1 // SPDX-License-Identifier: BSD-2-Clause 2 /* 3 * Copyright (c) 2017, Linaro Limited 4 */ 5 6 #include <assert.h> 7 #include <crypto/crypto.h> 8 #include <initcall.h> 9 #include <kernel/tee_common_otp.h> 10 #include <optee_msg_supplicant.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) 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_SECURITY; 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 ht->root.id = 1; 365 366 return TEE_SUCCESS; 367 } 368 369 static TEE_Result init_tree_from_data(struct tee_fs_htree *ht) 370 { 371 TEE_Result res; 372 struct tee_fs_htree_node_image node_image; 373 struct htree_node *node; 374 struct htree_node *nc; 375 size_t committed_version; 376 size_t node_id = 2; 377 378 while (node_id <= ht->imeta.max_node_id) { 379 node = find_node(ht, node_id >> 1); 380 if (!node) 381 return TEE_ERROR_GENERIC; 382 committed_version = !!(node->node.flags & 383 HTREE_NODE_COMMITTED_CHILD(node_id & 1)); 384 385 res = rpc_read_node(ht, node_id, committed_version, 386 &node_image); 387 if (res != TEE_SUCCESS) 388 return res; 389 390 res = get_node(ht, true, node_id, &nc); 391 if (res != TEE_SUCCESS) 392 return res; 393 nc->node = node_image; 394 node_id++; 395 } 396 397 return TEE_SUCCESS; 398 } 399 400 static TEE_Result calc_node_hash(struct htree_node *node, void *ctx, 401 uint8_t *digest) 402 { 403 TEE_Result res; 404 uint32_t alg = TEE_FS_HTREE_HASH_ALG; 405 uint8_t *ndata = (uint8_t *)&node->node + sizeof(node->node.hash); 406 size_t nsize = sizeof(node->node) - sizeof(node->node.hash); 407 408 res = crypto_hash_init(ctx, alg); 409 if (res != TEE_SUCCESS) 410 return res; 411 412 res = crypto_hash_update(ctx, alg, ndata, nsize); 413 if (res != TEE_SUCCESS) 414 return res; 415 416 if (node->child[0]) { 417 res = crypto_hash_update(ctx, alg, node->child[0]->node.hash, 418 sizeof(node->child[0]->node.hash)); 419 if (res != TEE_SUCCESS) 420 return res; 421 } 422 423 if (node->child[1]) { 424 res = crypto_hash_update(ctx, alg, node->child[1]->node.hash, 425 sizeof(node->child[1]->node.hash)); 426 if (res != TEE_SUCCESS) 427 return res; 428 } 429 430 return crypto_hash_final(ctx, alg, digest, TEE_FS_HTREE_HASH_SIZE); 431 } 432 433 static TEE_Result authenc_init(void **ctx_ret, TEE_OperationMode mode, 434 struct tee_fs_htree *ht, 435 struct tee_fs_htree_node_image *ni, 436 size_t payload_len) 437 { 438 TEE_Result res = TEE_SUCCESS; 439 const uint32_t alg = TEE_FS_HTREE_AUTH_ENC_ALG; 440 uint8_t *ctx; 441 size_t ctx_size; 442 size_t aad_len = TEE_FS_HTREE_FEK_SIZE + TEE_FS_HTREE_IV_SIZE; 443 uint8_t *iv; 444 445 if (ni) { 446 iv = ni->iv; 447 } else { 448 iv = ht->head.iv; 449 aad_len += TEE_FS_HTREE_HASH_SIZE + sizeof(ht->head.counter); 450 } 451 452 if (mode == TEE_MODE_ENCRYPT) { 453 res = crypto_rng_read(iv, TEE_FS_HTREE_IV_SIZE); 454 if (res != TEE_SUCCESS) 455 return res; 456 } 457 458 res = crypto_authenc_get_ctx_size(alg, &ctx_size); 459 if (res != TEE_SUCCESS) 460 return res; 461 462 