xref: /openbmc/linux/crypto/algapi.c (revision 171f1bc7)
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 void crypto_larval_error(const char *name, u32 type, u32 mask)
28 {
29 	struct crypto_alg *alg;
30 
31 	alg = crypto_alg_lookup(name, type, mask);
32 
33 	if (alg) {
34 		if (crypto_is_larval(alg)) {
35 			struct crypto_larval *larval = (void *)alg;
36 			complete_all(&larval->completion);
37 		}
38 		crypto_mod_put(alg);
39 	}
40 }
41 EXPORT_SYMBOL_GPL(crypto_larval_error);
42 
43 static inline int crypto_set_driver_name(struct crypto_alg *alg)
44 {
45 	static const char suffix[] = "-generic";
46 	char *driver_name = alg->cra_driver_name;
47 	int len;
48 
49 	if (*driver_name)
50 		return 0;
51 
52 	len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
53 	if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME)
54 		return -ENAMETOOLONG;
55 
56 	memcpy(driver_name + len, suffix, sizeof(suffix));
57 	return 0;
58 }
59 
60 static int crypto_check_alg(struct crypto_alg *alg)
61 {
62 	if (alg->cra_alignmask & (alg->cra_alignmask + 1))
63 		return -EINVAL;
64 
65 	if (alg->cra_blocksize > PAGE_SIZE / 8)
66 		return -EINVAL;
67 
68 	if (alg->cra_priority < 0)
69 		return -EINVAL;
70 
71 	return crypto_set_driver_name(alg);
72 }
73 
74 static void crypto_destroy_instance(struct crypto_alg *alg)
75 {
76 	struct crypto_instance *inst = (void *)alg;
77 	struct crypto_template *tmpl = inst->tmpl;
78 
79 	tmpl->free(inst);
80 	crypto_tmpl_put(tmpl);
81 }
82 
83 static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
84 					    struct list_head *stack,
85 					    struct list_head *top,
86 					    struct list_head *secondary_spawns)
87 {
88 	struct crypto_spawn *spawn, *n;
89 
90 	if (list_empty(stack))
91 		return NULL;
92 
93 	spawn = list_first_entry(stack, struct crypto_spawn, list);
94 	n = list_entry(spawn->list.next, struct crypto_spawn, list);
95 
96 	if (spawn->alg && &n->list != stack && !n->alg)
97 		n->alg = (n->list.next == stack) ? alg :
98 			 &list_entry(n->list.next, struct crypto_spawn,
99 				     list)->inst->alg;
100 
101 	list_move(&spawn->list, secondary_spawns);
102 
103 	return &n->list == stack ? top : &n->inst->alg.cra_users;
104 }
105 
106 static void crypto_remove_spawn(struct crypto_spawn *spawn,
107 				struct list_head *list)
108 {
109 	struct crypto_instance *inst = spawn->inst;
110 	struct crypto_template *tmpl = inst->tmpl;
111 
112 	if (crypto_is_dead(&inst->alg))
113 		return;
114 
115 	inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
116 	if (hlist_unhashed(&inst->list))
117 		return;
118 
119 	if (!tmpl || !crypto_tmpl_get(tmpl))
120 		return;
121 
122 	crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, &inst->alg);
123 	list_move(&inst->alg.cra_list, list);
124 	hlist_del(&inst->list);
125 	inst->alg.cra_destroy = crypto_destroy_instance;
126 
127 	BUG_ON(!list_empty(&inst->alg.cra_users));
128 }
129 
130 void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
131 			  struct crypto_alg *nalg)
132 {
133 	u32 new_type = (nalg ?: alg)->cra_flags;
134 	struct crypto_spawn *spawn, *n;
135 	LIST_HEAD(secondary_spawns);
136 	struct list_head *spawns;
137 	LIST_HEAD(stack);
138 	LIST_HEAD(top);
139 
140 	spawns = &alg->cra_users;
141 	list_for_each_entry_safe(spawn, n, spawns, list) {
142 		if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
143 			continue;
144 
145 		list_move(&spawn->list, &top);
146 	}
147 
148 	spawns = &top;
