1 /* 2 * Copyright (c) 2017, Linaro Limited 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, 9 * this list of conditions and the following disclaimer. 10 * 11 * 2. Redistributions in binary form must reproduce the above copyright notice, 12 * this list of conditions and the following disclaimer in the documentation 13 * and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 19 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25 * POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include <assert.h> 29 #include <initcall.h> 30 #include <kernel/tee_common_otp.h> 31 #include <optee_msg_supplicant.h> 32 #include <stdlib.h> 33 #include <string_ext.h> 34 #include <string.h> 35 #include <tee/fs_htree.h> 36 #include <tee/tee_cryp_provider.h> 37 #include <tee/tee_fs_key_manager.h> 38 #include <tee/tee_fs_rpc.h> 39 #include <utee_defines.h> 40 #include <util.h> 41 42 #define TEE_FS_HTREE_CHIP_ID_SIZE 32 43 #define TEE_FS_HTREE_HASH_ALG TEE_ALG_SHA256 44 #define TEE_FS_HTREE_TSK_SIZE TEE_FS_HTREE_HASH_SIZE 45 #define TEE_FS_HTREE_ENC_ALG TEE_ALG_AES_ECB_NOPAD 46 #define TEE_FS_HTREE_ENC_SIZE TEE_AES_BLOCK_SIZE 47 #define TEE_FS_HTREE_SSK_SIZE TEE_FS_HTREE_HASH_SIZE 48 49 #define TEE_FS_HTREE_AUTH_ENC_ALG TEE_ALG_AES_GCM 50 #define TEE_FS_HTREE_HMAC_ALG TEE_ALG_HMAC_SHA256 51 52 #define BLOCK_NUM_TO_NODE_ID(num) ((num) + 1) 53 54 #define NODE_ID_TO_BLOCK_NUM(id) ((id) - 1) 55 56 /* 57 * The hash tree is implemented as a binary tree with the purpose to ensure 58 * integrity of the data in the nodes. The data in the nodes their turn 59 * provides both integrity and confidentiality of the data blocks. 60 * 61 * The hash tree is saved in a file as: 62 * +----------------------------+ 63 * | htree_image.0 | 64 * | htree_image.1 | 65 * +----------------------------+ 66 * | htree_node_image.1.0 | 67 * | htree_node_image.1.1 | 68 * +----------------------------+ 69 * | htree_node_image.2.0 | 70 * | htree_node_image.2.1 | 71 * +----------------------------+ 72 * | htree_node_image.3.0 | 73 * | htree_node_image.3.1 | 74 * +----------------------------+ 75 * | htree_node_image.4.0 | 76 * | htree_node_image.4.1 | 77 * +----------------------------+ 78 * ... 79 * 80 * htree_image is the header of the file, there's two instances of it. One 81 * which is committed and the other is used when updating the file. Which 82 * is committed is indicated by the "counter" field, the one with the 83 * largest value is selected. 84 * 85 * htree_node_image is a node in the hash tree, each node has two instances 86 * which is committed is decided by the parent node .flag bit 87 * HTREE_NODE_COMMITTED_CHILD. Which version is the committed version of 88 * node 1 is determined by the by the lowest bit of the counter field in 89 * the header. 90 * 91 * Note that nodes start counting at 1 while blocks at 0, this means that 92 * block 0 is represented by node 1. 93 * 94 * Where different elements are stored in the file is managed by the file 95 * system. In the case of SQL FS the version of the node/block is ignored 96 * as the atomic update is finalized with a call to 97 * tee_fs_rpc_end_transaction(). 