ctx = malloc(ctx_size); 463 if (!ctx) { 464 EMSG("request memory size %zu failed", ctx_size); 465 return TEE_ERROR_OUT_OF_MEMORY; 466 } 467 468 res = crypto_authenc_init(ctx, alg, mode, ht->fek, 469 TEE_FS_HTREE_FEK_SIZE, iv, 470 TEE_FS_HTREE_IV_SIZE, TEE_FS_HTREE_TAG_SIZE, 471 aad_len, payload_len); 472 if (res != TEE_SUCCESS) 473 goto exit; 474 475 if (!ni) { 476 res = crypto_authenc_update_aad(ctx, alg, mode, 477 ht->root.node.hash, 478 TEE_FS_HTREE_FEK_SIZE); 479 if (res != TEE_SUCCESS) 480 goto exit; 481 482 res = crypto_authenc_update_aad(ctx, alg, mode, 483 (void *)&ht->head.counter, 484 sizeof(ht->head.counter)); 485 if (res != TEE_SUCCESS) 486 goto exit; 487 } 488 489 res = crypto_authenc_update_aad(ctx, alg, mode, ht->head.enc_fek, 490 TEE_FS_HTREE_FEK_SIZE); 491 if (res != TEE_SUCCESS) 492 goto exit; 493 494 res = crypto_authenc_update_aad(ctx, alg, mode, iv, 495 TEE_FS_HTREE_IV_SIZE); 496 497 exit: 498 if (res == TEE_SUCCESS) 499 *ctx_ret = ctx; 500 else 501 free(ctx); 502 503 return res; 504 } 505 506 static TEE_Result authenc_decrypt_final(void *ctx, const uint8_t *tag, 507 const void *crypt, size_t len, 508 void *plain) 509 { 510 TEE_Result res; 511 size_t out_size = len; 512 513 res = crypto_authenc_dec_final(ctx, TEE_FS_HTREE_AUTH_ENC_ALG, crypt, 514 len, plain, &out_size, tag, 515 TEE_FS_HTREE_TAG_SIZE); 516 crypto_authenc_final(ctx, TEE_FS_HTREE_AUTH_ENC_ALG); 517 free(ctx); 518 519 if (res == TEE_SUCCESS && out_size != len) 520 return TEE_ERROR_GENERIC; 521 if (res == TEE_ERROR_MAC_INVALID) 522 return TEE_ERROR_CORRUPT_OBJECT; 523 524 return res; 525 } 526 527 static TEE_Result authenc_encrypt_final(void *ctx, uint8_t *tag, 528 const void *plain, size_t len, 529 void *crypt) 530 { 531 TEE_Result res; 532 size_t out_size = len; 533 size_t out_tag_size = TEE_FS_HTREE_TAG_SIZE; 534 535 res = crypto_authenc_enc_final(ctx, TEE_FS_HTREE_AUTH_ENC_ALG, plain, 536 len, crypt, &out_size, tag, 537 &out_tag_size); 538 crypto_authenc_final(ctx, TEE_FS_HTREE_AUTH_ENC_ALG); 539 free(ctx); 540 541 if (res == TEE_SUCCESS && 542 (out_size != len || out_tag_size != TEE_FS_HTREE_TAG_SIZE)) 543 return TEE_ERROR_GENERIC; 544 545 return res; 546 } 547 548 static TEE_Result verify_root(struct tee_fs_htree *ht) 549 { 550 TEE_Result res; 551 void *ctx; 552 553 res = tee_fs_fek_crypt(ht->uuid, TEE_MODE_DECRYPT, ht->head.enc_fek, 554 sizeof(ht->fek), ht->fek); 555 if (res != TEE_SUCCESS) 556 return res; 557 558 res = authenc_init(&ctx, TEE_MODE_DECRYPT, ht, NULL, sizeof(ht->imeta)); 559 if (res != TEE_SUCCESS) 560 return res; 561 562 return authenc_decrypt_final(ctx, ht->head.tag, ht->head.imeta, 563 sizeof(ht->imeta), &ht->imeta); 564 } 565 566 static TEE_Result verify_node(struct traverse_arg *targ, 567 struct htree_node *node) 568 { 569 void *ctx = targ->arg; 570 TEE_Result res; 571 uint8_t digest[TEE_FS_HTREE_HASH_SIZE]; 572 573 res = calc_node_hash(node, ctx, digest); 574 if (res == TEE_SUCCESS && 575 