[net-next-2.6.git] / crypto / tea.c

/* 
 * Cryptographic API.
 *
 * TEA, XTEA, and XETA crypto alogrithms
 *
 * The TEA and Xtended TEA algorithms were developed by David Wheeler 
 * and Roger Needham at the Computer Laboratory of Cambridge University.
 *
 * Due to the order of evaluation in XTEA many people have incorrectly
 * implemented it.  XETA (XTEA in the wrong order), exists for
 * compatibility with these implementations.
 *
 * Copyright (c) 2004 Aaron Grothe ajgrothe@yahoo.com
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <asm/byteorder.h>
#include <linux/crypto.h>
#include <linux/types.h>

#define TEA_KEY_SIZE		16
#define TEA_BLOCK_SIZE		8
#define TEA_ROUNDS		32
#define TEA_DELTA		0x9e3779b9

#define XTEA_KEY_SIZE		16
#define XTEA_BLOCK_SIZE		8
#define XTEA_ROUNDS		32
#define XTEA_DELTA		0x9e3779b9

struct tea_ctx {
	u32 KEY[4];
};

struct xtea_ctx {
	u32 KEY[4];
};

static int tea_setkey(struct crypto_tfm *tfm, const u8 *in_key,
		      unsigned int key_len)
{
	struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
	const __le32 *key = (const __le32 *)in_key;

	ctx->KEY[0] = le32_to_cpu(key[0]);
	ctx->KEY[1] = le32_to_cpu(key[1]);
	ctx->KEY[2] = le32_to_cpu(key[2]);
	ctx->KEY[3] = le32_to_cpu(key[3]);

	return 0; 

}

static void tea_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
	u32 y, z, n, sum = 0;
	u32 k0, k1, k2, k3;
	struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
	const __le32 *in = (const __le32 *)src;
	__le32 *out = (__le32 *)dst;

	y = le32_to_cpu(in[0]);
	z = le32_to_cpu(in[1]);

	k0 = ctx->KEY[0];
	k1 = ctx->KEY[1];
	k2 = ctx->KEY[2];
	k3 = ctx->KEY[3];

	n = TEA_ROUNDS;

	while (n-- > 0) {
		sum += TEA_DELTA;
		y += ((z << 4) + k0) ^ (z + sum) ^ ((z >> 5) + k1);
		z += ((y << 4) + k2) ^ (y + sum) ^ ((y >> 5) + k3);
	}
	
	out[0] = cpu_to_le32(y);
	out[1] = cpu_to_le32(z);
}

static void tea_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
	u32 y, z, n, sum;
	u32 k0, k1, k2, k3;
	struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
	const __le32 *in = (const __le32 *)src;
	__le32 *out = (__le32 *)dst;

	y = le32_to_cpu(in[0]);
	z = le32_to_cpu(in[1]);

	k0 = ctx->KEY[0];
	k1 = ctx->KEY[1];
	k2 = ctx->KEY[2];
	k3 = ctx->KEY[3];

	sum = TEA_DELTA << 5;

	n = TEA_ROUNDS;

	while (n-- > 0) {
		z -= ((y << 4) + k2) ^ (y + sum) ^ ((y >> 5) + k3);
		y -= ((z << 4) + k0) ^ (z + sum) ^ ((z >> 5) + k1);
		sum -= TEA_DELTA;
	}
	
	out[0] = cpu_to_le32(y);
	out[1] = cpu_to_le32(z);
}

static int xtea_setkey(struct crypto_tfm *tfm, const u8 *in_key,
		       unsigned int key_len)
{
	struct xtea_ctx *ctx = crypto_tfm_ctx(tfm);
	const __le32 *key = (const __le32 *)in_key;

	ctx->KEY[0] = le32_to_cpu(key[0]);
	ctx->KEY[1] = le32_to_cpu(key[1]);
	ctx->KEY[2] = le32_to_cpu(key[2]);
	ctx->KEY[3] = le32_to_cpu(key[3]);

	return 0; 

