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

/*
 * Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org>
 *
 * 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/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>

struct nft_range_expr {
	struct nft_data		data_from;
	struct nft_data		data_to;
	enum nft_registers	sreg:8;
	u8			len;
	enum nft_range_ops	op:8;
};

static void nft_range_eval(const struct nft_expr *expr,
			 struct nft_regs *regs,
			 const struct nft_pktinfo *pkt)
{
	const struct nft_range_expr *priv = nft_expr_priv(expr);
	bool mismatch;
	int d1, d2;

	d1 = memcmp(&regs->data[priv->sreg], &priv->data_from, priv->len);
	d2 = memcmp(&regs->data[priv->sreg], &priv->data_to, priv->len);
	switch (priv->op) {
	case NFT_RANGE_EQ:
		mismatch = (d1 < 0 || d2 > 0);
		break;
	case NFT_RANGE_NEQ:
		mismatch = (d1 >= 0 && d2 <= 0);
		break;
	}

	if (mismatch)
		regs->verdict.code = NFT_BREAK;
}

static const struct nla_policy nft_range_policy[NFTA_RANGE_MAX + 1] = {
	[NFTA_RANGE_SREG]		= { .type = NLA_U32 },
	[NFTA_RANGE_OP]			= { .type = NLA_U32 },
	[NFTA_RANGE_FROM_DATA]		= { .type = NLA_NESTED },
	[NFTA_RANGE_TO_DATA]		= { .type = NLA_NESTED },
};

static int nft_range_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
			const struct nlattr * const tb[])
{
	struct nft_range_expr *priv = nft_expr_priv(expr);
	struct nft_data_desc desc_from, desc_to;
	int err;
	u32 op;

	err = nft_data_init(NULL, &priv->data_from, sizeof(priv->data_from),
			    &desc_from, tb[NFTA_RANGE_FROM_DATA]);
	if (err < 0)
		return err;

	err = nft_data_init(NULL, &priv->data_to, sizeof(priv->data_to),
			    &desc_to, tb[NFTA_RANGE_TO_DATA]);
	if (err < 0)
		goto err1;

	if (desc_from.len != desc_to.len) {
		err = -EINVAL;
		goto err2;
	}

	priv->sreg = nft_parse_register(tb[NFTA_RANGE_SREG]);
	err = nft_validate_register_load(priv->sreg, desc_from.len);
	if (err < 0)
		goto err2;

	err = nft_parse_u32_check(tb[NFTA_RANGE_OP], U8_MAX, &op);
	if (err < 0)
		goto err2;

	switch (op) {
	case NFT_RANGE_EQ:
	case NFT_RANGE_NEQ:
		break;
	default:
		err = -EINVAL;
		goto err2;
	}

	priv->op  = op;
	priv->len = desc_from.len;
	return 0;
err2:
	nft_data_uninit(&priv->data_to, desc_to.type);
err1:
	nft_data_uninit(&priv->data_from, desc_from.type);
	return err;
}

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

	if (nft_dump_register(skb, NFTA_RANGE_SREG, priv->sreg))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_RANGE_OP, htonl(priv->op)))
		goto nla_put_failure;

	if (nft_data_dump(skb, NFTA_RANGE_FROM_DATA, &priv->data_from,
			  NFT_DATA_VALUE, priv->len) < 0 ||
	    nft_data_dump(skb, NFTA_RANGE_TO_DATA, &priv->data_to,
			  NFT_DATA_VALUE, priv->len) < 0)
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -1;
}

static struct nft_expr_type nft_range_type;
static const struct nft_expr_ops nft_range_ops = {
	.type		= &nft_range_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_range_expr)),
	.eval		= nft_range_eval,
	.init		= nft_range_init,
	.dump		= nft_range_dump,
};

static struct nft_expr_type nft_range_type __read_mostly = {
	.name		= "range",
	.ops		= &nft_range_ops,
	.policy		= nft_range_policy,
	.maxattr	= NFTA_RANGE_MAX,
	.owner		= THIS_MODULE,
};

int __init nft_range_module_init(void)
{
	return nft_register_expr(&nft_range_type);
}