buf_compare_ct(digest, node->node.hash, sizeof(digest))) 576 return TEE_ERROR_CORRUPT_OBJECT; 577 578 return res; 579 } 580 581 static TEE_Result verify_tree(struct tee_fs_htree *ht) 582 { 583 TEE_Result res; 584 size_t size; 585 void *ctx; 586 587 res = crypto_hash_get_ctx_size(TEE_FS_HTREE_HASH_ALG, &size); 588 if (res != TEE_SUCCESS) 589 return res; 590 591 ctx = malloc(size); 592 if (!ctx) 593 return TEE_ERROR_OUT_OF_MEMORY; 594 595 res = htree_traverse_post_order(ht, verify_node, ctx); 596 free(ctx); 597 598 return res; 599 } 600 601 static TEE_Result init_root_node(struct tee_fs_htree *ht) 602 { 603 TEE_Result res; 604 size_t size; 605 void *ctx; 606 607 res = crypto_hash_get_ctx_size(TEE_FS_HTREE_HASH_ALG, &size); 608 if (res != TEE_SUCCESS) 609 return res; 610 ctx = malloc(size); 611 if (!ctx) 612 return TEE_ERROR_OUT_OF_MEMORY; 613 614 ht->root.id = 1; 615 ht->root.dirty = true; 616 617 res = calc_node_hash(&ht->root, ctx, ht->root.node.hash); 618 free(ctx); 619 620 return res; 621 } 622 623 TEE_Result tee_fs_htree_open(bool create, uint8_t *hash, const TEE_UUID *uuid, 624 const struct tee_fs_htree_storage *stor, 625 void *stor_aux, struct tee_fs_htree **ht_ret) 626 { 627 TEE_Result res; 628 struct tee_fs_htree *ht = calloc(1, sizeof(*ht)); 629 630 if (!ht) 631 return TEE_ERROR_OUT_OF_MEMORY; 632 633 ht->uuid = uuid; 634 ht->stor = stor; 635 ht->stor_aux = stor_aux; 636 637 if (create) { 638 const struct tee_fs_htree_image dummy_head = { .counter = 0 }; 639 640 res = crypto_rng_read(ht->fek, sizeof(ht->fek)); 641 if (res != TEE_SUCCESS) 642 goto out; 643 644 res = tee_fs_fek_crypt(ht->uuid, TEE_MODE_ENCRYPT, ht->fek, 645 sizeof(ht->fek), ht->head.enc_fek); 646 if (res != TEE_SUCCESS) 647 goto out; 648 649 res = init_root_node(ht); 650 if (res != TEE_SUCCESS) 651 goto out; 652 653 ht->dirty = true; 654 res = tee_fs_htree_sync_to_storage(&ht, hash); 655 if (res != TEE_SUCCESS) 656 goto out; 657 res = rpc_write_head(ht, 0, &dummy_head); 658 } else { 659 res = init_head_from_data(ht, hash); 660 if (res != TEE_SUCCESS) 661 goto out; 662 663 res = verify_root(ht); 664 if (res != TEE_SUCCESS) 665 goto out; 666 667 res = init_tree_from_data(ht); 668 if (res != TEE_SUCCESS) 669 goto out; 670 671 res = verify_tree(ht); 672 } 673 out: 674 if (res == TEE_SUCCESS) 675 *ht_ret = ht; 676 else 677 tee_fs_htree_close(&ht); 678 return res; 679 } 680 681 struct tee_fs_htree_meta *tee_fs_htree_get_meta(struct tee_fs_htree *ht) 682 { 683 return &ht->imeta.meta; 684 } 685 686 static TEE_Result free_node(struct traverse_arg *targ __unused, 687 struct htree_node *node) 688 { 689 if (node->parent) 690 free(node); 691 return TEE_SUCCESS; 692 } 693 694 void tee_fs_htree_close(struct tee_fs_htree **ht) 695 { 696 if (!*ht) 697 return; 698 htree_traverse_post_order(*ht, free_node, NULL); 699 free(*ht); 700 *ht = NULL; 701 } 702 703 static TEE_Result htree_sync_node_to_storage(struct traverse_arg *targ, 704 struct htree_node *node) 705 { 706 TEE_Result res; 707 uint8_t vers; 708 709 /* 710 * The node can be dirty while the block isn't updated due to 711 * updated children, but if block is updated the node has to be 712 * dirty. 