xref: /linux/crypto/algapi.c (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
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_destroy_instance(struct crypto_alg *alg)
71 {
72 	struct crypto_instance *inst = (void *)alg;
73 	struct crypto_template *tmpl = inst->tmpl;
74 
75 	tmpl->free(inst);
76 	crypto_tmpl_put(tmpl);
77 }
78 
79 static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
80 					    struct list_head *stack,
81 					    struct list_head *top,
82 					    struct list_head *secondary_spawns)
83 {
84 	struct crypto_spawn *spawn, *n;
85 
86 	if (list_empty(stack))
87 		return NULL;
88 
89 	spawn = list_first_entry(stack, struct crypto_spawn, list);
90 	n = list_entry(spawn->list.next, struct crypto_spawn, list);
91 
92 	if (spawn->alg && &n->list != stack && !n->alg)
93 		n->alg = (n->list.next == stack) ? alg :
94 			 &list_entry(n->list.next, struct crypto_spawn,
95 				     list)->inst->alg;
96 
97 	list_move(&spawn->list, secondary_spawns);
98 
99 	return &n->list == stack ? top : &n->inst->alg.cra_users;
100 }
101 
102 static void crypto_remove_instance(struct crypto_instance *inst,
103 				   struct list_head *list)
104 {
105 	struct crypto_template *tmpl = inst->tmpl;
106 
107 	if (crypto_is_dead(&inst->alg))
108 		return;
109 
110 	inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
111 	if (hlist_unhashed(&inst->list))
112 		return;
113 
114 	if (!tmpl || !crypto_tmpl_get(tmpl))
115 		return;
116 
117 	crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, &inst->alg);
118 	list_move(&inst->alg.cra_list, list);
119 	hlist_del(&inst->list);
120 	inst->alg.cra_destroy = crypto_destroy_instance;
121 
122 	BUG_ON(!list_empty(&inst->alg.cra_users));
123 }
124 
125 void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
126 			  struct crypto_alg *nalg)
127 {
128 	u32 new_type = (nalg ?: alg)->cra_flags;
129 	struct crypto_spawn *spawn, *n;
130 	LIST_HEAD(secondary_spawns);
131 	struct list_head *spawns;
132 	LIST_HEAD(stack);
133 	LIST_HEAD(top);
134 
135 	spawns = &alg->cra_users;
136 	list_for_each_entry_safe(spawn, n, spawns, list) {
137 		if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
138 			continue;
139 
140 		list_move(&spawn->list, &top);
141 	}
142 
143 	spawns = &top;
144 	do {
145 		while (!list_empty(spawns)) {
146 			struct crypto_instance *inst;
147 
148 			spawn = list_first_entry(spawns, struct crypto_spawn,
149 						 list);
150 			inst = spawn->inst;
151 
152 			BUG_ON(&inst->alg == alg);
153 
154 			list_move(&spawn->list, &stack);
155 
156 			if (&inst->alg == nalg)
157 				break;
158 
159 			spawn->alg = NULL;
160 			spawns = &inst->alg.cra_users;
161 		}
162 	} while ((spawns = crypto_more_spawns(alg, &stack, &top,
163 					      &secondary_spawns)));
164 
165 	list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
166 		if (spawn->alg)
167 			list_move(&spawn->list, &spawn->alg->cra_users);
168 		else
169 			crypto_remove_instance(spawn->inst, list);
170 	}
171 }
172 EXPORT_SYMBOL_GPL(crypto_remove_spawns);
173 
174 static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
175 {
176 	struct crypto_alg *q;
177 	struct crypto_larval *larval;
178 	int ret = -EAGAIN;
179 
180 	if (crypto_is_dead(alg))
181 		goto err;
182 
183 	INIT_LIST_HEAD(&alg->cra_users);
184 
185 	/* No cheating! */
