xref: /openbmc/linux/crypto/algapi.c (revision 519b58bb)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Cryptographic API for algorithms (i.e., low-level API).
4  *
5  * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
6  */
7 
8 #include <crypto/algapi.h>
9 #include <crypto/internal/simd.h>
10 #include <linux/err.h>
11 #include <linux/errno.h>
12 #include <linux/fips.h>
13 #include <linux/init.h>
14 #include <linux/kernel.h>
15 #include <linux/list.h>
16 #include <linux/module.h>
17 #include <linux/rtnetlink.h>
18 #include <linux/slab.h>
19 #include <linux/string.h>
20 
21 #include "internal.h"
22 
23 static LIST_HEAD(crypto_template_list);
24 
25 #ifdef CONFIG_CRYPTO_MANAGER_EXTRA_TESTS
26 DEFINE_PER_CPU(bool, crypto_simd_disabled_for_test);
27 EXPORT_PER_CPU_SYMBOL_GPL(crypto_simd_disabled_for_test);
28 #endif
29 
30 static inline void crypto_check_module_sig(struct module *mod)
31 {
32 	if (fips_enabled && mod && !module_sig_ok(mod))
33 		panic("Module %s signature verification failed in FIPS mode\n",
34 		      module_name(mod));
35 }
36 
37 static int crypto_check_alg(struct crypto_alg *alg)
38 {
39 	crypto_check_module_sig(alg->cra_module);
40 
41 	if (!alg->cra_name[0] || !alg->cra_driver_name[0])
42 		return -EINVAL;
43 
44 	if (alg->cra_alignmask & (alg->cra_alignmask + 1))
45 		return -EINVAL;
46 
47 	/* General maximums for all algs. */
48 	if (alg->cra_alignmask > MAX_ALGAPI_ALIGNMASK)
49 		return -EINVAL;
50 
51 	if (alg->cra_blocksize > MAX_ALGAPI_BLOCKSIZE)
52 		return -EINVAL;
53 
54 	/* Lower maximums for specific alg types. */
55 	if (!alg->cra_type && (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
56 			       CRYPTO_ALG_TYPE_CIPHER) {
57 		if (alg->cra_alignmask > MAX_CIPHER_ALIGNMASK)
58 			return -EINVAL;
59 
60 		if (alg->cra_blocksize > MAX_CIPHER_BLOCKSIZE)
61 			return -EINVAL;
62 	}
63 
64 	if (alg->cra_priority < 0)
65 		return -EINVAL;
66 
67 	refcount_set(&alg->cra_refcnt, 1);
68 
69 	return 0;
70 }
71 
72 static void crypto_free_instance(struct crypto_instance *inst)
73 {
74 	inst->alg.cra_type->free(inst);
75 }
76 
77 static void crypto_destroy_instance(struct crypto_alg *alg)
78 {
79 	struct crypto_instance *inst = (void *)alg;
80 	struct crypto_template *tmpl = inst->tmpl;
81 
82 	crypto_free_instance(inst);
83 	crypto_tmpl_put(tmpl);
84 }
85 
86 /*
87  * This function adds a spawn to the list secondary_spawns which
88  * will be used at the end of crypto_remove_spawns to unregister
89  * instances, unless the spawn happens to be one that is depended
90  * on by the new algorithm (nalg in crypto_remove_spawns).
91  *
92  * This function is also responsible for resurrecting any algorithms
93  * in the dependency chain of nalg by unsetting n->dead.
94  */
95 static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
96 					    struct list_head *stack,
97 					    struct list_head *top,
98 					    struct list_head *secondary_spawns)
99 {
100 	struct crypto_spawn *spawn, *n;
101 
102 	spawn = list_first_entry_or_null(stack, struct crypto_spawn, list);
103 	if (!spawn)
104 		return NULL;
105 
106 	n = list_prev_entry(spawn, list);
107 	list_move(&spawn->list, secondary_spawns);
108 
109 	if (list_is_last(&n->list, stack))
110 		return top;
111 
112 	n = list_next_entry(n, list);
113 	if (!spawn->dead)
114 		n->dead = false;
115 
116 	return &n->inst->alg.cra_users;
117 }
118 
119 static void crypto_remove_instance(struct crypto_instance *inst,
120 				   struct list_head *list)
121 {
122 	struct crypto_template *tmpl = inst->tmpl;
123 
124 	if (crypto_is_dead(&inst->alg))
125 		return;
126 
127 	inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
128 
129 	if (!tmpl || !crypto_tmpl_get(tmpl))
130 		return;
131 
132 	list_move(&inst->alg.cra_list, list);
133 	hlist_del(&inst->list);
134 	inst->alg.cra_destroy = crypto_destroy_instance;
135 
136 	BUG_ON(!list_empty(&inst->alg.cra_users));
137 }
138 
139 /*
140  * Given an algorithm alg, remove all algorithms that depend on it
141  * through spawns.  If nalg is not null, then exempt any algorithms
142  * that is depended on by nalg.  This is useful when nalg itself
143  * depends on alg.
144  */
145 void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
146 			  struct crypto_alg *nalg)
147 {
148 	u32 new_type = (nalg ?: alg)->cra_flags;
149 	struct crypto_spawn *spawn, *n;
150 	LIST_HEAD(secondary_spawns);
151 	struct list_head *spawns;
152 	LIST_HEAD(stack);
153 	LIST_HEAD(top);
154 
155 	spawns = &alg->cra_users;
156 	list_for_each_entry_safe(spawn, n, spawns, list) {
157 		if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
158 			continue;
159 
160 		list_move(&spawn->list, &top);
161 	}
162 
163 	/*
164 	 * Perform a depth-first walk starting from alg through
165 	 * the cra_users tree.  The list stack records the path
166 	 * from alg to the current spawn.
