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 <linux/err.h>
  10 #include <linux/errno.h>
  11 #include <linux/fips.h>
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/list.h>
  15 #include <linux/module.h>
  16 #include <linux/rtnetlink.h>
  17 #include <linux/slab.h>
  18 #include <linux/string.h>
  19
  20 #include "internal.h"
  21
  22 static LIST_HEAD(crypto_template_list);
  23
  24 static inline void crypto_check_module_sig(struct module *mod)
  25 {
  26         if (fips_enabled && mod && !module_sig_ok(mod))
  27                 panic("Module %s signature verification failed in FIPS mode\n",
  28                       module_name(mod));
  29 }
  30
  31 static int crypto_check_alg(struct crypto_alg *alg)
  32 {
  33         crypto_check_module_sig(alg->cra_module);
  34
  35         if (!alg->cra_name[0] || !alg->cra_driver_name[0])
  36                 return -EINVAL;
  37
  38         if (alg->cra_alignmask & (alg->cra_alignmask + 1))
  39                 return -EINVAL;
  40
  41         /* General maximums for all algs. */
  42         if (alg->cra_alignmask > MAX_ALGAPI_ALIGNMASK)
  43                 return -EINVAL;
  44
  45         if (alg->cra_blocksize > MAX_ALGAPI_BLOCKSIZE)
  46                 return -EINVAL;
  47
  48         /* Lower maximums for specific alg types. */
  49         if (!alg->cra_type && (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
  50                                CRYPTO_ALG_TYPE_CIPHER) {
  51                 if (alg->cra_alignmask > MAX_CIPHER_ALIGNMASK)
  52                         return -EINVAL;
  53
  54                 if (alg->cra_blocksize > MAX_CIPHER_BLOCKSIZE)
  55                         return -EINVAL;
  56         }
  57
  58         if (alg->cra_priority < 0)
  59                 return -EINVAL;
  60
  61         refcount_set(&alg->cra_refcnt, 1);
  62
  63         return 0;
  64 }
  65
  66 static void crypto_free_instance(struct crypto_instance *inst)
  67 {
  68         inst->alg.cra_type->free(inst);
  69 }
  70
  71 static void crypto_destroy_instance(struct crypto_alg *alg)
  72 {
  73         struct crypto_instance *inst = (void *)alg;
  74         struct crypto_template *tmpl = inst->tmpl;
  75
  76         crypto_free_instance(inst);
  77         crypto_tmpl_put(tmpl);
  78 }
  79
  80 /*
  81  * This function adds a spawn to the list secondary_spawns which
  82  * will be used at the end of crypto_remove_spawns to unregister
  83  * instances, unless the spawn happens to be one that is depended
  84  * on by the new algorithm (nalg in crypto_remove_spawns).
  85  *
  86  * This function is also responsible for resurrecting any algorithms
  87  * in the dependency chain of nalg by unsetting n->dead.
  88  */
  89 static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
  90                                             struct list_head *stack,
  91                                             struct list_head *top,
  92                                             struct list_head *secondary_spawns)
  93 {
  94         struct crypto_spawn *spawn, *n;
  95
  96         spawn = list_first_entry_or_null(stack, struct crypto_spawn, list);
  97         if (!spawn)
  98                 return NULL;
  99
 100         n = list_prev_entry(spawn, list);
 101         list_move(&spawn->list, secondary_spawns);
 102
 103         if (list_is_last(&n->list, stack))
 104                 return top;
 105
 106         n = list_next_entry(n, list);
 107         if (!spawn->dead)
 108                 n->dead = false;
 109
 110         return &n->inst->alg.cra_users;
 111 }
 112
 113 static void crypto_remove_instance(struct crypto_instance *inst,
 114                                    struct list_head *list)
 115 {
 116         struct crypto_template *tmpl = inst->tmpl;
 117
 118         if (crypto_is_dead(&inst->alg))
 119                 return;
 120
 121         inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
 122
 123         if (!tmpl || !crypto_tmpl_get(tmpl))
 124                 return;
 125
 126         list_move(&inst->alg.cra_list, list);
 127         hlist_del(&inst->list);
 128         inst->alg.cra_destroy = crypto_destroy_instance;
 129
 130         BUG_ON(!list_empty(&inst->alg.cra_users));
 131 }
 132
 133 /*
 134  * Given an algorithm alg, remove all algorithms that depend on it
 135  * through spawns.  If nalg is not null, then exempt any algorithms
 136  * that is depended on by nalg.  This is useful when nalg itself
 137  * depends on alg.
 138  */
 139 void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
 140                           struct crypto_alg *nalg)
 141 {
 142         u32 new_type = (nalg ?: alg)->cra_flags;
 143         struct crypto_spawn *spawn, *n;
 144         LIST_HEAD(secondary_spawns);
 145         struct list_head *spawns;
 146         LIST_HEAD(stack);
 147         LIST_HEAD(top);
 148
 149         spawns = &alg->cra_users;
 150         list_for_each_entry_safe(spawn, n, spawns, list) {
 151                 if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
 152                         continue;
 153
 154                 list_move(&spawn->list, &top);
 155         }
 156
 157         /*
 158          * Perform a depth-first walk starting from alg through
 159          * the cra_users tree.  The list stack records the path
 160          * from alg to the current spawn.
 161          */
 162         spawns = &top;
 163         do {
 164                 while (!list_empty(spawns)) {
 165                         struct crypto_instance *inst;
 166
 167                         spawn = list_first_entry(spawns, struct crypto_spawn,
 168                                                  list);
 169                         inst = spawn->inst;
 170
 171                         list_move(&spawn->list, &stack);
 172                         spawn->dead = !spawn->registered || &inst->alg != nalg;
 173
 174                         if (!spawn->registered)
 175                                 break;
 176
 177                         BUG_ON(&inst->alg == alg);
 178
 179                         if (&inst->alg == nalg)
 180                                 break;
 181
 182                         spawns = &inst->alg.cra_users;
 183
 184                         /*
 185                          * Even if spawn->registered is true, the
 186                          * instance itself may still be unregistered.
