xref: /openbmc/linux/crypto/algapi.c (revision f7af616c)
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 <linux/err.h>
10 #include <linux/errno.h>
11 #include <linux/fips.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/list.h>
15 #include <linux/module.h>
16 #include <linux/rtnetlink.h>
17 #include <linux/slab.h>
18 #include <linux/string.h>
19 
20 #include "internal.h"
21 
22 static LIST_HEAD(crypto_template_list);
23 
24 static inline void crypto_check_module_sig(struct module *mod)
25 {
26 	if (fips_enabled && mod && !module_sig_ok(mod))
27 		panic("Module %s signature verification failed in FIPS mode\n",
28 		      module_name(mod));
29 }
30 
31 static int crypto_check_alg(struct crypto_alg *alg)
32 {
33 	crypto_check_module_sig(alg->cra_module);
34 
35 	if (!alg->cra_name[0] || !alg->cra_driver_name[0])
36 		return -EINVAL;
37 
38 	if (alg->cra_alignmask & (alg->cra_alignmask + 1))
39 		return -EINVAL;
40 
41 	/* General maximums for all algs. */
42 	if (alg->cra_alignmask > MAX_ALGAPI_ALIGNMASK)
43 		return -EINVAL;
44 
45 	if (alg->cra_blocksize > MAX_ALGAPI_BLOCKSIZE)
46 		return -EINVAL;
47 
48 	/* Lower maximums for specific alg types. */
49 	if (!alg->cra_type && (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
50 			       CRYPTO_ALG_TYPE_CIPHER) {
51 		if (alg->cra_alignmask > MAX_CIPHER_ALIGNMASK)
52 			return -EINVAL;
53 
54 		if (alg->cra_blocksize > MAX_CIPHER_BLOCKSIZE)
55 			return -EINVAL;
56 	}
57 
58 	if (alg->cra_priority < 0)
59 		return -EINVAL;
60 
61 	refcount_set(&alg->cra_refcnt, 1);
62 
63 	return 0;
64 }
65 
66 static void crypto_free_instance(struct crypto_instance *inst)
67 {
68 	inst->alg.cra_type->free(inst);
69 }
70 
71 static void crypto_destroy_instance(struct crypto_alg *alg)
72 {
73 	struct crypto_instance *inst = (void *)alg;
74 	struct crypto_template *tmpl = inst->tmpl;
75 
76 	crypto_free_instance(inst);
77 	crypto_tmpl_put(tmpl);
78 }
79 
80 /*
81  * This function adds a spawn to the list secondary_spawns which
82  * will be used at the end of crypto_remove_spawns to unregister
83  * instances, unless the spawn happens to be one that is depended
84  * on by the new algorithm (nalg in crypto_remove_spawns).
85  *
86  * This function is also responsible for resurrecting any algorithms
87  * in the dependency chain of nalg by unsetting n->dead.
88  */
89 static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
90 					    struct list_head *stack,
91 					    struct list_head *top,
92 					    struct list_head *secondary_spawns)
93 {
94 	struct crypto_spawn *spawn, *n;
95 
96 	spawn = list_first_entry_or_null(stack, struct crypto_spawn, list);
97 	if (!spawn)
98 		return NULL;
99 
100 	n = list_prev_entry(spawn, list);
101 	list_move(&spawn->list, secondary_spawns);
102 
103 	if (list_is_last(&n->list, stack))
104 		return top;
105 
106 	n = list_next_entry(n, list);
107 	if (!spawn->dead)
108 		n->dead = false;
109 
110 	return &n->inst->alg.cra_users;
111 }
112 
113 static void crypto_remove_instance(struct crypto_instance *inst,
114 				   struct list_head *list)
115 {
116 	struct crypto_template *tmpl = inst->tmpl;
117 
118 	if (crypto_is_dead(&inst->alg))
119 		return;
120 
121 	inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
122 
123 	if (!tmpl || !crypto_tmpl_get(tmpl))
124 		return;
125 
126 	list_move(&inst->alg.cra_list, list);
127 	hlist_del(&inst->list);
128 	inst->alg.cra_destroy = crypto_destroy_instance;
129 
130 	BUG_ON(!list_empty(&inst->alg.cra_users));
131 }
132 
133 /*
134  * Given an algorithm alg, remove all algorithms that depend on it
135  * through spawns.  If nalg is not null, then exempt any algorithms
136  * that is depended on by nalg.  This is useful when nalg itself
137  * depends on alg.
138  */
139 void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
140 			  struct crypto_alg *nalg)
141 {
142 	u32 new_type = (nalg ?: alg)->cra_flags;
143 	struct crypto_spawn *spawn, *n;
144 	LIST_HEAD(secondary_spawns);
145 	struct list_head *spawns;
146 	LIST_HEAD(stack);
147 	LIST_HEAD(top);
148 
149 	spawns = &alg->cra_users;
150 	list_for_each_entry_safe(spawn, n, spawns, list) {
151 		if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
152 			continue;
153 
154 		list_move(&spawn->list, &top);
155 	}
156 
157 	/*
158 	 * Perform a depth-first walk starting from alg through
159 	 * the cra_users tree.  The list stack records the path
160 	 * from alg to the current spawn.
