xref: /openbmc/linux/crypto/algapi.c (revision 83394e7d)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Cryptographic API for algorithms (i.e., low-level API).
4  *
5  * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
6  */
7 
8 #include <crypto/algapi.h>
9 #include <crypto/internal/simd.h>
10 #include <linux/err.h>
11 #include <linux/errno.h>
12 #include <linux/fips.h>
13 #include <linux/init.h>
14 #include <linux/kernel.h>
15 #include <linux/list.h>
16 #include <linux/module.h>
17 #include <linux/rtnetlink.h>
18 #include <linux/slab.h>
19 #include <linux/string.h>
20 #include <linux/workqueue.h>
21 
22 #include "internal.h"
23 
24 static LIST_HEAD(crypto_template_list);
25 
26 #ifdef CONFIG_CRYPTO_MANAGER_EXTRA_TESTS
27 DEFINE_PER_CPU(bool, crypto_simd_disabled_for_test);
28 EXPORT_PER_CPU_SYMBOL_GPL(crypto_simd_disabled_for_test);
29 #endif
30 
crypto_check_module_sig(struct module * mod)31 static inline void crypto_check_module_sig(struct module *mod)
32 {
33 	if (fips_enabled && mod && !module_sig_ok(mod))
34 		panic("Module %s signature verification failed in FIPS mode\n",
35 		      module_name(mod));
36 }
37 
crypto_check_alg(struct crypto_alg * alg)38 static int crypto_check_alg(struct crypto_alg *alg)
39 {
40 	crypto_check_module_sig(alg->cra_module);
41 
42 	if (!alg->cra_name[0] || !alg->cra_driver_name[0])
43 		return -EINVAL;
44 
45 	if (alg->cra_alignmask & (alg->cra_alignmask + 1))
46 		return -EINVAL;
47 
48 	/* General maximums for all algs. */
49 	if (alg->cra_alignmask > MAX_ALGAPI_ALIGNMASK)
50 		return -EINVAL;
51 
52 	if (alg->cra_blocksize > MAX_ALGAPI_BLOCKSIZE)
53 		return -EINVAL;
54 
55 	/* Lower maximums for specific alg types. */
56 	if (!alg->cra_type && (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
57 			       CRYPTO_ALG_TYPE_CIPHER) {
58 		if (alg->cra_alignmask > MAX_CIPHER_ALIGNMASK)
59 			return -EINVAL;
60 
61 		if (alg->cra_blocksize > MAX_CIPHER_BLOCKSIZE)
62 			return -EINVAL;
63 	}
64 
65 	if (alg->cra_priority < 0)
66 		return -EINVAL;
67 
68 	refcount_set(&alg->cra_refcnt, 1);
69 
70 	return 0;
71 }
72 
crypto_free_instance(struct crypto_instance * inst)73 static void crypto_free_instance(struct crypto_instance *inst)
74 {
75 	inst->alg.cra_type->free(inst);
76 }
77 
crypto_destroy_instance_workfn(struct work_struct * w)78 static void crypto_destroy_instance_workfn(struct work_struct *w)
79 {
80 	struct crypto_instance *inst = container_of(w, struct crypto_instance,
81 						    free_work);
82 	struct crypto_template *tmpl = inst->tmpl;
83 
84 	crypto_free_instance(inst);
85 	crypto_tmpl_put(tmpl);
86 }
87 
crypto_destroy_instance(struct crypto_alg * alg)88 static void crypto_destroy_instance(struct crypto_alg *alg)
89 {
90 	struct crypto_instance *inst = container_of(alg,
91 						    struct crypto_instance,
92 						    alg);
93 
94 	INIT_WORK(&inst->free_work, crypto_destroy_instance_workfn);
95 	schedule_work(&inst->free_work);
96 }
97 
98 /*
99  * This function adds a spawn to the list secondary_spawns which
100  * will be used at the end of crypto_remove_spawns to unregister
101  * instances, unless the spawn happens to be one that is depended
102  * on by the new algorithm (nalg in crypto_remove_spawns).
103  *
104  * This function is also responsible for resurrecting any algorithms
105  * in the dependency chain of nalg by unsetting n->dead.
