xref: /linux/crypto/api.c (revision 17f7b983)
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 #ifndef CONFIG_CRYPTO_MANAGER_DISABLE_TESTS
35 DEFINE_STATIC_KEY_FALSE(__crypto_boot_test_finished);
36 EXPORT_SYMBOL_GPL(__crypto_boot_test_finished);
37 #endif
38 
39 static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg);
40 
crypto_mod_get(struct crypto_alg * alg)41 struct crypto_alg *crypto_mod_get(struct crypto_alg *alg)
42 {
43 	return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
44 }
45 EXPORT_SYMBOL_GPL(crypto_mod_get);
46 
crypto_mod_put(struct crypto_alg * alg)47 void crypto_mod_put(struct crypto_alg *alg)
48 {
49 	struct module *module = alg->cra_module;
50 
51 	crypto_alg_put(alg);
52 	module_put(module);
53 }
54 EXPORT_SYMBOL_GPL(crypto_mod_put);
55 
__crypto_alg_lookup(const char * name,u32 type,u32 mask)56 static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
57 					      u32 mask)
58 {
59 	struct crypto_alg *q, *alg = NULL;
60 	int best = -2;
61 
62 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
63 		int exact, fuzzy;
64 
65 		if (crypto_is_moribund(q))
66 			continue;
67 
68 		if ((q->cra_flags ^ type) & mask)
69 			continue;
70 
71 		if (crypto_is_larval(q) &&
72 		    !crypto_is_test_larval((struct crypto_larval *)q) &&
73 		    ((struct crypto_larval *)q)->mask != mask)
74 			continue;
75 
76 		exact = !strcmp(q->cra_driver_name, name);
77 		fuzzy = !strcmp(q->cra_name, name);
78 		if (!exact && !(fuzzy && q->cra_priority > best))
79 			continue;
80 
81 		if (unlikely(!crypto_mod_get(q)))
82 			continue;
83 
84 		best = q->cra_priority;
85 		if (alg)
86 			crypto_mod_put(alg);
87 		alg = q;
88 
89 		if (exact)
90 			break;
91 	}
92 
93 	return alg;
94 }
95 
crypto_larval_destroy(struct crypto_alg * alg)96 static void crypto_larval_destroy(struct crypto_alg *alg)
97 {
98 	struct crypto_larval *larval = (void *)alg;
99 
100 	BUG_ON(!crypto_is_larval(alg));
101 	if (!IS_ERR_OR_NULL(larval->adult))
102 		crypto_mod_put(larval->adult);
103 	kfree(larval);
104 }
105 
crypto_larval_alloc(const char * name,u32 type,u32 mask)106 struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask)
107 {
108 	struct crypto_larval *larval;
109 
110 	larval = kzalloc(sizeof(*larval), GFP_KERNEL);
111 	if (!larval)
112 		return ERR_PTR(-ENOMEM);
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 
crypto_larval_add(const char * name,u32 type,u32 mask)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);
150 	}
151 
152 	return alg;
153 }
154 
crypto_larval_kill(struct crypto_alg * alg)155 void crypto_larval_kill(struct crypto_alg *alg)
156 {
157 	struct crypto_larval *larval = (void *)alg;
158 
159 	down_write(&crypto_alg_sem);
160 	list_del(&alg->cra_list);
161 	up_write(&crypto_alg_sem);
162 	complete_all(&larval->completion);
163 	crypto_alg_put(alg);
164 }
165 EXPORT_SYMBOL_GPL(crypto_larval_kill);
166 
crypto_wait_for_test(struct crypto_larval * larval)167 void crypto_wait_for_test(struct crypto_larval *larval)
168 {
169 	int err;
170 
171 	err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
172 	if (WARN_ON_ONCE(err != NOTIFY_STOP))
173 		goto out;
174 
175 	err = wait_for_completion_killable(&larval->completion);
176 	WARN_ON(err);
177 out:
178 	crypto_larval_kill(&larval->alg);
179 }
180 EXPORT_SYMBOL_GPL(crypto_wait_for_test);
181 
crypto_start_test(struct crypto_larval * larval)182 static void crypto_start_test(struct crypto_larval *larval)
183 {
184 	if (!crypto_is_test_larval(larval))
185 		return;
186 
187 	if (larval->test_started)
188 		return;
189 
190 	down_write(&crypto_alg_sem);
191 	if (larval->test_started) {
192 		up_write(&crypto_alg_sem);
193 		return;
194 	}
195 
196 	larval->test_started = true;
