xref: /linux/crypto/algapi.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 	atomic_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 	if (list_empty(stack))
97 		return NULL;
98 
99 	spawn = list_first_entry(stack, struct crypto_spawn, list);
100 	n = list_entry(spawn->list.next, struct crypto_spawn, list);
101 
102 	if (spawn->alg && &n->list != stack && !n->alg)
103 		n->alg = (n->list.next == stack) ? alg :
104 			 &list_entry(n->list.next, struct crypto_spawn,
105 				     list)->inst->alg;
106 
107 	list_move(&spawn->list, secondary_spawns);
108 
109 	return &n->list == stack ? top : &n->inst->alg.cra_users;
110 }
111 
112 static void crypto_remove_instance(struct crypto_instance *inst,
113 				   struct list_head *list)
114 {
115 	struct crypto_template *tmpl = inst->tmpl;
116 
117 	if (crypto_is_dead(&inst->alg))
118 		return;
119 
120 	inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
121 	if (hlist_unhashed(&inst->list))
122 		return;
123 
124 	if (!tmpl || !crypto_tmpl_get(tmpl))
125 		return;
126 
127 	crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, &inst->alg);
128 	list_move(&inst->alg.cra_list, list);
129 	hlist_del(&inst->list);
130 	inst->alg.cra_destroy = crypto_destroy_instance;
131 
132 	BUG_ON(!list_empty(&inst->alg.cra_users));
133 }
134 
135 void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
136 			  struct crypto_alg *nalg)
137 {
138 	u32 new_type = (nalg ?: alg)->cra_flags;
139 	struct crypto_spawn *spawn, *n;
140 	LIST_HEAD(secondary_spawns);
141 	struct list_head *spawns;
142 	LIST_HEAD(stack);
143 	LIST_HEAD(top);
144 
145 	spawns = &alg->cra_users;
146 	list_for_each_entry_safe(spawn, n, spawns, list) {
147 		if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
148 			continue;
149 
150 		list_move(&spawn->list, &top);
151 	}
152 
153 	spawns = &top;
154 	do {
155 		while (!list_empty(spawns)) {
156 			struct crypto_instance *inst;
157 
158 			spawn = list_first_entry(spawns, struct crypto_spawn,
159 						 list);
160 			inst = spawn->inst;
161 
162 			BUG_ON(&inst->alg == alg);
163 
164 			list_move(&spawn->list, &stack);
165 
166 			if (&inst->alg == nalg)
167 				break;
168 
169 			spawn->alg = NULL;
170 			spawns = &inst->alg.cra_users;
171 		}
172 	} while ((spawns = crypto_more_spawns(alg, &stack, &top,
173 					      &secondary_spawns)));
174 
175 	list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
176 		if (spawn->alg)
177 			list_move(&spawn->list, &spawn->alg->cra_users);
178 		else
179 			crypto_remove_instance(spawn->inst, list);
180 	}
181 }
182 EXPORT_SYMBOL_GPL(crypto_remove_spawns);
183 
184 static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
185 {
186 	struct crypto_alg *q;
187 	struct crypto_larval *larval;
188 	int ret = -EAGAIN;
189 
190 	if (crypto_is_dead(alg))
191 		goto err;
192 
193 	INIT_LIST_HEAD(&alg->cra_users);
194 
195 	/* No cheating! */
196 	alg->cra_flags &= ~CRYPTO_ALG_TESTED;
197 
198 	ret = -EEXIST;
199 
200 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
201 		if (q == alg)
202 			goto err;
203 
204 		if (crypto_is_moribund(q))
205 			continue;
206 
207 		if (crypto_is_larval(q)) {
208 			if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
209 				goto err;