106  */
crypto_more_spawns(struct crypto_alg * alg,struct list_head * stack,struct list_head * top,struct list_head * secondary_spawns)107 static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
108 					    struct list_head *stack,
109 					    struct list_head *top,
110 					    struct list_head *secondary_spawns)
111 {
112 	struct crypto_spawn *spawn, *n;
113 
114 	spawn = list_first_entry_or_null(stack, struct crypto_spawn, list);
115 	if (!spawn)
116 		return NULL;
117 
118 	n = list_prev_entry(spawn, list);
119 	list_move(&spawn->list, secondary_spawns);
120 
121 	if (list_is_last(&n->list, stack))
122 		return top;
123 
124 	n = list_next_entry(n, list);
125 	if (!spawn->dead)
126 		n->dead = false;
127 
128 	return &n->inst->alg.cra_users;
129 }
130 
crypto_remove_instance(struct crypto_instance * inst,struct list_head * list)131 static void crypto_remove_instance(struct crypto_instance *inst,
132 				   struct list_head *list)
133 {
134 	struct crypto_template *tmpl = inst->tmpl;
135 
136 	if (crypto_is_dead(&inst->alg))
137 		return;
138 
139 	inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
140 
141 	if (!tmpl || !crypto_tmpl_get(tmpl))
142 		return;
143 
144 	list_move(&inst->alg.cra_list, list);
145 	hlist_del(&inst->list);
146 	inst->alg.cra_destroy = crypto_destroy_instance;
147 
148 	BUG_ON(!list_empty(&inst->alg.cra_users));
149 }
150 
151 /*
152  * Given an algorithm alg, remove all algorithms that depend on it
153  * through spawns.  If nalg is not null, then exempt any algorithms
154  * that is depended on by nalg.  This is useful when nalg itself
155  * depends on alg.
156  */
crypto_remove_spawns(struct crypto_alg * alg,struct list_head * list,struct crypto_alg * nalg)157 void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
158 			  struct crypto_alg *nalg)
159 {
160 	u32 new_type = (nalg ?: alg)->cra_flags;
161 	struct crypto_spawn *spawn, *n;
162 	LIST_HEAD(secondary_spawns);
163 	struct list_head *spawns;
164 	LIST_HEAD(stack);
165 	LIST_HEAD(top);
166 
167 	spawns = &alg->cra_users;
168 	list_for_each_entry_safe(spawn, n, spawns, list) {
169 		if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
170 			continue;
171 
172 		list_move(&spawn->list, &top);
173 	}
174 
175 	/*
176 	 * Perform a depth-first walk starting from alg through
177 	 * the cra_users tree.  The list stack records the path
178 	 * from alg to the current spawn.
179 	 */
180 	spawns = &top;
181 	do {
182 		while (!list_empty(spawns)) {
183 			struct crypto_instance *inst;
184 
185 			spawn = list_first_entry(spawns, struct crypto_spawn,
186 						 list);
187 			inst = spawn->inst;
188 
189 			list_move(&spawn->list, &stack);
190 			spawn->dead = !spawn->registered || &inst->alg != nalg;
191 
192 			if (!spawn->registered)
193 				break;
194 
195 			BUG_ON(&inst->alg == alg);
196 
197 			if (&inst->alg == nalg)
198 				break;
199 
200 			spawns = &inst->alg.cra_users;
201 
202 			/*
203 			 * Even if spawn->registered is true, the
204 			 * instance itself may still be unregistered.
205 			 * This is because it may have failed during
206 			 * registration.  Therefore we still need to
207 			 * make the following test.
208 			 *
209 			 * We may encounter an unregistered instance here, since
210 			 * an instance's spawns are set up prior to the instance
211 			 * being registered.  An unregistered instance will have
212 			 * NULL ->cra_users.next, since ->cra_users isn't
213 			 * properly initialized until registration.  But an
214 			 * unregistered instance cannot have any users, so treat
215 			 * it the same as ->cra_users being empty.
216 			 */
217 			if (spawns->next == NULL)
218 				break;
219 		}
220 	} while ((spawns = crypto_more_spawns(alg, &stack, &top,
221 					      &secondary_spawns)));
222 
223 	/*
224 	 * Remove all instances that are marked as dead.  Also
225 	 * complete the resurrection of the others by moving them
226 	 * back to the cra_users list.
227 	 */
228 	list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
229 		if (!spawn->dead)
230 			list_move(&spawn->list, &spawn->alg->cra_users);
231 		else if (spawn->registered)
232 			crypto_remove_instance(spawn->inst, list);
233 	}
234 }
235 EXPORT_SYMBOL_GPL(crypto_remove_spawns);
236 
crypto_alg_finish_registration(struct crypto_alg * alg,bool fulfill_requests,struct list_head * algs_to_put)237 static void crypto_alg_finish_registration(struct crypto_alg *alg,
238 					   bool fulfill_requests,
239 					   struct list_head *algs_to_put)
240 {
241 	struct crypto_alg *q;
242 
243 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
244 		if (q == alg)
245 			continue;
246 
247 		if (crypto_is_moribund(q))
248 			continue;
249 
250 		if (crypto_is_larval(q)) {
251 			struct crypto_larval *larval = (void *)q;
252 
253 			/*
254 			 * Check to see if either our generic name or
255 			 * specific name can satisfy the name requested
256 			 * by the larval entry q.
