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

// SPDX-License-Identifier: GPL-2.0-only
/*
 *
 * 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 net_device *dev)
{
	u32 *dreg = reg;
	int index;

	switch (priv->result) {
	case NFT_FIB_RESULT_OIF:
		index = dev ? dev->ifindex : 0;
		*dreg = (priv->flags & NFTA_FIB_F_PRESENT) ? !!index : index;
		break;
	case NFT_FIB_RESULT_OIFNAME:
		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
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
f6d0cbcf	2	/*
f6d0cbcf FW	3	*
	4	* Generic part shared by ipv4 and ipv6 backends.
	5	*/
	6
	7	#include <linux/kernel.h>
	8	#include <linux/init.h>
	9	#include <linux/module.h>
	10	#include <linux/netlink.h>
	11	#include <linux/netfilter.h>
	12	#include <linux/netfilter/nf_tables.h>
	13	#include <net/netfilter/nf_tables_core.h>
	14	#include <net/netfilter/nf_tables.h>
	15	#include <net/netfilter/nft_fib.h>
	16
	17	const struct nla_policy nft_fib_policy[NFTA_FIB_MAX + 1] = {
	18	[NFTA_FIB_DREG] = { .type = NLA_U32 },
	19	[NFTA_FIB_RESULT] = { .type = NLA_U32 },
	20	[NFTA_FIB_FLAGS] = { .type = NLA_U32 },
	21	};
	22	EXPORT_SYMBOL(nft_fib_policy);
	23
	24	#define NFTA_FIB_F_ALL (NFTA_FIB_F_SADDR \| NFTA_FIB_F_DADDR \| \
055c4b34 PS	25	NFTA_FIB_F_MARK \| NFTA_FIB_F_IIF \| NFTA_FIB_F_OIF \| \
055c4b34 PS	26	NFTA_FIB_F_PRESENT)
f6d0cbcf FW	27
	28	int nft_fib_validate(const struct nft_ctx ctx, const struct nft_expr expr,
	29	const struct nft_data **data)
	30	{
	31	const struct nft_fib *priv = nft_expr_priv(expr);
	32	unsigned int hooks;
	33
	34	switch (priv->result) {
	35	case NFT_FIB_RESULT_OIF: /* fallthrough */
	36	case NFT_FIB_RESULT_OIFNAME:
	37	hooks = (1 << NF_INET_PRE_ROUTING);
	38	break;
	39	case NFT_FIB_RESULT_ADDRTYPE:
	40	if (priv->flags & NFTA_FIB_F_IIF)
	41	hooks = (1 << NF_INET_PRE_ROUTING) \|
	42	(1 << NF_INET_LOCAL_IN) \|
	43	(1 << NF_INET_FORWARD);
	44	else if (priv->flags & NFTA_FIB_F_OIF)
	45	hooks = (1 << NF_INET_LOCAL_OUT) \|
	46	(1 << NF_INET_POST_ROUTING) \|
	47	(1 << NF_INET_FORWARD);
	48	else
	49	hooks = (1 << NF_INET_LOCAL_IN) \|
	50	(1 << NF_INET_LOCAL_OUT) \|
	51	(1 << NF_INET_FORWARD) \|
	52	(1 << NF_INET_PRE_ROUTING) \|
	53	(1 << NF_INET_POST_ROUTING);
	54
	55	break;
	56	default:
	57	return -EINVAL;
	58	}
	59
	60	return nft_chain_validate_hooks(ctx->chain, hooks);
	61	}
	62	EXPORT_SYMBOL_GPL(nft_fib_validate);
	63
	64	int nft_fib_init(const struct nft_ctx ctx, const struct nft_expr expr,
	65	const struct nlattr * const tb[])
	66	{
	67	struct nft_fib *priv = nft_expr_priv(expr);
	68	unsigned int len;
	69	int err;
	70
