xref: /linux/crypto/algapi.c (revision a8b70ccf10e38775785d9cb12ead916474549f99)
1 /*
2  * Cryptographic API for algorithms (i.e., low-level API).
3  *
4  * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the Free
8  * Software Foundation; either version 2 of the License, or (at your option)
9  * any later version.
10  *
11  */
12 
13 #include <linux/err.h>
14 #include <linux/errno.h>
15 #include <linux/fips.h>
16 #include <linux/init.h>
17 #include <linux/kernel.h>
18 #include <linux/list.h>
19 #include <linux/module.h>
20 #include <linux/rtnetlink.h>
21 #include <linux/slab.h>
22 #include <linux/string.h>
23 
24 #include "internal.h"
25 
26 static LIST_HEAD(crypto_template_list);
27 
28 static inline int crypto_set_driver_name(struct crypto_alg *alg)
29 {
30 	static const char suffix[] = "-generic";
31 	char *driver_name = alg->cra_driver_name;
32 	int len;
33 
34 	if (*driver_name)
35 		return 0;
36 
37 	len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
38 	if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME)
39 		return -ENAMETOOLONG;
40 
41 	memcpy(driver_name + len, suffix, sizeof(suffix));
42 	return 0;
43 }
44 
45 static inline void crypto_check_module_sig(struct module *mod)
46 {
47 	if (fips_enabled && mod && !module_sig_ok(mod))
48 		panic("Module %s signature verification failed in FIPS mode\n",
49 		      module_name(mod));
50 }
51 
52 static int crypto_check_alg(struct crypto_alg *alg)
53 {
54 	crypto_check_module_sig(alg->cra_module);
55 
56 	if (alg->cra_alignmask & (alg->cra_alignmask + 1))
57 		return -EINVAL;
58 
59 	if (alg->cra_blocksize > PAGE_SIZE / 8)
60 		return -EINVAL;
61 
62 	if (alg->cra_priority < 0)
63 		return -EINVAL;
64 
65 	refcount_set(&alg->cra_refcnt, 1);
66 
67 	return crypto_set_driver_name(alg);
68 }
69 
70 static void crypto_free_instance(struct crypto_instance *inst)
71 {
72 	if (!inst->alg.cra_type->free) {
73 		inst->tmpl->free(inst);
74 		return;
75 	}
76 
77 	inst->alg.cra_type->free(inst);
78 }
79 
80 static void crypto_destroy_instance(struct crypto_alg *alg)
81 {
82 	struct crypto_instance *inst = (void *)alg;
83 	struct crypto_template *tmpl = inst->tmpl;
84 
85 	crypto_free_instance(inst);
86 	crypto_tmpl_put(tmpl);
87 }
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_next_entry(spawn, list);
101 
102 	if (spawn->alg && &n->list != stack && !n->alg)
103 		n->alg = (n->list.next == stack) ? alg :
104 			 &list_next_entry(n, list)->inst->alg;
105 
106 	list_move(&spawn->list, secondary_spawns);
107 
108 	return &n->list == stack ? top : &n->inst->alg.cra_users;
109 }
110 
111 static void crypto_remove_instance(struct crypto_instance *inst,
112 				   struct list_head *list)
113 {
114 	struct crypto_template *tmpl = inst->tmpl;
115 
116 	if (crypto_is_dead(&inst->alg))
117 		return;
118 
119 	inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
120 	if (hlist_unhashed(&inst->list))
121 		return;
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 void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
134 			  struct crypto_alg *nalg)
135 {
136 	u32 new_type = (nalg ?: alg)->cra_flags;
137 	struct crypto_spawn *spawn, *n;
138 	LIST_HEAD(secondary_spawns);
139 	struct list_head *spawns;
140 	LIST_HEAD(stack);
141 	LIST_HEAD(top);
142 
143 	spawns = &alg->cra_users;
144 	list_for_each_entry_safe(spawn, n, spawns, list) {
145 		if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
146 			continue;
147 
148 		list_move(&spawn->list, &top);
149 	}
150 
151 	spawns = &top;
152 	do {
153 		while (!list_empty(spawns)) {
154 			struct crypto_instance *inst;
155 
156 			spawn = list_first_entry(spawns, struct crypto_spawn,
157 						 list);
158 			inst = spawn->inst;
159 
160 			BUG_ON(&inst->alg == alg);
161 
162 			list_move(&spawn->list, &stack);
163 
164 			if (&inst->alg == nalg)
165 				break;
166 
167 			spawn->alg = NULL;
168 			spawns = &inst->alg.cra_users;
169 
170 			/*
171 			 * We may encounter an unregistered instance here, since
172 			 * an instance's spawns are set up prior to the instance
173 			 * being registered.  An unregistered instance will have
174 			 * NULL ->cra_users.next, since ->cra_users isn't
175 			 * properly initialized until registration.  But an
176 			 * unregistered instance cannot have any users, so treat
177 			 * it the same as ->cra_users being empty.
