linux/crypto/algapi.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Cryptographic API for algorithms (i.e., low-level API).
   4 *
   5 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
   6 */
   7
   8#include <crypto/algapi.h>
   9#include <crypto/internal/simd.h>
  10#include <linux/err.h>
  11#include <linux/errno.h>
  12#include <linux/fips.h>
  13#include <linux/init.h>
  14#include <linux/kernel.h>
  15#include <linux/list.h>
  16#include <linux/module.h>
  17#include <linux/rtnetlink.h>
  18#include <linux/slab.h>
  19#include <linux/string.h>
  20#include <linux/workqueue.h>
  21
  22#include "internal.h"
  23
  24static LIST_HEAD(crypto_template_list);
  25
  26#ifdef CONFIG_CRYPTO_MANAGER_EXTRA_TESTS
  27DEFINE_PER_CPU(bool, crypto_simd_disabled_for_test);
  28EXPORT_PER_CPU_SYMBOL_GPL(crypto_simd_disabled_for_test);
  29#endif
  30
  31static 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
  38static 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
  73static void crypto_free_instance(struct crypto_instance *inst)
  74{
  75        inst->alg.cra_type->free(inst);
  76}
  77
  78static 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
  88static 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 */
 107static 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
 131static 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 */
 157void 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}
 235EXPORT_SYMBOL_GPL(crypto_remove_spawns);
 236
 237static void crypto_alg_finish_registration(struct crypto_alg *alg,
 238                                           bool fulfill_requests,
 239                                           struct list_head *algs_to_put)
 240{
 241        struct crypto_alg *q;
 242
 243        list_for_each_entry(q, &crypto_alg_list, cra_list) {
 244                if (q == alg)
 245                        continue;
 246
 247                if (crypto_is_moribund(q))
 248                        continue;
 249
 250                if (crypto_is_larval(q)) {
 251                        struct crypto_larval *larval = (void *)q;
 252
 253                        /*
 254                         * Check to see if either our generic name or
 255                         * specific name can satisfy the name requested
 256                         * by the larval entry q.
 257                         */
 258                        if (strcmp(alg->cra_name, q->cra_name) &&
 259                            strcmp(alg->cra_driver_name, q->cra_name))
 260                                continue;
 261
 262                        if (larval->adult)
 263                                continue;
 264                        if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
 265                                continue;
 266
 267                        if (fulfill_requests && crypto_mod_get(alg))
 268                                larval->adult = alg;
 269                        else
 270                                larval->adult = ERR_PTR(-EAGAIN);
 271
 272                        continue;
 273                }
 274
 275                if (strcmp(alg->cra_name, q->cra_name))
 276                        continue;
 277
 278                if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
 279                    q->cra_priority > alg->cra_priority)
 280                        continue;
 281
 282                crypto_remove_spawns(q, algs_to_put, alg);
 283        }
 284
 285        crypto_notify(CRYPTO_MSG_ALG_LOADED, alg);
 286}
 287
 288static struct crypto_larval *crypto_alloc_test_larval(struct crypto_alg *alg)
 289{
 290        struct crypto_larval *larval;
 291
 292        if (!IS_ENABLED(CONFIG_CRYPTO_MANAGER) ||
 293            IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS) ||
 294            (alg->cra_flags & CRYPTO_ALG_INTERNAL))
 295                return NULL; /* No self-test needed */
 296
 297        larval = crypto_larval_alloc(alg->cra_name,
 298                                     alg->cra_flags | CRYPTO_ALG_TESTED, 0);
 299        if (IS_ERR(larval))
 300                return larval;
 301
 302        larval->adult = crypto_mod_get(alg);
 303        if (!larval->adult) {