149 	do {
150 		while (!list_empty(spawns)) {
151 			struct crypto_instance *inst;
152 
153 			spawn = list_first_entry(spawns, struct crypto_spawn,
154 						 list);
155 			inst = spawn->inst;
156 
157 			BUG_ON(&inst->alg == alg);
158 
159 			list_move(&spawn->list, &stack);
160 
161 			if (&inst->alg == nalg)
162 				break;
163 
164 			spawn->alg = NULL;
165 			spawns = &inst->alg.cra_users;
166 		}
167 	} while ((spawns = crypto_more_spawns(alg, &stack, &top,
168 					      &secondary_spawns)));
169 
170 	list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
171 		if (spawn->alg)
172 			list_move(&spawn->list, &spawn->alg->cra_users);
173 		else
174 			crypto_remove_spawn(spawn, list);
175 	}
176 }
177 EXPORT_SYMBOL_GPL(crypto_remove_spawns);
178 
179 static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
180 {
181 	struct crypto_alg *q;
182 	struct crypto_larval *larval;
183 	int ret = -EAGAIN;
184 
185 	if (crypto_is_dead(alg))
186 		goto err;
187 
188 	INIT_LIST_HEAD(&alg->cra_users);
189 
190 	/* No cheating! */
191 	alg->cra_flags &= ~CRYPTO_ALG_TESTED;
192 
193 	ret = -EEXIST;
194 
195 	atomic_set(&alg->cra_refcnt, 1);
196 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
197 		if (q == alg)
198 			goto err;
199 
200 		if (crypto_is_moribund(q))
201 			continue;
202 
203 		if (crypto_is_larval(q)) {
204 			if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
205 				goto err;
206 			continue;
207 		}
208 
209 		if (!strcmp(q->cra_driver_name, alg->cra_name) ||
210 		    !strcmp(q->cra_name, alg->cra_driver_name))
211 			goto err;
212 	}
213 
214 	larval = crypto_larval_alloc(alg->cra_name,
215 				     alg->cra_flags | CRYPTO_ALG_TESTED, 0);
216 	if (IS_ERR(larval))
217 		goto out;
218 
219 	ret = -ENOENT;
220 	larval->adult = crypto_mod_get(alg);
221 	if (!larval->adult)
222 		goto free_larval;
223 
224 	atomic_set(&larval->alg.cra_refcnt, 1);
225 	memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
226 	       CRYPTO_MAX_ALG_NAME);
227 	larval->alg.cra_priority = alg->cra_priority;
228 
229 	list_add(&alg->cra_list, &crypto_alg_list);
230 	list_add(&larval->alg.cra_list, &crypto_alg_list);
231 
232 out:
233 	return larval;
234 
235 free_larval:
236 	kfree(larval);
237 err:
238 	larval = ERR_PTR(ret);
239 	goto out;
240 }
241 
242 void crypto_alg_tested(const char *name, int err)
243 {
244 	struct crypto_larval *test;
245 	struct crypto_alg *alg;
246 	struct crypto_alg *q;
247 	LIST_HEAD(list);
248 
249 	down_write(&crypto_alg_sem);
250 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
251 		if (crypto_is_moribund(q) || !crypto_is_larval(q))
252 			continue;
253 
254 		test = (struct crypto_larval *)q;
255 
256 		if (!strcmp(q->cra_driver_name, name))
257 			goto found;
258 	}
259 
260 	printk(KERN_ERR "alg: Unexpected test result for %s: %d\n", name, err);
261 	goto unlock;
262 
263 found:
264 	q->cra_flags |= CRYPTO_ALG_DEAD;
265 	alg = test->adult;
266 	if (err || list_empty(&alg->cra_list))
267 		goto complete;
268 
269 	alg->cra_flags |= CRYPTO_ALG_TESTED;
270 
271 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
272 		if (q == alg)
273 			continue;
274 
275 		if (crypto_is_moribund(q))
276 			continue;
277 
278 		if (crypto_is_larval(q)) {
279 			struct crypto_larval *larval = (void *)q;
280 
281 			/*
282 			 * Check to see if either our generic name or
283 			 * specific name can satisfy the name requested
284 			 * by the larval entry q.