257 			 */
258 			if (strcmp(alg->cra_name, q->cra_name) &&
259 			    strcmp(alg->cra_driver_name, q->cra_name))
260 				continue;
261 
262 			if (larval->adult)
263 				continue;
264 			if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
265 				continue;
266 
267 			if (fulfill_requests && crypto_mod_get(alg))
268 				larval->adult = alg;
269 			else
270 				larval->adult = ERR_PTR(-EAGAIN);
271 
272 			continue;
273 		}
274 
275 		if (strcmp(alg->cra_name, q->cra_name))
276 			continue;
277 
278 		if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
279 		    q->cra_priority > alg->cra_priority)
280 			continue;
281 
282 		crypto_remove_spawns(q, algs_to_put, alg);
283 	}
284 
285 	crypto_notify(CRYPTO_MSG_ALG_LOADED, alg);
286 }
287 
crypto_alloc_test_larval(struct crypto_alg * alg)288 static struct crypto_larval *crypto_alloc_test_larval(struct crypto_alg *alg)
289 {
290 	struct crypto_larval *larval;
291 
292 	if (!IS_ENABLED(CONFIG_CRYPTO_MANAGER) ||
293 	    IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS) ||
294 	    (alg->cra_flags & CRYPTO_ALG_INTERNAL))
295 		return NULL; /* No self-test needed */
296 
297 	larval = crypto_larval_alloc(alg->cra_name,
298 				     alg->cra_flags | CRYPTO_ALG_TESTED, 0);
299 	if (IS_ERR(larval))
300 		return larval;
301 
302 	larval->adult = crypto_mod_get(alg);
303 	if (!larval->adult) {
304 		kfree(larval);
305 		return ERR_PTR(-ENOENT);
306 	}
307 
308 	refcount_set(&larval->alg.cra_refcnt, 1);
309 	memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
310 	       CRYPTO_MAX_ALG_NAME);
311 	larval->alg.cra_priority = alg->cra_priority;
312 
313 	return larval;
314 }
315 
316 static struct crypto_larval *
__crypto_register_alg(struct crypto_alg * alg,struct list_head * algs_to_put)317 __crypto_register_alg(struct crypto_alg *alg, struct list_head *algs_to_put)
318 {
319 	struct crypto_alg *q;
320 	struct crypto_larval *larval;
321 	int ret = -EAGAIN;
322 
323 	if (crypto_is_dead(alg))
324 		goto err;
325 
326 	INIT_LIST_HEAD(&alg->cra_users);
327 
328 	ret = -EEXIST;
329 
330 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
331 		if (q == alg)
332 			goto err;
333 
334 		if (crypto_is_moribund(q))
335 			continue;
336 
337 		if (crypto_is_larval(q)) {
338 			if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
339 				goto err;
340 			continue;
341 		}
342 
343 		if (!strcmp(q->cra_driver_name, alg->cra_name) ||
344 		    !strcmp(q->cra_driver_name, alg->cra_driver_name) ||
345 		    !strcmp(q->cra_name, alg->cra_driver_name))
346 			goto err;
347 	}
348 
349 	larval = crypto_alloc_test_larval(alg);
350 	if (IS_ERR(larval))
351 		goto out;
352 
353 	list_add(&alg->cra_list, &crypto_alg_list);
354 
355 	if (larval) {
356 		/* No cheating! */
357 		alg->cra_flags &= ~CRYPTO_ALG_TESTED;
358 
359 		list_add(&larval->alg.cra_list, &crypto_alg_list);
360 	} else {
361 		alg->cra_flags |= CRYPTO_ALG_TESTED;
362 		crypto_alg_finish_registration(alg, true, algs_to_put);
363 	}
364 
365 out:
366 	return larval;
367 
368 err:
369 	larval = ERR_PTR(ret);
370 	goto out;
371 }
372 
crypto_alg_tested(const char * name,int err)373 void crypto_alg_tested(const char *name, int err)
374 {
375 	struct crypto_larval *test;
376 	struct crypto_alg *alg;
377 	struct crypto_alg *q;
378 	LIST_HEAD(list);
379 	bool best;
380 
381 	down_write(&crypto_alg_sem);
382 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
383 		if (crypto_is_moribund(q) || !crypto_is_larval(q))
384 			continue;
385 
386 		test = (struct crypto_larval *)q;
387 
388 		if (!strcmp(q->cra_driver_name, name))
389 			goto found;
390 	}
391 
392 	pr_err("alg: Unexpected test result for %s: %d\n", name, err);
393 	goto unlock;
394 
395 found:
396 	q->cra_flags |= CRYPTO_ALG_DEAD;
397 	alg = test->adult;
398 
399 	if (crypto_is_dead(alg))
400 		goto complete;
401 
402 	if (err == -ECANCELED)
403 		alg->cra_flags |= CRYPTO_ALG_FIPS_INTERNAL;
404 	else if (err)
405 		goto complete;
406 	else
407 		alg->cra_flags &= ~CRYPTO_ALG_FIPS_INTERNAL;
408 
409 	alg->cra_flags |= CRYPTO_ALG_TESTED;
410 
411 	/*
412 	 * If a higher-priority implementation of the same algorithm is
413 	 * currently being tested, then don't fulfill request larvals.