161 	 */
162 	spawns = &top;
163 	do {
164 		while (!list_empty(spawns)) {
165 			struct crypto_instance *inst;
166 
167 			spawn = list_first_entry(spawns, struct crypto_spawn,
168 						 list);
169 			inst = spawn->inst;
170 
171 			list_move(&spawn->list, &stack);
172 			spawn->dead = !spawn->registered || &inst->alg != nalg;
173 
174 			if (!spawn->registered)
175 				break;
176 
177 			BUG_ON(&inst->alg == alg);
178 
179 			if (&inst->alg == nalg)
180 				break;
181 
182 			spawns = &inst->alg.cra_users;
183 
184 			/*
185 			 * Even if spawn->registered is true, the
186 			 * instance itself may still be unregistered.
187 			 * This is because it may have failed during
188 			 * registration.  Therefore we still need to
189 			 * make the following test.
190 			 *
191 			 * We may encounter an unregistered instance here, since
192 			 * an instance's spawns are set up prior to the instance
193 			 * being registered.  An unregistered instance will have
194 			 * NULL ->cra_users.next, since ->cra_users isn't
195 			 * properly initialized until registration.  But an
196 			 * unregistered instance cannot have any users, so treat
197 			 * it the same as ->cra_users being empty.
198 			 */
199 			if (spawns->next == NULL)
200 				break;
201 		}
202 	} while ((spawns = crypto_more_spawns(alg, &stack, &top,
203 					      &secondary_spawns)));
204 
205 	/*
206 	 * Remove all instances that are marked as dead.  Also
207 	 * complete the resurrection of the others by moving them
208 	 * back to the cra_users list.
209 	 */
210 	list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
211 		if (!spawn->dead)
212 			list_move(&spawn->list, &spawn->alg->cra_users);
213 		else if (spawn->registered)
214 			crypto_remove_instance(spawn->inst, list);
215 	}
216 }
217 EXPORT_SYMBOL_GPL(crypto_remove_spawns);
218 
219 static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
220 {
221 	struct crypto_alg *q;
222 	struct crypto_larval *larval;
223 	int ret = -EAGAIN;
224 
225 	if (crypto_is_dead(alg))
226 		goto err;
227 
228 	INIT_LIST_HEAD(&alg->cra_users);
229 
230 	/* No cheating! */
231 	alg->cra_flags &= ~CRYPTO_ALG_TESTED;
232 
233 	ret = -EEXIST;
234 
235 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
236 		if (q == alg)
237 			goto err;
238 
239 		if (crypto_is_moribund(q))
240 			continue;
241 
242 		if (crypto_is_larval(q)) {
243 			if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
244 				goto err;
245 			continue;
246 		}
247 
248 		if (!strcmp(q->cra_driver_name, alg->cra_name) ||
249 		    !strcmp(q->cra_name, alg->cra_driver_name))
250 			goto err;
251 	}
252 
253 	larval = crypto_larval_alloc(alg->cra_name,
254 				     alg->cra_flags | CRYPTO_ALG_TESTED, 0);
255 	if (IS_ERR(larval))
256 		goto out;
257 
258 	ret = -ENOENT;
259 	larval->adult = crypto_mod_get(alg);
260 	if (!larval->adult)
261 		goto free_larval;
262 
263 	refcount_set(&larval->alg.cra_refcnt, 1);
264 	memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
265 	       CRYPTO_MAX_ALG_NAME);
266 	larval->alg.cra_priority = alg->cra_priority;
267 
268 	list_add(&alg->cra_list, &crypto_alg_list);
269 	list_add(&larval->alg.cra_list, &crypto_alg_list);
270 
271 	crypto_stats_init(alg);
272 
273 out:
274 	return larval;
275 
276 free_larval:
277 	kfree(larval);
278 err:
279 	larval = ERR_PTR(ret);
280 	goto out;
281 }
282 
283 void crypto_alg_tested(const char *name, int err)
284 {
285 	struct crypto_larval *test;
286 	struct crypto_alg *alg;
287 	struct crypto_alg *q;
288 	LIST_HEAD(list);
289 	bool best;
290 
291 	down_write(&crypto_alg_sem);
292 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
293 		if (crypto_is_moribund(q) || !crypto_is_larval(q))
294 			continue;
295 
296 		test = (struct crypto_larval *)q;
297 
298 		if (!strcmp(q->cra_driver_name, name))
299 			goto found;
300 	}
301 
302 	pr_err("alg: Unexpected test result for %s: %d\n", name, err);
303 	goto unlock;
304 
305 found:
306 	q->cra_flags |= CRYPTO_ALG_DEAD;
307 	alg = test->adult;
308 	if (err || list_empty(&alg->cra_list))
309 		goto complete;
310 
311 	alg->cra_flags |= CRYPTO_ALG_TESTED;
312 
313 	/* Only satisfy larval waiters if we are the best. */
314 	best = true;
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 		if (strcmp(alg->cra_name, q->cra_name))
320 			continue;
321 
322 		if (q->cra_priority > alg->cra_priority) {
323 			best = false;
324 			break;
325 		}
326 	}
327 
328 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
329 		if (q == alg)
330 			continue;
331 
332 		if (crypto_is_moribund(q))
333 			continue;
334 
335 		if (crypto_is_larval(q)) {
336 			struct crypto_larval *larval = (void *)q;
337 
338 			/*
339 			 * Check to see if either our generic name or
340 			 * specific name can satisfy the name requested
341 			 * by the larval entry q.
