xref: /linux/crypto/api.c (revision 37a93dd5c49b5fda807fd204edf2547c3493319c) 
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 	__must_hold_shared(&crypto_alg_sem)
61 {
62 	struct crypto_alg *q, *alg = NULL;
63 	int best = -2;
64 
65 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
66 		int exact, fuzzy;
67 
68 		if (crypto_is_moribund(q))
69 			continue;
70 
71 		if ((q->cra_flags ^ type) & mask)
72 			continue;
73 
74 		exact = !strcmp(q->cra_driver_name, name);
75 		fuzzy = !strcmp(q->cra_name, name);
76 		if (!exact && !(fuzzy && q->cra_priority > best))
77 			continue;
78 
79 		if (unlikely(!crypto_mod_get(q)))
80 			continue;
81 
82 		best = q->cra_priority;
83 		if (alg)
84 			crypto_mod_put(alg);
85 		alg = q;
86 
87 		if (exact)
88 			break;
89 	}
90 
91 	return alg;
92 }
93 
94 static void crypto_larval_destroy(struct crypto_alg *alg)
95 {
96 	struct crypto_larval *larval = (void *)alg;
97 
98 	BUG_ON(!crypto_is_larval(alg));
99 	if (!IS_ERR_OR_NULL(larval->adult))
100 		crypto_mod_put(larval->adult);
101 	kfree(larval);
102 }
103 
104 struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask)
105 {
106 	struct crypto_larval *larval;
107 
108 	larval = kzalloc(sizeof(*larval), GFP_KERNEL);
109 	if (!larval)
110 		return ERR_PTR(-ENOMEM);
111 
112 	type &= ~CRYPTO_ALG_TYPE_MASK | (mask ?: CRYPTO_ALG_TYPE_MASK);
113 
114 	larval->mask = mask;
115 	larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type;
116 	larval->alg.cra_priority = -1;
117 	larval->alg.cra_destroy = crypto_larval_destroy;
118 
119 	strscpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
120 	init_completion(&larval->completion);
121 
122 	return larval;
123 }
124 EXPORT_SYMBOL_GPL(crypto_larval_alloc);
125 
126 static struct crypto_alg *crypto_larval_add(const char *name, u32 type,
127 					    u32 mask)
128 {
129 	struct crypto_alg *alg;
130 	struct crypto_larval *larval;
131 
132 	larval = crypto_larval_alloc(name, type, mask);
133 	if (IS_ERR(larval))
134 		return ERR_CAST(larval);
135 
136 	refcount_set(&larval->alg.cra_refcnt, 2);
137 
138 	down_write(&crypto_alg_sem);
139 	alg = __crypto_alg_lookup(name, type, mask);
140 	if (!alg) {
141 		alg = &larval->alg;
142 		list_add(&alg->cra_list, &crypto_alg_list);
143 	}
144 	up_write(&crypto_alg_sem);
145 
146 	if (alg != &larval->alg) {
147 		kfree(larval);
148 		if (crypto_is_larval(alg))
149 			alg = crypto_larval_wait(alg, type, mask);
150 	}
151 
152 	return alg;
153 }
154 
155 static void crypto_larval_kill(struct crypto_larval *larval)
156 {
157 	bool unlinked;
158 
159 	down_write(&crypto_alg_sem);
160 	unlinked = list_empty(&larval->alg.cra_list);
161 	if (!unlinked)
162 		list_del_init(&larval->alg.cra_list);
163 	up_write(&crypto_alg_sem);
164 
165 	if (unlinked)
166 		return;
167 
168 	complete_all(&larval->completion);
169 	crypto_alg_put(&larval->alg);
170 }
171 
172 void crypto_schedule_test(struct crypto_larval *larval)
173 {
174 	int err;
175 
176 	err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
177 	WARN_ON_ONCE(err != NOTIFY_STOP);
178 }
179 EXPORT_SYMBOL_GPL(crypto_schedule_test);
