1 // SPDX-License-Identifier: BSD-2-Clause 2 /* 3 * Copyright (c) 2017, Linaro Limited 4 */ 5 6 #include <assert.h> 7 #include <config.h> 8 #include <crypto/crypto.h> 9 #include <initcall.h> 10 #include <kernel/tee_common_otp.h> 11 #include <stdlib.h> 12 #include <string_ext.h> 13 #include <string.h> 14 #include <tee/fs_htree.h> 15 #include <tee/tee_fs_key_manager.h> 16 #include <tee/tee_fs_rpc.h> 17 #include <utee_defines.h> 18 #include <util.h> 19 20 #define TEE_FS_HTREE_CHIP_ID_SIZE 32 21 #define TEE_FS_HTREE_HASH_ALG TEE_ALG_SHA256 22 #define TEE_FS_HTREE_TSK_SIZE TEE_FS_HTREE_HASH_SIZE 23 #define TEE_FS_HTREE_ENC_ALG TEE_ALG_AES_ECB_NOPAD 24 #define TEE_FS_HTREE_ENC_SIZE TEE_AES_BLOCK_SIZE 25 #define TEE_FS_HTREE_SSK_SIZE TEE_FS_HTREE_HASH_SIZE 26 27 #define TEE_FS_HTREE_AUTH_ENC_ALG TEE_ALG_AES_GCM 28 #define TEE_FS_HTREE_HMAC_ALG TEE_ALG_HMAC_SHA256 29 30 #define BLOCK_NUM_TO_NODE_ID(num) ((num) + 1) 31 32 #define NODE_ID_TO_BLOCK_NUM(id) ((id) - 1) 33 34 /* 35 * The hash tree is implemented as a binary tree with the purpose to ensure 36 * integrity of the data in the nodes. The data in the nodes their turn 37 * provides both integrity and confidentiality of the data blocks. 38 * 39 * The hash tree is saved in a file as: 40 * +----------------------------+ 41 * | htree_image.0 | 42 * | htree_image.1 | 43 * +----------------------------+ 44 * | htree_node_image.1.0 | 45 * | htree_node_image.1.1 | 46 * +----------------------------+ 47 * | htree_node_image.2.0 | 48 * | htree_node_image.2.1 | 49 * +----------------------------+ 50 * | htree_node_image.3.0 | 51 * | htree_node_image.3.1 | 52 * +----------------------------+ 53 * | htree_node_image.4.0 | 54 * | htree_node_image.4.1 | 55 * +----------------------------+ 56 * ... 57 * 58 * htree_image is the header of the file, there's two instances of it. One 59 * which is committed and the other is used when updating the file. Which 60 * is committed is indicated by the "counter" field, the one with the 61 * largest value is selected. 62 * 63 * htree_node_image is a node in the hash tree, each node has two instances 64 * which is committed is decided by the parent node .flag bit 65 * HTREE_NODE_COMMITTED_CHILD. Which version is the committed version of 66 * node 1 is determined by the by the lowest bit of the counter field in 67 * the header. 68 * 69 * Note that nodes start counting at 1 while blocks at 0, this means that 70 * block 0 is represented by node 1. 71 * 72 * Where different elements are stored in the file is managed by the file 73 * system. 74 */ 75 76 #define HTREE_NODE_COMMITTED_BLOCK BIT32(0) 77 /* n is 0 or 1 */ 78 #define HTREE_NODE_COMMITTED_CHILD(n) BIT32(1 + (n)) 79 80 struct htree_node { 81 size_t id; 82 bool dirty; 83 bool block_updated; 84 struct tee_fs_htree_node_image node; 85 struct htree_node *parent; 86 struct htree_node *child[2]; 87 }; 88 89 struct tee_fs_htree { 90 struct htree_node root; 91 struct tee_fs_htree_image head; 92 uint8_t fek[TEE_FS_HTREE_FEK_SIZE]; 93 struct tee_fs_htree_imeta imeta; 94 bool dirty; 95 const TEE_UUID *uuid; 96 const struct tee_fs_htree_storage *stor; 97 void *stor_aux; 98 }; 99 100 struct traverse_arg; 101 typedef TEE_Result (*traverse_cb_t)(struct traverse_arg *targ, 102 struct htree_node *node); 103 struct traverse_arg { 104 struct tee_fs_htree *ht; 105 traverse_cb_t cb; 106 void *arg; 107 }; 108 109 static TEE_Result rpc_read(struct tee_fs_htree *ht, enum tee_fs_htree_type type, 110 size_t idx, size_t vers, void *data, size_t dlen) 111 { 112 TEE_Result res; 113 struct tee_fs_rpc_operation op; 114 size_t bytes; 115 void *p; 116 117 res = ht->stor->rpc_read_init(ht->stor_aux, &op, type, idx, vers, &p); 118 if (res != TEE_SUCCESS) 119 return res; 120 121 res = ht->stor->rpc_read_final(&op, &bytes); 122 if (res != TEE_SUCCESS) 123 return res; 124 125 if (bytes != dlen) 126 return TEE_ERROR_CORRUPT_OBJECT; 127 128 memcpy(data, p, dlen); 129 return TEE_SUCCESS; 130 } 131 132 static TEE_Result rpc_read_head(struct tee_fs_htree *ht, size_t vers, 133 struct tee_fs_htree_image *head) 134 { 135 return rpc_read(ht, TEE_FS_HTREE_TYPE_HEAD, 0, vers, 136 head, sizeof(*head)); 137 } 138 139 static TEE_Result rpc_read_node(struct tee_fs_htree *ht, size_t node_id, 140 size_t vers, 141 struct tee_fs_htree_node_image *node) 142 { 143 return rpc_read(ht, TEE_FS_HTREE_TYPE_NODE, node_id - 1, vers, 144 node, sizeof(*node)); 145 } 146 147 static TEE_Result rpc_write(struct tee_fs_htree *ht, 148 enum tee_fs_htree_type type, size_t idx, 149 size_t vers, const void *data, size_t dlen) 150 { 151 TEE_Result res; 152 struct tee_fs_rpc_operation op; 153 void *p; 154 155 res = ht->stor->rpc_write_init(ht->stor_aux, &op, type, idx, vers, &p); 156 if (res != TEE_SUCCESS) 157 return res; 158 159 memcpy(p, data, dlen); 160 return ht->stor->rpc_write_final(&op); 161 } 162 163 static TEE_Result rpc_write_head(struct tee_fs_htree *ht, size_t vers, 164 const struct tee_fs_htree_image *head) 165 { 166 return rpc_write(ht, TEE_FS_HTREE_TYPE_HEAD, 0, vers, 167 head, sizeof(*head)); 168 } 169 170 static TEE_Result rpc_write_node(struct tee_fs_htree *ht, size_t node_id, 171 size_t vers, 172 const struct tee_fs_htree_node_image *node) 173 { 174 return rpc_write(ht, TEE_FS_HTREE_TYPE_NODE, node_id - 1, vers, 175 node, sizeof(*node)); 176 } 177 178 static TEE_Result traverse_post_order(struct traverse_arg *targ, 179 struct htree_node *node) 180 { 181 TEE_Result res; 182 183 /* 184 * This function is recursing but not very deep, only with Log(N) 185 * maximum depth. 186 */ 187 188 if (!node) 189 return TEE_SUCCESS; 190 191 res = traverse_post_order(targ, node->child[0]); 192 if (res != TEE_SUCCESS) 193 return res; 194 195 res = traverse_post_order(targ, node->child[1]); 196 if (res != TEE_SUCCESS) 197 return res; 198 199 return targ->cb(targ, node); 200 } 201 202 static TEE_Result htree_traverse_post_order(struct tee_fs_htree *ht, 203 traverse_cb_t cb, void *arg) 204 { 205 struct traverse_arg targ = { ht, cb, arg }; 206 207 return traverse_post_order(&targ, &ht->root); 208 } 209 210 static size_t node_id_to_level(size_t node_id) 211 { 212 assert(node_id && node_id < UINT_MAX); 213 /* Calculate level of the node, root node (1) has level 1 */ 214 return sizeof(unsigned int) * 8 - __builtin_clz(node_id); 215 } 216 217 static struct htree_node *find_closest_node(struct tee_fs_htree *ht, 218 size_t node_id) 219 { 220 struct htree_node *node = &ht->root; 221 size_t level = node_id_to_level(node_id); 222 size_t n; 223 224 /* n = 1 because root node is level 1 */ 225 for (n = 1; n < level; n++) { 226 struct htree_node *child; 227 size_t bit_idx; 228 229 /* 230 * The difference between levels of the current node and 231 * the node we're looking for tells which bit decides 232 * direction in the tree. 233 * 234 * As the first bit has index 0 we'll subtract 1 235 */ 236 bit_idx = level - n - 1; 237 child = node->child[((node_id >> bit_idx) & 1)]; 238 if (!child) 239 return node; 240 node = child; 241 } 242 243 return node; 244 } 245 246 static struct htree_node *find_node(struct tee_fs_htree *ht, size_t node_id) 247 { 248 struct htree_node *node = find_closest_node(ht, node_id); 249 250 if (node && node->id == node_id) 251 return node; 252 return NULL; 253 } 254 255 static TEE_Result get_node(struct tee_fs_htree *ht, bool create, 256 size_t node_id, struct htree_node **node_ret) 257 { 258 struct htree_node *node; 259 struct htree_node *nc; 260 size_t n; 261 262 node = find_closest_node(ht, node_id); 263 if (!node) 264 return TEE_ERROR_GENERIC; 265 if (node->id == node_id) 266 goto ret_node; 267 268 /* 269 * Trying to read beyond end of file should be caught earlier than 270 * here. 271 */ 272 if (!create) 273 return TEE_ERROR_GENERIC; 274 275 /* 276 * Add missing nodes, some nodes may already be there. When we've 277 * processed the range all nodes up to node_id will be in the tree. 278 */ 279 for (n = node->id + 1; n <= node_id; n++) { 280 node = find_closest_node(ht, n); 281 if (node->id == n) 282 continue; 283 /* Node id n should be a child of node */ 284 assert((n >> 1) == node->id); 285 assert(!node->child[n & 1]); 286 287 nc = calloc(1, sizeof(*nc)); 288 if (!nc) 289 return TEE_ERROR_OUT_OF_MEMORY; 290 nc->id = n; 291 nc->parent = node; 292 node->child[n & 1] = nc; 293 node = nc; 294 } 295 296 if (node->id > ht->imeta.max_node_id) 297 ht->imeta.max_node_id = node->id; 298 299 ret_node: 300 *node_ret = node; 301 return TEE_SUCCESS; 302 } 303 304 static int get_idx_from_counter(uint32_t counter0, uint32_t counter1) 305 { 306 if (!(counter0 & 1)) { 307 if (!(counter1 & 1)) 308 return 0; 309 if (counter0 > counter1) 310 return 0; 311 else 312 return 1; 313 } 314 315 if (counter1 & 1) 316 return 1; 317 else 318 return -1; 319 } 320 321 static TEE_Result init_head_from_data(struct tee_fs_htree *ht, 322 const uint8_t *hash, uint32_t min_counter) 323 { 324 TEE_Result res; 325 int idx; 326 327 if (hash) { 328 for (idx = 0;; idx++) { 329 res = rpc_read_node(ht, 1, idx, &ht->root.node); 330 if (res != TEE_SUCCESS) 331 return res; 332 333 if (!memcmp(ht->root.node.hash, hash, 334 sizeof(ht->root.node.hash))) { 335 res = rpc_read_head(ht, idx, &ht->head); 336 if (res != TEE_SUCCESS) 337 return res; 338 break; 339 } 340 341 if (idx) 342 return TEE_ERROR_CORRUPT_OBJECT; 343 } 344 } else { 345 struct tee_fs_htree_image head[2]; 346 347 for (idx = 0; idx < 2; idx++) { 348 res = rpc_read_head(ht, idx, head + idx); 349 if (res != TEE_SUCCESS) 350 return res; 351 } 352 353 idx = get_idx_from_counter(head[0].counter, head[1].counter); 354 if (idx < 0) 355 return TEE_ERROR_SECURITY; 356 357 res = rpc_read_node(ht, 1, idx, &ht->root.node); 358 if (res != TEE_SUCCESS) 359 return res; 360 361 ht->head = head[idx]; 362 } 363 364 if (ht->head.counter < min_counter) 365 return TEE_ERROR_SECURITY; 366 367 ht->root.id = 1; 368 369 return TEE_SUCCESS; 370 } 371 372 static TEE_Result init_tree_from_data(struct tee_fs_htree *ht) 373 { 374 TEE_Result res; 375 struct tee_fs_htree_node_image node_image; 376 struct htree_node *node; 377 struct htree_node *nc; 378 size_t committed_version; 379 size_t node_id = 2; 380 381 while (node_id <= ht->imeta.max_node_id) { 382 node = find_node(ht, node_id >> 1); 383 if (!node) 384 return TEE_ERROR_GENERIC; 385 committed_version = !!(node->node.flags & 386 HTREE_NODE_COMMITTED_CHILD(node_id & 1)); 387 388 res = rpc_read_node(ht, node_id, committed_version, 389 &node_image); 390 if (res != TEE_SUCCESS) 391 return res; 392 393 res = get_node(ht, true, node_id, &nc); 394 if (res != TEE_SUCCESS) 395 return res; 396 nc->node = node_image; 397 node_id++; 398 } 399 400 return TEE_SUCCESS; 401 } 402 403 static TEE_Result calc_node_hash(struct htree_node *node, 404 struct tee_fs_htree_meta *meta, void *ctx, 405 uint8_t *digest) 406 { 407 TEE_Result res; 408 uint8_t *ndata = (uint8_t *)&node->node + sizeof(node->node.hash); 409 size_t nsize = sizeof(node->node) - sizeof(node->node.hash); 410 411 res = crypto_hash_init(ctx); 412 if (res != TEE_SUCCESS) 413 return res; 414 415 res = crypto_hash_update(ctx, ndata, nsize); 416 if (res != TEE_SUCCESS) 417 return res; 418 419 if (meta) { 420 res = crypto_hash_update(ctx, (void *)meta, sizeof(*meta)); 421 if (res != TEE_SUCCESS) 422 return res; 423 } 424 425 if (node->child[0]) { 426 res = crypto_hash_update(ctx, node->child[0]->node.hash, 427 sizeof(node->child[0]->node.hash)); 428 if (res != TEE_SUCCESS) 429 return res; 430 } 431 432 if (node->child[1]) { 433 res = crypto_hash_update(ctx, node->child[1]->node.hash, 434 sizeof(node->child[1]->node.hash)); 435 if (res != TEE_SUCCESS) 436 return res; 437 } 438 439 return crypto_hash_final(ctx, digest, TEE_FS_HTREE_HASH_SIZE); 440 } 441 442 static TEE_Result authenc_init(void **ctx_ret, TEE_OperationMode mode, 443 struct tee_fs_htree *ht, 444 struct tee_fs_htree_node_image *ni, 445 size_t payload_len) 446 { 447 TEE_Result res = TEE_SUCCESS; 448 const uint32_t alg = TEE_FS_HTREE_AUTH_ENC_ALG; 449 void *ctx; 450 size_t aad_len = TEE_FS_HTREE_FEK_SIZE + TEE_FS_HTREE_IV_SIZE; 451 uint8_t *iv; 452 453 if (ni) { 454 iv = ni->iv; 455 } else { 456 iv = ht->head.iv; 457 aad_len += TEE_FS_HTREE_HASH_SIZE + sizeof(ht->head.counter); 458 } 459 460 if (mode == TEE_MODE_ENCRYPT) { 461 res = crypto_rng_read(iv, TEE_FS_HTREE_IV_SIZE); 462 if (res != TEE_SUCCESS) 463 return res; 464 } 465 466 res = crypto_authenc_alloc_ctx(&ctx, alg); 467 if (res != TEE_SUCCESS) 468 return res; 469 470 res = crypto_authenc_init(ctx, mode, ht->fek, TEE_FS_HTREE_FEK_SIZE, iv, 471 TEE_FS_HTREE_IV_SIZE, TEE_FS_HTREE_TAG_SIZE, 472 aad_len, payload_len); 473 if (res != TEE_SUCCESS) 474 goto err_free; 475 476 if (!ni) { 477 size_t hash_size = TEE_FS_HTREE_HASH_SIZE; 478 479 if (IS_ENABLED(CFG_REE_FS_HTREE_HASH_SIZE_COMPAT)) 480 hash_size = TEE_FS_HTREE_FEK_SIZE; 481 482 res = crypto_authenc_update_aad(ctx, mode, ht->root.node.hash, 483 hash_size); 484 if (res != TEE_SUCCESS) 485 goto err; 486 487 res = crypto_authenc_update_aad(ctx, mode, 488 (void *)&ht->head.counter, 489 sizeof(ht->head.counter)); 490 if (res != TEE_SUCCESS) 491 goto err; 492 } 493 494 res = crypto_authenc_update_aad(ctx, mode, ht->head.enc_fek, 495 TEE_FS_HTREE_FEK_SIZE); 496 if (res != TEE_SUCCESS) 497 goto err; 498 499 res = crypto_authenc_update_aad(ctx, mode, iv, TEE_FS_HTREE_IV_SIZE); 500 if (res != TEE_SUCCESS) 501 goto err; 502 503 *ctx_ret = ctx; 504 505 return TEE_SUCCESS; 506 err: 507 crypto_authenc_final(ctx); 508 err_free: 509 crypto_authenc_free_ctx(ctx); 510 return res; 511 } 512 513 static TEE_Result authenc_decrypt_final(void *ctx, const uint8_t *tag, 514 const void *crypt, size_t len, 515 void *plain) 516 { 517 TEE_Result res; 518 size_t out_size = len; 519 520 res = crypto_authenc_dec_final(ctx, crypt, len, plain, &out_size, tag, 521 TEE_FS_HTREE_TAG_SIZE); 522 crypto_authenc_final(ctx); 523 crypto_authenc_free_ctx(ctx); 524 525 if (res == TEE_SUCCESS && out_size != len) 526 return TEE_ERROR_GENERIC; 527 if (res == TEE_ERROR_MAC_INVALID) 528 return TEE_ERROR_CORRUPT_OBJECT; 529 530 return res; 531 } 532 533 static TEE_Result authenc_encrypt_final(void *ctx, uint8_t *tag, 534 const void *plain, size_t len, 535 void *crypt) 536 { 537 TEE_Result res; 538 size_t out_size = len; 539 size_t out_tag_size = TEE_FS_HTREE_TAG_SIZE; 540 541 res = crypto_authenc_enc_final(ctx, plain, len, crypt, &out_size, tag, 542 &out_tag_size); 543 crypto_authenc_final(ctx); 544 crypto_authenc_free_ctx(ctx); 545 546 if (res == TEE_SUCCESS && 547 (out_size != len || out_tag_size != TEE_FS_HTREE_TAG_SIZE)) 548 return TEE_ERROR_GENERIC; 549 550 return res; 551 } 552 553 static TEE_Result verify_root(struct tee_fs_htree *ht) 554 { 555 TEE_Result res; 556 void *ctx; 557 558 res = tee_fs_fek_crypt(ht->uuid, TEE_MODE_DECRYPT, ht->head.enc_fek, 559 sizeof(ht->fek), ht->fek); 560 if (res != TEE_SUCCESS) 561 return res; 562 563 res = authenc_init(&ctx, TEE_MODE_DECRYPT, ht, NULL, sizeof(ht->imeta)); 564 if (res != TEE_SUCCESS) 565 return res; 566 567 return authenc_decrypt_final(ctx, ht->head.tag, ht->head.imeta, 568 sizeof(ht->imeta), &ht->imeta); 569 } 570 571 static TEE_Result verify_node(struct traverse_arg *targ, 572 struct htree_node *node) 573 { 574 void *ctx = targ->arg; 575 TEE_Result res; 576 uint8_t digest[TEE_FS_HTREE_HASH_SIZE]; 577 578 if (node->parent) 579 res = calc_node_hash(node, NULL, ctx, digest); 580 else 581 res = calc_node_hash(node, &targ->ht->imeta.meta, ctx, digest); 582 if (res == TEE_SUCCESS && 583 consttime_memcmp(digest, node->node.hash, sizeof(digest))) 584 return TEE_ERROR_CORRUPT_OBJECT; 585 586 return res; 587 } 588 589 static TEE_Result verify_tree(struct tee_fs_htree *ht) 590 { 591 TEE_Result res; 592 void *ctx; 593 594 res = crypto_hash_alloc_ctx(&ctx, TEE_FS_HTREE_HASH_ALG); 595 if (res != TEE_SUCCESS) 596 return res; 597 598 res = htree_traverse_post_order(ht, verify_node, ctx); 599 crypto_hash_free_ctx(ctx); 600 601 return res; 602 } 603 604 static TEE_Result init_root_node(struct tee_fs_htree *ht) 605 { 606 TEE_Result res; 607 void *ctx; 608 609 res = crypto_hash_alloc_ctx(&ctx, TEE_FS_HTREE_HASH_ALG); 610 if (res != TEE_SUCCESS) 611 return res; 612 613 ht->root.id = 1; 614 ht->root.dirty = true; 615 616 res = calc_node_hash(&ht->root, &ht->imeta.meta, ctx, 617 ht->root.node.hash); 618 crypto_hash_free_ctx(ctx); 619 620 return res; 621 } 622 623 TEE_Result tee_fs_htree_open(bool create, uint8_t *hash, uint32_t min_counter, 624 const TEE_UUID *uuid, 625 const struct tee_fs_htree_storage *stor, 626 void *stor_aux, struct tee_fs_htree **ht_ret) 627 { 628 TEE_Result res; 629 struct tee_fs_htree *ht = calloc(1, sizeof(*ht)); 630 631 if (!ht) 632 return TEE_ERROR_OUT_OF_MEMORY; 633 634 ht->uuid = uuid; 635 ht->stor = stor; 636 ht->stor_aux = stor_aux; 637 638 if (create) { 639 const struct tee_fs_htree_image dummy_head = { 640 .counter = min_counter, 641 }; 642 643 res = crypto_rng_read(ht->fek, sizeof(ht->fek)); 644 if (res != TEE_SUCCESS) 645 goto out; 646 647 res = tee_fs_fek_crypt(ht->uuid, TEE_MODE_ENCRYPT, ht->fek, 648 sizeof(ht->fek), ht->head.enc_fek); 649 if (res != TEE_SUCCESS) 650 goto out; 651 652 res = init_root_node(ht); 653 if (res != TEE_SUCCESS) 654 goto out; 655 656 ht->dirty = true; 657 res = tee_fs_htree_sync_to_storage(&ht, hash, NULL); 658 if (res != TEE_SUCCESS) 659 goto out; 660 res = rpc_write_head(ht, 0, &dummy_head); 661 } else { 662 res = init_head_from_data(ht, hash, min_counter); 663 if (res != TEE_SUCCESS) 664 goto out; 665 666 res = verify_root(ht); 667 if (res != TEE_SUCCESS) 668 goto out; 669 670 res = init_tree_from_data(ht); 671 if (res != TEE_SUCCESS) 672 goto out; 673 674 res = verify_tree(ht); 675 } 676 out: 677 if (res == TEE_SUCCESS) 678 *ht_ret = ht; 679 else 680 tee_fs_htree_close(&ht); 681 return res; 682 } 683 684 struct tee_fs_htree_meta *tee_fs_htree_get_meta(struct tee_fs_htree *ht) 685 { 686 return &ht->imeta.meta; 687 } 688 689 void tee_fs_htree_meta_set_dirty(struct tee_fs_htree *ht) 690 { 691 ht->dirty = true; 692 ht->root.dirty = true; 693 } 694 695 static TEE_Result free_node(struct traverse_arg *targ __unused, 696 struct htree_node *node) 697 { 698 if (node->parent) 699 free(node); 700 return TEE_SUCCESS; 701 } 702 703 void tee_fs_htree_close(struct tee_fs_htree **ht) 704 { 705 if (!