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_driver_name, alg->cra_driver_name) ||
 345                     !strcmp(q->cra_name, alg->cra_driver_name))
 346                         goto err;
 347         }
 348
 349         larval = crypto_alloc_test_larval(alg);
 350         if (IS_ERR(larval))
 351                 goto out;
 352
 353         list_add(&alg->cra_list, &crypto_alg_list);
 354
 355         if (larval) {
 356                 /* No cheating! */
 357                 alg->cra_flags &= ~CRYPTO_ALG_TESTED;
 358
 359                 list_add(&larval->alg.cra_list, &crypto_alg_list);
 360         } else {
 361                 alg->cra_flags |= CRYPTO_ALG_TESTED;
 362                 crypto_alg_finish_registration(alg, true, algs_to_put);
 363         }
 364
 365 out:
 366         return larval;
 367
 368 err:
 369         larval = ERR_PTR(ret);
 370         goto out;
 371 }
 372
 373 void crypto_alg_tested(const char *name, int err)
 374 {
 375         struct crypto_larval *test;
 376         struct crypto_alg *alg;
 377         struct crypto_alg *q;
 378         LIST_HEAD(list);
 379         bool best;
 380
 381         down_write(&crypto_alg_sem);
 382         list_for_each_entry(q, &crypto_alg_list, cra_list) {
 383                 if (crypto_is_moribund(q) || !crypto_is_larval(q))
 384                         continue;
 385
 386                 test = (struct crypto_larval *)q;
 387
 388                 if (!strcmp(q->cra_driver_name, name))
 389                         goto found;
 390         }
 391
 392         pr_err("alg: Unexpected test result for %s: %d\n", name, err);
 393         goto unlock;
 394
 395 found:
 396         q->cra_flags |= CRYPTO_ALG_DEAD;
 397         alg = test->adult;
 398
 399         if (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
 431 complete:
 432         complete_all(&test->completion);
 433
 434 unlock:
 435         up_write(&crypto_alg_sem);
 436
 437         crypto_remove_final(&list);
 438 }
 439 EXPORT_SYMBOL_GPL(crypto_alg_tested);
 440
 441 void crypto_remove_final(struct list_head *list)
 442 {
 443         struct crypto_alg *alg;
 444         struct crypto_alg *n;
 445
 446         list_for_each_entry_safe(alg, n, list, cra_list) {
 447                 list_del_init(&alg->cra_list);
 448                 crypto_alg_put(alg);
 449         }
 450 }
 451 EXPORT_SYMBOL_GPL(crypto_remove_final);
 452
 453 int crypto_register_alg(struct crypto_alg *alg)
 454 {
 455         struct crypto_larval *larval;
 456         LIST_HEAD(algs_to_put);
 457         bool test_started = false;
 458         int err;
 459
 460         alg->cra_flags &= ~CRYPTO_ALG_DEAD;
 461         err = crypto_check_alg(alg);
 462         if (err)
 463                 return err;
 464
 465         down_write(&crypto_alg_sem);
 466         larval = __crypto_register_alg(alg, &algs_to_put);
 467         if (!IS_ERR_OR_NULL(larval)) {
 468                 test_started = crypto_boot_test_finished();
 469                 larval->test_started = test_started;
 470         }
 471         up_write(&crypto_alg_sem);
 472
 473         if (IS_ERR(larval))
 474                 return PTR_ERR(larval);
 475         if (test_started)
 476                 crypto_wait_for_test(larval);
 477         crypto_remove_final(&algs_to_put);
 478         return 0;
 479 }
 480 EXPORT_SYMBOL_GPL(crypto_register_alg);
 481
 482 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
 483 {
 484         if (unlikely(list_empty(&alg->cra_list)))
 485                 return -ENOENT;
 486
 487         alg->cra_flags |= CRYPTO_ALG_DEAD;
 488
 489         list_del_init(&alg->cra_list);
 490         crypto_remove_spawns(alg, list, NULL);
 491
 492         return 0;
 493 }
 494
 495 void crypto_unregister_alg(struct crypto_alg *alg)
 496 {
 497         int ret;
 498         LIST_HEAD(list);
 499
 500         down_write(&crypto_alg_sem);
 501         ret = crypto_remove_alg(alg, &list);
 502         up_write(&crypto_alg_sem);
 503
 504         if (WARN(ret, "Algorithm %s is not registered", alg->cra_driver_name))