180 
181 static void crypto_start_test(struct crypto_larval *larval)
182 {
183 	if (!crypto_is_test_larval(larval))
184 		return;
185 
186 	if (larval->test_started)
187 		return;
188 
189 	down_write(&crypto_alg_sem);
190 	if (larval->test_started) {
191 		up_write(&crypto_alg_sem);
192 		return;
193 	}
194 
195 	larval->test_started = true;
196 	up_write(&crypto_alg_sem);
197 
198 	crypto_schedule_test(larval);
199 }
200 
201 static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg,
202 					     u32 type, u32 mask)
203 {
204 	struct crypto_larval *larval;
205 	long time_left;
206 
207 again:
208 	larval = container_of(alg, struct crypto_larval, alg);
209 
210 	if (!crypto_boot_test_finished())
211 		crypto_start_test(larval);
212 
213 	time_left = wait_for_completion_killable_timeout(
214 		&larval->completion, 60 * HZ);
215 
216 	alg = larval->adult;
217 	if (time_left < 0)
218 		alg = ERR_PTR(-EINTR);
219 	else if (!time_left) {
220 		if (crypto_is_test_larval(larval))
221 			crypto_larval_kill(larval);
222 		alg = ERR_PTR(-ETIMEDOUT);
223 	} else if (!alg || PTR_ERR(alg) == -EEXIST) {
224 		int err = alg ? -EEXIST : -EAGAIN;
225 
226 		/*
227 		 * EEXIST is expected because two probes can be scheduled
228 		 * at the same time with one using alg_name and the other
229 		 * using driver_name.  Do a re-lookup but do not retry in
230 		 * case we hit a quirk like gcm_base(ctr(aes),...) which
231 		 * will never match.
232 		 */
233 		alg = &larval->alg;
234 		alg = crypto_alg_lookup(alg->cra_name, type, mask) ?:
235 		      ERR_PTR(err);
236 	} else if (IS_ERR(alg))
237 		;
238 	else if (crypto_is_test_larval(larval) &&
239 		 !(alg->cra_flags & CRYPTO_ALG_TESTED))
240 		alg = ERR_PTR(-EAGAIN);
241 	else if (alg->cra_flags & CRYPTO_ALG_FIPS_INTERNAL)
242 		alg = ERR_PTR(-EAGAIN);
243 	else if (!crypto_mod_get(alg))
244 		alg = ERR_PTR(-EAGAIN);
245 	crypto_mod_put(&larval->alg);
246 
247 	if (!IS_ERR(alg) && crypto_is_larval(alg))
248 		goto again;
249 
250 	return alg;
251 }
252 
253 static struct crypto_alg *crypto_alg_lookup(const char *name, u32 type,
254 					    u32 mask)
255 {
256 	const u32 fips = CRYPTO_ALG_FIPS_INTERNAL;
257 	struct crypto_alg *alg;
258 	u32 test = 0;
259 
260 	if (!((type | mask) & CRYPTO_ALG_TESTED))
261 		test |= CRYPTO_ALG_TESTED;
262 
263 	down_read(&crypto_alg_sem);
264 	alg = __crypto_alg_lookup(name, (type | test) & ~fips,
265 				  (mask | test) & ~fips);
266 	if (alg) {
267 		if (((type | mask) ^ fips) & fips)
268 			mask |= fips;
269 		mask &= fips;
270 
271 		if (!crypto_is_larval(alg) &&
272 		    ((type ^ alg->cra_flags) & mask)) {
273 			/* Algorithm is disallowed in FIPS mode. */
274 			crypto_mod_put(alg);
275 			alg = ERR_PTR(-ENOENT);
276 		}
277 	} else if (test) {
278 		alg = __crypto_alg_lookup(name, type, mask);
279 		if (alg && !crypto_is_larval(alg)) {
280 			/* Test failed */
281 			crypto_mod_put(alg);
282 			alg = ERR_PTR(-ELIBBAD);
283 		}
284 	}
285 	up_read(&crypto_alg_sem);
286 
287 	return alg;
288 }
289 
290 static struct crypto_alg *crypto_larval_lookup(const char *name, u32 type,
