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 <[email protected]>
   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                                            struct list_head *algs_to_put)
 239 {
 240         struct crypto_alg *q;
 241
 242         list_for_each_entry(q, &crypto_alg_list, cra_list) {
 243                 if (q == alg)
 244                         continue;
 245
 246                 if (crypto_is_moribund(q))
 247                         continue;
 248
 249                 if (crypto_is_larval(q))
 250                         continue;
 251
 252                 if (strcmp(alg->cra_name, q->cra_name))
 253                         continue;
 254
 255                 if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
 256                     q->cra_priority > alg->cra_priority)
 257                         continue;
 258
 259                 crypto_remove_spawns(q, algs_to_put, alg);
 260         }
 261
 262         crypto_notify(CRYPTO_MSG_ALG_LOADED, alg);
 263 }
 264
 265 static struct crypto_larval *crypto_alloc_test_larval(struct crypto_alg *alg)
 266 {
 267         struct crypto_larval *larval;
 268
 269         if (!IS_ENABLED(CONFIG_CRYPTO_MANAGER) ||
 270             IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS) ||
 271             (alg->cra_flags & CRYPTO_ALG_INTERNAL))
 272                 return NULL; /* No self-test needed */
 273
 274         larval = crypto_larval_alloc(alg->cra_name,
 275                                      alg->cra_flags | CRYPTO_ALG_TESTED, 0);
 276         if (IS_ERR(larval))
 277                 return larval;
 278
 279         larval->adult = crypto_mod_get(alg);
 280         if (!larval->adult) {
 281                 kfree(larval);
 282                 return ERR_PTR(-ENOENT);
 283         }
 284
 285         refcount_set(&larval->alg.cra_refcnt, 1);
 286         memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
 287                CRYPTO_MAX_ALG_NAME);
 288         larval->alg.cra_priority = alg->cra_priority;
 289
 290         return larval;
 291 }
 292
 293 static struct crypto_larval *
 294 __crypto_register_alg(struct crypto_alg *alg, struct list_head *algs_to_put)
 295 {
 296         struct crypto_alg *q;
 297         struct crypto_larval *larval;
 298         int ret = -EAGAIN;
 299
 300         if (crypto_is_dead(alg))
 301                 goto err;
 302
 303         INIT_LIST_HEAD(&alg->cra_users);
 304
 305         ret = -EEXIST;
 306
 307         list_for_each_entry(q, &crypto_alg_list, cra_list) {
 308                 if (q == alg)
 309                         goto err;
 310
 311                 if (crypto_is_moribund(q))
 312                         continue;
 313
 314                 if (crypto_is_larval(q)) {
 315                         if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
 316                                 goto err;
 317                         continue;
 318                 }
 319
 320                 if (!strcmp(q->cra_driver_name, alg->cra_name) ||
 321                     !strcmp(q->cra_driver_name, alg->cra_driver_name) ||
 322                     !strcmp(q->cra_name, alg->cra_driver_name))
 323                         goto err;
 324         }
 325
 326         larval = crypto_alloc_test_larval(alg);
 327         if (IS_ERR(larval))
 328                 goto out;
 329
 330         list_add(&alg->cra_list, &crypto_alg_list);
 331
 332         if (larval) {
 333                 /* No cheating! */
 334                 alg->cra_flags &= ~CRYPTO_ALG_TESTED;
 335
 336                 list_add(&larval->alg.cra_list, &crypto_alg_list);
 337         } else {
 338                 alg->cra_flags |= CRYPTO_ALG_TESTED;
 339                 crypto_alg_finish_registration(alg, algs_to_put);
 340         }
 341
 342 out:
 343         return larval;
 344
 345 err:
 346         larval = ERR_PTR(ret);
 347         goto out;
 348 }
 349
 350 void crypto_alg_tested(const char *name, int err)
