xref: /linux/crypto/api.c (revision 25489a4f556414445d342951615178368ee45cde) 
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Scatterlist Cryptographic API.
4  *
5  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
6  * Copyright (c) 2002 David S. Miller (davem@redhat.com)
7  * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
8  *
9  * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
10  * and Nettle, by Niels Möller.
11  */
12 
13 #include <linux/err.h>
14 #include <linux/errno.h>
15 #include <linux/jump_label.h>
16 #include <linux/kernel.h>
17 #include <linux/kmod.h>
18 #include <linux/module.h>
19 #include <linux/param.h>
20 #include <linux/sched/signal.h>
21 #include <linux/slab.h>
22 #include <linux/string.h>
23 #include <linux/completion.h>
24 #include "internal.h"
25 
26 LIST_HEAD(crypto_alg_list);
27 EXPORT_SYMBOL_GPL(crypto_alg_list);
28 DECLARE_RWSEM(crypto_alg_sem);
29 EXPORT_SYMBOL_GPL(crypto_alg_sem);
30 
31 BLOCKING_NOTIFIER_HEAD(crypto_chain);
32 EXPORT_SYMBOL_GPL(crypto_chain);
33 
34 #if IS_BUILTIN(CONFIG_CRYPTO_ALGAPI) && IS_ENABLED(CONFIG_CRYPTO_SELFTESTS)
35 DEFINE_STATIC_KEY_FALSE(__crypto_boot_test_finished);
36 #endif
37 
38 static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg,
39 					     u32 type, u32 mask);
40 static struct crypto_alg *crypto_alg_lookup(const char *name, u32 type,
41 					    u32 mask);
42 
43 struct crypto_alg *crypto_mod_get(struct crypto_alg *alg)
44 {
45 	return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
46 }
47 EXPORT_SYMBOL_GPL(crypto_mod_get);
48 
49 void crypto_mod_put(struct crypto_alg *alg)
50 {
51 	struct module *module = alg->cra_module;
52 
53 	crypto_alg_put(alg);
54 	module_put(module);
55 }
56 EXPORT_SYMBOL_GPL(crypto_mod_put);
57 
58 static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
59 					      u32 mask)
60 {
61 	struct crypto_alg *q, *alg = NULL;
62 	int best = -2;
63 
64 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
65 		int exact, fuzzy;
66 
67 		if (crypto_is_moribund(q))
68 			continue;
69 
70 		if ((q->cra_flags ^ type) & mask)
71 			continue;
72 
73 		exact = !strcmp(q->cra_driver_name, name);
74 		fuzzy = !strcmp(q->cra_name, name);
75 		if (!exact && !(fuzzy && q->cra_priority > best))
76 			continue;
77 
78 		if (unlikely(!crypto_mod_get(q)))
79 			continue;
80 
81 		best = q->cra_priority;
82 		if (alg)
83 			crypto_mod_put(alg);
84 		alg = q;
85 
86 		if (exact)
87 			break;
88 	}
89 
90 	return alg;
91 }
92 
93 static void crypto_larval_destroy(struct crypto_alg *alg)
94 {
95 	struct crypto_larval *larval = (void *)alg;
96 
97 	BUG_ON(!crypto_is_larval(alg));
98 	if (!IS_ERR_OR_NULL(larval->adult))
99 		crypto_mod_put(larval->adult);
100 	kfree(larval);
101 }
102 
103 struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask)
104 {
105 	struct crypto_larval *larval;
106 
107 	larval = kzalloc(sizeof(*larval), GFP_KERNEL);
108 	if (!larval)
109 		return ERR_PTR(-ENOMEM);
110 
111 	type &= ~CRYPTO_ALG_TYPE_MASK | (mask ?: CRYPTO_ALG_TYPE_MASK);
112 
113 	larval->mask = mask;
114 	larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type;