291 					       u32 mask)
292 {
293 	struct crypto_alg *alg;
294 
295 	if (!name)
296 		return ERR_PTR(-ENOENT);
297 
298 	type &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
299 	mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
300 
301 	alg = crypto_alg_lookup(name, type, mask);
302 	if (!alg && !(mask & CRYPTO_NOLOAD)) {
303 		request_module("crypto-%s", name);
304 
305 		if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
306 		      CRYPTO_ALG_NEED_FALLBACK))
307 			request_module("crypto-%s-all", name);
308 
309 		alg = crypto_alg_lookup(name, type, mask);
310 	}
311 
312 	if (!IS_ERR_OR_NULL(alg) && crypto_is_larval(alg))
313 		alg = crypto_larval_wait(alg, type, mask);
314 	else if (alg)
315 		;
316 	else if (!(mask & CRYPTO_ALG_TESTED))
317 		alg = crypto_larval_add(name, type, mask);
318 	else
319 		alg = ERR_PTR(-ENOENT);
320 
321 	return alg;
322 }
323 
324 int crypto_probing_notify(unsigned long val, void *v)
325 {
326 	int ok;
327 
328 	ok = blocking_notifier_call_chain(&crypto_chain, val, v);
329 	if (ok == NOTIFY_DONE) {
330 		request_module("cryptomgr");
331 		ok = blocking_notifier_call_chain(&crypto_chain, val, v);
332 	}
333 
334 	return ok;
335 }
336 EXPORT_SYMBOL_GPL(crypto_probing_notify);
337 
338 struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
339 {
340 	struct crypto_alg *alg;
341 	struct crypto_alg *larval;
342 	int ok;
343 
344 	/*
345 	 * If the internal flag is set for a cipher, require a caller to
346 	 * invoke the cipher with the internal flag to use that cipher.
347 	 * Also, if a caller wants to allocate a cipher that may or may
348 	 * not be an internal cipher, use type | CRYPTO_ALG_INTERNAL and
349 	 * !(mask & CRYPTO_ALG_INTERNAL).
350 	 */
351 	if (!((type | mask) & CRYPTO_ALG_INTERNAL))
352 		mask |= CRYPTO_ALG_INTERNAL;
353 
354 	larval = crypto_larval_lookup(name, type, mask);
355 	if (IS_ERR(larval) || !crypto_is_larval(larval))
356 		return larval;
357 
358 	ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
359 
360 	if (ok == NOTIFY_STOP)
361 		alg = crypto_larval_wait(larval, type, mask);
362 	else {
363 		crypto_mod_put(larval);
364 		alg = ERR_PTR(-ENOENT);
365 	}
366 	crypto_larval_kill(container_of(larval, struct crypto_larval, alg));
367 	return alg;
368 }
369 EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
370 
371 static void crypto_exit_ops(struct crypto_tfm *tfm)
372 {
373 	const struct crypto_type *type = tfm->__crt_alg->cra_type;
374 
375 	if (type && tfm->exit)
376 		tfm->exit(tfm);
377 }
378 
379 static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
380 {
381 	const struct crypto_type *type_obj = alg->cra_type;
382 	unsigned int len;
383 
384 	len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
385 	if (type_obj)
386 		return len + type_obj->ctxsize(alg, type, mask);
387 
388 	switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
389 	default:
390 		BUG();
391 
392 	case CRYPTO_ALG_TYPE_CIPHER:
393 		len += crypto_cipher_ctxsize(alg);
394 		break;
395 	}
396 
397 	return len;
398 }
399 
400 void crypto_shoot_alg(struct crypto_alg *alg)