186 	alg->cra_flags &= ~CRYPTO_ALG_TESTED;
187 
188 	ret = -EEXIST;
189 
190 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
191 		if (q == alg)
192 			goto err;
193 
194 		if (crypto_is_moribund(q))
195 			continue;
196 
197 		if (crypto_is_larval(q)) {
198 			if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
199 				goto err;
200 			continue;
201 		}
202 
203 		if (!strcmp(q->cra_driver_name, alg->cra_name) ||
204 		    !strcmp(q->cra_name, alg->cra_driver_name))
205 			goto err;
206 	}
207 
208 	larval = crypto_larval_alloc(alg->cra_name,
209 				     alg->cra_flags | CRYPTO_ALG_TESTED, 0);
210 	if (IS_ERR(larval))
211 		goto out;
212 
213 	ret = -ENOENT;
214 	larval->adult = crypto_mod_get(alg);
215 	if (!larval->adult)
216 		goto free_larval;
217 
218 	atomic_set(&larval->alg.cra_refcnt, 1);
219 	memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
220 	       CRYPTO_MAX_ALG_NAME);
221 	larval->alg.cra_priority = alg->cra_priority;
222 
223 	list_add(&alg->cra_list, &crypto_alg_list);
224 	list_add(&larval->alg.cra_list, &crypto_alg_list);
225 
226 out:
227 	return larval;
228 
229 free_larval:
230 	kfree(larval);
231 err:
232 	larval = ERR_PTR(ret);
233 	goto out;
234 }
235 
236 void crypto_alg_tested(const char *name, int err)
237 {
238 	struct crypto_larval *test;
239 	struct crypto_alg *alg;
240 	struct crypto_alg *q;
241 	LIST_HEAD(list);
242 
243 	down_write(&crypto_alg_sem);
244 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
245 		if (crypto_is_moribund(q) || !crypto_is_larval(q))
246 			continue;
247 
248 		test = (struct crypto_larval *)q;
249 
250 		if (!strcmp(q->cra_driver_name, name))
251 			goto found;
252 	}
253 
254 	printk(KERN_ERR "alg: Unexpected test result for %s: %d\n", name, err);
255 	goto unlock;
256 
257 found:
258 	q->cra_flags |= CRYPTO_ALG_DEAD;
259 	alg = test->adult;
260 	if (err || list_empty(&alg->cra_list))
261 		goto complete;
262 
263 	alg->cra_flags |= CRYPTO_ALG_TESTED;
264 
265 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
266 		if (q == alg)
267 			continue;
268 
269 		if (crypto_is_moribund(q))
270 			continue;
271 
272 		if (crypto_is_larval(q)) {
273 			struct crypto_larval *larval = (void *)q;
274 
275 			/*
276 			 * Check to see if either our generic name or
277 			 * specific name can satisfy the name requested
278 			 * by the larval entry q.
279 			 */
280 			if (strcmp(alg->cra_name, q->cra_name) &&
281 			    strcmp(alg->cra_driver_name, q->cra_name))
282 				continue;
283 
284 			if (larval->adult)
285 				continue;
286 			if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
287 				continue;
288 			if (!crypto_mod_get(alg))
289 				continue;
290 
291 			larval->adult = alg;
292 			continue;
293 		}
294 
295 		if (strcmp(alg->cra_name, q->cra_name))
296 			continue;
297 
298 		if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
299 		    q->cra_priority > alg->cra_priority)
300 			continue;
301 
302 		crypto_remove_spawns(q, &list, alg);
303 	}
304 
305 complete:
306 	complete_all(&test->completion);
307 
308 unlock:
309 	up_write(&crypto_alg_sem);
310 
311 	crypto_remove_final(&list);
312 }
313 EXPORT_SYMBOL_GPL(crypto_alg_tested);
314 
315 void crypto_remove_final(struct list_head *list)
316 {
317 	struct crypto_alg *alg;
318 	struct crypto_alg *n;
319 