 187                          * This is because it may have failed during
 188                          * registration.  Therefore we still need to
 189                          * make the following test.
 190                          *
 191                          * We may encounter an unregistered instance here, since
 192                          * an instance's spawns are set up prior to the instance
 193                          * being registered.  An unregistered instance will have
 194                          * NULL ->cra_users.next, since ->cra_users isn't
 195                          * properly initialized until registration.  But an
 196                          * unregistered instance cannot have any users, so treat
 197                          * it the same as ->cra_users being empty.
 198                          */
 199                         if (spawns->next == NULL)
 200                                 break;
 201                 }
 202         } while ((spawns = crypto_more_spawns(alg, &stack, &top,
 203                                               &secondary_spawns)));
 204
 205         /*
 206          * Remove all instances that are marked as dead.  Also
 207          * complete the resurrection of the others by moving them
 208          * back to the cra_users list.
 209          */
 210         list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
 211                 if (!spawn->dead)
 212                         list_move(&spawn->list, &spawn->alg->cra_users);
 213                 else if (spawn->registered)
 214                         crypto_remove_instance(spawn->inst, list);
 215         }
 216 }
 217 EXPORT_SYMBOL_GPL(crypto_remove_spawns);
 218
 219 static struct crypto_larval *crypto_alloc_test_larval(struct crypto_alg *alg)
 220 {
 221         struct crypto_larval *larval;
 222
 223         if (!IS_ENABLED(CONFIG_CRYPTO_MANAGER))
 224                 return NULL;
 225
 226         larval = crypto_larval_alloc(alg->cra_name,
 227                                      alg->cra_flags | CRYPTO_ALG_TESTED, 0);
 228         if (IS_ERR(larval))
 229                 return larval;
 230
 231         larval->adult = crypto_mod_get(alg);
 232         if (!larval->adult) {
 233                 kfree(larval);
 234                 return ERR_PTR(-ENOENT);
 235         }
 236
 237         refcount_set(&larval->alg.cra_refcnt, 1);
 238         memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
 239                CRYPTO_MAX_ALG_NAME);
 240         larval->alg.cra_priority = alg->cra_priority;
 241
 242         return larval;
 243 }
 244
 245 static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)
 246 {
 247         struct crypto_alg *q;
 248         struct crypto_larval *larval;
 249         int ret = -EAGAIN;
 250
 251         if (crypto_is_dead(alg))
 252                 goto err;
 253
 254         INIT_LIST_HEAD(&alg->cra_users);
 255
 256         /* No cheating! */
 257         alg->cra_flags &= ~CRYPTO_ALG_TESTED;
 258
 259         ret = -EEXIST;
 260
 261         list_for_each_entry(q, &crypto_alg_list, cra_list) {
 262                 if (q == alg)
 263                         goto err;
 264
 265                 if (crypto_is_moribund(q))
 266                         continue;
 267
 268                 if (crypto_is_larval(q)) {
 269                         if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
 270                                 goto err;
 271                         continue;
 272                 }
 273
 274                 if (!strcmp(q->cra_driver_name, alg->cra_name) ||
 275                     !strcmp(q->cra_name, alg->cra_driver_name))
 276                         goto err;
 277         }
 278
 279         larval = crypto_alloc_test_larval(alg);
 280         if (IS_ERR(larval))
 281                 goto out;
 282
 283         list_add(&alg->cra_list, &crypto_alg_list);
 284
 285         if (larval)
 286                 list_add(&larval->alg.cra_list, &crypto_alg_list);
 287
 288         crypto_stats_init(alg);
 289
 290 out:
 291         return larval;
 292
 293 err:
 294         larval = ERR_PTR(ret);
 295         goto out;
 296 }
 297
 298 void crypto_alg_tested(const char *name, int err)
 299 {
 300         struct crypto_larval *test;
 301         struct crypto_alg *alg;
 302         struct crypto_alg *q;
 303         LIST_HEAD(list);
 304         bool best;
 305
 306         down_write(&crypto_alg_sem);
 307         list_for_each_entry(q, &crypto_alg_list, cra_list) {
 308                 if (crypto_is_moribund(q) || !crypto_is_larval(q))
 309                         continue;
 310
 311                 test = (struct crypto_larval *)q;
 312
 313                 if (!strcmp(q->cra_driver_name, name))
 314                         goto found;
 315         }
 316
 317         pr_err("alg: Unexpected test result for %s: %d\n", name, err);
 318         goto unlock;
 319
 320 found:
 321         q->cra_flags |= CRYPTO_ALG_DEAD;
 322         alg = test->adult;
 323         if (err || list_empty(&alg->cra_list))
 324                 goto complete;
 325
 326         alg->cra_flags |= CRYPTO_ALG_TESTED;
 327
 328         /* Only satisfy larval waiters if we are the best. */
 329         best = true;
 330         list_for_each_entry(q, &crypto_alg_list, cra_list) {
 331                 if (crypto_is_moribund(q) || !crypto_is_larval(q))
 332                         continue;
 333
 334                 if (strcmp(alg->cra_name, q->cra_name))
 335                         continue;
 336
 337                 if (q->cra_priority > alg->cra_priority) {
 338                         best = false;
 339                         break;
 340                 }
 341         }
 342
 343         list_for_each_entry(q, &crypto_alg_list, cra_list) {
 344                 if (q == alg)
 345                         continue;
 346
 347                 if (crypto_is_moribund(q))
 348                         continue;
 349
 350                 if (crypto_is_larval(q)) {
 351                         struct crypto_larval *larval = (void *)q;
 352
 353                         /*
 354                          * Check to see if either our generic name or
 355                          * specific name can satisfy the name requested
 356                          * by the larval entry q.