414 	 */
415 	best = true;
416 	list_for_each_entry(q, &crypto_alg_list, cra_list) {
417 		if (crypto_is_moribund(q) || !crypto_is_larval(q))
418 			continue;
419 
420 		if (strcmp(alg->cra_name, q->cra_name))
421 			continue;
422 
423 		if (q->cra_priority > alg->cra_priority) {
424 			best = false;
425 			break;
426 		}
427 	}
428 
429 	crypto_alg_finish_registration(alg, best, &list);
430 
431 complete:
432 	complete_all(&test->completion);
433 
434 unlock:
435 	up_write(&crypto_alg_sem);
436 
437 	crypto_remove_final(&list);
438 }
439 EXPORT_SYMBOL_GPL(crypto_alg_tested);
440 
crypto_remove_final(struct list_head * list)441 void crypto_remove_final(struct list_head *list)
442 {
443 	struct crypto_alg *alg;
444 	struct crypto_alg *n;
445 
446 	list_for_each_entry_safe(alg, n, list, cra_list) {
447 		list_del_init(&alg->cra_list);
448 		crypto_alg_put(alg);
449 	}
450 }
451 EXPORT_SYMBOL_GPL(crypto_remove_final);
452 
crypto_register_alg(struct crypto_alg * alg)453 int crypto_register_alg(struct crypto_alg *alg)
454 {
455 	struct crypto_larval *larval;
456 	LIST_HEAD(algs_to_put);
457 	bool test_started = false;
458 	int err;
459 
460 	alg->cra_flags &= ~CRYPTO_ALG_DEAD;
461 	err = crypto_check_alg(alg);
462 	if (err)
463 		return err;
464 
465 	down_write(&crypto_alg_sem);
466 	larval = __crypto_register_alg(alg, &algs_to_put);
467 	if (!IS_ERR_OR_NULL(larval)) {
468 		test_started = crypto_boot_test_finished();
469 		larval->test_started = test_started;
470 	}
471 	up_write(&crypto_alg_sem);
472 
473 	if (IS_ERR(larval))
474 		return PTR_ERR(larval);
475 	if (test_started)
476 		crypto_wait_for_test(larval);
477 	crypto_remove_final(&algs_to_put);
478 	return 0;
479 }
480 EXPORT_SYMBOL_GPL(crypto_register_alg);
481 
crypto_remove_alg(struct crypto_alg * alg,struct list_head * list)482 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
483 {
484 	if (unlikely(list_empty(&alg->cra_list)))
485 		return -ENOENT;
486 
487 	alg->cra_flags |= CRYPTO_ALG_DEAD;
488 
489 	list_del_init(&alg->cra_list);
490 	crypto_remove_spawns(alg, list, NULL);
491 
492 	return 0;
493 }
494 
crypto_unregister_alg(struct crypto_alg * alg)495 void crypto_unregister_alg(struct crypto_alg *alg)
496 {
497 	int ret;
498 	LIST_HEAD(list);
499 
500 	down_write(&crypto_alg_sem);
501 	ret = crypto_remove_alg(alg, &list);
502 	up_write(&crypto_alg_sem);
503 
504 	if (WARN(ret, "Algorithm %s is not registered", alg->cra_driver_name))
505 		return;
506 
507 	if (WARN_ON(refcount_read(&alg->cra_refcnt) != 1))
508 		return;
509 
510 	if (alg->cra_destroy)
511 		alg->cra_destroy(alg);
512 
513 	crypto_remove_final(&list);
514 }
515 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
516 
crypto_register_algs(struct crypto_alg * algs,int count)517 int crypto_register_algs(struct crypto_alg *algs, int count)
518 {
519 	int i, ret;
520 
521 	for (i = 0; i < count; i++) {
522 		ret = crypto_register_alg(&algs[i]);
523 		if (ret)
524 			goto err;
525 	}
526 
527 	return 0;
528 
529 err:
530 	for (--i; i >= 0; --i)
531 		crypto_unregister_alg(&algs[i]);
532 
533 	return ret;
534 }
535 EXPORT_SYMBOL_GPL(crypto_register_algs);
536 
crypto_unregister_algs(struct crypto_alg * algs,int count)537 void crypto_unregister_algs(struct crypto_alg *algs, int count)
538 {
539 	int i;
540 
541 	for (i = 0; i < count; i++)
542 		crypto_unregister_alg(&algs[i]);
543 }
544 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
545 
crypto_register_template(struct crypto_template * tmpl)546 int crypto_register_template(struct crypto_template *tmpl)
547 {
548 	struct crypto_template *q;
549 	int err = -EEXIST;
550 
551 	down_write(&crypto_alg_sem);
552 
553 	crypto_check_module_sig(tmpl->module);
554 
555 	list_for_each_entry(q, &crypto_template_list, list) {
556 		if (q == tmpl)
557 			goto out;
558 	}
559 
560 	list_add(&tmpl->list, &crypto_template_list);
561 	err = 0;
562 out:
563 	up_write(&crypto_alg_sem);
564 	return err;
565 }
566 EXPORT_SYMBOL_GPL(crypto_register_template);
567 
