xref: /openbmc/linux/crypto/algapi.c (revision 95e9fd10)
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 *p, *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, p, 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, p, 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), name);
499 }
500 EXPORT_SYMBOL_GPL(crypto_lookup_template);
501 
502 int crypto_register_instance(struct crypto_template *tmpl,
503 			     struct crypto_instance *inst)
504 {
505 	struct crypto_larval *larval;
506 	int err;
507 
508 	err = crypto_check_alg(&inst->alg);
509 	if (err)
510 		goto err;
511 
512 	inst->alg.cra_module = tmpl->module;
513 	inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
514 
515 	down_write(&crypto_alg_sem);
516 
517 	larval = __crypto_register_alg(&inst->alg);
518 	if (IS_ERR(larval))
519 		goto unlock;
520 
521 	hlist_add_head(&inst->list, &tmpl->instances);
522 	inst->tmpl = tmpl;
523 
524 unlock:
525 	up_write(&crypto_alg_sem);
526 
527 	err = PTR_ERR(larval);
528 	if (IS_ERR(larval))
529 		goto err;
530 
531 	crypto_wait_for_test(larval);
532 	err = 0;
533 
534 err:
535 	return err;
536 }
537 EXPORT_SYMBOL_GPL(crypto_register_instance);
538 
539 int crypto_unregister_instance(struct crypto_alg *alg)
540 {
541 	int err;
542 	struct crypto_instance *inst = (void *)alg;
543 	struct crypto_template *tmpl = inst->tmpl;
544 	LIST_HEAD(users);
545 
546 	if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
547 		return -EINVAL;
548 
549 	BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
550 
551 	down_write(&crypto_alg_sem);
552 
553 	hlist_del_init(&inst->list);
554 	err = crypto_remove_alg(alg, &users);
555 
556 	up_write(&crypto_alg_sem);
557 
558 	if (err)
559 		return err;
560 
561 	tmpl->free(inst);
562 	crypto_remove_final(&users);
563 
564 	return 0;
565 }
566 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
567 
568 int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
569 		      struct crypto_instance *inst, u32 mask)
570 {
571 	int err = -EAGAIN;
572 
573 	spawn->inst = inst;
574 	spawn->mask = mask;
575 
576 	down_write(&crypto_alg_sem);
577 	if (!crypto_is_moribund(alg)) {
578 		list_add(&spawn->list, &alg->cra_users);
579 		spawn->alg = alg;
580 		err = 0;
581 	}
582 	up_write(&crypto_alg_sem);
583 
584 	return err;
585 }
586 EXPORT_SYMBOL_GPL(crypto_init_spawn);
587 
588 int crypto_init_spawn2(struct crypto_spawn *spawn, struct crypto_alg *alg,
589 		       struct crypto_instance *inst,
590 		       const struct crypto_type *frontend)
591 {
592 	int err = -EINVAL;
593 
594 	if ((alg->cra_flags ^ frontend->type) & frontend->maskset)
595 		goto out;
596 
597 	spawn->frontend = frontend;
598 	err = crypto_init_spawn(spawn, alg, inst, frontend->maskset);
599 
600 out:
601 	return err;
602 }
603 EXPORT_SYMBOL_GPL(crypto_init_spawn2);
604 
605 void crypto_drop_spawn(struct crypto_spawn *spawn)
606 {
607 	if (!spawn->alg)
608 		return;
609 
610 	down_write(&crypto_alg_sem);
611 	list_del(&spawn->list);
612 	up_write(&crypto_alg_sem);
613 }
614 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
615 
616 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
617 {
618 	struct crypto_alg *alg;
619 	struct crypto_alg *alg2;
620 
621 	down_read(&crypto_alg_sem);
622 	alg = spawn->alg;
623 	alg2 = alg;
624 	if (alg2)
625 		alg2 = crypto_mod_get(alg2);
626 	up_read(&crypto_alg_sem);
627 
628 	if (!alg2) {
629 		if (alg)
630 			crypto_shoot_alg(alg);
631 		return ERR_PTR(-EAGAIN);
632 	}
633 
634 	return alg;
635 }
636 
637 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
638 				    u32 mask)
639 {
640 	struct crypto_alg *alg;
641 	struct crypto_tfm *tfm;
642 
643 	alg = crypto_spawn_alg(spawn);
644 	if (IS_ERR(alg))
645 		return ERR_CAST(alg);
646 
647 	tfm = ERR_PTR(-EINVAL);
648 	if (unlikely((alg->cra_flags ^ type) & mask))
649 		goto out_put_alg;
650 
651 	tfm = __crypto_alloc_tfm(alg, type, mask);
