[deliverable/linux.git] / net / netfilter / nft_bitwise.c

/*
 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
 *
 * 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.
 *
 * Development of this code funded by Astaro AG (http://www.astaro.com/)
 */

#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_bitwise {
	enum nft_registers	sreg:8;
	enum nft_registers	dreg:8;
	u8			len;
	struct nft_data		mask;
	struct nft_data		xor;
};

static void nft_bitwise_eval(const struct nft_expr *expr,
			     struct nft_data data[NFT_REG_MAX + 1],
			     const struct nft_pktinfo *pkt)
{
	const struct nft_bitwise *priv = nft_expr_priv(expr);
	const struct nft_data *src = &data[priv->sreg];
	struct nft_data *dst = &data[priv->dreg];
	unsigned int i;

	for (i = 0; i < DIV_ROUND_UP(priv->len, 4); i++) {
		dst->data[i] = (src->data[i] & priv->mask.data[i]) ^
			       priv->xor.data[i];
	}
}

static const struct nla_policy nft_bitwise_policy[NFTA_BITWISE_MAX + 1] = {
	[NFTA_BITWISE_SREG]	= { .type = NLA_U32 },
	[NFTA_BITWISE_DREG]	= { .type = NLA_U32 },
	[NFTA_BITWISE_LEN]	= { .type = NLA_U32 },
	[NFTA_BITWISE_MASK]	= { .type = NLA_NESTED },
	[NFTA_BITWISE_XOR]	= { .type = NLA_NESTED },
};

static int nft_bitwise_init(const struct nft_ctx *ctx,
			    const struct nft_expr *expr,
			    const struct nlattr * const tb[])
{
	struct nft_bitwise *priv = nft_expr_priv(expr);
	struct nft_data_desc d1, d2;
	int err;

	if (tb[NFTA_BITWISE_SREG] == NULL ||
	    tb[NFTA_BITWISE_DREG] == NULL ||
	    tb[NFTA_BITWISE_LEN] == NULL ||
	    tb[NFTA_BITWISE_MASK] == NULL ||
	    tb[NFTA_BITWISE_XOR] == NULL)
		return -EINVAL;

	priv->len  = ntohl(nla_get_be32(tb[NFTA_BITWISE_LEN]));
	priv->sreg = ntohl(nla_get_be32(tb[NFTA_BITWISE_SREG]));
	err = nft_validate_register_load(priv->sreg, priv->len);
	if (err < 0)
		return err;

	priv->dreg = ntohl(nla_get_be32(tb[NFTA_BITWISE_DREG]));
	err = nft_validate_register_store(ctx, priv->dreg, NULL,
					  NFT_DATA_VALUE, priv->len);
	if (err < 0)
		return err;

	err = nft_data_init(NULL, &priv->mask, &d1, tb[NFTA_BITWISE_MASK]);
	if (err < 0)
		return err;
	if (d1.len != priv->len)
		return -EINVAL;

	err = nft_data_init(NULL, &priv->xor, &d2, tb[NFTA_BITWISE_XOR]);
	if (err < 0)
		return err;
	if (d2.len != priv->len)
		return -EINVAL;

	return 0;
}

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

	if (nla_put_be32(skb, NFTA_BITWISE_SREG, htonl(priv->sreg)))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_BITWISE_DREG, htonl(priv->dreg)))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(priv->len)))
		goto nla_put_failure;

	if (nft_data_dump(skb, NFTA_BITWISE_MASK, &priv->mask,
			  NFT_DATA_VALUE, priv->len) < 0)
		goto nla_put_failure;

	if (nft_data_dump(skb, NFTA_BITWISE_XOR, &priv->xor,
			  NFT_DATA_VALUE, priv->len) < 0)
		goto nla_put_failure;

	return 0;

nla_put_failure:
	return -1;
}

static struct nft_expr_type nft_bitwise_type;
static const struct nft_expr_ops nft_bitwise_ops = {
	.type		= &nft_bitwise_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_bitwise)),
	.eval		= nft_bitwise_eval,
	.init		= nft_bitwise_init,
	.dump		= nft_bitwise_dump,
};

static struct nft_expr_type nft_bitwise_type __read_mostly = {
	.name		= "bitwise",
	.ops		= &nft_bitwise_ops,
	.policy		= nft_bitwise_policy,
	.maxattr	= NFTA_BITWISE_MAX,
	.owner		= THIS_MODULE,
};

int __init nft_bitwise_module_init(void)
{
	return nft_register_expr(&nft_bitwise_type);
}