178 			 */
179 			if (spawns->next == NULL)
180 				break;
181 		}
182 	} while ((spawns = crypto_more_spawns(alg, &stack, &top,
183 					      &secondary_spawns)));
184 
185 	list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
186 		if (spawn->alg)
187 			list_move(&spawn->list, &spawn->alg->cra_users);
188 		else
189 			crypto_remove_instance(spawn->inst, list);
190 	}
191 }
192 EXPORT_SYMBOL_GPL(crypto_remove_spawns);
193 
194 static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
195 {
196 	struct crypto_alg *q;
197 	struct crypto_larval *larval;
198 	int ret = -EAGAIN;
199 
200 	if (crypto_is_dead(alg))
201 		goto err;
202 
203 	INIT_LIST_HEAD(&alg->cra_users);
204 
205 	/* No cheating! */
206 	alg->cra_flags &= ~CRYPTO_ALG_TESTED;
207 
208 	ret = -EEXIST;
209 
210 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
211 		if (q == alg)
212 			goto err;
213 
214 		if (crypto_is_moribund(q))
215 			continue;
216 
217 		if (crypto_is_larval(q)) {
218 			if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
219 				goto err;
220 			continue;
221 		}
222 
223 		if (!strcmp(q->cra_driver_name, alg->cra_name) ||
224 		    !strcmp(q->cra_name, alg->cra_driver_name))
225 			goto err;
226 	}
227 
228 	larval = crypto_larval_alloc(alg->cra_name,
229 				     alg->cra_flags | CRYPTO_ALG_TESTED, 0);
230 	if (IS_ERR(larval))
231 		goto out;
232 
233 	ret = -ENOENT;
234 	larval->adult = crypto_mod_get(alg);
235 	if (!larval->adult)
236 		goto free_larval;
237 
238 	refcount_set(&larval->alg.cra_refcnt, 1);
239 	memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
240 	       CRYPTO_MAX_ALG_NAME);
241 	larval->alg.cra_priority = alg->cra_priority;
242 
243 	list_add(&alg->cra_list, &crypto_alg_list);
244 	list_add(&larval->alg.cra_list, &crypto_alg_list);
245 
246 out:
247 	return larval;
248 
249 free_larval:
250 	kfree(larval);
251 err:
252 	larval = ERR_PTR(ret);
253 	goto out;
254 }
255 
256 void crypto_alg_tested(const char *name, int err)
257 {
258 	struct crypto_larval *test;
259 	struct crypto_alg *alg;
260 	struct crypto_alg *q;
261 	LIST_HEAD(list);
262 
263 	down_write(&crypto_alg_sem);
264 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
265 		if (crypto_is_moribund(q) || !crypto_is_larval(q))
266 			continue;
267 
268 		test = (struct crypto_larval *)q;
269 
270 		if (!strcmp(q->cra_driver_name, name))
271 			goto found;
272 	}
273 
274 	pr_err("alg: Unexpected test result for %s: %d\n", name, err);
275 	goto unlock;
276 
277 found:
278 	q->cra_flags |= CRYPTO_ALG_DEAD;
279 	alg = test->adult;
280 	if (err || list_empty(&alg->cra_list))
281 		goto complete;
282 
283 	alg->cra_flags |= CRYPTO_ALG_TESTED;
284 
285 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
286 		if (q == alg)
287 			continue;
288 
289 		if (crypto_is_moribund(q))
290 			continue;
291 
292 		if (crypto_is_larval(q)) {
293 			struct crypto_larval *larval = (void *)q;
294 
295 			/*
296 			 * Check to see if either our generic name or
297 			 * specific name can satisfy the name requested
298 			 * by the larval entry q.
