[net-next-2.6.git] / crypto / sha1_generic.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 <crypto/internal/hash.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/cryptohash.h>
#include <linux/types.h>
#include <crypto/sha.h>
#include <asm/byteorder.h>

static int sha1_init(struct shash_desc *desc)
{
	struct sha1_state *sctx = shash_desc_ctx(desc);

	*sctx = (struct sha1_state){
		.state = { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 },
	};

	return 0;
}

static int sha1_update(struct shash_desc *desc, const u8 *data,
			unsigned int len)
{
	struct sha1_state *sctx = shash_desc_ctx(desc);
	unsigned int partial, done;
	const u8 *src;

	partial = sctx->count & 0x3f;
	sctx->count += len;
	done = 0;
	src = data;

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

		if (partial) {
			done = -partial;
			memcpy(sctx->buffer + partial, data, done + 64);
			src = sctx->buffer;
		}

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

		memset(temp, 0, sizeof(temp));
		partial = 0;
	}
	memcpy(sctx->buffer + partial, src, len - done);

	return 0;
}


/* Add padding and return the message digest. */
static int sha1_final(struct shash_desc *desc, u8 *out)
{
	struct sha1_state *sctx = shash_desc_ctx(desc);
	__be32 *dst = (__be32 *)out;
	u32 i, index, padlen;
	__be64 bits;
	static const u8 padding[64] = { 0x80, };

	bits = cpu_to_be64(sctx->count << 3);

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

	/* Append length */
	sha1_update(desc, (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);

	return 0;
}

static int sha1_export(struct shash_desc *desc, void *out)
{
	struct sha1_state *sctx = shash_desc_ctx(desc);

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

static int sha1_import(struct shash_desc *desc, const void *in)
{
	struct sha1_state *sctx = shash_desc_ctx(desc);

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

static struct shash_alg alg = {
	.digestsize	=	SHA1_DIGEST_SIZE,
	.init		=	sha1_init,
	.update		=	sha1_update,
	.final		=	sha1_final,
	.export		=	sha1_export,
	.import		=	sha1_import,
	.descsize	=	sizeof(struct sha1_state),
	.statesize	=	sizeof(struct sha1_state),
	.base		=	{
		.cra_name	=	"sha1",
		.cra_driver_name=	"sha1-generic",
		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
		.cra_blocksize	=	SHA1_BLOCK_SIZE,
		.cra_module	=	THIS_MODULE,
	}
};

static int __init sha1_generic_mod_init(void)
{
	return crypto_register_shash(&alg);
}

static void __exit sha1_generic_mod_fini(void)
{
	crypto_unregister_shash(&alg);
}

module_init(sha1_generic_mod_init);
module_exit(sha1_generic_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");

MODULE_ALIAS("sha1");
Commit	Line	Data
	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 <crypto/internal/hash.h>
	20	#include <linux/init.h>
	21	#include <linux/module.h>
	22	#include <linux/mm.h>
	23	#include <linux/cryptohash.h>
	24	#include <linux/types.h>
	25	#include <crypto/sha.h>
	26	#include <asm/byteorder.h>
	27
	28	static int sha1_init(struct shash_desc *desc)
	29	{
	30	struct sha1_state *sctx = shash_desc_ctx(desc);
	31
	32	*sctx = (struct sha1_state){
	33	.state = { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 },
	34	};
	35
	36	return 0;
	37	}
	38
	39	static int sha1_update(struct shash_desc desc, const u8 data,
	40	unsigned int len)
	41	{
	42	struct sha1_state *sctx = shash_desc_ctx(desc);
	43	unsigned int partial, done;
	44	const u8 *src;
	45
	46	partial = sctx->count & 0x3f;
	47	sctx->count += len;
	48	done = 0;
	49	src = data;
	50
	51	if ((partial + len) > 63) {
	52	u32 temp[SHA_WORKSPACE_WORDS];
	53
	54	if (partial) {
	55	done = -partial;
	56	memcpy(sctx->buffer + partial, data, done + 64);
	57	src = sctx->buffer;
	58	}
	59
	60	do {
	61	sha_transform(sctx->state, src, temp);
	62	done += 64;
	63	src = data + done;
	64	} while (done + 63 < len);
	65
	66	memset(temp, 0, sizeof(temp));
	67	partial = 0;
	68	}
	69	memcpy(sctx->buffer + partial, src, len - done);
	70
	71	return 0;
	72	}
	73
	74
	75	/* Add padding and return the message digest. */
	76	static int sha1_final(struct shash_desc desc, u8 out)
	77	{
	78	struct sha1_state *sctx = shash_desc_ctx(desc);
	79	__be32 dst = (__be32 )out;
	80	u32 i, index, padlen;
	81	__be64 bits;
	82	static const u8 padding[64] = { 0x80, };
	83
	84	bits = cpu_to_be64(sctx->count << 3);
	85
	86	/* Pad out to 56 mod 64 */
	87	index = sctx->count & 0x3f;
	88	padlen = (index < 56) ? (56 - index) : ((64+56) - index);
	89	sha1_update(desc, padding, padlen);
	90
	91	/* Append length */
	92	sha1_update(desc, (const u8 *)&bits, sizeof(bits));
	93
	94	/* Store state in digest */
	95	for (i = 0; i < 5; i++)
	96	dst[i] = cpu_to_be32(sctx->state[i]);
	97
	98	/* Wipe context */
	99	memset(sctx, 0, sizeof *sctx);
	100
	101	return 0;
	102	}
	103
	104	static int sha1_export(struct shash_desc desc, void out)
	105	{
	106	struct sha1_state *sctx = shash_desc_ctx(desc);
	107
	108	memcpy(out, sctx, sizeof(*sctx));
	109	return 0;
	110	}
	111
	112	static int sha1_import(struct shash_desc desc, const void in)
	113	{
	114	struct sha1_state *sctx = shash_desc_ctx(desc);
	115
	116	memcpy(sctx, in, sizeof(*sctx));
	117	return 0;
	118	}
	119
	120	static struct shash_alg alg = {
	121	.digestsize = SHA1_DIGEST_SIZE,
	122	.init = sha1_init,
	123	.update = sha1_update,
	124	.final = sha1_final,
	125	.export = sha1_export,
	126	.import = sha1_import,
	127	.descsize = sizeof(struct sha1_state),
	128	.statesize = sizeof(struct sha1_state),
	129	.base = {
	130	.cra_name = "sha1",
	131	.cra_driver_name= "sha1-generic",
	132	.cra_flags = CRYPTO_ALG_TYPE_SHASH,
	133	.cra_blocksize = SHA1_BLOCK_SIZE,
	134	.cra_module = THIS_MODULE,
	135	}
	136	};
	137
	138	static int __init sha1_generic_mod_init(void)
	139	{
	140	return crypto_register_shash(&alg);
	141	}
	142
	143	static void __exit sha1_generic_mod_fini(void)
	144	{
	145	crypto_unregister_shash(&alg);
	146	}
	147
	148	module_init(sha1_generic_mod_init);
	149	module_exit(sha1_generic_mod_fini);
	150
	151	MODULE_LICENSE("GPL");
	152	MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");
	153
	154	MODULE_ALIAS("sha1");