 351 {
 352         struct crypto_larval *test;
 353         struct crypto_alg *alg;
 354         struct crypto_alg *q;
 355         LIST_HEAD(list);
 356
 357         down_write(&crypto_alg_sem);
 358         list_for_each_entry(q, &crypto_alg_list, cra_list) {
 359                 if (crypto_is_moribund(q) || !crypto_is_larval(q))
 360                         continue;
 361
 362                 test = (struct crypto_larval *)q;
 363
 364                 if (!strcmp(q->cra_driver_name, name))
 365                         goto found;
 366         }
 367
 368         pr_err("alg: Unexpected test result for %s: %d\n", name, err);
 369         up_write(&crypto_alg_sem);
 370         return;
 371
 372 found:
 373         q->cra_flags |= CRYPTO_ALG_DEAD;
 374         alg = test->adult;
 375
 376         if (list_empty(&alg->cra_list))
 377                 goto complete;
 378
 379         if (err == -ECANCELED)
 380                 alg->cra_flags |= CRYPTO_ALG_FIPS_INTERNAL;
 381         else if (err)
 382                 goto complete;
 383         else
 384                 alg->cra_flags &= ~CRYPTO_ALG_FIPS_INTERNAL;
 385
 386         alg->cra_flags |= CRYPTO_ALG_TESTED;
 387
 388         crypto_alg_finish_registration(alg, &list);
 389
 390 complete:
 391         list_del_init(&test->alg.cra_list);
 392         complete_all(&test->completion);
 393
 394         up_write(&crypto_alg_sem);
 395
 396         crypto_alg_put(&test->alg);
 397         crypto_remove_final(&list);
 398 }
 399 EXPORT_SYMBOL_GPL(crypto_alg_tested);
 400
 401 void crypto_remove_final(struct list_head *list)
 402 {
 403         struct crypto_alg *alg;
 404         struct crypto_alg *n;
 405
 406         list_for_each_entry_safe(alg, n, list, cra_list) {
 407                 list_del_init(&alg->cra_list);
 408                 crypto_alg_put(alg);
 409         }
 410 }
 411 EXPORT_SYMBOL_GPL(crypto_remove_final);
 412
 413 int crypto_register_alg(struct crypto_alg *alg)
 414 {
 415         struct crypto_larval *larval;
 416         LIST_HEAD(algs_to_put);
 417         int err;
 418
 419         alg->cra_flags &= ~CRYPTO_ALG_DEAD;
 420         err = crypto_check_alg(alg);
 421         if (err)
 422                 return err;
 423
 424         down_write(&crypto_alg_sem);
 425         larval = __crypto_register_alg(alg, &algs_to_put);
 426         if (!IS_ERR_OR_NULL(larval)) {
 427                 bool test_started = crypto_boot_test_finished();
 428
 429                 larval->test_started = test_started;
 430                 if (test_started)
 431                         crypto_schedule_test(larval);
 432         }
 433         up_write(&crypto_alg_sem);
 434
 435         if (IS_ERR(larval))
 436                 return PTR_ERR(larval);
 437         crypto_remove_final(&algs_to_put);
 438         return 0;
 439 }
 440 EXPORT_SYMBOL_GPL(crypto_register_alg);
 441
 442 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
 443 {
 444         if (unlikely(list_empty(&alg->cra_list)))
 445                 return -ENOENT;
 446
 447         alg->cra_flags |= CRYPTO_ALG_DEAD;
 448
 449         list_del_init(&alg->cra_list);
 450         crypto_remove_spawns(alg, list, NULL);
 451
 452         return 0;
 453 }
 454
 455 void crypto_unregister_alg(struct crypto_alg *alg)
 456 {
 457         int ret;
 458         LIST_HEAD(list);
 459
 460         down_write(&crypto_alg_sem);
 461         ret = crypto_remove_alg(alg, &list);
 462         up_write(&crypto_alg_sem);
 463
 464         if (WARN(ret, "Algorithm %s is not registered", alg->cra_driver_name))
 465                 return;
 466
 467         if (WARN_ON(refcount_read(&alg->cra_refcnt) != 1))
 468                 return;
 469
 470         if (alg->cra_destroy)
 471                 alg->cra_destroy(alg);
 472
 473         crypto_remove_final(&list);
 474 }
 475 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
 476
 477 int crypto_register_algs(struct crypto_alg *algs, int count)
