xref: /openbmc/linux/crypto/algapi.c (revision 8e9356c6)
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/init.h>
16 #include <linux/kernel.h>
17 #include <linux/list.h>
18 #include <linux/module.h>
19 #include <linux/rtnetlink.h>
20 #include <linux/slab.h>
21 #include <linux/string.h>
22 
23 #include "internal.h"
24 
25 static LIST_HEAD(crypto_template_list);
26 
27 static inline int crypto_set_driver_name(struct crypto_alg *alg)
28 {
29 	static const char suffix[] = "-generic";
30 	char *driver_name = alg->cra_driver_name;
31 	int len;
32 
33 	if (*driver_name)
34 		return 0;
35 
36 	len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
37 	if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME)
38 		return -ENAMETOOLONG;
39 
40 	memcpy(driver_name + len, suffix, sizeof(suffix));
41 	return 0;
42 }
43 
44 static int crypto_check_alg(struct crypto_alg *alg)
45 {
46 	if (alg->cra_alignmask & (alg->cra_alignmask + 1))
47 		return -EINVAL;
48 
49 	if (alg->cra_blocksize > PAGE_SIZE / 8)
50 		return -EINVAL;
51 
52 	if (alg->cra_priority < 0)
53 		return -EINVAL;
54 
55 	return crypto_set_driver_name(alg);
56 }
57 
58 static void crypto_destroy_instance(struct crypto_alg *alg)
59 {
60 	struct crypto_instance *inst = (void *)alg;
61 	struct crypto_template *tmpl = inst->tmpl;
62 
63 	tmpl->free(inst);
64 	crypto_tmpl_put(tmpl);
65 }
66 
67 static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
68 					    struct list_head *stack,
69 					    struct list_head *top,
70 					    struct list_head *secondary_spawns)
71 {
72 	struct crypto_spawn *spawn, *n;
73 
74 	if (list_empty(stack))
75 		return NULL;
76 
77 	spawn = list_first_entry(stack, struct crypto_spawn, list);
78 	n = list_entry(spawn->list.next, struct crypto_spawn, list);
79 
80 	if (spawn->alg && &n->list != stack && !n->alg)
81 		n->alg = (n->list.next == stack) ? alg :
82 			 &list_entry(n->list.next, struct crypto_spawn,
83 				     list)->inst->alg;
84 
85 	list_move(&spawn->list, secondary_spawns);
86 
87 	return &n->list == stack ? top : &n->inst->alg.cra_users;
88 }
89 
90 static void crypto_remove_spawn(struct crypto_spawn *spawn,
91 				struct list_head *list)
92 {
93 	struct crypto_instance *inst = spawn->inst;
94 	struct crypto_template *tmpl = inst->tmpl;
95 
96 	if (crypto_is_dead(&inst->alg))
97 		return;
98 
99 	inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
100 	if (hlist_unhashed(&inst->list))
101 		return;
102 
103 	if (!tmpl || !crypto_tmpl_get(tmpl))
104 		return;
105 
106 	crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, &inst->alg);
107 	list_move(&inst->alg.cra_list, list);
108 	hlist_del(&inst->list);
109 	inst->alg.cra_destroy = crypto_destroy_instance;
110 
111 	BUG_ON(!list_empty(&inst->alg.cra_users));
112 }
113 
114 void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
115 			  struct crypto_alg *nalg)
116 {
117 	u32 new_type = (nalg ?: alg)->cra_flags;
118 	struct crypto_spawn *spawn, *n;
119 	LIST_HEAD(secondary_spawns);
120 	struct list_head *spawns;
121 	LIST_HEAD(stack);
122 	LIST_HEAD(top);
123 
124 	spawns = &alg->cra_users;
125 	list_for_each_entry_safe(spawn, n, spawns, list) {
126 		if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
127 			continue;
128 
129 		list_move(&spawn->list, &top);
130 	}
131 
132 	spawns = &top;
133 	do {
134 		while (!list_empty(spawns)) {
135 			struct crypto_instance *inst;
