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
  24static LIST_HEAD(crypto_template_list);
  25
  26#ifdef CONFIG_CRYPTO_MANAGER_EXTRA_TESTS
  27DEFINE_PER_CPU(bool, crypto_simd_disabled_for_test);
  28EXPORT_PER_CPU_SYMBOL_GPL(crypto_simd_disabled_for_test);
  29#endif
  30
  31static 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
  38static 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
  73static void crypto_free_instance(struct crypto_instance *inst)
  74{
  75	inst->alg.cra_type->free(inst);
  76}
  77
  78static 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
  88static 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 */
 107static 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
 131static 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 */
 157void 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}
 235EXPORT_SYMBOL_GPL(crypto_remove_spawns);
 236
 237static 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
 288static 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
 316static struct crypto_larval *
 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
 365out:
 366	return larval;
 367
 368err:
 369	larval = ERR_PTR(ret);
 370	goto out;
 371}
 372
 373void 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
 395found:
 396	q->cra_flags |= CRYPTO_ALG_DEAD;
 397	alg = test->adult;
 398
 399	if (list_empty(&alg->cra_list))
 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
 431complete:
 432	complete_all(&test->completion);
 433
 434unlock:
 435	up_write(&crypto_alg_sem);
 436
 437	crypto_remove_final(&list);
 438}
 439EXPORT_SYMBOL_GPL(crypto_alg_tested);
 440
 441void 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}
 451EXPORT_SYMBOL_GPL(crypto_remove_final);
 452
 453int 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}
 480EXPORT_SYMBOL_GPL(crypto_register_alg);
 481
 482static 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
 495void 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}
 515EXPORT_SYMBOL_GPL(crypto_unregister_alg);
 516
 517int 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
 529err:
 530	for (--i; i >= 0; --i)
 531		crypto_unregister_alg(&algs[i]);
 532
 533	return ret;
 534}
 535EXPORT_SYMBOL_GPL(crypto_register_algs);
 536
 537void 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}
 544EXPORT_SYMBOL_GPL(crypto_unregister_algs);
 545
 546int 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;
 562out:
 563	up_write(&crypto_alg_sem);
 564	return err;
 565}
 566EXPORT_SYMBOL_GPL(crypto_register_template);
 567
 568int 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
 579out:
 580	for (--i; i >= 0; --i)
 581		crypto_unregister_template(&tmpls[i]);
 582	return err;
 583}
 584EXPORT_SYMBOL_GPL(crypto_register_templates);
 585
 586void 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}
 613EXPORT_SYMBOL_GPL(crypto_unregister_template);
 614
 615void 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}
 622EXPORT_SYMBOL_GPL(crypto_unregister_templates);
 623
 624static 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
 643struct crypto_template *crypto_lookup_template(const char *name)
 644{
 645	return try_then_request_module(__crypto_lookup_template(name),
 646				       "crypto-%s", name);
 647}
 648EXPORT_SYMBOL_GPL(crypto_lookup_template);
 649
 650int 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
 697unlock:
 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}
 707EXPORT_SYMBOL_GPL(crypto_register_instance);
 708
 709void 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}
 722EXPORT_SYMBOL_GPL(crypto_unregister_instance);
 723
 724int 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}
 758EXPORT_SYMBOL_GPL(crypto_grab_spawn);
 759
 760void 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}
 773EXPORT_SYMBOL_GPL(crypto_drop_spawn);
 774
 775static 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
 800struct 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
 820out_put_alg:
 821	crypto_mod_put(alg);
 822	return tfm;
 823}
 824EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
 825
 826void *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
 841out_put_alg:
 842	crypto_mod_put(alg);
 843	return tfm;
 844}
 845EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
 846
 847int crypto_register_notifier(struct notifier_block *nb)
 848{
 849	return blocking_notifier_chain_register(&crypto_chain, nb);
 850}
 851EXPORT_SYMBOL_GPL(crypto_register_notifier);
 852
 853int crypto_unregister_notifier(struct notifier_block *nb)
 854{
 855	return blocking_notifier_chain_unregister(&crypto_chain, nb);
 856}
 857EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
 858
 859struct 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}
 875EXPORT_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 */
 893int 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}
 907EXPORT_SYMBOL_GPL(crypto_check_attr_type);
 908
 909const 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}
 925EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
 926
 927int 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}
 940EXPORT_SYMBOL_GPL(crypto_inst_setname);
 941
 942void 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}
 949EXPORT_SYMBOL_GPL(crypto_init_queue);
 950
 951int 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
 969out:
 970	return err;
 971}
 972EXPORT_SYMBOL_GPL(crypto_enqueue_request);
 973
 974void 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}
 983EXPORT_SYMBOL_GPL(crypto_enqueue_request_head);
 984
 985struct 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}
1002EXPORT_SYMBOL_GPL(crypto_dequeue_request);
1003
1004static 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
1017void 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}
1033EXPORT_SYMBOL_GPL(crypto_inc);
1034
1035unsigned int crypto_alg_extsize(struct crypto_alg *alg)
1036{
1037	return alg->cra_ctxsize +
1038	       (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
1039}
1040EXPORT_SYMBOL_GPL(crypto_alg_extsize);
1041
1042int 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}
1055EXPORT_SYMBOL_GPL(crypto_type_has_alg);
1056
1057static 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
1098static int __init crypto_algapi_init(void)
1099{
1100	crypto_init_proc();
1101	crypto_start_tests();
1102	return 0;
1103}
1104
1105static 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 */
1114late_initcall(crypto_algapi_init);
1115module_exit(crypto_algapi_exit);
1116
1117MODULE_LICENSE("GPL");
1118MODULE_DESCRIPTION("Cryptographic algorithms API");
1119MODULE_SOFTDEP("pre: cryptomgr");