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git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/blob - crypto/api.c
2 * Scatterlist Cryptographic API.
4 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
5 * Copyright (c) 2002 David S. Miller (davem@redhat.com)
6 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
8 * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
9 * and Nettle, by Niels Möller.
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the Free
13 * Software Foundation; either version 2 of the License, or (at your option)
18 #include <linux/err.h>
19 #include <linux/errno.h>
20 #include <linux/kernel.h>
21 #include <linux/kmod.h>
22 #include <linux/module.h>
23 #include <linux/param.h>
24 #include <linux/sched/signal.h>
25 #include <linux/slab.h>
26 #include <linux/string.h>
27 #include <linux/completion.h>
30 LIST_HEAD(crypto_alg_list
);
31 EXPORT_SYMBOL_GPL(crypto_alg_list
);
32 DECLARE_RWSEM(crypto_alg_sem
);
33 EXPORT_SYMBOL_GPL(crypto_alg_sem
);
35 BLOCKING_NOTIFIER_HEAD(crypto_chain
);
36 EXPORT_SYMBOL_GPL(crypto_chain
);
38 static struct crypto_alg
*crypto_larval_wait(struct crypto_alg
*alg
);
40 struct crypto_alg
*crypto_mod_get(struct crypto_alg
*alg
)
42 return try_module_get(alg
->cra_module
) ? crypto_alg_get(alg
) : NULL
;
44 EXPORT_SYMBOL_GPL(crypto_mod_get
);
46 void crypto_mod_put(struct crypto_alg
*alg
)
48 struct module
*module
= alg
->cra_module
;
53 EXPORT_SYMBOL_GPL(crypto_mod_put
);
55 static inline int crypto_is_test_larval(struct crypto_larval
*larval
)
57 return larval
->alg
.cra_driver_name
[0];
60 static struct crypto_alg
*__crypto_alg_lookup(const char *name
, u32 type
,
63 struct crypto_alg
*q
, *alg
= NULL
;
66 list_for_each_entry(q
, &crypto_alg_list
, cra_list
) {
69 if (crypto_is_moribund(q
))
72 if ((q
->cra_flags
^ type
) & mask
)
75 if (crypto_is_larval(q
) &&
76 !crypto_is_test_larval((struct crypto_larval
*)q
) &&
77 ((struct crypto_larval
*)q
)->mask
!= mask
)
80 exact
= !strcmp(q
->cra_driver_name
, name
);
81 fuzzy
= !strcmp(q
->cra_name
, name
);
82 if (!exact
&& !(fuzzy
&& q
->cra_priority
> best
))
85 if (unlikely(!crypto_mod_get(q
)))
88 best
= q
->cra_priority
;
100 static void crypto_larval_destroy(struct crypto_alg
*alg
)
102 struct crypto_larval
*larval
= (void *)alg
;
104 BUG_ON(!crypto_is_larval(alg
));
106 crypto_mod_put(larval
->adult
);
110 struct crypto_larval
*crypto_larval_alloc(const char *name
, u32 type
, u32 mask
)
112 struct crypto_larval
*larval
;
114 larval
= kzalloc(sizeof(*larval
), GFP_KERNEL
);
116 return ERR_PTR(-ENOMEM
);
119 larval
->alg
.cra_flags
= CRYPTO_ALG_LARVAL
| type
;
120 larval
->alg
.cra_priority
= -1;
121 larval
->alg
.cra_destroy
= crypto_larval_destroy
;
123 strlcpy(larval
->alg
.cra_name
, name
, CRYPTO_MAX_ALG_NAME
);
124 init_completion(&larval
->completion
);
128 EXPORT_SYMBOL_GPL(crypto_larval_alloc
);
130 static struct crypto_alg
*crypto_larval_add(const char *name
, u32 type
,
133 struct crypto_alg
*alg
;
134 struct crypto_larval
*larval
;
136 larval