 304                kfree(larval);
 305                return ERR_PTR(-ENOENT);
 306        }
 307
 308        refcount_set(&larval->alg.cra_refcnt, 1);
 309        memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
 310               CRYPTO_MAX_ALG_NAME);
 311        larval->alg.cra_priority = alg->cra_priority;
 312
 313        return larval;
 314}
 315
 316static struct crypto_larval *
 317__crypto_register_alg(struct crypto_alg *alg, struct list_head *algs_to_put)
 318{
 319        struct crypto_alg *q;
 320        struct crypto_larval *larval;
 321        int ret = -EAGAIN;
 322
 323        if (crypto_is_dead(alg))
 324                goto err;
 325
 326        INIT_LIST_HEAD(&alg->cra_users);
 327
 328        ret = -EEXIST;
 329
 330        list_for_each_entry(q, &crypto_alg_list, cra_list) {
 331                if (q == alg)
 332                        goto err;
 333
 334                if (crypto_is_moribund(q))
 335                        continue;
 336
 337                if (crypto_is_larval(q)) {
 338                        if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
 339                                goto err;
 340                        continue;
 341                }
 342
 343                if (!strcmp(q->cra_driver_name, alg->cra_name) ||
 344                    !strcmp(q->cra_name, alg->cra_driver_name))
 345                        goto err;
 346        }
 347
 348        larval = crypto_alloc_test_larval(alg);
 349        if (IS_ERR(larval))
 350                goto out;
 351
 352        list_add(&alg->cra_list, &crypto_alg_list);
 353
 354        if (larval) {
 355                /* No cheating! */
 356                alg->cra_flags &= ~CRYPTO_ALG_TESTED;
 357
 358                list_add(&larval->alg.cra_list, &crypto_alg_list);
 359        } else {
 360                alg->cra_flags |= CRYPTO_ALG_TESTED;
 361                crypto_alg_finish_registration(alg, true, algs_to_put);
 362        }
 363
 364out:
 365        return larval;
 366
 367err:
 368        larval = ERR_PTR(ret);
 369        goto out;
 370}
 371
 372void crypto_alg_tested(const char *name, int err)
 373{
 374        struct crypto_larval *test;
 375        struct crypto_alg *alg;
 376        struct crypto_alg *q;
 377        LIST_HEAD(list);
 378        bool best;
 379
 380        down_write(&crypto_alg_sem);
 381        list_for_each_entry(q, &crypto_alg_list, cra_list) {
 382                if (crypto_is_moribund(q) || !crypto_is_larval(q))
 383                        continue;
 384
 385                test = (struct crypto_larval *)q;
 386
 387                if (!strcmp(q->cra_driver_name, name))
 388                        goto found;
 389        }
 390
 391        pr_err("alg: Unexpected test result for %s: %d\n", name, err);
 392        goto unlock;
 393
 394found:
 395        q->cra_flags |= CRYPTO_ALG_DEAD;
 396        alg = test->adult;
 397
 398        if (list_empty(&alg->cra_list))
 399                goto complete;
 400
 401        if (err == -ECANCELED)
 402                alg->cra_flags |= CRYPTO_ALG_FIPS_INTERNAL;
 403        else if (err)
 404                goto complete;
 405        else
 406                alg->cra_flags &= ~CRYPTO_ALG_FIPS_INTERNAL;
 407
 408        alg->cra_flags |= CRYPTO_ALG_TESTED;
 409
 410        /*
 411         * If a higher-priority implementation of the same algorithm is
 412         * currently being tested, then don't fulfill request larvals.
 413         */
 414        best = true;
 415        list_for_each_entry(q, &crypto_alg_list, cra_list) {
 416                if (crypto_is_moribund(q) || !crypto_is_larval(q))
 417                        continue;
 418
 419                if (strcmp(alg->cra_name, q->cra_name))
 420                        continue;
 421
 422                if (q->cra_priority > alg->cra_priority) {
 423                        best = false;
 424                        break;
 425                }
 426        }
 427
 428        crypto_alg_finish_registration(alg, best, &list);
 429
 430complete:
 431        complete_all(&test->completion);
 432
 433unlock:
 434        up_write(&crypto_alg_sem);
 435
 436        crypto_remove_final(&list);
 437}
 438EXPORT_SYMBOL_GPL(crypto_alg_tested);
