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