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