98 */ 99 100 #define HTREE_NODE_COMMITTED_BLOCK BIT32(0) 101 /* n is 0 or 1 */ 102 #define HTREE_NODE_COMMITTED_CHILD(n) BIT32(1 + (n)) 103 104 struct htree_node { 105 size_t id; 106 bool dirty; 107 bool block_updated; 108 struct tee_fs_htree_node_image node; 109 struct htree_node *parent; 110 struct htree_node *child[2]; 111 }; 112 113 struct tee_fs_htree { 114 struct htree_node root; 115 struct tee_fs_htree_image head; 116 uint8_t fek[TEE_FS_HTREE_FEK_SIZE]; 117 struct tee_fs_htree_imeta imeta; 118 bool dirty; 119 const struct tee_fs_htree_storage *stor; 120 void *stor_aux; 121 }; 122 123 struct traverse_arg; 124 typedef TEE_Result (*traverse_cb_t)(struct traverse_arg *targ, 125 struct htree_node *node); 126 struct traverse_arg { 127 struct tee_fs_htree *ht; 128 traverse_cb_t cb; 129 void *arg; 130 }; 131 132 static TEE_Result rpc_read(struct tee_fs_htree *ht, enum tee_fs_htree_type type, 133 size_t idx, size_t vers, void *data, size_t dlen) 134 { 135 TEE_Result res; 136 struct tee_fs_rpc_operation op; 137 size_t bytes; 138 void *p; 139 140 res = ht->stor->rpc_read_init(ht->stor_aux, &op, type, idx, vers, &p); 141 if (res != TEE_SUCCESS) 142 return res; 143 144 res = ht->stor->rpc_read_final(&op, &bytes); 145 if (res != TEE_SUCCESS) 146 return res; 147 148 if (bytes != dlen) 149 return TEE_ERROR_CORRUPT_OBJECT; 150 151 memcpy(data, p, dlen); 152 return TEE_SUCCESS; 153 } 154 155 static TEE_Result rpc_read_head(struct tee_fs_htree *ht, size_t vers, 156 struct tee_fs_htree_image *head) 157 { 158 return rpc_read(ht, TEE_FS_HTREE_TYPE_HEAD, 0, vers, 159 head, sizeof(*head)); 160 } 161 162 static TEE_Result rpc_read_node(struct tee_fs_htree *ht, size_t node_id, 163 size_t vers, 164 struct tee_fs_htree_node_image *node) 165 { 166 return rpc_read(ht, TEE_FS_HTREE_TYPE_NODE, node_id - 1, vers, 167 node, sizeof(*node)); 168 } 169 170 static TEE_Result rpc_write(struct tee_fs_htree *ht, 171 enum tee_fs_htree_type type, size_t idx, 172 size_t vers, const void *data, size_t dlen) 173 { 174 TEE_Result res; 175 struct tee_fs_rpc_operation op; 176 void *p; 177 178 res = ht->stor->rpc_write_init(ht->stor_aux, &op, type, idx, vers, &p); 179 if (res != TEE_SUCCESS) 180 return res; 181 182 memcpy(p, data, dlen); 183 return ht->stor->rpc_write_final(&op); 184 } 185 186 static TEE_Result rpc_write_head(struct tee_fs_htree *ht, size_t vers, 187 const struct tee_fs_htree_image *head) 188 { 189 return rpc_write(ht, TEE_FS_HTREE_TYPE_HEAD, 0, vers, 190 head, sizeof(*head)); 191 } 192 193 static TEE_Result rpc_write_node(struct tee_fs_htree *ht, size_t node_id, 194 size_t vers, 195 const struct tee_fs_htree_node_image *node) 196 { 197 return rpc_write(ht, TEE_FS_HTREE_TYPE_NODE, node_id - 1, vers, 198 node, sizeof(*node)); 199 } 200 201 static TEE_Result traverse_post_order(struct traverse_arg *targ, 202 struct htree_node *node) 203 { 204 TEE_Result res; 205 206 /* 207 * This function is recursing but not very deep, only with Log(N) 208 * maximum depth. 