210 			continue;
211 		}
212 
213 		if (!strcmp(q->cra_driver_name, alg->cra_name) ||
214 		    !strcmp(q->cra_name, alg->cra_driver_name))
215 			goto err;
216 	}
217 
218 	larval = crypto_larval_alloc(alg->cra_name,
219 				     alg->cra_flags | CRYPTO_ALG_TESTED, 0);
220 	if (IS_ERR(larval))
221 		goto out;
222 
223 	ret = -ENOENT;
224 	larval->adult = crypto_mod_get(alg);
225 	if (!larval->adult)
226 		goto free_larval;
227 
228 	atomic_set(&larval->alg.cra_refcnt, 1);
229 	memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
230 	       CRYPTO_MAX_ALG_NAME);
231 	larval->alg.cra_priority = alg->cra_priority;
232 
233 	list_add(&alg->cra_list, &crypto_alg_list);
234 	list_add(&larval->alg.cra_list, &crypto_alg_list);
235 
236 out:
237 	return larval;
238 
239 free_larval:
240 	kfree(larval);
241 err:
242 	larval = ERR_PTR(ret);
243 	goto out;
244 }
245 
246 void crypto_alg_tested(const char *name, int err)
247 {
248 	struct crypto_larval *test;
249 	struct crypto_alg *alg;
250 	struct crypto_alg *q;
251 	LIST_HEAD(list);
252 
253 	down_write(&crypto_alg_sem);
254 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
255 		if (crypto_is_moribund(q) || !crypto_is_larval(q))
256 			continue;
257 
258 		test = (struct crypto_larval *)q;
259 
260 		if (!strcmp(q->cra_driver_name, name))
261 			goto found;
262 	}
263 
264 	printk(KERN_ERR "alg: Unexpected test result for %s: %d\n", name, err);
265 	goto unlock;
266 
267 found:
268 	q->cra_flags |= CRYPTO_ALG_DEAD;
269 	alg = test->adult;
270 	if (err || list_empty(&alg->cra_list))
271 		goto complete;
272 
273 	alg->cra_flags |= CRYPTO_ALG_TESTED;
274 
275 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
276 		if (q == alg)
277 			continue;
278 
279 		if (crypto_is_moribund(q))
280 			continue;
281 
282 		if (crypto_is_larval(q)) {
283 			struct crypto_larval *larval = (void *)q;
284 
285 			/*
286 			 * Check to see if either our generic name or
287 			 * specific name can satisfy the name requested
288 			 * by the larval entry q.
289 			 */
290 			if (strcmp(alg->cra_name, q->cra_name) &&
291 			    strcmp(alg->cra_driver_name, q->cra_name))
292 				continue;
293 
294 			if (larval->adult)
295 				continue;
296 			if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
297 				continue;
298 			if (!crypto_mod_get(alg))
299 				continue;
300 
301 			larval->adult = alg;
302 			continue;
303 		}
304 
305 		if (strcmp(alg->cra_name, q->cra_name))
306 			continue;
307 
308 		if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
309 		    q->cra_priority > alg->cra_priority)
310 			continue;
311 
312 		crypto_remove_spawns(q, &list, alg);
313 	}
314 
315 complete:
316 	complete_all(&test->completion);
317 
318 unlock:
319 	up_write(&crypto_alg_sem);
320 
321 	crypto_remove_final(&list);
322 }
323 EXPORT_SYMBOL_GPL(crypto_alg_tested);
324 
325 void crypto_remove_final(struct list_head *list)
326 {
327 	struct crypto_alg *alg;
328 	struct crypto_alg *n;
329 
330 	list_for_each_entry_safe(alg, n, list, cra_list) {
331 		list_del_init(&alg->cra_list);
332 		crypto_alg_put(alg);
333 	}
334 }
335 EXPORT_SYMBOL_GPL(crypto_remove_final);
336 
337 static void crypto_wait_for_test(struct crypto_larval *larval)
338 {
339 	int err;
340 