 439
 440void crypto_remove_final(struct list_head *list)
 441{
 442        struct crypto_alg *alg;
 443        struct crypto_alg *n;
 444
 445        list_for_each_entry_safe(alg, n, list, cra_list) {
 446                list_del_init(&alg->cra_list);
 447                crypto_alg_put(alg);
 448        }
 449}
 450EXPORT_SYMBOL_GPL(crypto_remove_final);
 451
 452int crypto_register_alg(struct crypto_alg *alg)
 453{
 454        struct crypto_larval *larval;
 455        LIST_HEAD(algs_to_put);
 456        bool test_started = false;
 457        int err;
 458
 459        alg->cra_flags &= ~CRYPTO_ALG_DEAD;
 460        err = crypto_check_alg(alg);
 461        if (err)
 462                return err;
 463
 464        down_write(&crypto_alg_sem);
 465        larval = __crypto_register_alg(alg, &algs_to_put);
 466        if (!IS_ERR_OR_NULL(larval)) {
 467                test_started = crypto_boot_test_finished();
 468                larval->test_started = test_started;
 469        }
 470        up_write(&crypto_alg_sem);
 471
 472        if (IS_ERR(larval))
 473                return PTR_ERR(larval);
 474        if (test_started)
 475                crypto_wait_for_test(larval);
 476        crypto_remove_final(&algs_to_put);
 477        return 0;
 478}
 479EXPORT_SYMBOL_GPL(crypto_register_alg);
 480
 481static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
 482{
 483        if (unlikely(list_empty(&alg->cra_list)))
 484                return -ENOENT;
 485
 486        alg->cra_flags |= CRYPTO_ALG_DEAD;
 487
 488        list_del_init(&alg->cra_list);
 489        crypto_remove_spawns(alg, list, NULL);
 490
 491        return 0;
 492}
 493
 494void crypto_unregister_alg(struct crypto_alg *alg)
 495{
 496        int ret;
 497        LIST_HEAD(list);
 498
 499        down_write(&crypto_alg_sem);
 500        ret = crypto_remove_alg(alg, &list);
 501        up_write(&crypto_alg_sem);
 502
 503        if (WARN(ret, "Algorithm %s is not registered", alg->cra_driver_name))
 504                return;
 505
 506        if (WARN_ON(refcount_read(&alg->cra_refcnt) != 1))
 507                return;
 508
 509        if (alg->cra_destroy)
 510                alg->cra_destroy(alg);
 511
 512        crypto_remove_final(&list);
 513}
 514EXPORT_SYMBOL_GPL(crypto_unregister_alg);
 515
 516int crypto_register_algs(struct crypto_alg *algs, int count)
 517{
 518        int i, ret;
 519
 520        for (i = 0; i < count; i++) {
 521                ret = crypto_register_alg(&algs[i]);
 522                if (ret)
 523                        goto err;
 524        }
 525
 526        return 0;
 527
 528err:
 529        for (--i; i >= 0; --i)
 530                crypto_unregister_alg(&algs[i]);
 531
 532        return ret;
 533}
 534EXPORT_SYMBOL_GPL(crypto_register_algs);
 535
 536void crypto_unregister_algs(struct crypto_alg *algs, int count)
 537{
 538        int i;
 539
 540        for (i = 0; i < count; i++)
 541                crypto_unregister_alg(&algs[i]);
 542}
 543EXPORT_SYMBOL_GPL(crypto_unregister_algs);
 544
 545int crypto_register_template(struct crypto_template *tmpl)
 546{
 547        struct crypto_template *q;
 548        int err = -EEXIST;
 549
 550        down_write(&crypto_alg_sem);
 551
 552        crypto_check_module_sig(tmpl->module);
 553
 554        list_for_each_entry(q, &crypto_template_list, list) {
 555                if (q == tmpl)
 556                        goto out;
 557        }
 558
 559        list_add(&tmpl->list, &crypto_template_list);
 560        err = 0;
 561out:
 562        up_write(&crypto_alg_sem);
 563        return err;
 564}
 565EXPORT_SYMBOL_GPL(crypto_register_template);
 566
 567int crypto_register_templates(struct crypto_template *tmpls, int count)
 568{
 569        int i, err;
 570
 571        for (i = 0; i < count; i++) {
 572                err = crypto_register_template(&tmpls[i]);
 573                if (err)
 574                        goto out;
 575        }
 576        return 0;
 577
 578out:
 579        for (--i; i >= 0; --i)
 580                crypto_unregister_template(&tmpls[i]);
 581        return err;
 582}
 583EXPORT_SYMBOL_GPL(crypto_register_templates);
 584
 585void crypto_unregister_template(struct crypto_template *tmpl)