= crypto_larval_alloc(name
, type
, mask
);
138 return ERR_CAST(larval
);
140 refcount_set(&larval
->alg
.cra_refcnt
, 2);
142 down_write(&crypto_alg_sem
);
143 alg
= __crypto_alg_lookup(name
, type
, mask
);
146 list_add(&alg
->cra_list
, &crypto_alg_list
);
148 up_write(&crypto_alg_sem
);
150 if (alg
!= &larval
->alg
) {
152 if (crypto_is_larval(alg
))
153 alg
= crypto_larval_wait(alg
);
159 void crypto_larval_kill(struct crypto_alg
*alg
)
161 struct crypto_larval
*larval
= (void *)alg
;
163 down_write(&crypto_alg_sem
);
164 list_del(&alg
->cra_list
);
165 up_write(&crypto_alg_sem
);
166 complete_all(&larval
->completion
);
169 EXPORT_SYMBOL_GPL(crypto_larval_kill
);
171 static struct crypto_alg
*crypto_larval_wait(struct crypto_alg
*alg
)
173 struct crypto_larval
*larval
= (void *)alg
;
176 timeout
= wait_for_completion_killable_timeout(
177 &larval
->completion
, 60 * HZ
);
181 alg
= ERR_PTR(-EINTR
);
183 alg
= ERR_PTR(-ETIMEDOUT
);
185 alg
= ERR_PTR(-ENOENT
);
186 else if (crypto_is_test_larval(larval
) &&
187 !(alg
->cra_flags
& CRYPTO_ALG_TESTED
))
188 alg
= ERR_PTR(-EAGAIN
);
189 else if (!crypto_mod_get(alg
))
190 alg
= ERR_PTR(-EAGAIN
);
191 crypto_mod_put(&larval
->alg
);
196 static struct crypto_alg
*crypto_alg_lookup(const char *name
, u32 type
,
199 struct crypto_alg
*alg
;
202 if (!((type
| mask
) & CRYPTO_ALG_TESTED
))
203 test
|= CRYPTO_ALG_TESTED
;
205 down_read(&crypto_alg_sem
);
206 alg
= __crypto_alg_lookup(name
, type
| test
, mask
| test
);
208 alg
= __crypto_alg_lookup(name
, type
, mask
);
209 if (alg
&& !crypto_is_larval(alg
)) {
212 alg
= ERR_PTR(-ELIBBAD
);
215 up_read(&crypto_alg_sem
);
220 static struct crypto_alg
*crypto_larval_lookup(const char *name
, u32 type
,
223 struct crypto_alg
*alg
;
226 return ERR_PTR(-ENOENT
);
228 type
&= ~(CRYPTO_ALG_LARVAL
| CRYPTO_ALG_DEAD
);
229 mask
&= ~(CRYPTO_ALG_LARVAL
| CRYPTO_ALG_DEAD
);
231 alg
= crypto_alg_lookup(name
, type
, mask
);
233 request_module("crypto-%s", name
);
235 if (!((type
^ CRYPTO_ALG_NEED_FALLBACK
) & mask
&
236 CRYPTO_ALG_NEED_FALLBACK
))
237 request_module("crypto-%s-all", name
);
239 alg
= crypto_alg_lookup(name
, type
, mask
);
242 if (!IS_ERR_OR_NULL(alg
) && crypto_is_larval(alg
))
243 alg
= crypto_larval_wait(alg
);
245 alg
= crypto_larval_add(name
, type
, mask
);
250 int crypto_probing_notify(unsigned long val
, void *v
)
254 ok
= blocking_notifier_call_chain(&crypto_chain
, val
, v
);
255 if (ok
== NOTIFY_DONE
) {
256 request_module("cryptomgr");
257 ok
= blocking_notifier_call_chain(&crypto_chain
, val
, v
);
262 EXPORT_SYMBOL_GPL(crypto_probing_notify
);
264 struct crypto_alg
*crypto_alg_mod_lookup(const char *name
, u32 type
, u32 mask
)
266 struct crypto_alg
*alg
;
267 struct crypto_alg
*larval
;
271 * If the internal flag is set for a cipher, require a caller to
272 * to invoke the cipher with the internal flag to use that cipher.
273 * Also, if a caller wants to allocate a cipher that may or may
274 * not be an internal cipher, use type | CRYPTO_ALG_INTERNAL and
275 * !(mask & CRYPTO_ALG_INTERNAL).
