[linux-2.6-block.git] / crypto / sha1.c

/*
 * Cryptographic API.
 *
 * SHA1 Secure Hash Algorithm.
 *
 * Derived from cryptoapi implementation, adapted for in-place
 * scatterlist interface.
 *
 * Copyright (c) Alan Smithee.
 * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
 * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
 *
 * 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 <linux/crypto.h>
#include <linux/cryptohash.h>
#include <linux/types.h>
#include <asm/scatterlist.h>
#include <asm/byteorder.h>

#define SHA1_DIGEST_SIZE	20
#define SHA1_HMAC_BLOCK_SIZE	64

struct sha1_ctx {
        u64 count;
        u32 state[5];
        u8 buffer[64];
};

static void sha1_init(void *ctx)
{
	struct sha1_ctx *sctx = ctx;
	static const struct sha1_ctx initstate = {
	  0,
	  { 0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476, 0xC3D2E1F0 },
	  { 0, }
	};

	*sctx = initstate;
}

static void sha1_update(void *ctx, const u8 *data, unsigned int len)
{
	struct sha1_ctx *sctx = ctx;
	unsigned int i, j;
	const u8 *src;

	j = (sctx->count >> 3) & 0x3f;
	sctx->count += len << 3;
	i = 0;
	src = data;

	if ((j + len) > 63) {
		u32 temp[SHA_WORKSPACE_WORDS];

		if (j) {
			memcpy(&sctx->buffer[j], data, (i = 64-j));
			src = sctx->buffer;
		}

		do {
			sha_transform(sctx->state, src, temp);
			i += 64;
			src = &data[i];
		} while (i + 63 < len);

		memset(temp, 0, sizeof(temp));
		j = 0;
	}
	memcpy(&sctx->buffer[j], src, len - i);
}


/* Add padding and return the message digest. */
static void sha1_final(void* ctx, u8 *out)
{
	struct sha1_ctx *sctx = ctx;
	__be32 *dst = (__be32 *)out;
	u32 i, index, padlen;
	__be64 bits;
	static const u8 padding[64] = { 0x80, };

	bits = cpu_to_be64(sctx->count);

	/* Pad out to 56 mod 64 */
	index = (sctx->count >> 3) & 0x3f;
	padlen = (index < 56) ? (56 - index) : ((64+56) - index);
	sha1_update(sctx, padding, padlen);

	/* Append length */
	sha1_update(sctx, (const u8 *)&bits, sizeof(bits));

	/* Store state in digest */
	for (i = 0; i < 5; i++)
		dst[i] = cpu_to_be32(sctx->state[i]);

	/* Wipe context */
	memset(sctx, 0, sizeof *sctx);
}

static struct crypto_alg alg = {
	.cra_name	=	"sha1",
	.cra_flags	=	CRYPTO_ALG_TYPE_DIGEST,
	.cra_blocksize	=	SHA1_HMAC_BLOCK_SIZE,
	.cra_ctxsize	=	sizeof(struct sha1_ctx),
	.cra_module	=	THIS_MODULE,
	.cra_list       =       LIST_HEAD_INIT(alg.cra_list),
	.cra_u		=	{ .digest = {
	.dia_digestsize	=	SHA1_DIGEST_SIZE,
	.dia_init   	= 	sha1_init,
	.dia_update 	=	sha1_update,
	.dia_final  	=	sha1_final } }
};