 586{
 587        struct crypto_instance *inst;
 588        struct hlist_node *n;
 589        struct hlist_head *list;
 590        LIST_HEAD(users);
 591
 592        down_write(&crypto_alg_sem);
 593
 594        BUG_ON(list_empty(&tmpl->list));
 595        list_del_init(&tmpl->list);
 596
 597        list = &tmpl->instances;
 598        hlist_for_each_entry(inst, list, list) {
 599                int err = crypto_remove_alg(&inst->alg, &users);
 600
 601                BUG_ON(err);
 602        }
 603
 604        up_write(&crypto_alg_sem);
 605
 606        hlist_for_each_entry_safe(inst, n, list, list) {
 607                BUG_ON(refcount_read(&inst->alg.cra_refcnt) != 1);
 608                crypto_free_instance(inst);
 609        }
 610        crypto_remove_final(&users);
 611}
 612EXPORT_SYMBOL_GPL(crypto_unregister_template);
 613
 614void crypto_unregister_templates(struct crypto_template *tmpls, int count)
 615{
 616        int i;
 617
 618        for (i = count - 1; i >= 0; --i)
 619                crypto_unregister_template(&tmpls[i]);
 620}
 621EXPORT_SYMBOL_GPL(crypto_unregister_templates);
 622
 623static struct crypto_template *__crypto_lookup_template(const char *name)
 624{
 625        struct crypto_template *q, *tmpl = NULL;
 626
 627        down_read(&crypto_alg_sem);
 628        list_for_each_entry(q, &crypto_template_list, list) {
 629                if (strcmp(q->name, name))
 630                        continue;
 631                if (unlikely(!crypto_tmpl_get(q)))
 632                        continue;
 633
 634                tmpl = q;
 635                break;
 636        }
 637        up_read(&crypto_alg_sem);
 638
 639        return tmpl;
 640}
 641
 642struct crypto_template *crypto_lookup_template(const char *name)
 643{
 644        return try_then_request_module(__crypto_lookup_template(name),
 645                                       "crypto-%s", name);
 646}
 647EXPORT_SYMBOL_GPL(crypto_lookup_template);
 648
 649int crypto_register_instance(struct crypto_template *tmpl,
 650                             struct crypto_instance *inst)
 651{
 652        struct crypto_larval *larval;
 653        struct crypto_spawn *spawn;
 654        u32 fips_internal = 0;
 655        LIST_HEAD(algs_to_put);
 656        int err;
 657
 658        err = crypto_check_alg(&inst->alg);
 659        if (err)
 660                return err;
 661
 662        inst->alg.cra_module = tmpl->module;
 663        inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;
 664
 665        down_write(&crypto_alg_sem);
 666
 667        larval = ERR_PTR(-EAGAIN);
 668        for (spawn = inst->spawns; spawn;) {
 669                struct crypto_spawn *next;
 670
 671                if (spawn->dead)
 672                        goto unlock;
 673
 674                next = spawn->next;
 675                spawn->inst = inst;
 676                spawn->registered = true;
 677
 678                fips_internal |= spawn->alg->cra_flags;
 679
 680                crypto_mod_put(spawn->alg);
 681
 682                spawn = next;
 683        }
 684
 685        inst->alg.cra_flags |= (fips_internal & CRYPTO_ALG_FIPS_INTERNAL);
 686
 687        larval = __crypto_register_alg(&inst->alg, &algs_to_put);
 688        if (IS_ERR(larval))
 689                goto unlock;
 690        else if (larval)
 691                larval->test_started = true;
 692
 693        hlist_add_head(&inst->list, &tmpl->instances);
 694        inst->tmpl = tmpl;
 695
 696unlock:
 697        up_write(&crypto_alg_sem);
 698
 699        if (IS_ERR(larval))
 700                return PTR_ERR(larval);
 701        if (larval)
 702                crypto_wait_for_test(larval);
 703        crypto_remove_final(&algs_to_put);
 704        return 0;
 705}
 706EXPORT_SYMBOL_GPL(crypto_register_instance);
 707
 708void crypto_unregister_instance(struct crypto_instance *inst)
 709{
 710        LIST_HEAD(list);
 711
 712        down_write(&crypto_alg_sem);
 713
 714        crypto_remove_spawns(&inst->alg, &list, NULL);
 715        crypto_remove_instance(inst, &list);
 716
 717        up_write(&crypto_alg_sem);
 718
 719        crypto_remove_final(&list);
 720}
 721EXPORT_SYMBOL_GPL(crypto_unregister_instance);