342 			 */
343 			if (strcmp(alg->cra_name, q->cra_name) &&
344 			    strcmp(alg->cra_driver_name, q->cra_name))
345 				continue;
346 
347 			if (larval->adult)
348 				continue;
349 			if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
350 				continue;
351 
352 			if (best && crypto_mod_get(alg))
353 				larval->adult = alg;
354 			else
355 				larval->adult = ERR_PTR(-EAGAIN);
356 
357 			continue;
358 		}
359 
360 		if (strcmp(alg->cra_name, q->cra_name))
361 			continue;
362 
363 		if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
364 		    q->cra_priority > alg->cra_priority)
365 			continue;
366 
367 		crypto_remove_spawns(q, &list, alg);
368 	}
369 
370 complete:
371 	complete_all(&test->completion);
372 
373 unlock:
374 	up_write(&crypto_alg_sem);
375 
376 	crypto_remove_final(&list);
377 }
378 EXPORT_SYMBOL_GPL(crypto_alg_tested);
379 
380 void crypto_remove_final(struct list_head *list)
381 {
382 	struct crypto_alg *alg;
383 	struct crypto_alg *n;
384 
385 	list_for_each_entry_safe(alg, n, list, cra_list) {
386 		list_del_init(&alg->cra_list);
387 		crypto_alg_put(alg);
388 	}
389 }
390 EXPORT_SYMBOL_GPL(crypto_remove_final);
391 
392 static void crypto_wait_for_test(struct crypto_larval *larval)
393 {
394 	int err;
395 
396 	err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
397 	if (err != NOTIFY_STOP) {
398 		if (WARN_ON(err != NOTIFY_DONE))
399 			goto out;
400 		crypto_alg_tested(larval->alg.cra_driver_name, 0);
401 	}
402 
403 	err = wait_for_completion_killable(&larval->completion);
404 	WARN_ON(err);
405 	if (!err)
406 		crypto_notify(CRYPTO_MSG_ALG_LOADED, larval);
407 
408 out:
409 	crypto_larval_kill(&larval->alg);
410 }
411 
412 int crypto_register_alg(struct crypto_alg *alg)
413 {
414 	struct crypto_larval *larval;
415 	int err;
416 
417 	alg->cra_flags &= ~CRYPTO_ALG_DEAD;
418 	err = crypto_check_alg(alg);
419 	if (err)
420 		return err;
421 
422 	down_write(&crypto_alg_sem);
423 	larval = __crypto_register_alg(alg);
424 	up_write(&crypto_alg_sem);
425 
426 	if (IS_ERR(larval))
427 		return PTR_ERR(larval);
428 
429 	crypto_wait_for_test(larval);
430 	return 0;
431 }
432 EXPORT_SYMBOL_GPL(crypto_register_alg);
433 
434 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
435 {
436 	if (unlikely(list_empty(&alg->cra_list)))
437 		return -ENOENT;
438 
439 	alg->cra_flags |= CRYPTO_ALG_DEAD;
440 
441 	list_del_init(&alg->cra_list);
442 	crypto_remove_spawns(alg, list, NULL);
443 
444 	return 0;
445 }
446 
447 void crypto_unregister_alg(struct crypto_alg *alg)
448 {
449 	int ret;
450 	LIST_HEAD(list);
451 
452 	down_write(&crypto_alg_sem);
453 	ret = crypto_remove_alg(alg, &list);
454 	up_write(&crypto_alg_sem);
455 
456 	if (WARN(ret, "Algorithm %s is not registered", alg->cra_driver_name))
457 		return;
458 
459 	BUG_ON(refcount_read(&alg->cra_refcnt) != 1);
460 	if (alg->cra_destroy)
461 		alg->cra_destroy(alg);
462 
463 	crypto_remove_final(&list);
464 }
465 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
466 
467 int crypto_register_algs(struct crypto_alg *algs, int count)
468 {
469 	int i, ret;
470 
471 	for (i = 0; i < count; i++) {
472 		ret = crypto_register_alg(&algs[i]);
473 		if (ret)
474 			goto err;
475 	}
476 
477 	return 0;
478 
479 err:
480 	for (--i; i >= 0; --i)
481 		crypto_unregister_alg(&algs[i]);
482 
483 	return ret;
484 }
485 EXPORT_SYMBOL_GPL(crypto_register_algs);
486 
487 void crypto_unregister_algs(struct crypto_alg *algs, int count)
488 {
489 	int i;
490 
491 	for (i = 0; i < count; i++)
492 		crypto_unregister_alg(&algs[i]);
493 }
494 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
495 
496 int crypto_register_template(struct crypto_template *tmpl)
497 {
498 	struct crypto_template *q;
499 	int err = -EEXIST;
500 
501 	down_write(&crypto_alg_sem);
502 
503 	crypto_check_module_sig(tmpl->module);
504 
505 	list_for_each_entry(q, &crypto_template_list, list) {
506 		if (q == tmpl)
507 			goto out;
508 	}
509 
510 	list_add(&tmpl->list, &crypto_template_list);
511 	err = 0;
512 out:
513 	up_write(&crypto_alg_sem);
514 	return err;
515 }
516 EXPORT_SYMBOL_GPL(crypto_register_template);
