crypto/algapi.c

   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
  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
  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
  73 static void crypto_free_instance(struct crypto_instance *inst)
  74 {
  75         inst->alg.cra_type->free(inst);
  76 }
  77
  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
  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  */
 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
 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  */
 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
 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
 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 *
 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_name, alg->cra_driver_name))
 345                         goto err;
 346         }
 347
 348         larval = crypto_alloc_test_larval(alg);
 349         if (IS_ERR(larval))
 350                 goto out;
 351
 352         list_add(&alg->cra_list, &crypto_alg_list);
 353
 354         if (larval) {
 355                 /* No cheating! */
 356                 alg->cra_flags &= ~CRYPTO_ALG_TESTED;
 357
 358                 list_add(&larval->alg.cra_list, &crypto_alg_list);
 359         } else {
 360                 alg->cra_flags |= CRYPTO_ALG_TESTED;
 361                 crypto_alg_finish_registration(alg, true, algs_to_put);
 362         }
 363
 364 out:
 365         return larval;
 366
 367 err:
 368         larval = ERR_PTR(ret);
 369         goto out;
 370 }
 371
 372 void crypto_alg_tested(const char *name, int err)
 373 {
 374         struct crypto_larval *test;
 375         struct crypto_alg *alg;
 376         struct crypto_alg *q;
 377         LIST_HEAD(list);
 378         bool best;
 379
 380         down_write(&crypto_alg_sem);
 381         list_for_each_entry(q, &crypto_alg_list, cra_list) {
 382                 if (crypto_is_moribund(q) || !crypto_is_larval(q))
 383                         continue;
 384
 385                 test = (struct crypto_larval *)q;
 386
 387                 if (!strcmp(q->cra_driver_name, name))
 388                         goto found;
 389         }
 390
 391         pr_err("alg: Unexpected test result for %s: %d\n", name, err);
 392         goto unlock;
 393
 394 found:
 395         q->cra_flags |= CRYPTO_ALG_DEAD;
 396         alg = test->adult;
 397
 398         if (list_empty(&alg->cra_list))
 399                 goto complete;
 400
 401         if (err == -ECANCELED)
 402                 alg->cra_flags |= CRYPTO_ALG_FIPS_INTERNAL;
 403         else if (err)
 404                 goto complete;
 405         else
 406                 alg->cra_flags &= ~CRYPTO_ALG_FIPS_INTERNAL;
 407
 408         alg->cra_flags |= CRYPTO_ALG_TESTED;
 409
 410         /*
 411          * If a higher-priority implementation of the same algorithm is
 412          * currently being tested, then don't fulfill request larvals.
 413          */
 414         best = true;
 415         list_for_each_entry(q, &crypto_alg_list, cra_list) {
 416                 if (crypto_is_moribund(q) || !crypto_is_larval(q))
 417                         continue;
 418
 419                 if (strcmp(alg->cra_name, q->cra_name))
 420                         continue;
 421
 422                 if (q->cra_priority > alg->cra_priority) {
 423                         best = false;
 424                         break;
 425                 }
 426         }
 427
 428         crypto_alg_finish_registration(alg, best, &list);
 429
 430 complete:
 431         complete_all(&test->completion);
 432
 433 unlock:
 434         up_write(&crypto_alg_sem);
 435
 436         crypto_remove_final(&list);
 437 }
 438 EXPORT_SYMBOL_GPL(crypto_alg_tested);
 439
 440 void crypto_remove_final(struct list_head *list)
 441 {
 442         struct crypto_alg *alg;
 443         struct crypto_alg *n;
 444
 445         list_for_each_entry_safe(alg, n, list, cra_list) {
 446                 list_del_init(&alg->cra_list);
 447                 crypto_alg_put(alg);
 448         }
 449 }
 450 EXPORT_SYMBOL_GPL(crypto_remove_final);
 451
 452 int crypto_register_alg(struct crypto_alg *alg)
 453 {
 454         struct crypto_larval *larval;
 455         LIST_HEAD(algs_to_put);