 357                          */
 358                         if (strcmp(alg->cra_name, q->cra_name) &&
 359                             strcmp(alg->cra_driver_name, q->cra_name))
 360                                 continue;
 361
 362                         if (larval->adult)
 363                                 continue;
 364                         if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
 365                                 continue;
 366
 367                         if (best && crypto_mod_get(alg))
 368                                 larval->adult = alg;
 369                         else
 370                                 larval->adult = ERR_PTR(-EAGAIN);
 371
 372                         continue;
 373                 }
 374
 375                 if (strcmp(alg->cra_name, q->cra_name))
 376                         continue;
 377
 378                 if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
 379                     q->cra_priority > alg->cra_priority)
 380                         continue;
 381
 382                 crypto_remove_spawns(q, &list, alg);
 383         }
 384
 385 complete:
 386         complete_all(&test->completion);
 387
 388 unlock:
 389         up_write(&crypto_alg_sem);
 390
 391         crypto_remove_final(&list);
 392 }
 393 EXPORT_SYMBOL_GPL(crypto_alg_tested);
 394
 395 void crypto_remove_final(struct list_head *list)
 396 {
 397         struct crypto_alg *alg;
 398         struct crypto_alg *n;
 399
 400         list_for_each_entry_safe(alg, n, list, cra_list) {
 401                 list_del_init(&alg->cra_list);
 402                 crypto_alg_put(alg);
 403         }
 404 }
 405 EXPORT_SYMBOL_GPL(crypto_remove_final);
 406
 407 int crypto_register_alg(struct crypto_alg *alg)
 408 {
 409         struct crypto_larval *larval;
 410         bool test_started;
 411         int err;
 412
 413         alg->cra_flags &= ~CRYPTO_ALG_DEAD;
 414         err = crypto_check_alg(alg);
 415         if (err)
 416                 return err;
 417
 418         down_write(&crypto_alg_sem);
 419         larval = __crypto_register_alg(alg);
 420         test_started = static_key_enabled(&crypto_boot_test_finished);
 421         if (!IS_ERR_OR_NULL(larval))
 422                 larval->test_started = test_started;
 423         up_write(&crypto_alg_sem);
 424
 425         if (IS_ERR_OR_NULL(larval))
 426                 return PTR_ERR(larval);
 427
 428         if (test_started)
 429                 crypto_wait_for_test(larval);
 430         return 0;
 431 }
 432 EXPORT_SYMBOL_GPL(crypto_register_alg);
 433
 434 static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
 435 {
 436         if (unlikely(list_empty(&alg->cra_list)))
 437                 return -ENOENT;
 438
 439         alg->cra_flags |= CRYPTO_ALG_DEAD;
 440
 441         list_del_init(&alg->cra_list);
 442         crypto_remove_spawns(alg, list, NULL);
 443
 444         return 0;
 445 }
 446
 447 void crypto_unregister_alg(struct crypto_alg *alg)
 448 {
 449         int ret;
 450         LIST_HEAD(list);
 451
 452         down_write(&crypto_alg_sem);
 453         ret = crypto_remove_alg(alg, &list);
 454         up_write(&crypto_alg_sem);
 455
 456         if (WARN(ret, "Algorithm %s is not registered", alg->cra_driver_name))
 457                 return;
 458
 459         BUG_ON(refcount_read(&alg->cra_refcnt) != 1);
 460         if (alg->cra_destroy)
 461                 alg->cra_destroy(alg);
 462
 463         crypto_remove_final(&list);
 464 }
 465 EXPORT_SYMBOL_GPL(crypto_unregister_alg);
 466
 467 int crypto_register_algs(struct crypto_alg *algs, int count)
 468 {
 469         int i, ret;
 470
 471         for (i = 0; i < count; i++) {
 472                 ret = crypto_register_alg(&algs[i]);
 473                 if (ret)
 474                         goto err;
 475         }
 476
 477         return 0;
 478
 479 err:
 480         for (--i; i >= 0; --i)
 481                 crypto_unregister_alg(&algs[i]);
 482
 483         return ret;
 484 }
 485 EXPORT_SYMBOL_GPL(crypto_register_algs);
 486
 487 void crypto_unregister_algs(struct crypto_alg *algs, int count)
 488 {
 489         int i;
 490
 491         for (i = 0; i < count; i++)
 492                 crypto_unregister_alg(&algs[i]);
 493 }
 494 EXPORT_SYMBOL_GPL(crypto_unregister_algs);
 495
 496 int crypto_register_template(struct crypto_template *tmpl)
 497 {
 498         struct crypto_template *q;
 499         int err = -EEXIST;
 500
 501         down_write(&crypto_alg_sem);
 502
 503         crypto_check_module_sig(tmpl->module);
 504
 505         list_for_each_entry(q, &crypto_template_list, list) {
 506                 if (q == tmpl)
 507                         goto out;
 508         }
 509
 510         list_add(&tmpl->list, &crypto_template_list);
 511         err = 0;
 512 out:
 513         up_write(&crypto_alg_sem);
 514         return err;
 515 }
 516 EXPORT_SYMBOL_GPL(crypto_register_template);
 517
 518 int crypto_register_templates(struct crypto_template *tmpls, int count)
 519 {
 520         int i, err;
 521