285 			 */
286 			if (strcmp(alg->cra_name, q->cra_name) &&
287 			    strcmp(alg->cra_driver_name, q->cra_name))
288 				continue;
289 
290 			if (larval->adult)
291 				continue;
292 			if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
293 				continue;
294 			if (!crypto_mod_get(alg))
295 				continue;
296 
297 			larval->adult = alg;
298 			complete_all(&larval->completion);
299 			continue;
300 		}
301 
302 		if (strcmp(alg->cra_name, q->cra_name))
303 			continue;
304 
305 		if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
306 		    q->cra_priority > alg->cra_priority)
307 			continue;
308 
309 		crypto_remove_spawns(q, &list, alg);
310 	}
311 
312 complete:
313 	complete_all(&test->completion);
314 
315 unlock:
316 	up_write(&crypto_alg_sem);
317 
318 	crypto_remove_final(&list);
319 }
320 EXPORT_SYMBOL_GPL(crypto_alg_tested);
321 
322 void crypto_remove_final(struct list_head *list)
323 {
324 	struct crypto_alg *alg;
325 	struct crypto_alg *n;
326 
327 	list_for_each_entry_safe(alg, n, list, cra_list) {
328 		list_del_init(&alg->cra_list);
329 		crypto_alg_put(alg);
330 	}
331 }
332 EXPORT_SYMBOL_GPL(crypto_remove_final);
333 
334 static void crypto_wait_for_test(struct crypto_larval *larval)
335 {
336 	int err;
337 
338 	err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
339 	if (err != NOTIFY_STOP) {
340 		if (WARN_ON(err != NOTIFY_DONE))
341 			goto out;
342 		crypto_alg_tested(larval->alg.cra_driver_name, 0);
343 	}
344 
345 	err = wait_for_completion_interruptible(&larval->completion);
346 	WARN_ON(err);
347 
348 out:
349 	crypto_larval_kill(&larval->alg);
350 }
351 
352 int crypto_register_alg(struct crypto_alg *alg)
353 {
354 	struct crypto_larval *larval;
355 	int err;
356 
357 	err = crypto_check_alg(alg);
358 	if (err)
359 		return err;
360 
361 	down_write(&crypto_alg_sem);
362 	larval = __crypto_register_alg(alg);
363 	up_write(&crypto_alg_sem);
364 
365 	if (IS_ERR(larval))
366 		return PTR_ERR(larval);
367 
368 	crypto_wait_for_test(larval);
369 	return 0;
370 }
371 EXPORT_SYMBOL_GPL(crypto_register_alg);
372 
373 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
374 {
375 	if (unlikely(list_empty(&alg->cra_list)))
376 		return -ENOENT;
377 
378 	alg->cra_flags |= CRYPTO_ALG_DEAD;
379 
380 	crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
381 	list_del_init(&alg->cra_list);
382 	crypto_remove_spawns(alg, list, NULL);
383 
384 	return 0;
385 }
386 
387 int crypto_unregister_alg(struct crypto_alg *alg)
388 {
389 	int ret;
390 	LIST_HEAD(list);
391 
392 	down_write(&crypto_alg_sem);
393 	ret = crypto_remove_alg(alg, &list);
394 	up_write(&crypto_alg_sem);
395 
396 	if (ret)
397 		return ret;
398 
399 	BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
400 	if (alg->cra_destroy)
401 		alg->cra_destroy(alg);
402 
403 	crypto_remove_final(&list);
404 	return 0;
405 }
406 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
407 
408 int crypto_register_template(struct crypto_template *tmpl)
409 {
410 	struct crypto_template *q;
411 	int err = -EEXIST;
412 
413 	down_write(&crypto_alg_sem);
414 
