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