 722
 723int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
 724                      const char *name, u32 type, u32 mask)
 725{
 726        struct crypto_alg *alg;
 727        int err = -EAGAIN;
 728
 729        if (WARN_ON_ONCE(inst == NULL))
 730                return -EINVAL;
 731
 732        /* Allow the result of crypto_attr_alg_name() to be passed directly */
 733        if (IS_ERR(name))
 734                return PTR_ERR(name);
 735
 736        alg = crypto_find_alg(name, spawn->frontend,
 737                              type | CRYPTO_ALG_FIPS_INTERNAL, mask);
 738        if (IS_ERR(alg))
 739                return PTR_ERR(alg);
 740
 741        down_write(&crypto_alg_sem);
 742        if (!crypto_is_moribund(alg)) {
 743                list_add(&spawn->list, &alg->cra_users);
 744                spawn->alg = alg;
 745                spawn->mask = mask;
 746                spawn->next = inst->spawns;
 747                inst->spawns = spawn;
 748                inst->alg.cra_flags |=
 749                        (alg->cra_flags & CRYPTO_ALG_INHERITED_FLAGS);
 750                err = 0;
 751        }
 752        up_write(&crypto_alg_sem);
 753        if (err)
 754                crypto_mod_put(alg);
 755        return err;
 756}
 757EXPORT_SYMBOL_GPL(crypto_grab_spawn);
 758
 759void crypto_drop_spawn(struct crypto_spawn *spawn)
 760{
 761        if (!spawn->alg) /* not yet initialized? */
 762                return;
 763
 764        down_write(&crypto_alg_sem);
 765        if (!spawn->dead)
 766                list_del(&spawn->list);
 767        up_write(&crypto_alg_sem);
 768
 769        if (!spawn->registered)
 770                crypto_mod_put(spawn->alg);
 771}
 772EXPORT_SYMBOL_GPL(crypto_drop_spawn);
 773
 774static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
 775{
 776        struct crypto_alg *alg = ERR_PTR(-EAGAIN);
 777        struct crypto_alg *target;
 778        bool shoot = false;
 779
 780        down_read(&crypto_alg_sem);
 781        if (!spawn->dead) {
 782                alg = spawn->alg;
 783                if (!crypto_mod_get(alg)) {
 784                        target = crypto_alg_get(alg);
 785                        shoot = true;
 786                        alg = ERR_PTR(-EAGAIN);
 787                }
 788        }
 789        up_read(&crypto_alg_sem);
 790
 791        if (shoot) {
 792                crypto_shoot_alg(target);
 793                crypto_alg_put(target);
 794        }
 795
 796        return alg;
 797}
 798
 799struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
 800                                    u32 mask)
 801{
 802        struct crypto_alg *alg;
 803        struct crypto_tfm *tfm;
 804
 805        alg = crypto_spawn_alg(spawn);
 806        if (IS_ERR(alg))
 807                return ERR_CAST(alg);
 808
 809        tfm = ERR_PTR(-EINVAL);
 810        if (unlikely((alg->cra_flags ^ type) & mask))
 811                goto out_put_alg;
 812
 813        tfm = __crypto_alloc_tfm(alg, type, mask);
 814        if (IS_ERR(tfm))
 815                goto out_put_alg;
 816
 817        return tfm;
 818
 819out_put_alg:
 820        crypto_mod_put(alg);
 821        return tfm;
 822}
 823EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
 824
 825void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
 826{
 827        struct crypto_alg *alg;
 828        struct crypto_tfm *tfm;
 829
 830        alg = crypto_spawn_alg(spawn);
 831        if (IS_ERR(alg))
 832                return ERR_CAST(alg);
 833
 834        tfm = crypto_create_tfm(alg, spawn->frontend);
 835        if (IS_ERR(tfm))
 836                goto out_put_alg;
 837
 838        return tfm;
 839
 840out_put_alg:
 841        crypto_mod_put(alg);
 842        return tfm;
 843}
 844EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
 845
 846int crypto_register_notifier(struct notifier_block *nb)
 847{
 848        return blocking_notifier_chain_register(&crypto_chain, nb);
 849}
 850EXPORT_SYMBOL_GPL(crypto_register_notifier);
 851
 852int crypto_unregister_notifier(struct notifier_block *nb)
 853{
 854        return blocking_notifier_chain_unregister(&crypto_chain, nb);
 855}
 856EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