299 			 */
300 			if (strcmp(alg->cra_name, q->cra_name) &&
301 			    strcmp(alg->cra_driver_name, q->cra_name))
302 				continue;
303 
304 			if (larval->adult)
305 				continue;
306 			if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
307 				continue;
308 			if (!crypto_mod_get(alg))
309 				continue;
310 
311 			larval->adult = alg;
312 			continue;
313 		}
314 
315 		if (strcmp(alg->cra_name, q->cra_name))
316 			continue;
317 
318 		if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
319 		    q->cra_priority > alg->cra_priority)
320 			continue;
321 
322 		crypto_remove_spawns(q, &list, alg);
323 	}
324 
325 complete:
326 	complete_all(&test->completion);
327 
328 unlock:
329 	up_write(&crypto_alg_sem);
330 
331 	crypto_remove_final(&list);
332 }
333 EXPORT_SYMBOL_GPL(crypto_alg_tested);
334 
335 void crypto_remove_final(struct list_head *list)
336 {
337 	struct crypto_alg *alg;
338 	struct crypto_alg *n;
339 
340 	list_for_each_entry_safe(alg, n, list, cra_list) {
341 		list_del_init(&alg->cra_list);
342 		crypto_alg_put(alg);
343 	}
344 }
345 EXPORT_SYMBOL_GPL(crypto_remove_final);
346 
347 static void crypto_wait_for_test(struct crypto_larval *larval)
348 {
349 	int err;
350 
351 	err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
352 	if (err != NOTIFY_STOP) {
353 		if (WARN_ON(err != NOTIFY_DONE))
354 			goto out;
355 		crypto_alg_tested(larval->alg.cra_driver_name, 0);
356 	}
357 
358 	err = wait_for_completion_killable(&larval->completion);
359 	WARN_ON(err);
360 
361 out:
362 	crypto_larval_kill(&larval->alg);
363 }
364 
365 int crypto_register_alg(struct crypto_alg *alg)
366 {
367 	struct crypto_larval *larval;
368 	int err;
369 
370 	alg->cra_flags &= ~CRYPTO_ALG_DEAD;
371 	err = crypto_check_alg(alg);
372 	if (err)
373 		return err;
374 
375 	down_write(&crypto_alg_sem);
376 	larval = __crypto_register_alg(alg);
377 	up_write(&crypto_alg_sem);
378 
379 	if (IS_ERR(larval))
380 		return PTR_ERR(larval);
381 
382 	crypto_wait_for_test(larval);
383 	return 0;
384 }
385 EXPORT_SYMBOL_GPL(crypto_register_alg);
386 
387 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
388 {
389 	if (unlikely(list_empty(&alg->cra_list)))
390 		return -ENOENT;
391 
392 	alg->cra_flags |= CRYPTO_ALG_DEAD;
393 
394 	list_del_init(&alg->cra_list);
395 	crypto_remove_spawns(alg, list, NULL);
396 
397 	return 0;
398 }
399 
400 int crypto_unregister_alg(struct crypto_alg *alg)
401 {
402 	int ret;
403 	LIST_HEAD(list);
404 
405 	down_write(&crypto_alg_sem);
406 	ret = crypto_remove_alg(alg, &list);
407 	up_write(&crypto_alg_sem);
408 
409 	if (ret)
410 		return ret;
411 
412 	BUG_ON(refcount_read(&alg->cra_refcnt) != 1);
413 	if (alg->cra_destroy)
414 		alg->cra_destroy(alg);
415 
416 	crypto_remove_final(&list);
417 	return 0;
418 }
419 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
420 
421 int crypto_register_algs(struct crypto_alg *algs, int count)
422 {
423 	int i, ret;
424 
425 	for (i = 0; i < count; i++) {
426 		ret = crypto_register_alg(&algs[i]);
427 		if (ret)
428 			goto err;
429 	}
430 
431 	return 0;
432 
433 err:
434 	for (--i; i >= 0; --i)
435 		crypto_unregister_alg(&algs[i]);
