[linux-2.6-block.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_regs *regs,
			     const struct nft_pktinfo *pkt)
{
	const struct nft_bitwise *priv = nft_expr_priv(expr);
	const u32 *src = &regs->data[priv->sreg];
	u32 *dst = &regs->data[priv->dreg];
	unsigned int i;

	for (i = 0; i < DIV_ROUND_UP(priv->len, 4); i++)
		dst[i] = (src[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;
	u32 len;
	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;

	err = nft_parse_u32_check(tb[NFTA_BITWISE_LEN], U8_MAX, &len);
	if (err < 0)
		return err;

	priv->len = len;

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

	priv->dreg = nft_parse_register(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, sizeof(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, sizeof(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 (nft_dump_register(skb, NFTA_BITWISE_SREG, priv->sreg))
		goto nla_put_failure;
	if (nft_dump_register(skb, NFTA_BITWISE_DREG, 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,
a55e22e9	29	struct nft_regs *regs,
96518518 PM	30	const struct nft_pktinfo *pkt)
	31	{
	32	const struct nft_bitwise *priv = nft_expr_priv(expr);
49499c3e PM	33	const u32 *src = &regs->data[priv->sreg];
49499c3e PM	34	u32 *dst = &regs->data[priv->dreg];
96518518 PM	35	unsigned int i;
96518518 PM	36
fad136ea PM	37	for (i = 0; i < DIV_ROUND_UP(priv->len, 4); i++)
fad136ea PM	38	dst[i] = (src[i] & priv->mask.data[i]) ^ priv->xor.data[i];
96518518 PM	39	}
	40
	41	static const struct nla_policy nft_bitwise_policy[NFTA_BITWISE_MAX + 1] = {
	42	[NFTA_BITWISE_SREG] = { .type = NLA_U32 },
	43	[NFTA_BITWISE_DREG] = { .type = NLA_U32 },
	44	[NFTA_BITWISE_LEN] = { .type = NLA_U32 },
	45	[NFTA_BITWISE_MASK] = { .type = NLA_NESTED },
	46	[NFTA_BITWISE_XOR] = { .type = NLA_NESTED },
	47	};
	48
	49	static int nft_bitwise_init(const struct nft_ctx *ctx,
	50	const struct nft_expr *expr,
	51	const struct nlattr * const tb[])
	52	{
	53	struct nft_bitwise *priv = nft_expr_priv(expr);
	54	struct nft_data_desc d1, d2;
36b701fa	55	u32 len;
96518518 PM	56	int err;
	57
	58	if (tb[NFTA_BITWISE_SREG] == NULL \|\|
	59	tb[NFTA_BITWISE_DREG] == NULL \|\|
	60	tb[NFTA_BITWISE_LEN] == NULL \|\|
	61	tb[NFTA_BITWISE_MASK] == NULL \|\|
	62	tb[NFTA_BITWISE_XOR] == NULL)
	63	return -EINVAL;
	64
36b701fa LGL	65	err = nft_parse_u32_check(tb[NFTA_BITWISE_LEN], U8_MAX, &len);
	66	if (err < 0)
	67	return err;
	68
	69	priv->len = len;
	70
b1c96ed3	71	priv->sreg = nft_parse_register(tb[NFTA_BITWISE_SREG]);
d07db988	72	err = nft_validate_register_load(priv->sreg, priv->len);
96518518 PM	73	if (err < 0)
	74	return err;
	75
b1c96ed3	76	priv->dreg = nft_parse_register(tb[NFTA_BITWISE_DREG]);
1ec10212 PM	77	err = nft_validate_register_store(ctx, priv->dreg, NULL,
1ec10212 PM	78	NFT_DATA_VALUE, priv->len);
96518518 PM	79	if (err < 0)
	80	return err;
	81
d0a11fc3 PM	82	err = nft_data_init(NULL, &priv->mask, sizeof(priv->mask), &d1,
d0a11fc3 PM	83	tb[NFTA_BITWISE_MASK]);
96518518 PM	84	if (err < 0)
	85	return err;
	86	if (d1.len != priv->len)
	87	return -EINVAL;
	88
d0a11fc3 PM	89	err = nft_data_init(NULL, &priv->xor, sizeof(priv->xor), &d2,
d0a11fc3 PM	90	tb[NFTA_BITWISE_XOR]);
96518518 PM	91	if (err < 0)
	92	return err;
	93	if (d2.len != priv->len)
	94	return -EINVAL;
	95
	96	return 0;
	97	}
	98
	99	static int nft_bitwise_dump(struct sk_buff skb, const struct nft_expr expr)
	100	{
	101	const struct nft_bitwise *priv = nft_expr_priv(expr);
	102
b1c96ed3	103	if (nft_dump_register(skb, NFTA_BITWISE_SREG, priv->sreg))
96518518	104	goto nla_put_failure;
b1c96ed3	105	if (nft_dump_register(skb, NFTA_BITWISE_DREG, priv->dreg))
96518518 PM	106	goto nla_put_failure;
	107	if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(priv->len)))
	108	goto nla_put_failure;
	109
	110	if (nft_data_dump(skb, NFTA_BITWISE_MASK, &priv->mask,
	111	NFT_DATA_VALUE, priv->len) < 0)
	112	goto nla_put_failure;
	113
	114	if (nft_data_dump(skb, NFTA_BITWISE_XOR, &priv->xor,
	115	NFT_DATA_VALUE, priv->len) < 0)
	116	goto nla_put_failure;
	117
	118	return 0;
	119
	120	nla_put_failure:
	121	return -1;
	122	}
	123
ef1f7df9 PM	124	static struct nft_expr_type nft_bitwise_type;
	125	static const struct nft_expr_ops nft_bitwise_ops = {
	126	.type = &nft_bitwise_type,
96518518	127	.size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise)),
96518518 PM	128	.eval = nft_bitwise_eval,
	129	.init = nft_bitwise_init,
	130	.dump = nft_bitwise_dump,
ef1f7df9 PM	131	};
	132
	133	static struct nft_expr_type nft_bitwise_type __read_mostly = {
	134	.name = "bitwise",
	135	.ops = &nft_bitwise_ops,
96518518 PM	136	.policy = nft_bitwise_policy,
96518518 PM	137	.maxattr = NFTA_BITWISE_MAX,
ef1f7df9	138	.owner = THIS_MODULE,
96518518 PM	139	};
	140
	141	int __init nft_bitwise_module_init(void)
	142	{
ef1f7df9	143	return nft_register_expr(&nft_bitwise_type);
96518518 PM	144	}
	145
	146	void nft_bitwise_module_exit(void)
	147	{
ef1f7df9	148	nft_unregister_expr(&nft_bitwise_type);
96518518	149	}