[linux-2.6-block.git] / net / netfilter / nft_byteorder.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_byteorder {
	enum nft_registers	sreg:8;
	enum nft_registers	dreg:8;
	enum nft_byteorder_ops	op:8;
	u8			len;
	u8			size;
};

static void nft_byteorder_eval(const struct nft_expr *expr,
			       struct nft_regs *regs,
			       const struct nft_pktinfo *pkt)
{
	const struct nft_byteorder *priv = nft_expr_priv(expr);
	u32 *src = &regs->data[priv->sreg];
	u32 *dst = &regs->data[priv->dreg];
	union { u32 u32; u16 u16; } *s, *d;
	unsigned int i;

	s = (void *)src;
	d = (void *)dst;

	switch (priv->size) {
	case 4:
		switch (priv->op) {
		case NFT_BYTEORDER_NTOH:
			for (i = 0; i < priv->len / 4; i++)
				d[i].u32 = ntohl((__force __be32)s[i].u32);
			break;
		case NFT_BYTEORDER_HTON:
			for (i = 0; i < priv->len / 4; i++)
				d[i].u32 = (__force __u32)htonl(s[i].u32);
			break;
		}
		break;
	case 2:
		switch (priv->op) {
		case NFT_BYTEORDER_NTOH:
			for (i = 0; i < priv->len / 2; i++)
				d[i].u16 = ntohs((__force __be16)s[i].u16);
			break;
		case NFT_BYTEORDER_HTON:
			for (i = 0; i < priv->len / 2; i++)
				d[i].u16 = (__force __u16)htons(s[i].u16);
			break;
		}
		break;
	}
}

static const struct nla_policy nft_byteorder_policy[NFTA_BYTEORDER_MAX + 1] = {
	[NFTA_BYTEORDER_SREG]	= { .type = NLA_U32 },
	[NFTA_BYTEORDER_DREG]	= { .type = NLA_U32 },
	[NFTA_BYTEORDER_OP]	= { .type = NLA_U32 },
	[NFTA_BYTEORDER_LEN]	= { .type = NLA_U32 },
	[NFTA_BYTEORDER_SIZE]	= { .type = NLA_U32 },
};

static int nft_byteorder_init(const struct nft_ctx *ctx,
			      const struct nft_expr *expr,
			      const struct nlattr * const tb[])
{
	struct nft_byteorder *priv = nft_expr_priv(expr);
	int err;

	if (tb[NFTA_BYTEORDER_SREG] == NULL ||
	    tb[NFTA_BYTEORDER_DREG] == NULL ||
	    tb[NFTA_BYTEORDER_LEN] == NULL ||
	    tb[NFTA_BYTEORDER_SIZE] == NULL ||
	    tb[NFTA_BYTEORDER_OP] == NULL)
		return -EINVAL;

	priv->op = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_OP]));
	switch (priv->op) {
	case NFT_BYTEORDER_NTOH:
	case NFT_BYTEORDER_HTON:
		break;
	default:
		return -EINVAL;
	}

	priv->size = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_SIZE]));
	switch (priv->size) {
	case 2:
	case 4:
		break;
	default:
		return -EINVAL;
	}

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

	priv->dreg = nft_parse_register(tb[NFTA_BYTEORDER_DREG]);
	return nft_validate_register_store(ctx, priv->dreg, NULL,
					   NFT_DATA_VALUE, priv->len);
}

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

	if (nft_dump_register(skb, NFTA_BYTEORDER_SREG, priv->sreg))
		goto nla_put_failure;
	if (nft_dump_register(skb, NFTA_BYTEORDER_DREG, priv->dreg))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_BYTEORDER_OP, htonl(priv->op)))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_BYTEORDER_LEN, htonl(priv->len)))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_BYTEORDER_SIZE, htonl(priv->size)))
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -1;
}

static struct nft_expr_type nft_byteorder_type;
static const struct nft_expr_ops nft_byteorder_ops = {
	.type		= &nft_byteorder_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_byteorder)),
	.eval		= nft_byteorder_eval,
	.init		= nft_byteorder_init,
	.dump		= nft_byteorder_dump,
};

static struct nft_expr_type nft_byteorder_type __read_mostly = {
	.name		= "byteorder",
	.ops		= &nft_byteorder_ops,
	.policy		= nft_byteorder_policy,
	.maxattr	= NFTA_BYTEORDER_MAX,
	.owner		= THIS_MODULE,
};

int __init nft_byteorder_module_init(void)
{
	return nft_register_expr(&nft_byteorder_type);
}