 857
 858struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)
 859{
 860        struct rtattr *rta = tb[0];
 861        struct crypto_attr_type *algt;
 862
 863        if (!rta)
 864                return ERR_PTR(-ENOENT);
 865        if (RTA_PAYLOAD(rta) < sizeof(*algt))
 866                return ERR_PTR(-EINVAL);
 867        if (rta->rta_type != CRYPTOA_TYPE)
 868                return ERR_PTR(-EINVAL);
 869
 870        algt = RTA_DATA(rta);
 871
 872        return algt;
 873}
 874EXPORT_SYMBOL_GPL(crypto_get_attr_type);
 875
 876/**
 877 * crypto_check_attr_type() - check algorithm type and compute inherited mask
 878 * @tb: the template parameters
 879 * @type: the algorithm type the template would be instantiated as
 880 * @mask_ret: (output) the mask that should be passed to crypto_grab_*()
 881 *            to restrict the flags of any inner algorithms
 882 *
 883 * Validate that the algorithm type the user requested is compatible with the
 884 * one the template would actually be instantiated as.  E.g., if the user is
 885 * doing crypto_alloc_shash("cbc(aes)", ...), this would return an error because
 886 * the "cbc" template creates an "skcipher" algorithm, not an "shash" algorithm.
 887 *
 888 * Also compute the mask to use to restrict the flags of any inner algorithms.
 889 *
 890 * Return: 0 on success; -errno on failure
 891 */
 892int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret)
 893{
 894        struct crypto_attr_type *algt;
 895
 896        algt = crypto_get_attr_type(tb);
 897        if (IS_ERR(algt))
 898                return PTR_ERR(algt);
 899
 900        if ((algt->type ^ type) & algt->mask)
 901                return -EINVAL;
 902
 903        *mask_ret = crypto_algt_inherited_mask(algt);
 904        return 0;
 905}
 906EXPORT_SYMBOL_GPL(crypto_check_attr_type);
 907
 908const char *crypto_attr_alg_name(struct rtattr *rta)
 909{
 910        struct crypto_attr_alg *alga;
 911
 912        if (!rta)
 913                return ERR_PTR(-ENOENT);
 914        if (RTA_PAYLOAD(rta) < sizeof(*alga))
 915                return ERR_PTR(-EINVAL);
 916        if (rta->rta_type != CRYPTOA_ALG)
 917                return ERR_PTR(-EINVAL);
 918
 919        alga = RTA_DATA(rta);
 920        alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
 921
 922        return alga->name;
 923}
 924EXPORT_SYMBOL_GPL(crypto_attr_alg_name);
 925
 926int crypto_inst_setname(struct crypto_instance *inst, const char *name,
 927                        struct crypto_alg *alg)
 928{
 929        if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
 930                     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
 931                return -ENAMETOOLONG;
 932
 933        if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
 934                     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 935                return -ENAMETOOLONG;
 936
 937        return 0;
 938}
 939EXPORT_SYMBOL_GPL(crypto_inst_setname);
 940
 941void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
 942{
 943        INIT_LIST_HEAD(&queue->list);
 944        queue->backlog = &queue->list;
 945        queue->qlen = 0;
 946        queue->max_qlen = max_qlen;
 947}
 948EXPORT_SYMBOL_GPL(crypto_init_queue);
 949
 950int crypto_enqueue_request(struct crypto_queue *queue,
 951                           struct crypto_async_request *request)
 952{
 953        int err = -EINPROGRESS;
 954
 955        if (unlikely(queue->qlen >= queue->max_qlen)) {
 956                if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
 957                        err = -ENOSPC;
 958                        goto out;
 959                }
 960                err = -EBUSY;
 961                if (queue->backlog == &queue->list)
 962                        queue->backlog = &request->list;
 963        }
 964
 965        queue->qlen++;
 966        list_add_tail(&request->list, &queue->list);
 967
 968out:
 969        return err;
 970}
 971EXPORT_SYMBOL_GPL(crypto_enqueue_request);
 972
 973void crypto_enqueue_request_head(struct crypto_queue *queue,
 974                                 struct crypto_async_request *request)
 975{
