[deliverable/linux.git] / crypto / md5.c

/* 
 * Cryptographic API.
 *
 * MD5 Message Digest Algorithm (RFC1321).
 *
 * Derived from cryptoapi implementation, originally based on the
 * public domain implementation written by Colin Plumb in 1993.
 *
 * Copyright (c) Cryptoapi developers.
 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
 * 
 * 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 <crypto/internal/hash.h>
#include <crypto/md5.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/cryptohash.h>
#include <asm/byteorder.h>

const u8 md5_zero_message_hash[MD5_DIGEST_SIZE] = {
	0xd4, 0x1d, 0x8c, 0xd9, 0x8f, 0x00, 0xb2, 0x04,
	0xe9, 0x80, 0x09, 0x98, 0xec, 0xf8, 0x42, 0x7e,
};
EXPORT_SYMBOL_GPL(md5_zero_message_hash);

/* XXX: this stuff can be optimized */
static inline void le32_to_cpu_array(u32 *buf, unsigned int words)
{
	while (words--) {
		__le32_to_cpus(buf);
		buf++;
	}
}

static inline void cpu_to_le32_array(u32 *buf, unsigned int words)
{
	while (words--) {
		__cpu_to_le32s(buf);
		buf++;
	}
}

static inline void md5_transform_helper(struct md5_state *ctx)
{
	le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32));
	md5_transform(ctx->hash, ctx->block);
}

static int md5_init(struct shash_desc *desc)
{
	struct md5_state *mctx = shash_desc_ctx(desc);

	mctx->hash[0] = MD5_H0;
	mctx->hash[1] = MD5_H1;
	mctx->hash[2] = MD5_H2;
	mctx->hash[3] = MD5_H3;
	mctx->byte_count = 0;

	return 0;
}

static int md5_update(struct shash_desc *desc, const u8 *data, unsigned int len)
{
	struct md5_state *mctx = shash_desc_ctx(desc);
	const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);

	mctx->byte_count += len;

	if (avail > len) {
		memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
		       data, len);
		return 0;
	}

	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
	       data, avail);

	md5_transform_helper(mctx);
	data += avail;
	len -= avail;

	while (len >= sizeof(mctx->block)) {
		memcpy(mctx->block, data, sizeof(mctx->block));
		md5_transform_helper(mctx);
		data += sizeof(mctx->block);
		len -= sizeof(mctx->block);
	}

	memcpy(mctx->block, data, len);

	return 0;
}

static int md5_final(struct shash_desc *desc, u8 *out)
{
	struct md5_state *mctx = shash_desc_ctx(desc);
	const unsigned int offset = mctx->byte_count & 0x3f;
	char *p = (char *)mctx->block + offset;
	int padding = 56 - (offset + 1);

	*p++ = 0x80;
	if (padding < 0) {
		memset(p, 0x00, padding + sizeof (u64));
		md5_transform_helper(mctx);
		p = (char *)mctx->block;
		padding = 56;
	}

	memset(p, 0, padding);
	mctx->block[14] = mctx->byte_count << 3;
	mctx->block[15] = mctx->byte_count >> 29;
	le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
	                  sizeof(u64)) / sizeof(u32));
	md5_transform(mctx->hash, mctx->block);
	cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32));
	memcpy(out, mctx->hash, sizeof(mctx->hash));
	memset(mctx, 0, sizeof(*mctx));

	return 0;
}

static int md5_export(struct shash_desc *desc, void *out)
{
	struct md5_state *ctx = shash_desc_ctx(desc);

	memcpy(out, ctx, sizeof(*ctx));
	return 0;
}

static int md5_import(struct shash_desc *desc, const void *in)
{
	struct md5_state *ctx = shash_desc_ctx(desc);