 505                 return;
 506
 507         if (WARN_ON(refcount_read(&alg->cra_refcnt) != 1))
 508                 return;
 509
 510         if (alg->cra_destroy)
 511                 alg->cra_destroy(alg);
 512
 513         crypto_remove_final(&list);
 514 }
 515 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
 516
 517 int crypto_register_algs(struct crypto_alg *algs, int count)
 518 {
 519         int i, ret;
 520
 521         for (i = 0; i < count; i++) {
 522                 ret = crypto_register_alg(&algs[i]);
 523                 if (ret)
 524                         goto err;
 525         }
 526
 527         return 0;
 528
 529 err:
 530         for (--i; i >= 0; --i)
 531                 crypto_unregister_alg(&algs[i]);
 532
 533         return ret;
 534 }
 535 EXPORT_SYMBOL_GPL(crypto_register_algs);
 536
 537 void crypto_unregister_algs(struct crypto_alg *algs, int count)
 538 {
 539         int i;
 540
 541         for (i = 0; i < count; i++)
 542                 crypto_unregister_alg(&algs[i]);
 543 }
 544 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
 545
 546 int crypto_register_template(struct crypto_template *tmpl)
 547 {
 548         struct crypto_template *q;
 549         int err = -EEXIST;
 550
 551         down_write(&crypto_alg_sem);
 552
 553         crypto_check_module_sig(tmpl->module);
 554
 555         list_for_each_entry(q, &crypto_template_list, list) {
 556                 if (q == tmpl)
 557                         goto out;
 558         }
 559
 560         list_add(&tmpl->list, &crypto_template_list);
 561         err = 0;
 562 out:
 563         up_write(&crypto_alg_sem);
 564         return err;
 565 }
 566 EXPORT_SYMBOL_GPL(crypto_register_template);
 567
 568 int crypto_register_templates(struct crypto_template *tmpls, int count)
 569 {
 570         int i, err;
 571
 572         for (i = 0; i < count; i++) {
 573                 err = crypto_register_template(&tmpls[i]);
 574                 if (err)
 575                         goto out;
 576         }
 577         return 0;
 578
 579 out:
 580         for (--i; i >= 0; --i)
 581                 crypto_unregister_template(&tmpls[i]);
 582         return err;
 583 }
 584 EXPORT_SYMBOL_GPL(crypto_register_templates);
 585
 586 void crypto_unregister_template(struct crypto_template *tmpl)
 587 {
 588         struct crypto_instance *inst;
 589         struct hlist_node *n;
 590         struct hlist_head *list;
 591         LIST_HEAD(users);
 592
 593         down_write(&crypto_alg_sem);
 594
 595         BUG_ON(list_empty(&tmpl->list));
 596         list_del_init(&tmpl->list);
 597
 598         list = &tmpl->instances;
 599         hlist_for_each_entry(inst, list, list) {
 600                 int err = crypto_remove_alg(&inst->alg, &users);
 601
 602                 BUG_ON(err);
 603         }
 604
 605         up_write(&crypto_alg_sem);
 606
 607         hlist_for_each_entry_safe(inst, n, list, list) {
 608                 BUG_ON(refcount_read(&inst->alg.cra_refcnt) != 1);
 609                 crypto_free_instance(inst);
 610         }
 611         crypto_remove_final(&users);
 612 }
 613 EXPORT_SYMBOL_GPL(crypto_unregister_template);
 614
 615 void crypto_unregister_templates(struct crypto_template *tmpls, int count)
 616 {
 617         int i;
 618
 619         for (i = count - 1; i >= 0; --i)
 620                 crypto_unregister_template(&tmpls[i]);
 621 }
 622 EXPORT_SYMBOL_GPL(crypto_unregister_templates);
 623
 624 static struct crypto_template *__crypto_lookup_template(const char *name)
 625 {
 626         struct crypto_template *q, *tmpl = NULL;
 627
 628         down_read(&crypto_alg_sem);
 629         list_for_each_entry(q, &crypto_template_list, list) {
 630                 if (strcmp(q->name, name))
 631                         continue;
 632                 if (unlikely(!crypto_tmpl_get(q)))
 633                         continue;
 634
 635                 tmpl = q;
 636                 break;
 637         }
 638         up_read(&crypto_alg_sem);
 639
 640         return tmpl;
 641 }
 642