277 if (!((type
| mask
) & CRYPTO_ALG_INTERNAL
))
278 mask
|= CRYPTO_ALG_INTERNAL
;
280 larval
= crypto_larval_lookup(name
, type
, mask
);
281 if (IS_ERR(larval
) || !crypto_is_larval(larval
))
284 ok
= crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST
, larval
);
286 if (ok
== NOTIFY_STOP
)
287 alg
= crypto_larval_wait(larval
);
289 crypto_mod_put(larval
);
290 alg
= ERR_PTR(-ENOENT
);
292 crypto_larval_kill(larval
);
295 EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup
);
297 static int crypto_init_ops(struct crypto_tfm
*tfm
, u32 type
, u32 mask
)
299 const struct crypto_type
*type_obj
= tfm
->__crt_alg
->cra_type
;
302 return type_obj
->init(tfm
, type
, mask
);
304 switch (crypto_tfm_alg_type(tfm
)) {
305 case CRYPTO_ALG_TYPE_CIPHER
:
306 return crypto_init_cipher_ops(tfm
);
308 case CRYPTO_ALG_TYPE_COMPRESS
:
309 return crypto_init_compress_ops(tfm
);
319 static void crypto_exit_ops(struct crypto_tfm
*tfm
)
321 const struct crypto_type
*type
= tfm
->__crt_alg
->cra_type
;
323 if (type
&& tfm
->exit
)
327 static unsigned int crypto_ctxsize(struct crypto_alg
*alg
, u32 type
, u32 mask
)
329 const struct crypto_type
*type_obj
= alg
->cra_type
;
332 len
= alg
->cra_alignmask
& ~(crypto_tfm_ctx_alignment() - 1);
334 return len
+ type_obj
->ctxsize(alg
, type
, mask
);
336 switch (alg
->cra_flags
& CRYPTO_ALG_TYPE_MASK
) {
340 case CRYPTO_ALG_TYPE_CIPHER
:
341 len
+= crypto_cipher_ctxsize(alg
);
344 case CRYPTO_ALG_TYPE_COMPRESS
:
345 len
+= crypto_compress_ctxsize(alg
);
352 void crypto_shoot_alg(struct crypto_alg
*alg
)
354 down_write(&crypto_alg_sem
);
355 alg
->cra_flags
|= CRYPTO_ALG_DYING
;
356 up_write(&crypto_alg_sem
);
358 EXPORT_SYMBOL_GPL(crypto_shoot_alg
);
360 struct crypto_tfm
*__crypto_alloc_tfm(struct crypto_alg
*alg
, u32 type
,
363 struct crypto_tfm
*tfm
= NULL
;
364 unsigned int tfm_size
;
367 tfm_size
= sizeof(*tfm
) + crypto_ctxsize(alg
, type
, mask
);
368 tfm
= kzalloc(tfm_size
, GFP_KERNEL
);
372 tfm
->__crt_alg
= alg
;
374 err
= crypto_init_ops(tfm
, type
, mask
);
378 if (!tfm
->exit
&& alg
->cra_init
&& (err
= alg
->cra_init(tfm
)))
379 goto cra_init_failed
;
384 crypto_exit_ops(tfm
);
387 crypto_shoot_alg(alg
);
394 EXPORT_SYMBOL_GPL(__crypto_alloc_tfm
);
397 * crypto_alloc_base - Locate algorithm and allocate transform
398 * @alg_name: Name of algorithm
399 * @type: Type of algorithm
400 * @mask: Mask for type comparison
402 * This function should not be used by new algorithm types.
403 * Please use crypto_alloc_tfm instead.
405 * crypto_alloc_base() will first attempt to locate an already loaded
406 * algorithm. If that fails and the kernel supports dynamically loadable
407 * modules, it will then attempt to load a module of the same name or
408 * alias. If that fails it will send a query to any loaded crypto manager
409 * to construct an algorithm on the fly. A refcount is grabbed on the
410 * algorithm which is then associated with the new transform.
412 * The returned transform is of a non-determinate type. Most people
413 * should use one of the more specific allocation functions such as
414 * crypto_alloc_blkcipher.
416 * In case of error the return value is an error pointer.
