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
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Cryptographic API.
*
* Null algorithms, aka Much Ado About Nothing.
*
* These are needed for IPsec, and may be useful in general for
* testing & debugging.
*
* The null cipher is compliant with RFC2410.
*
* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
*/
#include <crypto/null.h>
#include <crypto/internal/hash.h>
#include <crypto/internal/skcipher.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/string.h>
static DEFINE_MUTEX(crypto_default_null_skcipher_lock);
static struct crypto_sync_skcipher *crypto_default_null_skcipher;
static int crypto_default_null_skcipher_refcnt;
static int null_compress(struct crypto_tfm *tfm, const u8 *src,
unsigned int slen, u8 *dst, unsigned int *dlen)
{
if (slen > *dlen)
return -EINVAL;
memcpy(dst, src, slen);
*dlen = slen;
return 0;
}
static int null_init(struct shash_desc *desc)
{
return 0;
}
static int null_update(struct shash_desc *desc, const u8 *data,
unsigned int len)
{
return 0;
}
static int null_final(struct shash_desc *desc, u8 *out)
{
return 0;
}
static int null_digest(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out)
{
return 0;
}
static int null_hash_setkey(struct crypto_shash *tfm, const u8 *key,
unsigned int keylen)
{ return 0; }
static int null_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
unsigned int keylen)
{ return 0; }
static int null_setkey(struct crypto_tfm *tfm, const u8 *key,
unsigned int keylen)
{ return 0; }
static void null_crypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
memcpy(dst, src, NULL_BLOCK_SIZE);
}
static int null_skcipher_crypt(struct skcipher_request *req)
{
struct skcipher_walk walk;
int err;
err = skcipher_walk_virt(&walk, req, false);
while (walk.nbytes) {
if (walk.src.virt.addr != walk.dst.virt.addr)
memcpy(walk.dst.virt.addr, walk.src.virt.addr,
walk.nbytes);
err = skcipher_walk_done(&walk, 0);
}
return err;
}
static struct shash_alg digest_null = {
.digestsize = NULL_DIGEST_SIZE,
.setkey = null_hash_setkey,
.init = null_init,
.update = null_update,
.finup = null_digest,
.digest = null_digest,
.final = null_final,
.base = {
.cra_name = "digest_null",
.cra_driver_name = "digest_null-generic",
.cra_blocksize = NULL_BLOCK_SIZE,
.cra_module = THIS_MODULE,
}
};
static struct skcipher_alg skcipher_null = {
.base.cra_name = "ecb(cipher_null)",
.base.cra_driver_name = "ecb-cipher_null",
.base.cra_priority = 100,
.base.cra_blocksize = NULL_BLOCK_SIZE,
.base.cra_ctxsize = 0,
.base.cra_module = THIS_MODULE,
.min_keysize = NULL_KEY_SIZE,
.max_keysize = NULL_KEY_SIZE,
.ivsize = NULL_IV_SIZE,
.setkey = null_skcipher_setkey,
.encrypt = null_skcipher_crypt,
.decrypt = null_skcipher_crypt,
};
static struct crypto_alg null_algs[] = { {
.cra_name = "cipher_null",
.cra_driver_name = "cipher_null-generic",
.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
.cra_blocksize = NULL_BLOCK_SIZE,
.cra_ctxsize = 0,
.cra_module = THIS_MODULE,
.cra_u = { .cipher = {
.cia_min_keysize = NULL_KEY_SIZE,
.cia_max_keysize = NULL_KEY_SIZE,
.cia_setkey = null_setkey,
.cia_encrypt = null_crypt,
.cia_decrypt = null_crypt } }
}, {
.cra_name = "compress_null",
.cra_driver_name = "compress_null-generic",
.cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
.cra_blocksize = NULL_BLOCK_SIZE,
.cra_ctxsize = 0,
.cra_module = THIS_MODULE,
.cra_u = { .compress = {
.coa_compress = null_compress,
.coa_decompress = null_compress } }
} };
MODULE_ALIAS_CRYPTO("compress_null");
MODULE_ALIAS_CRYPTO("digest_null");
MODULE_ALIAS_CRYPTO("cipher_null");
struct crypto_sync_skcipher *crypto_get_default_null_skcipher(void)
{
struct crypto_sync_skcipher *tfm;
mutex_lock(&crypto_default_null_skcipher_lock);
tfm = crypto_default_null_skcipher;
if (!tfm) {
tfm = crypto_alloc_sync_skcipher("ecb(cipher_null)", 0, 0);
if (IS_ERR(tfm))
goto unlock;
crypto_default_null_skcipher = tfm;
}
crypto_default_null_skcipher_refcnt++;
unlock:
mutex_unlock(&crypto_default_null_skcipher_lock);
return tfm;
}
EXPORT_SYMBOL_GPL(crypto_get_default_null_skcipher);
void crypto_put_default_null_skcipher(void)
{
mutex_lock(&crypto_default_null_skcipher_lock);
if (!--crypto_default_null_skcipher_refcnt) {
crypto_free_sync_skcipher(crypto_default_null_skcipher);
crypto_default_null_skcipher = NULL;
}
mutex_unlock(&crypto_default_null_skcipher_lock);
}
EXPORT_SYMBOL_GPL(crypto_put_default_null_skcipher);
static int __init crypto_null_mod_init(void)
{
int ret = 0;
ret = crypto_register_algs(null_algs, ARRAY_SIZE(null_algs));
if (ret < 0)
goto out;
ret = crypto_register_shash(&digest_null);
if (ret < 0)
goto out_unregister_algs;
ret = crypto_register_skcipher(&skcipher_null);
if (ret < 0)
goto out_unregister_shash;
return 0;
out_unregister_shash:
crypto_unregister_shash(&digest_null);
out_unregister_algs:
crypto_unregister_algs(null_algs, ARRAY_SIZE(null_algs));
out:
return ret;
}
static void __exit crypto_null_mod_fini(void)
{
crypto_unregister_algs(null_algs, ARRAY_SIZE(null_algs));
crypto_unregister_shash(&digest_null);
crypto_unregister_skcipher(&skcipher_null);
}
subsys_initcall(crypto_null_mod_init);
module_exit(crypto_null_mod_fini);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Null Cryptographic Algorithms");
|
