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