320 	list_for_each_entry_safe(alg, n, list, cra_list) {
321 		list_del_init(&alg->cra_list);
322 		crypto_alg_put(alg);
323 	}
324 }
325 EXPORT_SYMBOL_GPL(crypto_remove_final);
326 
327 static void crypto_wait_for_test(struct crypto_larval *larval)
328 {
329 	int err;
330 
331 	err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
332 	if (err != NOTIFY_STOP) {
333 		if (WARN_ON(err != NOTIFY_DONE))
334 			goto out;
335 		crypto_alg_tested(larval->alg.cra_driver_name, 0);
336 	}
337 
338 	err = wait_for_completion_interruptible(&larval->completion);
339 	WARN_ON(err);
340 
341 out:
342 	crypto_larval_kill(&larval->alg);
343 }
344 
345 int crypto_register_alg(struct crypto_alg *alg)
346 {
347 	struct crypto_larval *larval;
348 	int err;
349 
350 	err = crypto_check_alg(alg);
351 	if (err)
352 		return err;
353 
354 	down_write(&crypto_alg_sem);
355 	larval = __crypto_register_alg(alg);
356 	up_write(&crypto_alg_sem);
357 
358 	if (IS_ERR(larval))
359 		return PTR_ERR(larval);
360 
361 	crypto_wait_for_test(larval);
362 	return 0;
363 }
364 EXPORT_SYMBOL_GPL(crypto_register_alg);
365 
366 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
367 {
368 	if (unlikely(list_empty(&alg->cra_list)))
369 		return -ENOENT;
370 
371 	alg->cra_flags |= CRYPTO_ALG_DEAD;
372 
373 	crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
374 	list_del_init(&alg->cra_list);
375 	crypto_remove_spawns(alg, list, NULL);
376 
377 	return 0;
378 }
379 
380 int crypto_unregister_alg(struct crypto_alg *alg)
381 {
382 	int ret;
383 	LIST_HEAD(list);
384 
385 	down_write(&crypto_alg_sem);
386 	ret = crypto_remove_alg(alg, &list);
387 	up_write(&crypto_alg_sem);
388 
389 	if (ret)
390 		return ret;
391 
392 	BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
393 	if (alg->cra_destroy)
394 		alg->cra_destroy(alg);
395 
396 	crypto_remove_final(&list);
397 	return 0;
398 }
399 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
400 
401 int crypto_register_algs(struct crypto_alg *algs, int count)
402 {
403 	int i, ret;
404 
405 	for (i = 0; i < count; i++) {
406 		ret = crypto_register_alg(&algs[i]);
407 		if (ret)
408 			goto err;
409 	}
410 
411 	return 0;
412 
413 err:
414 	for (--i; i >= 0; --i)
415 		crypto_unregister_alg(&algs[i]);
416 
417 	return ret;
418 }
419 EXPORT_SYMBOL_GPL(crypto_register_algs);
420 
421 int crypto_unregister_algs(struct crypto_alg *algs, int count)
422 {
423 	int i, ret;
424 
425 	for (i = 0; i < count; i++) {
426 		ret = crypto_unregister_alg(&algs[i]);
427 		if (ret)
428 			pr_err("Failed to unregister %s %s: %d\n",
429 			       algs[i].cra_driver_name, algs[i].cra_name, ret);
430 	}
431 
432 	return 0;
433 }
434 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
435 
436 int crypto_register_template(struct crypto_template *tmpl)
437 {
438 	struct crypto_template *q;
439 	int err = -EEXIST;
440 
441 	down_write(&crypto_alg_sem);
442 
443 	crypto_check_module_sig(tmpl->module);
444 
445 	list_for_each_entry(q, &crypto_template_list, list) {
446 		if (q == tmpl)
447 			goto out;
448 	}
449 
450 	list_add(&tmpl->list, &crypto_template_list);
451 	crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl);
452 	err = 0;
453 out:
454 	up_write(&crypto_alg_sem);
455 	return err;
456 }
457 EXPORT_SYMBOL_GPL(crypto_register_template);
458 