167 	 */
168 	spawns = &top;
169 	do {
170 		while (!list_empty(spawns)) {
171 			struct crypto_instance *inst;
172 
173 			spawn = list_first_entry(spawns, struct crypto_spawn,
174 						 list);
175 			inst = spawn->inst;
176 
177 			list_move(&spawn->list, &stack);
178 			spawn->dead = !spawn->registered || &inst->alg != nalg;
179 
180 			if (!spawn->registered)
181 				break;
182 
183 			BUG_ON(&inst->alg == alg);
184 
185 			if (&inst->alg == nalg)
186 				break;
187 
188 			spawns = &inst->alg.cra_users;
189 
190 			/*
191 			 * Even if spawn->registered is true, the
192 			 * instance itself may still be unregistered.
193 			 * This is because it may have failed during
194 			 * registration.  Therefore we still need to
195 			 * make the following test.
196 			 *
197 			 * We may encounter an unregistered instance here, since
198 			 * an instance's spawns are set up prior to the instance
199 			 * being registered.  An unregistered instance will have
200 			 * NULL ->cra_users.next, since ->cra_users isn't
201 			 * properly initialized until registration.  But an
202 			 * unregistered instance cannot have any users, so treat
203 			 * it the same as ->cra_users being empty.
204 			 */
205 			if (spawns->next == NULL)
206 				break;
207 		}
208 	} while ((spawns = crypto_more_spawns(alg, &stack, &top,
209 					      &secondary_spawns)));
210 
211 	/*
212 	 * Remove all instances that are marked as dead.  Also
213 	 * complete the resurrection of the others by moving them
214 	 * back to the cra_users list.
215 	 */
216 	list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
217 		if (!spawn->dead)
218 			list_move(&spawn->list, &spawn->alg->cra_users);
219 		else if (spawn->registered)
220 			crypto_remove_instance(spawn->inst, list);
221 	}
222 }
223 EXPORT_SYMBOL_GPL(crypto_remove_spawns);
224 
225 static struct crypto_larval *crypto_alloc_test_larval(struct crypto_alg *alg)
226 {
227 	struct crypto_larval *larval;
228 
229 	if (!IS_ENABLED(CONFIG_CRYPTO_MANAGER))
230 		return NULL;
231 
232 	larval = crypto_larval_alloc(alg->cra_name,
233 				     alg->cra_flags | CRYPTO_ALG_TESTED, 0);
234 	if (IS_ERR(larval))
235 		return larval;
236 
237 	larval->adult = crypto_mod_get(alg);
238 	if (!larval->adult) {
239 		kfree(larval);
240 		return ERR_PTR(-ENOENT);
241 	}
242 
243 	refcount_set(&larval->alg.cra_refcnt, 1);
244 	memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
245 	       CRYPTO_MAX_ALG_NAME);
246 	larval->alg.cra_priority = alg->cra_priority;
247 
248 	return larval;
249 }
250 
251 static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
252 {
253 	struct crypto_alg *q;
254 	struct crypto_larval *larval;
255 	int ret = -EAGAIN;
256 
257 	if (crypto_is_dead(alg))
258 		goto err;
259 
260 	INIT_LIST_HEAD(&alg->cra_users);
261 
262 	/* No cheating! */
263 	alg->cra_flags &= ~CRYPTO_ALG_TESTED;
264 
265 	ret = -EEXIST;
266 
267 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
268 		if (q == alg)
269 			goto err;
270 
271 		if (crypto_is_moribund(q))
272 			continue;
273 
274 		if (crypto_is_larval(q)) {
275 			if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
276 				goto err;
277 			continue;
278 		}
279 
280 		if (!strcmp(q->cra_driver_name, alg->cra_name) ||
281 		    !strcmp(q->cra_name, alg->cra_driver_name))
282 			goto err;
283 	}
284 
285 	larval = crypto_alloc_test_larval(alg);
286 	if (IS_ERR(larval))
287 		goto out;
288 
289 	list_add(&alg->cra_list, &crypto_alg_list);
290 
291 	if (larval)
292 		list_add(&larval->alg.cra_list, &crypto_alg_list);
293 	else
294 		alg->cra_flags |= CRYPTO_ALG_TESTED;
295 
296 	crypto_stats_init(alg);
297 
298 out:
299 	return larval;
300 
301 err:
302 	larval = ERR_PTR(ret);
303 	goto out;
304 }
305 
306 void crypto_alg_tested(const char *name, int err)
307 {
308 	struct crypto_larval *test;
309 	struct crypto_alg *alg;
310 	struct crypto_alg *q;
311 	LIST_HEAD(list);
312 	bool best;
313 
314 	down_write(&crypto_alg_sem);
315 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
316 		if (crypto_is_moribund(q) || !crypto_is_larval(q))
317 			continue;
318 
319 		test = (struct crypto_larval *)q;
320 
321 		if (!strcmp(q->cra_driver_name, name))
322 			goto found;
323 	}
324 
325 	pr_err("alg: Unexpected test result for %s: %d\n", name, err);
326 	goto unlock;
327 
328 found:
329 	q->cra_flags |= CRYPTO_ALG_DEAD;
330 	alg = test->adult;
331 
332 	if (list_empty(&alg->cra_list))
333 		goto complete;
334 
335 	if (err == -ECANCELED)
336 		alg->cra_flags |= CRYPTO_ALG_FIPS_INTERNAL;
337 	else if (err)
338 		goto complete;
339 	else
340 		alg->cra_flags &= ~CRYPTO_ALG_FIPS_INTERNAL;
341 
342 	alg->cra_flags |= CRYPTO_ALG_TESTED;
343 
344 	/* Only satisfy larval waiters if we are the best. */
345 	best = true;
346 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
347 		if (crypto_is_moribund(q) || !crypto_is_larval(q))
348 			continue;
349 
350 		if (strcmp(alg->cra_name, q->cra_name))
351 			continue;
352 
353 		if (q->cra_priority > alg->cra_priority) {
354 			best = false;
355 			break;
356 		}
357 	}
358 
359 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
360 		if (q == alg)
361 			continue;
362 
363 		if (crypto_is_moribund(q))
364 			continue;
365 
366 		if (crypto_is_larval(q)) {
367 			struct crypto_larval *larval = (void *)q;
368 
369 			/*
370 			 * Check to see if either our generic name or
371 			 * specific name can satisfy the name requested
372 			 * by the larval entry q.