652 	if (IS_ERR(tfm))
653 		goto out_put_alg;
654 
655 	return tfm;
656 
657 out_put_alg:
658 	crypto_mod_put(alg);
659 	return tfm;
660 }
661 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
662 
663 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
664 {
665 	struct crypto_alg *alg;
666 	struct crypto_tfm *tfm;
667 
668 	alg = crypto_spawn_alg(spawn);
669 	if (IS_ERR(alg))
670 		return ERR_CAST(alg);
671 
672 	tfm = crypto_create_tfm(alg, spawn->frontend);
673 	if (IS_ERR(tfm))
674 		goto out_put_alg;
675 
676 	return tfm;
677 
678 out_put_alg:
679 	crypto_mod_put(alg);
680 	return tfm;
681 }
682 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
683 
684 int crypto_register_notifier(struct notifier_block *nb)
685 {
686 	return blocking_notifier_chain_register(&crypto_chain, nb);
687 }
688 EXPORT_SYMBOL_GPL(crypto_register_notifier);
689 
690 int crypto_unregister_notifier(struct notifier_block *nb)
691 {
692 	return blocking_notifier_chain_unregister(&crypto_chain, nb);
693 }
694 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
695 
696 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
697 {
698 	struct rtattr *rta = tb[0];
699 	struct crypto_attr_type *algt;
700 
701 	if (!rta)
702 		return ERR_PTR(-ENOENT);
703 	if (RTA_PAYLOAD(rta) < sizeof(*algt))
704 		return ERR_PTR(-EINVAL);
705 	if (rta->rta_type != CRYPTOA_TYPE)
706 		return ERR_PTR(-EINVAL);
707 
708 	algt = RTA_DATA(rta);
709 
710 	return algt;
711 }
712 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
713 
714 int crypto_check_attr_type(struct rtattr **tb, u32 type)
715 {
716 	struct crypto_attr_type *algt;
717 
718 	algt = crypto_get_attr_type(tb);
719 	if (IS_ERR(algt))
720 		return PTR_ERR(algt);
721 
722 	if ((algt->type ^ type) & algt->mask)
723 		return -EINVAL;
724 
725 	return 0;
726 }
727 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
728 
729 const char *crypto_attr_alg_name(struct rtattr *rta)
730 {
731 	struct crypto_attr_alg *alga;
732 
733 	if (!rta)
734 		return ERR_PTR(-ENOENT);
735 	if (RTA_PAYLOAD(rta) < sizeof(*alga))
736 		return ERR_PTR(-EINVAL);
737 	if (rta->rta_type != CRYPTOA_ALG)
738 		return ERR_PTR(-EINVAL);
739 
740 	alga = RTA_DATA(rta);
741 	alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
742 
743 	return alga->name;
744 }
745 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
746 
747 struct crypto_alg *crypto_attr_alg2(struct rtattr *rta,
748 				    const struct crypto_type *frontend,
749 				    u32 type, u32 mask)
750 {
751 	const char *name;
752 	int err;
753 
754 	name = crypto_attr_alg_name(rta);
755 	err = PTR_ERR(name);
756 	if (IS_ERR(name))
757 		return ERR_PTR(err);
758 
759 	return crypto_find_alg(name, frontend, type, mask);
760 }
761 EXPORT_SYMBOL_GPL(crypto_attr_alg2);
762 
763 int crypto_attr_u32(struct rtattr *rta, u32 *num)
764 {
765 	struct crypto_attr_u32 *nu32;
766 
767 	if (!rta)
768 		return -ENOENT;
769 	if (RTA_PAYLOAD(rta) < sizeof(*nu32))
770 		return -EINVAL;
771 	if (rta->rta_type != CRYPTOA_U32)
772 		return -EINVAL;
773 
774 	nu32 = RTA_DATA(rta);
775 	*num = nu32->num;
776 
777 	return 0;
778 }
779 EXPORT_SYMBOL_GPL(crypto_attr_u32);
780 
781 void *crypto_alloc_instance2(const char *name, struct crypto_alg *alg,
782 			     unsigned int head)
783 {
784 	struct crypto_instance *inst;
785 	char *p;
786 	int err;
787 
788 	p = kzalloc(head + sizeof(*inst) + sizeof(struct crypto_spawn),
789 		    GFP_KERNEL);
790 	if (!p)
791 		return ERR_PTR(-ENOMEM);
792 
793 	inst = (void *)(p + head);
794 
795 	err = -ENAMETOOLONG;
796 	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
797 		     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
798 		goto err_free_inst;
799 
800 	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
801 		     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
802 		goto err_free_inst;
803 
804 	return p;
805 