401 {
402 	down_write(&crypto_alg_sem);
403 	alg->cra_flags |= CRYPTO_ALG_DYING;
404 	up_write(&crypto_alg_sem);
405 }
406 EXPORT_SYMBOL_GPL(crypto_shoot_alg);
407 
408 struct crypto_tfm *__crypto_alloc_tfmgfp(struct crypto_alg *alg, u32 type,
409 					 u32 mask, gfp_t gfp)
410 {
411 	struct crypto_tfm *tfm;
412 	unsigned int tfm_size;
413 	int err = -ENOMEM;
414 
415 	tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
416 	tfm = kzalloc(tfm_size, gfp);
417 	if (tfm == NULL)
418 		goto out_err;
419 
420 	tfm->__crt_alg = alg;
421 	refcount_set(&tfm->refcnt, 1);
422 
423 	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
424 		goto cra_init_failed;
425 
426 	goto out;
427 
428 cra_init_failed:
429 	crypto_exit_ops(tfm);
430 	if (err == -EAGAIN)
431 		crypto_shoot_alg(alg);
432 	kfree(tfm);
433 out_err:
434 	tfm = ERR_PTR(err);
435 out:
436 	return tfm;
437 }
438 EXPORT_SYMBOL_GPL(__crypto_alloc_tfmgfp);
439 
440 struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
441 				      u32 mask)
442 {
443 	return __crypto_alloc_tfmgfp(alg, type, mask, GFP_KERNEL);
444 }
445 EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
446 
447 /*
448  *	crypto_alloc_base - Locate algorithm and allocate transform
449  *	@alg_name: Name of algorithm
450  *	@type: Type of algorithm
451  *	@mask: Mask for type comparison
452  *
453  *	This function should not be used by new algorithm types.
454  *	Please use crypto_alloc_tfm instead.
455  *
456  *	crypto_alloc_base() will first attempt to locate an already loaded
457  *	algorithm.  If that fails and the kernel supports dynamically loadable
458  *	modules, it will then attempt to load a module of the same name or
459  *	alias.  If that fails it will send a query to any loaded crypto manager
460  *	to construct an algorithm on the fly.  A refcount is grabbed on the
461  *	algorithm which is then associated with the new transform.
462  *
463  *	The returned transform is of a non-determinate type.  Most people
464  *	should use one of the more specific allocation functions such as
465  *	crypto_alloc_skcipher().
466  *
467  *	In case of error the return value is an error pointer.
468  */
469 struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
470 {
471 	struct crypto_tfm *tfm;
472 	int err;
473 
474 	for (;;) {
475 		struct crypto_alg *alg;
476 
477 		alg = crypto_alg_mod_lookup(alg_name, type, mask);
478 		if (IS_ERR(alg)) {
479 			err = PTR_ERR(alg);
480 			goto err;
481 		}
482 
483 		tfm = __crypto_alloc_tfm(alg, type, mask);
484 		if (!IS_ERR(tfm))
485 			return tfm;
486 
487 		crypto_mod_put(alg);
488 		err = PTR_ERR(tfm);
489 
490 err:
491 		if (err != -EAGAIN)
492 			break;
493 		if (fatal_signal_pending(current)) {
494 			err = -EINTR;
495 			break;
496 		}
497 	}
498 
499 	return ERR_PTR(err);
500 }
501 EXPORT_SYMBOL_GPL(crypto_alloc_base);
502 
503 static void *crypto_alloc_tfmmem(struct crypto_alg *alg,
504 				 const struct crypto_type *frontend, int node,
505 				 gfp_t gfp)
506 {
507 	struct crypto_tfm *tfm;
508 	unsigned int tfmsize;
509 	unsigned int total;