373 			 */
374 			if (strcmp(alg->cra_name, q->cra_name) &&
375 			    strcmp(alg->cra_driver_name, q->cra_name))
376 				continue;
377 
378 			if (larval->adult)
379 				continue;
380 			if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
381 				continue;
382 
383 			if (best && crypto_mod_get(alg))
384 				larval->adult = alg;
385 			else
386 				larval->adult = ERR_PTR(-EAGAIN);
387 
388 			continue;
389 		}
390 
391 		if (strcmp(alg->cra_name, q->cra_name))
392 			continue;
393 
394 		if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
395 		    q->cra_priority > alg->cra_priority)
396 			continue;
397 
398 		crypto_remove_spawns(q, &list, alg);
399 	}
400 
401 complete:
402 	complete_all(&test->completion);
403 
404 unlock:
405 	up_write(&crypto_alg_sem);
406 
407 	crypto_remove_final(&list);
408 }
409 EXPORT_SYMBOL_GPL(crypto_alg_tested);
410 
411 void crypto_remove_final(struct list_head *list)
412 {
413 	struct crypto_alg *alg;
414 	struct crypto_alg *n;
415 
416 	list_for_each_entry_safe(alg, n, list, cra_list) {
417 		list_del_init(&alg->cra_list);
418 		crypto_alg_put(alg);
419 	}
420 }
421 EXPORT_SYMBOL_GPL(crypto_remove_final);
422 
423 int crypto_register_alg(struct crypto_alg *alg)
424 {
425 	struct crypto_larval *larval;
426 	bool test_started;
427 	int err;
428 
429 	alg->cra_flags &= ~CRYPTO_ALG_DEAD;
430 	err = crypto_check_alg(alg);
431 	if (err)
432 		return err;
433 
434 	down_write(&crypto_alg_sem);
435 	larval = __crypto_register_alg(alg);
436 	test_started = static_key_enabled(&crypto_boot_test_finished);
437 	if (!IS_ERR_OR_NULL(larval))
438 		larval->test_started = test_started;
439 	up_write(&crypto_alg_sem);
440 
441 	if (IS_ERR_OR_NULL(larval))
442 		return PTR_ERR(larval);
443 
444 	if (test_started)
445 		crypto_wait_for_test(larval);
446 	return 0;
447 }
448 EXPORT_SYMBOL_GPL(crypto_register_alg);
449 
450 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
451 {
452 	if (unlikely(list_empty(&alg->cra_list)))
453 		return -ENOENT;
454 
455 	alg->cra_flags |= CRYPTO_ALG_DEAD;
456 
457 	list_del_init(&alg->cra_list);
458 	crypto_remove_spawns(alg, list, NULL);
459 
460 	return 0;
461 }
462 
463 void crypto_unregister_alg(struct crypto_alg *alg)
464 {
465 	int ret;
466 	LIST_HEAD(list);
467 
468 	down_write(&crypto_alg_sem);
469 	ret = crypto_remove_alg(alg, &list);
470 	up_write(&crypto_alg_sem);
471 
472 	if (WARN(ret, "Algorithm %s is not registered", alg->cra_driver_name))
473 		return;
474 
475 	BUG_ON(refcount_read(&alg->cra_refcnt) != 1);
476 	if (alg->cra_destroy)
477 		alg->cra_destroy(alg);
478 
479 	crypto_remove_final(&list);
480 }
481 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
482 
483 int crypto_register_algs(struct crypto_alg *algs, int count)
484 {
485 	int i, ret;
486 
487 	for (i = 0; i < count; i++) {
488 		ret = crypto_register_alg(&algs[i]);
489 		if (ret)
490 			goto err;
491 	}
492 
493 	return 0;
494 
495 err:
496 	for (--i; i >= 0; --i)
497 		crypto_unregister_alg(&algs[i]);
498 
499 	return ret;
500 }
501 EXPORT_SYMBOL_GPL(crypto_register_algs);
502 
503 void crypto_unregister_algs(struct crypto_alg *algs, int count)
504 {
505 	int i;
506 
507 	for (i = 0; i < count; i++)
508 		crypto_unregister_alg(&algs[i]);
509 }
510 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
511 
512 int crypto_register_template(struct crypto_template *tmpl)
513 {
514 	struct crypto_template *q;
515 	int err = -EEXIST;
516 
517 	down_write(&crypto_alg_sem);
518 
519 	crypto_check_module_sig(tmpl->module);
520 
521 	list_for_each_entry(q, &crypto_template_list, list) {
522 		if (q == tmpl)
523 			goto out;
524 	}
525 
526 	list_add(&tmpl->list, &crypto_template_list);
527 	err = 0;
528 out:
529 	up_write(&crypto_alg_sem);
530 	return err;
531 }
532 EXPORT_SYMBOL_GPL(crypto_register_template);
533 
534 int crypto_register_templates(struct crypto_template *tmpls, int count)
535 {
536 	int i, err;
537 
538 	for (i = 0; i < count; i++) {
539 		err = crypto_register_template(&tmpls[i]);
540 		if (err)
541 			goto out;
542 	}
543 	return 0;
544 
545 out:
546 	for (--i; i >= 0; --i)
547 		crypto_unregister_template(&tmpls[i]);
548 	return err;
549 }
550 EXPORT_SYMBOL_GPL(crypto_register_templates);
551 
552 void crypto_unregister_template(struct crypto_template *tmpl)
553 {
554 	struct crypto_instance *inst;
555 	struct hlist_node *n;
556 	struct hlist_head *list;
557 	LIST_HEAD(users);
558 
559 	down_write(&crypto_alg_sem);
560 
561 	BUG_ON(list_empty(&tmpl->list));
562 	list_del_init(&tmpl->list);
563 
564 	list = &tmpl->instances;
565 	hlist_for_each_entry(inst, list, list) {
566 		int err = crypto_remove_alg(&inst->alg, &users);
567 
568 		BUG_ON(err);
569 	}
570 
571 	up_write(&crypto_alg_sem);
572 
573 	hlist_for_each_entry_safe(inst, n, list, list) {
574 		BUG_ON(refcount_read(&inst->alg.cra_refcnt) != 1);
575 		crypto_free_instance(inst);
576 	}
577 	crypto_remove_final(&users);
578 }
579 EXPORT_SYMBOL_GPL(crypto_unregister_template);
580 
581 void crypto_unregister_templates(struct crypto_template *tmpls, int count)
582 {
583 	int i;
584 
585 	for (i = count - 1; i >= 0; --i)
586 		crypto_unregister_template(&tmpls[i]);
587 }
588 EXPORT_SYMBOL_GPL(crypto_unregister_templates);
589 
590 static struct crypto_template *__crypto_lookup_template(const char *name)
591 {
592 	struct crypto_template *q, *tmpl = NULL;
593 
594 	down_read(&crypto_alg_sem);
595 	list_for_each_entry(q, &crypto_template_list, list) {
596 		if (strcmp(q->name, name))
597 			continue;
598 		if (unlikely(!crypto_tmpl_get(q)))
599 			continue;
600 
601 		tmpl = q;
602 		break;
603 	}
604 	up_read(&crypto_alg_sem);
605 
606 	return tmpl;
607 }
608 
609 struct crypto_template *crypto_lookup_template(const char *name)
610 {
611 	return try_then_request_module(__crypto_lookup_template(name),
612 				       "crypto-%s", name);
613 }
614 EXPORT_SYMBOL_GPL(crypto_lookup_template);
615 
616 int crypto_register_instance(struct crypto_template *tmpl,
617 			     struct crypto_instance *inst)
618 {
619 	struct crypto_larval *larval;
620 	struct crypto_spawn *spawn;
621 	u32 fips_internal = 0;
622 	int err;
623 
624 	err = crypto_check_alg(&inst->alg);
625 	if (err)
626 		return err;
627 
628 	inst->alg.cra_module = tmpl->module;
629 	inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
630 
631 	down_write(&crypto_alg_sem);
632 
633 	larval = ERR_PTR(-EAGAIN);
634 	for (spawn = inst->spawns; spawn;) {
635 		struct crypto_spawn *next;
636 
637 		if (spawn->dead)
638 			goto unlock;
639 
640 		next = spawn->next;
641 		spawn->inst = inst;
642 		spawn->registered = true;
643 
644 		fips_internal |= spawn->alg->cra_flags;
645 
646 		crypto_mod_put(spawn->alg);
647 
648 		spawn = next;
649 	}
650 
651 	inst->alg.cra_flags |= (fips_internal & CRYPTO_ALG_FIPS_INTERNAL);
652 
653 	larval = __crypto_register_alg(&inst->alg);
654 	if (IS_ERR(larval))
655 		goto unlock;
656 	else if (larval)
657 		larval->test_started = true;
658 
659 	hlist_add_head(&inst->list, &tmpl->instances);
660 	inst->tmpl = tmpl;
661 
662 unlock:
663 	up_write(&crypto_alg_sem);
664 
665 	err = PTR_ERR(larval);
666 	if (IS_ERR_OR_NULL(larval))
667 		goto err;
668 
669 	crypto_wait_for_test(larval);
670 	err = 0;
671 
672 err:
673 	return err;
674 }
675 EXPORT_SYMBOL_GPL(crypto_register_instance);
676 
677 void crypto_unregister_instance(struct crypto_instance *inst)
678 {
679 	LIST_HEAD(list);
680 
681 	down_write(&crypto_alg_sem);
682 
683 	crypto_remove_spawns(&inst->alg, &list, NULL);
684 	crypto_remove_instance(inst, &list);
685 
686 	up_write(&crypto_alg_sem);
687 
688 	crypto_remove_final(&list);
689 }
690 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
691 
692 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
693 		      const char *name, u32 type, u32 mask)
694 {
695 	struct crypto_alg *alg;
696 	int err = -EAGAIN;
697 
698 	if (WARN_ON_ONCE(inst == NULL))
699 		return -EINVAL;
700 
701 	/* Allow the result of crypto_attr_alg_name() to be passed directly */
702 	if (IS_ERR(name))
703 		return PTR_ERR(name);
704 
705 	alg = crypto_find_alg(name, spawn->frontend,
706 			      type | CRYPTO_ALG_FIPS_INTERNAL, mask);