517 
518 int crypto_register_templates(struct crypto_template *tmpls, int count)
519 {
520 	int i, err;
521 
522 	for (i = 0; i < count; i++) {
523 		err = crypto_register_template(&tmpls[i]);
524 		if (err)
525 			goto out;
526 	}
527 	return 0;
528 
529 out:
530 	for (--i; i >= 0; --i)
531 		crypto_unregister_template(&tmpls[i]);
532 	return err;
533 }
534 EXPORT_SYMBOL_GPL(crypto_register_templates);
535 
536 void crypto_unregister_template(struct crypto_template *tmpl)
537 {
538 	struct crypto_instance *inst;
539 	struct hlist_node *n;
540 	struct hlist_head *list;
541 	LIST_HEAD(users);
542 
543 	down_write(&crypto_alg_sem);
544 
545 	BUG_ON(list_empty(&tmpl->list));
546 	list_del_init(&tmpl->list);
547 
548 	list = &tmpl->instances;
549 	hlist_for_each_entry(inst, list, list) {
550 		int err = crypto_remove_alg(&inst->alg, &users);
551 
552 		BUG_ON(err);
553 	}
554 
555 	up_write(&crypto_alg_sem);
556 
557 	hlist_for_each_entry_safe(inst, n, list, list) {
558 		BUG_ON(refcount_read(&inst->alg.cra_refcnt) != 1);
559 		crypto_free_instance(inst);
560 	}
561 	crypto_remove_final(&users);
562 }
563 EXPORT_SYMBOL_GPL(crypto_unregister_template);
564 
565 void crypto_unregister_templates(struct crypto_template *tmpls, int count)
566 {
567 	int i;
568 
569 	for (i = count - 1; i >= 0; --i)
570 		crypto_unregister_template(&tmpls[i]);
571 }
572 EXPORT_SYMBOL_GPL(crypto_unregister_templates);
573 
574 static struct crypto_template *__crypto_lookup_template(const char *name)
575 {
576 	struct crypto_template *q, *tmpl = NULL;
577 
578 	down_read(&crypto_alg_sem);
579 	list_for_each_entry(q, &crypto_template_list, list) {
580 		if (strcmp(q->name, name))
581 			continue;
582 		if (unlikely(!crypto_tmpl_get(q)))
583 			continue;
584 
585 		tmpl = q;
586 		break;
587 	}
588 	up_read(&crypto_alg_sem);
589 
590 	return tmpl;
591 }
592 
593 struct crypto_template *crypto_lookup_template(const char *name)
594 {
595 	return try_then_request_module(__crypto_lookup_template(name),
596 				       "crypto-%s", name);
597 }
598 EXPORT_SYMBOL_GPL(crypto_lookup_template);
599 
600 int crypto_register_instance(struct crypto_template *tmpl,
601 			     struct crypto_instance *inst)
602 {
603 	struct crypto_larval *larval;
604 	struct crypto_spawn *spawn;
605 	int err;
606 
607 	err = crypto_check_alg(&inst->alg);
608 	if (err)
609 		return err;
610 
611 	inst->alg.cra_module = tmpl->module;
612 	inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
613 
614 	down_write(&crypto_alg_sem);
615 
616 	larval = ERR_PTR(-EAGAIN);
617 	for (spawn = inst->spawns; spawn;) {
618 		struct crypto_spawn *next;
619 
620 		if (spawn->dead)
621 			goto unlock;
622 
623 		next = spawn->next;
624 		spawn->inst = inst;
625 		spawn->registered = true;
626 
627 		crypto_mod_put(spawn->alg);
628 
629 		spawn = next;
630 	}
631 
632 	larval = __crypto_register_alg(&inst->alg);
633 	if (IS_ERR(larval))
634 		goto unlock;
635 
636 	hlist_add_head(&inst->list, &tmpl->instances);
637 	inst->tmpl = tmpl;
638 
639 unlock:
640 	up_write(&crypto_alg_sem);
641 
642 	err = PTR_ERR(larval);
643 	if (IS_ERR(larval))
644 		goto err;
645 
646 	crypto_wait_for_test(larval);
647 	err = 0;
648 
649 err:
650 	return err;
651 }
652 EXPORT_SYMBOL_GPL(crypto_register_instance);
653 
654 void crypto_unregister_instance(struct crypto_instance *inst)
655 {
656 	LIST_HEAD(list);
657 
658 	down_write(&crypto_alg_sem);
659 
660 	crypto_remove_spawns(&inst->alg, &list, NULL);
661 	crypto_remove_instance(inst, &list);
662 
663 	up_write(&crypto_alg_sem);
664 
665 	crypto_remove_final(&list);
666 }
667 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
668 
669 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
670 		      const char *name, u32 type, u32 mask)
671 {
672 	struct crypto_alg *alg;
673 	int err = -EAGAIN;
674 
675 	if (WARN_ON_ONCE(inst == NULL))
676 		return -EINVAL;
677 
678 	/* Allow the result of crypto_attr_alg_name() to be passed directly */
679 	if (IS_ERR(name))
680 		return PTR_ERR(name);
681 
682 	alg = crypto_find_alg(name, spawn->frontend, type, mask);
683 	if (IS_ERR(alg))