crypto_register_templates(struct crypto_template * tmpls,int count)568 int crypto_register_templates(struct crypto_template *tmpls, int count)
569 {
570 	int i, err;
571 
572 	for (i = 0; i < count; i++) {
573 		err = crypto_register_template(&tmpls[i]);
574 		if (err)
575 			goto out;
576 	}
577 	return 0;
578 
579 out:
580 	for (--i; i >= 0; --i)
581 		crypto_unregister_template(&tmpls[i]);
582 	return err;
583 }
584 EXPORT_SYMBOL_GPL(crypto_register_templates);
585 
crypto_unregister_template(struct crypto_template * tmpl)586 void crypto_unregister_template(struct crypto_template *tmpl)
587 {
588 	struct crypto_instance *inst;
589 	struct hlist_node *n;
590 	struct hlist_head *list;
591 	LIST_HEAD(users);
592 
593 	down_write(&crypto_alg_sem);
594 
595 	BUG_ON(list_empty(&tmpl->list));
596 	list_del_init(&tmpl->list);
597 
598 	list = &tmpl->instances;
599 	hlist_for_each_entry(inst, list, list) {
600 		int err = crypto_remove_alg(&inst->alg, &users);
601 
602 		BUG_ON(err);
603 	}
604 
605 	up_write(&crypto_alg_sem);
606 
607 	hlist_for_each_entry_safe(inst, n, list, list) {
608 		BUG_ON(refcount_read(&inst->alg.cra_refcnt) != 1);
609 		crypto_free_instance(inst);
610 	}
611 	crypto_remove_final(&users);
612 }
613 EXPORT_SYMBOL_GPL(crypto_unregister_template);
614 
crypto_unregister_templates(struct crypto_template * tmpls,int count)615 void crypto_unregister_templates(struct crypto_template *tmpls, int count)
616 {
617 	int i;
618 
619 	for (i = count - 1; i >= 0; --i)
620 		crypto_unregister_template(&tmpls[i]);
621 }
622 EXPORT_SYMBOL_GPL(crypto_unregister_templates);
623 
__crypto_lookup_template(const char * name)624 static struct crypto_template *__crypto_lookup_template(const char *name)
625 {
626 	struct crypto_template *q, *tmpl = NULL;
627 
628 	down_read(&crypto_alg_sem);
629 	list_for_each_entry(q, &crypto_template_list, list) {
630 		if (strcmp(q->name, name))
631 			continue;
632 		if (unlikely(!crypto_tmpl_get(q)))
633 			continue;
634 
635 		tmpl = q;
636 		break;
637 	}
638 	up_read(&crypto_alg_sem);
639 
640 	return tmpl;
641 }
642 
crypto_lookup_template(const char * name)643 struct crypto_template *crypto_lookup_template(const char *name)
644 {
645 	return try_then_request_module(__crypto_lookup_template(name),
646 				       "crypto-%s", name);
647 }
648 EXPORT_SYMBOL_GPL(crypto_lookup_template);
649 
crypto_register_instance(struct crypto_template * tmpl,struct crypto_instance * inst)650 int crypto_register_instance(struct crypto_template *tmpl,
651 			     struct crypto_instance *inst)
652 {
653 	struct crypto_larval *larval;
654 	struct crypto_spawn *spawn;
655 	u32 fips_internal = 0;
656 	LIST_HEAD(algs_to_put);
657 	int err;
658 
659 	err = crypto_check_alg(&inst->alg);
660 	if (err)
661 		return err;
662 
663 	inst->alg.cra_module = tmpl->module;
664 	inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
665 
666 	down_write(&crypto_alg_sem);
667 
668 	larval = ERR_PTR(-EAGAIN);
669 	for (spawn = inst->spawns; spawn;) {
670 		struct crypto_spawn *next;
671 
672 		if (spawn->dead)
673 			goto unlock;
674 
675 		next = spawn->next;
676 		spawn->inst = inst;
677 		spawn->registered = true;
678 
679 		fips_internal |= spawn->alg->cra_flags;
680 
681 		crypto_mod_put(spawn->alg);
682 
683 		spawn = next;
684 	}
685 
686 	inst->alg.cra_flags |= (fips_internal & CRYPTO_ALG_FIPS_INTERNAL);
687 
688 	larval = __crypto_register_alg(&inst->alg, &algs_to_put);
689 	if (IS_ERR(larval))
690 		goto unlock;
691 	else if (larval)
692 		larval->test_started = true;
693 
694 	hlist_add_head(&inst->list, &tmpl->instances);
695 	inst->tmpl = tmpl;
696 
697 unlock:
698 	up_write(&crypto_alg_sem);
699 
700 	if (IS_ERR(larval))
701 		return PTR_ERR(larval);
702 	if (larval)
703 		crypto_wait_for_test(larval);
704 	crypto_remove_final(&algs_to_put);
705 	return 0;
706 }
707 EXPORT_SYMBOL_GPL(crypto_register_instance);
708 
crypto_unregister_instance(struct crypto_instance * inst)709 void crypto_unregister_instance(struct crypto_instance *inst)
