[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_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->sreg = ntohl(nla_get_be32(tb[NFTA_BITWISE_SREG]));
	err = nft_validate_input_register(priv->sreg);
	if (err < 0)
		return err;

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

	priv->len = ntohl(nla_get_be32(tb[NFTA_BITWISE_LEN]));

	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
	66	priv->sreg = ntohl(nla_get_be32(tb[NFTA_BITWISE_SREG]));
67	err = nft_validate_input_register(priv->sreg);
68	if (err < 0)
69	return err;
70
71	priv->dreg = ntohl(nla_get_be32(tb[NFTA_BITWISE_DREG]));
72	err = nft_validate_output_register(priv->dreg);
73	if (err < 0)
74	return err;
75	err = nft_validate_data_load(ctx, priv->dreg, NULL, NFT_DATA_VALUE);
76	if (err < 0)
77	return err;
78
79	priv->len = ntohl(nla_get_be32(tb[NFTA_BITWISE_LEN]));
80
81	err = nft_data_init(NULL, &priv->mask, &d1, tb[NFTA_BITWISE_MASK]);
82	if (err < 0)
83	return err;
84	if (d1.len != priv->len)
85	return -EINVAL;
86
87	err = nft_data_init(NULL, &priv->xor, &d2, tb[NFTA_BITWISE_XOR]);
88	if (err < 0)
89	return err;
90	if (d2.len != priv->len)
91	return -EINVAL;
92
93	return 0;
94	}
95
96	static int nft_bitwise_dump(struct sk_buff skb, const struct nft_expr expr)
97	{
98	const struct nft_bitwise *priv = nft_expr_priv(expr);
99
100	if (nla_put_be32(skb, NFTA_BITWISE_SREG, htonl(priv->sreg)))
101	goto nla_put_failure;
102	if (nla_put_be32(skb, NFTA_BITWISE_DREG, htonl(priv->dreg)))
103	goto nla_put_failure;
104	if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(priv->len)))
105	goto nla_put_failure;
106
107	if (nft_data_dump(skb, NFTA_BITWISE_MASK, &priv->mask,
108	NFT_DATA_VALUE, priv->len) < 0)
109	goto nla_put_failure;
110
111	if (nft_data_dump(skb, NFTA_BITWISE_XOR, &priv->xor,
112	NFT_DATA_VALUE, priv->len) < 0)
113	goto nla_put_failure;
114
115	return 0;
116
117	nla_put_failure:
118	return -1;
119	}
120
ef1f7df9 PM	121	static struct nft_expr_type nft_bitwise_type;
	122	static const struct nft_expr_ops nft_bitwise_ops = {
	123	.type = &nft_bitwise_type,
96518518	124	.size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise)),
96518518 PM	125	.eval = nft_bitwise_eval,
	126	.init = nft_bitwise_init,
	127	.dump = nft_bitwise_dump,
ef1f7df9 PM	128	};
	129
	130	static struct nft_expr_type nft_bitwise_type __read_mostly = {
	131	.name = "bitwise",
	132	.ops = &nft_bitwise_ops,
96518518 PM	133	.policy = nft_bitwise_policy,
96518518 PM	134	.maxattr = NFTA_BITWISE_MAX,
ef1f7df9	135	.owner = THIS_MODULE,
96518518 PM	136	};
	137
	138	int __init nft_bitwise_module_init(void)
	139	{
ef1f7df9	140	return nft_register_expr(&nft_bitwise_type);
96518518 PM	141	}
	142
	143	void nft_bitwise_module_exit(void)
	144	{
ef1f7df9	145	nft_unregister_expr(&nft_bitwise_type);
96518518	146	}