209 */ 210 211 if (!node) 212 return TEE_SUCCESS; 213 214 res = traverse_post_order(targ, node->child[0]); 215 if (res != TEE_SUCCESS) 216 return res; 217 218 res = traverse_post_order(targ, node->child[1]); 219 if (res != TEE_SUCCESS) 220 return res; 221 222 return targ->cb(targ, node); 223 } 224 225 static TEE_Result htree_traverse_post_order(struct tee_fs_htree *ht, 226 traverse_cb_t cb, void *arg) 227 { 228 struct traverse_arg targ = { ht, cb, arg }; 229 230 return traverse_post_order(&targ, &ht->root); 231 } 232 233 static size_t node_id_to_level(size_t node_id) 234 { 235 assert(node_id && node_id < UINT_MAX); 236 /* Calculate level of the node, root node (1) has level 1 */ 237 return sizeof(unsigned int) * 8 - __builtin_clz(node_id); 238 } 239 240 static struct htree_node *find_closest_node(struct tee_fs_htree *ht, 241 size_t node_id) 242 { 243 struct htree_node *node = &ht->root; 244 size_t level = node_id_to_level(node_id); 245 size_t n; 246 247 /* n = 1 because root node is level 1 */ 248 for (n = 1; n < level; n++) { 249 struct htree_node *child; 250 size_t bit_idx; 251 252 /* 253 * The difference between levels of the current node and 254 * the node we're looking for tells which bit decides 255 * direction in the tree. 256 * 257 * As the first bit has index 0 we'll subtract 1 258 */ 259 bit_idx = level - n - 1; 260 child = node->child[((node_id >> bit_idx) & 1)]; 261 if (!child) 262 return node; 263 node = child; 264 } 265 266 return node; 267 } 268 269 static struct htree_node *find_node(struct tee_fs_htree *ht, size_t node_id) 270 { 271 struct htree_node *node = find_closest_node(ht, node_id); 272 273 if (node && node->id == node_id) 274 return node; 275 return NULL; 276 } 277 278 static TEE_Result get_node(struct tee_fs_htree *ht, bool create, 279 size_t node_id, struct htree_node **node_ret) 280 { 281 struct htree_node *node; 282 struct htree_node *nc; 283 size_t n; 284 285 node = find_closest_node(ht, node_id); 286 if (!node) 287 return TEE_ERROR_GENERIC; 288 if (node->id == node_id) 289 goto ret_node; 290 291 /* 292 * Trying to read beyond end of file should be caught earlier than 293 * here. 294 */ 295 if (!create) 296 return TEE_ERROR_GENERIC; 297 298 /* 299 * Add missing nodes, some nodes may already be there. When we've 300 * processed the range all nodes up to node_id will be in the tree. 301 */ 302 for (n = node->id + 1; n <= node_id; n++) { 303 node = find_closest_node(ht, n); 304 if (node->id == n) 305 continue; 306 /* Node id n should be a child of node */ 307 assert((n >> 1) == node->id); 308 assert(!node->child[n & 1]); 309 310 nc = calloc(1, sizeof(*nc)); 311 if (!nc) 312 return TEE_ERROR_OUT_OF_MEMORY; 313 nc->id = n; 314 nc->parent = node; 315 node->child[n & 1] = nc; 316 node = nc; 317 } 318 319 if (node->id > ht->imeta.max_node_id) 320 ht->imeta.max_node_id = node->id; 321 322 ret_node: 323 *node_ret = node; 324 return TEE_SUCCESS; 325 } 326 327 static int get_idx_from_counter(uint32_t counter0, uint32_t counter1) 328 { 329 if (!(counter0 & 1)) { 330 if (!