115 	larval->alg.cra_priority = -1;
116 	larval->alg.cra_destroy = crypto_larval_destroy;
117 
118 	strscpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
119 	init_completion(&larval->completion);
120 
121 	return larval;
122 }
123 EXPORT_SYMBOL_GPL(crypto_larval_alloc);
124 
125 static struct crypto_alg *crypto_larval_add(const char *name, u32 type,
126 					    u32 mask)
127 {
128 	struct crypto_alg *alg;
129 	struct crypto_larval *larval;
130 
131 	larval = crypto_larval_alloc(name, type, mask);
132 	if (IS_ERR(larval))
133 		return ERR_CAST(larval);
134 
135 	refcount_set(&larval->alg.cra_refcnt, 2);
136 
137 	down_write(&crypto_alg_sem);
138 	alg = __crypto_alg_lookup(name, type, mask);
139 	if (!alg) {
140 		alg = &larval->alg;
141 		list_add(&alg->cra_list, &crypto_alg_list);
142 	}
143 	up_write(&crypto_alg_sem);
144 
145 	if (alg != &larval->alg) {
146 		kfree(larval);
147 		if (crypto_is_larval(alg))
148 			alg = crypto_larval_wait(alg, type, mask);
149 	}
150 
151 	return alg;
152 }
153 
154 static void crypto_larval_kill(struct crypto_larval *larval)
155 {
156 	bool unlinked;
157 
158 	down_write(&crypto_alg_sem);
159 	unlinked = list_empty(&larval->alg.cra_list);
160 	if (!unlinked)
161 		list_del_init(&larval->alg.cra_list);
162 	up_write(&crypto_alg_sem);
163 
164 	if (unlinked)
165 		return;
166 
167 	complete_all(&larval->completion);
168 	crypto_alg_put(&larval->alg);
169 }
170 
171 void crypto_schedule_test(struct crypto_larval *larval)
172 {
173 	int err;
174 
175 	err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
176 	WARN_ON_ONCE(err != NOTIFY_STOP);
177 }
178 EXPORT_SYMBOL_GPL(crypto_schedule_test);
179 
180 static void crypto_start_test(struct crypto_larval *larval)
181 {
182 	if (!crypto_is_test_larval(larval))
183 		return;
184 
185 	if (larval->test_started)
186 		return;
187 
188 	down_write(&crypto_alg_sem);
189 	if (larval->test_started) {
190 		up_write(&crypto_alg_sem);
191 		return;
192 	}
193 
194 	larval->test_started = true;
195 	up_write(&crypto_alg_sem);
196 
197 	crypto_schedule_test(larval);
198 }
199 
200 static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg,
201 					     u32 type, u32 mask)
202 {
203 	struct crypto_larval *larval;
204 	long time_left;
205 
206 again:
207 	larval = container_of(alg, struct crypto_larval, alg);
208 
209 	if (!crypto_boot_test_finished())
210 		crypto_start_test(larval);
211 
212 	time_left = wait_for_completion_killable_timeout(
213 		&larval->completion, 60 * HZ);
214 
215 	alg = larval->adult;
216 	if (time_left < 0)
217 		alg = ERR_PTR(-EINTR);
218 	else if (!time_left) {
219 		if (crypto_is_test_larval(larval))
220 			crypto_larval_kill(larval);
221 		alg = ERR_PTR(-ETIMEDOUT);
222 	} else if (!alg || PTR_ERR(alg) == -EEXIST) {
223 		int err = alg ? -EEXIST : -EAGAIN;
224 
225 		/*
226 		 * EEXIST is expected because two probes can be scheduled
227 		 * at the same time with one using alg_name and the other
228 		 * using driver_name.  Do a re-lookup but do not retry in
229 		 * case we hit a quirk like gcm_base(ctr(aes),...) which
230 		 * will never match.
