
	139	struct net_device *dev;
	140	u32 *dreg = reg;
	141
	142	switch (r) {
	143	case NFT_FIB_RESULT_OIF:
	144	*dreg = index;
	145	break;
	146	case NFT_FIB_RESULT_OIFNAME:
0e5a1c7e	147	dev = dev_get_by_index_rcu(nft_net(pkt), index);
f6d0cbcf FW	148	strncpy(reg, dev ? dev->name : "", IFNAMSIZ);
	149	break;
	150	default:
	151	WARN_ON_ONCE(1);
	152	*dreg = 0;
	153	break;
	154	}
	155	}
	156	EXPORT_SYMBOL_GPL(nft_fib_store_result);
	157
	158	MODULE_LICENSE("GPL");
	159	MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");