 478 {
 479         int i, ret;
 480
 481         for (i = 0; i < count; i++) {
 482                 ret = crypto_register_alg(&algs[i]);
 483                 if (ret)
 484                         goto err;
 485         }
 486
 487         return 0;
 488
 489 err:
 490         for (--i; i >= 0; --i)
 491                 crypto_unregister_alg(&algs[i]);
 492
 493         return ret;
 494 }
 495 EXPORT_SYMBOL_GPL(crypto_register_algs);
 496
 497 void crypto_unregister_algs(struct crypto_alg *algs, int count)
 498 {
 499         int i;
 500
 501         for (i = 0; i < count; i++)
 502                 crypto_unregister_alg(&algs[i]);
 503 }
 504 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
 505
 506 int crypto_register_template(struct crypto_template *tmpl)
 507 {
 508         struct crypto_template *q;
 509         int err = -EEXIST;
 510
 511         down_write(&crypto_alg_sem);
 512
 513         crypto_check_module_sig(tmpl->module);
 514
 515         list_for_each_entry(q, &crypto_template_list, list) {
 516                 if (q == tmpl)
 517                         goto out;
 518         }
 519
 520         list_add(&tmpl->list, &crypto_template_list);
 521         err = 0;
 522 out:
 523         up_write(&crypto_alg_sem);
 524         return err;
 525 }
 526 EXPORT_SYMBOL_GPL(crypto_register_template);
 527
 528 int crypto_register_templates(struct crypto_template *tmpls, int count)
 529 {
 530         int i, err;
 531
 532         for (i = 0; i < count; i++) {
 533                 err = crypto_register_template(&tmpls[i]);
 534                 if (err)
 535                         goto out;
 536         }
 537         return 0;
 538
 539 out:
 540         for (--i; i >= 0; --i)
 541                 crypto_unregister_template(&tmpls[i]);
 542         return err;
 543 }
 544 EXPORT_SYMBOL_GPL(crypto_register_templates);
 545
 546 void crypto_unregister_template(struct crypto_template *tmpl)
 547 {
 548         struct crypto_instance *inst;
 549         struct hlist_node *n;
 550         struct hlist_head *list;
 551         LIST_HEAD(users);
 552
 553         down_write(&crypto_alg_sem);
 554
 555         BUG_ON(list_empty(&tmpl->list));
 556         list_del_init(&tmpl->list);
 557
 558         list = &tmpl->instances;
 559         hlist_for_each_entry(inst, list, list) {
 560                 int err = crypto_remove_alg(&inst->alg, &users);
 561
 562                 BUG_ON(err);
 563         }
 564
 565         up_write(&crypto_alg_sem);
 566
 567         hlist_for_each_entry_safe(inst, n, list, list) {
 568                 BUG_ON(refcount_read(&inst->alg.cra_refcnt) != 1);
 569                 crypto_free_instance(inst);
 570         }
 571         crypto_remove_final(&users);
 572 }
 573 EXPORT_SYMBOL_GPL(crypto_unregister_template);
 574
 575 void crypto_unregister_templates(struct crypto_template *tmpls, int count)
 576 {
 577         int i;
 578
 579         for (i = count - 1; i >= 0; --i)
 580                 crypto_unregister_template(&tmpls[i]);
 581 }
 582 EXPORT_SYMBOL_GPL(crypto_unregister_templates);
 583
 584 static struct crypto_template *__crypto_lookup_template(const char *name)
 585 {
 586         struct crypto_template *q, *tmpl = NULL;
 587
 588         down_read(&crypto_alg_sem);
 589         list_for_each_entry(q, &crypto_template_list, list) {
 590                 if (strcmp(q->name, name))
 591                         continue;
 592                 if (unlikely(!crypto_tmpl_get(q)))
 593                         continue;
 594
 595                 tmpl = q;
 596                 break;
 597         }
 598         up_read(&crypto_alg_sem);
 599
 600         return tmpl;
 601 }
 602
 603 struct crypto_template *crypto_lookup_template(const char *name)
 604 {
 605         return try_then_request_module(__crypto_lookup_template(name),
 606                                        "crypto-%s", name);
 607 }
 608 EXPORT_SYMBOL_GPL(crypto_lookup_template);