710 {
711 	LIST_HEAD(list);
712 
713 	down_write(&crypto_alg_sem);
714 
715 	crypto_remove_spawns(&inst->alg, &list, NULL);
716 	crypto_remove_instance(inst, &list);
717 
718 	up_write(&crypto_alg_sem);
719 
720 	crypto_remove_final(&list);
721 }
722 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
723 
crypto_grab_spawn(struct crypto_spawn * spawn,struct crypto_instance * inst,const char * name,u32 type,u32 mask)724 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
725 		      const char *name, u32 type, u32 mask)
726 {
727 	struct crypto_alg *alg;
728 	int err = -EAGAIN;
729 
730 	if (WARN_ON_ONCE(inst == NULL))
731 		return -EINVAL;
732 
733 	/* Allow the result of crypto_attr_alg_name() to be passed directly */
734 	if (IS_ERR(name))
735 		return PTR_ERR(name);
736 
737 	alg = crypto_find_alg(name, spawn->frontend,
738 			      type | CRYPTO_ALG_FIPS_INTERNAL, mask);
739 	if (IS_ERR(alg))
740 		return PTR_ERR(alg);
741 
742 	down_write(&crypto_alg_sem);
743 	if (!crypto_is_moribund(alg)) {
744 		list_add(&spawn->list, &alg->cra_users);
745 		spawn->alg = alg;
746 		spawn->mask = mask;
747 		spawn->next = inst->spawns;
748 		inst->spawns = spawn;
749 		inst->alg.cra_flags |=
750 			(alg->cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
751 		err = 0;
752 	}
753 	up_write(&crypto_alg_sem);
754 	if (err)
755 		crypto_mod_put(alg);
756 	return err;
757 }
758 EXPORT_SYMBOL_GPL(crypto_grab_spawn);
759 
crypto_drop_spawn(struct crypto_spawn * spawn)760 void crypto_drop_spawn(struct crypto_spawn *spawn)
761 {
762 	if (!spawn->alg) /* not yet initialized? */
763 		return;
764 
765 	down_write(&crypto_alg_sem);
766 	if (!spawn->dead)
767 		list_del(&spawn->list);
768 	up_write(&crypto_alg_sem);
769 
770 	if (!spawn->registered)
771 		crypto_mod_put(spawn->alg);
772 }
773 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
774 
crypto_spawn_alg(struct crypto_spawn * spawn)775 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
776 {
777 	struct crypto_alg *alg = ERR_PTR(-EAGAIN);
778 	struct crypto_alg *target;
779 	bool shoot = false;
780 
781 	down_read(&crypto_alg_sem);
782 	if (!spawn->dead) {
783 		alg = spawn->alg;
784 		if (!crypto_mod_get(alg)) {
785 			target = crypto_alg_get(alg);
786 			shoot = true;
787 			alg = ERR_PTR(-EAGAIN);
788 		}
789 	}
790 	up_read(&crypto_alg_sem);
791 
792 	if (shoot) {
793 		crypto_shoot_alg(target);
794 		crypto_alg_put(target);
795 	}
796 
797 	return alg;
798 }
799 
crypto_spawn_tfm(struct crypto_spawn * spawn,u32 type,u32 mask)800 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
801 				    u32 mask)
802 {
803 	struct crypto_alg *alg;
804 	struct crypto_tfm *tfm;
805 
806 	alg = crypto_spawn_alg(spawn);
807 	if (IS_ERR(alg))
808 		return ERR_CAST(alg);
809 
810 	tfm = ERR_PTR(-EINVAL);
811 	if (unlikely((alg->cra_flags ^ type) & mask))
812 		goto out_put_alg;
813 
814 	tfm = __crypto_alloc_tfm(alg, type, mask);
815 	if (IS_ERR(tfm))
816 		goto out_put_alg;
817 
818 	return tfm;
819 
820 out_put_alg:
821 	crypto_mod_put(alg);
822 	return tfm;
823 }
824 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
825 
crypto_spawn_tfm2(struct crypto_spawn * spawn)826 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
827 {
828 	struct crypto_alg *alg;
829 	struct crypto_tfm *tfm;
830 
831 	alg = crypto_spawn_alg(spawn);
832 	if (IS_ERR(alg))
833 		return ERR_CAST(alg);
834 
835 	tfm = crypto_create_tfm(alg, spawn->frontend);
836 	if (IS_ERR(tfm))
837 		goto out_put_alg;
838 
839 	return tfm;
840 
841 out_put_alg:
842 	crypto_mod_put(alg);
843 	return tfm;
844 }
845 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
846 
crypto_register_notifier(struct notifier_block * nb)847 int crypto_register_notifier(struct notifier_block *nb)
848 {
849 	return blocking_notifier_chain_register(&crypto_chain, nb);
850 }
851 EXPORT_SYMBOL_GPL(crypto_register_notifier);
852 
crypto_unregister_notifier(struct notifier_block * nb)853 int crypto_unregister_notifier(struct notifier_block *nb)