 456         bool test_started = false;
 457         int err;
 458
 459         alg->cra_flags &= ~CRYPTO_ALG_DEAD;
 460         err = crypto_check_alg(alg);
 461         if (err)
 462                 return err;
 463
 464         down_write(&crypto_alg_sem);
 465         larval = __crypto_register_alg(alg, &algs_to_put);
 466         if (!IS_ERR_OR_NULL(larval)) {
 467                 test_started = crypto_boot_test_finished();
 468                 larval->test_started = test_started;
 469         }
 470         up_write(&crypto_alg_sem);
 471
 472         if (IS_ERR(larval))
 473                 return PTR_ERR(larval);
 474         if (test_started)
 475                 crypto_wait_for_test(larval);
 476         crypto_remove_final(&algs_to_put);
 477         return 0;
 478 }
 479 EXPORT_SYMBOL_GPL(crypto_register_alg);
 480
 481 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
 482 {
 483         if (unlikely(list_empty(&alg->cra_list)))
 484                 return -ENOENT;
 485
 486         alg->cra_flags |= CRYPTO_ALG_DEAD;
 487
 488         list_del_init(&alg->cra_list);
 489         crypto_remove_spawns(alg, list, NULL);
 490
 491         return 0;
 492 }
 493
 494 void crypto_unregister_alg(struct crypto_alg *alg)
 495 {
 496         int ret;
 497         LIST_HEAD(list);
 498
 499         down_write(&crypto_alg_sem);
 500         ret = crypto_remove_alg(alg, &list);
 501         up_write(&crypto_alg_sem);
 502
 503         if (WARN(ret, "Algorithm %s is not registered", alg->cra_driver_name))
 504                 return;
 505
 506         if (WARN_ON(refcount_read(&alg->cra_refcnt) != 1))
 507                 return;
 508
 509         if (alg->cra_destroy)
 510                 alg->cra_destroy(alg);
 511
 512         crypto_remove_final(&list);
 513 }
 514 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
 515
 516 int crypto_register_algs(struct crypto_alg *algs, int count)
 517 {
 518         int i, ret;
 519
 520         for (i = 0; i < count; i++) {
 521                 ret = crypto_register_alg(&algs[i]);
 522                 if (ret)
 523                         goto err;
 524         }
 525
 526         return 0;
 527
 528 err:
 529         for (--i; i >= 0; --i)
 530                 crypto_unregister_alg(&algs[i]);
 531
 532         return ret;
 533 }
 534 EXPORT_SYMBOL_GPL(crypto_register_algs);
 535
 536 void crypto_unregister_algs(struct crypto_alg *algs, int count)
 537 {
 538         int i;
 539
 540         for (i = 0; i < count; i++)
 541                 crypto_unregister_alg(&algs[i]);
 542 }
 543 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
 544
 545 int crypto_register_template(struct crypto_template *tmpl)
 546 {
 547         struct crypto_template *q;
 548         int err = -EEXIST;
 549
 550         down_write(&crypto_alg_sem);
 551
 552         crypto_check_module_sig(tmpl->module);
 553
 554         list_for_each_entry(q, &crypto_template_list, list) {
 555                 if (q == tmpl)
 556                         goto out;
 557         }
 558
 559         list_add(&tmpl->list, &crypto_template_list);
 560         err = 0;
 561 out:
 562         up_write(&crypto_alg_sem);
 563         return err;
 564 }
 565 EXPORT_SYMBOL_GPL(crypto_register_template);
 566
 567 int crypto_register_templates(struct crypto_template *tmpls, int count)
 568 {
 569         int i, err;
 570
 571         for (i = 0; i < count; i++) {
 572                 err = crypto_register_template(&tmpls[i]);
 573                 if (err)
 574                         goto out;
 575         }
 576         return 0;
 577
 578 out:
 579         for (--i; i >= 0; --i)
 580                 crypto_unregister_template(&tmpls[i]);
 581         return err;
 582 }
 583 EXPORT_SYMBOL_GPL(crypto_register_templates);
 584
 585 void crypto_unregister_template(struct crypto_template *tmpl)
 586 {
 587         struct crypto_instance *inst;
 588         struct hlist_node *n;
 589         struct hlist_head *list;
 590         LIST_HEAD(users);
 591
 592         down_write(&crypto_alg_sem);
 593
 594         BUG_ON(list_empty(&tmpl->list));
 595         list_del_init(&tmpl->list);
 596
 597         list = &tmpl->instances;
 598         hlist_for_each_entry(inst, list, list) {