136 
137 			spawn = list_first_entry(spawns, struct crypto_spawn,
138 						 list);
139 			inst = spawn->inst;
140 
141 			BUG_ON(&inst->alg == alg);
142 
143 			list_move(&spawn->list, &stack);
144 
145 			if (&inst->alg == nalg)
146 				break;
147 
148 			spawn->alg = NULL;
149 			spawns = &inst->alg.cra_users;
150 		}
151 	} while ((spawns = crypto_more_spawns(alg, &stack, &top,
152 					      &secondary_spawns)));
153 
154 	list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
155 		if (spawn->alg)
156 			list_move(&spawn->list, &spawn->alg->cra_users);
157 		else
158 			crypto_remove_spawn(spawn, list);
159 	}
160 }
161 EXPORT_SYMBOL_GPL(crypto_remove_spawns);
162 
163 static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
164 {
165 	struct crypto_alg *q;
166 	struct crypto_larval *larval;
167 	int ret = -EAGAIN;
168 
169 	if (crypto_is_dead(alg))
170 		goto err;
171 
172 	INIT_LIST_HEAD(&alg->cra_users);
173 
174 	/* No cheating! */
175 	alg->cra_flags &= ~CRYPTO_ALG_TESTED;
176 
177 	ret = -EEXIST;
178 
179 	atomic_set(&alg->cra_refcnt, 1);
180 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
181 		if (q == alg)
182 			goto err;
183 
184 		if (crypto_is_moribund(q))
185 			continue;
186 
187 		if (crypto_is_larval(q)) {
188 			if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
189 				goto err;
190 			continue;
191 		}
192 
193 		if (!strcmp(q->cra_driver_name, alg->cra_name) ||
194 		    !strcmp(q->cra_name, alg->cra_driver_name))
195 			goto err;
196 	}
197 
198 	larval = crypto_larval_alloc(alg->cra_name,
199 				     alg->cra_flags | CRYPTO_ALG_TESTED, 0);
200 	if (IS_ERR(larval))
201 		goto out;
202 
203 	ret = -ENOENT;
204 	larval->adult = crypto_mod_get(alg);
205 	if (!larval->adult)
206 		goto free_larval;
207 
208 	atomic_set(&larval->alg.cra_refcnt, 1);
209 	memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
210 	       CRYPTO_MAX_ALG_NAME);
211 	larval->alg.cra_priority = alg->cra_priority;
212 
213 	list_add(&alg->cra_list, &crypto_alg_list);
214 	list_add(&larval->alg.cra_list, &crypto_alg_list);
215 
216 out:
217 	return larval;
218 
219 free_larval:
220 	kfree(larval);
221 err:
222 	larval = ERR_PTR(ret);
223 	goto out;
224 }
225 
226 void crypto_alg_tested(const char *name, int err)
227 {
228 	struct crypto_larval *test;
229 	struct crypto_alg *alg;
230 	struct crypto_alg *q;
231 	LIST_HEAD(list);
232 
233 	down_write(&crypto_alg_sem);
234 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
235 		if (crypto_is_moribund(q) || !crypto_is_larval(q))
236 			continue;
237 
238 		test = (struct crypto_larval *)q;
239 
240 		if (!strcmp(q->cra_driver_name, name))
241 			goto found;
242 	}
243 
244 	printk(KERN_ERR "alg: Unexpected test result for %s: %d\n", name, err);
245 	goto unlock;
246 
247 found:
248 	q->cra_flags |= CRYPTO_ALG_DEAD;
249 	alg = test->adult;
250 	if (err || list_empty(&alg->cra_list))
251 		goto complete;
252 
253 	alg->cra_flags |= CRYPTO_ALG_TESTED;
254 
255 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
256 		if (q == alg)
257 			continue;
258 
259 		if (crypto_is_moribund(q))
260 			continue;
261 
262 		if (crypto_is_larval(q)) {
263 			struct crypto_larval *larval = (void *)q;
264 
265 			/*
266 			 * Check to see if either our generic name or
267 			 * specific name can satisfy the name requested
268 			 * by the larval entry q.
