avb_hashtree_descriptor.c 1.9 KB

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  1. // SPDX-License-Identifier: MIT
  2. /*
  3. * Copyright (C) 2016 The Android Open Source Project
  4. */
  5. #include "avb_hashtree_descriptor.h"
  6. #include "avb_util.h"
  7. bool avb_hashtree_descriptor_validate_and_byteswap(
  8. const AvbHashtreeDescriptor* src, AvbHashtreeDescriptor* dest) {
  9. uint64_t expected_size;
  10. avb_memcpy(dest, src, sizeof(AvbHashtreeDescriptor));
  11. if (!avb_descriptor_validate_and_byteswap((const AvbDescriptor*)src,
  12. (AvbDescriptor*)dest))
  13. return false;
  14. if (dest->parent_descriptor.tag != AVB_DESCRIPTOR_TAG_HASHTREE) {
  15. avb_error("Invalid tag for hashtree descriptor.\n");
  16. return false;
  17. }
  18. dest->dm_verity_version = avb_be32toh(dest->dm_verity_version);
  19. dest->image_size = avb_be64toh(dest->image_size);
  20. dest->tree_offset = avb_be64toh(dest->tree_offset);
  21. dest->tree_size = avb_be64toh(dest->tree_size);
  22. dest->data_block_size = avb_be32toh(dest->data_block_size);
  23. dest->hash_block_size = avb_be32toh(dest->hash_block_size);
  24. dest->fec_num_roots = avb_be32toh(dest->fec_num_roots);
  25. dest->fec_offset = avb_be64toh(dest->fec_offset);
  26. dest->fec_size = avb_be64toh(dest->fec_size);
  27. dest->partition_name_len = avb_be32toh(dest->partition_name_len);
  28. dest->salt_len = avb_be32toh(dest->salt_len);
  29. dest->root_digest_len = avb_be32toh(dest->root_digest_len);
  30. dest->flags = avb_be32toh(dest->flags);
  31. /* Check that partition_name, salt, and root_digest are fully contained. */
  32. expected_size = sizeof(AvbHashtreeDescriptor) - sizeof(AvbDescriptor);
  33. if (!avb_safe_add_to(&expected_size, dest->partition_name_len) ||
  34. !avb_safe_add_to(&expected_size, dest->salt_len) ||
  35. !avb_safe_add_to(&expected_size, dest->root_digest_len)) {
  36. avb_error("Overflow while adding up sizes.\n");
  37. return false;
  38. }
  39. if (expected_size > dest->parent_descriptor.num_bytes_following) {
  40. avb_error("Descriptor payload size overflow.\n");
  41. return false;
  42. }
  43. return true;
  44. }