 599                 int err = crypto_remove_alg(&inst->alg, &users);
 600
 601                 BUG_ON(err);
 602         }
 603
 604         up_write(&crypto_alg_sem);
 605
 606         hlist_for_each_entry_safe(inst, n, list, list) {
 607                 BUG_ON(refcount_read(&inst->alg.cra_refcnt) != 1);
 608                 crypto_free_instance(inst);
 609         }
 610         crypto_remove_final(&users);
 611 }
 612 EXPORT_SYMBOL_GPL(crypto_unregister_template);
 613
 614 void crypto_unregister_templates(struct crypto_template *tmpls, int count)
 615 {
 616         int i;
 617
 618         for (i = count - 1; i >= 0; --i)
 619                 crypto_unregister_template(&tmpls[i]);
 620 }
 621 EXPORT_SYMBOL_GPL(crypto_unregister_templates);
 622
 623 static struct crypto_template *__crypto_lookup_template(const char *name)
 624 {
 625         struct crypto_template *q, *tmpl = NULL;
 626
 627         down_read(&crypto_alg_sem);
 628         list_for_each_entry(q, &crypto_template_list, list) {
 629                 if (strcmp(q->name, name))
 630                         continue;
 631                 if (unlikely(!crypto_tmpl_get(q)))
 632                         continue;
 633
 634                 tmpl = q;
 635                 break;
 636         }
 637         up_read(&crypto_alg_sem);
 638
 639         return tmpl;
 640 }
 641
 642 struct crypto_template *crypto_lookup_template(const char *name)
 643 {
 644         return try_then_request_module(__crypto_lookup_template(name),
 645                                        "crypto-%s", name);
 646 }
 647 EXPORT_SYMBOL_GPL(crypto_lookup_template);
 648
 649 int crypto_register_instance(struct crypto_template *tmpl,
 650                              struct crypto_instance *inst)
 651 {
 652         struct crypto_larval *larval;
 653         struct crypto_spawn *spawn;
 654         u32 fips_internal = 0;
 655         LIST_HEAD(algs_to_put);
 656         int err;
 657
 658         err = crypto_check_alg(&inst->alg);
 659         if (err)
 660                 return err;
 661
 662         inst->alg.cra_module = tmpl->module;
 663         inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
 664
 665         down_write(&crypto_alg_sem);
 666
 667         larval = ERR_PTR(-EAGAIN);
 668         for (spawn = inst->spawns; spawn;) {
 669                 struct crypto_spawn *next;
 670
 671                 if (spawn->dead)
 672                         goto unlock;
 673
 674                 next = spawn->next;
 675                 spawn->inst = inst;
 676                 spawn->registered = true;
 677
 678                 fips_internal |= spawn->alg->cra_flags;
 679
 680                 crypto_mod_put(spawn->alg);
 681
 682                 spawn = next;
 683         }
 684
 685         inst->alg.cra_flags |= (fips_internal & CRYPTO_ALG_FIPS_INTERNAL);
 686
 687         larval = __crypto_register_alg(&inst->alg, &algs_to_put);
 688         if (IS_ERR(larval))
 689                 goto unlock;
 690         else if (larval)
 691                 larval->test_started = true;
 692
 693         hlist_add_head(&inst->list, &tmpl->instances);
 694         inst->tmpl = tmpl;
 695
 696 unlock:
 697         up_write(&crypto_alg_sem);
 698
 699         if (IS_ERR(larval))
 700                 return PTR_ERR(larval);
 701         if (larval)
 702                 crypto_wait_for_test(larval);
 703         crypto_remove_final(&algs_to_put);
 704         return 0;
 705 }
 706 EXPORT_SYMBOL_GPL(crypto_register_instance);
 707
 708 void crypto_unregister_instance(struct crypto_instance *inst)
 709 {
 710         LIST_HEAD(list);
 711
 712         down_write(&crypto_alg_sem);
 713
 714         crypto_remove_spawns(&inst->alg, &list, NULL);
 715         crypto_remove_instance(inst, &list);
 716
 717         up_write(&crypto_alg_sem);
 718
 719         crypto_remove_final(&list);
 720 }
 721 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
 722
 723 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
 724                       const char *name, u32 type, u32 mask)
 725 {
 726         struct crypto_alg *alg;
 727         int err = -EAGAIN;
 728
 729         if (WARN_ON_ONCE(inst == NULL))
 730                 return -EINVAL;