(counter1 & 1)) 331 return 0; 332 if (counter0 > counter1) 333 return 0; 334 else 335 return 1; 336 } 337 338 if (counter1 & 1) 339 return 1; 340 else 341 return -1; 342 } 343 344 static TEE_Result init_head_from_data(struct tee_fs_htree *ht, 345 const uint8_t *hash) 346 { 347 TEE_Result res; 348 int idx; 349 350 if (hash) { 351 for (idx = 0;; idx++) { 352 res = rpc_read_node(ht, 1, idx, &ht->root.node); 353 if (res != TEE_SUCCESS) 354 return res; 355 356 if (!memcmp(ht->root.node.hash, hash, 357 sizeof(ht->root.node.hash))) { 358 res = rpc_read_head(ht, idx, &ht->head); 359 if (res != TEE_SUCCESS) 360 return res; 361 break; 362 } 363 364 if (idx) 365 return TEE_ERROR_SECURITY; 366 } 367 } else { 368 struct tee_fs_htree_image head[2]; 369 370 for (idx = 0; idx < 2; idx++) { 371 res = rpc_read_head(ht, idx, head + idx); 372 if (res != TEE_SUCCESS) 373 return res; 374 } 375 376 idx = get_idx_from_counter(head[0].counter, head[1].counter); 377 if (idx < 0) 378 return TEE_ERROR_SECURITY; 379 380 res = rpc_read_node(ht, 1, idx, &ht->root.node); 381 if (res != TEE_SUCCESS) 382 return res; 383 384 ht->head = head[idx]; 385 } 386 387 ht->root.id = 1; 388 389 return TEE_SUCCESS; 390 } 391 392 static TEE_Result init_tree_from_data(struct tee_fs_htree *ht) 393 { 394 TEE_Result res; 395 struct tee_fs_htree_node_image node_image; 396 struct htree_node *node; 397 struct htree_node *nc; 398 size_t committed_version; 399 size_t node_id = 2; 400 401 while (node_id <= ht->imeta.max_node_id) { 402 node = find_node(ht, node_id >> 1); 403 if (!node) 404 return TEE_ERROR_GENERIC; 405 committed_version = !!(node->node.flags & 406 HTREE_NODE_COMMITTED_CHILD(node_id & 1)); 407 408 res = rpc_read_node(ht, node_id, committed_version, 409 &node_image); 410 if (res != TEE_SUCCESS) 411 return res; 412 413 res = get_node(ht, true, node_id, &nc); 414 if (res != TEE_SUCCESS) 415 return res; 416 nc->node = node_image; 417 node_id++; 418 } 419 420 return TEE_SUCCESS; 421 } 422 423 static TEE_Result calc_node_hash(struct htree_node *node, void *ctx, 424 uint8_t *digest) 425 { 426 TEE_Result res; 427 uint32_t alg = TEE_FS_HTREE_HASH_ALG; 428 uint8_t *ndata = (uint8_t *)&node->node + sizeof(node->node.hash); 429 size_t nsize = sizeof(node->node) - sizeof(node->node.hash); 430 431 res = crypto_ops.hash.init(ctx, alg); 432 if (res != TEE_SUCCESS) 433 return res; 434 435 res = crypto_ops.hash.update(ctx, alg, ndata, nsize); 436 if (res != TEE_SUCCESS) 437 return res; 438 439 if (node->child[0]) { 440 res = crypto_ops.hash.update(ctx, alg, 441 node->child[0]->node.hash, 442 sizeof(node->child[0]->node.hash)); 443 if (res != TEE_SUCCESS) 444 return res; 445 } 446 447 if (node->child[1]) { 448 res = crypto_ops.hash.update(ctx, alg, 449 node->child[1]->node.hash, 450 sizeof(node->child[1]->node.hash)); 451 if (res != TEE_SUCCESS) 452 return res; 453 } 454 455 return crypto_ops.hash.final(ctx, alg, digest, TEE_FS_HTREE_HASH_SIZE); 456 } 457 458 static TEE_Result authenc_init(void **ctx_ret, TEE_OperationMode mode, 459 struct tee_fs_htree *ht, 460 struct tee_fs_htree_node_image *ni, 461 size_t payload_len) 462 { 463 TEE_Result res = TEE_SUCCESS; 464 const uint32_t alg = TEE_FS_HTREE_AUTH_ENC_ALG; 465 uint8_t *ctx; 466 size_t ctx_size; 467 size_t aad_len = TEE_FS_HTREE_FEK_SIZE + TEE_FS_HTREE_IV_SIZE; 468 uint8_t *iv; 469 470 if (ni) { 471 iv = ni->iv; 472 } else { 473 iv = ht->head.iv; 474 aad_len += TEE_FS_HTREE_HASH_SIZE + sizeof(ht->head.counter); 475 } 476 477 if (mode == TEE_MODE_ENCRYPT) { 478 res = crypto_ops.prng.read(iv, TEE_FS_HTREE_IV_SIZE); 479 if (res != TEE_SUCCESS) 480 return res; 481 } 482 483 res = crypto_ops.authenc.get_ctx_size(alg, &ctx_size); 484 if (res != TEE_SUCCESS) 485 return res; 486 487 ctx = malloc(ctx_size); 488 if (!ctx) { 489 EMSG("request memory size %zu failed", ctx_size); 490 return TEE_ERROR_OUT_OF_MEMORY; 491 } 492 493 res = crypto_ops.authenc.init(ctx, alg, mode, 494 ht->fek, TEE_FS_HTREE_FEK_SIZE, 495 iv, TEE_FS_HTREE_IV_SIZE, 496 TEE_FS_HTREE_TAG_SIZE, aad_len, 497 payload_len); 498 if (res != TEE_SUCCESS) 499 goto exit; 500 501 if (!ni) { 502 res = crypto_ops.authenc.update_aad(ctx, alg, mode, 503 ht->root.node.hash, 504 TEE_FS_HTREE_FEK_SIZE); 505 if (res != TEE_SUCCESS) 506 goto exit; 507 508 res = crypto_ops.authenc.update_aad(ctx, alg, mode, 509 (void *)&ht->head.counter, 510 sizeof(ht->head.counter)); 511 if (res != TEE_SUCCESS) 512 goto exit; 513 } 514 515 res = crypto_ops.authenc.update_aad(ctx, alg, mode, ht->head.enc_fek, 516 TEE_FS_HTREE_FEK_SIZE); 517 if (res != TEE_SUCCESS) 518 goto exit; 519 520 res = crypto_ops.authenc.update_aad(ctx, alg, mode, iv, 521 TEE_FS_HTREE_IV_SIZE); 522 523 exit: 524 if (res == TEE_SUCCESS) 525 *ctx_ret = ctx; 526 else 527 free(ctx); 528 529 return res; 530 } 531 532 static TEE_Result authenc_decrypt_final(void *ctx, const uint8_t *tag, 533 const void *crypt, size_t len, 534 void *plain) 535 { 536 TEE_Result res; 537 size_t out_size = len; 538 539 res = crypto_ops.authenc.dec_final(ctx, TEE_FS_HTREE_AUTH_ENC_ALG, 540 crypt, len, plain, &out_size, 541 tag, TEE_FS_HTREE_TAG_SIZE); 542 crypto_ops.authenc.final(ctx, TEE_FS_HTREE_AUTH_ENC_ALG); 543 free(ctx); 544 545 if (res == TEE_SUCCESS && out_size != len) 546 return TEE_ERROR_GENERIC; 547 if (res == TEE_ERROR_MAC_INVALID) 548 return TEE_ERROR_CORRUPT_OBJECT; 549 550 return res; 551 } 552 553 static TEE_Result authenc_encrypt_final(void *ctx, uint8_t *tag, 554 const void *plain, size_t len, 555 void *crypt) 556 { 557 TEE_Result res; 558 size_t out_size = len; 559 size_t out_tag_size = TEE_FS_HTREE_TAG_SIZE; 560 561 res = crypto_ops.authenc.enc_final(ctx, TEE_FS_HTREE_AUTH_ENC_ALG, 562 plain, len, crypt, &out_size, 563 tag, &out_tag_size); 564 crypto_ops.authenc.final(ctx, TEE_FS_HTREE_AUTH_ENC_ALG); 565 free(ctx); 566 567 if (res == TEE_SUCCESS && 568 (out_size != len || out_tag_size != TEE_FS_HTREE_TAG_SIZE)) 569 return TEE_ERROR_GENERIC; 570 571 return res; 572 } 573 574 static TEE_Result verify_root(struct tee_fs_htree *ht) 575 { 576 TEE_Result res; 577 void *ctx; 578 579 res = tee_fs_fek_crypt(TEE_MODE_DECRYPT, ht->head.enc_fek, 580 sizeof(ht->fek), ht->fek); 581 if (res != TEE_SUCCESS) 582 return res; 583 584 res = authenc_init(&ctx, TEE_MODE_DECRYPT, ht, NULL, sizeof(ht->imeta)); 585 if (res != TEE_SUCCESS) 586 return res; 587 588 return authenc_decrypt_final(ctx, ht->head.tag, ht->head.imeta, 