806 err_free_inst:
807 	kfree(p);
808 	return ERR_PTR(err);
809 }
810 EXPORT_SYMBOL_GPL(crypto_alloc_instance2);
811 
812 struct crypto_instance *crypto_alloc_instance(const char *name,
813 					      struct crypto_alg *alg)
814 {
815 	struct crypto_instance *inst;
816 	struct crypto_spawn *spawn;
817 	int err;
818 
819 	inst = crypto_alloc_instance2(name, alg, 0);
820 	if (IS_ERR(inst))
821 		goto out;
822 
823 	spawn = crypto_instance_ctx(inst);
824 	err = crypto_init_spawn(spawn, alg, inst,
825 				CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
826 
827 	if (err)
828 		goto err_free_inst;
829 
830 	return inst;
831 
832 err_free_inst:
833 	kfree(inst);
834 	inst = ERR_PTR(err);
835 
836 out:
837 	return inst;
838 }
839 EXPORT_SYMBOL_GPL(crypto_alloc_instance);
840 
841 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
842 {
843 	INIT_LIST_HEAD(&queue->list);
844 	queue->backlog = &queue->list;
845 	queue->qlen = 0;
846 	queue->max_qlen = max_qlen;
847 }
848 EXPORT_SYMBOL_GPL(crypto_init_queue);
849 
850 int crypto_enqueue_request(struct crypto_queue *queue,
851 			   struct crypto_async_request *request)
852 {
853 	int err = -EINPROGRESS;
854 
855 	if (unlikely(queue->qlen >= queue->max_qlen)) {
856 		err = -EBUSY;
857 		if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))
858 			goto out;
859 		if (queue->backlog == &queue->list)
860 			queue->backlog = &request->list;
861 	}
862 
863 	queue->qlen++;
864 	list_add_tail(&request->list, &queue->list);
865 
866 out:
867 	return err;
868 }
869 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
870 
871 void *__crypto_dequeue_request(struct crypto_queue *queue, unsigned int offset)
872 {
873 	struct list_head *request;
874 
875 	if (unlikely(!queue->qlen))
876 		return NULL;
877 
878 	queue->qlen--;
879 
880 	if (queue->backlog != &queue->list)
881 		queue->backlog = queue->backlog->next;
882 
883 	request = queue->list.next;
884 	list_del(request);
885 
886 	return (char *)list_entry(request, struct crypto_async_request, list) -
887 	       offset;
888 }
889 EXPORT_SYMBOL_GPL(__crypto_dequeue_request);
890 
891 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
892 {
893 	return __crypto_dequeue_request(queue, 0);
894 }
895 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
896 
897 int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
898 {
899 	struct crypto_async_request *req;
900 
901 	list_for_each_entry(req, &queue->list, list) {
902 		if (req->tfm == tfm)
903 			return 1;
904 	}
905 
906 	return 0;
907 }
908 EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
909 
910 static inline void crypto_inc_byte(u8 *a, unsigned int size)
911 {
912 	u8 *b = (a + size);
913 	u8 c;
914 
915 	for (; size; size--) {
916 		c = *--b + 1;
917 		*b = c;
918 		if (c)
919 			break;
920 	}
921 }
922 
923 void crypto_inc(u8 *a, unsigned int size)
924 {
925 	__be32 *b = (__be32 *)(a + size);
926 	u32 c;
927 
928 	for (; size >= 4; size -= 4) {
929 		c = be32_to_cpu(*--b) + 1;
930 		*b = cpu_to_be32(c);
931 		if (c)
932 			return;
933 	}
934 
935 	crypto_inc_byte(a, size);
936 }
937 EXPORT_SYMBOL_GPL(crypto_inc);
938 
939 static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size)
940 {
941 	for (; size; size--)
942 		*a++ ^= *b++;
943 }
944 
945 void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
946 {
947 	u32 *a = (u32 *)dst;
948 	u32 *b = (u32 *)src;
949 
950 	for (; size >= 4; size -= 4)
951 		*a++ ^= *b++;
952 
953 	crypto_xor_byte((u8 *)a, (u8 *)b, size);
954 }
955 EXPORT_SYMBOL_GPL(crypto_xor);
956 
957 static int __init crypto_algapi_init(void)
958 {
959 	crypto_init_proc();
960 	return 0;
961 }
962 
963 static void __exit crypto_algapi_exit(void)
964 {
965 	crypto_exit_proc();
966 }
967 
968 module_init(crypto_algapi_init);
969 module_exit(crypto_algapi_exit);
970 
971 MODULE_LICENSE("GPL");
972 MODULE_DESCRIPTION("Cryptographic algorithms API");
973