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
|
/*
* Cryptographic API.
*
* HMAC: Keyed-Hashing for Message Authentication (RFC2104).
*
* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
*
* The HMAC implementation is derived from USAGI.
* Copyright (c) 2002 Kazunori Miyazawa <miyazawa@linux-ipv6.org> / USAGI
*
* 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/crypto.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/slab.h>
#include <asm/scatterlist.h>
#include "internal.h"
static void hash_key(struct crypto_tfm *tfm, u8 *key, unsigned int keylen)
{
struct scatterlist tmp;
tmp.page = virt_to_page(key);
tmp.offset = offset_in_page(key);
tmp.length = keylen;
crypto_digest_digest(tfm, &tmp, 1, key);
}
int crypto_alloc_hmac_block(struct crypto_tfm *tfm)
{
int ret = 0;
BUG_ON(!crypto_tfm_alg_blocksize(tfm));
tfm->crt_digest.dit_hmac_block = kmalloc(crypto_tfm_alg_blocksize(tfm),
GFP_KERNEL);
if (tfm->crt_digest.dit_hmac_block == NULL)
ret = -ENOMEM;
return ret;
}
void crypto_free_hmac_block(struct crypto_tfm *tfm)
{
if (tfm->crt_digest.dit_hmac_block)
kfree(tfm->crt_digest.dit_hmac_block);
}
void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen)
{
unsigned int i;
struct scatterlist tmp;
char *ipad = tfm->crt_digest.dit_hmac_block;
if (*keylen > crypto_tfm_alg_blocksize(tfm)) {
hash_key(tfm, key, *keylen);
*keylen = crypto_tfm_alg_digestsize(tfm);
}
memset(ipad, 0, crypto_tfm_alg_blocksize(tfm));
memcpy(ipad, key, *keylen);
for (i = 0; i < crypto_tfm_alg_blocksize(tfm); i++)
ipad[i] ^= 0x36;
tmp.page = virt_to_page(ipad);
tmp.offset = offset_in_page(ipad);
tmp.length = crypto_tfm_alg_blocksize(tfm);
crypto_digest_init(tfm);
crypto_digest_update(tfm, &tmp, 1);
}
void crypto_hmac_update(struct crypto_tfm *tfm,
struct scatterlist *sg, unsigned int nsg)
{
crypto_digest_update(tfm, sg, nsg);
}
void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
unsigned int *keylen, u8 *out)
{
unsigned int i;
struct scatterlist tmp;
char *opad = tfm->crt_digest.dit_hmac_block;
if (*keylen > crypto_tfm_alg_blocksize(tfm)) {
hash_key(tfm, key, *keylen);
*keylen = crypto_tfm_alg_digestsize(tfm);
}
crypto_digest_final(tfm, out);
memset(opad, 0, crypto_tfm_alg_blocksize(tfm));
memcpy(opad, key, *keylen);
for (i = 0; i < crypto_tfm_alg_blocksize(tfm); i++)
opad[i] ^= 0x5c;
tmp.page = virt_to_page(opad);
tmp.offset = offset_in_page(opad);
tmp.length = crypto_tfm_alg_blocksize(tfm);
crypto_digest_init(tfm);
crypto_digest_update(tfm, &tmp, 1);
tmp.page = virt_to_page(out);
tmp.offset = offset_in_page(out);
tmp.length = crypto_tfm_alg_digestsize(tfm);
crypto_digest_update(tfm, &tmp, 1);
crypto_digest_final(tfm, out);
}
void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
struct scatterlist *sg, unsigned int nsg, u8 *out)
{
crypto_hmac_init(tfm, key, keylen);
crypto_hmac_update(tfm, sg, nsg);
crypto_hmac_final(tfm, key, keylen, out);
}
EXPORT_SYMBOL_GPL(crypto_hmac_init);
EXPORT_SYMBOL_GPL(crypto_hmac_update);
EXPORT_SYMBOL_GPL(crypto_hmac_final);
EXPORT_SYMBOL_GPL(crypto_hmac);
|