void nft_range_module_exit(void)
{
	nft_unregister_expr(&nft_range_type);
}
Commit	Line	Data
0f3cd9b3 PNA	1	/*
	2	* Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	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
	18	struct nft_range_expr {
	19	struct nft_data data_from;
	20	struct nft_data data_to;
	21	enum nft_registers sreg:8;
	22	u8 len;
	23	enum nft_range_ops op:8;
	24	};
	25
	26	static void nft_range_eval(const struct nft_expr *expr,
	27	struct nft_regs *regs,
	28	const struct nft_pktinfo *pkt)
	29	{
	30	const struct nft_range_expr *priv = nft_expr_priv(expr);
	31	bool mismatch;
	32	int d1, d2;
	33
	34	d1 = memcmp(&regs->data[priv->sreg], &priv->data_from, priv->len);
	35	d2 = memcmp(&regs->data[priv->sreg], &priv->data_to, priv->len);
	36	switch (priv->op) {
	37	case NFT_RANGE_EQ:
	38	mismatch = (d1 < 0 \|\| d2 > 0);
	39	break;
	40	case NFT_RANGE_NEQ:
	41	mismatch = (d1 >= 0 && d2 <= 0);
	42	break;
	43	}
	44
	45	if (mismatch)
	46	regs->verdict.code = NFT_BREAK;
	47	}
	48
	49	static const struct nla_policy nft_range_policy[NFTA_RANGE_MAX + 1] = {
	50	[NFTA_RANGE_SREG] = { .type = NLA_U32 },
	51	[NFTA_RANGE_OP] = { .type = NLA_U32 },
	52	[NFTA_RANGE_FROM_DATA] = { .type = NLA_NESTED },
	53	[NFTA_RANGE_TO_DATA] = { .type = NLA_NESTED },
	54	};
	55
	56	static int nft_range_init(const struct nft_ctx ctx, const struct nft_expr expr,
	57	const struct nlattr * const tb[])
	58	{
	59	struct nft_range_expr *priv = nft_expr_priv(expr);
	60	struct nft_data_desc desc_from, desc_to;
	61	int err;
ccca6607	62	u32 op;
0f3cd9b3 PNA	63
	64	err = nft_data_init(NULL, &priv->data_from, sizeof(priv->data_from),
	65	&desc_from, tb[NFTA_RANGE_FROM_DATA]);
	66	if (err < 0)
	67	return err;
	68
	69	err = nft_data_init(NULL, &priv->data_to, sizeof(priv->data_to),
	70	&desc_to, tb[NFTA_RANGE_TO_DATA]);
	71	if (err < 0)
	72	goto err1;
	73
	74	if (desc_from.len != desc_to.len) {
	75	err = -EINVAL;
	76	goto err2;
	77	}
	78
	79	priv->sreg = nft_parse_register(tb[NFTA_RANGE_SREG]);
	80	err = nft_validate_register_load(priv->sreg, desc_from.len);
	81	if (err < 0)
	82	goto err2;
	83
ccca6607 PNA	84	err = nft_parse_u32_check(tb[NFTA_RANGE_OP], U8_MAX, &op);
	85	if (err < 0)
	86	goto err2;
	87
	88	switch (op) {
	89	case NFT_RANGE_EQ:
	90	case NFT_RANGE_NEQ:
	91	break;
	92	default:
	93	err = -EINVAL;
	94	goto err2;
	95	}
	96
	97	priv->op = op;
0f3cd9b3 PNA	98	priv->len = desc_from.len;
	99	return 0;
	100	err2:
	101	nft_data_uninit(&priv->data_to, desc_to.type);
	102	err1:
	103	nft_data_uninit(&priv->data_from, desc_from.type);
	104	return err;
	105	}
	106
	107	static int nft_range_dump(struct sk_buff skb, const struct nft_expr expr)
	108	{
	109	const struct nft_range_expr *priv = nft_expr_priv(expr);
	110
	111	if (nft_dump_register(skb, NFTA_RANGE_SREG, priv->sreg))
	112	goto nla_put_failure;
	113	if (nla_put_be32(skb, NFTA_RANGE_OP, htonl(priv->op)))
	114	goto nla_put_failure;
	115
	116	if (nft_data_dump(skb, NFTA_RANGE_FROM_DATA, &priv->data_from,
	117	NFT_DATA_VALUE, priv->len) < 0 \|\|
	118	nft_data_dump(skb, NFTA_RANGE_TO_DATA, &priv->data_to,
	119	NFT_DATA_VALUE, priv->len) < 0)
	120	goto nla_put_failure;
	121	return 0;
	122
	123	nla_put_failure:
	124	return -1;
	125	}
	126
	127	static struct nft_expr_type nft_range_type;
	128	static const struct nft_expr_ops nft_range_ops = {
	129	.type = &nft_range_type,
	130	.size = NFT_EXPR_SIZE(sizeof(struct nft_range_expr)),
	131	.eval = nft_range_eval,
	132	.init = nft_range_init,
	133	.dump = nft_range_dump,
	134	};
	135
	136	static struct nft_expr_type nft_range_type __read_mostly = {
	137	.name = "range",
	138	.ops = &nft_range_ops,
	139	.policy = nft_range_policy,
	140	.maxattr = NFTA_RANGE_MAX,
	141	.owner = THIS_MODULE,
	142	};
	143
	144	int __init nft_range_module_init(void)
	145	{
	146	return nft_register_expr(&nft_range_type);
	147	}
	148
	149	void nft_range_module_exit(void)
	150	{
	151	nft_unregister_expr(&nft_range_type);
	152	}