 522         for (i = 0; i < count; i++) {
 523                 err = crypto_register_template(&tmpls[i]);
 524                 if (err)
 525                         goto out;
 526         }
 527         return 0;
 528
 529 out:
 530         for (--i; i >= 0; --i)
 531                 crypto_unregister_template(&tmpls[i]);
 532         return err;
 533 }
 534 EXPORT_SYMBOL_GPL(crypto_register_templates);
 535
 536 void crypto_unregister_template(struct crypto_template *tmpl)
 537 {
 538         struct crypto_instance *inst;
 539         struct hlist_node *n;
 540         struct hlist_head *list;
 541         LIST_HEAD(users);
 542
 543         down_write(&crypto_alg_sem);
 544
 545         BUG_ON(list_empty(&tmpl->list));
 546         list_del_init(&tmpl->list);
 547
 548         list = &tmpl->instances;
 549         hlist_for_each_entry(inst, list, list) {
 550                 int err = crypto_remove_alg(&inst->alg, &users);
 551
 552                 BUG_ON(err);
 553         }
 554
 555         up_write(&crypto_alg_sem);
 556
 557         hlist_for_each_entry_safe(inst, n, list, list) {
 558                 BUG_ON(refcount_read(&inst->alg.cra_refcnt) != 1);
 559                 crypto_free_instance(inst);
 560         }
 561         crypto_remove_final(&users);
 562 }
 563 EXPORT_SYMBOL_GPL(crypto_unregister_template);
 564
 565 void crypto_unregister_templates(struct crypto_template *tmpls, int count)
 566 {
 567         int i;
 568
 569         for (i = count - 1; i >= 0; --i)
 570                 crypto_unregister_template(&tmpls[i]);
 571 }
 572 EXPORT_SYMBOL_GPL(crypto_unregister_templates);
 573
 574 static struct crypto_template *__crypto_lookup_template(const char *name)
 575 {
 576         struct crypto_template *q, *tmpl = NULL;
 577
 578         down_read(&crypto_alg_sem);
 579         list_for_each_entry(q, &crypto_template_list, list) {
 580                 if (strcmp(q->name, name))
 581                         continue;
 582                 if (unlikely(!crypto_tmpl_get(q)))
 583                         continue;
 584
 585                 tmpl = q;
 586                 break;
 587         }
 588         up_read(&crypto_alg_sem);
 589
 590         return tmpl;
 591 }
 592
 593 struct crypto_template *crypto_lookup_template(const char *name)
 594 {
 595         return try_then_request_module(__crypto_lookup_template(name),
 596                                        "crypto-%s", name);
 597 }
 598 EXPORT_SYMBOL_GPL(crypto_lookup_template);
 599
 600 int crypto_register_instance(struct crypto_template *tmpl,
 601                              struct crypto_instance *inst)
 602 {
 603         struct crypto_larval *larval;
 604         struct crypto_spawn *spawn;
 605         int err;
 606
 607         err = crypto_check_alg(&inst->alg);
 608         if (err)
 609                 return err;
 610
 611         inst->alg.cra_module = tmpl->module;
 612         inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
 613
 614         down_write(&crypto_alg_sem);
 615
 616         larval = ERR_PTR(-EAGAIN);
 617         for (spawn = inst->spawns; spawn;) {
 618                 struct crypto_spawn *next;
 619
 620                 if (spawn->dead)
 621                         goto unlock;
 622
 623                 next = spawn->next;
 624                 spawn->inst = inst;
 625                 spawn->registered = true;
 626
 627                 crypto_mod_put(spawn->alg);
 628
 629                 spawn = next;
 630         }
 631
 632         larval = __crypto_register_alg(&inst->alg);
 633         if (IS_ERR(larval))
 634                 goto unlock;
 635         else if (larval)
 636                 larval->test_started = true;
 637
 638         hlist_add_head(&inst->list, &tmpl->instances);
 639         inst->tmpl = tmpl;
 640
 641 unlock:
 642         up_write(&crypto_alg_sem);
 643
 644         err = PTR_ERR(larval);
 645         if (IS_ERR_OR_NULL(larval))
 646                 goto err;
 647
 648         crypto_wait_for_test(larval);
 649         err = 0;
 650
 651 err:
 652         return err;
 653 }
 654 EXPORT_SYMBOL_GPL(crypto_register_instance);
 655
 656 void crypto_unregister_instance(struct crypto_instance *inst)
 657 {
 658         LIST_HEAD(list);
 659
 660         down_write(&crypto_alg_sem);
 661
 662         crypto_remove_spawns(&inst->alg, &list, NULL);
 663         crypto_remove_instance(inst, &list);
 664
 665         up_write(&crypto_alg_sem);
 666
 667         crypto_remove_final(&list);
 668 }
 669 EXPORT_SYMBOL_GPL(crypto_unregister_instance);
 670
 671 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
 672                       const char *name, u32 type, u32 mask)
 673 {
 674         struct crypto_alg *alg;
 675         int err = -EAGAIN;
 676
 677         if (WARN_ON_ONCE(inst == NULL))
 678                 return -EINVAL;
 679
 680         /* Allow the result of crypto_attr_alg_name() to be passed directly */
 681         if (IS_ERR(name))
 682                 return PTR_ERR(name);
 683
 684         alg = crypto_find_alg(name, spawn->frontend, type, mask);