}

static void xtea_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
	u32 y, z, sum = 0;
	u32 limit = XTEA_DELTA * XTEA_ROUNDS;
	struct xtea_ctx *ctx = crypto_tfm_ctx(tfm);
	const __le32 *in = (const __le32 *)src;
	__le32 *out = (__le32 *)dst;

	y = le32_to_cpu(in[0]);
	z = le32_to_cpu(in[1]);

	while (sum != limit) {
		y += ((z << 4 ^ z >> 5) + z) ^ (sum + ctx->KEY[sum&3]); 
		sum += XTEA_DELTA;
		z += ((y << 4 ^ y >> 5) + y) ^ (sum + ctx->KEY[sum>>11 &3]); 
	}
	
	out[0] = cpu_to_le32(y);
	out[1] = cpu_to_le32(z);
}

static void xtea_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
	u32 y, z, sum;
	struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
	const __le32 *in = (const __le32 *)src;
	__le32 *out = (__le32 *)dst;

	y = le32_to_cpu(in[0]);
	z = le32_to_cpu(in[1]);

	sum = XTEA_DELTA * XTEA_ROUNDS;

	while (sum) {
		z -= ((y << 4 ^ y >> 5) + y) ^ (sum + ctx->KEY[sum>>11 & 3]);
		sum -= XTEA_DELTA;
		y -= ((z << 4 ^ z >> 5) + z) ^ (sum + ctx->KEY[sum & 3]);
	}
	
	out[0] = cpu_to_le32(y);
	out[1] = cpu_to_le32(z);
}


static void xeta_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
	u32 y, z, sum = 0;
	u32 limit = XTEA_DELTA * XTEA_ROUNDS;
	struct xtea_ctx *ctx = crypto_tfm_ctx(tfm);
	const __le32 *in = (const __le32 *)src;
	__le32 *out = (__le32 *)dst;

	y = le32_to_cpu(in[0]);
	z = le32_to_cpu(in[1]);

	while (sum != limit) {
		y += (z << 4 ^ z >> 5) + (z ^ sum) + ctx->KEY[sum&3];
		sum += XTEA_DELTA;
		z += (y << 4 ^ y >> 5) + (y ^ sum) + ctx->KEY[sum>>11 &3];
	}
	
	out[0] = cpu_to_le32(y);
	out[1] = cpu_to_le32(z);
}

static void xeta_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
	u32 y, z, sum;
	struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
	const __le32 *in = (const __le32 *)src;
	__le32 *out = (__le32 *)dst;

	y = le32_to_cpu(in[0]);
	z = le32_to_cpu(in[1]);

	sum = XTEA_DELTA * XTEA_ROUNDS;

	while (sum) {
		z -= (y << 4 ^ y >> 5) + (y ^ sum) + ctx->KEY[sum>>11 & 3];
		sum -= XTEA_DELTA;
		y -= (z << 4 ^ z >> 5) + (z ^ sum) + ctx->KEY[sum & 3];
	}
	
	out[0] = cpu_to_le32(y);
	out[1] = cpu_to_le32(z);
}

static struct crypto_alg tea_alg = {
	.cra_name		=	"tea",
	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
	.cra_blocksize		=	TEA_BLOCK_SIZE,
	.cra_ctxsize		=	sizeof (struct tea_ctx),
	.cra_alignmask		=	3,
	.cra_module		=	THIS_MODULE,
	.cra_list		=	LIST_HEAD_INIT(tea_alg.cra_list),
	.cra_u			=	{ .cipher = {
	.cia_min_keysize	=	TEA_KEY_SIZE,
	.cia_max_keysize	=	TEA_KEY_SIZE,
	.cia_setkey		= 	tea_setkey,
	.cia_encrypt		=	tea_encrypt,
	.cia_decrypt		=	tea_decrypt } }
};

static struct crypto_alg xtea_alg = {
	.cra_name		=	"xtea",
	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
	.cra_blocksize		=	XTEA_BLOCK_SIZE,
	.cra_ctxsize		=	sizeof (struct xtea_ctx),
	.cra_alignmask		=	3,
	.cra_module		=	THIS_MODULE,
	.cra_list		=	LIST_HEAD_INIT(xtea_alg.cra_list),
	.cra_u			=	{ .cipher = {
	.cia_min_keysize	=	XTEA_KEY_SIZE,
	.cia_max_keysize	=	XTEA_KEY_SIZE,
	.cia_setkey		= 	xtea_setkey,
	.cia_encrypt		=	xtea_encrypt,
	.cia_decrypt		=	xtea_decrypt } }
};

static struct crypto_alg xeta_alg = {
	.cra_name		=	"xeta",
	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
	.cra_blocksize		=	XTEA_BLOCK_SIZE,
	.cra_ctxsize		=	sizeof (struct xtea_ctx),
	.cra_alignmask		=	3,
	.cra_module		=	THIS_MODULE,
	.cra_list		=	LIST_HEAD_INIT(xtea_alg.cra_list),
	.cra_u			=	{ .cipher = {
	.cia_min_keysize	=	XTEA_KEY_SIZE,
	.cia_max_keysize	=	XTEA_KEY_SIZE,
	.cia_setkey		= 	xtea_setkey,
	.cia_encrypt		=	xeta_encrypt,
	.cia_decrypt		=	xeta_decrypt } }
};