713 */ 714 assert(node->dirty >= node->block_updated); 715 716 if (!node->dirty) 717 return TEE_SUCCESS; 718 719 if (node->parent) { 720 uint32_t f = HTREE_NODE_COMMITTED_CHILD(node->id & 1); 721 722 node->parent->dirty = true; 723 node->parent->node.flags ^= f; 724 vers = !!(node->parent->node.flags & f); 725 } else { 726 /* 727 * Counter isn't updated yet, it's increased just before 728 * writing the header. 729 */ 730 vers = !(targ->ht->head.counter & 1); 731 } 732 733 res = calc_node_hash(node, targ->arg, node->node.hash); 734 if (res != TEE_SUCCESS) 735 return res; 736 737 node->dirty = false; 738 node->block_updated = false; 739 740 return rpc_write_node(targ->ht, node->id, vers, &node->node); 741 } 742 743 static TEE_Result update_root(struct tee_fs_htree *ht) 744 { 745 TEE_Result res; 746 void *ctx; 747 748 ht->head.counter++; 749 750 res = authenc_init(&ctx, TEE_MODE_ENCRYPT, ht, NULL, sizeof(ht->imeta)); 751 if (res != TEE_SUCCESS) 752 return res; 753 754 return authenc_encrypt_final(ctx, ht->head.tag, &ht->imeta, 755 sizeof(ht->imeta), &ht->head.imeta); 756 } 757 758 TEE_Result tee_fs_htree_sync_to_storage(struct tee_fs_htree **ht_arg, 759 uint8_t *hash) 760 { 761 TEE_Result res; 762 struct tee_fs_htree *ht = *ht_arg; 763 size_t size; 764 void *ctx; 765 766 if (!ht) 767 return TEE_ERROR_CORRUPT_OBJECT; 768 769 if (!ht->dirty) 770 return TEE_SUCCESS; 771 772 res = crypto_hash_get_ctx_size(TEE_FS_HTREE_HASH_ALG, &size); 773 if (res != TEE_SUCCESS) 774 return res; 775 ctx = malloc(size); 776 if (!ctx) 777 return TEE_ERROR_OUT_OF_MEMORY; 778 779 res = htree_traverse_post_order(ht, htree_sync_node_to_storage, ctx); 780 if (res != TEE_SUCCESS) 781 goto out; 782 783 /* All the nodes are written to storage now. Time to update root. */ 784 res = update_root(ht); 785 if (res != TEE_SUCCESS) 786 goto out; 787 788 res = rpc_write_head(ht, ht->head.counter & 1, &ht->head); 789 if (res != TEE_SUCCESS) 790 goto out; 791 792 ht->dirty = false; 793 if (hash) 794 memcpy(hash, ht->root.node.hash, sizeof(ht->root.node.hash)); 795 out: 796 free(ctx); 797 if (res != TEE_SUCCESS) 798 tee_fs_htree_close(ht_arg); 799 return res; 800 } 801 802 static TEE_Result get_block_node(struct tee_fs_htree *ht, bool create, 803 size_t block_num, struct htree_node **node) 804 { 805 TEE_Result res; 806 struct htree_node *nd; 807 808 res = get_node(ht, create, BLOCK_NUM_TO_NODE_ID(block_num), &nd); 809 if (res == TEE_SUCCESS) 810 *node = nd; 811 812 return res; 813 } 814 815 TEE_Result tee_fs_htree_write_block(struct tee_fs_htree **ht_arg, 816 size_t block_num, const void *block) 817 { 818 struct tee_fs_htree *ht = *ht_arg; 819 TEE_Result res; 820 struct tee_fs_rpc_operation op; 821 struct htree_node *node = NULL; 822 uint8_t block_vers; 823 void *ctx; 824 void *enc_block; 825 826 if (!ht) 827 return TEE_ERROR_CORRUPT_OBJECT; 828 829 res = get_block_node(ht, true, block_num, &node); 830 if (res != TEE_SUCCESS) 831 goto out; 832 833 if (!node->block_updated) 834 node->node.flags ^= HTREE_NODE_COMMITTED_BLOCK; 835 836 block_vers = !!