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
|
/*
* 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 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);
}
/* 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 << 3);
/* Pad out to 56 mod 64 */
index = sctx->count & 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");
|