 609
 610 int crypto_register_instance(struct crypto_template *tmpl,
 611                              struct crypto_instance *inst)
 612 {
 613         struct crypto_larval *larval;
 614         struct crypto_spawn *spawn;
 615         u32 fips_internal = 0;
 616         LIST_HEAD(algs_to_put);
 617         int err;
 618
 619         err = crypto_check_alg(&inst->alg);
 620         if (err)
 621                 return err;
 622
 623         inst->alg.cra_module = tmpl->module;
 624         inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
 625
 626         down_write(&crypto_alg_sem);
 627
 628         larval = ERR_PTR(-EAGAIN);
 629         for (spawn = inst->spawns; spawn;) {
 630                 struct crypto_spawn *next;
 631
 632                 if (spawn->dead)
 633                         goto unlock;
 634
 635                 next = spawn->next;
 636                 spawn->inst = inst;
 637                 spawn->registered = true;
 638
 639                 fips_internal |= spawn->alg->cra_flags;
 640
 641                 crypto_mod_put(spawn->alg);
 642
 643                 spawn = next;
 644         }
 645
 646         inst->alg.cra_flags |= (fips_internal & CRYPTO_ALG_FIPS_INTERNAL);
 647
 648         larval = __crypto_register_alg(&inst->alg, &algs_to_put);
 649         if (IS_ERR(larval))
 650                 goto unlock;
 651         else if (larval) {
 652                 larval->test_started = true;
 653                 crypto_schedule_test(larval);
 654         }
 655
 656         hlist_add_head(&inst->list, &tmpl->instances);
 657         inst->tmpl = tmpl;
 658
 659 unlock:
 660         up_write(&crypto_alg_sem);
 661
 662         if (IS_ERR(larval))
 663                 return PTR_ERR(larval);
 664         crypto_remove_final(&algs_to_put);
 665         return 0;
 666 }
 667 EXPORT_SYMBOL_GPL(crypto_register_instance);
 668
 669 void crypto_unregister_instance(struct crypto_instance *inst)
 670 {
 671         LIST_HEAD(list);
 672
 673         down_write(&crypto_alg_sem);
 674
 675         crypto_remove_spawns(&inst->alg, &list, NULL);
 676         crypto_remove_instance(inst, &list);
 677
 678         up_write(&crypto_alg_sem);
 679
 680         crypto_remove_final(&list);
 681 }
 682 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
 683
 684 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
 685                       const char *name, u32 type, u32 mask)
 686 {
 687         struct crypto_alg *alg;
 688         int err = -EAGAIN;
 689
 690         if (WARN_ON_ONCE(inst == NULL))
 691                 return -EINVAL;
 692
 693         /* Allow the result of crypto_attr_alg_name() to be passed directly */
 694         if (IS_ERR(name))
 695                 return PTR_ERR(name);
 696
 697         alg = crypto_find_alg(name, spawn->frontend,
 698                               type | CRYPTO_ALG_FIPS_INTERNAL, mask);
 699         if (IS_ERR(alg))
 700                 return PTR_ERR(alg);
 701
 702         down_write(&crypto_alg_sem);
 703         if (!crypto_is_moribund(alg)) {
 704                 list_add(&spawn->list, &alg->cra_users);
 705                 spawn->alg = alg;
 706                 spawn->mask = mask;
 707                 spawn->next = inst->spawns;
 708                 inst->spawns = spawn;
 709                 inst->alg.cra_flags |=
 710                         (alg->cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
 711                 err = 0;
 712         }
 713         up_write(&crypto_alg_sem);
 714         if (err)
 715                 crypto_mod_put(alg);
 716         return err;
 717 }
 718 EXPORT_SYMBOL_GPL(crypto_grab_spawn);
 719
 720 void crypto_drop_spawn(struct crypto_spawn *spawn)
 721 {
 722         if (!spawn->alg) /* not yet initialized? */
 723                 return;
 724
 725         down_write(&crypto_alg_sem);
 726         if (!spawn->dead)
 727                 list_del(&spawn->list);
 728         up_write(&crypto_alg_sem);
