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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 <[email protected]>
	11	* Copyright (c) Jean-Francois Dive <[email protected]>
	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	int crypto_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 % SHA1_BLOCK_SIZE;
	47	sctx->count += len;
	48	done = 0;
	49	src = data;
	50
	51	if ((partial + len) >= SHA1_BLOCK_SIZE) {
	52	u32 temp[SHA_WORKSPACE_WORDS];
	53
	54	if (partial) {
	55	done = -partial;
	56	memcpy(sctx->buffer + partial, data,
	57	done + SHA1_BLOCK_SIZE);
	58	src = sctx->buffer;
	59	}
	60
	61	do {
	62	sha_transform(sctx->state, src, temp);
	63	done += SHA1_BLOCK_SIZE;
	64	src = data + done;
	65	} while (done + SHA1_BLOCK_SIZE <= len);
	66
	67	memset(temp, 0, sizeof(temp));
	68	partial = 0;
	69	}
	70	memcpy(sctx->buffer + partial, src, len - done);
	71
	72	return 0;
	73	}
	74	EXPORT_SYMBOL(crypto_sha1_update);
	75
	76
	77	/* Add padding and return the message digest. */
	78	static int sha1_final(struct shash_desc desc, u8 out)
	79	{
	80	struct sha1_state *sctx = shash_desc_ctx(desc);
	81	__be32 dst = (__be32 )out;
	82	u32 i, index, padlen;
	83	__be64 bits;
	84	static const u8 padding[64] = { 0x80, };
	85
	86	bits = cpu_to_be64(sctx->count << 3);
	87
	88	/* Pad out to 56 mod 64 */
	89	index = sctx->count & 0x3f;
	90	padlen = (index < 56) ? (56 - index) : ((64+56) - index);
	91	crypto_sha1_update(desc, padding, padlen);
	92
	93	/* Append length */
	94	crypto_sha1_update(desc, (const u8 *)&bits, sizeof(bits));
	95
	96	/* Store state in digest */
	97	for (i = 0; i < 5; i++)
	98	dst[i] = cpu_to_be32(sctx->state[i]);
	99
	100	/* Wipe context */
	101	memset(sctx, 0, sizeof *sctx);
	102
	103	return 0;
	104	}
	105
	106	static int sha1_export(struct shash_desc desc, void out)
	107	{
	108	struct sha1_state *sctx = shash_desc_ctx(desc);
	109
	110	memcpy(out, sctx, sizeof(*sctx));
	111	return 0;
	112	}
	113
	114	static int sha1_import(struct shash_desc desc, const void in)
	115	{
	116	struct sha1_state *sctx = shash_desc_ctx(desc);
	117
	118	memcpy(sctx, in, sizeof(*sctx));
	119	return 0;
	120	}
	121
	122	static struct shash_alg alg = {
	123	.digestsize = SHA1_DIGEST_SIZE,
	124	.init = sha1_init,
	125	.update = crypto_sha1_update,
	126	.final = sha1_final,
	127	.export = sha1_export,
	128	.import = sha1_import,
	129	.descsize = sizeof(struct sha1_state),
	130	.statesize = sizeof(struct sha1_state),
	131	.base = {
	132	.cra_name = "sha1",
	133	.cra_driver_name= "sha1-generic",
	134	.cra_flags = CRYPTO_ALG_TYPE_SHASH,
	135	.cra_blocksize = SHA1_BLOCK_SIZE,
	136	.cra_module = THIS_MODULE,
	137	}
	138	};
	139
	140	static int __init sha1_generic_mod_init(void)
	141	{
	142	return crypto_register_shash(&alg);
	143	}
	144
	145	static void __exit sha1_generic_mod_fini(void)
	146	{
	147	crypto_unregister_shash(&alg);
	148	}
	149
	150	module_init(sha1_generic_mod_init);
	151	module_exit(sha1_generic_mod_fini);
	152
	153	MODULE_LICENSE("GPL");
	154	MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");
	155
	156	MODULE_ALIAS("sha1");