707 	if (IS_ERR(alg))
708 		return PTR_ERR(alg);
709 
710 	down_write(&crypto_alg_sem);
711 	if (!crypto_is_moribund(alg)) {
712 		list_add(&spawn->list, &alg->cra_users);
713 		spawn->alg = alg;
714 		spawn->mask = mask;
715 		spawn->next = inst->spawns;
716 		inst->spawns = spawn;
717 		inst->alg.cra_flags |=
718 			(alg->cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
719 		err = 0;
720 	}
721 	up_write(&crypto_alg_sem);
722 	if (err)
723 		crypto_mod_put(alg);
724 	return err;
725 }
726 EXPORT_SYMBOL_GPL(crypto_grab_spawn);
727 
728 void crypto_drop_spawn(struct crypto_spawn *spawn)
729 {
730 	if (!spawn->alg) /* not yet initialized? */
731 		return;
732 
733 	down_write(&crypto_alg_sem);
734 	if (!spawn->dead)
735 		list_del(&spawn->list);
736 	up_write(&crypto_alg_sem);
737 
738 	if (!spawn->registered)
739 		crypto_mod_put(spawn->alg);
740 }
741 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
742 
743 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
744 {
745 	struct crypto_alg *alg = ERR_PTR(-EAGAIN);
746 	struct crypto_alg *target;
747 	bool shoot = false;
748 
749 	down_read(&crypto_alg_sem);
750 	if (!spawn->dead) {
751 		alg = spawn->alg;
752 		if (!crypto_mod_get(alg)) {
753 			target = crypto_alg_get(alg);
754 			shoot = true;
755 			alg = ERR_PTR(-EAGAIN);
756 		}
757 	}
758 	up_read(&crypto_alg_sem);
759 
760 	if (shoot) {
761 		crypto_shoot_alg(target);
762 		crypto_alg_put(target);
763 	}
764 
765 	return alg;
766 }
767 
768 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
769 				    u32 mask)
770 {
771 	struct crypto_alg *alg;
772 	struct crypto_tfm *tfm;
773 
774 	alg = crypto_spawn_alg(spawn);
775 	if (IS_ERR(alg))
776 		return ERR_CAST(alg);
777 
778 	tfm = ERR_PTR(-EINVAL);
779 	if (unlikely((alg->cra_flags ^ type) & mask))
780 		goto out_put_alg;
781 
782 	tfm = __crypto_alloc_tfm(alg, type, mask);
783 	if (IS_ERR(tfm))
784 		goto out_put_alg;
785 
786 	return tfm;
787 
788 out_put_alg:
789 	crypto_mod_put(alg);
790 	return tfm;
791 }
792 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
793 
794 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
795 {
796 	struct crypto_alg *alg;
797 	struct crypto_tfm *tfm;
798 
799 	alg = crypto_spawn_alg(spawn);
800 	if (IS_ERR(alg))
801 		return ERR_CAST(alg);
802 
803 	tfm = crypto_create_tfm(alg, spawn->frontend);
804 	if (IS_ERR(tfm))
805 		goto out_put_alg;
806 
807 	return tfm;
808 
809 out_put_alg:
810 	crypto_mod_put(alg);
811 	return tfm;
812 }
813 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
814 
815 int crypto_register_notifier(struct notifier_block *nb)
816 {
817 	return blocking_notifier_chain_register(&crypto_chain, nb);
818 }
819 EXPORT_SYMBOL_GPL(crypto_register_notifier);
820 
821 int crypto_unregister_notifier(struct notifier_block *nb)
822 {
823 	return blocking_notifier_chain_unregister(&crypto_chain, nb);
824 }
825 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
826 
827 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
828 {
829 	struct rtattr *rta = tb[0];
830 	struct crypto_attr_type *algt;
831 
832 	if (!rta)
833 		return ERR_PTR(-ENOENT);
834 	if (RTA_PAYLOAD(rta) < sizeof(*algt))
835 		return ERR_PTR(-EINVAL);
836 	if (rta->rta_type != CRYPTOA_TYPE)
837 		return ERR_PTR(-EINVAL);
838 
839 	algt = RTA_DATA(rta);
840 
841 	return algt;
842 }
843 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
844 
845 /**
846  * crypto_check_attr_type() - check algorithm type and compute inherited mask
847  * @tb: the template parameters
848  * @type: the algorithm type the template would be instantiated as
849  * @mask_ret: (output) the mask that should be passed to crypto_grab_*()
850  *	      to restrict the flags of any inner algorithms
851  *
852  * Validate that the algorithm type the user requested is compatible with the
853  * one the template would actually be instantiated as.  E.g., if the user is
854  * doing crypto_alloc_shash("cbc(aes)", ...), this would return an error because
855  * the "cbc" template creates an "skcipher" algorithm, not an "shash" algorithm.