341 	err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
342 	if (err != NOTIFY_STOP) {
343 		if (WARN_ON(err != NOTIFY_DONE))
344 			goto out;
345 		crypto_alg_tested(larval->alg.cra_driver_name, 0);
346 	}
347 
348 	err = wait_for_completion_killable(&larval->completion);
349 	WARN_ON(err);
350 
351 out:
352 	crypto_larval_kill(&larval->alg);
353 }
354 
355 int crypto_register_alg(struct crypto_alg *alg)
356 {
357 	struct crypto_larval *larval;
358 	int err;
359 
360 	err = crypto_check_alg(alg);
361 	if (err)
362 		return err;
363 
364 	down_write(&crypto_alg_sem);
365 	larval = __crypto_register_alg(alg);
366 	up_write(&crypto_alg_sem);
367 
368 	if (IS_ERR(larval))
369 		return PTR_ERR(larval);
370 
371 	crypto_wait_for_test(larval);
372 	return 0;
373 }
374 EXPORT_SYMBOL_GPL(crypto_register_alg);
375 
376 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
377 {
378 	if (unlikely(list_empty(&alg->cra_list)))
379 		return -ENOENT;
380 
381 	alg->cra_flags |= CRYPTO_ALG_DEAD;
382 
383 	crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
384 	list_del_init(&alg->cra_list);
385 	crypto_remove_spawns(alg, list, NULL);
386 
387 	return 0;
388 }
389 
390 int crypto_unregister_alg(struct crypto_alg *alg)
391 {
392 	int ret;
393 	LIST_HEAD(list);
394 
395 	down_write(&crypto_alg_sem);
396 	ret = crypto_remove_alg(alg, &list);
397 	up_write(&crypto_alg_sem);
398 
399 	if (ret)
400 		return ret;
401 
402 	BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
403 	if (alg->cra_destroy)
404 		alg->cra_destroy(alg);
405 
406 	crypto_remove_final(&list);
407 	return 0;
408 }
409 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
410 
411 int crypto_register_algs(struct crypto_alg *algs, int count)
412 {
413 	int i, ret;
414 
415 	for (i = 0; i < count; i++) {
416 		ret = crypto_register_alg(&algs[i]);
417 		if (ret)
418 			goto err;
419 	}
420 
421 	return 0;
422 
423 err:
424 	for (--i; i >= 0; --i)
425 		crypto_unregister_alg(&algs[i]);
426 
427 	return ret;
428 }
429 EXPORT_SYMBOL_GPL(crypto_register_algs);
430 
431 int crypto_unregister_algs(struct crypto_alg *algs, int count)
432 {
433 	int i, ret;
434 
435 	for (i = 0; i < count; i++) {
436 		ret = crypto_unregister_alg(&algs[i]);
437 		if (ret)
438 			pr_err("Failed to unregister %s %s: %d\n",
439 			       algs[i].cra_driver_name, algs[i].cra_name, ret);
440 	}
441 
442 	return 0;
443 }
444 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
445 
446 int crypto_register_template(struct crypto_template *tmpl)
447 {
448 	struct crypto_template *q;
449 	int err = -EEXIST;
450 
451 	down_write(&crypto_alg_sem);
452 
453 	crypto_check_module_sig(tmpl->module);
454 
455 	list_for_each_entry(q, &crypto_template_list, list) {
456 		if (q == tmpl)
457 			goto out;
458 	}
459 
460 	list_add(&tmpl->list, &crypto_template_list);
461 	crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl);
462 	err = 0;
463 out:
464 	up_write(&crypto_alg_sem);
465 	return err;
466 }
467 EXPORT_SYMBOL_GPL(crypto_register_template);
468 
469 void crypto_unregister_template(struct crypto_template *tmpl)
470 {
471 	struct crypto_instance *inst;
472 	struct hlist_node *n;
473 	struct hlist_head *list;
474 	LIST_HEAD(users);
475 
476 	down_write(&crypto_alg_sem);