684 		return PTR_ERR(alg);
685 
686 	down_write(&crypto_alg_sem);
687 	if (!crypto_is_moribund(alg)) {
688 		list_add(&spawn->list, &alg->cra_users);
689 		spawn->alg = alg;
690 		spawn->mask = mask;
691 		spawn->next = inst->spawns;
692 		inst->spawns = spawn;
693 		inst->alg.cra_flags |=
694 			(alg->cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
695 		err = 0;
696 	}
697 	up_write(&crypto_alg_sem);
698 	if (err)
699 		crypto_mod_put(alg);
700 	return err;
701 }
702 EXPORT_SYMBOL_GPL(crypto_grab_spawn);
703 
704 void crypto_drop_spawn(struct crypto_spawn *spawn)
705 {
706 	if (!spawn->alg) /* not yet initialized? */
707 		return;
708 
709 	down_write(&crypto_alg_sem);
710 	if (!spawn->dead)
711 		list_del(&spawn->list);
712 	up_write(&crypto_alg_sem);
713 
714 	if (!spawn->registered)
715 		crypto_mod_put(spawn->alg);
716 }
717 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
718 
719 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
720 {
721 	struct crypto_alg *alg = ERR_PTR(-EAGAIN);
722 	struct crypto_alg *target;
723 	bool shoot = false;
724 
725 	down_read(&crypto_alg_sem);
726 	if (!spawn->dead) {
727 		alg = spawn->alg;
728 		if (!crypto_mod_get(alg)) {
729 			target = crypto_alg_get(alg);
730 			shoot = true;
731 			alg = ERR_PTR(-EAGAIN);
732 		}
733 	}
734 	up_read(&crypto_alg_sem);
735 
736 	if (shoot) {
737 		crypto_shoot_alg(target);
738 		crypto_alg_put(target);
739 	}
740 
741 	return alg;
742 }
743 
744 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
745 				    u32 mask)
746 {
747 	struct crypto_alg *alg;
748 	struct crypto_tfm *tfm;
749 
750 	alg = crypto_spawn_alg(spawn);
751 	if (IS_ERR(alg))
752 		return ERR_CAST(alg);
753 
754 	tfm = ERR_PTR(-EINVAL);
755 	if (unlikely((alg->cra_flags ^ type) & mask))
756 		goto out_put_alg;
757 
758 	tfm = __crypto_alloc_tfm(alg, type, mask);
759 	if (IS_ERR(tfm))
760 		goto out_put_alg;
761 
762 	return tfm;
763 
764 out_put_alg:
765 	crypto_mod_put(alg);
766 	return tfm;
767 }
768 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
769 
770 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
771 {
772 	struct crypto_alg *alg;
773 	struct crypto_tfm *tfm;
774 
775 	alg = crypto_spawn_alg(spawn);
776 	if (IS_ERR(alg))
777 		return ERR_CAST(alg);
778 
779 	tfm = crypto_create_tfm(alg, spawn->frontend);
780 	if (IS_ERR(tfm))
781 		goto out_put_alg;
782 
783 	return tfm;
784 
785 out_put_alg:
786 	crypto_mod_put(alg);
787 	return tfm;
788 }
789 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
790 
791 int crypto_register_notifier(struct notifier_block *nb)
792 {
793 	return blocking_notifier_chain_register(&crypto_chain, nb);
794 }
795 EXPORT_SYMBOL_GPL(crypto_register_notifier);
796 
797 int crypto_unregister_notifier(struct notifier_block *nb)
798 {
799 	return blocking_notifier_chain_unregister(&crypto_chain, nb);
800 }
801 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
802 
803 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
804 {
805 	struct rtattr *rta = tb[0];
806 	struct crypto_attr_type *algt;
807 
808 	if (!rta)
809 		return ERR_PTR(-ENOENT);
810 	if (RTA_PAYLOAD(rta) < sizeof(*algt))
811 		return ERR_PTR(-EINVAL);
812 	if (rta->rta_type != CRYPTOA_TYPE)
813 		return ERR_PTR(-EINVAL);
814 
815 	algt = RTA_DATA(rta);
816 
817 	return algt;
818 }
819 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
820 
821 /**
822  * crypto_check_attr_type() - check algorithm type and compute inherited mask
823  * @tb: the template parameters
824  * @type: the algorithm type the template would be instantiated as
825  * @mask_ret: (output) the mask that should be passed to crypto_grab_*()
826  *	      to restrict the flags of any inner algorithms
827  *
828  * Validate that the algorithm type the user requested is compatible with the
829  * one the template would actually be instantiated as.  E.g., if the user is
830  * doing crypto_alloc_shash("cbc(aes)", ...), this would return an error because
831  * the "cbc" template creates an "skcipher" algorithm, not an "shash" algorithm.
832  *
833  * Also compute the mask to use to restrict the flags of any inner algorithms.