436 
437 	return ret;
438 }
439 EXPORT_SYMBOL_GPL(crypto_register_algs);
440 
441 int crypto_unregister_algs(struct crypto_alg *algs, int count)
442 {
443 	int i, ret;
444 
445 	for (i = 0; i < count; i++) {
446 		ret = crypto_unregister_alg(&algs[i]);
447 		if (ret)
448 			pr_err("Failed to unregister %s %s: %d\n",
449 			       algs[i].cra_driver_name, algs[i].cra_name, ret);
450 	}
451 
452 	return 0;
453 }
454 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
455 
456 int crypto_register_template(struct crypto_template *tmpl)
457 {
458 	struct crypto_template *q;
459 	int err = -EEXIST;
460 
461 	down_write(&crypto_alg_sem);
462 
463 	crypto_check_module_sig(tmpl->module);
464 
465 	list_for_each_entry(q, &crypto_template_list, list) {
466 		if (q == tmpl)
467 			goto out;
468 	}
469 
470 	list_add(&tmpl->list, &crypto_template_list);
471 	err = 0;
472 out:
473 	up_write(&crypto_alg_sem);
474 	return err;
475 }
476 EXPORT_SYMBOL_GPL(crypto_register_template);
477 
478 void crypto_unregister_template(struct crypto_template *tmpl)
479 {
480 	struct crypto_instance *inst;
481 	struct hlist_node *n;
482 	struct hlist_head *list;
483 	LIST_HEAD(users);
484 
485 	down_write(&crypto_alg_sem);
486 
487 	BUG_ON(list_empty(&tmpl->list));
488 	list_del_init(&tmpl->list);
489 
490 	list = &tmpl->instances;
491 	hlist_for_each_entry(inst, list, list) {
492 		int err = crypto_remove_alg(&inst->alg, &users);
493 
494 		BUG_ON(err);
495 	}
496 
497 	up_write(&crypto_alg_sem);
498 
499 	hlist_for_each_entry_safe(inst, n, list, list) {
500 		BUG_ON(refcount_read(&inst->alg.cra_refcnt) != 1);
501 		crypto_free_instance(inst);
502 	}
503 	crypto_remove_final(&users);
504 }
505 EXPORT_SYMBOL_GPL(crypto_unregister_template);
506 
507 static struct crypto_template *__crypto_lookup_template(const char *name)
508 {
509 	struct crypto_template *q, *tmpl = NULL;
510 
511 	down_read(&crypto_alg_sem);
512 	list_for_each_entry(q, &crypto_template_list, list) {
513 		if (strcmp(q->name, name))
514 			continue;
515 		if (unlikely(!crypto_tmpl_get(q)))
516 			continue;
517 
518 		tmpl = q;
519 		break;
520 	}
521 	up_read(&crypto_alg_sem);
522 
523 	return tmpl;
524 }
525 
526 struct crypto_template *crypto_lookup_template(const char *name)
527 {
528 	return try_then_request_module(__crypto_lookup_template(name),
529 				       "crypto-%s", name);
530 }
531 EXPORT_SYMBOL_GPL(crypto_lookup_template);
532 
533 int crypto_register_instance(struct crypto_template *tmpl,
534 			     struct crypto_instance *inst)
535 {
536 	struct crypto_larval *larval;
537 	int err;
538 
539 	err = crypto_check_alg(&inst->alg);
540 	if (err)
541 		return err;
542 
543 	inst->alg.cra_module = tmpl->module;
544 	inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
545 
546 	down_write(&crypto_alg_sem);
547 
548 	larval = __crypto_register_alg(&inst->alg);
549 	if (IS_ERR(larval))
550 		goto unlock;
551 
552 	hlist_add_head(&inst->list, &tmpl->instances);
553 	inst->tmpl = tmpl;
554 
555 unlock:
556 	up_write(&crypto_alg_sem);
557 
558 	err = PTR_ERR(larval);
559 	if (IS_ERR(larval))
560 		goto err;
561 
562 	crypto_wait_for_test(larval);