510 	char *mem;
511 
512 	tfmsize = frontend->tfmsize;
513 	total = tfmsize + sizeof(*tfm) + frontend->extsize(alg);
514 
515 	mem = kzalloc_node(total, gfp, node);
516 	if (mem == NULL)
517 		return ERR_PTR(-ENOMEM);
518 
519 	tfm = (struct crypto_tfm *)(mem + tfmsize);
520 	tfm->__crt_alg = alg;
521 	tfm->node = node;
522 	refcount_set(&tfm->refcnt, 1);
523 
524 	return mem;
525 }
526 
527 void *crypto_create_tfm_node(struct crypto_alg *alg,
528 			     const struct crypto_type *frontend,
529 			     int node)
530 {
531 	struct crypto_tfm *tfm;
532 	char *mem;
533 	int err;
534 
535 	mem = crypto_alloc_tfmmem(alg, frontend, node, GFP_KERNEL);
536 	if (IS_ERR(mem))
537 		goto out;
538 
539 	tfm = (struct crypto_tfm *)(mem + frontend->tfmsize);
540 	tfm->fb = tfm;
541 
542 	err = frontend->init_tfm(tfm);
543 	if (err)
544 		goto out_free_tfm;
545 
546 	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
547 		goto cra_init_failed;
548 
549 	goto out;
550 
551 cra_init_failed:
552 	crypto_exit_ops(tfm);
553 out_free_tfm:
554 	if (err == -EAGAIN)
555 		crypto_shoot_alg(alg);
556 	kfree(mem);
557 	mem = ERR_PTR(err);
558 out:
559 	return mem;
560 }
561 EXPORT_SYMBOL_GPL(crypto_create_tfm_node);
562 
563 void *crypto_clone_tfm(const struct crypto_type *frontend,
564 		       struct crypto_tfm *otfm)
565 {
566 	struct crypto_alg *alg = otfm->__crt_alg;
567 	struct crypto_tfm *tfm;
568 	char *mem;
569 
570 	mem = ERR_PTR(-ESTALE);
571 	if (unlikely(!crypto_mod_get(alg)))
572 		goto out;
573 
574 	mem = crypto_alloc_tfmmem(alg, frontend, otfm->node, GFP_ATOMIC);
575 	if (IS_ERR(mem)) {
576 		crypto_mod_put(alg);
577 		goto out;
578 	}
579 
580 	tfm = (struct crypto_tfm *)(mem + frontend->tfmsize);
581 	tfm->crt_flags = otfm->crt_flags;
582 	tfm->fb = tfm;
583 
584 out:
585 	return mem;
586 }
587 EXPORT_SYMBOL_GPL(crypto_clone_tfm);
588 
589 struct crypto_alg *crypto_find_alg(const char *alg_name,
590 				   const struct crypto_type *frontend,
591 				   u32 type, u32 mask)
592 {
593 	if (frontend) {
594 		type &= frontend->maskclear;
595 		mask &= frontend->maskclear;
596 		type |= frontend->type;
597 		mask |= frontend->maskset;
598 	}
599 
600 	return crypto_alg_mod_lookup(alg_name, type, mask);
601 }
602 EXPORT_SYMBOL_GPL(crypto_find_alg);
603 
604 /*
605  *	crypto_alloc_tfm_node - Locate algorithm and allocate transform
606  *	@alg_name: Name of algorithm
607  *	@frontend: Frontend algorithm type
608  *	@type: Type of algorithm
609  *	@mask: Mask for type comparison
610  *	@node: NUMA node in which users desire to put requests, if node is
611  *		NUMA_NO_NODE, it means users have no special requirement.
612  *
613  *	crypto_alloc_tfm() will first attempt to locate an already loaded
614  *	algorithm.  If that fails and the kernel supports dynamically loadable
615  *	modules, it will then attempt to load a module of the same name or
616  *	alias.  If that fails it will send a query to any loaded crypto manager
617  *	to construct an algorithm on the fly.  A refcount is grabbed on the
618  *	algorithm which is then associated with the new transform.