589 sizeof(ht->imeta), &ht->imeta); 590 } 591 592 static TEE_Result verify_node(struct traverse_arg *targ, 593 struct htree_node *node) 594 { 595 void *ctx = targ->arg; 596 TEE_Result res; 597 uint8_t digest[TEE_FS_HTREE_HASH_SIZE]; 598 599 res = calc_node_hash(node, ctx, digest); 600 if (res == TEE_SUCCESS && 601 buf_compare_ct(digest, node->node.hash, sizeof(digest))) 602 return TEE_ERROR_CORRUPT_OBJECT; 603 604 return res; 605 } 606 607 static TEE_Result verify_tree(struct tee_fs_htree *ht) 608 { 609 TEE_Result res; 610 size_t size; 611 void *ctx; 612 613 if (!crypto_ops.hash.get_ctx_size || !crypto_ops.hash.init || 614 !crypto_ops.hash.update || !crypto_ops.hash.final) 615 return TEE_ERROR_NOT_SUPPORTED; 616 617 res = crypto_ops.hash.get_ctx_size(TEE_FS_HTREE_HASH_ALG, &size); 618 if (res != TEE_SUCCESS) 619 return res; 620 621 ctx = malloc(size); 622 if (!ctx) 623 return TEE_ERROR_OUT_OF_MEMORY; 624 625 res = htree_traverse_post_order(ht, verify_node, ctx); 626 free(ctx); 627 628 return res; 629 } 630 631 static TEE_Result init_root_node(struct tee_fs_htree *ht) 632 { 633 TEE_Result res; 634 size_t size; 635 void *ctx; 636 637 res = crypto_ops.hash.get_ctx_size(TEE_FS_HTREE_HASH_ALG, &size); 638 if (res != TEE_SUCCESS) 639 return res; 640 ctx = malloc(size); 641 if (!ctx) 642 return TEE_ERROR_OUT_OF_MEMORY; 643 644 ht->root.id = 1; 645 646 res = calc_node_hash(&ht->root, ctx, ht->root.node.hash); 647 free(ctx); 648 649 return res; 650 } 651 652 TEE_Result tee_fs_htree_open(bool create, uint8_t *hash, 653 const struct tee_fs_htree_storage *stor, 654 void *stor_aux, struct tee_fs_htree **ht_ret) 655 { 656 TEE_Result res; 657 struct tee_fs_htree *ht = calloc(1, sizeof(*ht)); 658 659 if (!ht) 660 return TEE_ERROR_OUT_OF_MEMORY; 661 662 ht->stor = stor; 663 ht->stor_aux = stor_aux; 664 665 if (create) { 666 const struct tee_fs_htree_image dummy_head = { .counter = 0 }; 667 668 res = crypto_ops.prng.read(ht->fek, sizeof(ht->fek)); 669 if (res != TEE_SUCCESS) 670 goto out; 671 672 res = tee_fs_fek_crypt(TEE_MODE_ENCRYPT, ht->fek, 673 sizeof(ht->fek), ht->head.enc_fek); 674 if (res != TEE_SUCCESS) 675 goto out; 676 677 res = init_root_node(ht); 678 if (res != TEE_SUCCESS) 679 goto out; 680 681 ht->dirty = true; 682 res = tee_fs_htree_sync_to_storage(&ht, hash); 683 if (res != TEE_SUCCESS) 684 goto out; 685 res = rpc_write_head(ht, 0, &dummy_head); 686 } else { 687 res = init_head_from_data(ht, hash); 688 if (res != TEE_SUCCESS) 689 goto out; 690 691 res = verify_root(ht); 692 if (res != TEE_SUCCESS) 693 goto out; 694 695 res = init_tree_from_data(ht); 696 if (res != TEE_SUCCESS) 697 goto out; 698 699 res = verify_tree(ht); 700 } 701 out: 702 if (res == TEE_SUCCESS) 703 *ht_ret = ht; 704 else 705 tee_fs_htree_close(&ht); 706 return res; 707 } 708 709 struct tee_fs_htree_meta *tee_fs_htree_get_meta(struct tee_fs_htree *ht) 710 { 711 return &ht->imeta.meta; 712 } 713 714 static TEE_Result free_node(struct traverse_arg *targ __unused, 715 struct htree_node *node) 716 { 717 if (node->parent) 718 free(node); 719 return TEE_SUCCESS; 720 } 721 722 void tee_fs_htree_close(struct tee_fs_htree **ht) 723 { 724 if (!