231 		 */
232 		alg = &larval->alg;
233 		alg = crypto_alg_lookup(alg->cra_name, type, mask) ?:
234 		      ERR_PTR(err);
235 	} else if (IS_ERR(alg))
236 		;
237 	else if (crypto_is_test_larval(larval) &&
238 		 !(alg->cra_flags & CRYPTO_ALG_TESTED))
239 		alg = ERR_PTR(-EAGAIN);
240 	else if (alg->cra_flags & CRYPTO_ALG_FIPS_INTERNAL)
241 		alg = ERR_PTR(-EAGAIN);
242 	else if (!crypto_mod_get(alg))
243 		alg = ERR_PTR(-EAGAIN);
244 	crypto_mod_put(&larval->alg);
245 
246 	if (!IS_ERR(alg) && crypto_is_larval(alg))
247 		goto again;
248 
249 	return alg;
250 }
251 
252 static struct crypto_alg *crypto_alg_lookup(const char *name, u32 type,
253 					    u32 mask)
254 {
255 	const u32 fips = CRYPTO_ALG_FIPS_INTERNAL;
256 	struct crypto_alg *alg;
257 	u32 test = 0;
258 
259 	if (!((type | mask) & CRYPTO_ALG_TESTED))
260 		test |= CRYPTO_ALG_TESTED;
261 
262 	down_read(&crypto_alg_sem);
263 	alg = __crypto_alg_lookup(name, (type | test) & ~fips,
264 				  (mask | test) & ~fips);
265 	if (alg) {
266 		if (((type | mask) ^ fips) & fips)
267 			mask |= fips;
268 		mask &= fips;
269 
270 		if (!crypto_is_larval(alg) &&
271 		    ((type ^ alg->cra_flags) & mask)) {
272 			/* Algorithm is disallowed in FIPS mode. */
273 			crypto_mod_put(alg);
274 			alg = ERR_PTR(-ENOENT);
275 		}
276 	} else if (test) {
277 		alg = __crypto_alg_lookup(name, type, mask);
278 		if (alg && !crypto_is_larval(alg)) {
279 			/* Test failed */
280 			crypto_mod_put(alg);
281 			alg = ERR_PTR(-ELIBBAD);
282 		}
283 	}
284 	up_read(&crypto_alg_sem);
285 
286 	return alg;
287 }
288 
289 static struct crypto_alg *crypto_larval_lookup(const char *name, u32 type,
290 					       u32 mask)
291 {
292 	struct crypto_alg *alg;
293 
294 	if (!name)
295 		return ERR_PTR(-ENOENT);
296 
297 	type &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
298 	mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
299 
300 	alg = crypto_alg_lookup(name, type, mask);
301 	if (!alg && !(mask & CRYPTO_NOLOAD)) {
302 		request_module("crypto-%s", name);
303 
304 		if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
305 		      CRYPTO_ALG_NEED_FALLBACK))
306 			request_module("crypto-%s-all", name);
307 
308 		alg = crypto_alg_lookup(name, type, mask);
309 	}
310 
311 	if (!IS_ERR_OR_NULL(alg) && crypto_is_larval(alg))
312 		alg = crypto_larval_wait(alg, type, mask);
313 	else if (alg)
314 		;
315 	else if (!(mask & CRYPTO_ALG_TESTED))
316 		alg = crypto_larval_add(name, type, mask);
317 	else
318 		alg = ERR_PTR(-ENOENT);
319 
320 	return alg;
321 }
322 
323 int crypto_probing_notify(unsigned long val, void *v)
324 {
325 	int ok;
326 
327 	ok = blocking_notifier_call_chain(&crypto_chain, val, v);
328 	if (ok == NOTIFY_DONE) {
329 		request_module("cryptomgr");
330 		ok = blocking_notifier_call_chain(&crypto_chain, val, v);
331 	}
332 
333 	return ok;
334 }
335 EXPORT_SYMBOL_GPL(crypto_probing_notify);
336 
337 struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
338 {
339 	struct crypto_alg *alg;
340 	struct crypto_alg *larval;
341 	int ok;
342 
343 	/*
344 	 * If the internal flag is set for a cipher, require a caller to
345 	 * invoke the cipher with the internal flag to use that cipher.
346 	 * Also, if a caller wants to allocate a cipher that may or may
347 	 * not be an internal cipher, use type | CRYPTO_ALG_INTERNAL and
348 	 * !(mask & CRYPTO_ALG_INTERNAL).