619  *
620  *	The returned transform is of a non-determinate type.  Most people
621  *	should use one of the more specific allocation functions such as
622  *	crypto_alloc_skcipher().
623  *
624  *	In case of error the return value is an error pointer.
625  */
626 
627 void *crypto_alloc_tfm_node(const char *alg_name,
628 		       const struct crypto_type *frontend, u32 type, u32 mask,
629 		       int node)
630 {
631 	void *tfm;
632 	int err;
633 
634 	for (;;) {
635 		struct crypto_alg *alg;
636 
637 		alg = crypto_find_alg(alg_name, frontend, type, mask);
638 		if (IS_ERR(alg)) {
639 			err = PTR_ERR(alg);
640 			goto err;
641 		}
642 
643 		tfm = crypto_create_tfm_node(alg, frontend, node);
644 		if (!IS_ERR(tfm))
645 			return tfm;
646 
647 		crypto_mod_put(alg);
648 		err = PTR_ERR(tfm);
649 
650 err:
651 		if (err != -EAGAIN)
652 			break;
653 		if (fatal_signal_pending(current)) {
654 			err = -EINTR;
655 			break;
656 		}
657 	}
658 
659 	return ERR_PTR(err);
660 }
661 EXPORT_SYMBOL_GPL(crypto_alloc_tfm_node);
662 
663 /*
664  *	crypto_destroy_tfm - Free crypto transform
665  *	@mem: Start of tfm slab
666  *	@tfm: Transform to free
667  *
668  *	This function frees up the transform and any associated resources,
669  *	then drops the refcount on the associated algorithm.
670  */
671 void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
672 {
673 	struct crypto_alg *alg;
674 
675 	if (IS_ERR_OR_NULL(mem))
676 		return;
677 
678 	if (!refcount_dec_and_test(&tfm->refcnt))
679 		return;
680 	alg = tfm->__crt_alg;
681 
682 	if (!tfm->exit && alg->cra_exit)
683 		alg->cra_exit(tfm);
684 	crypto_exit_ops(tfm);
685 	crypto_mod_put(alg);
686 	kfree_sensitive(mem);
687 }
688 EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
689 
690 int crypto_has_alg(const char *name, u32 type, u32 mask)
691 {
692 	int ret = 0;
693 	struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
694 
695 	if (!IS_ERR(alg)) {
696 		crypto_mod_put(alg);
697 		ret = 1;
698 	}
699 
700 	return ret;
701 }
702 EXPORT_SYMBOL_GPL(crypto_has_alg);
703 
704 void crypto_req_done(void *data, int err)
705 {
706 	struct crypto_wait *wait = data;
707 
708 	if (err == -EINPROGRESS)
709 		return;
710 
711 	wait->err = err;
712 	complete(&wait->completion);
713 }
714 EXPORT_SYMBOL_GPL(crypto_req_done);
715 
716 void crypto_destroy_alg(struct crypto_alg *alg)
717 {
718 	if (alg->cra_type && alg->cra_type->destroy)
719 		alg->cra_type->destroy(alg);
720 	if (alg->cra_destroy)
721 		alg->cra_destroy(alg);
722 }
723 EXPORT_SYMBOL_GPL(crypto_destroy_alg);
724 
725 struct crypto_async_request *crypto_request_clone(
726 	struct crypto_async_request *req, size_t total, gfp_t gfp)
727 {
728 	struct crypto_tfm *tfm = req->tfm;
729 	struct crypto_async_request *nreq;
730 
731 	nreq = kmemdup(req, total, gfp);
732 	if (!nreq) {
733 		req->tfm = tfm->fb;
734 		return req;
735 	}
736 
737 	nreq->flags &= ~CRYPTO_TFM_REQ_ON_STACK;
738 	return nreq;
739 }
740 EXPORT_SYMBOL_GPL(crypto_request_clone);
741 
742 MODULE_DESCRIPTION("Cryptographic core API");
743 MODULE_LICENSE("GPL");
744