477 
478 	BUG_ON(list_empty(&tmpl->list));
479 	list_del_init(&tmpl->list);
480 
481 	list = &tmpl->instances;
482 	hlist_for_each_entry(inst, list, list) {
483 		int err = crypto_remove_alg(&inst->alg, &users);
484 
485 		BUG_ON(err);
486 	}
487 
488 	crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl);
489 
490 	up_write(&crypto_alg_sem);
491 
492 	hlist_for_each_entry_safe(inst, n, list, list) {
493 		BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1);
494 		crypto_free_instance(inst);
495 	}
496 	crypto_remove_final(&users);
497 }
498 EXPORT_SYMBOL_GPL(crypto_unregister_template);
499 
500 static struct crypto_template *__crypto_lookup_template(const char *name)
501 {
502 	struct crypto_template *q, *tmpl = NULL;
503 
504 	down_read(&crypto_alg_sem);
505 	list_for_each_entry(q, &crypto_template_list, list) {
506 		if (strcmp(q->name, name))
507 			continue;
508 		if (unlikely(!crypto_tmpl_get(q)))
509 			continue;
510 
511 		tmpl = q;
512 		break;
513 	}
514 	up_read(&crypto_alg_sem);
515 
516 	return tmpl;
517 }
518 
519 struct crypto_template *crypto_lookup_template(const char *name)
520 {
521 	return try_then_request_module(__crypto_lookup_template(name),
522 				       "crypto-%s", name);
523 }
524 EXPORT_SYMBOL_GPL(crypto_lookup_template);
525 
526 int crypto_register_instance(struct crypto_template *tmpl,
527 			     struct crypto_instance *inst)
528 {
529 	struct crypto_larval *larval;
530 	int err;
531 
532 	err = crypto_check_alg(&inst->alg);
533 	if (err)
534 		return err;
535 
536 	inst->alg.cra_module = tmpl->module;
537 	inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
538 
539 	if (unlikely(!crypto_mod_get(&inst->alg)))
540 		return -EAGAIN;
541 
542 	down_write(&crypto_alg_sem);
543 
544 	larval = __crypto_register_alg(&inst->alg);
545 	if (IS_ERR(larval))
546 		goto unlock;
547 
548 	hlist_add_head(&inst->list, &tmpl->instances);
549 	inst->tmpl = tmpl;
550 
551 unlock:
552 	up_write(&crypto_alg_sem);
553 
554 	err = PTR_ERR(larval);
555 	if (IS_ERR(larval))
556 		goto err;
557 
558 	crypto_wait_for_test(larval);
559 
560 	/* Remove instance if test failed */
561 	if (!(inst->alg.cra_flags & CRYPTO_ALG_TESTED))
562 		crypto_unregister_instance(inst);
563 	err = 0;
564 
565 err:
566 	crypto_mod_put(&inst->alg);
567 	return err;
568 }
569 EXPORT_SYMBOL_GPL(crypto_register_instance);
570 
571 int crypto_unregister_instance(struct crypto_instance *inst)
572 {
573 	LIST_HEAD(list);
574 
575 	down_write(&crypto_alg_sem);
576 
577 	crypto_remove_spawns(&inst->alg, &list, NULL);
578 	crypto_remove_instance(inst, &list);
579 
580 	up_write(&crypto_alg_sem);
581 
582 	crypto_remove_final(&list);
583 
584 	return 0;
585 }
586 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
587 
588 int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
589 		      struct crypto_instance *inst, u32 mask)
590 {
591 	int err = -EAGAIN;
592 
593 	spawn->inst = inst;
594 	spawn->mask = mask;
595 
596 	down_write(&crypto_alg_sem);
597 	if (!crypto_is_moribund(alg)) {
598 		list_add(&spawn->list, &alg->cra_users);
599 		spawn->alg = alg;
600 		err = 0;
601 	}
602 	up_write(&crypto_alg_sem);
603 
604 	return err;
605 }
606 EXPORT_SYMBOL_GPL(crypto_init_spawn);
607 