	71	if (!tb[NFTA_FIB_DREG] \|\| !tb[NFTA_FIB_RESULT] \|\| !tb[NFTA_FIB_FLAGS])
	72	return -EINVAL;
	73
	74	priv->flags = ntohl(nla_get_be32(tb[NFTA_FIB_FLAGS]));
	75
	76	if (priv->flags == 0 \|\| (priv->flags & ~NFTA_FIB_F_ALL))
	77	return -EINVAL;
	78
	79	if ((priv->flags & (NFTA_FIB_F_SADDR \| NFTA_FIB_F_DADDR)) ==
	80	(NFTA_FIB_F_SADDR \| NFTA_FIB_F_DADDR))
	81	return -EINVAL;
	82	if ((priv->flags & (NFTA_FIB_F_IIF \| NFTA_FIB_F_OIF)) ==
	83	(NFTA_FIB_F_IIF \| NFTA_FIB_F_OIF))
	84	return -EINVAL;
	85	if ((priv->flags & (NFTA_FIB_F_SADDR \| NFTA_FIB_F_DADDR)) == 0)
	86	return -EINVAL;
	87
11583438	88	priv->result = ntohl(nla_get_be32(tb[NFTA_FIB_RESULT]));
f6d0cbcf FW	89	priv->dreg = nft_parse_register(tb[NFTA_FIB_DREG]);
	90
	91	switch (priv->result) {
	92	case NFT_FIB_RESULT_OIF:
	93	if (priv->flags & NFTA_FIB_F_OIF)
	94	return -EINVAL;
	95	len = sizeof(int);
	96	break;
	97	case NFT_FIB_RESULT_OIFNAME:
	98	if (priv->flags & NFTA_FIB_F_OIF)
	99	return -EINVAL;
	100	len = IFNAMSIZ;
	101	break;
	102	case NFT_FIB_RESULT_ADDRTYPE:
	103	len = sizeof(u32);
	104	break;
	105	default:
	106	return -EINVAL;
	107	}
	108
	109	err = nft_validate_register_store(ctx, priv->dreg, NULL,
	110	NFT_DATA_VALUE, len);
	111	if (err < 0)
	112	return err;
	113
c56e3956	114	return 0;
f6d0cbcf FW	115	}
	116	EXPORT_SYMBOL_GPL(nft_fib_init);
	117
	118	int nft_fib_dump(struct sk_buff skb, const struct nft_expr expr)
	119	{
	120	const struct nft_fib *priv = nft_expr_priv(expr);
	121
	122	if (nft_dump_register(skb, NFTA_FIB_DREG, priv->dreg))
	123	return -1;
	124
	125	if (nla_put_be32(skb, NFTA_FIB_RESULT, htonl(priv->result)))
	126	return -1;
	127
	128	if (nla_put_be32(skb, NFTA_FIB_FLAGS, htonl(priv->flags)))
	129	return -1;
	130
	131	return 0;
	132	}
	133	EXPORT_SYMBOL_GPL(nft_fib_dump);
	134
055c4b34	135	void nft_fib_store_result(void reg, const struct nft_fib priv,
e633508a	136	const struct net_device *dev)
f6d0cbcf	137	{
f6d0cbcf	138	u32 *dreg = reg;
e633508a	139	int index;
f6d0cbcf	140
055c4b34	141	switch (priv->result) {
f6d0cbcf	142	case NFT_FIB_RESULT_OIF:
e633508a	143	index = dev ? dev->ifindex : 0;
055c4b34	144	*dreg = (priv->flags & NFTA_FIB_F_PRESENT) ? !!index : index;
f6d0cbcf FW	145	break;
f6d0cbcf FW	146	case NFT_FIB_RESULT_OIFNAME:
055c4b34 PS	147	if (priv->flags & NFTA_FIB_F_PRESENT)
	148	*dreg = !!dev;
	149	else
	150	strncpy(reg, dev ? dev->name : "", IFNAMSIZ);
f6d0cbcf FW	151	break;
	152	default:
	153	WARN_ON_ONCE(1);
	154	*dreg = 0;
	155	break;
	156	}
	157	}
	158	EXPORT_SYMBOL_GPL(nft_fib_store_result);
	159
	160	MODULE_LICENSE("GPL");
	161	MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");