269 			 */
270 			if (strcmp(alg->cra_name, q->cra_name) &&
271 			    strcmp(alg->cra_driver_name, q->cra_name))
272 				continue;
273 
274 			if (larval->adult)
275 				continue;
276 			if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
277 				continue;
278 			if (!crypto_mod_get(alg))
279 				continue;
280 
281 			larval->adult = alg;
282 			continue;
283 		}
284 
285 		if (strcmp(alg->cra_name, q->cra_name))
286 			continue;
287 
288 		if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
289 		    q->cra_priority > alg->cra_priority)
290 			continue;
291 
292 		crypto_remove_spawns(q, &list, alg);
293 	}
294 
295 complete:
296 	complete_all(&test->completion);
297 
298 unlock:
299 	up_write(&crypto_alg_sem);
300 
301 	crypto_remove_final(&list);
302 }
303 EXPORT_SYMBOL_GPL(crypto_alg_tested);
304 
305 void crypto_remove_final(struct list_head *list)
306 {
307 	struct crypto_alg *alg;
308 	struct crypto_alg *n;
309 
310 	list_for_each_entry_safe(alg, n, list, cra_list) {
311 		list_del_init(&alg->cra_list);
312 		crypto_alg_put(alg);
313 	}
314 }
315 EXPORT_SYMBOL_GPL(crypto_remove_final);
316 
317 static void crypto_wait_for_test(struct crypto_larval *larval)
318 {
319 	int err;
320 
321 	err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
322 	if (err != NOTIFY_STOP) {
323 		if (WARN_ON(err != NOTIFY_DONE))
324 			goto out;
325 		crypto_alg_tested(larval->alg.cra_driver_name, 0);
326 	}
327 
328 	err = wait_for_completion_interruptible(&larval->completion);
329 	WARN_ON(err);
330 
331 out:
332 	crypto_larval_kill(&larval->alg);
333 }
334 
335 int crypto_register_alg(struct crypto_alg *alg)
336 {
337 	struct crypto_larval *larval;
338 	int err;
339 
340 	err = crypto_check_alg(alg);
341 	if (err)
342 		return err;
343 
344 	down_write(&crypto_alg_sem);
345 	larval = __crypto_register_alg(alg);
346 	up_write(&crypto_alg_sem);
347 
348 	if (IS_ERR(larval))
349 		return PTR_ERR(larval);
350 
351 	crypto_wait_for_test(larval);
352 	return 0;
353 }
354 EXPORT_SYMBOL_GPL(crypto_register_alg);
355 
356 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
357 {
358 	if (unlikely(list_empty(&alg->cra_list)))
359 		return -ENOENT;
360 
361 	alg->cra_flags |= CRYPTO_ALG_DEAD;
362 
363 	crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
364 	list_del_init(&alg->cra_list);
365 	crypto_remove_spawns(alg, list, NULL);
366 
367 	return 0;
368 }
369 
370 int crypto_unregister_alg(struct crypto_alg *alg)
371 {
372 	int ret;
373 	LIST_HEAD(list);
374 
375 	down_write(&crypto_alg_sem);
376 	ret = crypto_remove_alg(alg, &list);
377 	up_write(&crypto_alg_sem);
378 
379 	if (ret)
380 		return ret;
381 
382 	BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
383 	if (alg->cra_destroy)
384 		alg->cra_destroy(alg);
385 
386 	crypto_remove_final(&list);
387 	return 0;
388 }
389 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
390 
391 int crypto_register_algs(struct crypto_alg *algs, int count)
392 {
393 	int i, ret;
394 
395 	for (i = 0; i < count; i++) {
396 		ret = crypto_register_alg(&algs[i]);
397 		if (ret)
398 			goto err;
399 	}
400 
401 	return 0;
402 
403 err:
404 	for (--i; i >= 0; --i)
405 		crypto_unregister_alg(&algs[i]);
406 
407 	return ret;
408 }
409 EXPORT_SYMBOL_GPL(crypto_register_algs);
410 
411 int crypto_unregister_algs(struct crypto_alg *algs, int count)
412 {
413 	int i, ret;
414 
415 	for (i = 0; i < count; i++) {