*ht) 725 return; 726 htree_traverse_post_order(*ht, free_node, NULL); 727 free(*ht); 728 *ht = NULL; 729 } 730 731 static TEE_Result htree_sync_node_to_storage(struct traverse_arg *targ, 732 struct htree_node *node) 733 { 734 TEE_Result res; 735 uint8_t vers; 736 737 /* 738 * The node can be dirty while the block isn't updated due to 739 * updated children, but if block is updated the node has to be 740 * dirty. 741 */ 742 assert(node->dirty >= node->block_updated); 743 744 if (!node->dirty) 745 return TEE_SUCCESS; 746 747 if (node->parent) { 748 uint32_t f = HTREE_NODE_COMMITTED_CHILD(node->id & 1); 749 750 node->parent->dirty = true; 751 node->parent->node.flags ^= f; 752 vers = !!(node->parent->node.flags & f); 753 } else { 754 /* 755 * Counter isn't updated yet, it's increased just before 756 * writing the header. 757 */ 758 vers = !(targ->ht->head.counter & 1); 759 } 760 761 res = calc_node_hash(node, targ->arg, node->node.hash); 762 if (res != TEE_SUCCESS) 763 return res; 764 765 node->dirty = false; 766 node->block_updated = false; 767 768 return rpc_write_node(targ->ht, node->id, vers, &node->node); 769 } 770 771 static TEE_Result update_root(struct tee_fs_htree *ht) 772 { 773 TEE_Result res; 774 void *ctx; 775 776 ht->head.counter++; 777 778 res = authenc_init(&ctx, TEE_MODE_ENCRYPT, ht, NULL, sizeof(ht->imeta)); 779 if (res != TEE_SUCCESS) 780 return res; 781 782 return authenc_encrypt_final(ctx, ht->head.tag, &ht->imeta, 783 sizeof(ht->imeta), &ht->head.imeta); 784 } 785 786 TEE_Result tee_fs_htree_sync_to_storage(struct tee_fs_htree **ht_arg, 787 uint8_t *hash) 788 { 789 TEE_Result res; 790 struct tee_fs_htree *ht = *ht_arg; 791 size_t size; 792 void *ctx; 793 794 if (!ht) 795 return TEE_ERROR_CORRUPT_OBJECT; 796 797 if (!ht->dirty) 798 return TEE_SUCCESS; 799 800 res = crypto_ops.hash.get_ctx_size(TEE_FS_HTREE_HASH_ALG, &size); 801 if (res != TEE_SUCCESS) 802 return res; 803 ctx = malloc(size); 804 if (!ctx) 805 return TEE_ERROR_OUT_OF_MEMORY; 806 807 res = htree_traverse_post_order(ht, htree_sync_node_to_storage, ctx); 808 if (res != TEE_SUCCESS) 809 goto out; 810 811 /* All the nodes are written to storage now. Time to update root. */ 812 res = update_root(ht); 813 if (res != TEE_SUCCESS) 814 goto out; 815 816 res = rpc_write_head(ht, ht->head.counter & 1, &ht->head); 817 if (res != TEE_SUCCESS) 818 goto out; 819 820 ht->dirty = false; 821 if (hash) 822 memcpy(hash, ht->root.node.hash, sizeof(ht->root.node.hash)); 823 out: 824 free(ctx); 825 if (res != TEE_SUCCESS) 826 tee_fs_htree_close(ht_arg); 827 return res; 828 } 829 830 static TEE_Result get_block_node(struct tee_fs_htree *ht, bool create, 831 size_t block_num, struct htree_node **node) 832 { 833 TEE_Result res; 834 struct htree_node *nd; 835 836 res = get_node(ht, create, BLOCK_NUM_TO_NODE_ID(block_num), &nd); 837 if (res == TEE_SUCCESS) 838 *node = nd; 839 840 return res; 841 } 842 843 TEE_Result tee_fs_htree_write_block(struct tee_fs_htree **ht_arg, 844 size_t block_num, const void *block) 845 { 846 struct tee_fs_htree *ht = *ht_arg; 847 TEE_Result res; 848 struct tee_fs_rpc_operation op; 849 struct htree_node *node = NULL; 850 uint8_t block_vers; 851 void *ctx; 852 void *enc_block; 853 854 if (!ht) 855 return TEE_ERROR_CORRUPT_OBJECT; 856 857 res = get_block_node(ht, true, block_num, &node); 858 if (res != TEE_SUCCESS) 859 goto out; 860 861 if (!node->block_updated) 862 node->node.flags ^= HTREE_NODE_COMMITTED_BLOCK; 863 864 block_vers = !!