static int __init tea_mod_init(void)
{
	int ret = 0;
	
	ret = crypto_register_alg(&tea_alg);
	if (ret < 0)
		goto out;

	ret = crypto_register_alg(&xtea_alg);
	if (ret < 0) {
		crypto_unregister_alg(&tea_alg);
		goto out;
	}

	ret = crypto_register_alg(&xeta_alg);
	if (ret < 0) {
		crypto_unregister_alg(&tea_alg);
		crypto_unregister_alg(&xtea_alg);
		goto out;
	}

out:	
	return ret;
}

static void __exit tea_mod_fini(void)
{
	crypto_unregister_alg(&tea_alg);
	crypto_unregister_alg(&xtea_alg);
	crypto_unregister_alg(&xeta_alg);
}

MODULE_ALIAS("xtea");
MODULE_ALIAS("xeta");

module_init(tea_mod_init);
module_exit(tea_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("TEA, XTEA & XETA Cryptographic Algorithms");
Commit	Line	Data
	1	/*
	2	* Cryptographic API.
	3	*
	4	* TEA, XTEA, and XETA crypto alogrithms
	5	*
	6	* The TEA and Xtended TEA algorithms were developed by David Wheeler
	7	* and Roger Needham at the Computer Laboratory of Cambridge University.
	8	*
	9	* Due to the order of evaluation in XTEA many people have incorrectly
	10	* implemented it. XETA (XTEA in the wrong order), exists for
	11	* compatibility with these implementations.
	12	*
	13	* Copyright (c) 2004 Aaron Grothe ajgrothe@yahoo.com
	14	*
	15	* This program is free software; you can redistribute it and/or modify
	16	* it under the terms of the GNU General Public License as published by
	17	* the Free Software Foundation; either version 2 of the License, or
	18	* (at your option) any later version.
	19	*
	20	*/
	21
	22	#include <linux/init.h>
	23	#include <linux/module.h>
	24	#include <linux/mm.h>
	25	#include <asm/byteorder.h>
	26	#include <linux/crypto.h>
	27	#include <linux/types.h>
	28
	29	#define TEA_KEY_SIZE 16
	30	#define TEA_BLOCK_SIZE 8
	31	#define TEA_ROUNDS 32
	32	#define TEA_DELTA 0x9e3779b9
	33
	34	#define XTEA_KEY_SIZE 16
	35	#define XTEA_BLOCK_SIZE 8
	36	#define XTEA_ROUNDS 32
	37	#define XTEA_DELTA 0x9e3779b9
	38
	39	struct tea_ctx {
	40	u32 KEY[4];
	41	};
	42
	43	struct xtea_ctx {
	44	u32 KEY[4];
	45	};
	46
	47	static int tea_setkey(struct crypto_tfm tfm, const u8 in_key,
	48	unsigned int key_len)
	49	{
	50	struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
	51	const __le32 key = (const __le32 )in_key;
	52
	53	ctx->KEY[0] = le32_to_cpu(key[0]);
	54	ctx->KEY[1] = le32_to_cpu(key[1]);
	55	ctx->KEY[2] = le32_to_cpu(key[2]);
	56	ctx->KEY[3] = le32_to_cpu(key[3]);
	57
	58	return 0;
	59
	60	}
	61
	62	static void tea_encrypt(struct crypto_tfm tfm, u8 dst, const u8 *src)
	63	{
	64	u32 y, z, n, sum = 0;
	65	u32 k0, k1, k2, k3;
	66	struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
	67	const __le32 in = (const __le32 )src;
	68	__le32 out = (__le32 )dst;
	69
	70	y = le32_to_cpu(in[0]);
	71	z = le32_to_cpu(in[1]);
	72
	73	k0 = ctx->KEY[0];
	74	k1 = ctx->KEY[1];
	75	k2 = ctx->KEY[2];
	76	k3 = ctx->KEY[3];
	77
	78	n = TEA_ROUNDS;
	79
	80	while (n-- > 0) {
	81	sum += TEA_DELTA;
	82	y += ((z << 4) + k0) ^ (z + sum) ^ ((z >> 5) + k1);
	83	z += ((y << 4) + k2) ^ (y + sum) ^ ((y >> 5) + k3);
	84	}
	85
	86	out[0] = cpu_to_le32(y);