*ht) 706 return; 707 htree_traverse_post_order(*ht, free_node, NULL); 708 free(*ht); 709 *ht = NULL; 710 } 711 712 static TEE_Result htree_sync_node_to_storage(struct traverse_arg *targ, 713 struct htree_node *node) 714 { 715 TEE_Result res; 716 uint8_t vers; 717 struct tee_fs_htree_meta *meta = NULL; 718 719 /* 720 * The node can be dirty while the block isn't updated due to 721 * updated children, but if block is updated the node has to be 722 * dirty. 723 */ 724 assert(node->dirty >= node->block_updated); 725 726 if (!node->dirty) 727 return TEE_SUCCESS; 728 729 if (node->parent) { 730 uint32_t f = HTREE_NODE_COMMITTED_CHILD(node->id & 1); 731 732 node->parent->dirty = true; 733 node->parent->node.flags ^= f; 734 vers = !!(node->parent->node.flags & f); 735 } else { 736 /* 737 * Counter isn't updated yet, it's increased just before 738 * writing the header. 739 */ 740 vers = !(targ->ht->head.counter & 1); 741 meta = &targ->ht->imeta.meta; 742 } 743 744 res = calc_node_hash(node, meta, targ->arg, node->node.hash); 745 if (res != TEE_SUCCESS) 746 return res; 747 748 node->dirty = false; 749 node->block_updated = false; 750 751 return rpc_write_node(targ->ht, node->id, vers, &node->node); 752 } 753 754 static TEE_Result update_root(struct tee_fs_htree *ht) 755 { 756 TEE_Result res; 757 void *ctx; 758 759 ht->head.counter++; 760 761 res = authenc_init(&ctx, TEE_MODE_ENCRYPT, ht, NULL, sizeof(ht->imeta)); 762 if (res != TEE_SUCCESS) 763 return res; 764 765 return authenc_encrypt_final(ctx, ht->head.tag, &ht->imeta, 766 sizeof(ht->imeta), &ht->head.imeta); 767 } 768 769 TEE_Result tee_fs_htree_sync_to_storage(struct tee_fs_htree **ht_arg, 770 uint8_t *hash, uint32_t *counter) 771 { 772 TEE_Result res; 773 struct tee_fs_htree *ht = *ht_arg; 774 void *ctx; 775 776 if (!ht) 777 return TEE_ERROR_CORRUPT_OBJECT; 778 779 if (!ht->dirty) 780 return TEE_SUCCESS; 781 782 res = crypto_hash_alloc_ctx(&ctx, TEE_FS_HTREE_HASH_ALG); 783 if (res != TEE_SUCCESS) 784 return res; 785 786 res = htree_traverse_post_order(ht, htree_sync_node_to_storage, ctx); 787 if (res != TEE_SUCCESS) 788 goto out; 789 790 /* All the nodes are written to storage now. Time to update root. */ 791 res = update_root(ht); 792 if (res != TEE_SUCCESS) 793 goto out; 794 795 res = rpc_write_head(ht, ht->head.counter & 1, &ht->head); 796 if (res != TEE_SUCCESS) 797 goto out; 798 799 ht->dirty = false; 800 if (hash) 801 memcpy(hash, ht->root.node.hash, sizeof(ht->root.node.hash)); 802 if (counter) 803 *counter = ht->head.counter; 804 out: 805 crypto_hash_free_ctx(ctx); 806 if (res != TEE_SUCCESS) 807 tee_fs_htree_close(ht_arg); 808 return res; 809 } 810 811 static TEE_Result get_block_node(struct tee_fs_htree *ht, bool create, 812 size_t block_num, struct htree_node **node) 813 { 814 TEE_Result res; 815 struct htree_node *nd; 816 817 res = get_node(ht, create, BLOCK_NUM_TO_NODE_ID(block_num), &nd); 818 if (res == TEE_SUCCESS) 819 *node = nd; 820 821 return res; 822 } 823 824 TEE_Result tee_fs_htree_write_block(struct tee_fs_htree **ht_arg, 825 size_t block_num, const void *block) 826 { 827 struct tee_fs_htree *ht = *ht_arg; 828 TEE_Result res; 829 struct tee_fs_rpc_operation op; 830 struct htree_node *node = NULL; 831 uint8_t block_vers; 832 void *ctx; 833 void *enc_block; 834 835 if (!ht) 836 return TEE_ERROR_CORRUPT_OBJECT; 837 838 res = get_block_node(ht, true, block_num, &node); 839 if (res != TEE_SUCCESS) 840 goto out; 841 842 if (!node->block_updated) 843 node->node.flags ^= HTREE_NODE_COMMITTED_BLOCK; 844 845 block_vers = !!