459 void crypto_unregister_template(struct crypto_template *tmpl)
460 {
461 	struct crypto_instance *inst;
462 	struct hlist_node *n;
463 	struct hlist_head *list;
464 	LIST_HEAD(users);
465 
466 	down_write(&crypto_alg_sem);
467 
468 	BUG_ON(list_empty(&tmpl->list));
469 	list_del_init(&tmpl->list);
470 
471 	list = &tmpl->instances;
472 	hlist_for_each_entry(inst, list, list) {
473 		int err = crypto_remove_alg(&inst->alg, &users);
474 
475 		BUG_ON(err);
476 	}
477 
478 	crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl);
479 
480 	up_write(&crypto_alg_sem);
481 
482 	hlist_for_each_entry_safe(inst, n, list, list) {
483 		BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1);
484 		tmpl->free(inst);
485 	}
486 	crypto_remove_final(&users);
487 }
488 EXPORT_SYMBOL_GPL(crypto_unregister_template);
489 
490 static struct crypto_template *__crypto_lookup_template(const char *name)
491 {
492 	struct crypto_template *q, *tmpl = NULL;
493 
494 	down_read(&crypto_alg_sem);
495 	list_for_each_entry(q, &crypto_template_list, list) {
496 		if (strcmp(q->name, name))
497 			continue;
498 		if (unlikely(!crypto_tmpl_get(q)))
499 			continue;
500 
501 		tmpl = q;
502 		break;
503 	}
504 	up_read(&crypto_alg_sem);
505 
506 	return tmpl;
507 }
508 
509 struct crypto_template *crypto_lookup_template(const char *name)
510 {
511 	return try_then_request_module(__crypto_lookup_template(name),
512 				       "crypto-%s", name);
513 }
514 EXPORT_SYMBOL_GPL(crypto_lookup_template);
515 
516 int crypto_register_instance(struct crypto_template *tmpl,
517 			     struct crypto_instance *inst)
518 {
519 	struct crypto_larval *larval;
520 	int err;
521 
522 	err = crypto_check_alg(&inst->alg);
523 	if (err)
524 		return err;
525 
526 	inst->alg.cra_module = tmpl->module;
527 	inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
528 
529 	if (unlikely(!crypto_mod_get(&inst->alg)))
530 		return -EAGAIN;
531 
532 	down_write(&crypto_alg_sem);
533 
534 	larval = __crypto_register_alg(&inst->alg);
535 	if (IS_ERR(larval))
536 		goto unlock;
537 
538 	hlist_add_head(&inst->list, &tmpl->instances);
539 	inst->tmpl = tmpl;
540 
541 unlock:
542 	up_write(&crypto_alg_sem);
543 
544 	err = PTR_ERR(larval);
545 	if (IS_ERR(larval))
546 		goto err;
547 
548 	crypto_wait_for_test(larval);
549 
550 	/* Remove instance if test failed */
551 	if (!(inst->alg.cra_flags & CRYPTO_ALG_TESTED))
552 		crypto_unregister_instance(inst);
553 	err = 0;
554 
555 err:
556 	crypto_mod_put(&inst->alg);
557 	return err;
558 }
559 EXPORT_SYMBOL_GPL(crypto_register_instance);
560 
561 int crypto_unregister_instance(struct crypto_instance *inst)
562 {
563 	LIST_HEAD(list);
564 
565 	down_write(&crypto_alg_sem);
566 
567 	crypto_remove_spawns(&inst->alg, &list, NULL);
568 	crypto_remove_instance(inst, &list);
569 
570 	up_write(&crypto_alg_sem);
571 
572 	crypto_remove_final(&list);
573 
574 	return 0;
575 }
576 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
577 
578 int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
579 		      struct crypto_instance *inst, u32 mask)
580 {
581 	int err = -EAGAIN;
582 
583 	spawn->inst = inst;
584 	spawn->mask = mask;
585 
586 	down_write(&crypto_alg_sem);
587 	if (!crypto_is_moribund(alg)) {
588 		list_add(&spawn->list, &alg->cra_users);
589 		spawn->alg = alg;
590 		err = 0;
591 	}