 643 struct crypto_template *crypto_lookup_template(const char *name)
 644 {
 645         return try_then_request_module(__crypto_lookup_template(name),
 646                                        "crypto-%s", name);
 647 }
 648 EXPORT_SYMBOL_GPL(crypto_lookup_template);
 649
 650 int crypto_register_instance(struct crypto_template *tmpl,
 651                              struct crypto_instance *inst)
 652 {
 653         struct crypto_larval *larval;
 654         struct crypto_spawn *spawn;
 655         u32 fips_internal = 0;
 656         LIST_HEAD(algs_to_put);
 657         int err;
 658
 659         err = crypto_check_alg(&inst->alg);
 660         if (err)
 661                 return err;
 662
 663         inst->alg.cra_module = tmpl->module;
 664         inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
 665
 666         down_write(&crypto_alg_sem);
 667
 668         larval = ERR_PTR(-EAGAIN);
 669         for (spawn = inst->spawns; spawn;) {
 670                 struct crypto_spawn *next;
 671
 672                 if (spawn->dead)
 673                         goto unlock;
 674
 675                 next = spawn->next;
 676                 spawn->inst = inst;
 677                 spawn->registered = true;
 678
 679                 fips_internal |= spawn->alg->cra_flags;
 680
 681                 crypto_mod_put(spawn->alg);
 682
 683                 spawn = next;
 684         }
 685
 686         inst->alg.cra_flags |= (fips_internal & CRYPTO_ALG_FIPS_INTERNAL);
 687
 688         larval = __crypto_register_alg(&inst->alg, &algs_to_put);
 689         if (IS_ERR(larval))
 690                 goto unlock;
 691         else if (larval)
 692                 larval->test_started = true;
 693
 694         hlist_add_head(&inst->list, &tmpl->instances);
 695         inst->tmpl = tmpl;
 696
 697 unlock:
 698         up_write(&crypto_alg_sem);
 699
 700         if (IS_ERR(larval))
 701                 return PTR_ERR(larval);
 702         if (larval)
 703                 crypto_wait_for_test(larval);
 704         crypto_remove_final(&algs_to_put);
 705         return 0;
 706 }
 707 EXPORT_SYMBOL_GPL(crypto_register_instance);
 708
 709 void crypto_unregister_instance(struct crypto_instance *inst)
 710 {
 711         LIST_HEAD(list);
 712
 713         down_write(&crypto_alg_sem);
 714
 715         crypto_remove_spawns(&inst->alg, &list, NULL);
 716         crypto_remove_instance(inst, &list);
 717
 718         up_write(&crypto_alg_sem);
 719
 720         crypto_remove_final(&list);
 721 }
 722 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
 723
 724 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
 725                       const char *name, u32 type, u32 mask)
 726 {
 727         struct crypto_alg *alg;
 728         int err = -EAGAIN;
 729
 730         if (WARN_ON_ONCE(inst == NULL))
 731                 return -EINVAL;
 732
 733         /* Allow the result of crypto_attr_alg_name() to be passed directly */
 734         if (IS_ERR(name))
 735                 return PTR_ERR(name);
 736
 737         alg = crypto_find_alg(name, spawn->frontend,
 738                               type | CRYPTO_ALG_FIPS_INTERNAL, mask);
 739         if (IS_ERR(alg))
 740                 return PTR_ERR(alg);
 741
 742         down_write(&crypto_alg_sem);
 743         if (!crypto_is_moribund(alg)) {
 744                 list_add(&spawn->list, &alg->cra_users);
 745                 spawn->alg = alg;
 746                 spawn->mask = mask;
 747                 spawn->next = inst->spawns;
 748                 inst->spawns = spawn;
 749                 inst->alg.cra_flags |=
 750                         (alg->cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
 751                 err = 0;
 752         }
 753         up_write(&crypto_alg_sem);
 754         if (err)
 755                 crypto_mod_put(alg);
 756         return err;
 757 }
 758 EXPORT_SYMBOL_GPL(crypto_grab_spawn);
 759
 760 void crypto_drop_spawn(struct crypto_spawn *spawn)
 761 {
 762         if (!spawn->alg) /* not yet initialized? */
 763                 return;
 764