856  *
857  * Also compute the mask to use to restrict the flags of any inner algorithms.
858  *
859  * Return: 0 on success; -errno on failure
860  */
861 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret)
862 {
863 	struct crypto_attr_type *algt;
864 
865 	algt = crypto_get_attr_type(tb);
866 	if (IS_ERR(algt))
867 		return PTR_ERR(algt);
868 
869 	if ((algt->type ^ type) & algt->mask)
870 		return -EINVAL;
871 
872 	*mask_ret = crypto_algt_inherited_mask(algt);
873 	return 0;
874 }
875 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
876 
877 const char *crypto_attr_alg_name(struct rtattr *rta)
878 {
879 	struct crypto_attr_alg *alga;
880 
881 	if (!rta)
882 		return ERR_PTR(-ENOENT);
883 	if (RTA_PAYLOAD(rta) < sizeof(*alga))
884 		return ERR_PTR(-EINVAL);
885 	if (rta->rta_type != CRYPTOA_ALG)
886 		return ERR_PTR(-EINVAL);
887 
888 	alga = RTA_DATA(rta);
889 	alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
890 
891 	return alga->name;
892 }
893 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
894 
895 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
896 			struct crypto_alg *alg)
897 {
898 	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
899 		     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
900 		return -ENAMETOOLONG;
901 
902 	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
903 		     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
904 		return -ENAMETOOLONG;
905 
906 	return 0;
907 }
908 EXPORT_SYMBOL_GPL(crypto_inst_setname);
909 
910 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
911 {
912 	INIT_LIST_HEAD(&queue->list);
913 	queue->backlog = &queue->list;
914 	queue->qlen = 0;
915 	queue->max_qlen = max_qlen;
916 }
917 EXPORT_SYMBOL_GPL(crypto_init_queue);
918 
919 int crypto_enqueue_request(struct crypto_queue *queue,
920 			   struct crypto_async_request *request)
921 {
922 	int err = -EINPROGRESS;
923 
924 	if (unlikely(queue->qlen >= queue->max_qlen)) {
925 		if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
926 			err = -ENOSPC;
927 			goto out;
928 		}
929 		err = -EBUSY;
930 		if (queue->backlog == &queue->list)
931 			queue->backlog = &request->list;
932 	}
933 
934 	queue->qlen++;
935 	list_add_tail(&request->list, &queue->list);
936 
937 out:
938 	return err;
939 }
940 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
941 
942 void crypto_enqueue_request_head(struct crypto_queue *queue,
943 				 struct crypto_async_request *request)
944 {
945 	queue->qlen++;
946 	list_add(&request->list, &queue->list);
947 }
948 EXPORT_SYMBOL_GPL(crypto_enqueue_request_head);
949 
950 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
951 {
952 	struct list_head *request;
953 
954 	if (unlikely(!queue->qlen))
955 		return NULL;
956 
957 	queue->qlen--;
958 
959 	if (queue->backlog != &queue->list)
960 		queue->backlog = queue->backlog->next;
961 
962 	request = queue->list.next;
963 	list_del(request);
964 
965 	return list_entry(request, struct crypto_async_request, list);
966 }
967 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
968 
969 static inline void crypto_inc_byte(u8 *a, unsigned int size)
970 {
971 	u8 *b = (a + size);
972 	u8 c;
973 
974 	for (; size; size--) {
975 		c = *--b + 1;
976 		*b = c;
977 		if (c)
978 			break;
979 	}
980 }
981 
982 void crypto_inc(u8 *a, unsigned int size)
983 {
984 	__be32 *b = (__be32 *)(a + size);
985 	u32 c;
986 
987 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
988 	    IS_ALIGNED((unsigned long)b, __alignof__(*b)))
989 		for (; size >= 4; size -= 4) {
990 			c = be32_to_cpu(*--b) + 1;
991 			*b = cpu_to_be32(c);
992 			if (likely(c))
993 				return;
994 		}
995 
996 	crypto_inc_byte(a, size);
997 }
998 EXPORT_SYMBOL_GPL(crypto_inc);
999 
1000 unsigned int crypto_alg_extsize(struct crypto_alg *alg)
1001 {
1002 	return alg->cra_ctxsize +
1003 	       (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
1004 }
1005 EXPORT_SYMBOL_GPL(crypto_alg_extsize);
1006 
1007 int crypto_type_has_alg(const char *name, const struct crypto_type *frontend,
1008 			u32 type, u32 mask)
1009 {
1010 	int ret = 0;
1011 	struct crypto_alg *alg = crypto_find_alg(name, frontend, type, mask);
1012 
1013 	if (!IS_ERR(alg)) {
1014 		crypto_mod_put(alg);
1015 		ret = 1;
1016 	}
1017 
1018 	return ret;
1019 }