415 	list_for_each_entry(q, &crypto_template_list, list) {
416 		if (q == tmpl)
417 			goto out;
418 	}
419 
420 	list_add(&tmpl->list, &crypto_template_list);
421 	crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl);
422 	err = 0;
423 out:
424 	up_write(&crypto_alg_sem);
425 	return err;
426 }
427 EXPORT_SYMBOL_GPL(crypto_register_template);
428 
429 void crypto_unregister_template(struct crypto_template *tmpl)
430 {
431 	struct crypto_instance *inst;
432 	struct hlist_node *p, *n;
433 	struct hlist_head *list;
434 	LIST_HEAD(users);
435 
436 	down_write(&crypto_alg_sem);
437 
438 	BUG_ON(list_empty(&tmpl->list));
439 	list_del_init(&tmpl->list);
440 
441 	list = &tmpl->instances;
442 	hlist_for_each_entry(inst, p, list, list) {
443 		int err = crypto_remove_alg(&inst->alg, &users);
444 		BUG_ON(err);
445 	}
446 
447 	crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl);
448 
449 	up_write(&crypto_alg_sem);
450 
451 	hlist_for_each_entry_safe(inst, p, n, list, list) {
452 		BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1);
453 		tmpl->free(inst);
454 	}
455 	crypto_remove_final(&users);
456 }
457 EXPORT_SYMBOL_GPL(crypto_unregister_template);
458 
459 static struct crypto_template *__crypto_lookup_template(const char *name)
460 {
461 	struct crypto_template *q, *tmpl = NULL;
462 
463 	down_read(&crypto_alg_sem);
464 	list_for_each_entry(q, &crypto_template_list, list) {
465 		if (strcmp(q->name, name))
466 			continue;
467 		if (unlikely(!crypto_tmpl_get(q)))
468 			continue;
469 
470 		tmpl = q;
471 		break;
472 	}
473 	up_read(&crypto_alg_sem);
474 
475 	return tmpl;
476 }
477 
478 struct crypto_template *crypto_lookup_template(const char *name)
479 {
480 	return try_then_request_module(__crypto_lookup_template(name), name);
481 }
482 EXPORT_SYMBOL_GPL(crypto_lookup_template);
483 
484 int crypto_register_instance(struct crypto_template *tmpl,
485 			     struct crypto_instance *inst)
486 {
487 	struct crypto_larval *larval;
488 	int err;
489 
490 	err = crypto_check_alg(&inst->alg);
491 	if (err)
492 		goto err;
493 
494 	inst->alg.cra_module = tmpl->module;
495 	inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
496 
497 	down_write(&crypto_alg_sem);
498 
499 	larval = __crypto_register_alg(&inst->alg);
500 	if (IS_ERR(larval))
501 		goto unlock;
502 
503 	hlist_add_head(&inst->list, &tmpl->instances);
504 	inst->tmpl = tmpl;
505 
506 unlock:
507 	up_write(&crypto_alg_sem);
508 
509 	err = PTR_ERR(larval);
510 	if (IS_ERR(larval))
511 		goto err;
512 
513 	crypto_wait_for_test(larval);
514 	err = 0;
515 
516 err:
517 	return err;
518 }
519 EXPORT_SYMBOL_GPL(crypto_register_instance);
520 
521 int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
522 		      struct crypto_instance *inst, u32 mask)
523 {
524 	int err = -EAGAIN;
525 
526 	spawn->inst = inst;
527 	spawn->mask = mask;
528 
529 	down_write(&crypto_alg_sem);
530 	if (!crypto_is_moribund(alg)) {
531 		list_add(&spawn->list, &alg->cra_users);
532 		spawn->alg = alg;
533 		err = 0;
534 	}
535 	up_write(&crypto_alg_sem);
536 
537 	return err;
538 }
539 EXPORT_SYMBOL_GPL(crypto_init_spawn);