 729
 730         if (!spawn->registered)
 731                 crypto_mod_put(spawn->alg);
 732 }
 733 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
 734
 735 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
 736 {
 737         struct crypto_alg *alg = ERR_PTR(-EAGAIN);
 738         struct crypto_alg *target;
 739         bool shoot = false;
 740
 741         down_read(&crypto_alg_sem);
 742         if (!spawn->dead) {
 743                 alg = spawn->alg;
 744                 if (!crypto_mod_get(alg)) {
 745                         target = crypto_alg_get(alg);
 746                         shoot = true;
 747                         alg = ERR_PTR(-EAGAIN);
 748                 }
 749         }
 750         up_read(&crypto_alg_sem);
 751
 752         if (shoot) {
 753                 crypto_shoot_alg(target);
 754                 crypto_alg_put(target);
 755         }
 756
 757         return alg;
 758 }
 759
 760 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
 761                                     u32 mask)
 762 {
 763         struct crypto_alg *alg;
 764         struct crypto_tfm *tfm;
 765
 766         alg = crypto_spawn_alg(spawn);
 767         if (IS_ERR(alg))
 768                 return ERR_CAST(alg);
 769
 770         tfm = ERR_PTR(-EINVAL);
 771         if (unlikely((alg->cra_flags ^ type) & mask))
 772                 goto out_put_alg;
 773
 774         tfm = __crypto_alloc_tfm(alg, type, mask);
 775         if (IS_ERR(tfm))
 776                 goto out_put_alg;
 777
 778         return tfm;
 779
 780 out_put_alg:
 781         crypto_mod_put(alg);
 782         return tfm;
 783 }
 784 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
 785
 786 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
 787 {
 788         struct crypto_alg *alg;
 789         struct crypto_tfm *tfm;
 790
 791         alg = crypto_spawn_alg(spawn);
 792         if (IS_ERR(alg))
 793                 return ERR_CAST(alg);
 794
 795         tfm = crypto_create_tfm(alg, spawn->frontend);
 796         if (IS_ERR(tfm))
 797                 goto out_put_alg;
 798
 799         return tfm;
 800
 801 out_put_alg:
 802         crypto_mod_put(alg);
 803         return tfm;
 804 }
 805 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
 806
 807 int crypto_register_notifier(struct notifier_block *nb)
 808 {
 809         return blocking_notifier_chain_register(&crypto_chain, nb);
 810 }
 811 EXPORT_SYMBOL_GPL(crypto_register_notifier);
 812
 813 int crypto_unregister_notifier(struct notifier_block *nb)
 814 {
 815         return blocking_notifier_chain_unregister(&crypto_chain, nb);
 816 }
 817 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
 818
 819 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
 820 {
 821         struct rtattr *rta = tb[0];
 822         struct crypto_attr_type *algt;
 823
 824         if (!rta)
 825                 return ERR_PTR(-ENOENT);
 826         if (RTA_PAYLOAD(rta) < sizeof(*algt))
 827                 return ERR_PTR(-EINVAL);
 828         if (rta->rta_type != CRYPTOA_TYPE)
 829                 return ERR_PTR(-EINVAL);
 830
 831         algt = RTA_DATA(rta);
 832
 833         return algt;
 834 }
 835 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
 836
 837 /**
 838  * crypto_check_attr_type() - check algorithm type and compute inherited mask
 839  * @tb: the template parameters
 840  * @type: the algorithm type the template would be instantiated as
 841  * @mask_ret: (output) the mask that should be passed to crypto_grab_*()
 842  *            to restrict the flags of any inner algorithms
 843  *
 844  * Validate that the algorithm type the user requested is compatible with the
 845  * one the template would actually be instantiated as.  E.g., if the user is
 846  * doing crypto_alloc_shash("cbc(aes)", ...), this would return an error because
 847  * the "cbc" template creates an "skcipher" algorithm, not an "shash" algorithm.