	memcpy(ctx, in, sizeof(*ctx));
	return 0;
}

static struct shash_alg alg = {
	.digestsize	=	MD5_DIGEST_SIZE,
	.init		=	md5_init,
	.update		=	md5_update,
	.final		=	md5_final,
	.export		=	md5_export,
	.import		=	md5_import,
	.descsize	=	sizeof(struct md5_state),
	.statesize	=	sizeof(struct md5_state),
	.base		=	{
		.cra_name	=	"md5",
		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
		.cra_blocksize	=	MD5_HMAC_BLOCK_SIZE,
		.cra_module	=	THIS_MODULE,
	}
};

static int __init md5_mod_init(void)
{
	return crypto_register_shash(&alg);
}

static void __exit md5_mod_fini(void)
{
	crypto_unregister_shash(&alg);
}

module_init(md5_mod_init);
module_exit(md5_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MD5 Message Digest Algorithm");
MODULE_ALIAS_CRYPTO("md5");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Cryptographic API.
	3	*
	4	* MD5 Message Digest Algorithm (RFC1321).
	5	*
	6	* Derived from cryptoapi implementation, originally based on the
	7	* public domain implementation written by Colin Plumb in 1993.
	8	*
	9	* Copyright (c) Cryptoapi developers.
	10	* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
	11	*
	12	* This program is free software; you can redistribute it and/or modify it
	13	* under the terms of the GNU General Public License as published by the Free
	14	* Software Foundation; either version 2 of the License, or (at your option)
	15	* any later version.
	16	*
	17	*/
14b75ba7	18	#include <crypto/internal/hash.h>
7d6f75eb	19	#include <crypto/md5.h>
1da177e4 LT	20	#include <linux/init.h>
	21	#include <linux/module.h>
	22	#include <linux/string.h>
06ace7a9	23	#include <linux/types.h>
bc0b96b5	24	#include <linux/cryptohash.h>
1da177e4 LT	25	#include <asm/byteorder.h>
1da177e4 LT	26
0c4c78de LC	27	const u8 md5_zero_message_hash[MD5_DIGEST_SIZE] = {
	28	0xd4, 0x1d, 0x8c, 0xd9, 0x8f, 0x00, 0xb2, 0x04,
	29	0xe9, 0x80, 0x09, 0x98, 0xec, 0xf8, 0x42, 0x7e,
	30	};
	31	EXPORT_SYMBOL_GPL(md5_zero_message_hash);
	32
1da177e4 LT	33	/* XXX: this stuff can be optimized */
	34	static inline void le32_to_cpu_array(u32 *buf, unsigned int words)
	35	{
	36	while (words--) {
	37	__le32_to_cpus(buf);
	38	buf++;
	39	}
	40	}
	41
	42	static inline void cpu_to_le32_array(u32 *buf, unsigned int words)
	43	{
	44	while (words--) {
	45	__cpu_to_le32s(buf);
	46	buf++;
	47	}
	48	}
	49
7d6f75eb	50	static inline void md5_transform_helper(struct md5_state *ctx)
1da177e4 LT	51	{
	52	le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32));
	53	md5_transform(ctx->hash, ctx->block);
	54	}
	55
14b75ba7	56	static int md5_init(struct shash_desc *desc)
1da177e4	57	{
7d6f75eb	58	struct md5_state *mctx = shash_desc_ctx(desc);
1da177e4	59
6a185016 LC	60	mctx->hash[0] = MD5_H0;
	61	mctx->hash[1] = MD5_H1;
	62	mctx->hash[2] = MD5_H2;
	63	mctx->hash[3] = MD5_H3;
1da177e4	64	mctx->byte_count = 0;
14b75ba7 AKR	65
14b75ba7 AKR	66	return 0;
1da177e4 LT	67	}
1da177e4 LT	68
14b75ba7	69	static int md5_update(struct shash_desc desc, const u8 data, unsigned int len)
1da177e4	70	{
7d6f75eb	71	struct md5_state *mctx = shash_desc_ctx(desc);