416 		ret = crypto_unregister_alg(&algs[i]);
417 		if (ret)
418 			pr_err("Failed to unregister %s %s: %d\n",
419 			       algs[i].cra_driver_name, algs[i].cra_name, ret);
420 	}
421 
422 	return 0;
423 }
424 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
425 
426 int crypto_register_template(struct crypto_template *tmpl)
427 {
428 	struct crypto_template *q;
429 	int err = -EEXIST;
430 
431 	down_write(&crypto_alg_sem);
432 
433 	list_for_each_entry(q, &crypto_template_list, list) {
434 		if (q == tmpl)
435 			goto out;
436 	}
437 
438 	list_add(&tmpl->list, &crypto_template_list);
439 	crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl);
440 	err = 0;
441 out:
442 	up_write(&crypto_alg_sem);
443 	return err;
444 }
445 EXPORT_SYMBOL_GPL(crypto_register_template);
446 
447 void crypto_unregister_template(struct crypto_template *tmpl)
448 {
449 	struct crypto_instance *inst;
450 	struct hlist_node *n;
451 	struct hlist_head *list;
452 	LIST_HEAD(users);
453 
454 	down_write(&crypto_alg_sem);
455 
456 	BUG_ON(list_empty(&tmpl->list));
457 	list_del_init(&tmpl->list);
458 
459 	list = &tmpl->instances;
460 	hlist_for_each_entry(inst, list, list) {
461 		int err = crypto_remove_alg(&inst->alg, &users);
462 		BUG_ON(err);
463 	}
464 
465 	crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl);
466 
467 	up_write(&crypto_alg_sem);
468 
469 	hlist_for_each_entry_safe(inst, n, list, list) {
470 		BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1);
471 		tmpl->free(inst);
472 	}
473 	crypto_remove_final(&users);
474 }
475 EXPORT_SYMBOL_GPL(crypto_unregister_template);
476 
477 static struct crypto_template *__crypto_lookup_template(const char *name)
478 {
479 	struct crypto_template *q, *tmpl = NULL;
480 
481 	down_read(&crypto_alg_sem);
482 	list_for_each_entry(q, &crypto_template_list, list) {
483 		if (strcmp(q->name, name))
484 			continue;
485 		if (unlikely(!crypto_tmpl_get(q)))
486 			continue;
487 
488 		tmpl = q;
489 		break;
490 	}
491 	up_read(&crypto_alg_sem);
492 
493 	return tmpl;
494 }
495 
496 struct crypto_template *crypto_lookup_template(const char *name)
497 {
498 	return try_then_request_module(__crypto_lookup_template(name), "%s",
499 				       name);
500 }
501 EXPORT_SYMBOL_GPL(crypto_lookup_template);
502 
503 int crypto_register_instance(struct crypto_template *tmpl,
504 			     struct crypto_instance *inst)
505 {
506 	struct crypto_larval *larval;
507 	int err;
508 
509 	err = crypto_check_alg(&inst->alg);
510 	if (err)
511 		goto err;
512 
513 	inst->alg.cra_module = tmpl->module;
514 	inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
515 
516 	down_write(&crypto_alg_sem);
517 
518 	larval = __crypto_register_alg(&inst->alg);
519 	if (IS_ERR(larval))
520 		goto unlock;
521 
522 	hlist_add_head(&inst->list, &tmpl->instances);
523 	inst->tmpl = tmpl;
524 
525 unlock:
526 	up_write(&crypto_alg_sem);
527 
528 	err = PTR_ERR(larval);
529 	if (IS_ERR(larval))
530 		goto err;
531 
532 	crypto_wait_for_test(larval);
533 	err = 0;
534 
535 err:
536 	return err;
537 }
538 EXPORT_SYMBOL_GPL(crypto_register_instance);
539 
540 int crypto_unregister_instance(struct crypto_alg *alg)
541 {
542 	int err;
543 	struct crypto_instance *inst = (void *)alg;
544 	struct crypto_template *tmpl = inst->tmpl;
545 	LIST_HEAD(users);
546 
547 	if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
548 		return -EINVAL;