 731
 732         /* Allow the result of crypto_attr_alg_name() to be passed directly */
 733         if (IS_ERR(name))
 734                 return PTR_ERR(name);
 735
 736         alg = crypto_find_alg(name, spawn->frontend,
 737                               type | CRYPTO_ALG_FIPS_INTERNAL, mask);
 738         if (IS_ERR(alg))
 739                 return PTR_ERR(alg);
 740
 741         down_write(&crypto_alg_sem);
 742         if (!crypto_is_moribund(alg)) {
 743                 list_add(&spawn->list, &alg->cra_users);
 744                 spawn->alg = alg;
 745                 spawn->mask = mask;
 746                 spawn->next = inst->spawns;
 747                 inst->spawns = spawn;
 748                 inst->alg.cra_flags |=
 749                         (alg->cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
 750                 err = 0;
 751         }
 752         up_write(&crypto_alg_sem);
 753         if (err)
 754                 crypto_mod_put(alg);
 755         return err;
 756 }
 757 EXPORT_SYMBOL_GPL(crypto_grab_spawn);
 758
 759 void crypto_drop_spawn(struct crypto_spawn *spawn)
 760 {
 761         if (!spawn->alg) /* not yet initialized? */
 762                 return;
 763
 764         down_write(&crypto_alg_sem);
 765         if (!spawn->dead)
 766                 list_del(&spawn->list);
 767         up_write(&crypto_alg_sem);
 768
 769         if (!spawn->registered)
 770                 crypto_mod_put(spawn->alg);
 771 }
 772 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
 773
 774 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
 775 {
 776         struct crypto_alg *alg = ERR_PTR(-EAGAIN);
 777         struct crypto_alg *target;
 778         bool shoot = false;
 779
 780         down_read(&crypto_alg_sem);
 781         if (!spawn->dead) {
 782                 alg = spawn->alg;
 783                 if (!crypto_mod_get(alg)) {
 784                         target = crypto_alg_get(alg);
 785                         shoot = true;
 786                         alg = ERR_PTR(-EAGAIN);
 787                 }
 788         }
 789         up_read(&crypto_alg_sem);
 790
 791         if (shoot) {
 792                 crypto_shoot_alg(target);
 793                 crypto_alg_put(target);
 794         }
 795
 796         return alg;
 797 }
 798
 799 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
 800                                     u32 mask)
 801 {
 802         struct crypto_alg *alg;
 803         struct crypto_tfm *tfm;
 804
 805         alg = crypto_spawn_alg(spawn);
 806         if (IS_ERR(alg))
 807                 return ERR_CAST(alg);
 808
 809         tfm = ERR_PTR(-EINVAL);
 810         if (unlikely((alg->cra_flags ^ type) & mask))
 811                 goto out_put_alg;
 812
 813         tfm = __crypto_alloc_tfm(alg, type, mask);
 814         if (IS_ERR(tfm))
 815                 goto out_put_alg;
 816
 817         return tfm;
 818
 819 out_put_alg:
 820         crypto_mod_put(alg);
 821         return tfm;
 822 }
 823 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
 824
 825 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
 826 {
 827         struct crypto_alg *alg;
 828         struct crypto_tfm *tfm;
 829
 830         alg = crypto_spawn_alg(spawn);
 831         if (IS_ERR(alg))
 832                 return ERR_CAST(alg);
 833
 834         tfm = crypto_create_tfm(alg, spawn->frontend);
 835         if (IS_ERR(tfm))
 836                 goto out_put_alg;
 837
 838         return tfm;
 839
 840 out_put_alg:
 841         crypto_mod_put(alg);
 842         return tfm;
 843 }
 844 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
 845
 846 int crypto_register_notifier(struct notifier_block *nb)
 847 {
 848         return blocking_notifier_chain_register(&crypto_chain, nb);
 849 }
 850 EXPORT_SYMBOL_GPL(crypto_register_notifier);
 851
 852 int crypto_unregister_notifier(struct notifier_block *nb)
 853 {
 854         return blocking_notifier_chain_unregister(&crypto_chain, nb);
 855 }
 856 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
 857
 858 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
 859 {
 860         struct rtattr *rta = tb[0];
 861         struct crypto_attr_type *algt;
 862