void nft_bitwise_module_exit(void)
{
	nft_unregister_expr(&nft_bitwise_type);
}
Commit	Line	Data
96518518	1	/*
ef1f7df9	2	* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
96518518 PM	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	* Development of this code funded by Astaro AG (http://www.astaro.com/)
	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/init.h>
	13	#include <linux/module.h>
	14	#include <linux/netlink.h>
	15	#include <linux/netfilter.h>
	16	#include <linux/netfilter/nf_tables.h>
	17	#include <net/netfilter/nf_tables_core.h>
	18	#include <net/netfilter/nf_tables.h>
	19
	20	struct nft_bitwise {
	21	enum nft_registers sreg:8;
	22	enum nft_registers dreg:8;
	23	u8 len;
	24	struct nft_data mask;
	25	struct nft_data xor;
	26	};
	27
	28	static void nft_bitwise_eval(const struct nft_expr *expr,
	29	struct nft_data data[NFT_REG_MAX + 1],
	30	const struct nft_pktinfo *pkt)
	31	{
	32	const struct nft_bitwise *priv = nft_expr_priv(expr);
	33	const struct nft_data *src = &data[priv->sreg];
	34	struct nft_data *dst = &data[priv->dreg];
	35	unsigned int i;
	36
	37	for (i = 0; i < DIV_ROUND_UP(priv->len, 4); i++) {
	38	dst->data[i] = (src->data[i] & priv->mask.data[i]) ^
	39	priv->xor.data[i];
	40	}
	41	}
	42
	43	static const struct nla_policy nft_bitwise_policy[NFTA_BITWISE_MAX + 1] = {
	44	[NFTA_BITWISE_SREG] = { .type = NLA_U32 },
	45	[NFTA_BITWISE_DREG] = { .type = NLA_U32 },
	46	[NFTA_BITWISE_LEN] = { .type = NLA_U32 },
	47	[NFTA_BITWISE_MASK] = { .type = NLA_NESTED },
	48	[NFTA_BITWISE_XOR] = { .type = NLA_NESTED },
	49	};
	50
	51	static int nft_bitwise_init(const struct nft_ctx *ctx,
	52	const struct nft_expr *expr,
	53	const struct nlattr * const tb[])
	54	{
	55	struct nft_bitwise *priv = nft_expr_priv(expr);
	56	struct nft_data_desc d1, d2;
	57	int err;
	58
	59	if (tb[NFTA_BITWISE_SREG] == NULL \|\|
	60	tb[NFTA_BITWISE_DREG] == NULL \|\|
	61	tb[NFTA_BITWISE_LEN] == NULL \|\|
	62	tb[NFTA_BITWISE_MASK] == NULL \|\|
	63	tb[NFTA_BITWISE_XOR] == NULL)
	64	return -EINVAL;
	65
d07db988	66	priv->len = ntohl(nla_get_be32(tb[NFTA_BITWISE_LEN]));
96518518	67	priv->sreg = ntohl(nla_get_be32(tb[NFTA_BITWISE_SREG]));
d07db988	68	err = nft_validate_register_load(priv->sreg, priv->len);
96518518 PM	69	if (err < 0)
	70	return err;
	71
	72	priv->dreg = ntohl(nla_get_be32(tb[NFTA_BITWISE_DREG]));
1ec10212 PM	73	err = nft_validate_register_store(ctx, priv->dreg, NULL,
1ec10212 PM	74	NFT_DATA_VALUE, priv->len);
96518518 PM	75	if (err < 0)
	76	return err;
	77
96518518 PM	78	err = nft_data_init(NULL, &priv->mask, &d1, tb[NFTA_BITWISE_MASK]);
	79	if (err < 0)
	80	return err;
	81	if (d1.len != priv->len)
	82	return -EINVAL;
	83
	84	err = nft_data_init(NULL, &priv->xor, &d2, tb[NFTA_BITWISE_XOR]);
	85	if (err < 0)
	86	return err;
	87	if (d2.len != priv->len)
	88	return -EINVAL;
	89
	90	return 0;
	91	}
	92
	93	static int nft_bitwise_dump(struct sk_buff skb, const struct nft_expr expr)
	94	{
	95	const struct nft_bitwise *priv = nft_expr_priv(expr);
	96
	97	if (nla_put_be32(skb, NFTA_BITWISE_SREG, htonl(priv->sreg)))
	98	goto nla_put_failure;
	99	if (nla_put_be32(skb, NFTA_BITWISE_DREG, htonl(priv->dreg)))
	100	goto nla_put_failure;
	101	if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(priv->len)))
	102	goto nla_put_failure;
	103
	104	if (nft_data_dump(skb, NFTA_BITWISE_MASK, &priv->mask,
	105	NFT_DATA_VALUE, priv->len) < 0)
	106	goto nla_put_failure;
	107
	108	if (nft_data_dump(skb, NFTA_BITWISE_XOR, &priv->xor,
	109	NFT_DATA_VALUE, priv->len) < 0)
	110	goto nla_put_failure;
	111
	112	return 0;
	113
	114	nla_put_failure:
	115	return -1;
	116	}
	117
ef1f7df9 PM	118	static struct nft_expr_type nft_bitwise_type;
	119	static const struct nft_expr_ops nft_bitwise_ops = {
	120	.type = &nft_bitwise_type,
96518518	121	.size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise)),
96518518 PM	122	.eval = nft_bitwise_eval,
	123	.init = nft_bitwise_init,
	124	.dump = nft_bitwise_dump,
ef1f7df9 PM	125	};
	126
	127	static struct nft_expr_type nft_bitwise_type __read_mostly = {
	128	.name = "bitwise",
	129	.ops = &nft_bitwise_ops,
96518518 PM	130	.policy = nft_bitwise_policy,
96518518 PM	131	.maxattr = NFTA_BITWISE_MAX,
ef1f7df9	132	.owner = THIS_MODULE,
96518518 PM	133	};
	134
	135	int __init nft_bitwise_module_init(void)
	136	{
ef1f7df9	137	return nft_register_expr(&nft_bitwise_type);
96518518 PM	138	}
	139
	140	void nft_bitwise_module_exit(void)
	141	{
ef1f7df9	142	nft_unregister_expr(&nft_bitwise_type);
96518518	143	}