1020 EXPORT_SYMBOL_GPL(crypto_type_has_alg);
1021 
1022 #ifdef CONFIG_CRYPTO_STATS
1023 void crypto_stats_init(struct crypto_alg *alg)
1024 {
1025 	memset(&alg->stats, 0, sizeof(alg->stats));
1026 }
1027 EXPORT_SYMBOL_GPL(crypto_stats_init);
1028 
1029 void crypto_stats_get(struct crypto_alg *alg)
1030 {
1031 	crypto_alg_get(alg);
1032 }
1033 EXPORT_SYMBOL_GPL(crypto_stats_get);
1034 
1035 void crypto_stats_aead_encrypt(unsigned int cryptlen, struct crypto_alg *alg,
1036 			       int ret)
1037 {
1038 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1039 		atomic64_inc(&alg->stats.aead.err_cnt);
1040 	} else {
1041 		atomic64_inc(&alg->stats.aead.encrypt_cnt);
1042 		atomic64_add(cryptlen, &alg->stats.aead.encrypt_tlen);
1043 	}
1044 	crypto_alg_put(alg);
1045 }
1046 EXPORT_SYMBOL_GPL(crypto_stats_aead_encrypt);
1047 
1048 void crypto_stats_aead_decrypt(unsigned int cryptlen, struct crypto_alg *alg,
1049 			       int ret)
1050 {
1051 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1052 		atomic64_inc(&alg->stats.aead.err_cnt);
1053 	} else {
1054 		atomic64_inc(&alg->stats.aead.decrypt_cnt);
1055 		atomic64_add(cryptlen, &alg->stats.aead.decrypt_tlen);
1056 	}
1057 	crypto_alg_put(alg);
1058 }
1059 EXPORT_SYMBOL_GPL(crypto_stats_aead_decrypt);
1060 
1061 void crypto_stats_akcipher_encrypt(unsigned int src_len, int ret,
1062 				   struct crypto_alg *alg)
1063 {
1064 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1065 		atomic64_inc(&alg->stats.akcipher.err_cnt);
1066 	} else {
1067 		atomic64_inc(&alg->stats.akcipher.encrypt_cnt);
1068 		atomic64_add(src_len, &alg->stats.akcipher.encrypt_tlen);
1069 	}
1070 	crypto_alg_put(alg);
1071 }
1072 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_encrypt);
1073 
1074 void crypto_stats_akcipher_decrypt(unsigned int src_len, int ret,
1075 				   struct crypto_alg *alg)
1076 {
1077 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1078 		atomic64_inc(&alg->stats.akcipher.err_cnt);
1079 	} else {
1080 		atomic64_inc(&alg->stats.akcipher.decrypt_cnt);
1081 		atomic64_add(src_len, &alg->stats.akcipher.decrypt_tlen);
1082 	}
1083 	crypto_alg_put(alg);
1084 }
1085 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_decrypt);
1086 
1087 void crypto_stats_akcipher_sign(int ret, struct crypto_alg *alg)
1088 {
1089 	if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1090 		atomic64_inc(&alg->stats.akcipher.err_cnt);
1091 	else
1092 		atomic64_inc(&alg->stats.akcipher.sign_cnt);
1093 	crypto_alg_put(alg);
1094 }
1095 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_sign);
1096 
1097 void crypto_stats_akcipher_verify(int ret, struct crypto_alg *alg)
1098 {
1099 	if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1100 		atomic64_inc(&alg->stats.akcipher.err_cnt);
1101 	else
1102 		atomic64_inc(&alg->stats.akcipher.verify_cnt);
1103 	crypto_alg_put(alg);
1104 }
1105 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_verify);
1106 
1107 void crypto_stats_compress(unsigned int slen, int ret, struct crypto_alg *alg)
1108 {
1109 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1110 		atomic64_inc(&alg->stats.compress.err_cnt);
1111 	} else {
1112 		atomic64_inc(&alg->stats.compress.compress_cnt);
1113 		atomic64_add(slen, &alg->stats.compress.compress_tlen);
1114 	}
1115 	crypto_alg_put(alg);
1116 }
1117 EXPORT_SYMBOL_GPL(crypto_stats_compress);
1118 
1119 void crypto_stats_decompress(unsigned int slen, int ret, struct crypto_alg *alg)
1120 {
1121 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1122 		atomic64_inc(&alg->stats.compress.err_cnt);
1123 	} else {
1124 		atomic64_inc(&alg->stats.compress.decompress_cnt);
1125 		atomic64_add(slen, &alg->stats.compress.decompress_tlen);
1126 	}
1127 	crypto_alg_put(alg);
1128 }
1129 EXPORT_SYMBOL_GPL(crypto_stats_decompress);
1130 
1131 void crypto_stats_ahash_update(unsigned int nbytes, int ret,
1132 			       struct crypto_alg *alg)
1133 {
1134 	if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1135 		atomic64_inc(&alg->stats.hash.err_cnt);
1136 	else
1137 		atomic64_add(nbytes, &alg->stats.hash.hash_tlen);
1138 	crypto_alg_put(alg);
1139 }
1140 EXPORT_SYMBOL_GPL(crypto_stats_ahash_update);
1141 
1142 void crypto_stats_ahash_final(unsigned int nbytes, int ret,
1143 			      struct crypto_alg *alg)
1144 {