 863         if (!rta)
 864                 return ERR_PTR(-ENOENT);
 865         if (RTA_PAYLOAD(rta) < sizeof(*algt))
 866                 return ERR_PTR(-EINVAL);
 867         if (rta->rta_type != CRYPTOA_TYPE)
 868                 return ERR_PTR(-EINVAL);
 869
 870         algt = RTA_DATA(rta);
 871
 872         return algt;
 873 }
 874 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
 875
 876 /**
 877  * crypto_check_attr_type() - check algorithm type and compute inherited mask
 878  * @tb: the template parameters
 879  * @type: the algorithm type the template would be instantiated as
 880  * @mask_ret: (output) the mask that should be passed to crypto_grab_*()
 881  *            to restrict the flags of any inner algorithms
 882  *
 883  * Validate that the algorithm type the user requested is compatible with the
 884  * one the template would actually be instantiated as.  E.g., if the user is
 885  * doing crypto_alloc_shash("cbc(aes)", ...), this would return an error because
 886  * the "cbc" template creates an "skcipher" algorithm, not an "shash" algorithm.
 887  *
 888  * Also compute the mask to use to restrict the flags of any inner algorithms.
 889  *
 890  * Return: 0 on success; -errno on failure
 891  */
 892 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret)
 893 {
 894         struct crypto_attr_type *algt;
 895
 896         algt = crypto_get_attr_type(tb);
 897         if (IS_ERR(algt))
 898                 return PTR_ERR(algt);
 899
 900         if ((algt->type ^ type) & algt->mask)
 901                 return -EINVAL;
 902
 903         *mask_ret = crypto_algt_inherited_mask(algt);
 904         return 0;
 905 }
 906 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
 907
 908 const char *crypto_attr_alg_name(struct rtattr *rta)
 909 {
 910         struct crypto_attr_alg *alga;
 911
 912         if (!rta)
 913                 return ERR_PTR(-ENOENT);
 914         if (RTA_PAYLOAD(rta) < sizeof(*alga))
 915                 return ERR_PTR(-EINVAL);
 916         if (rta->rta_type != CRYPTOA_ALG)
 917                 return ERR_PTR(-EINVAL);
 918
 919         alga = RTA_DATA(rta);
 920         alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
 921
 922         return alga->name;
 923 }
 924 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
 925
 926 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
 927                         struct crypto_alg *alg)
 928 {
 929         if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
 930                      alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
 931                 return -ENAMETOOLONG;
 932
 933         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
 934                      name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 935                 return -ENAMETOOLONG;
 936
 937         return 0;
 938 }
 939 EXPORT_SYMBOL_GPL(crypto_inst_setname);
 940
 941 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
 942 {
 943         INIT_LIST_HEAD(&queue->list);
 944         queue->backlog = &queue->list;
 945         queue->qlen = 0;
 946         queue->max_qlen = max_qlen;
 947 }
 948 EXPORT_SYMBOL_GPL(crypto_init_queue);
 949
 950 int crypto_enqueue_request(struct crypto_queue *queue,
 951                            struct crypto_async_request *request)
 952 {
 953         int err = -EINPROGRESS;
 954
 955         if (unlikely(queue->qlen >= queue->max_qlen)) {
 956                 if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
 957                         err = -ENOSPC;
 958                         goto out;
 959                 }
 960                 err = -EBUSY;
 961                 if (queue->backlog == &queue->list)
 962                         queue->backlog = &request->list;
 963         }
 964
 965         queue->qlen++;
 966         list_add_tail(&request->list, &queue->list);
 967
 968 out:
 969         return err;
 970 }
 971 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
 972
 973 void crypto_enqueue_request_head(struct crypto_queue *queue,
 974                                  struct crypto_async_request *request)
 975 {
 976         if (unlikely(queue->qlen >= queue->max_qlen))
 977                 queue->backlog = queue->backlog->prev;