 765         down_write(&crypto_alg_sem);
 766         if (!spawn->dead)
 767                 list_del(&spawn->list);
 768         up_write(&crypto_alg_sem);
 769
 770         if (!spawn->registered)
 771                 crypto_mod_put(spawn->alg);
 772 }
 773 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
 774
 775 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
 776 {
 777         struct crypto_alg *alg = ERR_PTR(-EAGAIN);
 778         struct crypto_alg *target;
 779         bool shoot = false;
 780
 781         down_read(&crypto_alg_sem);
 782         if (!spawn->dead) {
 783                 alg = spawn->alg;
 784                 if (!crypto_mod_get(alg)) {
 785                         target = crypto_alg_get(alg);
 786                         shoot = true;
 787                         alg = ERR_PTR(-EAGAIN);
 788                 }
 789         }
 790         up_read(&crypto_alg_sem);
 791
 792         if (shoot) {
 793                 crypto_shoot_alg(target);
 794                 crypto_alg_put(target);
 795         }
 796
 797         return alg;
 798 }
 799
 800 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
 801                                     u32 mask)
 802 {
 803         struct crypto_alg *alg;
 804         struct crypto_tfm *tfm;
 805
 806         alg = crypto_spawn_alg(spawn);
 807         if (IS_ERR(alg))
 808                 return ERR_CAST(alg);
 809
 810         tfm = ERR_PTR(-EINVAL);
 811         if (unlikely((alg->cra_flags ^ type) & mask))
 812                 goto out_put_alg;
 813
 814         tfm = __crypto_alloc_tfm(alg, type, mask);
 815         if (IS_ERR(tfm))
 816                 goto out_put_alg;
 817
 818         return tfm;
 819
 820 out_put_alg:
 821         crypto_mod_put(alg);
 822         return tfm;
 823 }
 824 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
 825
 826 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
 827 {
 828         struct crypto_alg *alg;
 829         struct crypto_tfm *tfm;
 830
 831         alg = crypto_spawn_alg(spawn);
 832         if (IS_ERR(alg))
 833                 return ERR_CAST(alg);
 834
 835         tfm = crypto_create_tfm(alg, spawn->frontend);
 836         if (IS_ERR(tfm))
 837                 goto out_put_alg;
 838
 839         return tfm;
 840
 841 out_put_alg:
 842         crypto_mod_put(alg);
 843         return tfm;
 844 }
 845 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
 846
 847 int crypto_register_notifier(struct notifier_block *nb)
 848 {
 849         return blocking_notifier_chain_register(&crypto_chain, nb);
 850 }
 851 EXPORT_SYMBOL_GPL(crypto_register_notifier);
 852
 853 int crypto_unregister_notifier(struct notifier_block *nb)
 854 {
 855         return blocking_notifier_chain_unregister(&crypto_chain, nb);
 856 }
 857 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
 858
 859 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
 860 {
 861         struct rtattr *rta = tb[0];
 862         struct crypto_attr_type *algt;
 863
 864         if (!rta)
 865                 return ERR_PTR(-ENOENT);
 866         if (RTA_PAYLOAD(rta) < sizeof(*algt))
 867                 return ERR_PTR(-EINVAL);
 868         if (rta->rta_type != CRYPTOA_TYPE)
 869                 return ERR_PTR(-EINVAL);
 870
 871         algt = RTA_DATA(rta);
 872
 873         return algt;
 874 }
 875 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
 876
 877 /**
 878  * crypto_check_attr_type() - check algorithm type and compute inherited mask
 879  * @tb: the template parameters
 880  * @type: the algorithm type the template would be instantiated as
 881  * @mask_ret: (output) the mask that should be passed to crypto_grab_*()
 882  *            to restrict the flags of any inner algorithms
 883  *
 884  * Validate that the algorithm type the user requested is compatible with the
 885  * one the template would actually be instantiated as.  E.g., if the user is
 886  * doing crypto_alloc_shash("cbc(aes)", ...), this would return an error because
 887  * the "cbc" template creates an "skcipher" algorithm, not an "shash" algorithm.