197 	up_write(&crypto_alg_sem);
198 
199 	crypto_wait_for_test(larval);
200 }
201 
crypto_larval_wait(struct crypto_alg * alg)202 static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg)
203 {
204 	struct crypto_larval *larval = (void *)alg;
205 	long timeout;
206 
207 	if (!crypto_boot_test_finished())
208 		crypto_start_test(larval);
209 
210 	timeout = wait_for_completion_killable_timeout(
211 		&larval->completion, 60 * HZ);
212 
213 	alg = larval->adult;
214 	if (timeout < 0)
215 		alg = ERR_PTR(-EINTR);
216 	else if (!timeout)
217 		alg = ERR_PTR(-ETIMEDOUT);
218 	else if (!alg)
219 		alg = ERR_PTR(-ENOENT);
220 	else if (IS_ERR(alg))
221 		;
222 	else if (crypto_is_test_larval(larval) &&
223 		 !(alg->cra_flags & CRYPTO_ALG_TESTED))
224 		alg = ERR_PTR(-EAGAIN);
225 	else if (alg->cra_flags & CRYPTO_ALG_FIPS_INTERNAL)
226 		alg = ERR_PTR(-EAGAIN);
227 	else if (!crypto_mod_get(alg))
228 		alg = ERR_PTR(-EAGAIN);
229 	crypto_mod_put(&larval->alg);
230 
231 	return alg;
232 }
233 
crypto_alg_lookup(const char * name,u32 type,u32 mask)234 static struct crypto_alg *crypto_alg_lookup(const char *name, u32 type,
235 					    u32 mask)
236 {
237 	const u32 fips = CRYPTO_ALG_FIPS_INTERNAL;
238 	struct crypto_alg *alg;
239 	u32 test = 0;
240 
241 	if (!((type | mask) & CRYPTO_ALG_TESTED))
242 		test |= CRYPTO_ALG_TESTED;
243 
244 	down_read(&crypto_alg_sem);
245 	alg = __crypto_alg_lookup(name, (type | test) & ~fips,
246 				  (mask | test) & ~fips);
247 	if (alg) {
248 		if (((type | mask) ^ fips) & fips)
249 			mask |= fips;
250 		mask &= fips;
251 
252 		if (!crypto_is_larval(alg) &&
253 		    ((type ^ alg->cra_flags) & mask)) {
254 			/* Algorithm is disallowed in FIPS mode. */
255 			crypto_mod_put(alg);
256 			alg = ERR_PTR(-ENOENT);
257 		}
258 	} else if (test) {
259 		alg = __crypto_alg_lookup(name, type, mask);
260 		if (alg && !crypto_is_larval(alg)) {
261 			/* Test failed */
262 			crypto_mod_put(alg);
263 			alg = ERR_PTR(-ELIBBAD);
264 		}
265 	}
266 	up_read(&crypto_alg_sem);
267 
268 	return alg;
269 }
270 
crypto_larval_lookup(const char * name,u32 type,u32 mask)271 static struct crypto_alg *crypto_larval_lookup(const char *name, u32 type,
272 					       u32 mask)
273 {
274 	struct crypto_alg *alg;
275 
276 	if (!name)
277 		return ERR_PTR(-ENOENT);
278 
279 	type &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
280 	mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
281 
282 	alg = crypto_alg_lookup(name, type, mask);
283 	if (!alg && !(mask & CRYPTO_NOLOAD)) {
284 		request_module("crypto-%s", name);
285 
286 		if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
287 		      CRYPTO_ALG_NEED_FALLBACK))
288 			request_module("crypto-%s-all", name);
289 
290 		alg = crypto_alg_lookup(name, type, mask);
291 	}
292 
293 	if (!IS_ERR_OR_NULL(alg) && crypto_is_larval(alg))
294 		alg = crypto_larval_wait(alg);
295 	else if (!alg)
296 		alg = crypto_larval_add(name, type, mask);
297 
298 	return alg;
299 }
300 
crypto_probing_notify(unsigned long val,void * v)301 int crypto_probing_notify(unsigned long val, void *v)
302 {
303 	int ok;
304 
305 	ok = blocking_notifier_call_chain(&crypto_chain, val, v);
306 	if (ok == NOTIFY_DONE) {
307 		request_module("cryptomgr");
308 		ok = blocking_notifier_call_chain(&crypto_chain, val, v);
309 	}
310 
311 	return ok;
312 }
313 EXPORT_SYMBOL_GPL(crypto_probing_notify);
314 
crypto_alg_mod_lookup(const char * name,u32 type,u32 mask)315 struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
316 {
317 	struct crypto_alg *alg;
318 	struct crypto_alg *larval;
319 	int ok;
320 
321 	/*
322 	 * If the internal flag is set for a cipher, require a caller to
323 	 * invoke the cipher with the internal flag to use that cipher.