854 {
855 	return blocking_notifier_chain_unregister(&crypto_chain, nb);
856 }
857 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
858 
crypto_get_attr_type(struct rtattr ** tb)859 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
860 {
861 	struct rtattr *rta = tb[0];
862 	struct crypto_attr_type *algt;
863 
864 	if (!rta)
865 		return ERR_PTR(-ENOENT);
866 	if (RTA_PAYLOAD(rta) < sizeof(*algt))
867 		return ERR_PTR(-EINVAL);
868 	if (rta->rta_type != CRYPTOA_TYPE)
869 		return ERR_PTR(-EINVAL);
870 
871 	algt = RTA_DATA(rta);
872 
873 	return algt;
874 }
875 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
876 
877 /**
878  * crypto_check_attr_type() - check algorithm type and compute inherited mask
879  * @tb: the template parameters
880  * @type: the algorithm type the template would be instantiated as
881  * @mask_ret: (output) the mask that should be passed to crypto_grab_*()
882  *	      to restrict the flags of any inner algorithms
883  *
884  * Validate that the algorithm type the user requested is compatible with the
885  * one the template would actually be instantiated as.  E.g., if the user is
886  * doing crypto_alloc_shash("cbc(aes)", ...), this would return an error because
887  * the "cbc" template creates an "skcipher" algorithm, not an "shash" algorithm.
888  *
889  * Also compute the mask to use to restrict the flags of any inner algorithms.
890  *
891  * Return: 0 on success; -errno on failure
892  */
crypto_check_attr_type(struct rtattr ** tb,u32 type,u32 * mask_ret)893 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret)
894 {
895 	struct crypto_attr_type *algt;
896 
897 	algt = crypto_get_attr_type(tb);
898 	if (IS_ERR(algt))
899 		return PTR_ERR(algt);
900 
901 	if ((algt->type ^ type) & algt->mask)
902 		return -EINVAL;
903 
904 	*mask_ret = crypto_algt_inherited_mask(algt);
905 	return 0;
906 }
907 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
908 
crypto_attr_alg_name(struct rtattr * rta)909 const char *crypto_attr_alg_name(struct rtattr *rta)
910 {
911 	struct crypto_attr_alg *alga;
912 
913 	if (!rta)
914 		return ERR_PTR(-ENOENT);
915 	if (RTA_PAYLOAD(rta) < sizeof(*alga))
916 		return ERR_PTR(-EINVAL);
917 	if (rta->rta_type != CRYPTOA_ALG)
918 		return ERR_PTR(-EINVAL);
919 
920 	alga = RTA_DATA(rta);
921 	alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
922 
923 	return alga->name;
924 }
925 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
926 
crypto_inst_setname(struct crypto_instance * inst,const char * name,struct crypto_alg * alg)927 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
928 			struct crypto_alg *alg)
929 {
930 	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
931 		     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
932 		return -ENAMETOOLONG;
933 
934 	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
935 		     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
936 		return -ENAMETOOLONG;
937 
938 	return 0;
939 }
940 EXPORT_SYMBOL_GPL(crypto_inst_setname);
941 
crypto_init_queue(struct crypto_queue * queue,unsigned int max_qlen)942 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
943 {
944 	INIT_LIST_HEAD(&queue->list);
945 	queue->backlog = &queue->list;
946 	queue->qlen = 0;
947 	queue->max_qlen = max_qlen;
948 }
949 EXPORT_SYMBOL_GPL(crypto_init_queue);
950 
crypto_enqueue_request(struct crypto_queue * queue,struct crypto_async_request * request)951 int crypto_enqueue_request(struct crypto_queue *queue,
952 			   struct crypto_async_request *request)
953 {
954 	int err = -EINPROGRESS;
955 
956 	if (unlikely(queue->qlen >= queue->max_qlen)) {
957 		if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
958 			err = -ENOSPC;
959 			goto out;
960 		}
961 		err = -EBUSY;
962 		if (queue->backlog == &queue->list)
963 			queue->backlog = &request->list;
964 	}
965 
966 	queue->qlen++;
967 	list_add_tail(&request->list, &queue->list);
968 
969 out:
970 	return err;
971 }
972 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