 976        if (unlikely(queue->qlen >= queue->max_qlen))
 977                queue->backlog = queue->backlog->prev;
 978
 979        queue->qlen++;
 980        list_add(&request->list, &queue->list);
 981}
 982EXPORT_SYMBOL_GPL(crypto_enqueue_request_head);
 983
 984struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
 985{
 986        struct list_head *request;
 987
 988        if (unlikely(!queue->qlen))
 989                return NULL;
 990
 991        queue->qlen--;
 992
 993        if (queue->backlog != &queue->list)
 994                queue->backlog = queue->backlog->next;
 995
 996        request = queue->list.next;
 997        list_del(request);
 998
 999        return list_entry(request, struct crypto_async_request, list);
1000}
1001EXPORT_SYMBOL_GPL(crypto_dequeue_request);
1002
1003static inline void crypto_inc_byte(u8 *a, unsigned int size)
1004{
1005        u8 *b = (a + size);
1006        u8 c;
1007
1008        for (; size; size--) {
1009                c = *--b + 1;
1010                *b = c;
1011                if (c)
1012                        break;
1013        }
1014}
1015
1016void crypto_inc(u8 *a, unsigned int size)
1017{
1018        __be32 *b = (__be32 *)(a + size);
1019        u32 c;
1020
1021        if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
1022            IS_ALIGNED((unsigned long)b, __alignof__(*b)))
1023                for (; size >= 4; size -= 4) {
1024                        c = be32_to_cpu(*--b) + 1;
1025                        *b = cpu_to_be32(c);
1026                        if (likely(c))
1027                                return;
1028                }
1029
1030        crypto_inc_byte(a, size);
1031}
1032EXPORT_SYMBOL_GPL(crypto_inc);
1033
1034unsigned int crypto_alg_extsize(struct crypto_alg *alg)
1035{
1036        return alg->cra_ctxsize +
1037               (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));
1038}
1039EXPORT_SYMBOL_GPL(crypto_alg_extsize);
1040
1041int crypto_type_has_alg(const char *name, const struct crypto_type *frontend,
1042                        u32 type, u32 mask)
1043{
1044        int ret = 0;
1045        struct crypto_alg *alg = crypto_find_alg(name, frontend, type, mask);
1046
1047        if (!IS_ERR(alg)) {
1048                crypto_mod_put(alg);
1049                ret = 1;
1050        }
1051
1052        return ret;
1053}
1054EXPORT_SYMBOL_GPL(crypto_type_has_alg);
1055
1056static void __init crypto_start_tests(void)
1057{
1058        if (IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS))
1059                return;
1060
1061        for (;;) {
1062                struct crypto_larval *larval = NULL;
1063                struct crypto_alg *q;
1064
1065                down_write(&crypto_alg_sem);
1066
1067                list_for_each_entry(q, &crypto_alg_list, cra_list) {
1068                        struct crypto_larval *l;
1069
1070                        if (!crypto_is_larval(q))
1071                                continue;
1072
1073                        l = (void *)q;
1074
1075                        if (!crypto_is_test_larval(l))
1076                                continue;
1077
1078                        if (l->test_started)
1079                                continue;
1080
1081                        l->test_started = true;
1082                        larval = l;
1083                        break;
1084                }
1085
1086                up_write(&crypto_alg_sem);
1087
1088                if (!larval)
1089                        break;
1090
1091                crypto_wait_for_test(larval);
1092        }
1093
1094        set_crypto_boot_test_finished();
1095}
1096
1097static int __init crypto_algapi_init(void)
1098{
1099        crypto_init_proc();
1100        crypto_start_tests();
1101        return 0;
1102}
1103
1104static void __exit crypto_algapi_exit(void)
1105{
1106        crypto_exit_proc();
1107}
1108
1109/*
1110 * We run this at late_initcall so that all the built-in algorithms
1111 * have had a chance to register themselves first.
1112 */
1113late_initcall(crypto_algapi_init);
1114module_exit(crypto_algapi_exit);
1115
1116MODULE_LICENSE("GPL");
1117MODULE_DESCRIPTION("Cryptographic algorithms API");
1118MODULE_SOFTDEP("pre: cryptomgr");
1119