349 	 */
350 	if (!((type | mask) & CRYPTO_ALG_INTERNAL))
351 		mask |= CRYPTO_ALG_INTERNAL;
352 
353 	larval = crypto_larval_lookup(name, type, mask);
354 	if (IS_ERR(larval) || !crypto_is_larval(larval))
355 		return larval;
356 
357 	ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
358 
359 	if (ok == NOTIFY_STOP)
360 		alg = crypto_larval_wait(larval, type, mask);
361 	else {
362 		crypto_mod_put(larval);
363 		alg = ERR_PTR(-ENOENT);
364 	}
365 	crypto_larval_kill(container_of(larval, struct crypto_larval, alg));
366 	return alg;
367 }
368 EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
369 
370 static void crypto_exit_ops(struct crypto_tfm *tfm)
371 {
372 	const struct crypto_type *type = tfm->__crt_alg->cra_type;
373 
374 	if (type && tfm->exit)
375 		tfm->exit(tfm);
376 }
377 
378 static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
379 {
380 	const struct crypto_type *type_obj = alg->cra_type;
381 	unsigned int len;
382 
383 	len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
384 	if (type_obj)
385 		return len + type_obj->ctxsize(alg, type, mask);
386 
387 	switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
388 	default:
389 		BUG();
390 
391 	case CRYPTO_ALG_TYPE_CIPHER:
392 		len += crypto_cipher_ctxsize(alg);
393 		break;
394 	}
395 
396 	return len;
397 }
398 
399 void crypto_shoot_alg(struct crypto_alg *alg)
400 {
401 	down_write(&crypto_alg_sem);
402 	alg->cra_flags |= CRYPTO_ALG_DYING;
403 	up_write(&crypto_alg_sem);
404 }
405 EXPORT_SYMBOL_GPL(crypto_shoot_alg);
406 
407 struct crypto_tfm *__crypto_alloc_tfmgfp(struct crypto_alg *alg, u32 type,
408 					 u32 mask, gfp_t gfp)
409 {
410 	struct crypto_tfm *tfm;
411 	unsigned int tfm_size;
412 	int err = -ENOMEM;
413 
414 	tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
415 	tfm = kzalloc(tfm_size, gfp);
416 	if (tfm == NULL)
417 		goto out_err;
418 
419 	tfm->__crt_alg = alg;
420 	refcount_set(&tfm->refcnt, 1);
421 
422 	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
423 		goto cra_init_failed;
424 
425 	goto out;
426 
427 cra_init_failed:
428 	crypto_exit_ops(tfm);
429 	if (err == -EAGAIN)
430 		crypto_shoot_alg(alg);
431 	kfree(tfm);
432 out_err:
433 	tfm = ERR_PTR(err);
434 out:
435 	return tfm;
436 }
437 EXPORT_SYMBOL_GPL(__crypto_alloc_tfmgfp);
438 
439 struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
440 				      u32 mask)
441 {
442 	return __crypto_alloc_tfmgfp(alg, type, mask, GFP_KERNEL);
443 }
444 EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
445 
446 /*
447  *	crypto_alloc_base - Locate algorithm and allocate transform
448  *	@alg_name: Name of algorithm
449  *	@type: Type of algorithm
450  *	@mask: Mask for type comparison
451  *
452  *	This function should not be used by new algorithm types.
453  *	Please use crypto_alloc_tfm instead.
454  *
455  *	crypto_alloc_base() will first attempt to locate an already loaded
456  *	algorithm.  If that fails and the kernel supports dynamically loadable
457  *	modules, it will then attempt to load a module of the same name or
458  *	alias.  If that fails it will send a query to any loaded crypto manager
459  *	to construct an algorithm on the fly.  A refcount is grabbed on the
460  *	algorithm which is then associated with the new transform.
461  *
462  *	The returned transform is of a non-determinate type.  Most people
463  *	should use one of the more specific allocation functions such as
464  *	crypto_alloc_skcipher().
465  *
466  *	In case of error the return value is an error pointer.