 685         if (IS_ERR(alg))
 686                 return PTR_ERR(alg);
 687
 688         down_write(&crypto_alg_sem);
 689         if (!crypto_is_moribund(alg)) {
 690                 list_add(&spawn->list, &alg->cra_users);
 691                 spawn->alg = alg;
 692                 spawn->mask = mask;
 693                 spawn->next = inst->spawns;
 694                 inst->spawns = spawn;
 695                 inst->alg.cra_flags |=
 696                         (alg->cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
 697                 err = 0;
 698         }
 699         up_write(&crypto_alg_sem);
 700         if (err)
 701                 crypto_mod_put(alg);
 702         return err;
 703 }
 704 EXPORT_SYMBOL_GPL(crypto_grab_spawn);
 705
 706 void crypto_drop_spawn(struct crypto_spawn *spawn)
 707 {
 708         if (!spawn->alg) /* not yet initialized? */
 709                 return;
 710
 711         down_write(&crypto_alg_sem);
 712         if (!spawn->dead)
 713                 list_del(&spawn->list);
 714         up_write(&crypto_alg_sem);
 715
 716         if (!spawn->registered)
 717                 crypto_mod_put(spawn->alg);
 718 }
 719 EXPORT_SYMBOL_GPL(crypto_drop_spawn);
 720
 721 static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
 722 {
 723         struct crypto_alg *alg = ERR_PTR(-EAGAIN);
 724         struct crypto_alg *target;
 725         bool shoot = false;
 726
 727         down_read(&crypto_alg_sem);
 728         if (!spawn->dead) {
 729                 alg = spawn->alg;
 730                 if (!crypto_mod_get(alg)) {
 731                         target = crypto_alg_get(alg);
 732                         shoot = true;
 733                         alg = ERR_PTR(-EAGAIN);
 734                 }
 735         }
 736         up_read(&crypto_alg_sem);
 737
 738         if (shoot) {
 739                 crypto_shoot_alg(target);
 740                 crypto_alg_put(target);
 741         }
 742
 743         return alg;
 744 }
 745
 746 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
 747                                     u32 mask)
 748 {
 749         struct crypto_alg *alg;
 750         struct crypto_tfm *tfm;
 751
 752         alg = crypto_spawn_alg(spawn);
 753         if (IS_ERR(alg))
 754                 return ERR_CAST(alg);
 755
 756         tfm = ERR_PTR(-EINVAL);
 757         if (unlikely((alg->cra_flags ^ type) & mask))
 758                 goto out_put_alg;
 759
 760         tfm = __crypto_alloc_tfm(alg, type, mask);
 761         if (IS_ERR(tfm))
 762                 goto out_put_alg;
 763
 764         return tfm;
 765
 766 out_put_alg:
 767         crypto_mod_put(alg);
 768         return tfm;
 769 }
 770 EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
 771
 772 void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
 773 {
 774         struct crypto_alg *alg;
 775         struct crypto_tfm *tfm;
 776
 777         alg = crypto_spawn_alg(spawn);
 778         if (IS_ERR(alg))
 779                 return ERR_CAST(alg);
 780
 781         tfm = crypto_create_tfm(alg, spawn->frontend);
 782         if (IS_ERR(tfm))
 783                 goto out_put_alg;
 784
 785         return tfm;
 786
 787 out_put_alg:
 788         crypto_mod_put(alg);
 789         return tfm;
 790 }
 791 EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
 792
 793 int crypto_register_notifier(struct notifier_block *nb)
 794 {
 795         return blocking_notifier_chain_register(&crypto_chain, nb);
 796 }
 797 EXPORT_SYMBOL_GPL(crypto_register_notifier);
 798
 799 int crypto_unregister_notifier(struct notifier_block *nb)
 800 {
 801         return blocking_notifier_chain_unregister(&crypto_chain, nb);
 802 }
 803 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
 804
 805 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
 806 {
 807         struct rtattr *rta = tb[0];
 808         struct crypto_attr_type *algt;
 809
 810         if (!rta)
 811                 return ERR_PTR(-ENOENT);
 812         if (RTA_PAYLOAD(rta) < sizeof(*algt))
 813                 return ERR_PTR(-EINVAL);
 814         if (rta->rta_type != CRYPTOA_TYPE)
 815                 return ERR_PTR(-EINVAL);
 816
 817         algt = RTA_DATA(rta);
 818
 819         return algt;
 820 }
 821 EXPORT_SYMBOL_GPL(crypto_get_attr_type);
 822
 823 /**
 824  * crypto_check_attr_type() - check algorithm type and compute inherited mask
 825  * @tb: the template parameters
 826  * @type: the algorithm type the template would be instantiated as
 827  * @mask_ret: (output) the mask that should be passed to crypto_grab_*()
 828  *            to restrict the flags of any inner algorithms
 829  *
 830  * Validate that the algorithm type the user requested is compatible with the
 831  * one the template would actually be instantiated as.  E.g., if the user is
 832  * doing crypto_alloc_shash("cbc(aes)", ...), this would return an error because
 833  * the "cbc" template creates an "skcipher" algorithm, not an "shash" algorithm.
 834  *
 835  * Also compute the mask to use to restrict the flags of any inner algorithms.
