aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/crypto/sha1_glue.c
blob: 76cd976230bc4b7558c18a50daaa5278fe85565f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
/*
 * Cryptographic API.
 * Glue code for the SHA1 Secure Hash Algorithm assembler implementation
 *
 * This file is based on sha1_generic.c and sha1_ssse3_glue.c
 *
 * Copyright (c) Alan Smithee.
 * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
 * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
 * Copyright (c) Mathias Krause <minipli@googlemail.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 <crypto/internal/hash.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/cryptohash.h>
#include <linux/types.h>
#include <crypto/sha.h>
#include <asm/byteorder.h>

struct SHA1_CTX {
	uint32_t h0,h1,h2,h3,h4;
	u64 count;
	u8 data[SHA1_BLOCK_SIZE];
};

asmlinkage void sha1_block_data_order(struct SHA1_CTX *digest,
		const unsigned char *data, unsigned int rounds);


static int sha1_init(struct shash_desc *desc)
{
	struct SHA1_CTX *sctx = shash_desc_ctx(desc);
	memset(sctx, 0, sizeof(*sctx));
	sctx->h0 = SHA1_H0;
	sctx->h1 = SHA1_H1;
	sctx->h2 = SHA1_H2;
	sctx->h3 = SHA1_H3;
	sctx->h4 = SHA1_H4;
	return 0;
}


static int __sha1_update(struct SHA1_CTX *sctx, const u8 *data,
			       unsigned int len, unsigned int partial)
{
	unsigned int done = 0;

	sctx->count += len;

	if (partial) {
		done = SHA1_BLOCK_SIZE - partial;
		memcpy(sctx->data + partial, data, done);
		sha1_block_data_order(sctx, sctx->data, 1);
	}

	if (len - done >= SHA1_BLOCK_SIZE) {
		const unsigned int rounds = (len - done) / SHA1_BLOCK_SIZE;
		sha1_block_data_order(sctx, data + done, rounds);
		done += rounds * SHA1_BLOCK_SIZE;
	}

	memcpy(sctx->data, data + done, len - done);
	return 0;
}


static int sha1_update(struct shash_desc *desc, const u8 *data,
			     unsigned int len)
{
	struct SHA1_CTX *sctx = shash_desc_ctx(desc);
	unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;
	int res;

	/* Handle the fast case right here */
	if (partial + len < SHA1_BLOCK_SIZE) {
		sctx->count += len;
		memcpy(sctx->data + partial, data, len);
		return 0;
	}
	res = __sha1_update(sctx, data, len, partial);
	return res;
}


/* Add padding and return the message digest. */
static int sha1_final(struct shash_desc *desc, u8 *out)
{
	struct SHA1_CTX *sctx = shash_desc_ctx(desc);
	unsigned int i, index, padlen;
	__be32 *dst = (__be32 *)out;
	__be64 bits;
	static const u8 padding[SHA1_BLOCK_SIZE] = { 0x80, };

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

	/* Pad out to 56 mod 64 and append length */
	index = sctx->count % SHA1_BLOCK_SIZE;
	padlen = (index < 56) ? (56 - index) : ((SHA1_BLOCK_SIZE+56) - index);
	/* We need to fill a whole block for __sha1_update() */
	if (padlen <= 56) {
		sctx->count += padlen;
		memcpy(sctx->data + index, padding, padlen);
	} else {
		__sha1_update(sctx, padding, padlen, index);
	}
	__sha1_update(sctx, (const u8 *)&bits, sizeof(bits), 56);

	/* Store state in digest */
	for (i = 0; i < 5; i++)
		dst[i] = cpu_to_be32(((u32 *)sctx)[i]);

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


static int sha1_export(struct shash_desc *desc, void *out)
{
	struct SHA1_CTX *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_CTX *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_CTX),
	.statesize	=	sizeof(struct SHA1_CTX),
	.base		=	{
		.cra_name	=	"sha1",
		.cra_driver_name=	"sha1-asm",
		.cra_priority	=	150,
		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
		.cra_blocksize	=	SHA1_BLOCK_SIZE,
		.cra_module	=	THIS_MODULE,
	}
};


static int __init sha1_mod_init(void)
{
	return crypto_register_shash(&alg);
}


static void __exit sha1_mod_fini(void)
{
	crypto_unregister_shash(&alg);
}


module_init(sha1_mod_init);
module_exit(sha1_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm (ARM)");
MODULE_ALIAS("sha1");
MODULE_AUTHOR("David McCullough <ucdevel@gmail.com>");