834  *
835  * Return: 0 on success; -errno on failure
836  */
837 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret)
838 {
839 	struct crypto_attr_type *algt;
840 
841 	algt = crypto_get_attr_type(tb);
842 	if (IS_ERR(algt))
843 		return PTR_ERR(algt);
844 
845 	if ((algt->type ^ type) & algt->mask)
846 		return -EINVAL;
847 
848 	*mask_ret = crypto_algt_inherited_mask(algt);
849 	return 0;
850 }
851 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
852 
853 const char *crypto_attr_alg_name(struct rtattr *rta)
854 {
855 	struct crypto_attr_alg *alga;
856 
857 	if (!rta)
858 		return ERR_PTR(-ENOENT);
859 	if (RTA_PAYLOAD(rta) < sizeof(*alga))
860 		return ERR_PTR(-EINVAL);
861 	if (rta->rta_type != CRYPTOA_ALG)
862 		return ERR_PTR(-EINVAL);
863 
864 	alga = RTA_DATA(rta);
865 	alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
866 
867 	return alga->name;
868 }
869 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
870 
871 int crypto_attr_u32(struct rtattr *rta, u32 *num)
872 {
873 	struct crypto_attr_u32 *nu32;
874 
875 	if (!rta)
876 		return -ENOENT;
877 	if (RTA_PAYLOAD(rta) < sizeof(*nu32))
878 		return -EINVAL;
879 	if (rta->rta_type != CRYPTOA_U32)
880 		return -EINVAL;
881 
882 	nu32 = RTA_DATA(rta);
883 	*num = nu32->num;
884 
885 	return 0;
886 }
887 EXPORT_SYMBOL_GPL(crypto_attr_u32);
888 
889 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
890 			struct crypto_alg *alg)
891 {
892 	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
893 		     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
894 		return -ENAMETOOLONG;
895 
896 	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
897 		     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
898 		return -ENAMETOOLONG;
899 
900 	return 0;
901 }
902 EXPORT_SYMBOL_GPL(crypto_inst_setname);
903 
904 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
905 {
906 	INIT_LIST_HEAD(&queue->list);
907 	queue->backlog = &queue->list;
908 	queue->qlen = 0;
909 	queue->max_qlen = max_qlen;
910 }
911 EXPORT_SYMBOL_GPL(crypto_init_queue);
912 
913 int crypto_enqueue_request(struct crypto_queue *queue,
914 			   struct crypto_async_request *request)
915 {
916 	int err = -EINPROGRESS;
917 
918 	if (unlikely(queue->qlen >= queue->max_qlen)) {
919 		if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
920 			err = -ENOSPC;
921 			goto out;
922 		}
923 		err = -EBUSY;
924 		if (queue->backlog == &queue->list)
925 			queue->backlog = &request->list;
926 	}
927 
928 	queue->qlen++;
929 	list_add_tail(&request->list, &queue->list);
930 
931 out:
932 	return err;
933 }
934 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
935 
936 void crypto_enqueue_request_head(struct crypto_queue *queue,
937 				 struct crypto_async_request *request)
938 {
939 	queue->qlen++;
940 	list_add(&request->list, &queue->list);
941 }
942 EXPORT_SYMBOL_GPL(crypto_enqueue_request_head);
943 
944 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
945 {
946 	struct list_head *request;
947 
948 	if (unlikely(!queue->qlen))
949 		return NULL;
950 
951 	queue->qlen--;
952 
953 	if (queue->backlog != &queue->list)
954 		queue->backlog = queue->backlog->next;
955 
956 	request = queue->list.next;
957 	list_del(request);
958 
959 	return list_entry(request, struct crypto_async_request, list);
960 }
961 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
962 
963 static inline void crypto_inc_byte(u8 *a, unsigned int size)
964 {
965 	u8 *b = (a + size);
966 	u8 c;
967 
968 	for (; size; size--) {
969 		c = *--b + 1;
970 		*b = c;
971 		if (c)
972 			break;
973 	}
974 }
975 
976 void crypto_inc(u8 *a, unsigned int size)
977 {
978 	__be32 *b = (__be32 *)(a + size);
979 	u32 c;
980 
981 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
982 	    IS_ALIGNED((unsigned long)b, __alignof__(*b)))
983 		for (; size >= 4; size -= 4) {
984 			c = be32_to_cpu(*--b) + 1;
985 			*b = cpu_to_be32(c);
986 			if (likely(c))
987 				return;
988 		}
989 
990 	crypto_inc_byte(a, size);
991 }
992 EXPORT_SYMBOL_GPL(crypto_inc);
993 
994 void __crypto_xor(u8 *dst, const u8 *src1, const u8 *src2, unsigned int len)
995 {
996 	int relalign = 0;
997 
998 	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) {
999 		int size = sizeof(unsigned long);
1000 		int d = (((unsigned long)dst ^ (unsigned long)src1) |
1001 			 ((unsigned long)dst ^ (unsigned long)src2)) &
1002 			(size - 1);
1003 
1004 		relalign = d ? 1 << __ffs(d) : size;
1005 
1006 		/*
1007 		 * If we care about alignment, process as many bytes as
1008 		 * needed to advance dst and src to values whose alignments
1009 		 * equal their relative alignment. This will allow us to
1010 		 * process the remainder of the input using optimal strides.
