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
226
227
228
229
230
231
232
233
|
/*
* Scatterlist Cryptographic API.
*
* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
* Copyright (c) 2002 David S. Miller (davem@redhat.com)
*
* Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
* and Nettle, by Niels Möller.
*
* 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/crypto.h>
#include <linux/errno.h>
#include <linux/rwsem.h>
#include <linux/slab.h>
#include "internal.h"
LIST_HEAD(crypto_alg_list);
DECLARE_RWSEM(crypto_alg_sem);
static inline int crypto_alg_get(struct crypto_alg *alg)
{
return try_module_get(alg->cra_module);
}
static inline void crypto_alg_put(struct crypto_alg *alg)
{
module_put(alg->cra_module);
}
struct crypto_alg *crypto_alg_lookup(const char *name)
{
struct crypto_alg *q, *alg = NULL;
if (!name)
return NULL;
down_read(&crypto_alg_sem);
list_for_each_entry(q, &crypto_alg_list, cra_list) {
if (!(strcmp(q->cra_name, name))) {
if (crypto_alg_get(q))
alg = q;
break;
}
}
up_read(&crypto_alg_sem);
return alg;
}
static int crypto_init_flags(struct crypto_tfm *tfm, u32 flags)
{
tfm->crt_flags = 0;
switch (crypto_tfm_alg_type(tfm)) {
case CRYPTO_ALG_TYPE_CIPHER:
return crypto_init_cipher_flags(tfm, flags);
case CRYPTO_ALG_TYPE_DIGEST:
return crypto_init_digest_flags(tfm, flags);
case CRYPTO_ALG_TYPE_COMPRESS:
return crypto_init_compress_flags(tfm, flags);
default:
break;
}
BUG();
return -EINVAL;
}
static int crypto_init_ops(struct crypto_tfm *tfm)
{
switch (crypto_tfm_alg_type(tfm)) {
case CRYPTO_ALG_TYPE_CIPHER:
return crypto_init_cipher_ops(tfm);
case CRYPTO_ALG_TYPE_DIGEST:
return crypto_init_digest_ops(tfm);
case CRYPTO_ALG_TYPE_COMPRESS:
return crypto_init_compress_ops(tfm);
default:
break;
}
BUG();
return -EINVAL;
}
static void crypto_exit_ops(struct crypto_tfm *tfm)
{
switch (crypto_tfm_alg_type(tfm)) {
case CRYPTO_ALG_TYPE_CIPHER:
crypto_exit_cipher_ops(tfm);
break;
case CRYPTO_ALG_TYPE_DIGEST:
crypto_exit_digest_ops(tfm);
break;
case CRYPTO_ALG_TYPE_COMPRESS:
crypto_exit_compress_ops(tfm);
break;
default:
BUG();
}
}
struct crypto_tfm *crypto_alloc_tfm(const char *name, u32 flags)
{
struct crypto_tfm *tfm = NULL;
struct crypto_alg *alg;
alg = crypto_alg_mod_lookup(name);
if (alg == NULL)
goto out;
tfm = kmalloc(sizeof(*tfm) + alg->cra_ctxsize, GFP_KERNEL);
if (tfm == NULL)
goto out_put;
memset(tfm, 0, sizeof(*tfm) + alg->cra_ctxsize);
tfm->__crt_alg = alg;
if (crypto_init_flags(tfm, flags))
goto out_free_tfm;
if (crypto_init_ops(tfm)) {
crypto_exit_ops(tfm);
goto out_free_tfm;
}
goto out;
out_free_tfm:
kfree(tfm);
tfm = NULL;
out_put:
crypto_alg_put(alg);
out:
return tfm;
}
void crypto_free_tfm(struct crypto_tfm *tfm)
{
struct crypto_alg *alg = tfm->__crt_alg;
int size = sizeof(*tfm) + alg->cra_ctxsize;
crypto_exit_ops(tfm);
crypto_alg_put(alg);
memset(tfm, 0, size);
kfree(tfm);
}
int crypto_register_alg(struct crypto_alg *alg)
{
int ret = 0;
struct crypto_alg *q;
down_write(&crypto_alg_sem);
list_for_each_entry(q, &crypto_alg_list, cra_list) {
if (!(strcmp(q->cra_name, alg->cra_name))) {
ret = -EEXIST;
goto out;
}
}
list_add_tail(&alg->cra_list, &crypto_alg_list);
out:
up_write(&crypto_alg_sem);
return ret;
}
int crypto_unregister_alg(struct crypto_alg *alg)
{
int ret = -ENOENT;
struct crypto_alg *q;
BUG_ON(!alg->cra_module);
down_write(&crypto_alg_sem);
list_for_each_entry(q, &crypto_alg_list, cra_list) {
if (alg == q) {
list_del(&alg->cra_list);
ret = 0;
goto out;
}
}
out:
up_write(&crypto_alg_sem);
return ret;
}
int crypto_alg_available(const char *name, u32 flags)
{
int ret = 0;
struct crypto_alg *alg = crypto_alg_mod_lookup(name);
if (alg) {
crypto_alg_put(alg);
ret = 1;
}
return ret;
}
static int __init init_crypto(void)
{
printk(KERN_INFO "Initializing Cryptographic API\n");
crypto_init_proc();
return 0;
}
__initcall(init_crypto);
EXPORT_SYMBOL_GPL(crypto_register_alg);
EXPORT_SYMBOL_GPL(crypto_unregister_alg);
EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
EXPORT_SYMBOL_GPL(crypto_free_tfm);
EXPORT_SYMBOL_GPL(crypto_alg_available);
|