 978
 979         queue->qlen++;
 980         list_add(&request->list, &queue->list);
 981 }
 982 EXPORT_SYMBOL_GPL(crypto_enqueue_request_head);
 983
 984 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
 985 {
 986         struct list_head *request;
 987
 988         if (unlikely(!queue->qlen))
 989                 return NULL;
 990
 991         queue->qlen--;
 992
 993         if (queue->backlog != &queue->list)
 994                 queue->backlog = queue->backlog->next;
 995
 996         request = queue->list.next;
 997         list_del(request);
 998
 999         return list_entry(request, struct crypto_async_request, list);
1000 }
1001 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
1002
1003 static inline void crypto_inc_byte(u8 *a, unsigned int size)
1004 {
1005         u8 *b = (a + size);
1006         u8 c;
1007
1008         for (; size; size--) {
1009                 c = *--b + 1;
1010                 *b = c;
1011                 if (c)
1012                         break;
1013         }
1014 }
1015
1016 void crypto_inc(u8 *a, unsigned int size)
1017 {
1018         __be32 *b = (__be32 *)(a + size);
1019         u32 c;
1020
1021         if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
1022             IS_ALIGNED((unsigned long)b, __alignof__(*b)))
1023                 for (; size >= 4; size -= 4) {
1024                         c = be32_to_cpu(*--b) + 1;
1025                         *b = cpu_to_be32(c);
1026                         if (likely(c))
1027                                 return;
1028                 }
1029
1030         crypto_inc_byte(a, size);
1031 }
1032 EXPORT_SYMBOL_GPL(crypto_inc);
1033
1034 unsigned int crypto_alg_extsize(struct crypto_alg *alg)
1035 {
1036         return alg->cra_ctxsize +
1037                (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
1038 }
1039 EXPORT_SYMBOL_GPL(crypto_alg_extsize);
1040
1041 int crypto_type_has_alg(const char *name, const struct crypto_type *frontend,
1042                         u32 type, u32 mask)
1043 {
1044         int ret = 0;
1045         struct crypto_alg *alg = crypto_find_alg(name, frontend, type, mask);
1046
1047         if (!IS_ERR(alg)) {
1048                 crypto_mod_put(alg);
1049                 ret = 1;
1050         }
1051
1052         return ret;
1053 }
1054 EXPORT_SYMBOL_GPL(crypto_type_has_alg);
1055
1056 static void __init crypto_start_tests(void)
1057 {
1058         if (IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS))
1059                 return;
1060
1061         for (;;) {
1062                 struct crypto_larval *larval = NULL;
1063                 struct crypto_alg *q;
1064
1065                 down_write(&crypto_alg_sem);
1066
1067                 list_for_each_entry(q, &crypto_alg_list, cra_list) {
1068                         struct crypto_larval *l;
1069
1070                         if (!crypto_is_larval(q))
1071                                 continue;
1072
1073                         l = (void *)q;
1074
1075                         if (!crypto_is_test_larval(l))
1076                                 continue;
1077
1078                         if (l->test_started)
1079                                 continue;
1080
1081                         l->test_started = true;
1082                         larval = l;
1083                         break;
1084                 }
1085
1086                 up_write(&crypto_alg_sem);
1087
1088                 if (!larval)
1089                         break;
1090
1091                 crypto_wait_for_test(larval);
1092         }
1093
1094         set_crypto_boot_test_finished();
1095 }
1096
1097 static int __init crypto_algapi_init(void)
1098 {
1099         crypto_init_proc();
1100         crypto_start_tests();
1101         return 0;
1102 }
1103
1104 static void __exit crypto_algapi_exit(void)
1105 {
1106         crypto_exit_proc();
1107 }
1108
1109 /*
1110  * We run this at late_initcall so that all the built-in algorithms
1111  * have had a chance to register themselves first.
1112  */
1113 late_initcall(crypto_algapi_init);
1114 module_exit(crypto_algapi_exit);
1115
1116 MODULE_LICENSE("GPL");
1117 MODULE_DESCRIPTION("Cryptographic algorithms API");
1118 MODULE_SOFTDEP("pre: cryptomgr");