592 	up_write(&crypto_alg_sem);
593 
594 	return err;
595 }
596 EXPORT_SYMBOL_GPL(crypto_init_spawn);
597 
598 int crypto_init_spawn2(struct crypto_spawn *spawn, struct crypto_alg *alg,
599 		       struct crypto_instance *inst,
600 		       const struct crypto_type *frontend)
601 {
602 	int err = -EINVAL;
603 
604 	if ((alg->cra_flags ^ frontend->type) & frontend->maskset)
605 		goto out;
606 
607 	spawn->frontend = frontend;
608 	err = crypto_init_spawn(spawn, alg, inst, frontend->maskset);
609 
610 out:
611 	return err;
612 }
613 EXPORT_SYMBOL_GPL(crypto_init_spawn2);
614 
615 int crypto_grab_spawn(struct crypto_spawn *spawn, const char *name,
616 		      u32 type, u32 mask)
617 {
618 	struct crypto_alg *alg;
619 	int err;
620 
621 	alg = crypto_find_alg(name, spawn->frontend, type, mask);
622 	if (IS_ERR(alg))
623 		return PTR_ERR(alg);
624 
625 	err = crypto_init_spawn(spawn, alg, spawn->inst, mask);
626 	crypto_mod_put(alg);
627 	return err;
628 }
629 EXPORT_SYMBOL_GPL(crypto_grab_spawn);
630 
631 void crypto_drop_spawn(struct crypto_spawn *spawn)
632 {
633 	if (!spawn->alg)
634 		return;
635 
636 	down_write(&crypto_alg_sem);
637 	list_del(&spawn->list);
638 	up_write(&crypto_alg_sem);
639 }
640 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
641 
642 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
643 {
644 	struct crypto_alg *alg;
645 	struct crypto_alg *alg2;
646 
647 	down_read(&crypto_alg_sem);
648 	alg = spawn->alg;
649 	alg2 = alg;
650 	if (alg2)
651 		alg2 = crypto_mod_get(alg2);
652 	up_read(&crypto_alg_sem);
653 
654 	if (!alg2) {
655 		if (alg)
656 			crypto_shoot_alg(alg);
657 		return ERR_PTR(-EAGAIN);
658 	}
659 
660 	return alg;
661 }
662 
663 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
664 				    u32 mask)
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 = ERR_PTR(-EINVAL);
674 	if (unlikely((alg->cra_flags ^ type) & mask))
675 		goto out_put_alg;
676 
677 	tfm = __crypto_alloc_tfm(alg, type, mask);
678 	if (IS_ERR(tfm))
679 		goto out_put_alg;
680 
681 	return tfm;
682 
683 out_put_alg:
684 	crypto_mod_put(alg);
685 	return tfm;
686 }
687 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
688 
689 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
690 {
691 	struct crypto_alg *alg;
692 	struct crypto_tfm *tfm;
693 
694 	alg = crypto_spawn_alg(spawn);
695 	if (IS_ERR(alg))
696 		return ERR_CAST(alg);
697 
698 	tfm = crypto_create_tfm(alg, spawn->frontend);
699 	if (IS_ERR(tfm))
700 		goto out_put_alg;
701 
702 	return tfm;
703 
704 out_put_alg:
705 	crypto_mod_put(alg);
706 	return tfm;
707 }
708 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
709 
710 int crypto_register_notifier(struct notifier_block *nb)
711 {
712 	return blocking_notifier_chain_register(&crypto_chain, nb);
713 }
714 EXPORT_SYMBOL_GPL(crypto_register_notifier);
715 
716 int crypto_unregister_notifier(struct notifier_block *nb)
717 {
718 	return blocking_notifier_chain_unregister(&crypto_chain, nb);
719 }
720 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
721 
722 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
723 {
724 	struct rtattr *rta = tb[0];
725 	struct crypto_attr_type *algt;
726 
727 	if (!rta)
728 		return ERR_PTR(-ENOENT);
729 	if (RTA_PAYLOAD(rta) < sizeof(*algt))
730 		return ERR_PTR(-EINVAL);