540 
541 int crypto_init_spawn2(struct crypto_spawn *spawn, struct crypto_alg *alg,
542 		       struct crypto_instance *inst,
543 		       const struct crypto_type *frontend)
544 {
545 	int err = -EINVAL;
546 
547 	if ((alg->cra_flags ^ frontend->type) & frontend->maskset)
548 		goto out;
549 
550 	spawn->frontend = frontend;
551 	err = crypto_init_spawn(spawn, alg, inst, frontend->maskset);
552 
553 out:
554 	return err;
555 }
556 EXPORT_SYMBOL_GPL(crypto_init_spawn2);
557 
558 void crypto_drop_spawn(struct crypto_spawn *spawn)
559 {
560 	if (!spawn->alg)
561 		return;
562 
563 	down_write(&crypto_alg_sem);
564 	list_del(&spawn->list);
565 	up_write(&crypto_alg_sem);
566 }
567 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
568 
569 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
570 {
571 	struct crypto_alg *alg;
572 	struct crypto_alg *alg2;
573 
574 	down_read(&crypto_alg_sem);
575 	alg = spawn->alg;
576 	alg2 = alg;
577 	if (alg2)
578 		alg2 = crypto_mod_get(alg2);
579 	up_read(&crypto_alg_sem);
580 
581 	if (!alg2) {
582 		if (alg)
583 			crypto_shoot_alg(alg);
584 		return ERR_PTR(-EAGAIN);
585 	}
586 
587 	return alg;
588 }
589 
590 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
591 				    u32 mask)
592 {
593 	struct crypto_alg *alg;
594 	struct crypto_tfm *tfm;
595 
596 	alg = crypto_spawn_alg(spawn);
597 	if (IS_ERR(alg))
598 		return ERR_CAST(alg);
599 
600 	tfm = ERR_PTR(-EINVAL);
601 	if (unlikely((alg->cra_flags ^ type) & mask))
602 		goto out_put_alg;
603 
604 	tfm = __crypto_alloc_tfm(alg, type, mask);
605 	if (IS_ERR(tfm))
606 		goto out_put_alg;
607 
608 	return tfm;
609 
610 out_put_alg:
611 	crypto_mod_put(alg);
612 	return tfm;
613 }
614 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
615 
616 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
617 {
618 	struct crypto_alg *alg;
619 	struct crypto_tfm *tfm;
620 
621 	alg = crypto_spawn_alg(spawn);
622 	if (IS_ERR(alg))
623 		return ERR_CAST(alg);
624 
625 	tfm = crypto_create_tfm(alg, spawn->frontend);
626 	if (IS_ERR(tfm))
627 		goto out_put_alg;
628 
629 	return tfm;
630 
631 out_put_alg:
632 	crypto_mod_put(alg);
633 	return tfm;
634 }
635 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
636 
637 int crypto_register_notifier(struct notifier_block *nb)
638 {
639 	return blocking_notifier_chain_register(&crypto_chain, nb);
640 }
641 EXPORT_SYMBOL_GPL(crypto_register_notifier);
642 
643 int crypto_unregister_notifier(struct notifier_block *nb)
644 {
645 	return blocking_notifier_chain_unregister(&crypto_chain, nb);
646 }
647 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
648 
649 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
650 {
651 	struct rtattr *rta = tb[0];
652 	struct crypto_attr_type *algt;
653 
654 	if (!rta)
655 		return ERR_PTR(-ENOENT);
656 	if (RTA_PAYLOAD(rta) < sizeof(*algt))
657 		return ERR_PTR(-EINVAL);
658 	if (rta->rta_type != CRYPTOA_TYPE)
659 		return ERR_PTR(-EINVAL);
660 
661 	algt = RTA_DATA(rta);
662 
663 	return algt;
664 }
665 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
666 
667 int crypto_check_attr_type(struct rtattr **tb, u32 type)