1145 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1146 		atomic64_inc(&alg->stats.hash.err_cnt);
1147 	} else {
1148 		atomic64_inc(&alg->stats.hash.hash_cnt);
1149 		atomic64_add(nbytes, &alg->stats.hash.hash_tlen);
1150 	}
1151 	crypto_alg_put(alg);
1152 }
1153 EXPORT_SYMBOL_GPL(crypto_stats_ahash_final);
1154 
1155 void crypto_stats_kpp_set_secret(struct crypto_alg *alg, int ret)
1156 {
1157 	if (ret)
1158 		atomic64_inc(&alg->stats.kpp.err_cnt);
1159 	else
1160 		atomic64_inc(&alg->stats.kpp.setsecret_cnt);
1161 	crypto_alg_put(alg);
1162 }
1163 EXPORT_SYMBOL_GPL(crypto_stats_kpp_set_secret);
1164 
1165 void crypto_stats_kpp_generate_public_key(struct crypto_alg *alg, int ret)
1166 {
1167 	if (ret)
1168 		atomic64_inc(&alg->stats.kpp.err_cnt);
1169 	else
1170 		atomic64_inc(&alg->stats.kpp.generate_public_key_cnt);
1171 	crypto_alg_put(alg);
1172 }
1173 EXPORT_SYMBOL_GPL(crypto_stats_kpp_generate_public_key);
1174 
1175 void crypto_stats_kpp_compute_shared_secret(struct crypto_alg *alg, int ret)
1176 {
1177 	if (ret)
1178 		atomic64_inc(&alg->stats.kpp.err_cnt);
1179 	else
1180 		atomic64_inc(&alg->stats.kpp.compute_shared_secret_cnt);
1181 	crypto_alg_put(alg);
1182 }
1183 EXPORT_SYMBOL_GPL(crypto_stats_kpp_compute_shared_secret);
1184 
1185 void crypto_stats_rng_seed(struct crypto_alg *alg, int ret)
1186 {
1187 	if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1188 		atomic64_inc(&alg->stats.rng.err_cnt);
1189 	else
1190 		atomic64_inc(&alg->stats.rng.seed_cnt);
1191 	crypto_alg_put(alg);
1192 }
1193 EXPORT_SYMBOL_GPL(crypto_stats_rng_seed);
1194 
1195 void crypto_stats_rng_generate(struct crypto_alg *alg, unsigned int dlen,
1196 			       int ret)
1197 {
1198 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1199 		atomic64_inc(&alg->stats.rng.err_cnt);
1200 	} else {
1201 		atomic64_inc(&alg->stats.rng.generate_cnt);
1202 		atomic64_add(dlen, &alg->stats.rng.generate_tlen);
1203 	}
1204 	crypto_alg_put(alg);
1205 }
1206 EXPORT_SYMBOL_GPL(crypto_stats_rng_generate);
1207 
1208 void crypto_stats_skcipher_encrypt(unsigned int cryptlen, int ret,
1209 				   struct crypto_alg *alg)
1210 {
1211 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1212 		atomic64_inc(&alg->stats.cipher.err_cnt);
1213 	} else {
1214 		atomic64_inc(&alg->stats.cipher.encrypt_cnt);
1215 		atomic64_add(cryptlen, &alg->stats.cipher.encrypt_tlen);
1216 	}
1217 	crypto_alg_put(alg);
1218 }
1219 EXPORT_SYMBOL_GPL(crypto_stats_skcipher_encrypt);
1220 
1221 void crypto_stats_skcipher_decrypt(unsigned int cryptlen, int ret,
1222 				   struct crypto_alg *alg)
1223 {
1224 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1225 		atomic64_inc(&alg->stats.cipher.err_cnt);
1226 	} else {
1227 		atomic64_inc(&alg->stats.cipher.decrypt_cnt);
1228 		atomic64_add(cryptlen, &alg->stats.cipher.decrypt_tlen);
1229 	}
1230 	crypto_alg_put(alg);
1231 }
1232 EXPORT_SYMBOL_GPL(crypto_stats_skcipher_decrypt);
1233 #endif
1234 
1235 static void __init crypto_start_tests(void)
1236 {
1237 	for (;;) {
1238 		struct crypto_larval *larval = NULL;
1239 		struct crypto_alg *q;
1240 
1241 		down_write(&crypto_alg_sem);
1242 
1243 		list_for_each_entry(q, &crypto_alg_list, cra_list) {
1244 			struct crypto_larval *l;
1245 
1246 			if (!crypto_is_larval(q))
1247 				continue;
1248 
1249 			l = (void *)q;
1250 
1251 			if (!crypto_is_test_larval(l))
1252 				continue;
1253 
1254 			if (l->test_started)
1255 				continue;
1256 
1257 			l->test_started = true;
1258 			larval = l;
1259 			break;
1260 		}
1261 
1262 		up_write(&crypto_alg_sem);
1263 
1264 		if (!larval)
1265 			break;
1266 
1267 		crypto_wait_for_test(larval);
1268 	}
1269 
1270 	static_branch_enable(&crypto_boot_test_finished);
1271 }
1272 
1273 static int __init crypto_algapi_init(void)
1274 {
1275 	crypto_init_proc();
1276 	crypto_start_tests();
1277 	return 0;
1278 }
1279 
1280 static void __exit crypto_algapi_exit(void)
1281 {
1282 	crypto_exit_proc();
1283 }
1284 
1285 /*
1286  * We run this at late_initcall so that all the built-in algorithms
1287  * have had a chance to register themselves first.
1288  */
1289 late_initcall(crypto_algapi_init);
1290 module_exit(crypto_algapi_exit);
1291 
1292 MODULE_LICENSE("GPL");
1293 MODULE_DESCRIPTION("Cryptographic algorithms API");
1294 MODULE_SOFTDEP("pre: cryptomgr");
1295