1da177e4 LT	72	const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
	73
	74	mctx->byte_count += len;
	75
	76	if (avail > len) {
	77	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
	78	data, len);
14b75ba7	79	return 0;
1da177e4 LT	80	}
	81
	82	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
	83	data, avail);
	84
	85	md5_transform_helper(mctx);
	86	data += avail;
	87	len -= avail;
	88
	89	while (len >= sizeof(mctx->block)) {
	90	memcpy(mctx->block, data, sizeof(mctx->block));
	91	md5_transform_helper(mctx);
	92	data += sizeof(mctx->block);
	93	len -= sizeof(mctx->block);
	94	}
	95
	96	memcpy(mctx->block, data, len);
14b75ba7 AKR	97
14b75ba7 AKR	98	return 0;
1da177e4 LT	99	}
1da177e4 LT	100
14b75ba7	101	static int md5_final(struct shash_desc desc, u8 out)
1da177e4	102	{
7d6f75eb	103	struct md5_state *mctx = shash_desc_ctx(desc);
1da177e4 LT	104	const unsigned int offset = mctx->byte_count & 0x3f;
	105	char p = (char )mctx->block + offset;
	106	int padding = 56 - (offset + 1);
	107
	108	*p++ = 0x80;
	109	if (padding < 0) {
	110	memset(p, 0x00, padding + sizeof (u64));
	111	md5_transform_helper(mctx);
	112	p = (char *)mctx->block;
	113	padding = 56;
	114	}
	115
	116	memset(p, 0, padding);
	117	mctx->block[14] = mctx->byte_count << 3;
	118	mctx->block[15] = mctx->byte_count >> 29;
	119	le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
	120	sizeof(u64)) / sizeof(u32));
	121	md5_transform(mctx->hash, mctx->block);
	122	cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32));
	123	memcpy(out, mctx->hash, sizeof(mctx->hash));
	124	memset(mctx, 0, sizeof(*mctx));
14b75ba7 AKR	125
14b75ba7 AKR	126	return 0;
1da177e4 LT	127	}
1da177e4 LT	128
7d6f75eb MV	129	static int md5_export(struct shash_desc desc, void out)
	130	{
	131	struct md5_state *ctx = shash_desc_ctx(desc);
	132
	133	memcpy(out, ctx, sizeof(*ctx));
	134	return 0;
	135	}
	136
	137	static int md5_import(struct shash_desc desc, const void in)
	138	{
	139	struct md5_state *ctx = shash_desc_ctx(desc);
	140
	141	memcpy(ctx, in, sizeof(*ctx));
	142	return 0;
	143	}
	144
14b75ba7 AKR	145	static struct shash_alg alg = {
	146	.digestsize = MD5_DIGEST_SIZE,
	147	.init = md5_init,
	148	.update = md5_update,
	149	.final = md5_final,
7d6f75eb MV	150	.export = md5_export,
	151	.import = md5_import,
	152	.descsize = sizeof(struct md5_state),
eebb111f	153	.statesize = sizeof(struct md5_state),
14b75ba7 AKR	154	.base = {
	155	.cra_name = "md5",
	156	.cra_flags = CRYPTO_ALG_TYPE_SHASH,
	157	.cra_blocksize = MD5_HMAC_BLOCK_SIZE,
	158	.cra_module = THIS_MODULE,
	159	}
1da177e4 LT	160	};
1da177e4 LT	161
3af5b90b	162	static int __init md5_mod_init(void)
1da177e4	163	{
14b75ba7	164	return crypto_register_shash(&alg);
1da177e4 LT	165	}
1da177e4 LT	166
3af5b90b	167	static void __exit md5_mod_fini(void)
1da177e4	168	{
14b75ba7	169	crypto_unregister_shash(&alg);
1da177e4 LT	170	}
1da177e4 LT	171
3af5b90b KB	172	module_init(md5_mod_init);
3af5b90b KB	173	module_exit(md5_mod_fini);
1da177e4 LT	174
	175	MODULE_LICENSE("GPL");
	176	MODULE_DESCRIPTION("MD5 Message Digest Algorithm");
5d26a105	177	MODULE_ALIAS_CRYPTO("md5");