668 {
669 	struct crypto_attr_type *algt;
670 
671 	algt = crypto_get_attr_type(tb);
672 	if (IS_ERR(algt))
673 		return PTR_ERR(algt);
674 
675 	if ((algt->type ^ type) & algt->mask)
676 		return -EINVAL;
677 
678 	return 0;
679 }
680 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
681 
682 const char *crypto_attr_alg_name(struct rtattr *rta)
683 {
684 	struct crypto_attr_alg *alga;
685 
686 	if (!rta)
687 		return ERR_PTR(-ENOENT);
688 	if (RTA_PAYLOAD(rta) < sizeof(*alga))
689 		return ERR_PTR(-EINVAL);
690 	if (rta->rta_type != CRYPTOA_ALG)
691 		return ERR_PTR(-EINVAL);
692 
693 	alga = RTA_DATA(rta);
694 	alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
695 
696 	return alga->name;
697 }
698 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
699 
700 struct crypto_alg *crypto_attr_alg2(struct rtattr *rta,
701 				    const struct crypto_type *frontend,
702 				    u32 type, u32 mask)
703 {
704 	const char *name;
705 	int err;
706 
707 	name = crypto_attr_alg_name(rta);
708 	err = PTR_ERR(name);
709 	if (IS_ERR(name))
710 		return ERR_PTR(err);
711 
712 	return crypto_find_alg(name, frontend, type, mask);
713 }
714 EXPORT_SYMBOL_GPL(crypto_attr_alg2);
715 
716 int crypto_attr_u32(struct rtattr *rta, u32 *num)
717 {
718 	struct crypto_attr_u32 *nu32;
719 
720 	if (!rta)
721 		return -ENOENT;
722 	if (RTA_PAYLOAD(rta) < sizeof(*nu32))
723 		return -EINVAL;
724 	if (rta->rta_type != CRYPTOA_U32)
725 		return -EINVAL;
726 
727 	nu32 = RTA_DATA(rta);
728 	*num = nu32->num;
729 
730 	return 0;
731 }
732 EXPORT_SYMBOL_GPL(crypto_attr_u32);
733 
734 void *crypto_alloc_instance2(const char *name, struct crypto_alg *alg,
735 			     unsigned int head)
736 {
737 	struct crypto_instance *inst;
738 	char *p;
739 	int err;
740 
741 	p = kzalloc(head + sizeof(*inst) + sizeof(struct crypto_spawn),
742 		    GFP_KERNEL);
743 	if (!p)
744 		return ERR_PTR(-ENOMEM);
745 
746 	inst = (void *)(p + head);
747 
748 	err = -ENAMETOOLONG;
749 	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
750 		     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
751 		goto err_free_inst;
752 
753 	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
754 		     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
755 		goto err_free_inst;
756 
757 	return p;
758 
759 err_free_inst:
760 	kfree(p);
761 	return ERR_PTR(err);
762 }
763 EXPORT_SYMBOL_GPL(crypto_alloc_instance2);
764 
765 struct crypto_instance *crypto_alloc_instance(const char *name,
766 					      struct crypto_alg *alg)
767 {
768 	struct crypto_instance *inst;
769 	struct crypto_spawn *spawn;
770 	int err;
771 
772 	inst = crypto_alloc_instance2(name, alg, 0);
773 	if (IS_ERR(inst))
774 		goto out;
775 
776 	spawn = crypto_instance_ctx(inst);
777 	err = crypto_init_spawn(spawn, alg, inst,
778 				CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
779 
780 	if (err)
781 		goto err_free_inst;
782 
783 	return inst;
784 
785 err_free_inst:
786 	kfree(inst);
787 	inst = ERR_PTR(err);
788 
789 out:
790 	return inst;
791 }
792 EXPORT_SYMBOL_GPL(crypto_alloc_instance);
793 