563 	err = 0;
564 
565 err:
566 	return err;
567 }
568 EXPORT_SYMBOL_GPL(crypto_register_instance);
569 
570 int crypto_unregister_instance(struct crypto_instance *inst)
571 {
572 	LIST_HEAD(list);
573 
574 	down_write(&crypto_alg_sem);
575 
576 	crypto_remove_spawns(&inst->alg, &list, NULL);
577 	crypto_remove_instance(inst, &list);
578 
579 	up_write(&crypto_alg_sem);
580 
581 	crypto_remove_final(&list);
582 
583 	return 0;
584 }
585 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
586 
587 int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
588 		      struct crypto_instance *inst, u32 mask)
589 {
590 	int err = -EAGAIN;
591 
592 	spawn->inst = inst;
593 	spawn->mask = mask;
594 
595 	down_write(&crypto_alg_sem);
596 	if (!crypto_is_moribund(alg)) {
597 		list_add(&spawn->list, &alg->cra_users);
598 		spawn->alg = alg;
599 		err = 0;
600 	}
601 	up_write(&crypto_alg_sem);
602 
603 	return err;
604 }
605 EXPORT_SYMBOL_GPL(crypto_init_spawn);
606 
607 int crypto_init_spawn2(struct crypto_spawn *spawn, struct crypto_alg *alg,
608 		       struct crypto_instance *inst,
609 		       const struct crypto_type *frontend)
610 {
611 	int err = -EINVAL;
612 
613 	if ((alg->cra_flags ^ frontend->type) & frontend->maskset)
614 		goto out;
615 
616 	spawn->frontend = frontend;
617 	err = crypto_init_spawn(spawn, alg, inst, frontend->maskset);
618 
619 out:
620 	return err;
621 }
622 EXPORT_SYMBOL_GPL(crypto_init_spawn2);
623 
624 int crypto_grab_spawn(struct crypto_spawn *spawn, const char *name,
625 		      u32 type, u32 mask)
626 {
627 	struct crypto_alg *alg;
628 	int err;
629 
630 	alg = crypto_find_alg(name, spawn->frontend, type, mask);
631 	if (IS_ERR(alg))
632 		return PTR_ERR(alg);
633 
634 	err = crypto_init_spawn(spawn, alg, spawn->inst, mask);
635 	crypto_mod_put(alg);
636 	return err;
637 }
638 EXPORT_SYMBOL_GPL(crypto_grab_spawn);
639 
640 void crypto_drop_spawn(struct crypto_spawn *spawn)
641 {
642 	if (!spawn->alg)
643 		return;
644 
645 	down_write(&crypto_alg_sem);
646 	list_del(&spawn->list);
647 	up_write(&crypto_alg_sem);
648 }
649 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
650 
651 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
652 {
653 	struct crypto_alg *alg;
654 	struct crypto_alg *alg2;
655 
656 	down_read(&crypto_alg_sem);
657 	alg = spawn->alg;
658 	alg2 = alg;
659 	if (alg2)
660 		alg2 = crypto_mod_get(alg2);
661 	up_read(&crypto_alg_sem);
662 
663 	if (!alg2) {
664 		if (alg)
665 			crypto_shoot_alg(alg);
666 		return ERR_PTR(-EAGAIN);
667 	}
668 
669 	return alg;
670 }
671 
672 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
673 				    u32 mask)
674 {
675 	struct crypto_alg *alg;
676 	struct crypto_tfm *tfm;
677 
678 	alg = crypto_spawn_alg(spawn);
679 	if (IS_ERR(alg))
680 		return ERR_CAST(alg);
681 
682 	tfm = ERR_PTR(-EINVAL);
683 	if (unlikely((alg->cra_flags ^ type) & mask))
684 		goto out_put_alg;
685 
686 	tfm = __crypto_alloc_tfm(alg, type, mask);
687 	if (IS_ERR(tfm))
688 		goto out_put_alg;
689 
690 	return tfm;
691 
692 out_put_alg:
693 	crypto_mod_put(alg);
694 	return tfm;
695 }