973 
crypto_enqueue_request_head(struct crypto_queue * queue,struct crypto_async_request * request)974 void crypto_enqueue_request_head(struct crypto_queue *queue,
975 				 struct crypto_async_request *request)
976 {
977 	if (unlikely(queue->qlen >= queue->max_qlen))
978 		queue->backlog = queue->backlog->prev;
979 
980 	queue->qlen++;
981 	list_add(&request->list, &queue->list);
982 }
983 EXPORT_SYMBOL_GPL(crypto_enqueue_request_head);
984 
crypto_dequeue_request(struct crypto_queue * queue)985 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
986 {
987 	struct list_head *request;
988 
989 	if (unlikely(!queue->qlen))
990 		return NULL;
991 
992 	queue->qlen--;
993 
994 	if (queue->backlog != &queue->list)
995 		queue->backlog = queue->backlog->next;
996 
997 	request = queue->list.next;
998 	list_del(request);
999 
1000 	return list_entry(request, struct crypto_async_request, list);
1001 }
1002 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
1003 
crypto_inc_byte(u8 * a,unsigned int size)1004 static inline void crypto_inc_byte(u8 *a, unsigned int size)
1005 {
1006 	u8 *b = (a + size);
1007 	u8 c;
1008 
1009 	for (; size; size--) {
1010 		c = *--b + 1;
1011 		*b = c;
1012 		if (c)
1013 			break;
1014 	}
1015 }
1016 
crypto_inc(u8 * a,unsigned int size)1017 void crypto_inc(u8 *a, unsigned int size)
1018 {
1019 	__be32 *b = (__be32 *)(a + size);
1020 	u32 c;
1021 
1022 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
1023 	    IS_ALIGNED((unsigned long)b, __alignof__(*b)))
1024 		for (; size >= 4; size -= 4) {
1025 			c = be32_to_cpu(*--b) + 1;
1026 			*b = cpu_to_be32(c);
1027 			if (likely(c))
1028 				return;
1029 		}
1030 
1031 	crypto_inc_byte(a, size);
1032 }
1033 EXPORT_SYMBOL_GPL(crypto_inc);
1034 
crypto_alg_extsize(struct crypto_alg * alg)1035 unsigned int crypto_alg_extsize(struct crypto_alg *alg)
1036 {
1037 	return alg->cra_ctxsize +
1038 	       (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
1039 }
1040 EXPORT_SYMBOL_GPL(crypto_alg_extsize);
1041 
crypto_type_has_alg(const char * name,const struct crypto_type * frontend,u32 type,u32 mask)1042 int crypto_type_has_alg(const char *name, const struct crypto_type *frontend,
1043 			u32 type, u32 mask)
1044 {
1045 	int ret = 0;
1046 	struct crypto_alg *alg = crypto_find_alg(name, frontend, type, mask);
1047 
1048 	if (!IS_ERR(alg)) {
1049 		crypto_mod_put(alg);
1050 		ret = 1;
1051 	}
1052 
1053 	return ret;
1054 }
1055 EXPORT_SYMBOL_GPL(crypto_type_has_alg);
1056 
crypto_start_tests(void)1057 static void __init crypto_start_tests(void)
1058 {
1059 	if (IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS))
1060 		return;
1061 
1062 	for (;;) {
1063 		struct crypto_larval *larval = NULL;
1064 		struct crypto_alg *q;
1065 
1066 		down_write(&crypto_alg_sem);
1067 
1068 		list_for_each_entry(q, &crypto_alg_list, cra_list) {
1069 			struct crypto_larval *l;
1070 
1071 			if (!crypto_is_larval(q))
1072 				continue;
1073 
1074 			l = (void *)q;
1075 
1076 			if (!crypto_is_test_larval(l))
1077 				continue;
1078 
1079 			if (l->test_started)
1080 				continue;
1081 
1082 			l->test_started = true;
1083 			larval = l;
1084 			break;
1085 		}
1086 
1087 		up_write(&crypto_alg_sem);
1088 
1089 		if (!larval)
1090 			break;
1091 
1092 		crypto_wait_for_test(larval);
1093 	}
1094 
1095 	set_crypto_boot_test_finished();
1096 }
1097 
crypto_algapi_init(void)1098 static int __init crypto_algapi_init(void)
1099 {
1100 	crypto_init_proc();
1101 	crypto_start_tests();
1102 	return 0;
1103 }
1104 
crypto_algapi_exit(void)1105 static void __exit crypto_algapi_exit(void)
1106 {
1107 	crypto_exit_proc();
1108 }
1109 
1110 /*
1111  * We run this at late_initcall so that all the built-in algorithms
1112  * have had a chance to register themselves first.
1113  */
1114 late_initcall(crypto_algapi_init);
1115 module_exit(crypto_algapi_exit);
1116 
1117 MODULE_LICENSE("GPL");
1118 MODULE_DESCRIPTION("Cryptographic algorithms API");
1119 MODULE_SOFTDEP("pre: cryptomgr");
1120