(node->node.flags & HTREE_NODE_COMMITTED_BLOCK); 837 res = ht->stor->rpc_write_init(ht->stor_aux, &op, 838 TEE_FS_HTREE_TYPE_BLOCK, block_num, 839 block_vers, &enc_block); 840 if (res != TEE_SUCCESS) 841 goto out; 842 843 res = authenc_init(&ctx, TEE_MODE_ENCRYPT, ht, &node->node, 844 ht->stor->block_size); 845 if (res != TEE_SUCCESS) 846 goto out; 847 res = authenc_encrypt_final(ctx, node->node.tag, block, 848 ht->stor->block_size, enc_block); 849 if (res != TEE_SUCCESS) 850 goto out; 851 852 res = ht->stor->rpc_write_final(&op); 853 if (res != TEE_SUCCESS) 854 goto out; 855 856 node->block_updated = true; 857 node->dirty = true; 858 ht->dirty = true; 859 out: 860 if (res != TEE_SUCCESS) 861 tee_fs_htree_close(ht_arg); 862 return res; 863 } 864 865 TEE_Result tee_fs_htree_read_block(struct tee_fs_htree **ht_arg, 866 size_t block_num, void *block) 867 { 868 struct tee_fs_htree *ht = *ht_arg; 869 TEE_Result res; 870 struct tee_fs_rpc_operation op; 871 struct htree_node *node; 872 uint8_t block_vers; 873 size_t len; 874 void *ctx; 875 void *enc_block; 876 877 if (!ht) 878 return TEE_ERROR_CORRUPT_OBJECT; 879 880 res = get_block_node(ht, false, block_num, &node); 881 if (res != TEE_SUCCESS) 882 goto out; 883 884 block_vers = !!(node->node.flags & HTREE_NODE_COMMITTED_BLOCK); 885 res = ht->stor->rpc_read_init(ht->stor_aux, &op, 886 TEE_FS_HTREE_TYPE_BLOCK, block_num, 887 block_vers, &enc_block); 888 if (res != TEE_SUCCESS) 889 goto out; 890 891 res = ht->stor->rpc_read_final(&op, &len); 892 if (res != TEE_SUCCESS) 893 goto out; 894 if (len != ht->stor->block_size) { 895 res = TEE_ERROR_CORRUPT_OBJECT; 896 goto out; 897 } 898 899 res = authenc_init(&ctx, TEE_MODE_DECRYPT, ht, &node->node, 900 ht->stor->block_size); 901 if (res != TEE_SUCCESS) 902 goto out; 903 904 res = authenc_decrypt_final(ctx, node->node.tag, enc_block, 905 ht->stor->block_size, block); 906 out: 907 if (res != TEE_SUCCESS) 908 tee_fs_htree_close(ht_arg); 909 return res; 910 } 911 912 TEE_Result tee_fs_htree_truncate(struct tee_fs_htree **ht_arg, size_t block_num) 913 { 914 struct tee_fs_htree *ht = *ht_arg; 915 size_t node_id = BLOCK_NUM_TO_NODE_ID(block_num); 916 struct htree_node *node; 917 918 if (!ht) 919 return TEE_ERROR_CORRUPT_OBJECT; 920 921 while (node_id < ht->imeta.max_node_id) { 922 node = find_closest_node(ht, ht->imeta.max_node_id); 923 assert(node && node->id == ht->imeta.max_node_id); 924 assert(!node->child[0] && !node->child[1]); 925 assert(node->parent); 926 assert(node->parent->child[node->id & 1] == node); 927 node->parent->child[node->id & 1] = NULL; 928 free(node); 929 ht->imeta.max_node_id--; 930 ht->dirty = true; 931 } 932 933 return TEE_SUCCESS; 934 } 935