696 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
697 
698 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
699 {
700 	struct crypto_alg *alg;
701 	struct crypto_tfm *tfm;
702 
703 	alg = crypto_spawn_alg(spawn);
704 	if (IS_ERR(alg))
705 		return ERR_CAST(alg);
706 
707 	tfm = crypto_create_tfm(alg, spawn->frontend);
708 	if (IS_ERR(tfm))
709 		goto out_put_alg;
710 
711 	return tfm;
712 
713 out_put_alg:
714 	crypto_mod_put(alg);
715 	return tfm;
716 }
717 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
718 
719 int crypto_register_notifier(struct notifier_block *nb)
720 {
721 	return blocking_notifier_chain_register(&crypto_chain, nb);
722 }
723 EXPORT_SYMBOL_GPL(crypto_register_notifier);
724 
725 int crypto_unregister_notifier(struct notifier_block *nb)
726 {
727 	return blocking_notifier_chain_unregister(&crypto_chain, nb);
728 }
729 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
730 
731 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
732 {
733 	struct rtattr *rta = tb[0];
734 	struct crypto_attr_type *algt;
735 
736 	if (!rta)
737 		return ERR_PTR(-ENOENT);
738 	if (RTA_PAYLOAD(rta) < sizeof(*algt))
739 		return ERR_PTR(-EINVAL);
740 	if (rta->rta_type != CRYPTOA_TYPE)
741 		return ERR_PTR(-EINVAL);
742 
743 	algt = RTA_DATA(rta);
744 
745 	return algt;
746 }
747 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
748 
749 int crypto_check_attr_type(struct rtattr **tb, u32 type)
750 {
751 	struct crypto_attr_type *algt;
752 
753 	algt = crypto_get_attr_type(tb);
754 	if (IS_ERR(algt))
755 		return PTR_ERR(algt);
756 
757 	if ((algt->type ^ type) & algt->mask)
758 		return -EINVAL;
759 
760 	return 0;
761 }
762 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
763 
764 const char *crypto_attr_alg_name(struct rtattr *rta)
765 {
766 	struct crypto_attr_alg *alga;
767 
768 	if (!rta)
769 		return ERR_PTR(-ENOENT);
770 	if (RTA_PAYLOAD(rta) < sizeof(*alga))
771 		return ERR_PTR(-EINVAL);
772 	if (rta->rta_type != CRYPTOA_ALG)
773 		return ERR_PTR(-EINVAL);
774 
775 	alga = RTA_DATA(rta);
776 	alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
777 
778 	return alga->name;
779 }
780 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
781 
782 struct crypto_alg *crypto_attr_alg2(struct rtattr *rta,
783 				    const struct crypto_type *frontend,
784 				    u32 type, u32 mask)
785 {
786 	const char *name;
787 
788 	name = crypto_attr_alg_name(rta);
789 	if (IS_ERR(name))
790 		return ERR_CAST(name);
791 
792 	return crypto_find_alg(name, frontend, type, mask);
793 }
794 EXPORT_SYMBOL_GPL(crypto_attr_alg2);
795 
796 int crypto_attr_u32(struct rtattr *rta, u32 *num)
797 {
798 	struct crypto_attr_u32 *nu32;
799 
800 	if (!rta)
801 		return -ENOENT;
802 	if (RTA_PAYLOAD(rta) < sizeof(*nu32))
803 		return -EINVAL;
804 	if (rta->rta_type != CRYPTOA_U32)
805 		return -EINVAL;
806 
807 	nu32 = RTA_DATA(rta);
808 	*num = nu32->num;
809 
810 	return 0;
811 }
812 EXPORT_SYMBOL_GPL(crypto_attr_u32);
813 
814 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
815 			struct crypto_alg *alg)
816 {
817 	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