794 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
795 {
796 	INIT_LIST_HEAD(&queue->list);
797 	queue->backlog = &queue->list;
798 	queue->qlen = 0;
799 	queue->max_qlen = max_qlen;
800 }
801 EXPORT_SYMBOL_GPL(crypto_init_queue);
802 
803 int crypto_enqueue_request(struct crypto_queue *queue,
804 			   struct crypto_async_request *request)
805 {
806 	int err = -EINPROGRESS;
807 
808 	if (unlikely(queue->qlen >= queue->max_qlen)) {
809 		err = -EBUSY;
810 		if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))
811 			goto out;
812 		if (queue->backlog == &queue->list)
813 			queue->backlog = &request->list;
814 	}
815 
816 	queue->qlen++;
817 	list_add_tail(&request->list, &queue->list);
818 
819 out:
820 	return err;
821 }
822 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
823 
824 void *__crypto_dequeue_request(struct crypto_queue *queue, unsigned int offset)
825 {
826 	struct list_head *request;
827 
828 	if (unlikely(!queue->qlen))
829 		return NULL;
830 
831 	queue->qlen--;
832 
833 	if (queue->backlog != &queue->list)
834 		queue->backlog = queue->backlog->next;
835 
836 	request = queue->list.next;
837 	list_del(request);
838 
839 	return (char *)list_entry(request, struct crypto_async_request, list) -
840 	       offset;
841 }
842 EXPORT_SYMBOL_GPL(__crypto_dequeue_request);
843 
844 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
845 {
846 	return __crypto_dequeue_request(queue, 0);
847 }
848 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
849 
850 int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
851 {
852 	struct crypto_async_request *req;
853 
854 	list_for_each_entry(req, &queue->list, list) {
855 		if (req->tfm == tfm)
856 			return 1;
857 	}
858 
859 	return 0;
860 }
861 EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
862 
863 static inline void crypto_inc_byte(u8 *a, unsigned int size)
864 {
865 	u8 *b = (a + size);
866 	u8 c;
867 
868 	for (; size; size--) {
869 		c = *--b + 1;
870 		*b = c;
871 		if (c)
872 			break;
873 	}
874 }
875 
876 void crypto_inc(u8 *a, unsigned int size)
877 {
878 	__be32 *b = (__be32 *)(a + size);
879 	u32 c;
880 
881 	for (; size >= 4; size -= 4) {
882 		c = be32_to_cpu(*--b) + 1;
883 		*b = cpu_to_be32(c);
884 		if (c)
885 			return;
886 	}
887 
888 	crypto_inc_byte(a, size);
889 }
890 EXPORT_SYMBOL_GPL(crypto_inc);
891 
892 static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size)
893 {
894 	for (; size; size--)
895 		*a++ ^= *b++;
896 }
897 
898 void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
899 {
900 	u32 *a = (u32 *)dst;
901 	u32 *b = (u32 *)src;
902 
903 	for (; size >= 4; size -= 4)
904 		*a++ ^= *b++;
905 
906 	crypto_xor_byte((u8 *)a, (u8 *)b, size);
907 }
908 EXPORT_SYMBOL_GPL(crypto_xor);
909 
910 static int __init crypto_algapi_init(void)
911 {
912 	crypto_init_proc();
913 	return 0;
914 }
915 
916 static void __exit crypto_algapi_exit(void)
917 {
918 	crypto_exit_proc();
919 }
920 
921 module_init(crypto_algapi_init);
922 module_exit(crypto_algapi_exit);
923 
924 MODULE_LICENSE("GPL");
925 MODULE_DESCRIPTION("Cryptographic algorithms API");
926