324 	 * Also, if a caller wants to allocate a cipher that may or may
325 	 * not be an internal cipher, use type | CRYPTO_ALG_INTERNAL and
326 	 * !(mask & CRYPTO_ALG_INTERNAL).
327 	 */
328 	if (!((type | mask) & CRYPTO_ALG_INTERNAL))
329 		mask |= CRYPTO_ALG_INTERNAL;
330 
331 	larval = crypto_larval_lookup(name, type, mask);
332 	if (IS_ERR(larval) || !crypto_is_larval(larval))
333 		return larval;
334 
335 	ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
336 
337 	if (ok == NOTIFY_STOP)
338 		alg = crypto_larval_wait(larval);
339 	else {
340 		crypto_mod_put(larval);
341 		alg = ERR_PTR(-ENOENT);
342 	}
343 	crypto_larval_kill(larval);
344 	return alg;
345 }
346 EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
347 
crypto_exit_ops(struct crypto_tfm * tfm)348 static void crypto_exit_ops(struct crypto_tfm *tfm)
349 {
350 	const struct crypto_type *type = tfm->__crt_alg->cra_type;
351 
352 	if (type && tfm->exit)
353 		tfm->exit(tfm);
354 }
355 
crypto_ctxsize(struct crypto_alg * alg,u32 type,u32 mask)356 static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
357 {
358 	const struct crypto_type *type_obj = alg->cra_type;
359 	unsigned int len;
360 
361 	len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
362 	if (type_obj)
363 		return len + type_obj->ctxsize(alg, type, mask);
364 
365 	switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
366 	default:
367 		BUG();
368 
369 	case CRYPTO_ALG_TYPE_CIPHER:
370 		len += crypto_cipher_ctxsize(alg);
371 		break;
372 
373 	case CRYPTO_ALG_TYPE_COMPRESS:
374 		len += crypto_compress_ctxsize(alg);
375 		break;
376 	}
377 
378 	return len;
379 }
380 
crypto_shoot_alg(struct crypto_alg * alg)381 void crypto_shoot_alg(struct crypto_alg *alg)
382 {
383 	down_write(&crypto_alg_sem);
384 	alg->cra_flags |= CRYPTO_ALG_DYING;
385 	up_write(&crypto_alg_sem);
386 }
387 EXPORT_SYMBOL_GPL(crypto_shoot_alg);
388 
__crypto_alloc_tfmgfp(struct crypto_alg * alg,u32 type,u32 mask,gfp_t gfp)389 struct crypto_tfm *__crypto_alloc_tfmgfp(struct crypto_alg *alg, u32 type,
390 					 u32 mask, gfp_t gfp)
391 {
392 	struct crypto_tfm *tfm;
393 	unsigned int tfm_size;
394 	int err = -ENOMEM;
395 
396 	tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
397 	tfm = kzalloc(tfm_size, gfp);
398 	if (tfm == NULL)
399 		goto out_err;
400 
401 	tfm->__crt_alg = alg;
402 	refcount_set(&tfm->refcnt, 1);
403 
404 	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
405 		goto cra_init_failed;
406 
407 	goto out;
408 
409 cra_init_failed:
410 	crypto_exit_ops(tfm);
411 	if (err == -EAGAIN)
412 		crypto_shoot_alg(alg);
413 	kfree(tfm);
414 out_err:
415 	tfm = ERR_PTR(err);
416 out:
417 	return tfm;
418 }
419 EXPORT_SYMBOL_GPL(__crypto_alloc_tfmgfp);
420 
__crypto_alloc_tfm(struct crypto_alg * alg,u32 type,u32 mask)421 struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
422 				      u32 mask)
423 {
424 	return __crypto_alloc_tfmgfp(alg, type, mask, GFP_KERNEL);
425 }
426 EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
427 
428 /*
429  *	crypto_alloc_base - Locate algorithm and allocate transform
430  *	@alg_name: Name of algorithm
431  *	@type: Type of algorithm
432  *	@mask: Mask for type comparison
433  *
434  *	This function should not be used by new algorithm types.
435  *	Please use crypto_alloc_tfm instead.
436  *
437  *	crypto_alloc_base() will first attempt to locate an already loaded
438  *	algorithm.  If that fails and the kernel supports dynamically loadable
439  *	modules, it will then attempt to load a module of the same name or
440  *	alias.  If that fails it will send a query to any loaded crypto manager
441  *	to construct an algorithm on the fly.  A refcount is grabbed on the
442  *	algorithm which is then associated with the new transform.