 848  *
 849  * Also compute the mask to use to restrict the flags of any inner algorithms.
 850  *
 851  * Return: 0 on success; -errno on failure
 852  */
 853 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret)
 854 {
 855         struct crypto_attr_type *algt;
 856
 857         algt = crypto_get_attr_type(tb);
 858         if (IS_ERR(algt))
 859                 return PTR_ERR(algt);
 860
 861         if ((algt->type ^ type) & algt->mask)
 862                 return -EINVAL;
 863
 864         *mask_ret = crypto_algt_inherited_mask(algt);
 865         return 0;
 866 }
 867 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
 868
 869 const char *crypto_attr_alg_name(struct rtattr *rta)
 870 {
 871         struct crypto_attr_alg *alga;
 872
 873         if (!rta)
 874                 return ERR_PTR(-ENOENT);
 875         if (RTA_PAYLOAD(rta) < sizeof(*alga))
 876                 return ERR_PTR(-EINVAL);
 877         if (rta->rta_type != CRYPTOA_ALG)
 878                 return ERR_PTR(-EINVAL);
 879
 880         alga = RTA_DATA(rta);
 881         alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
 882
 883         return alga->name;
 884 }
 885 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
 886
 887 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
 888                         struct crypto_alg *alg)
 889 {
 890         if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
 891                      alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
 892                 return -ENAMETOOLONG;
 893
 894         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
 895                      name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 896                 return -ENAMETOOLONG;
 897
 898         return 0;
 899 }
 900 EXPORT_SYMBOL_GPL(crypto_inst_setname);
 901
 902 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
 903 {
 904         INIT_LIST_HEAD(&queue->list);
 905         queue->backlog = &queue->list;
 906         queue->qlen = 0;
 907         queue->max_qlen = max_qlen;
 908 }
 909 EXPORT_SYMBOL_GPL(crypto_init_queue);
 910
 911 int crypto_enqueue_request(struct crypto_queue *queue,
 912                            struct crypto_async_request *request)
 913 {
 914         int err = -EINPROGRESS;
 915
 916         if (unlikely(queue->qlen >= queue->max_qlen)) {
 917                 if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
 918                         err = -ENOSPC;
 919                         goto out;
 920                 }
 921                 err = -EBUSY;
 922                 if (queue->backlog == &queue->list)
 923                         queue->backlog = &request->list;
 924         }
 925
 926         queue->qlen++;
 927         list_add_tail(&request->list, &queue->list);
 928
 929 out:
 930         return err;
 931 }
 932 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
 933
 934 void crypto_enqueue_request_head(struct crypto_queue *queue,
 935                                  struct crypto_async_request *request)
 936 {
 937         if (unlikely(queue->qlen >= queue->max_qlen))
 938                 queue->backlog = queue->backlog->prev;
 939
 940         queue->qlen++;
 941         list_add(&request->list, &queue->list);
 942 }
 943 EXPORT_SYMBOL_GPL(crypto_enqueue_request_head);
 944
 945 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
 946 {
 947         struct list_head *request;
 948
 949         if (unlikely(!queue->qlen))
 950                 return NULL;
 951
 952         queue->qlen--;
 953
 954         if (queue->backlog != &queue->list)
 955                 queue->backlog = queue->backlog->next;
 956
 957         request = queue->list.next;
 958         list_del(request);
 959