1011 		 */
1012 		while (((unsigned long)dst & (relalign - 1)) && len > 0) {
1013 			*dst++ = *src1++ ^ *src2++;
1014 			len--;
1015 		}
1016 	}
1017 
1018 	while (IS_ENABLED(CONFIG_64BIT) && len >= 8 && !(relalign & 7)) {
1019 		*(u64 *)dst = *(u64 *)src1 ^  *(u64 *)src2;
1020 		dst += 8;
1021 		src1 += 8;
1022 		src2 += 8;
1023 		len -= 8;
1024 	}
1025 
1026 	while (len >= 4 && !(relalign & 3)) {
1027 		*(u32 *)dst = *(u32 *)src1 ^ *(u32 *)src2;
1028 		dst += 4;
1029 		src1 += 4;
1030 		src2 += 4;
1031 		len -= 4;
1032 	}
1033 
1034 	while (len >= 2 && !(relalign & 1)) {
1035 		*(u16 *)dst = *(u16 *)src1 ^ *(u16 *)src2;
1036 		dst += 2;
1037 		src1 += 2;
1038 		src2 += 2;
1039 		len -= 2;
1040 	}
1041 
1042 	while (len--)
1043 		*dst++ = *src1++ ^ *src2++;
1044 }
1045 EXPORT_SYMBOL_GPL(__crypto_xor);
1046 
1047 unsigned int crypto_alg_extsize(struct crypto_alg *alg)
1048 {
1049 	return alg->cra_ctxsize +
1050 	       (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
1051 }
1052 EXPORT_SYMBOL_GPL(crypto_alg_extsize);
1053 
1054 int crypto_type_has_alg(const char *name, const struct crypto_type *frontend,
1055 			u32 type, u32 mask)
1056 {
1057 	int ret = 0;
1058 	struct crypto_alg *alg = crypto_find_alg(name, frontend, type, mask);
1059 
1060 	if (!IS_ERR(alg)) {
1061 		crypto_mod_put(alg);
1062 		ret = 1;
1063 	}
1064 
1065 	return ret;
1066 }
1067 EXPORT_SYMBOL_GPL(crypto_type_has_alg);
1068 
1069 #ifdef CONFIG_CRYPTO_STATS
1070 void crypto_stats_init(struct crypto_alg *alg)
1071 {
1072 	memset(&alg->stats, 0, sizeof(alg->stats));
1073 }
1074 EXPORT_SYMBOL_GPL(crypto_stats_init);
1075 
1076 void crypto_stats_get(struct crypto_alg *alg)
1077 {
1078 	crypto_alg_get(alg);
1079 }
1080 EXPORT_SYMBOL_GPL(crypto_stats_get);
1081 
1082 void crypto_stats_aead_encrypt(unsigned int cryptlen, struct crypto_alg *alg,
1083 			       int ret)
1084 {
1085 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1086 		atomic64_inc(&alg->stats.aead.err_cnt);
1087 	} else {
1088 		atomic64_inc(&alg->stats.aead.encrypt_cnt);
1089 		atomic64_add(cryptlen, &alg->stats.aead.encrypt_tlen);
1090 	}
1091 	crypto_alg_put(alg);
1092 }
1093 EXPORT_SYMBOL_GPL(crypto_stats_aead_encrypt);
1094 
1095 void crypto_stats_aead_decrypt(unsigned int cryptlen, struct crypto_alg *alg,
1096 			       int ret)
1097 {
1098 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1099 		atomic64_inc(&alg->stats.aead.err_cnt);
1100 	} else {
1101 		atomic64_inc(&alg->stats.aead.decrypt_cnt);
1102 		atomic64_add(cryptlen, &alg->stats.aead.decrypt_tlen);
1103 	}
1104 	crypto_alg_put(alg);
1105 }
1106 EXPORT_SYMBOL_GPL(crypto_stats_aead_decrypt);
1107 
1108 void crypto_stats_akcipher_encrypt(unsigned int src_len, int ret,
1109 				   struct crypto_alg *alg)
1110 {
1111 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1112 		atomic64_inc(&alg->stats.akcipher.err_cnt);
1113 	} else {
1114 		atomic64_inc(&alg->stats.akcipher.encrypt_cnt);
1115 		atomic64_add(src_len, &alg->stats.akcipher.encrypt_tlen);
1116 	}
1117 	crypto_alg_put(alg);
1118 }
1119 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_encrypt);
1120 
1121 void crypto_stats_akcipher_decrypt(unsigned int src_len, int ret,
1122 				   struct crypto_alg *alg)
1123 {
1124 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1125 		atomic64_inc(&alg->stats.akcipher.err_cnt);
1126 	} else {
1127 		atomic64_inc(&alg->stats.akcipher.decrypt_cnt);
1128 		atomic64_add(src_len, &alg->stats.akcipher.decrypt_tlen);
1129 	}
1130 	crypto_alg_put(alg);
1131 }
1132 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_decrypt);
1133 
1134 void crypto_stats_akcipher_sign(int ret, struct crypto_alg *alg)
1135 {
1136 	if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1137 		atomic64_inc(&alg->stats.akcipher.err_cnt);
1138 	else
1139 		atomic64_inc(&alg->stats.akcipher.sign_cnt);
1140 	crypto_alg_put(alg);
1141 }
1142 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_sign);
1143 
1144 void crypto_stats_akcipher_verify(int ret, struct crypto_alg *alg)
1145 {
1146 	if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1147 		atomic64_inc(&alg->stats.akcipher.err_cnt);
1148 	else
1149 		atomic64_inc(&alg->stats.akcipher.verify_cnt);
1150 	crypto_alg_put(alg);
1151 }
1152 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_verify);
1153 
1154 void crypto_stats_compress(unsigned int slen, int ret, struct crypto_alg *alg)
1155 {
1156 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1157 		atomic64_inc(&alg->stats.compress.err_cnt);
