aboutsummaryrefslogtreecommitdiffstats
path: root/crypto/hash.c
blob: f9400a014e74b3bbb3147b046aae36dad6abfad4 (plain) (blame)
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
180
181
182
183
/*
 * Cryptographic Hash operations.
 * 
 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * 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/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/seq_file.h>

#include "internal.h"

static unsigned int crypto_hash_ctxsize(struct crypto_alg *alg, u32 type,
					u32 mask)
{
	return alg->cra_ctxsize;
}

static int hash_setkey_unaligned(struct crypto_hash *crt, const u8 *key,
		                 unsigned int keylen)
{
	struct crypto_tfm *tfm = crypto_hash_tfm(crt);
	struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
	unsigned long alignmask = crypto_hash_alignmask(crt);
	int ret;
	u8 *buffer, *alignbuffer;
	unsigned long absize;

	absize = keylen + alignmask;
	buffer = kmalloc(absize, GFP_ATOMIC);
	if (!buffer)
		return -ENOMEM;

	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	memcpy(alignbuffer, key, keylen);
	ret = alg->setkey(crt, alignbuffer, keylen);
	memset(alignbuffer, 0, keylen);
	kfree(buffer);
	return ret;
}

static int hash_setkey(struct crypto_hash *crt, const u8 *key,
		       unsigned int keylen)
{
	struct crypto_tfm *tfm = crypto_hash_tfm(crt);
	struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
	unsigned long alignmask = crypto_hash_alignmask(crt);

	if ((unsigned long)key & alignmask)
		return hash_setkey_unaligned(crt, key, keylen);

	return alg->setkey(crt, key, keylen);
}

static int hash_async_setkey(struct crypto_ahash *tfm_async, const u8 *key,
			unsigned int keylen)
{
	struct crypto_tfm  *tfm      = crypto_ahash_tfm(tfm_async);
	struct crypto_hash *tfm_hash = __crypto_hash_cast(tfm);
	struct hash_alg    *alg      = &tfm->__crt_alg->cra_hash;

	return alg->setkey(tfm_hash, key, keylen);
}

static int hash_async_init(struct ahash_request *req)
{
	struct crypto_tfm *tfm = req->base.tfm;
	struct hash_alg   *alg = &tfm->__crt_alg->cra_hash;
	struct hash_desc  desc = {
		.tfm = __crypto_hash_cast(tfm),
		.flags = req->base.flags,
	};

	return alg->init(&desc);
}

static int hash_async_update(struct ahash_request *req)
{
	struct crypto_tfm *tfm = req->base.tfm;
	struct hash_alg   *alg = &tfm->__crt_alg->cra_hash;
	struct hash_desc  desc = {
		.tfm = __crypto_hash_cast(tfm),
		.flags = req->base.flags,
	};

	return alg->update(&desc, req->src, req->nbytes);
}

static int hash_async_final(struct ahash_request *req)
{
	struct crypto_tfm *tfm = req->base.tfm;
	struct hash_alg   *alg = &tfm->__crt_alg->cra_hash;
	struct hash_desc  desc = {
		.tfm = __crypto_hash_cast(tfm),
		.flags = req->base.flags,
	};

	return alg->final(&desc, req->result);
}

static int hash_async_digest(struct ahash_request *req)
{
	struct crypto_tfm *tfm = req->base.tfm;
	struct hash_alg   *alg = &tfm->__crt_alg->cra_hash;
	struct hash_desc  desc = {
		.tfm = __crypto_hash_cast(tfm),
		.flags = req->base.flags,
	};

	return alg->digest(&desc, req->src, req->nbytes, req->result);
}

static int crypto_init_hash_ops_async(struct crypto_tfm *tfm)
{
	struct ahash_tfm *crt = &tfm->crt_ahash;
	struct hash_alg  *alg = &tfm->__crt_alg->cra_hash;

	crt->init       = hash_async_init;
	crt->update     = hash_async_update;
	crt->final      = hash_async_final;
	crt->digest     = hash_async_digest;
	crt->setkey     = hash_async_setkey;
	crt->digestsize = alg->digestsize;
	crt->base       = __crypto_ahash_cast(tfm);

	return 0;
}

static int crypto_init_hash_ops_sync(struct crypto_tfm *tfm)
{
	struct hash_tfm *crt = &tfm->crt_hash;
	struct hash_alg *alg = &tfm->__crt_alg->cra_hash;

	crt->init       = alg->init;
	crt->update     = alg->update;
	crt->final      = alg->final;
	crt->digest     = alg->digest;
	crt->setkey     = hash_setkey;
	crt->digestsize = alg->digestsize;

	return 0;
}

static int crypto_init_hash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
{
	struct hash_alg *alg = &tfm->__crt_alg->cra_hash;

	if (alg->digestsize > crypto_tfm_alg_blocksize(tfm))
		return -EINVAL;

	if ((mask & CRYPTO_ALG_TYPE_HASH_MASK) != CRYPTO_ALG_TYPE_HASH_MASK)
		return crypto_init_hash_ops_async(tfm);
	else
		return crypto_init_hash_ops_sync(tfm);
}

static void crypto_hash_show(struct seq_file *m, struct crypto_alg *alg)
	__attribute__ ((unused));
static void crypto_hash_show(struct seq_file *m, struct crypto_alg *alg)
{
	seq_printf(m, "type         : hash\n");
	seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
	seq_printf(m, "digestsize   : %u\n", alg->cra_hash.digestsize);
}

const struct crypto_type crypto_hash_type = {
	.ctxsize = crypto_hash_ctxsize,
	.init = crypto_init_hash_ops,
#ifdef CONFIG_PROC_FS
	.show = crypto_hash_show,
#endif
};
EXPORT_SYMBOL_GPL(crypto_hash_type);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Generic cryptographic hash type");