static int __init init(void)
{
	return crypto_register_alg(&alg);
}

static void __exit fini(void)
{
	crypto_unregister_alg(&alg);
}

module_init(init);
module_exit(fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Cryptographic API.
	3	*
	4	* SHA1 Secure Hash Algorithm.
	5	*
	6	* Derived from cryptoapi implementation, adapted for in-place
	7	* scatterlist interface.
	8	*
	9	* Copyright (c) Alan Smithee.
	10	* Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
	11	* Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
	12	*
	13	* This program is free software; you can redistribute it and/or modify it
	14	* under the terms of the GNU General Public License as published by the Free
	15	* Software Foundation; either version 2 of the License, or (at your option)
	16	* any later version.
	17	*
	18	*/
	19	#include <linux/init.h>
	20	#include <linux/module.h>
	21	#include <linux/mm.h>
	22	#include <linux/crypto.h>
	23	#include <linux/cryptohash.h>
06ace7a9	24	#include <linux/types.h>
1da177e4 LT	25	#include <asm/scatterlist.h>
	26	#include <asm/byteorder.h>
	27
	28	#define SHA1_DIGEST_SIZE 20
	29	#define SHA1_HMAC_BLOCK_SIZE 64
	30
	31	struct sha1_ctx {
	32	u64 count;
	33	u32 state[5];
	34	u8 buffer[64];
	35	};
	36
	37	static void sha1_init(void *ctx)
	38	{
	39	struct sha1_ctx *sctx = ctx;
	40	static const struct sha1_ctx initstate = {
	41	0,
	42	{ 0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476, 0xC3D2E1F0 },
	43	{ 0, }
	44	};
	45
	46	*sctx = initstate;
	47	}
	48
	49	static void sha1_update(void ctx, const u8 data, unsigned int len)
	50	{
	51	struct sha1_ctx *sctx = ctx;
	52	unsigned int i, j;
cfa8d17c	53	const u8 *src;
1da177e4 LT	54
	55	j = (sctx->count >> 3) & 0x3f;
	56	sctx->count += len << 3;
cfa8d17c NP	57	i = 0;
cfa8d17c NP	58	src = data;
1da177e4 LT	59
1da177e4 LT	60	if ((j + len) > 63) {
cfa8d17c NP	61	u32 temp[SHA_WORKSPACE_WORDS];
	62
	63	if (j) {
	64	memcpy(&sctx->buffer[j], data, (i = 64-j));
	65	src = sctx->buffer;
1da177e4	66	}
cfa8d17c NP	67
	68	do {
	69	sha_transform(sctx->state, src, temp);
	70	i += 64;
	71	src = &data[i];
	72	} while (i + 63 < len);
	73
	74	memset(temp, 0, sizeof(temp));
1da177e4 LT	75	j = 0;
1da177e4 LT	76	}
cfa8d17c	77	memcpy(&sctx->buffer[j], src, len - i);
1da177e4 LT	78	}
	79
	80
	81	/* Add padding and return the message digest. */
	82	static void sha1_final(void* ctx, u8 *out)
	83	{
	84	struct sha1_ctx *sctx = ctx;
06ace7a9 HX	85	__be32 dst = (__be32 )out;
	86	u32 i, index, padlen;
	87	__be64 bits;
1da177e4 LT	88	static const u8 padding[64] = { 0x80, };
1da177e4 LT	89
06ace7a9	90	bits = cpu_to_be64(sctx->count);
1da177e4 LT	91
	92	/* Pad out to 56 mod 64 */
	93	index = (sctx->count >> 3) & 0x3f;
	94	padlen = (index < 56) ? (56 - index) : ((64+56) - index);
	95	sha1_update(sctx, padding, padlen);
	96
	97	/* Append length */
06ace7a9	98	sha1_update(sctx, (const u8 *)&bits, sizeof(bits));
1da177e4 LT	99
1da177e4 LT	100	/* Store state in digest */
06ace7a9 HX	101	for (i = 0; i < 5; i++)
06ace7a9 HX	102	dst[i] = cpu_to_be32(sctx->state[i]);
1da177e4 LT	103
	104	/* Wipe context */
	105	memset(sctx, 0, sizeof *sctx);
	106	}
	107
	108	static struct crypto_alg alg = {
	109	.cra_name = "sha1",
	110	.cra_flags = CRYPTO_ALG_TYPE_DIGEST,
	111	.cra_blocksize = SHA1_HMAC_BLOCK_SIZE,
	112	.cra_ctxsize = sizeof(struct sha1_ctx),
	113	.cra_module = THIS_MODULE,
	114	.cra_list = LIST_HEAD_INIT(alg.cra_list),
	115	.cra_u = { .digest = {
	116	.dia_digestsize = SHA1_DIGEST_SIZE,
	117	.dia_init = sha1_init,
	118	.dia_update = sha1_update,
	119	.dia_final = sha1_final } }
	120	};
	121
	122	static int __init init(void)
	123	{
	124	return crypto_register_alg(&alg);
	125	}
	126
	127	static void __exit fini(void)
	128	{
	129	crypto_unregister_alg(&alg);
	130	}
	131
	132	module_init(init);
	133	module_exit(fini);
	134
	135	MODULE_LICENSE("GPL");
	136	MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");