(node->node.flags & HTREE_NODE_COMMITTED_BLOCK); 865 res = ht->stor->rpc_write_init(ht->stor_aux, &op, 866 TEE_FS_HTREE_TYPE_BLOCK, block_num, 867 block_vers, &enc_block); 868 if (res != TEE_SUCCESS) 869 goto out; 870 871 res = authenc_init(&ctx, TEE_MODE_ENCRYPT, ht, &node->node, 872 ht->stor->block_size); 873 if (res != TEE_SUCCESS) 874 goto out; 875 res = authenc_encrypt_final(ctx, node->node.tag, block, 876 ht->stor->block_size, enc_block); 877 if (res != TEE_SUCCESS) 878 goto out; 879 880 res = ht->stor->rpc_write_final(&op); 881 if (res != TEE_SUCCESS) 882 goto out; 883 884 node->block_updated = true; 885 node->dirty = true; 886 ht->dirty = true; 887 out: 888 if (res != TEE_SUCCESS) 889 tee_fs_htree_close(ht_arg); 890 return res; 891 } 892 893 TEE_Result tee_fs_htree_read_block(struct tee_fs_htree **ht_arg, 894 size_t block_num, void *block) 895 { 896 struct tee_fs_htree *ht = *ht_arg; 897 TEE_Result res; 898 struct tee_fs_rpc_operation op; 899 struct htree_node *node; 900 uint8_t block_vers; 901 size_t len; 902 void *ctx; 903 void *enc_block; 904 905 if (!ht) 906 return TEE_ERROR_CORRUPT_OBJECT; 907 908 res = get_block_node(ht, false, block_num, &node); 909 if (res != TEE_SUCCESS) 910 goto out; 911 912 block_vers = !!(node->node.flags & HTREE_NODE_COMMITTED_BLOCK); 913 res = ht->stor->rpc_read_init(ht->stor_aux, &op, 914 TEE_FS_HTREE_TYPE_BLOCK, block_num, 915 block_vers, &enc_block); 916 if (res != TEE_SUCCESS) 917 goto out; 918 919 res = ht->stor->rpc_read_final(&op, &len); 920 if (res != TEE_SUCCESS) 921 goto out; 922 if (len != ht->stor->block_size) { 923 res = TEE_ERROR_CORRUPT_OBJECT; 924 goto out; 925 } 926 927 res = authenc_init(&ctx, TEE_MODE_DECRYPT, ht, &node->node, 928 ht->stor->block_size); 929 if (res != TEE_SUCCESS) 930 goto out; 931 932 res = authenc_decrypt_final(ctx, node->node.tag, enc_block, 933 ht->stor->block_size, block); 934 out: 935 if (res != TEE_SUCCESS) 936 tee_fs_htree_close(ht_arg); 937 return res; 938 } 939 940 TEE_Result tee_fs_htree_truncate(struct tee_fs_htree **ht_arg, size_t block_num) 941 { 942 struct tee_fs_htree *ht = *ht_arg; 943 size_t node_id = BLOCK_NUM_TO_NODE_ID(block_num); 944 struct htree_node *node; 945 946 if (!ht) 947 return TEE_ERROR_CORRUPT_OBJECT; 948 949 while (node_id < ht->imeta.max_node_id) { 950 node = find_closest_node(ht, ht->imeta.max_node_id); 951 assert(node && node->id == ht->imeta.max_node_id); 952 assert(!node->child[0] && !node->child[1]); 953 assert(node->parent); 954 assert(node->parent->child[node->id & 1] == node); 955 node->parent->child[node->id & 1] = NULL; 956 free(node); 957 ht->imeta.max_node_id--; 958 ht->dirty = true; 959 } 960 961 return TEE_SUCCESS; 962 } 963