	87	out[1] = cpu_to_le32(z);
	88	}
	89
	90	static void tea_decrypt(struct crypto_tfm tfm, u8 dst, const u8 *src)
	91	{
	92	u32 y, z, n, sum;
	93	u32 k0, k1, k2, k3;
	94	struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
	95	const __le32 in = (const __le32 )src;
	96	__le32 out = (__le32 )dst;
	97
	98	y = le32_to_cpu(in[0]);
	99	z = le32_to_cpu(in[1]);
	100
	101	k0 = ctx->KEY[0];
	102	k1 = ctx->KEY[1];
	103	k2 = ctx->KEY[2];
	104	k3 = ctx->KEY[3];
	105
	106	sum = TEA_DELTA << 5;
	107
	108	n = TEA_ROUNDS;
	109
	110	while (n-- > 0) {
	111	z -= ((y << 4) + k2) ^ (y + sum) ^ ((y >> 5) + k3);
	112	y -= ((z << 4) + k0) ^ (z + sum) ^ ((z >> 5) + k1);
	113	sum -= TEA_DELTA;
	114	}
	115
	116	out[0] = cpu_to_le32(y);
	117	out[1] = cpu_to_le32(z);
	118	}
	119
	120	static int xtea_setkey(struct crypto_tfm tfm, const u8 in_key,
	121	unsigned int key_len)
	122	{
	123	struct xtea_ctx *ctx = crypto_tfm_ctx(tfm);
	124	const __le32 key = (const __le32 )in_key;
	125
	126	ctx->KEY[0] = le32_to_cpu(key[0]);
	127	ctx->KEY[1] = le32_to_cpu(key[1]);
	128	ctx->KEY[2] = le32_to_cpu(key[2]);
	129	ctx->KEY[3] = le32_to_cpu(key[3]);
	130
	131	return 0;
	132
	133	}
	134
	135	static void xtea_encrypt(struct crypto_tfm tfm, u8 dst, const u8 *src)
	136	{
	137	u32 y, z, sum = 0;
	138	u32 limit = XTEA_DELTA * XTEA_ROUNDS;
	139	struct xtea_ctx *ctx = crypto_tfm_ctx(tfm);
	140	const __le32 in = (const __le32 )src;
	141	__le32 out = (__le32 )dst;
	142
	143	y = le32_to_cpu(in[0]);
	144	z = le32_to_cpu(in[1]);
	145
	146	while (sum != limit) {
	147	y += ((z << 4 ^ z >> 5) + z) ^ (sum + ctx->KEY[sum&3]);
	148	sum += XTEA_DELTA;
	149	z += ((y << 4 ^ y >> 5) + y) ^ (sum + ctx->KEY[sum>>11 &3]);
	150	}
	151
	152	out[0] = cpu_to_le32(y);
	153	out[1] = cpu_to_le32(z);
	154	}
	155
	156	static void xtea_decrypt(struct crypto_tfm tfm, u8 dst, const u8 *src)
	157	{
	158	u32 y, z, sum;
	159	struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
	160	const __le32 in = (const __le32 )src;
	161	__le32 out = (__le32 )dst;
	162
	163	y = le32_to_cpu(in[0]);
	164	z = le32_to_cpu(in[1]);
	165
	166	sum = XTEA_DELTA * XTEA_ROUNDS;
	167
	168	while (sum) {
	169	z -= ((y << 4 ^ y >> 5) + y) ^ (sum + ctx->KEY[sum>>11 & 3]);
	170	sum -= XTEA_DELTA;
	171	y -= ((z << 4 ^ z >> 5) + z) ^ (sum + ctx->KEY[sum & 3]);
	172	}
	173
	174	out[0] = cpu_to_le32(y);
	175	out[1] = cpu_to_le32(z);
	176	}
	177
	178
	179	static void xeta_encrypt(struct crypto_tfm tfm, u8 dst, const u8 *src)
	180	{
	181	u32 y, z, sum = 0;
	182	u32 limit = XTEA_DELTA * XTEA_ROUNDS;
	183	struct xtea_ctx *ctx = crypto_tfm_ctx(tfm);
	184	const __le32 in = (const __le32 )src;
	185	__le32 out = (__le32 )dst;
	186
	187	y = le32_to_cpu(in[0]);
	188	z = le32_to_cpu(in[1]);
	189
	190	while (sum != limit) {
	191	y += (z << 4 ^ z >> 5) + (z ^ sum) + ctx->KEY[sum&3];
	192	sum += XTEA_DELTA;
	193	z += (y << 4 ^ y >> 5) + (y ^ sum) + ctx->KEY[sum>>11 &3];
	194	}
	195
	196	out[0] = cpu_to_le32(y);
	197	out[1] = cpu_to_le32(z);
	198	}
	199
	200	static void xeta_decrypt(struct crypto_tfm tfm, u8 dst, const u8 *src)