418 struct crypto_tfm
*crypto_alloc_base(const char *alg_name
, u32 type
, u32 mask
)
420 struct crypto_tfm
*tfm
;
424 struct crypto_alg
*alg
;
426 alg
= crypto_alg_mod_lookup(alg_name
, type
, mask
);
432 tfm
= __crypto_alloc_tfm(alg
, type
, mask
);
442 if (fatal_signal_pending(current
)) {
450 EXPORT_SYMBOL_GPL(crypto_alloc_base
);
452 void *crypto_create_tfm(struct crypto_alg
*alg
,
453 const struct crypto_type
*frontend
)
456 struct crypto_tfm
*tfm
= NULL
;
457 unsigned int tfmsize
;
461 tfmsize
= frontend
->tfmsize
;
462 total
= tfmsize
+ sizeof(*tfm
) + frontend
->extsize(alg
);
464 mem
= kzalloc(total
, GFP_KERNEL
);
468 tfm
= (struct crypto_tfm
*)(mem
+ tfmsize
);
469 tfm
->__crt_alg
= alg
;
471 err
= frontend
->init_tfm(tfm
);
475 if (!tfm
->exit
&& alg
->cra_init
&& (err
= alg
->cra_init(tfm
)))
476 goto cra_init_failed
;
481 crypto_exit_ops(tfm
);
484 crypto_shoot_alg(alg
);
491 EXPORT_SYMBOL_GPL(crypto_create_tfm
);
493 struct crypto_alg
*crypto_find_alg(const char *alg_name
,
494 const struct crypto_type
*frontend
,
498 type
&= frontend
->maskclear
;
499 mask
&= frontend
->maskclear
;
500 type
|= frontend
->type
;
501 mask
|= frontend
->maskset
;
504 return crypto_alg_mod_lookup(alg_name
, type
, mask
);
506 EXPORT_SYMBOL_GPL(crypto_find_alg
);
509 * crypto_alloc_tfm - Locate algorithm and allocate transform
510 * @alg_name: Name of algorithm
511 * @frontend: Frontend algorithm type
512 * @type: Type of algorithm
513 * @mask: Mask for type comparison
515 * crypto_alloc_tfm() will first attempt to locate an already loaded
516 * algorithm. If that fails and the kernel supports dynamically loadable
517 * modules, it will then attempt to load a module of the same name or
518 * alias. If that fails it will send a query to any loaded crypto manager
519 * to construct an algorithm on the fly. A refcount is grabbed on the
520 * algorithm which is then associated with the new transform.
522 * The returned transform is of a non-determinate type. Most people
523 * should use one of the more specific allocation functions such as
524 * crypto_alloc_blkcipher.
526 * In case of error the return value is an error pointer.
528 void *crypto_alloc_tfm(const char *alg_name
,
529 const struct crypto_type
*frontend
, u32 type
, u32 mask
)
535 struct crypto_alg
*alg
;
537 alg
= crypto_find_alg(alg_name
, frontend
, type
, mask
);
543 tfm
= crypto_create_tfm(alg
, frontend
);
553 if (fatal_signal_pending(current
)) {
561 EXPORT_SYMBOL_GPL(crypto_alloc_tfm
);
564 * crypto_destroy_tfm - Free crypto transform
565 * @mem: Start of tfm slab
566 * @tfm: Transform to free
568 * This function frees up the transform and any associated resources,
569 * then drops the refcount on the associated algorithm.
571 void crypto_destroy_tfm(void *mem
, struct crypto_tfm
*tfm
)
573 struct crypto_alg
*alg
;
578 alg
= tfm
->__crt_alg
;
580 if (!tfm
->exit
&& alg
->cra_exit
)
582 crypto_exit_ops(tfm
);
586 EXPORT_SYMBOL_GPL(crypto_destroy_tfm
);
588 int crypto_has_alg(const char *name
, u32 type
, u32 mask
)
591 struct crypto_alg
*alg
= crypto_alg_mod_lookup(name
, type
, mask
);
600 EXPORT_SYMBOL_GPL(crypto_has_alg
);
602 void crypto_req_done(struct crypto_async_request
*req
, int err
)
604 struct crypto_wait
*wait
= req
->data
;
606 if (err
== -EINPROGRESS
)
610 complete(&wait
->completion
);
612 EXPORT_SYMBOL_GPL(crypto_req_done
);
614 MODULE_DESCRIPTION("Cryptographic core API");
615 MODULE_LICENSE("GPL");