[deliverable/linux.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_data data[NFT_REG_MAX + 1],
			       const struct nft_pktinfo *pkt)
{
	const struct nft_byteorder *priv = nft_expr_priv(expr);
	struct nft_data *src = &data[priv->sreg], *dst = &data[priv->dreg];
	union { u32 u32; u16 u16; } *s, *d;
	unsigned int i;

	s = (void *)src->data;
	d = (void *)dst->data;

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

	priv->dreg = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_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->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->len = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_LEN]));
	if (priv->len == 0 || priv->len > FIELD_SIZEOF(struct nft_data, data))
		return -EINVAL;

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

	return 0;
}

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

	if (nla_put_be32(skb, NFTA_BYTEORDER_SREG, htonl(priv->sreg)))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_BYTEORDER_DREG, htonl(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,
	29	struct nft_data data[NFT_REG_MAX + 1],
	30	const struct nft_pktinfo *pkt)
	31	{
	32	const struct nft_byteorder *priv = nft_expr_priv(expr);
	33	struct nft_data src = &data[priv->sreg], dst = &data[priv->dreg];
	34	union { u32 u32; u16 u16; } s, d;
	35	unsigned int i;
	36
	37	s = (void *)src->data;
	38	d = (void *)dst->data;
	39
	40	switch (priv->size) {
	41	case 4:
	42	switch (priv->op) {
	43	case NFT_BYTEORDER_NTOH:
	44	for (i = 0; i < priv->len / 4; i++)
	45	d[i].u32 = ntohl((__force __be32)s[i].u32);
	46	break;
	47	case NFT_BYTEORDER_HTON:
	48	for (i = 0; i < priv->len / 4; i++)
	49	d[i].u32 = (__force __u32)htonl(s[i].u32);
	50	break;
	51	}
	52	break;
	53	case 2:
	54	switch (priv->op) {
	55	case NFT_BYTEORDER_NTOH:
	56	for (i = 0; i < priv->len / 2; i++)
	57	d[i].u16 = ntohs((__force __be16)s[i].u16);
	58	break;
	59	case NFT_BYTEORDER_HTON:
	60	for (i = 0; i < priv->len / 2; i++)
	61	d[i].u16 = (__force __u16)htons(s[i].u16);
	62	break;
	63	}
	64	break;
	65	}
	66	}
67
68	static const struct nla_policy nft_byteorder_policy[NFTA_BYTEORDER_MAX + 1] = {
69	[NFTA_BYTEORDER_SREG] = { .type = NLA_U32 },
70	[NFTA_BYTEORDER_DREG] = { .type = NLA_U32 },
71	[NFTA_BYTEORDER_OP] = { .type = NLA_U32 },
72	[NFTA_BYTEORDER_LEN] = { .type = NLA_U32 },
73	[NFTA_BYTEORDER_SIZE] = { .type = NLA_U32 },
74	};
75
76	static int nft_byteorder_init(const struct nft_ctx *ctx,
77	const struct nft_expr *expr,
78	const struct nlattr * const tb[])
79	{
80	struct nft_byteorder *priv = nft_expr_priv(expr);
81	int err;
82
83	if (tb[NFTA_BYTEORDER_SREG] == NULL \|\|
84	tb[NFTA_BYTEORDER_DREG] == NULL \|\|
85	tb[NFTA_BYTEORDER_LEN] == NULL \|\|
86	tb[NFTA_BYTEORDER_SIZE] == NULL \|\|
87	tb[NFTA_BYTEORDER_OP] == NULL)
88	return -EINVAL;
89
90	priv->sreg = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_SREG]));
91	err = nft_validate_input_register(priv->sreg);
92	if (err < 0)
93	return err;
94
95	priv->dreg = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_DREG]));
96	err = nft_validate_output_register(priv->dreg);
97	if (err < 0)
98	return err;
99	err = nft_validate_data_load(ctx, priv->dreg, NULL, NFT_DATA_VALUE);
100	if (err < 0)
101	return err;
102
103	priv->op = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_OP]));
104	switch (priv->op) {
105	case NFT_BYTEORDER_NTOH:
106	case NFT_BYTEORDER_HTON:
107	break;
108	default:
109	return -EINVAL;
110	}
111
112	priv->len = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_LEN]));
113	if (priv->len == 0 \|\| priv->len > FIELD_SIZEOF(struct nft_data, data))
114	return -EINVAL;
115
116	priv->size = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_SIZE]));
117	switch (priv->size) {
118	case 2:
119	case 4:
120	break;
121	default:
122	return -EINVAL;
123	}
124
125	return 0;
126	}
127
128	static int nft_byteorder_dump(struct sk_buff skb, const struct nft_expr expr)
129	{
130	const struct nft_byteorder *priv = nft_expr_priv(expr);
131
132	if (nla_put_be32(skb, NFTA_BYTEORDER_SREG, htonl(priv->sreg)))
133	goto nla_put_failure;
134	if (nla_put_be32(skb, NFTA_BYTEORDER_DREG, htonl(priv->dreg)))
135	goto nla_put_failure;
136	if (nla_put_be32(skb, NFTA_BYTEORDER_OP, htonl(priv->op)))
137	goto nla_put_failure;
138	if (nla_put_be32(skb, NFTA_BYTEORDER_LEN, htonl(priv->len)))
139	goto nla_put_failure;
140	if (nla_put_be32(skb, NFTA_BYTEORDER_SIZE, htonl(priv->size)))
141	goto nla_put_failure;
142	return 0;
143
144	nla_put_failure:
145	return -1;
146	}
147
ef1f7df9 PM	148	static struct nft_expr_type nft_byteorder_type;
	149	static const struct nft_expr_ops nft_byteorder_ops = {
	150	.type = &nft_byteorder_type,
96518518	151	.size = NFT_EXPR_SIZE(sizeof(struct nft_byteorder)),
96518518 PM	152	.eval = nft_byteorder_eval,
	153	.init = nft_byteorder_init,
	154	.dump = nft_byteorder_dump,
ef1f7df9 PM	155	};
	156
	157	static struct nft_expr_type nft_byteorder_type __read_mostly = {
	158	.name = "byteorder",
	159	.ops = &nft_byteorder_ops,
96518518 PM	160	.policy = nft_byteorder_policy,
96518518 PM	161	.maxattr = NFTA_BYTEORDER_MAX,
ef1f7df9	162	.owner = THIS_MODULE,
96518518 PM	163	};
	164
	165	int __init nft_byteorder_module_init(void)
	166	{
ef1f7df9	167	return nft_register_expr(&nft_byteorder_type);
96518518 PM	168	}
	169
	170	void nft_byteorder_module_exit(void)
	171	{
ef1f7df9	172	nft_unregister_expr(&nft_byteorder_type);
96518518	173	}