443  *
444  *	The returned transform is of a non-determinate type.  Most people
445  *	should use one of the more specific allocation functions such as
446  *	crypto_alloc_skcipher().
447  *
448  *	In case of error the return value is an error pointer.
449  */
crypto_alloc_base(const char * alg_name,u32 type,u32 mask)450 struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
451 {
452 	struct crypto_tfm *tfm;
453 	int err;
454 
455 	for (;;) {
456 		struct crypto_alg *alg;
457 
458 		alg = crypto_alg_mod_lookup(alg_name, type, mask);
459 		if (IS_ERR(alg)) {
460 			err = PTR_ERR(alg);
461 			goto err;
462 		}
463 
464 		tfm = __crypto_alloc_tfm(alg, type, mask);
465 		if (!IS_ERR(tfm))
466 			return tfm;
467 
468 		crypto_mod_put(alg);
469 		err = PTR_ERR(tfm);
470 
471 err:
472 		if (err != -EAGAIN)
473 			break;
474 		if (fatal_signal_pending(current)) {
475 			err = -EINTR;
476 			break;
477 		}
478 	}
479 
480 	return ERR_PTR(err);
481 }
482 EXPORT_SYMBOL_GPL(crypto_alloc_base);
483 
crypto_alloc_tfmmem(struct crypto_alg * alg,const struct crypto_type * frontend,int node,gfp_t gfp)484 static void *crypto_alloc_tfmmem(struct crypto_alg *alg,
485 				 const struct crypto_type *frontend, int node,
486 				 gfp_t gfp)
487 {
488 	struct crypto_tfm *tfm;
489 	unsigned int tfmsize;
490 	unsigned int total;
491 	char *mem;
492 
493 	tfmsize = frontend->tfmsize;
494 	total = tfmsize + sizeof(*tfm) + frontend->extsize(alg);
495 
496 	mem = kzalloc_node(total, gfp, node);
497 	if (mem == NULL)
498 		return ERR_PTR(-ENOMEM);
499 
500 	tfm = (struct crypto_tfm *)(mem + tfmsize);
501 	tfm->__crt_alg = alg;
502 	tfm->node = node;
503 	refcount_set(&tfm->refcnt, 1);
504 
505 	return mem;
506 }
507 
crypto_create_tfm_node(struct crypto_alg * alg,const struct crypto_type * frontend,int node)508 void *crypto_create_tfm_node(struct crypto_alg *alg,
509 			     const struct crypto_type *frontend,
510 			     int node)
511 {
512 	struct crypto_tfm *tfm;
513 	char *mem;
514 	int err;
515 
516 	mem = crypto_alloc_tfmmem(alg, frontend, node, GFP_KERNEL);
517 	if (IS_ERR(mem))
518 		goto out;
519 
520 	tfm = (struct crypto_tfm *)(mem + frontend->tfmsize);
521 
522 	err = frontend->init_tfm(tfm);
523 	if (err)
524 		goto out_free_tfm;
525 
526 	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
527 		goto cra_init_failed;
528 
529 	goto out;
530 
531 cra_init_failed:
532 	crypto_exit_ops(tfm);
533 out_free_tfm:
534 	if (err == -EAGAIN)
535 		crypto_shoot_alg(alg);
536 	kfree(mem);
537 	mem = ERR_PTR(err);
538 out:
539 	return mem;
540 }
541 EXPORT_SYMBOL_GPL(crypto_create_tfm_node);
542 
crypto_clone_tfm(const struct crypto_type * frontend,struct crypto_tfm * otfm)543 void *crypto_clone_tfm(const struct crypto_type *frontend,
544 		       struct crypto_tfm *otfm)
545 {
546 	struct crypto_alg *alg = otfm->__crt_alg;
547 	struct crypto_tfm *tfm;
548 	char *mem;
549 
550 	mem = ERR_PTR(-ESTALE);
551 	if (unlikely(!crypto_mod_get(alg)))
552 		goto out;
553 
554 	mem = crypto_alloc_tfmmem(alg, frontend, otfm->node, GFP_ATOMIC);
555 	if (IS_ERR(mem)) {
556 		crypto_mod_put(alg);
557 		goto out;
558 	}
559 
560 	tfm = (struct crypto_tfm *)(mem + frontend->tfmsize);
561 	tfm->crt_flags = otfm->crt_flags;
562 	tfm->exit = otfm->exit;
563 
564 out:
565 	return mem;
566 }
567 EXPORT_SYMBOL_GPL(crypto_clone_tfm);
568 
crypto_find_alg(const char * alg_name,const struct crypto_type * frontend,u32 type,u32 mask)569 struct crypto_alg *crypto_find_alg(const char *alg_name,
570 				   const struct crypto_type *frontend,
571 				   u32 type, u32 mask)
572 {
573 	if (frontend) {
574 		type &= frontend->maskclear;
575 		mask &= frontend->maskclear;
576 		type |= frontend->type;
577 		mask |= frontend->maskset;
578 	}
579 
580 	return crypto_alg_mod_lookup(alg_name, type, mask);
581 }
582 EXPORT_SYMBOL_GPL(crypto_find_alg);
583 
584 /*
585  *	crypto_alloc_tfm_node - Locate algorithm and allocate transform
586  *	@alg_name: Name of algorithm
587  *	@frontend: Frontend algorithm type
588  *	@type: Type of algorithm
589  *	@mask: Mask for type comparison
590  *	@node: NUMA node in which users desire to put requests, if node is
591  *		NUMA_NO_NODE, it means users have no special requirement.