1158 	} else {
1159 		atomic64_inc(&alg->stats.compress.compress_cnt);
1160 		atomic64_add(slen, &alg->stats.compress.compress_tlen);
1161 	}
1162 	crypto_alg_put(alg);
1163 }
1164 EXPORT_SYMBOL_GPL(crypto_stats_compress);
1165 
1166 void crypto_stats_decompress(unsigned int slen, int ret, struct crypto_alg *alg)
1167 {
1168 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1169 		atomic64_inc(&alg->stats.compress.err_cnt);
1170 	} else {
1171 		atomic64_inc(&alg->stats.compress.decompress_cnt);
1172 		atomic64_add(slen, &alg->stats.compress.decompress_tlen);
1173 	}
1174 	crypto_alg_put(alg);
1175 }
1176 EXPORT_SYMBOL_GPL(crypto_stats_decompress);
1177 
1178 void crypto_stats_ahash_update(unsigned int nbytes, int ret,
1179 			       struct crypto_alg *alg)
1180 {
1181 	if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1182 		atomic64_inc(&alg->stats.hash.err_cnt);
1183 	else
1184 		atomic64_add(nbytes, &alg->stats.hash.hash_tlen);
1185 	crypto_alg_put(alg);
1186 }
1187 EXPORT_SYMBOL_GPL(crypto_stats_ahash_update);
1188 
1189 void crypto_stats_ahash_final(unsigned int nbytes, int ret,
1190 			      struct crypto_alg *alg)
1191 {
1192 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1193 		atomic64_inc(&alg->stats.hash.err_cnt);
1194 	} else {
1195 		atomic64_inc(&alg->stats.hash.hash_cnt);
1196 		atomic64_add(nbytes, &alg->stats.hash.hash_tlen);
1197 	}
1198 	crypto_alg_put(alg);
1199 }
1200 EXPORT_SYMBOL_GPL(crypto_stats_ahash_final);
1201 
1202 void crypto_stats_kpp_set_secret(struct crypto_alg *alg, int ret)
1203 {
1204 	if (ret)
1205 		atomic64_inc(&alg->stats.kpp.err_cnt);
1206 	else
1207 		atomic64_inc(&alg->stats.kpp.setsecret_cnt);
1208 	crypto_alg_put(alg);
1209 }
1210 EXPORT_SYMBOL_GPL(crypto_stats_kpp_set_secret);
1211 
1212 void crypto_stats_kpp_generate_public_key(struct crypto_alg *alg, int ret)
1213 {
1214 	if (ret)
1215 		atomic64_inc(&alg->stats.kpp.err_cnt);
1216 	else
1217 		atomic64_inc(&alg->stats.kpp.generate_public_key_cnt);
1218 	crypto_alg_put(alg);
1219 }
1220 EXPORT_SYMBOL_GPL(crypto_stats_kpp_generate_public_key);
1221 
1222 void crypto_stats_kpp_compute_shared_secret(struct crypto_alg *alg, int ret)
1223 {
1224 	if (ret)
1225 		atomic64_inc(&alg->stats.kpp.err_cnt);
1226 	else
1227 		atomic64_inc(&alg->stats.kpp.compute_shared_secret_cnt);
1228 	crypto_alg_put(alg);
1229 }
1230 EXPORT_SYMBOL_GPL(crypto_stats_kpp_compute_shared_secret);
1231 
1232 void crypto_stats_rng_seed(struct crypto_alg *alg, int ret)
1233 {
1234 	if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1235 		atomic64_inc(&alg->stats.rng.err_cnt);
1236 	else
1237 		atomic64_inc(&alg->stats.rng.seed_cnt);
1238 	crypto_alg_put(alg);
1239 }
1240 EXPORT_SYMBOL_GPL(crypto_stats_rng_seed);
1241 
1242 void crypto_stats_rng_generate(struct crypto_alg *alg, unsigned int dlen,
1243 			       int ret)
1244 {
1245 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1246 		atomic64_inc(&alg->stats.rng.err_cnt);
1247 	} else {
1248 		atomic64_inc(&alg->stats.rng.generate_cnt);
1249 		atomic64_add(dlen, &alg->stats.rng.generate_tlen);
1250 	}
1251 	crypto_alg_put(alg);
1252 }
1253 EXPORT_SYMBOL_GPL(crypto_stats_rng_generate);
1254 
1255 void crypto_stats_skcipher_encrypt(unsigned int cryptlen, int ret,
1256 				   struct crypto_alg *alg)
1257 {
1258 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1259 		atomic64_inc(&alg->stats.cipher.err_cnt);
1260 	} else {
1261 		atomic64_inc(&alg->stats.cipher.encrypt_cnt);
1262 		atomic64_add(cryptlen, &alg->stats.cipher.encrypt_tlen);
1263 	}
1264 	crypto_alg_put(alg);
1265 }
1266 EXPORT_SYMBOL_GPL(crypto_stats_skcipher_encrypt);
1267 
1268 void crypto_stats_skcipher_decrypt(unsigned int cryptlen, int ret,
1269 				   struct crypto_alg *alg)
1270 {
1271 	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1272 		atomic64_inc(&alg->stats.cipher.err_cnt);
1273 	} else {
1274 		atomic64_inc(&alg->stats.cipher.decrypt_cnt);
1275 		atomic64_add(cryptlen, &alg->stats.cipher.decrypt_tlen);
1276 	}
1277 	crypto_alg_put(alg);
1278 }
1279 EXPORT_SYMBOL_GPL(crypto_stats_skcipher_decrypt);
1280 #endif
1281 
1282 static int __init crypto_algapi_init(void)
1283 {
1284 	crypto_init_proc();
1285 	return 0;
1286 }
1287 
1288 static void __exit crypto_algapi_exit(void)
1289 {
1290 	crypto_exit_proc();
1291 }
1292 
1293 module_init(crypto_algapi_init);
1294 module_exit(crypto_algapi_exit);
1295 
1296 MODULE_LICENSE("GPL");
1297 MODULE_DESCRIPTION("Cryptographic algorithms API");
1298