549 
550 	BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
551 
552 	down_write(&crypto_alg_sem);
553 
554 	hlist_del_init(&inst->list);
555 	err = crypto_remove_alg(alg, &users);
556 
557 	up_write(&crypto_alg_sem);
558 
559 	if (err)
560 		return err;
561 
562 	tmpl->free(inst);
563 	crypto_remove_final(&users);
564 
565 	return 0;
566 }
567 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
568 
569 int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
570 		      struct crypto_instance *inst, u32 mask)
571 {
572 	int err = -EAGAIN;
573 
574 	spawn->inst = inst;
575 	spawn->mask = mask;
576 
577 	down_write(&crypto_alg_sem);
578 	if (!crypto_is_moribund(alg)) {
579 		list_add(&spawn->list, &alg->cra_users);
580 		spawn->alg = alg;
581 		err = 0;
582 	}
583 	up_write(&crypto_alg_sem);
584 
585 	return err;
586 }
587 EXPORT_SYMBOL_GPL(crypto_init_spawn);
588 
589 int crypto_init_spawn2(struct crypto_spawn *spawn, struct crypto_alg *alg,
590 		       struct crypto_instance *inst,
591 		       const struct crypto_type *frontend)
592 {
593 	int err = -EINVAL;
594 
595 	if ((alg->cra_flags ^ frontend->type) & frontend->maskset)
596 		goto out;
597 
598 	spawn->frontend = frontend;
599 	err = crypto_init_spawn(spawn, alg, inst, frontend->maskset);
600 
601 out:
602 	return err;
603 }
604 EXPORT_SYMBOL_GPL(crypto_init_spawn2);
605 
606 void crypto_drop_spawn(struct crypto_spawn *spawn)
607 {
608 	if (!spawn->alg)
609 		return;
610 
611 	down_write(&crypto_alg_sem);
612 	list_del(&spawn->list);
613 	up_write(&crypto_alg_sem);
614 }
615 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
616 
617 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
618 {
619 	struct crypto_alg *alg;
620 	struct crypto_alg *alg2;
621 
622 	down_read(&crypto_alg_sem);
623 	alg = spawn->alg;
624 	alg2 = alg;
625 	if (alg2)
626 		alg2 = crypto_mod_get(alg2);
627 	up_read(&crypto_alg_sem);
628 
629 	if (!alg2) {
630 		if (alg)
631 			crypto_shoot_alg(alg);
632 		return ERR_PTR(-EAGAIN);
633 	}
634 
635 	return alg;
636 }
637 
638 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
639 				    u32 mask)
640 {
641 	struct crypto_alg *alg;
642 	struct crypto_tfm *tfm;
643 
644 	alg = crypto_spawn_alg(spawn);
645 	if (IS_ERR(alg))
646 		return ERR_CAST(alg);
647 
648 	tfm = ERR_PTR(-EINVAL);
649 	if (unlikely((alg->cra_flags ^ type) & mask))
650 		goto out_put_alg;
651 
652 	tfm = __crypto_alloc_tfm(alg, type, mask);
653 	if (IS_ERR(tfm))
654 		goto out_put_alg;
655 
656 	return tfm;
657 
658 out_put_alg:
659 	crypto_mod_put(alg);
660 	return tfm;
661 }
662 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
663 
664 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
665 {
666 	struct crypto_alg *alg;
667 	struct crypto_tfm *tfm;
668 
669 	alg = crypto_spawn_alg(spawn);
670 	if (IS_ERR(alg))
671 		return ERR_CAST(alg);
672 
673 	tfm = crypto_create_tfm(alg, spawn->frontend);
674 	if (IS_ERR(tfm))
675 		goto out_put_alg;
676 
677 	return tfm;
678 
679 out_put_alg:
680 	crypto_mod_put(alg);
681 	return tfm;
682 }
683 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
684 
685 int crypto_register_notifier(struct notifier_block *nb)
686 {
687 	return blocking_notifier_chain_register(&crypto_chain, nb);
688 }
689 EXPORT_SYMBOL_GPL(crypto_register_notifier);
690 
691 int crypto_unregister_notifier(struct notifier_block *nb)
692 {