 836  *
 837  * Return: 0 on success; -errno on failure
 838  */
 839 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret)
 840 {
 841         struct crypto_attr_type *algt;
 842
 843         algt = crypto_get_attr_type(tb);
 844         if (IS_ERR(algt))
 845                 return PTR_ERR(algt);
 846
 847         if ((algt->type ^ type) & algt->mask)
 848                 return -EINVAL;
 849
 850         *mask_ret = crypto_algt_inherited_mask(algt);
 851         return 0;
 852 }
 853 EXPORT_SYMBOL_GPL(crypto_check_attr_type);
 854
 855 const char *crypto_attr_alg_name(struct rtattr *rta)
 856 {
 857         struct crypto_attr_alg *alga;
 858
 859         if (!rta)
 860                 return ERR_PTR(-ENOENT);
 861         if (RTA_PAYLOAD(rta) < sizeof(*alga))
 862                 return ERR_PTR(-EINVAL);
 863         if (rta->rta_type != CRYPTOA_ALG)
 864                 return ERR_PTR(-EINVAL);
 865
 866         alga = RTA_DATA(rta);
 867         alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
 868
 869         return alga->name;
 870 }
 871 EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
 872
 873 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
 874                         struct crypto_alg *alg)
 875 {
 876         if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
 877                      alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
 878                 return -ENAMETOOLONG;
 879
 880         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
 881                      name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 882                 return -ENAMETOOLONG;
 883
 884         return 0;
 885 }
 886 EXPORT_SYMBOL_GPL(crypto_inst_setname);
 887
 888 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
 889 {
 890         INIT_LIST_HEAD(&queue->list);
 891         queue->backlog = &queue->list;
 892         queue->qlen = 0;
 893         queue->max_qlen = max_qlen;
 894 }
 895 EXPORT_SYMBOL_GPL(crypto_init_queue);
 896
 897 int crypto_enqueue_request(struct crypto_queue *queue,
 898                            struct crypto_async_request *request)
 899 {
 900         int err = -EINPROGRESS;
 901
 902         if (unlikely(queue->qlen >= queue->max_qlen)) {
 903                 if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
 904                         err = -ENOSPC;
 905                         goto out;
 906                 }
 907                 err = -EBUSY;
 908                 if (queue->backlog == &queue->list)
 909                         queue->backlog = &request->list;
 910         }
 911
 912         queue->qlen++;
 913         list_add_tail(&request->list, &queue->list);
 914
 915 out:
 916         return err;
 917 }
 918 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
 919
 920 void crypto_enqueue_request_head(struct crypto_queue *queue,
 921                                  struct crypto_async_request *request)
 922 {
 923         queue->qlen++;
 924         list_add(&request->list, &queue->list);
 925 }
 926 EXPORT_SYMBOL_GPL(crypto_enqueue_request_head);
 927
 928 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
 929 {
 930         struct list_head *request;
 931
 932         if (unlikely(!queue->qlen))
 933                 return NULL;
 934
 935         queue->qlen--;
 936
 937         if (queue->backlog != &queue->list)
 938                 queue->backlog = queue->backlog->next;
 939
 940         request = queue->list.next;
 941         list_del(request);
 942
 943         return list_entry(request, struct crypto_async_request, list);
 944 }
 945 EXPORT_SYMBOL_GPL(crypto_dequeue_request);
 946
 947 static inline void crypto_inc_byte(u8 *a, unsigned int size)
 948 {
 949         u8 *b = (a + size);
 950         u8 c;
 951
 952         for (; size; size--) {
 953                 c = *--b + 1;
 954                 *b = c;
 955                 if (c)
 956                         break;
 957         }
 958 }
 959
 960 void crypto_inc(u8 *a, unsigned int size)
 961 {
 962         __be32 *b = (__be32 *)(a + size);
 963         u32 c;
 964
 965         if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
 966             IS_ALIGNED((unsigned long)b, __alignof__(*b)))
 967                 for (; size >= 4; size -= 4) {
 968                         c = be32_to_cpu(*--b) + 1;
 969                         *b = cpu_to_be32(c);
 970                         if (likely(c))
 971                                 return;
 972                 }
 973
 974         crypto_inc_byte(a, size);
 975 }
 976 EXPORT_SYMBOL_GPL(crypto_inc);
 977
 978 void __crypto_xor(u8 *dst, const u8 *src1, const u8 *src2, unsigned int len)
 979 {
 980         int relalign = 0;
 981
 982         if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) {
 983                 int size = sizeof(unsigned long);
 984                 int d = (((unsigned long)dst ^ (unsigned long)src1) |
 985                          ((unsigned long)dst ^ (unsigned long)src2)) &
 986                         (size - 1);
 987
 988                 relalign = d ? 1 << __ffs(d) : size;
 989
 990                 /*
 991                  * If we care about alignment, process as many bytes as
 992                  * needed to advance dst and src to values whose alignments
 993                  * equal their relative alignment. This will allow us to
 994                  * process the remainder of the input using optimal strides.