731 	if (rta->rta_type != CRYPTOA_TYPE)
732 		return ERR_PTR(-EINVAL);
733 
734 	algt = RTA_DATA(rta);
735 
736 	return algt;
737 }
738 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
739 
740 int crypto_check_attr_type(struct rtattr **tb, u32 type)
741 {
742 	struct crypto_attr_type *algt;
743 
744 	algt = crypto_get_attr_type(tb);
745 	if (IS_ERR(algt))
746 		return PTR_ERR(algt);
747 
748 	if ((algt->type ^ type) & algt->mask)
749 		return -EINVAL;
750 
751 	return 0;
752 }
753 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
754 
755 const char *crypto_attr_alg_name(struct rtattr *rta)
756 {
757 	struct crypto_attr_alg *alga;
758 
759 	if (!rta)
760 		return ERR_PTR(-ENOENT);
761 	if (RTA_PAYLOAD(rta) < sizeof(*alga))
762 		return ERR_PTR(-EINVAL);
763 	if (rta->rta_type != CRYPTOA_ALG)
764 		return ERR_PTR(-EINVAL);
765 
766 	alga = RTA_DATA(rta);
767 	alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
768 
769 	return alga->name;
770 }
771 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
772 
773 struct crypto_alg *crypto_attr_alg2(struct rtattr *rta,
774 				    const struct crypto_type *frontend,
775 				    u32 type, u32 mask)
776 {
777 	const char *name;
778 
779 	name = crypto_attr_alg_name(rta);
780 	if (IS_ERR(name))
781 		return ERR_CAST(name);
782 
783 	return crypto_find_alg(name, frontend, type, mask);
784 }
785 EXPORT_SYMBOL_GPL(crypto_attr_alg2);
786 
787 int crypto_attr_u32(struct rtattr *rta, u32 *num)
788 {
789 	struct crypto_attr_u32 *nu32;
790 
791 	if (!rta)
792 		return -ENOENT;
793 	if (RTA_PAYLOAD(rta) < sizeof(*nu32))
794 		return -EINVAL;
795 	if (rta->rta_type != CRYPTOA_U32)
796 		return -EINVAL;
797 
798 	nu32 = RTA_DATA(rta);
799 	*num = nu32->num;
800 
801 	return 0;
802 }
803 EXPORT_SYMBOL_GPL(crypto_attr_u32);
804 
805 void *crypto_alloc_instance2(const char *name, struct crypto_alg *alg,
806 			     unsigned int head)
807 {
808 	struct crypto_instance *inst;
809 	char *p;
810 	int err;
811 
812 	p = kzalloc(head + sizeof(*inst) + sizeof(struct crypto_spawn),
813 		    GFP_KERNEL);
814 	if (!p)
815 		return ERR_PTR(-ENOMEM);
816 
817 	inst = (void *)(p + head);
818 
819 	err = -ENAMETOOLONG;
820 	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
821 		     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
822 		goto err_free_inst;
823 
824 	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
825 		     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
826 		goto err_free_inst;
827 
828 	return p;
829 
830 err_free_inst:
831 	kfree(p);
832 	return ERR_PTR(err);
833 }
834 EXPORT_SYMBOL_GPL(crypto_alloc_instance2);
835 
836 struct crypto_instance *crypto_alloc_instance(const char *name,
837 					      struct crypto_alg *alg)
838 {
839 	struct crypto_instance *inst;
840 	struct crypto_spawn *spawn;
841 	int err;
842 
843 	inst = crypto_alloc_instance2(name, alg, 0);
844 	if (IS_ERR(inst))
845 		goto out;
846 
847 	spawn = crypto_instance_ctx(inst);
848 	err = crypto_init_spawn(spawn, alg, inst,
849 				CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
850 
851 	if (err)
852 		goto err_free_inst;
853 
854 	return inst;
855 
856 err_free_inst:
857 	kfree(inst);
858 	inst = ERR_PTR(err);
859 
860 out:
861 	return inst;
862 }
863 EXPORT_SYMBOL_GPL(crypto_alloc_instance);
864 