592  *
593  *	crypto_alloc_tfm() will first attempt to locate an already loaded
594  *	algorithm.  If that fails and the kernel supports dynamically loadable
595  *	modules, it will then attempt to load a module of the same name or
596  *	alias.  If that fails it will send a query to any loaded crypto manager
597  *	to construct an algorithm on the fly.  A refcount is grabbed on the
598  *	algorithm which is then associated with the new transform.
599  *
600  *	The returned transform is of a non-determinate type.  Most people
601  *	should use one of the more specific allocation functions such as
602  *	crypto_alloc_skcipher().
603  *
604  *	In case of error the return value is an error pointer.
605  */
606 
crypto_alloc_tfm_node(const char * alg_name,const struct crypto_type * frontend,u32 type,u32 mask,int node)607 void *crypto_alloc_tfm_node(const char *alg_name,
608 		       const struct crypto_type *frontend, u32 type, u32 mask,
609 		       int node)
610 {
611 	void *tfm;
612 	int err;
613 
614 	for (;;) {
615 		struct crypto_alg *alg;
616 
617 		alg = crypto_find_alg(alg_name, frontend, type, mask);
618 		if (IS_ERR(alg)) {
619 			err = PTR_ERR(alg);
620 			goto err;
621 		}
622 
623 		tfm = crypto_create_tfm_node(alg, frontend, node);
624 		if (!IS_ERR(tfm))
625 			return tfm;
626 
627 		crypto_mod_put(alg);
628 		err = PTR_ERR(tfm);
629 
630 err:
631 		if (err != -EAGAIN)
632 			break;
633 		if (fatal_signal_pending(current)) {
634 			err = -EINTR;
635 			break;
636 		}
637 	}
638 
639 	return ERR_PTR(err);
640 }
641 EXPORT_SYMBOL_GPL(crypto_alloc_tfm_node);
642 
643 /*
644  *	crypto_destroy_tfm - Free crypto transform
645  *	@mem: Start of tfm slab
646  *	@tfm: Transform to free
647  *
648  *	This function frees up the transform and any associated resources,
649  *	then drops the refcount on the associated algorithm.
650  */
crypto_destroy_tfm(void * mem,struct crypto_tfm * tfm)651 void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
652 {
653 	struct crypto_alg *alg;
654 
655 	if (IS_ERR_OR_NULL(mem))
656 		return;
657 
658 	if (!refcount_dec_and_test(&tfm->refcnt))
659 		return;
660 	alg = tfm->__crt_alg;
661 
662 	if (!tfm->exit && alg->cra_exit)
663 		alg->cra_exit(tfm);
664 	crypto_exit_ops(tfm);
665 	crypto_mod_put(alg);
666 	kfree_sensitive(mem);
667 }
668 EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
669 
crypto_has_alg(const char * name,u32 type,u32 mask)670 int crypto_has_alg(const char *name, u32 type, u32 mask)
671 {
672 	int ret = 0;
673 	struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
674 
675 	if (!IS_ERR(alg)) {
676 		crypto_mod_put(alg);
677 		ret = 1;
678 	}
679 
680 	return ret;
681 }
682 EXPORT_SYMBOL_GPL(crypto_has_alg);
683 
crypto_req_done(void * data,int err)684 void crypto_req_done(void *data, int err)
685 {
686 	struct crypto_wait *wait = data;
687 
688 	if (err == -EINPROGRESS)
689 		return;
690 
691 	wait->err = err;
692 	complete(&wait->completion);
693 }
694 EXPORT_SYMBOL_GPL(crypto_req_done);
695 
696 MODULE_DESCRIPTION("Cryptographic core API");
697 MODULE_LICENSE("GPL");
698