2 * Scatterlist Cryptographic API.
4 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
5 * Copyright (c) 2002 David S. Miller (davem@redhat.com)
7 * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
8 * and Nettle, by Niels Möller.
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the Free
12 * Software Foundation; either version 2 of the License, or (at your option)
16 #include <linux/init.h>
17 #include <linux/crypto.h>
18 #include <linux/errno.h>
19 #include <linux/rwsem.h>
20 #include <linux/slab.h>
23 LIST_HEAD(crypto_alg_list
);
24 DECLARE_RWSEM(crypto_alg_sem
);
26 static inline int crypto_alg_get(struct crypto_alg
*alg
)
28 return try_module_get(alg
->cra_module
);
31 static inline void crypto_alg_put(struct crypto_alg
*alg
)
33 module_put(alg
->cra_module
);
36 struct crypto_alg
*crypto_alg_lookup(const char *name
)
38 struct crypto_alg
*q
, *alg
= NULL
;
43 down_read(&crypto_alg_sem
);
45 list_for_each_entry(q
, &crypto_alg_list
, cra_list
) {
46 if (!(strcmp(q
->cra_name
, name
))) {
47 if (crypto_alg_get(q
))
53 up_read(&crypto_alg_sem
);
57 static int crypto_init_flags(struct crypto_tfm
*tfm
, u32 flags
)
61 switch (crypto_tfm_alg_type(tfm
)) {
62 case CRYPTO_ALG_TYPE_CIPHER
:
63 return crypto_init_cipher_flags(tfm
, flags
);
65 case CRYPTO_ALG_TYPE_DIGEST
:
66 return crypto_init_digest_flags(tfm
, flags
);
68 case CRYPTO_ALG_TYPE_COMPRESS
:
69 return crypto_init_compress_flags(tfm
, flags
);
79 static int crypto_init_ops(struct crypto_tfm
*tfm
)
81 switch (crypto_tfm_alg_type(tfm
)) {
82 case CRYPTO_ALG_TYPE_CIPHER
:
83 return crypto_init_cipher_ops(tfm
);
85 case CRYPTO_ALG_TYPE_DIGEST
:
86 return crypto_init_digest_ops(tfm
);
88 case CRYPTO_ALG_TYPE_COMPRESS
:
89 return crypto_init_compress_ops(tfm
);
99 static void crypto_exit_ops(struct crypto_tfm
*tfm
)
101 switch (crypto_tfm_alg_type(tfm
)) {
102 case CRYPTO_ALG_TYPE_CIPHER
:
103 crypto_exit_cipher_ops(tfm
);
106 case CRYPTO_ALG_TYPE_DIGEST
:
107 crypto_exit_digest_ops(tfm
);
110 case CRYPTO_ALG_TYPE_COMPRESS
:
111 crypto_exit_compress_ops(tfm
);
120 struct crypto_tfm
*crypto_alloc_tfm(const char *name
, u32 flags
)
122 struct crypto_tfm
*tfm
= NULL
;
123 struct crypto_alg
*alg
;
125 alg
= crypto_alg_mod_lookup(name
);
129 tfm
= kmalloc(sizeof(*tfm
) + alg
->cra_ctxsize
, GFP_KERNEL
);
133 memset(tfm
, 0, sizeof(*tfm
) + alg
->cra_ctxsize
);
135 tfm
->__crt_alg
= alg
;
137 if (crypto_init_flags(tfm
, flags
))
140 if (crypto_init_ops(tfm
)) {
141 crypto_exit_ops(tfm
);
156 void crypto_free_tfm(struct crypto_tfm
*tfm
)
158 struct crypto_alg
*alg
= tfm
->__crt_alg
;
159 int size
= sizeof(*tfm
) + alg
->cra_ctxsize
;
161 crypto_exit_ops(tfm
);
163 memset(tfm
, 0, size
);
167 int crypto_register_alg(struct crypto_alg
*alg
)
170 struct crypto_alg
*q
;
172 if (alg
->cra_alignmask
& (alg
->cra_alignmask
+ 1))
175 if (alg
->cra_alignmask
> PAGE_SIZE
)
178 down_write(&crypto_alg_sem
);
180 list_for_each_entry(q
, &crypto_alg_list
, cra_list
) {
181 if (!(strcmp(q
->cra_name
, alg
->cra_name
))) {
187 list_add_tail(&alg
->cra_list
, &crypto_alg_list
);
189 up_write(&crypto_alg_sem
);
193 int crypto_unregister_alg(struct crypto_alg
*alg
)
196 struct crypto_alg
*q
;
198 BUG_ON(!alg
->cra_module
);
200 down_write(&crypto_alg_sem
);
201 list_for_each_entry(q
, &crypto_alg_list
, cra_list
) {
203 list_del(&alg
->cra_list
);
209 up_write(&crypto_alg_sem
);
213 int crypto_alg_available(const char *name
, u32 flags
)
216 struct crypto_alg
*alg
= crypto_alg_mod_lookup(name
);
226 static int __init
init_crypto(void)
228 printk(KERN_INFO
"Initializing Cryptographic API\n");
233 __initcall(init_crypto
);
235 EXPORT_SYMBOL_GPL(crypto_register_alg
);
236 EXPORT_SYMBOL_GPL(crypto_unregister_alg
);
237 EXPORT_SYMBOL_GPL(crypto_alloc_tfm
);
238 EXPORT_SYMBOL_GPL(crypto_free_tfm
);
239 EXPORT_SYMBOL_GPL(crypto_alg_available
);