467  */
468 struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
469 {
470 	struct crypto_tfm *tfm;
471 	int err;
472 
473 	for (;;) {
474 		struct crypto_alg *alg;
475 
476 		alg = crypto_alg_mod_lookup(alg_name, type, mask);
477 		if (IS_ERR(alg)) {
478 			err = PTR_ERR(alg);
479 			goto err;
480 		}
481 
482 		tfm = __crypto_alloc_tfm(alg, type, mask);
483 		if (!IS_ERR(tfm))
484 			return tfm;
485 
486 		crypto_mod_put(alg);
487 		err = PTR_ERR(tfm);
488 
489 err:
490 		if (err != -EAGAIN)
491 			break;
492 		if (fatal_signal_pending(current)) {
493 			err = -EINTR;
494 			break;
495 		}
496 	}
497 
498 	return ERR_PTR(err);
499 }
500 EXPORT_SYMBOL_GPL(crypto_alloc_base);
501 
502 static void *crypto_alloc_tfmmem(struct crypto_alg *alg,
503 				 const struct crypto_type *frontend, int node,
504 				 gfp_t gfp)
505 {
506 	struct crypto_tfm *tfm;
507 	unsigned int tfmsize;
508 	unsigned int total;
509 	char *mem;
510 
511 	tfmsize = frontend->tfmsize;
512 	total = tfmsize + sizeof(*tfm) + frontend->extsize(alg);
513 
514 	mem = kzalloc_node(total, gfp, node);
515 	if (mem == NULL)
516 		return ERR_PTR(-ENOMEM);
517 
518 	tfm = (struct crypto_tfm *)(mem + tfmsize);
519 	tfm->__crt_alg = alg;
520 	tfm->node = node;
521 	refcount_set(&tfm->refcnt, 1);
522 
523 	return mem;
524 }
525 
526 void *crypto_create_tfm_node(struct crypto_alg *alg,
527 			     const struct crypto_type *frontend,
528 			     int node)
529 {
530 	struct crypto_tfm *tfm;
531 	char *mem;
532 	int err;
533 
534 	mem = crypto_alloc_tfmmem(alg, frontend, node, GFP_KERNEL);
535 	if (IS_ERR(mem))
536 		goto out;
537 
538 	tfm = (struct crypto_tfm *)(mem + frontend->tfmsize);
539 	tfm->fb = tfm;
540 
541 	err = frontend->init_tfm(tfm);
542 	if (err)
543 		goto out_free_tfm;
544 
545 	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
546 		goto cra_init_failed;
547 
548 	goto out;
549 
550 cra_init_failed:
551 	crypto_exit_ops(tfm);
552 out_free_tfm:
553 	if (err == -EAGAIN)
554 		crypto_shoot_alg(alg);
555 	kfree(mem);
556 	mem = ERR_PTR(err);
557 out:
558 	return mem;
559 }
560 EXPORT_SYMBOL_GPL(crypto_create_tfm_node);
561 
562 void *crypto_clone_tfm(const struct crypto_type *frontend,
563 		       struct crypto_tfm *otfm)
564 {
565 	struct crypto_alg *alg = otfm->__crt_alg;
566 	struct crypto_tfm *tfm;
567 	char *mem;
568 
569 	mem = ERR_PTR(-ESTALE);
570 	if (unlikely(!crypto_mod_get(alg)))
571 		goto out;
572 
573 	mem = crypto_alloc_tfmmem(alg, frontend, otfm->node, GFP_ATOMIC);
574 	if (IS_ERR(mem)) {
575 		crypto_mod_put(alg);
576 		goto out;
577 	}
578 
579 	tfm = (struct crypto_tfm *)(mem + frontend->tfmsize);
580 	tfm->crt_flags = otfm->crt_flags;
581 	tfm->fb = tfm;
582 
583 out:
584 	return mem;
585 }
586 EXPORT_SYMBOL_GPL(crypto_clone_tfm);
587 
588 struct crypto_alg *crypto_find_alg(const char *alg_name,
589 				   const struct crypto_type *frontend,
590 				   u32 type, u32 mask)
591 {
592 	if (frontend) {
593 		type &= frontend->maskclear;
594 		mask &= frontend->maskclear;
595 		type |= frontend->type;
596 		mask |= frontend->maskset;
597 	}
598 
599 	return crypto_alg_mod_lookup(alg_name, type, mask);
600 }
601 EXPORT_SYMBOL_GPL(crypto_find_alg);
602 
603 /*
604  *	crypto_alloc_tfm_node - Locate algorithm and allocate transform
605  *	@alg_name: Name of algorithm
606  *	@frontend: Frontend algorithm type
607  *	@type: Type of algorithm
608  *	@mask: Mask for type comparison
609  *	@node: NUMA node in which users desire to put requests, if node is
610  *		NUMA_NO_NODE, it means users have no special requirement.