818 		     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
819 		return -ENAMETOOLONG;
820 
821 	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
822 		     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
823 		return -ENAMETOOLONG;
824 
825 	return 0;
826 }
827 EXPORT_SYMBOL_GPL(crypto_inst_setname);
828 
829 void *crypto_alloc_instance2(const char *name, struct crypto_alg *alg,
830 			     unsigned int head)
831 {
832 	struct crypto_instance *inst;
833 	char *p;
834 	int err;
835 
836 	p = kzalloc(head + sizeof(*inst) + sizeof(struct crypto_spawn),
837 		    GFP_KERNEL);
838 	if (!p)
839 		return ERR_PTR(-ENOMEM);
840 
841 	inst = (void *)(p + head);
842 
843 	err = crypto_inst_setname(inst, name, alg);
844 	if (err)
845 		goto err_free_inst;
846 
847 	return p;
848 
849 err_free_inst:
850 	kfree(p);
851 	return ERR_PTR(err);
852 }
853 EXPORT_SYMBOL_GPL(crypto_alloc_instance2);
854 
855 struct crypto_instance *crypto_alloc_instance(const char *name,
856 					      struct crypto_alg *alg)
857 {
858 	struct crypto_instance *inst;
859 	struct crypto_spawn *spawn;
860 	int err;
861 
862 	inst = crypto_alloc_instance2(name, alg, 0);
863 	if (IS_ERR(inst))
864 		goto out;
865 
866 	spawn = crypto_instance_ctx(inst);
867 	err = crypto_init_spawn(spawn, alg, inst,
868 				CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
869 
870 	if (err)
871 		goto err_free_inst;
872 
873 	return inst;
874 
875 err_free_inst:
876 	kfree(inst);
877 	inst = ERR_PTR(err);
878 
879 out:
880 	return inst;
881 }
882 EXPORT_SYMBOL_GPL(crypto_alloc_instance);
883 
884 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
885 {
886 	INIT_LIST_HEAD(&queue->list);
887 	queue->backlog = &queue->list;
888 	queue->qlen = 0;
889 	queue->max_qlen = max_qlen;
890 }
891 EXPORT_SYMBOL_GPL(crypto_init_queue);
892 
893 int crypto_enqueue_request(struct crypto_queue *queue,
894 			   struct crypto_async_request *request)
895 {
896 	int err = -EINPROGRESS;
897 
898 	if (unlikely(queue->qlen >= queue->max_qlen)) {
899 		if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
900 			err = -ENOSPC;
901 			goto out;
902 		}
903 		err = -EBUSY;
904 		if (queue->backlog == &queue->list)
905 			queue->backlog = &request->list;
906 	}
907 
908 	queue->qlen++;
909 	list_add_tail(&request->list, &queue->list);
910 
911 out:
912 	return err;
913 }
914 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
915 
916 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
917 {
918 	struct list_head *request;
919 
920 	if (unlikely(!queue->qlen))
921 		return NULL;
922 
923 	queue->qlen--;
924 
925 	if (queue->backlog != &queue->list)
926 		queue->backlog = queue->backlog->next;
927 
928 	request = queue->list.next;
929 	list_del(request);
930 
931 	return list_entry(request, struct crypto_async_request, list);
932 }
933 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
934 
935 int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
936 {
937 	struct crypto_async_request *req;
938 
939 	list_for_each_entry(req, &queue->list, list) {
940 		if (req->tfm == tfm)
941 			return 1;
942 	}
943 
944 	return 0;
945 }
946 EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