 888  *
 889  * Also compute the mask to use to restrict the flags of any inner algorithms.
 890  *
 891  * Return: 0 on success; -errno on failure
 892  */
 893 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret)
 894 {
 895         struct crypto_attr_type *algt;
 896
 897         algt = crypto_get_attr_type(tb);
 898         if (IS_ERR(algt))
 899                 return PTR_ERR(algt);
 900
 901         if ((algt->type ^ type) & algt->mask)
 902                 return -EINVAL;
 903
 904         *mask_ret = crypto_algt_inherited_mask(algt);
 905         return 0;
 906 }
 907 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
 908
 909 const char *crypto_attr_alg_name(struct rtattr *rta)
 910 {
 911         struct crypto_attr_alg *alga;
 912
 913         if (!rta)
 914                 return ERR_PTR(-ENOENT);
 915         if (RTA_PAYLOAD(rta) < sizeof(*alga))
 916                 return ERR_PTR(-EINVAL);
 917         if (rta->rta_type != CRYPTOA_ALG)
 918                 return ERR_PTR(-EINVAL);
 919
 920         alga = RTA_DATA(rta);
 921         alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
 922
 923         return alga->name;
 924 }
 925 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
 926
 927 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
 928                         struct crypto_alg *alg)
 929 {
 930         if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
 931                      alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
 932                 return -ENAMETOOLONG;
 933
 934         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
 935                      name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 936                 return -ENAMETOOLONG;
 937
 938         return 0;
 939 }
 940 EXPORT_SYMBOL_GPL(crypto_inst_setname);
 941
 942 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
 943 {
 944         INIT_LIST_HEAD(&queue->list);
 945         queue->backlog = &queue->list;
 946         queue->qlen = 0;
 947         queue->max_qlen = max_qlen;
 948 }
 949 EXPORT_SYMBOL_GPL(crypto_init_queue);
 950
 951 int crypto_enqueue_request(struct crypto_queue *queue,
 952                            struct crypto_async_request *request)
 953 {
 954         int err = -EINPROGRESS;
 955
 956         if (unlikely(queue->qlen >= queue->max_qlen)) {
 957                 if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
 958                         err = -ENOSPC;
 959                         goto out;
 960                 }
 961                 err = -EBUSY;
 962                 if (queue->backlog == &queue->list)
 963                         queue->backlog = &request->list;
 964         }
 965
 966         queue->qlen++;
 967         list_add_tail(&request->list, &queue->list);
 968
 969 out:
 970         return err;
 971 }
 972 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
 973
 974 void crypto_enqueue_request_head(struct crypto_queue *queue,
 975                                  struct crypto_async_request *request)
 976 {
 977         if (unlikely(queue->qlen >= queue->max_qlen))
 978                 queue->backlog = queue->backlog->prev;
 979
 980         queue->qlen++;
 981         list_add(&request->list, &queue->list);
 982 }
 983 EXPORT_SYMBOL_GPL(crypto_enqueue_request_head);
 984
 985 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
 986 {
 987         struct list_head *request;
 988
 989         if (unlikely(!queue->qlen))
 990                 return NULL;
 991
 992         queue->qlen--;
 993
 994         if (queue->backlog != &queue->list)
 995                 queue->backlog = queue->backlog->next;
 996
 997         request = queue->list.next;
