[mirror_ubuntu-artful-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 | \
			NFTA_FIB_F_PRESENT)

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 0;
}
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, const struct nft_fib *priv,
			  const struct nft_pktinfo *pkt, int index)
{
	struct net_device *dev;
	u32 *dreg = reg;

	switch (priv->result) {
	case NFT_FIB_RESULT_OIF:
		*dreg = (priv->flags & NFTA_FIB_F_PRESENT) ? !!index : index;
		break;
	case NFT_FIB_RESULT_OIFNAME:
		dev = dev_get_by_index_rcu(nft_net(pkt), index);
		if (priv->flags & NFTA_FIB_F_PRESENT)
			*dreg = !!dev;
		else
			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 \| \
055c4b34 PS	27	NFTA_FIB_F_MARK \| NFTA_FIB_F_IIF \| NFTA_FIB_F_OIF \| \
055c4b34 PS	28	NFTA_FIB_F_PRESENT)
f6d0cbcf FW	29
	30	int nft_fib_validate(const struct nft_ctx ctx, const struct nft_expr expr,
	31	const struct nft_data **data)
	32	{
	33	const struct nft_fib *priv = nft_expr_priv(expr);
	34	unsigned int hooks;
	35
	36	switch (priv->result) {
	37	case NFT_FIB_RESULT_OIF: /* fallthrough */
	38	case NFT_FIB_RESULT_OIFNAME:
	39	hooks = (1 << NF_INET_PRE_ROUTING);
	40	break;
	41	case NFT_FIB_RESULT_ADDRTYPE:
	42	if (priv->flags & NFTA_FIB_F_IIF)
	43	hooks = (1 << NF_INET_PRE_ROUTING) \|
	44	(1 << NF_INET_LOCAL_IN) \|
	45	(1 << NF_INET_FORWARD);
	46	else if (priv->flags & NFTA_FIB_F_OIF)
	47	hooks = (1 << NF_INET_LOCAL_OUT) \|
	48	(1 << NF_INET_POST_ROUTING) \|
	49	(1 << NF_INET_FORWARD);
	50	else
	51	hooks = (1 << NF_INET_LOCAL_IN) \|
	52	(1 << NF_INET_LOCAL_OUT) \|
	53	(1 << NF_INET_FORWARD) \|
	54	(1 << NF_INET_PRE_ROUTING) \|
	55	(1 << NF_INET_POST_ROUTING);
	56
	57	break;
	58	default:
	59	return -EINVAL;
	60	}
	61
	62	return nft_chain_validate_hooks(ctx->chain, hooks);
	63	}
	64	EXPORT_SYMBOL_GPL(nft_fib_validate);
	65
	66	int nft_fib_init(const struct nft_ctx ctx, const struct nft_expr expr,
	67	const struct nlattr * const tb[])
	68	{
	69	struct nft_fib *priv = nft_expr_priv(expr);
	70	unsigned int len;
	71	int err;
	72
	73	if (!tb[NFTA_FIB_DREG] \|\| !tb[NFTA_FIB_RESULT] \|\| !tb[NFTA_FIB_FLAGS])
	74	return -EINVAL;
	75
	76	priv->flags = ntohl(nla_get_be32(tb[NFTA_FIB_FLAGS]));
	77
	78	if (priv->flags == 0 \|\| (priv->flags & ~NFTA_FIB_F_ALL))
	79	return -EINVAL;
	80
	81	if ((priv->flags & (NFTA_FIB_F_SADDR \| NFTA_FIB_F_DADDR)) ==
	82	(NFTA_FIB_F_SADDR \| NFTA_FIB_F_DADDR))
	83	return -EINVAL;
	84	if ((priv->flags & (NFTA_FIB_F_IIF \| NFTA_FIB_F_OIF)) ==
	85	(NFTA_FIB_F_IIF \| NFTA_FIB_F_OIF))
	86	return -EINVAL;
	87	if ((priv->flags & (NFTA_FIB_F_SADDR \| NFTA_FIB_F_DADDR)) == 0)
	88	return -EINVAL;
	89
11583438	90	priv->result = ntohl(nla_get_be32(tb[NFTA_FIB_RESULT]));
f6d0cbcf FW	91	priv->dreg = nft_parse_register(tb[NFTA_FIB_DREG]);
	92
	93	switch (priv->result) {
	94	case NFT_FIB_RESULT_OIF:
	95	if (priv->flags & NFTA_FIB_F_OIF)
	96	return -EINVAL;
	97	len = sizeof(int);
	98	break;
	99	case NFT_FIB_RESULT_OIFNAME:
	100	if (priv->flags & NFTA_FIB_F_OIF)
	101	return -EINVAL;
	102	len = IFNAMSIZ;
	103	break;
	104	case NFT_FIB_RESULT_ADDRTYPE:
	105	len = sizeof(u32);
	106	break;
	107	default:
	108	return -EINVAL;
	109	}
	110
	111	err = nft_validate_register_store(ctx, priv->dreg, NULL,
	112	NFT_DATA_VALUE, len);
	113	if (err < 0)
	114	return err;
	115
c56e3956	116	return 0;
f6d0cbcf FW	117	}
	118	EXPORT_SYMBOL_GPL(nft_fib_init);
	119
	120	int nft_fib_dump(struct sk_buff skb, const struct nft_expr expr)
	121	{
	122	const struct nft_fib *priv = nft_expr_priv(expr);
	123
	124	if (nft_dump_register(skb, NFTA_FIB_DREG, priv->dreg))
	125	return -1;
	126
	127	if (nla_put_be32(skb, NFTA_FIB_RESULT, htonl(priv->result)))
	128	return -1;
	129
	130	if (nla_put_be32(skb, NFTA_FIB_FLAGS, htonl(priv->flags)))
	131	return -1;
	132
	133	return 0;
	134	}
	135	EXPORT_SYMBOL_GPL(nft_fib_dump);
	136
055c4b34	137	void nft_fib_store_result(void reg, const struct nft_fib priv,
f6d0cbcf FW	138	const struct nft_pktinfo *pkt, int index)
	139	{
	140	struct net_device *dev;
	141	u32 *dreg = reg;
	142
055c4b34	143	switch (priv->result) {
f6d0cbcf	144	case NFT_FIB_RESULT_OIF:
055c4b34	145	*dreg = (priv->flags & NFTA_FIB_F_PRESENT) ? !!index : index;
f6d0cbcf FW	146	break;
f6d0cbcf FW	147	case NFT_FIB_RESULT_OIFNAME:
0e5a1c7e	148	dev = dev_get_by_index_rcu(nft_net(pkt), index);
055c4b34 PS	149	if (priv->flags & NFTA_FIB_F_PRESENT)
	150	*dreg = !!dev;
	151	else
	152	strncpy(reg, dev ? dev->name : "", IFNAMSIZ);
f6d0cbcf FW	153	break;
	154	default:
	155	WARN_ON_ONCE(1);
	156	*dreg = 0;
	157	break;
	158	}
	159	}
	160	EXPORT_SYMBOL_GPL(nft_fib_store_result);
	161
	162	MODULE_LICENSE("GPL");
	163	MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");