611  *
612  *	crypto_alloc_tfm() will first attempt to locate an already loaded
613  *	algorithm.  If that fails and the kernel supports dynamically loadable
614  *	modules, it will then attempt to load a module of the same name or
615  *	alias.  If that fails it will send a query to any loaded crypto manager
616  *	to construct an algorithm on the fly.  A refcount is grabbed on the
617  *	algorithm which is then associated with the new transform.
618  *
619  *	The returned transform is of a non-determinate type.  Most people
620  *	should use one of the more specific allocation functions such as
621  *	crypto_alloc_skcipher().
622  *
623  *	In case of error the return value is an error pointer.
624  */
625 
626 void *crypto_alloc_tfm_node(const char *alg_name,
627 		       const struct crypto_type *frontend, u32 type, u32 mask,
628 		       int node)
629 {
630 	void *tfm;
631 	int err;
632 
633 	for (;;) {
634 		struct crypto_alg *alg;
635 
636 		alg = crypto_find_alg(alg_name, frontend, type, mask);
637 		if (IS_ERR(alg)) {
638 			err = PTR_ERR(alg);
639 			goto err;
640 		}
641 
642 		tfm = crypto_create_tfm_node(alg, frontend, node);
643 		if (!IS_ERR(tfm))
644 			return tfm;
645 
646 		crypto_mod_put(alg);
647 		err = PTR_ERR(tfm);
648 
649 err:
650 		if (err != -EAGAIN)
651 			break;
652 		if (fatal_signal_pending(current)) {
653 			err = -EINTR;
654 			break;
655 		}
656 	}
657 
658 	return ERR_PTR(err);
659 }
660 EXPORT_SYMBOL_GPL(crypto_alloc_tfm_node);
661 
662 /*
663  *	crypto_destroy_tfm - Free crypto transform
664  *	@mem: Start of tfm slab
665  *	@tfm: Transform to free
666  *
667  *	This function frees up the transform and any associated resources,
668  *	then drops the refcount on the associated algorithm.
669  */
670 void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
671 {
672 	struct crypto_alg *alg;
673 
674 	if (IS_ERR_OR_NULL(mem))
675 		return;
676 
677 	if (!refcount_dec_and_test(&tfm->refcnt))
678 		return;
679 	alg = tfm->__crt_alg;
680 
681 	if (!tfm->exit && alg->cra_exit)
682 		alg->cra_exit(tfm);
683 	crypto_exit_ops(tfm);
684 	crypto_mod_put(alg);
685 	kfree_sensitive(mem);
686 }
687 EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
688 
689 int crypto_has_alg(const char *name, u32 type, u32 mask)
690 {
691 	int ret = 0;
692 	struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
693 
694 	if (!IS_ERR(alg)) {
695 		crypto_mod_put(alg);
696 		ret = 1;
697 	}
698 
699 	return ret;
700 }
701 EXPORT_SYMBOL_GPL(crypto_has_alg);
702 
703 void crypto_req_done(void *data, int err)
704 {
705 	struct crypto_wait *wait = data;
706 
707 	if (err == -EINPROGRESS)
708 		return;
709 
710 	wait->err = err;
711 	complete(&wait->completion);
712 }
713 EXPORT_SYMBOL_GPL(crypto_req_done);
714 
715 void crypto_destroy_alg(struct crypto_alg *alg)
716 {
717 	if (alg->cra_type && alg->cra_type->destroy)
718 		alg->cra_type->destroy(alg);
719 	if (alg->cra_destroy)
720 		alg->cra_destroy(alg);
721 }
722 EXPORT_SYMBOL_GPL(crypto_destroy_alg);
723 
724 struct crypto_async_request *crypto_request_clone(
725 	struct crypto_async_request *req, size_t total, gfp_t gfp)
726 {
727 	struct crypto_tfm *tfm = req->tfm;
728 	struct crypto_async_request *nreq;
729 
730 	nreq = kmemdup(req, total, gfp);
731 	if (!nreq) {
732 		req->tfm = tfm->fb;
733 		return req;
734 	}
735 
736 	nreq->flags &= ~CRYPTO_TFM_REQ_ON_STACK;
737 	return nreq;
738 }
739 EXPORT_SYMBOL_GPL(crypto_request_clone);
740 
741 MODULE_DESCRIPTION("Cryptographic core API");
742 MODULE_LICENSE("GPL");
743