693 	return blocking_notifier_chain_unregister(&crypto_chain, nb);
694 }
695 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
696 
697 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
698 {
699 	struct rtattr *rta = tb[0];
700 	struct crypto_attr_type *algt;
701 
702 	if (!rta)
703 		return ERR_PTR(-ENOENT);
704 	if (RTA_PAYLOAD(rta) < sizeof(*algt))
705 		return ERR_PTR(-EINVAL);
706 	if (rta->rta_type != CRYPTOA_TYPE)
707 		return ERR_PTR(-EINVAL);
708 
709 	algt = RTA_DATA(rta);
710 
711 	return algt;
712 }
713 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
714 
715 int crypto_check_attr_type(struct rtattr **tb, u32 type)
716 {
717 	struct crypto_attr_type *algt;
718 
719 	algt = crypto_get_attr_type(tb);
720 	if (IS_ERR(algt))
721 		return PTR_ERR(algt);
722 
723 	if ((algt->type ^ type) & algt->mask)
724 		return -EINVAL;
725 
726 	return 0;
727 }
728 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
729 
730 const char *crypto_attr_alg_name(struct rtattr *rta)
731 {
732 	struct crypto_attr_alg *alga;
733 
734 	if (!rta)
735 		return ERR_PTR(-ENOENT);
736 	if (RTA_PAYLOAD(rta) < sizeof(*alga))
737 		return ERR_PTR(-EINVAL);
738 	if (rta->rta_type != CRYPTOA_ALG)
739 		return ERR_PTR(-EINVAL);
740 
741 	alga = RTA_DATA(rta);
742 	alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
743 
744 	return alga->name;
745 }
746 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
747 
748 struct crypto_alg *crypto_attr_alg2(struct rtattr *rta,
749 				    const struct crypto_type *frontend,
750 				    u32 type, u32 mask)
751 {
752 	const char *name;
753 
754 	name = crypto_attr_alg_name(rta);
755 	if (IS_ERR(name))
756 		return ERR_CAST(name);
757 
758 	return crypto_find_alg(name, frontend, type, mask);
759 }
760 EXPORT_SYMBOL_GPL(crypto_attr_alg2);
761 
762 int crypto_attr_u32(struct rtattr *rta, u32 *num)
763 {
764 	struct crypto_attr_u32 *nu32;
765 
766 	if (!rta)
767 		return -ENOENT;
768 	if (RTA_PAYLOAD(rta) < sizeof(*nu32))
769 		return -EINVAL;
770 	if (rta->rta_type != CRYPTOA_U32)
771 		return -EINVAL;
772 
773 	nu32 = RTA_DATA(rta);
774 	*num = nu32->num;
775 
776 	return 0;
777 }
778 EXPORT_SYMBOL_GPL(crypto_attr_u32);
779 
780 void *crypto_alloc_instance2(const char *name, struct crypto_alg *alg,
781 			     unsigned int head)
782 {
783 	struct crypto_instance *inst;
784 	char *p;
785 	int err;
786 
787 	p = kzalloc(head + sizeof(*inst) + sizeof(struct crypto_spawn),
788 		    GFP_KERNEL);
789 	if (!p)
790 		return ERR_PTR(-ENOMEM);
791 
792 	inst = (void *)(p + head);
793 
794 	err = -ENAMETOOLONG;
795 	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
796 		     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
797 		goto err_free_inst;
798 
799 	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
800 		     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
801 		goto err_free_inst;
802 
803 	return p;
804 
805 err_free_inst:
806 	kfree(p);
807 	return ERR_PTR(err);
808 }
809 EXPORT_SYMBOL_GPL(crypto_alloc_instance2);
810 
811 struct crypto_instance *crypto_alloc_instance(const char *name,
812 					      struct crypto_alg *alg)
813 {
814 	struct crypto_instance *inst;
815 	struct crypto_spawn *spawn;
816 	int err;
817 
818 	inst = crypto_alloc_instance2(name, alg, 0);
819 	if (IS_ERR(inst))
820 		goto out;
821 
822 	spawn = crypto_instance_ctx(inst);
823 	err = crypto_init_spawn(spawn, alg, inst,