608 int crypto_init_spawn2(struct crypto_spawn *spawn, struct crypto_alg *alg,
609 		       struct crypto_instance *inst,
610 		       const struct crypto_type *frontend)
611 {
612 	int err = -EINVAL;
613 
614 	if ((alg->cra_flags ^ frontend->type) & frontend->maskset)
615 		goto out;
616 
617 	spawn->frontend = frontend;
618 	err = crypto_init_spawn(spawn, alg, inst, frontend->maskset);
619 
620 out:
621 	return err;
622 }
623 EXPORT_SYMBOL_GPL(crypto_init_spawn2);
624 
625 int crypto_grab_spawn(struct crypto_spawn *spawn, const char *name,
626 		      u32 type, u32 mask)
627 {
628 	struct crypto_alg *alg;
629 	int err;
630 
631 	alg = crypto_find_alg(name, spawn->frontend, type, mask);
632 	if (IS_ERR(alg))
633 		return PTR_ERR(alg);
634 
635 	err = crypto_init_spawn(spawn, alg, spawn->inst, mask);
636 	crypto_mod_put(alg);
637 	return err;
638 }
639 EXPORT_SYMBOL_GPL(crypto_grab_spawn);
640 
641 void crypto_drop_spawn(struct crypto_spawn *spawn)
642 {
643 	if (!spawn->alg)
644 		return;
645 
646 	down_write(&crypto_alg_sem);
647 	list_del(&spawn->list);
648 	up_write(&crypto_alg_sem);
649 }
650 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
651 
652 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
653 {
654 	struct crypto_alg *alg;
655 	struct crypto_alg *alg2;
656 
657 	down_read(&crypto_alg_sem);
658 	alg = spawn->alg;
659 	alg2 = alg;
660 	if (alg2)
661 		alg2 = crypto_mod_get(alg2);
662 	up_read(&crypto_alg_sem);
663 
664 	if (!alg2) {
665 		if (alg)
666 			crypto_shoot_alg(alg);
667 		return ERR_PTR(-EAGAIN);
668 	}
669 
670 	return alg;
671 }
672 
673 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
674 				    u32 mask)
675 {
676 	struct crypto_alg *alg;
677 	struct crypto_tfm *tfm;
678 
679 	alg = crypto_spawn_alg(spawn);
680 	if (IS_ERR(alg))
681 		return ERR_CAST(alg);
682 
683 	tfm = ERR_PTR(-EINVAL);
684 	if (unlikely((alg->cra_flags ^ type) & mask))
685 		goto out_put_alg;
686 
687 	tfm = __crypto_alloc_tfm(alg, type, mask);
688 	if (IS_ERR(tfm))
689 		goto out_put_alg;
690 
691 	return tfm;
692 
693 out_put_alg:
694 	crypto_mod_put(alg);
695 	return tfm;
696 }
697 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
698 
699 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
700 {
701 	struct crypto_alg *alg;
702 	struct crypto_tfm *tfm;
703 
704 	alg = crypto_spawn_alg(spawn);
705 	if (IS_ERR(alg))
706 		return ERR_CAST(alg);
707 
708 	tfm = crypto_create_tfm(alg, spawn->frontend);
709 	if (IS_ERR(tfm))
710 		goto out_put_alg;
711 
712 	return tfm;
713 
714 out_put_alg:
715 	crypto_mod_put(alg);
716 	return tfm;
717 }
718 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
719 
720 int crypto_register_notifier(struct notifier_block *nb)
721 {
722 	return blocking_notifier_chain_register(&crypto_chain, nb);
723 }
724 EXPORT_SYMBOL_GPL(crypto_register_notifier);
725 
726 int crypto_unregister_notifier(struct notifier_block *nb)
727 {
728 	return blocking_notifier_chain_unregister(&crypto_chain, nb);
729 }
730 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
731 
732 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
733 {
734 	struct rtattr *rta = tb[0];
735 	struct crypto_attr_type *algt;
736 
737 	if (!rta)
738 		return ERR_PTR(-ENOENT);