(node->node.flags & HTREE_NODE_COMMITTED_BLOCK); 846 res = ht->stor->rpc_write_init(ht->stor_aux, &op, 847 TEE_FS_HTREE_TYPE_BLOCK, block_num, 848 block_vers, &enc_block); 849 if (res != TEE_SUCCESS) 850 goto out; 851 852 res = authenc_init(&ctx, TEE_MODE_ENCRYPT, ht, &node->node, 853 ht->stor->block_size); 854 if (res != TEE_SUCCESS) 855 goto out; 856 res = authenc_encrypt_final(ctx, node->node.tag, block, 857 ht->stor->block_size, enc_block); 858 if (res != TEE_SUCCESS) 859 goto out; 860 861 res = ht->stor->rpc_write_final(&op); 862 if (res != TEE_SUCCESS) 863 goto out; 864 865 node->block_updated = true; 866 node->dirty = true; 867 ht->dirty = true; 868 out: 869 if (res != TEE_SUCCESS) 870 tee_fs_htree_close(ht_arg); 871 return res; 872 } 873 874 TEE_Result tee_fs_htree_read_block(struct tee_fs_htree **ht_arg, 875 size_t block_num, void *block) 876 { 877 struct tee_fs_htree *ht = *ht_arg; 878 TEE_Result res; 879 struct tee_fs_rpc_operation op; 880 struct htree_node *node; 881 uint8_t block_vers; 882 size_t len; 883 void *ctx; 884 void *enc_block; 885 886 if (!ht) 887 return TEE_ERROR_CORRUPT_OBJECT; 888 889 res = get_block_node(ht, false, block_num, &node); 890 if (res != TEE_SUCCESS) 891 goto out; 892 893 block_vers = !!(node->node.flags & HTREE_NODE_COMMITTED_BLOCK); 894 res = ht->stor->rpc_read_init(ht->stor_aux, &op, 895 TEE_FS_HTREE_TYPE_BLOCK, block_num, 896 block_vers, &enc_block); 897 if (res != TEE_SUCCESS) 898 goto out; 899 900 res = ht->stor->rpc_read_final(&op, &len); 901 if (res != TEE_SUCCESS) 902 goto out; 903 if (len != ht->stor->block_size) { 904 res = TEE_ERROR_CORRUPT_OBJECT; 905 goto out; 906 } 907 908 res = authenc_init(&ctx, TEE_MODE_DECRYPT, ht, &node->node, 909 ht->stor->block_size); 910 if (res != TEE_SUCCESS) 911 goto out; 912 913 res = authenc_decrypt_final(ctx, node->node.tag, enc_block, 914 ht->stor->block_size, block); 915 out: 916 if (res != TEE_SUCCESS) 917 tee_fs_htree_close(ht_arg); 918 return res; 919 } 920 921 TEE_Result tee_fs_htree_truncate(struct tee_fs_htree **ht_arg, size_t block_num) 922 { 923 struct tee_fs_htree *ht = *ht_arg; 924 size_t node_id = BLOCK_NUM_TO_NODE_ID(block_num); 925 struct htree_node *node; 926 927 if (!ht) 928 return TEE_ERROR_CORRUPT_OBJECT; 929 930 while (node_id < ht->imeta.max_node_id) { 931 node = find_closest_node(ht, ht->imeta.max_node_id); 932 assert(node && node->id == ht->imeta.max_node_id); 933 assert(!node->child[0] && !node->child[1]); 934 assert(node->parent); 935 assert(node->parent->child[node->id & 1] == node); 936 node->parent->child[node->id & 1] = NULL; 937 free(node); 938 ht->imeta.max_node_id--; 939 ht->dirty = true; 940 } 941 942 return TEE_SUCCESS; 943 } 944