947 
948 static inline void crypto_inc_byte(u8 *a, unsigned int size)
949 {
950 	u8 *b = (a + size);
951 	u8 c;
952 
953 	for (; size; size--) {
954 		c = *--b + 1;
955 		*b = c;
956 		if (c)
957 			break;
958 	}
959 }
960 
961 void crypto_inc(u8 *a, unsigned int size)
962 {
963 	__be32 *b = (__be32 *)(a + size);
964 	u32 c;
965 
966 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
967 	    IS_ALIGNED((unsigned long)b, __alignof__(*b)))
968 		for (; size >= 4; size -= 4) {
969 			c = be32_to_cpu(*--b) + 1;
970 			*b = cpu_to_be32(c);
971 			if (likely(c))
972 				return;
973 		}
974 
975 	crypto_inc_byte(a, size);
976 }
977 EXPORT_SYMBOL_GPL(crypto_inc);
978 
979 void __crypto_xor(u8 *dst, const u8 *src1, const u8 *src2, unsigned int len)
980 {
981 	int relalign = 0;
982 
983 	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) {
984 		int size = sizeof(unsigned long);
985 		int d = (((unsigned long)dst ^ (unsigned long)src1) |
986 			 ((unsigned long)dst ^ (unsigned long)src2)) &
987 			(size - 1);
988 
989 		relalign = d ? 1 << __ffs(d) : size;
990 
991 		/*
992 		 * If we care about alignment, process as many bytes as
993 		 * needed to advance dst and src to values whose alignments
994 		 * equal their relative alignment. This will allow us to
995 		 * process the remainder of the input using optimal strides.
996 		 */
997 		while (((unsigned long)dst & (relalign - 1)) && len > 0) {
998 			*dst++ = *src1++ ^ *src2++;
999 			len--;
1000 		}
1001 	}
1002 
1003 	while (IS_ENABLED(CONFIG_64BIT) && len >= 8 && !(relalign & 7)) {
1004 		*(u64 *)dst = *(u64 *)src1 ^  *(u64 *)src2;
1005 		dst += 8;
1006 		src1 += 8;
1007 		src2 += 8;
1008 		len -= 8;
1009 	}
1010 
1011 	while (len >= 4 && !(relalign & 3)) {
1012 		*(u32 *)dst = *(u32 *)src1 ^ *(u32 *)src2;
1013 		dst += 4;
1014 		src1 += 4;
1015 		src2 += 4;
1016 		len -= 4;
1017 	}
1018 
1019 	while (len >= 2 && !(relalign & 1)) {
1020 		*(u16 *)dst = *(u16 *)src1 ^ *(u16 *)src2;
1021 		dst += 2;
1022 		src1 += 2;
1023 		src2 += 2;
1024 		len -= 2;
1025 	}
1026 
1027 	while (len--)
1028 		*dst++ = *src1++ ^ *src2++;
1029 }
1030 EXPORT_SYMBOL_GPL(__crypto_xor);
1031 
1032 unsigned int crypto_alg_extsize(struct crypto_alg *alg)
1033 {
1034 	return alg->cra_ctxsize +
1035 	       (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
1036 }
1037 EXPORT_SYMBOL_GPL(crypto_alg_extsize);
1038 
1039 int crypto_type_has_alg(const char *name, const struct crypto_type *frontend,
1040 			u32 type, u32 mask)
1041 {
1042 	int ret = 0;
1043 	struct crypto_alg *alg = crypto_find_alg(name, frontend, type, mask);
1044 
1045 	if (!IS_ERR(alg)) {
1046 		crypto_mod_put(alg);
1047 		ret = 1;
1048 	}
1049 
1050 	return ret;
1051 }
1052 EXPORT_SYMBOL_GPL(crypto_type_has_alg);
1053 
1054 static int __init crypto_algapi_init(void)
1055 {
1056 	crypto_init_proc();
1057 	return 0;
1058 }
1059 
1060 static void __exit crypto_algapi_exit(void)
1061 {
1062 	crypto_exit_proc();
1063 }
1064 
1065 module_init(crypto_algapi_init);
1066 module_exit(crypto_algapi_exit);
1067 
1068 MODULE_LICENSE("GPL");
1069 MODULE_DESCRIPTION("Cryptographic algorithms API");
1070