739 	if (RTA_PAYLOAD(rta) < sizeof(*algt))
740 		return ERR_PTR(-EINVAL);
741 	if (rta->rta_type != CRYPTOA_TYPE)
742 		return ERR_PTR(-EINVAL);
743 
744 	algt = RTA_DATA(rta);
745 
746 	return algt;
747 }
748 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
749 
750 int crypto_check_attr_type(struct rtattr **tb, u32 type)
751 {
752 	struct crypto_attr_type *algt;
753 
754 	algt = crypto_get_attr_type(tb);
755 	if (IS_ERR(algt))
756 		return PTR_ERR(algt);
757 
758 	if ((algt->type ^ type) & algt->mask)
759 		return -EINVAL;
760 
761 	return 0;
762 }
763 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
764 
765 const char *crypto_attr_alg_name(struct rtattr *rta)
766 {
767 	struct crypto_attr_alg *alga;
768 
769 	if (!rta)
770 		return ERR_PTR(-ENOENT);
771 	if (RTA_PAYLOAD(rta) < sizeof(*alga))
772 		return ERR_PTR(-EINVAL);
773 	if (rta->rta_type != CRYPTOA_ALG)
774 		return ERR_PTR(-EINVAL);
775 
776 	alga = RTA_DATA(rta);
777 	alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
778 
779 	return alga->name;
780 }
781 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
782 
783 struct crypto_alg *crypto_attr_alg2(struct rtattr *rta,
784 				    const struct crypto_type *frontend,
785 				    u32 type, u32 mask)
786 {
787 	const char *name;
788 
789 	name = crypto_attr_alg_name(rta);
790 	if (IS_ERR(name))
791 		return ERR_CAST(name);
792 
793 	return crypto_find_alg(name, frontend, type, mask);
794 }
795 EXPORT_SYMBOL_GPL(crypto_attr_alg2);
796 
797 int crypto_attr_u32(struct rtattr *rta, u32 *num)
798 {
799 	struct crypto_attr_u32 *nu32;
800 
801 	if (!rta)
802 		return -ENOENT;
803 	if (RTA_PAYLOAD(rta) < sizeof(*nu32))
804 		return -EINVAL;
805 	if (rta->rta_type != CRYPTOA_U32)
806 		return -EINVAL;
807 
808 	nu32 = RTA_DATA(rta);
809 	*num = nu32->num;
810 
811 	return 0;
812 }
813 EXPORT_SYMBOL_GPL(crypto_attr_u32);
814 
815 void *crypto_alloc_instance2(const char *name, struct crypto_alg *alg,
816 			     unsigned int head)
817 {
818 	struct crypto_instance *inst;
819 	char *p;
820 	int err;
821 
822 	p = kzalloc(head + sizeof(*inst) + sizeof(struct crypto_spawn),
823 		    GFP_KERNEL);
824 	if (!p)
825 		return ERR_PTR(-ENOMEM);
826 
827 	inst = (void *)(p + head);
828 
829 	err = -ENAMETOOLONG;
830 	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
831 		     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
832 		goto err_free_inst;
833 
834 	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
835 		     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
836 		goto err_free_inst;
837 
838 	return p;
839 
840 err_free_inst:
841 	kfree(p);
842 	return ERR_PTR(err);
843 }
844 EXPORT_SYMBOL_GPL(crypto_alloc_instance2);
845 
846 struct crypto_instance *crypto_alloc_instance(const char *name,
847 					      struct crypto_alg *alg)
848 {
849 	struct crypto_instance *inst;
850 	struct crypto_spawn *spawn;
851 	int err;
852 
853 	inst = crypto_alloc_instance2(name, alg, 0);
854 	if (IS_ERR(inst))
855 		goto out;
856 
857 	spawn = crypto_instance_ctx(inst);
858 	err = crypto_init_spawn(spawn, alg, inst,
859 				CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
860 
861 	if (err)
862 		goto err_free_inst;
863 
864 	return inst;
865 
866 err_free_inst:
867 	kfree(inst);
868 	inst = ERR_PTR(err);
869 
870 out:
871 	return inst;
872 }
873 EXPORT_SYMBOL_GPL(crypto_alloc_instance);
874 
875 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
876 {
877 	INIT_LIST_HEAD(&queue->list);
878 	queue->backlog = &queue->list;
879 	queue->qlen = 0;
880 	queue->max_qlen = max_qlen;
881 }
882 EXPORT_SYMBOL_GPL(crypto_init_queue);
883 
884 int crypto_enqueue_request(struct crypto_queue *queue,
885 			   struct crypto_async_request *request)
886 {
887 	int err = -EINPROGRESS;
888 
889 	if (unlikely(queue->qlen >= queue->max_qlen)) {
890 		err = -EBUSY;
891 		if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))
892 			goto out;
893 		if (queue->backlog == &queue->list)
894 			queue->backlog = &request->list;
895 	}
896 
897 	queue->qlen++;
898 	list_add_tail(&request->list, &queue->list);
899 
900 out:
901 	return err;
902 }
903 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
904 
905 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
906 {
907 	struct list_head *request;
908 
909 	if (unlikely(!queue->qlen))
910 		return NULL;
911 
912 	queue->qlen--;
913 
914 	if (queue->backlog != &queue->list)
915 		queue->backlog = queue->backlog->next;
916 
917 	request = queue->list.next;
918 	list_del(request);
919 
920 	return list_entry(request, struct crypto_async_request, list);
921 }
922 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
923 
924 int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
925 {
926 	struct crypto_async_request *req;
927 
928 	list_for_each_entry(req, &queue->list, list) {
929 		if (req->tfm == tfm)
930 			return 1;
931 	}
932 
933 	return 0;
934 }
935 EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
936 
937 static inline void crypto_inc_byte(u8 *a, unsigned int size)
938 {
939 	u8 *b = (a + size);
940 	u8 c;
941 
942 	for (; size; size--) {
943 		c = *--b + 1;
944 		*b = c;
945 		if (c)
946 			break;
947 	}
948 }
949 
950 void crypto_inc(u8 *a, unsigned int size)
951 {
952 	__be32 *b = (__be32 *)(a + size);
953 	u32 c;
954 
955 	for (; size >= 4; size -= 4) {
956 		c = be32_to_cpu(*--b) + 1;
957 		*b = cpu_to_be32(c);
958 		if (c)
959 			return;
960 	}
961 
962 	crypto_inc_byte(a, size);
963 }
964 EXPORT_SYMBOL_GPL(crypto_inc);
965 
966 static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size)
967 {
968 	for (; size; size--)
969 		*a++ ^= *b++;
970 }
971 
972 void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
973 {
974 	u32 *a = (u32 *)dst;
975 	u32 *b = (u32 *)src;
976 
977 	for (; size >= 4; size -= 4)
978 		*a++ ^= *b++;
979 
980 	crypto_xor_byte((u8 *)a, (u8 *)b, size);
981 }
982 EXPORT_SYMBOL_GPL(crypto_xor);
983 
984 unsigned int crypto_alg_extsize(struct crypto_alg *alg)
985 {
986 	return alg->cra_ctxsize +
987 	       (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
988 }
989 EXPORT_SYMBOL_GPL(crypto_alg_extsize);
990 
991 static int __init crypto_algapi_init(void)
992 {
993 	crypto_init_proc();
994 	return 0;
995 }
996 
997 static void __exit crypto_algapi_exit(void)
998 {
999 	crypto_exit_proc();
1000 }
1001 
1002 module_init(crypto_algapi_init);
1003 module_exit(crypto_algapi_exit);
1004 
1005 MODULE_LICENSE("GPL");
1006 MODULE_DESCRIPTION("Cryptographic algorithms API");
1007