	201	{
	202	u32 y, z, sum;
	203	struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
	204	const __le32 in = (const __le32 )src;
	205	__le32 out = (__le32 )dst;
	206
	207	y = le32_to_cpu(in[0]);
	208	z = le32_to_cpu(in[1]);
	209
	210	sum = XTEA_DELTA * XTEA_ROUNDS;
	211
	212	while (sum) {
	213	z -= (y << 4 ^ y >> 5) + (y ^ sum) + ctx->KEY[sum>>11 & 3];
	214	sum -= XTEA_DELTA;
	215	y -= (z << 4 ^ z >> 5) + (z ^ sum) + ctx->KEY[sum & 3];
	216	}
	217
	218	out[0] = cpu_to_le32(y);
	219	out[1] = cpu_to_le32(z);
	220	}
	221
	222	static struct crypto_alg tea_alg = {
	223	.cra_name = "tea",
	224	.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
	225	.cra_blocksize = TEA_BLOCK_SIZE,
	226	.cra_ctxsize = sizeof (struct tea_ctx),
	227	.cra_alignmask = 3,
	228	.cra_module = THIS_MODULE,
	229	.cra_list = LIST_HEAD_INIT(tea_alg.cra_list),
	230	.cra_u = { .cipher = {
	231	.cia_min_keysize = TEA_KEY_SIZE,
	232	.cia_max_keysize = TEA_KEY_SIZE,
	233	.cia_setkey = tea_setkey,
	234	.cia_encrypt = tea_encrypt,
	235	.cia_decrypt = tea_decrypt } }
	236	};
	237
	238	static struct crypto_alg xtea_alg = {
	239	.cra_name = "xtea",
	240	.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
	241	.cra_blocksize = XTEA_BLOCK_SIZE,
	242	.cra_ctxsize = sizeof (struct xtea_ctx),
	243	.cra_alignmask = 3,
	244	.cra_module = THIS_MODULE,
	245	.cra_list = LIST_HEAD_INIT(xtea_alg.cra_list),
	246	.cra_u = { .cipher = {
	247	.cia_min_keysize = XTEA_KEY_SIZE,
	248	.cia_max_keysize = XTEA_KEY_SIZE,
	249	.cia_setkey = xtea_setkey,
	250	.cia_encrypt = xtea_encrypt,
	251	.cia_decrypt = xtea_decrypt } }
	252	};
	253
	254	static struct crypto_alg xeta_alg = {
	255	.cra_name = "xeta",
	256	.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
	257	.cra_blocksize = XTEA_BLOCK_SIZE,
	258	.cra_ctxsize = sizeof (struct xtea_ctx),
	259	.cra_alignmask = 3,
	260	.cra_module = THIS_MODULE,
	261	.cra_list = LIST_HEAD_INIT(xtea_alg.cra_list),
	262	.cra_u = { .cipher = {
	263	.cia_min_keysize = XTEA_KEY_SIZE,
	264	.cia_max_keysize = XTEA_KEY_SIZE,
	265	.cia_setkey = xtea_setkey,
	266	.cia_encrypt = xeta_encrypt,
	267	.cia_decrypt = xeta_decrypt } }
	268	};
	269
	270	static int __init tea_mod_init(void)
	271	{
	272	int ret = 0;
	273
	274	ret = crypto_register_alg(&tea_alg);
	275	if (ret < 0)
	276	goto out;
	277
	278	ret = crypto_register_alg(&xtea_alg);
	279	if (ret < 0) {
	280	crypto_unregister_alg(&tea_alg);
	281	goto out;
	282	}
	283
	284	ret = crypto_register_alg(&xeta_alg);
	285	if (ret < 0) {
	286	crypto_unregister_alg(&tea_alg);
	287	crypto_unregister_alg(&xtea_alg);
	288	goto out;
	289	}
	290
	291	out:
	292	return ret;
	293	}
	294
	295	static void __exit tea_mod_fini(void)
	296	{
	297	crypto_unregister_alg(&tea_alg);
	298	crypto_unregister_alg(&xtea_alg);
	299	crypto_unregister_alg(&xeta_alg);
	300	}
	301
	302	MODULE_ALIAS("xtea");
	303	MODULE_ALIAS("xeta");
	304
	305	module_init(tea_mod_init);
	306	module_exit(tea_mod_fini);
	307
	308	MODULE_LICENSE("GPL");
	309	MODULE_DESCRIPTION("TEA, XTEA & XETA Cryptographic Algorithms");