[mirror_ubuntu-bionic-kernel.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);
	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:
		if (d1 < 0 || d2 > 0)
			regs->verdict.code = NFT_BREAK;
		break;
	case NFT_RANGE_NEQ:
		if (d1 >= 0 && d2 <= 0)
			regs->verdict.code = NFT_BREAK;
		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;

	if (!tb[NFTA_RANGE_SREG]      ||
	    !tb[NFTA_RANGE_OP]	      ||
	    !tb[NFTA_RANGE_FROM_DATA] ||
	    !tb[NFTA_RANGE_TO_DATA])
		return -EINVAL;

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

	if (desc_from.type != NFT_DATA_VALUE) {
		err = -EINVAL;
		goto err1;
	}

	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_to.type != NFT_DATA_VALUE) {
		err = -EINVAL;
		goto err2;
	}

	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_release(&priv->data_to, desc_to.type);
err1:
	nft_data_release(&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 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,
};

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,
};
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);
0f3cd9b3 PNA	31	int d1, d2;
	32
	33	d1 = memcmp(&regs->data[priv->sreg], &priv->data_from, priv->len);
	34	d2 = memcmp(&regs->data[priv->sreg], &priv->data_to, priv->len);
	35	switch (priv->op) {
	36	case NFT_RANGE_EQ:
d2e4d593 AB	37	if (d1 < 0 \|\| d2 > 0)
d2e4d593 AB	38	regs->verdict.code = NFT_BREAK;
0f3cd9b3 PNA	39	break;
0f3cd9b3 PNA	40	case NFT_RANGE_NEQ:
d2e4d593 AB	41	if (d1 >= 0 && d2 <= 0)
d2e4d593 AB	42	regs->verdict.code = NFT_BREAK;
0f3cd9b3 PNA	43	break;
0f3cd9b3 PNA	44	}
0f3cd9b3 PNA	45	}
	46
	47	static const struct nla_policy nft_range_policy[NFTA_RANGE_MAX + 1] = {
	48	[NFTA_RANGE_SREG] = { .type = NLA_U32 },
	49	[NFTA_RANGE_OP] = { .type = NLA_U32 },
	50	[NFTA_RANGE_FROM_DATA] = { .type = NLA_NESTED },
	51	[NFTA_RANGE_TO_DATA] = { .type = NLA_NESTED },
	52	};
	53
	54	static int nft_range_init(const struct nft_ctx ctx, const struct nft_expr expr,
	55	const struct nlattr * const tb[])
	56	{
	57	struct nft_range_expr *priv = nft_expr_priv(expr);
	58	struct nft_data_desc desc_from, desc_to;
	59	int err;
ccca6607	60	u32 op;
0f3cd9b3	61
49cdc4c7 LZ	62	if (!tb[NFTA_RANGE_SREG] \|\|
	63	!tb[NFTA_RANGE_OP] \|\|
	64	!tb[NFTA_RANGE_FROM_DATA] \|\|
	65	!tb[NFTA_RANGE_TO_DATA])
	66	return -EINVAL;
	67
0f3cd9b3 PNA	68	err = nft_data_init(NULL, &priv->data_from, sizeof(priv->data_from),
	69	&desc_from, tb[NFTA_RANGE_FROM_DATA]);
	70	if (err < 0)
	71	return err;
	72
1ab74bda PNA	73	if (desc_from.type != NFT_DATA_VALUE) {
	74	err = -EINVAL;
	75	goto err1;
	76	}
	77
0f3cd9b3 PNA	78	err = nft_data_init(NULL, &priv->data_to, sizeof(priv->data_to),
	79	&desc_to, tb[NFTA_RANGE_TO_DATA]);
	80	if (err < 0)
	81	goto err1;
	82
1ab74bda PNA	83	if (desc_to.type != NFT_DATA_VALUE) {
	84	err = -EINVAL;
	85	goto err2;
	86	}
	87
0f3cd9b3 PNA	88	if (desc_from.len != desc_to.len) {
	89	err = -EINVAL;
	90	goto err2;
	91	}
	92
	93	priv->sreg = nft_parse_register(tb[NFTA_RANGE_SREG]);
	94	err = nft_validate_register_load(priv->sreg, desc_from.len);
	95	if (err < 0)
	96	goto err2;
	97
ccca6607 PNA	98	err = nft_parse_u32_check(tb[NFTA_RANGE_OP], U8_MAX, &op);
	99	if (err < 0)
	100	goto err2;
	101
	102	switch (op) {
	103	case NFT_RANGE_EQ:
	104	case NFT_RANGE_NEQ:
	105	break;
	106	default:
	107	err = -EINVAL;
	108	goto err2;
	109	}
	110
	111	priv->op = op;
0f3cd9b3 PNA	112	priv->len = desc_from.len;
	113	return 0;
	114	err2:
59105446	115	nft_data_release(&priv->data_to, desc_to.type);
0f3cd9b3	116	err1:
59105446	117	nft_data_release(&priv->data_from, desc_from.type);
0f3cd9b3 PNA	118	return err;
	119	}
	120
	121	static int nft_range_dump(struct sk_buff skb, const struct nft_expr expr)
	122	{
	123	const struct nft_range_expr *priv = nft_expr_priv(expr);
	124
	125	if (nft_dump_register(skb, NFTA_RANGE_SREG, priv->sreg))
	126	goto nla_put_failure;
	127	if (nla_put_be32(skb, NFTA_RANGE_OP, htonl(priv->op)))
	128	goto nla_put_failure;
	129
	130	if (nft_data_dump(skb, NFTA_RANGE_FROM_DATA, &priv->data_from,
	131	NFT_DATA_VALUE, priv->len) < 0 \|\|
	132	nft_data_dump(skb, NFTA_RANGE_TO_DATA, &priv->data_to,
	133	NFT_DATA_VALUE, priv->len) < 0)
	134	goto nla_put_failure;
	135	return 0;
	136
	137	nla_put_failure:
	138	return -1;
	139	}
	140
0f3cd9b3 PNA	141	static const struct nft_expr_ops nft_range_ops = {
	142	.type = &nft_range_type,
	143	.size = NFT_EXPR_SIZE(sizeof(struct nft_range_expr)),
	144	.eval = nft_range_eval,
	145	.init = nft_range_init,
	146	.dump = nft_range_dump,
	147	};
	148
4e24877e	149	struct nft_expr_type nft_range_type __read_mostly = {
0f3cd9b3 PNA	150	.name = "range",
	151	.ops = &nft_range_ops,
	152	.policy = nft_range_policy,
	153	.maxattr = NFTA_RANGE_MAX,
	154	.owner = THIS_MODULE,
	155	};