 995                  */
 996                 while (((unsigned long)dst & (relalign - 1)) && len > 0) {
 997                         *dst++ = *src1++ ^ *src2++;
 998                         len--;
 999                 }
1000         }
1001
1002         while (IS_ENABLED(CONFIG_64BIT) && len >= 8 && !(relalign & 7)) {
1003                 *(u64 *)dst = *(u64 *)src1 ^  *(u64 *)src2;
1004                 dst += 8;
1005                 src1 += 8;
1006                 src2 += 8;
1007                 len -= 8;
1008         }
1009
1010         while (len >= 4 && !(relalign & 3)) {
1011                 *(u32 *)dst = *(u32 *)src1 ^ *(u32 *)src2;
1012                 dst += 4;
1013                 src1 += 4;
1014                 src2 += 4;
1015                 len -= 4;
1016         }
1017
1018         while (len >= 2 && !(relalign & 1)) {
1019                 *(u16 *)dst = *(u16 *)src1 ^ *(u16 *)src2;
1020                 dst += 2;
1021                 src1 += 2;
1022                 src2 += 2;
1023                 len -= 2;
1024         }
1025
1026         while (len--)
1027                 *dst++ = *src1++ ^ *src2++;
1028 }
1029 EXPORT_SYMBOL_GPL(__crypto_xor);
1030
1031 unsigned int crypto_alg_extsize(struct crypto_alg *alg)
1032 {
1033         return alg->cra_ctxsize +
1034                (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
1035 }
1036 EXPORT_SYMBOL_GPL(crypto_alg_extsize);
1037
1038 int crypto_type_has_alg(const char *name, const struct crypto_type *frontend,
1039                         u32 type, u32 mask)
1040 {
1041         int ret = 0;
1042         struct crypto_alg *alg = crypto_find_alg(name, frontend, type, mask);
1043
1044         if (!IS_ERR(alg)) {
1045                 crypto_mod_put(alg);
1046                 ret = 1;
1047         }
1048
1049         return ret;
1050 }
1051 EXPORT_SYMBOL_GPL(crypto_type_has_alg);
1052
1053 #ifdef CONFIG_CRYPTO_STATS
1054 void crypto_stats_init(struct crypto_alg *alg)
1055 {
1056         memset(&alg->stats, 0, sizeof(alg->stats));
1057 }
1058 EXPORT_SYMBOL_GPL(crypto_stats_init);
1059
1060 void crypto_stats_get(struct crypto_alg *alg)
1061 {
1062         crypto_alg_get(alg);
1063 }
1064 EXPORT_SYMBOL_GPL(crypto_stats_get);
1065
1066 void crypto_stats_aead_encrypt(unsigned int cryptlen, struct crypto_alg *alg,
1067                                int ret)
1068 {
1069         if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1070                 atomic64_inc(&alg->stats.aead.err_cnt);
1071         } else {
1072                 atomic64_inc(&alg->stats.aead.encrypt_cnt);
1073                 atomic64_add(cryptlen, &alg->stats.aead.encrypt_tlen);
1074         }
1075         crypto_alg_put(alg);
1076 }
1077 EXPORT_SYMBOL_GPL(crypto_stats_aead_encrypt);
1078
1079 void crypto_stats_aead_decrypt(unsigned int cryptlen, struct crypto_alg *alg,
1080                                int ret)
1081 {
1082         if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1083                 atomic64_inc(&alg->stats.aead.err_cnt);
1084         } else {
1085                 atomic64_inc(&alg->stats.aead.decrypt_cnt);
1086                 atomic64_add(cryptlen, &alg->stats.aead.decrypt_tlen);
1087         }
1088         crypto_alg_put(alg);
1089 }
1090 EXPORT_SYMBOL_GPL(crypto_stats_aead_decrypt);
1091
1092 void crypto_stats_akcipher_encrypt(unsigned int src_len, int ret,
1093                                    struct crypto_alg *alg)
1094 {
1095         if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1096                 atomic64_inc(&alg->stats.akcipher.err_cnt);
1097         } else {
1098                 atomic64_inc(&alg->stats.akcipher.encrypt_cnt);
1099                 atomic64_add(src_len, &alg->stats.akcipher.encrypt_tlen);
1100         }
1101         crypto_alg_put(alg);
1102 }
1103 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_encrypt);
1104
1105 void crypto_stats_akcipher_decrypt(unsigned int src_len, int ret,
1106                                    struct crypto_alg *alg)
1107 {
1108         if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1109                 atomic64_inc(&alg->stats.akcipher.err_cnt);
1110         } else {
1111                 atomic64_inc(&alg->stats.akcipher.decrypt_cnt);
1112                 atomic64_add(src_len, &alg->stats.akcipher.decrypt_tlen);
1113         }
1114         crypto_alg_put(alg);
1115 }
1116 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_decrypt);
1117
1118 void crypto_stats_akcipher_sign(int ret, struct crypto_alg *alg)
1119 {
1120         if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1121                 atomic64_inc(&alg->stats.akcipher.err_cnt);
1122         else
1123                 atomic64_inc(&alg->stats.akcipher.sign_cnt);
1124         crypto_alg_put(alg);
1125 }
1126 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_sign);
1127
1128 void crypto_stats_akcipher_verify(int ret, struct crypto_alg *alg)
1129 {
1130         if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1131                 atomic64_inc(&alg->stats.akcipher.err_cnt);
1132         else
1133                 atomic64_inc(&alg->stats.akcipher.verify_cnt);
1134         crypto_alg_put(alg);
1135 }
1136 EXPORT_SYMBOL_GPL(crypto_stats_akcipher_verify);
1137
1138 void crypto_stats_compress(unsigned int slen, int ret, struct crypto_alg *alg)
1139 {
1140         if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1141                 atomic64_inc(&alg->stats.compress.err_cnt);
1142         } else {
1143                 atomic64_inc(&alg->stats.compress.compress_cnt);
1144                 atomic64_add(slen, &alg->stats.compress.compress_tlen);
1145         }
1146         crypto_alg_put(alg);
1147 }
1148 EXPORT_SYMBOL_GPL(crypto_stats_compress);
1149
1150 void crypto_stats_decompress(unsigned int slen, int ret, struct crypto_alg *alg)
1151 {
1152         if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1153                 atomic64_inc(&alg->stats.compress.err_cnt);
1154         } else {
1155                 atomic64_inc(&alg->stats.compress.decompress_cnt);