void nft_byteorder_module_exit(void)
{
	nft_unregister_expr(&nft_byteorder_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_byteorder {
	21	enum nft_registers sreg:8;
	22	enum nft_registers dreg:8;
	23	enum nft_byteorder_ops op:8;
	24	u8 len;
	25	u8 size;
	26	};
	27
	28	static void nft_byteorder_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_byteorder *priv = nft_expr_priv(expr);
49499c3e PM	33	u32 *src = &regs->data[priv->sreg];
49499c3e PM	34	u32 *dst = &regs->data[priv->dreg];
96518518 PM	35	union { u32 u32; u16 u16; } s, d;
	36	unsigned int i;
	37
fad136ea PM	38	s = (void *)src;
fad136ea PM	39	d = (void *)dst;
96518518 PM	40
	41	switch (priv->size) {
	42	case 4:
	43	switch (priv->op) {
	44	case NFT_BYTEORDER_NTOH:
	45	for (i = 0; i < priv->len / 4; i++)
	46	d[i].u32 = ntohl((__force __be32)s[i].u32);
	47	break;
	48	case NFT_BYTEORDER_HTON:
	49	for (i = 0; i < priv->len / 4; i++)
	50	d[i].u32 = (__force __u32)htonl(s[i].u32);
	51	break;
	52	}
	53	break;
	54	case 2:
	55	switch (priv->op) {
	56	case NFT_BYTEORDER_NTOH:
	57	for (i = 0; i < priv->len / 2; i++)
	58	d[i].u16 = ntohs((__force __be16)s[i].u16);
	59	break;
	60	case NFT_BYTEORDER_HTON:
	61	for (i = 0; i < priv->len / 2; i++)
	62	d[i].u16 = (__force __u16)htons(s[i].u16);
	63	break;
	64	}
	65	break;
	66	}
	67	}
	68
	69	static const struct nla_policy nft_byteorder_policy[NFTA_BYTEORDER_MAX + 1] = {
	70	[NFTA_BYTEORDER_SREG] = { .type = NLA_U32 },
	71	[NFTA_BYTEORDER_DREG] = { .type = NLA_U32 },
	72	[NFTA_BYTEORDER_OP] = { .type = NLA_U32 },
	73	[NFTA_BYTEORDER_LEN] = { .type = NLA_U32 },
	74	[NFTA_BYTEORDER_SIZE] = { .type = NLA_U32 },
	75	};
	76
	77	static int nft_byteorder_init(const struct nft_ctx *ctx,
	78	const struct nft_expr *expr,
	79	const struct nlattr * const tb[])
	80	{
	81	struct nft_byteorder *priv = nft_expr_priv(expr);
	82	int err;
	83
	84	if (tb[NFTA_BYTEORDER_SREG] == NULL \|\|
	85	tb[NFTA_BYTEORDER_DREG] == NULL \|\|
	86	tb[NFTA_BYTEORDER_LEN] == NULL \|\|
	87	tb[NFTA_BYTEORDER_SIZE] == NULL \|\|
	88	tb[NFTA_BYTEORDER_OP] == NULL)
	89	return -EINVAL;
	90
96518518 PM	91	priv->op = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_OP]));
	92	switch (priv->op) {
	93	case NFT_BYTEORDER_NTOH:
	94	case NFT_BYTEORDER_HTON:
	95	break;
	96	default:
	97	return -EINVAL;
	98	}
	99
96518518 PM	100	priv->size = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_SIZE]));
	101	switch (priv->size) {
	102	case 2:
	103	case 4:
	104	break;
	105	default:
	106	return -EINVAL;
	107	}
	108
b1c96ed3	109	priv->sreg = nft_parse_register(tb[NFTA_BYTEORDER_SREG]);
d07db988 PM	110	priv->len = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_LEN]));
d07db988 PM	111	err = nft_validate_register_load(priv->sreg, priv->len);
45d9bcda PM	112	if (err < 0)
	113	return err;
	114
b1c96ed3	115	priv->dreg = nft_parse_register(tb[NFTA_BYTEORDER_DREG]);
27e6d201 PM	116	return nft_validate_register_store(ctx, priv->dreg, NULL,
27e6d201 PM	117	NFT_DATA_VALUE, priv->len);
96518518 PM	118	}
	119
	120	static int nft_byteorder_dump(struct sk_buff skb, const struct nft_expr expr)
	121	{
	122	const struct nft_byteorder *priv = nft_expr_priv(expr);
	123
b1c96ed3	124	if (nft_dump_register(skb, NFTA_BYTEORDER_SREG, priv->sreg))
96518518	125	goto nla_put_failure;
b1c96ed3	126	if (nft_dump_register(skb, NFTA_BYTEORDER_DREG, priv->dreg))
96518518 PM	127	goto nla_put_failure;
	128	if (nla_put_be32(skb, NFTA_BYTEORDER_OP, htonl(priv->op)))
	129	goto nla_put_failure;
	130	if (nla_put_be32(skb, NFTA_BYTEORDER_LEN, htonl(priv->len)))
	131	goto nla_put_failure;
	132	if (nla_put_be32(skb, NFTA_BYTEORDER_SIZE, htonl(priv->size)))
	133	goto nla_put_failure;
	134	return 0;
	135
	136	nla_put_failure:
	137	return -1;
	138	}
	139
ef1f7df9 PM	140	static struct nft_expr_type nft_byteorder_type;
	141	static const struct nft_expr_ops nft_byteorder_ops = {
	142	.type = &nft_byteorder_type,
96518518	143	.size = NFT_EXPR_SIZE(sizeof(struct nft_byteorder)),
96518518 PM	144	.eval = nft_byteorder_eval,
	145	.init = nft_byteorder_init,
	146	.dump = nft_byteorder_dump,
ef1f7df9 PM	147	};
	148
	149	static struct nft_expr_type nft_byteorder_type __read_mostly = {
	150	.name = "byteorder",
	151	.ops = &nft_byteorder_ops,
96518518 PM	152	.policy = nft_byteorder_policy,
96518518 PM	153	.maxattr = NFTA_BYTEORDER_MAX,
ef1f7df9	154	.owner = THIS_MODULE,
96518518 PM	155	};
	156
	157	int __init nft_byteorder_module_init(void)
	158	{
ef1f7df9	159	return nft_register_expr(&nft_byteorder_type);
96518518 PM	160	}
	161
	162	void nft_byteorder_module_exit(void)
	163	{
ef1f7df9	164	nft_unregister_expr(&nft_byteorder_type);
96518518	165	}