865 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
866 {
867 	INIT_LIST_HEAD(&queue->list);
868 	queue->backlog = &queue->list;
869 	queue->qlen = 0;
870 	queue->max_qlen = max_qlen;
871 }
872 EXPORT_SYMBOL_GPL(crypto_init_queue);
873 
874 int crypto_enqueue_request(struct crypto_queue *queue,
875 			   struct crypto_async_request *request)
876 {
877 	int err = -EINPROGRESS;
878 
879 	if (unlikely(queue->qlen >= queue->max_qlen)) {
880 		err = -EBUSY;
881 		if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))
882 			goto out;
883 		if (queue->backlog == &queue->list)
884 			queue->backlog = &request->list;
885 	}
886 
887 	queue->qlen++;
888 	list_add_tail(&request->list, &queue->list);
889 
890 out:
891 	return err;
892 }
893 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
894 
895 void *__crypto_dequeue_request(struct crypto_queue *queue, unsigned int offset)
896 {
897 	struct list_head *request;
898 
899 	if (unlikely(!queue->qlen))
900 		return NULL;
901 
902 	queue->qlen--;
903 
904 	if (queue->backlog != &queue->list)
905 		queue->backlog = queue->backlog->next;
906 
907 	request = queue->list.next;
908 	list_del(request);
909 
910 	return (char *)list_entry(request, struct crypto_async_request, list) -
911 	       offset;
912 }
913 EXPORT_SYMBOL_GPL(__crypto_dequeue_request);
914 
915 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
916 {
917 	return __crypto_dequeue_request(queue, 0);
918 }
919 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
920 
921 int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
922 {
923 	struct crypto_async_request *req;
924 
925 	list_for_each_entry(req, &queue->list, list) {
926 		if (req->tfm == tfm)
927 			return 1;
928 	}
929 
930 	return 0;
931 }
932 EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
933 
934 static inline void crypto_inc_byte(u8 *a, unsigned int size)
935 {
936 	u8 *b = (a + size);
937 	u8 c;
938 
939 	for (; size; size--) {
940 		c = *--b + 1;
941 		*b = c;
942 		if (c)
943 			break;
944 	}
945 }
946 
947 void crypto_inc(u8 *a, unsigned int size)
948 {
949 	__be32 *b = (__be32 *)(a + size);
950 	u32 c;
951 
952 	for (; size >= 4; size -= 4) {
953 		c = be32_to_cpu(*--b) + 1;
954 		*b = cpu_to_be32(c);
955 		if (c)
956 			return;
957 	}
958 
959 	crypto_inc_byte(a, size);
960 }
961 EXPORT_SYMBOL_GPL(crypto_inc);
962 
963 static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size)
964 {
965 	for (; size; size--)
966 		*a++ ^= *b++;
967 }
968 
969 void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
970 {
971 	u32 *a = (u32 *)dst;
972 	u32 *b = (u32 *)src;
973 
974 	for (; size >= 4; size -= 4)
975 		*a++ ^= *b++;
976 
977 	crypto_xor_byte((u8 *)a, (u8 *)b, size);
978 }
979 EXPORT_SYMBOL_GPL(crypto_xor);
980 
981 unsigned int crypto_alg_extsize(struct crypto_alg *alg)
982 {
983 	return alg->cra_ctxsize +
984 	       (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
985 }
986 EXPORT_SYMBOL_GPL(crypto_alg_extsize);
987 
988 static int __init crypto_algapi_init(void)
989 {
990 	crypto_init_proc();
991 	return 0;
992 }
993 
994 static void __exit crypto_algapi_exit(void)
995 {
996 	crypto_exit_proc();
997 }
998 
999 module_init(crypto_algapi_init);
1000 module_exit(crypto_algapi_exit);
1001 
1002 MODULE_LICENSE("GPL");
1003 MODULE_DESCRIPTION("Cryptographic algorithms API");
1004