1156                 atomic64_add(slen, &alg->stats.compress.decompress_tlen);
1157         }
1158         crypto_alg_put(alg);
1159 }
1160 EXPORT_SYMBOL_GPL(crypto_stats_decompress);
1161
1162 void crypto_stats_ahash_update(unsigned int nbytes, int ret,
1163                                struct crypto_alg *alg)
1164 {
1165         if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1166                 atomic64_inc(&alg->stats.hash.err_cnt);
1167         else
1168                 atomic64_add(nbytes, &alg->stats.hash.hash_tlen);
1169         crypto_alg_put(alg);
1170 }
1171 EXPORT_SYMBOL_GPL(crypto_stats_ahash_update);
1172
1173 void crypto_stats_ahash_final(unsigned int nbytes, int ret,
1174                               struct crypto_alg *alg)
1175 {
1176         if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1177                 atomic64_inc(&alg->stats.hash.err_cnt);
1178         } else {
1179                 atomic64_inc(&alg->stats.hash.hash_cnt);
1180                 atomic64_add(nbytes, &alg->stats.hash.hash_tlen);
1181         }
1182         crypto_alg_put(alg);
1183 }
1184 EXPORT_SYMBOL_GPL(crypto_stats_ahash_final);
1185
1186 void crypto_stats_kpp_set_secret(struct crypto_alg *alg, int ret)
1187 {
1188         if (ret)
1189                 atomic64_inc(&alg->stats.kpp.err_cnt);
1190         else
1191                 atomic64_inc(&alg->stats.kpp.setsecret_cnt);
1192         crypto_alg_put(alg);
1193 }
1194 EXPORT_SYMBOL_GPL(crypto_stats_kpp_set_secret);
1195
1196 void crypto_stats_kpp_generate_public_key(struct crypto_alg *alg, int ret)
1197 {
1198         if (ret)
1199                 atomic64_inc(&alg->stats.kpp.err_cnt);
1200         else
1201                 atomic64_inc(&alg->stats.kpp.generate_public_key_cnt);
1202         crypto_alg_put(alg);
1203 }
1204 EXPORT_SYMBOL_GPL(crypto_stats_kpp_generate_public_key);
1205
1206 void crypto_stats_kpp_compute_shared_secret(struct crypto_alg *alg, int ret)
1207 {
1208         if (ret)
1209                 atomic64_inc(&alg->stats.kpp.err_cnt);
1210         else
1211                 atomic64_inc(&alg->stats.kpp.compute_shared_secret_cnt);
1212         crypto_alg_put(alg);
1213 }
1214 EXPORT_SYMBOL_GPL(crypto_stats_kpp_compute_shared_secret);
1215
1216 void crypto_stats_rng_seed(struct crypto_alg *alg, int ret)
1217 {
1218         if (ret && ret != -EINPROGRESS && ret != -EBUSY)
1219                 atomic64_inc(&alg->stats.rng.err_cnt);
1220         else
1221                 atomic64_inc(&alg->stats.rng.seed_cnt);
1222         crypto_alg_put(alg);
1223 }
1224 EXPORT_SYMBOL_GPL(crypto_stats_rng_seed);
1225
1226 void crypto_stats_rng_generate(struct crypto_alg *alg, unsigned int dlen,
1227                                int ret)
1228 {
1229         if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1230                 atomic64_inc(&alg->stats.rng.err_cnt);
1231         } else {
1232                 atomic64_inc(&alg->stats.rng.generate_cnt);
1233                 atomic64_add(dlen, &alg->stats.rng.generate_tlen);
1234         }
1235         crypto_alg_put(alg);
1236 }
1237 EXPORT_SYMBOL_GPL(crypto_stats_rng_generate);
1238
1239 void crypto_stats_skcipher_encrypt(unsigned int cryptlen, int ret,
1240                                    struct crypto_alg *alg)
1241 {
1242         if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1243                 atomic64_inc(&alg->stats.cipher.err_cnt);
1244         } else {
1245                 atomic64_inc(&alg->stats.cipher.encrypt_cnt);
1246                 atomic64_add(cryptlen, &alg->stats.cipher.encrypt_tlen);
1247         }
1248         crypto_alg_put(alg);
1249 }
1250 EXPORT_SYMBOL_GPL(crypto_stats_skcipher_encrypt);
1251
1252 void crypto_stats_skcipher_decrypt(unsigned int cryptlen, int ret,
1253                                    struct crypto_alg *alg)
1254 {
1255         if (ret && ret != -EINPROGRESS && ret != -EBUSY) {
1256                 atomic64_inc(&alg->stats.cipher.err_cnt);
1257         } else {
1258                 atomic64_inc(&alg->stats.cipher.decrypt_cnt);
1259                 atomic64_add(cryptlen, &alg->stats.cipher.decrypt_tlen);
1260         }
1261         crypto_alg_put(alg);
1262 }
1263 EXPORT_SYMBOL_GPL(crypto_stats_skcipher_decrypt);
1264 #endif
1265
1266 static void __init crypto_start_tests(void)
1267 {
1268         for (;;) {
1269                 struct crypto_larval *larval = NULL;
1270                 struct crypto_alg *q;
1271
1272                 down_write(&crypto_alg_sem);
1273
1274                 list_for_each_entry(q, &crypto_alg_list, cra_list) {
1275                         struct crypto_larval *l;
1276
1277                         if (!crypto_is_larval(q))
1278                                 continue;
1279
1280                         l = (void *)q;
1281
1282                         if (!crypto_is_test_larval(l))
1283                                 continue;
1284
1285                         if (l->test_started)
1286                                 continue;
1287
1288                         l->test_started = true;
1289                         larval = l;
1290                         break;
1291                 }
1292
1293                 up_write(&crypto_alg_sem);
1294
1295                 if (!larval)
1296                         break;
1297
1298                 crypto_wait_for_test(larval);
1299         }
1300
1301         static_branch_enable(&crypto_boot_test_finished);
1302 }
1303
1304 static int __init crypto_algapi_init(void)
1305 {
1306         crypto_init_proc();
1307         crypto_start_tests();
1308         return 0;
1309 }
1310
1311 static void __exit crypto_algapi_exit(void)
1312 {
1313         crypto_exit_proc();
1314 }
1315
1316 /*
1317  * We run this at late_initcall so that all the built-in algorithms
1318  * have had a chance to register themselves first.
1319  */
1320 late_initcall(crypto_algapi_init);
1321 module_exit(crypto_algapi_exit);
1322
1323 MODULE_LICENSE("GPL");
1324 MODULE_DESCRIPTION("Cryptographic algorithms API");