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