 960         return list_entry(request, struct crypto_async_request, list);
 961 }
 962 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
 963
 964 static inline void crypto_inc_byte(u8 *a, unsigned int size)
 965 {
 966         u8 *b = (a + size);
 967         u8 c;
 968
 969         for (; size; size--) {
 970                 c = *--b + 1;
 971                 *b = c;
 972                 if (c)
 973                         break;
 974         }
 975 }
 976
 977 void crypto_inc(u8 *a, unsigned int size)
 978 {
 979         __be32 *b = (__be32 *)(a + size);
 980         u32 c;
 981
 982         if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
 983             IS_ALIGNED((unsigned long)b, __alignof__(*b)))
 984                 for (; size >= 4; size -= 4) {
 985                         c = be32_to_cpu(*--b) + 1;
 986                         *b = cpu_to_be32(c);
 987                         if (likely(c))
 988                                 return;
 989                 }
 990
 991         crypto_inc_byte(a, size);
 992 }
 993 EXPORT_SYMBOL_GPL(crypto_inc);
 994
 995 unsigned int crypto_alg_extsize(struct crypto_alg *alg)
 996 {
 997         return alg->cra_ctxsize +
 998                (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
 999 }
1000 EXPORT_SYMBOL_GPL(crypto_alg_extsize);
1001
1002 int crypto_type_has_alg(const char *name, const struct crypto_type *frontend,
1003                         u32 type, u32 mask)
1004 {
1005         int ret = 0;
1006         struct crypto_alg *alg = crypto_find_alg(name, frontend, type, mask);
1007
1008         if (!IS_ERR(alg)) {
1009                 crypto_mod_put(alg);
1010                 ret = 1;
1011         }
1012
1013         return ret;
1014 }
1015 EXPORT_SYMBOL_GPL(crypto_type_has_alg);
1016
1017 static void __init crypto_start_tests(void)
1018 {
1019         if (!IS_BUILTIN(CONFIG_CRYPTO_ALGAPI))
1020                 return;
1021
1022         if (IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS))
1023                 return;
1024
1025         for (;;) {
1026                 struct crypto_larval *larval = NULL;
1027                 struct crypto_alg *q;
1028
1029                 down_write(&crypto_alg_sem);
1030
1031                 list_for_each_entry(q, &crypto_alg_list, cra_list) {
1032                         struct crypto_larval *l;
1033
1034                         if (!crypto_is_larval(q))
1035                                 continue;
1036
1037                         l = (void *)q;
1038
1039                         if (!crypto_is_test_larval(l))
1040                                 continue;
1041
1042                         if (l->test_started)
1043                                 continue;
1044
1045                         l->test_started = true;
1046                         larval = l;
1047                         crypto_schedule_test(larval);
1048                         break;
1049                 }
1050
1051                 up_write(&crypto_alg_sem);
1052
1053                 if (!larval)
1054                         break;
1055         }
1056
1057         set_crypto_boot_test_finished();
1058 }
1059
1060 static int __init crypto_algapi_init(void)
1061 {
1062         crypto_init_proc();
1063         crypto_start_tests();
1064         return 0;
1065 }
1066
1067 static void __exit crypto_algapi_exit(void)
1068 {
1069         crypto_exit_proc();
1070 }
1071
1072 /*
1073  * We run this at late_initcall so that all the built-in algorithms
1074  * have had a chance to register themselves first.
1075  */
1076 late_initcall(crypto_algapi_init);
1077 module_exit(crypto_algapi_exit);
1078
1079 MODULE_LICENSE("GPL");
1080 MODULE_DESCRIPTION("Cryptographic algorithms API");
1081 MODULE_SOFTDEP("pre: cryptomgr");