 998         list_del(request);
 999
1000         return list_entry(request, struct crypto_async_request, list);
1001 }
1002 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
1003
1004 static inline void crypto_inc_byte(u8 *a, unsigned int size)
1005 {
1006         u8 *b = (a + size);
1007         u8 c;
1008
1009         for (; size; size--) {
1010                 c = *--b + 1;
1011                 *b = c;
1012                 if (c)
1013                         break;
1014         }
1015 }
1016
1017 void crypto_inc(u8 *a, unsigned int size)
1018 {
1019         __be32 *b = (__be32 *)(a + size);
1020         u32 c;
1021
1022         if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
1023             IS_ALIGNED((unsigned long)b, __alignof__(*b)))
1024                 for (; size >= 4; size -= 4) {
1025                         c = be32_to_cpu(*--b) + 1;
1026                         *b = cpu_to_be32(c);
1027                         if (likely(c))
1028                                 return;
1029                 }
1030
1031         crypto_inc_byte(a, size);
1032 }
1033 EXPORT_SYMBOL_GPL(crypto_inc);
1034
1035 unsigned int crypto_alg_extsize(struct crypto_alg *alg)
1036 {
1037         return alg->cra_ctxsize +
1038                (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
1039 }
1040 EXPORT_SYMBOL_GPL(crypto_alg_extsize);
1041
1042 int crypto_type_has_alg(const char *name, const struct crypto_type *frontend,
1043                         u32 type, u32 mask)
1044 {
1045         int ret = 0;
1046         struct crypto_alg *alg = crypto_find_alg(name, frontend, type, mask);
1047
1048         if (!IS_ERR(alg)) {
1049                 crypto_mod_put(alg);
1050                 ret = 1;
1051         }
1052
1053         return ret;
1054 }
1055 EXPORT_SYMBOL_GPL(crypto_type_has_alg);
1056
1057 static void __init crypto_start_tests(void)
1058 {
1059         if (IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS))
1060                 return;
1061
1062         for (;;) {
1063                 struct crypto_larval *larval = NULL;
1064                 struct crypto_alg *q;
1065
1066                 down_write(&crypto_alg_sem);
1067
1068                 list_for_each_entry(q, &crypto_alg_list, cra_list) {
1069                         struct crypto_larval *l;
1070
1071                         if (!crypto_is_larval(q))
1072                                 continue;
1073
1074                         l = (void *)q;
1075
1076                         if (!crypto_is_test_larval(l))
1077                                 continue;
1078
1079                         if (l->test_started)
1080                                 continue;
1081
1082                         l->test_started = true;
1083                         larval = l;
1084                         break;
1085                 }
1086
1087                 up_write(&crypto_alg_sem);
1088
1089                 if (!larval)
1090                         break;
1091
1092                 crypto_wait_for_test(larval);
1093         }
1094
1095         set_crypto_boot_test_finished();
1096 }
1097
1098 static int __init crypto_algapi_init(void)
1099 {
1100         crypto_init_proc();
1101         crypto_start_tests();
1102         return 0;
1103 }
1104
1105 static void __exit crypto_algapi_exit(void)
1106 {
1107         crypto_exit_proc();
1108 }
1109
1110 /*
1111  * We run this at late_initcall so that all the built-in algorithms
1112  * have had a chance to register themselves first.
1113  */
1114 late_initcall(crypto_algapi_init);
1115 module_exit(crypto_algapi_exit);
1116
1117 MODULE_LICENSE("GPL");
1118 MODULE_DESCRIPTION("Cryptographic algorithms API");
1119 MODULE_SOFTDEP("pre: cryptomgr");