824 				CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
825 
826 	if (err)
827 		goto err_free_inst;
828 
829 	return inst;
830 
831 err_free_inst:
832 	kfree(inst);
833 	inst = ERR_PTR(err);
834 
835 out:
836 	return inst;
837 }
838 EXPORT_SYMBOL_GPL(crypto_alloc_instance);
839 
840 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
841 {
842 	INIT_LIST_HEAD(&queue->list);
843 	queue->backlog = &queue->list;
844 	queue->qlen = 0;
845 	queue->max_qlen = max_qlen;
846 }
847 EXPORT_SYMBOL_GPL(crypto_init_queue);
848 
849 int crypto_enqueue_request(struct crypto_queue *queue,
850 			   struct crypto_async_request *request)
851 {
852 	int err = -EINPROGRESS;
853 
854 	if (unlikely(queue->qlen >= queue->max_qlen)) {
855 		err = -EBUSY;
856 		if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))
857 			goto out;
858 		if (queue->backlog == &queue->list)
859 			queue->backlog = &request->list;
860 	}
861 
862 	queue->qlen++;
863 	list_add_tail(&request->list, &queue->list);
864 
865 out:
866 	return err;
867 }
868 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
869 
870 void *__crypto_dequeue_request(struct crypto_queue *queue, unsigned int offset)
871 {
872 	struct list_head *request;
873 
874 	if (unlikely(!queue->qlen))
875 		return NULL;
876 
877 	queue->qlen--;
878 
879 	if (queue->backlog != &queue->list)
880 		queue->backlog = queue->backlog->next;
881 
882 	request = queue->list.next;
883 	list_del(request);
884 
885 	return (char *)list_entry(request, struct crypto_async_request, list) -
886 	       offset;
887 }
888 EXPORT_SYMBOL_GPL(__crypto_dequeue_request);
889 
890 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
891 {
892 	return __crypto_dequeue_request(queue, 0);
893 }
894 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
895 
896 int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
897 {
898 	struct crypto_async_request *req;
899 
900 	list_for_each_entry(req, &queue->list, list) {
901 		if (req->tfm == tfm)
902 			return 1;
903 	}
904 
905 	return 0;
906 }
907 EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
908 
909 static inline void crypto_inc_byte(u8 *a, unsigned int size)
910 {
911 	u8 *b = (a + size);
912 	u8 c;
913 
914 	for (; size; size--) {
915 		c = *--b + 1;
916 		*b = c;
917 		if (c)
918 			break;
919 	}
920 }
921 
922 void crypto_inc(u8 *a, unsigned int size)
923 {
924 	__be32 *b = (__be32 *)(a + size);
925 	u32 c;
926 
927 	for (; size >= 4; size -= 4) {
928 		c = be32_to_cpu(*--b) + 1;
929 		*b = cpu_to_be32(c);
930 		if (c)
931 			return;
932 	}
933 
934 	crypto_inc_byte(a, size);
935 }
936 EXPORT_SYMBOL_GPL(crypto_inc);
937 
938 static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size)
939 {
940 	for (; size; size--)
941 		*a++ ^= *b++;
942 }
943 
944 void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
945 {
946 	u32 *a = (u32 *)dst;
947 	u32 *b = (u32 *)src;
948 
949 	for (; size >= 4; size -= 4)
950 		*a++ ^= *b++;
951 
952 	crypto_xor_byte((u8 *)a, (u8 *)b, size);
953 }
954 EXPORT_SYMBOL_GPL(crypto_xor);
955 
956 static int __init crypto_algapi_init(void)
957 {
958 	crypto_init_proc();
959 	return 0;
960 }
961 
962 static void __exit crypto_algapi_exit(void)
963 {
964 	crypto_exit_proc();
965 }
966 
967 module_init(crypto_algapi_init);
968 module_exit(crypto_algapi_exit);
969 
970 MODULE_LICENSE("GPL");
971 MODULE_DESCRIPTION("Cryptographic algorithms API");
972