src/neboot-partition-map-parse.c


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/* -------------------------------------------

  Copyright (C) 2024, Amlal El Mahrouss, licensed under Apache 2.0.

------------------------------------------- */

#include <lib/partition-map.h>

bool cb_parse_partition_block_data_at(voidptr_t blob, size_t blob_sz, size_t index, size_t* end_lba,
                                      size_t* start_lba, size_t* sector_sz) {
  if (!start_lba || !end_lba || !blob || !blob_sz || !sector_sz ||
      (sizeof(part_block_t) * index) > blob_sz)
    return false;

  part_block_t* block = (part_block_t*) (blob + (sizeof(part_block_t) * index));

  if (block->version != EPM_REVISION || block->num_blocks < 1 || block->num_blocks > EPM_MAX_BLKS ||
      strcmp(block->magic, EPM_MAGIC) > 0 || block->lba_end == 0 || block->lba_start == 0) {
    return false;
  }

  *end_lba   = block->lba_end;
  *start_lba = block->lba_start;
  *sector_sz = block->sector_sz;

  return true;
}

part_block_t* cb_parse_partition_block_at(voidptr_t blob, size_t blob_sz, size_t index) {
  if (!blob || !blob_sz || (sizeof(part_block_t) * index) > blob_sz) return nil;

  part_block_t* block = (part_block_t*) (blob + (sizeof(part_block_t) * index));

  cb_put_string(block->magic);

  if (block->version != EPM_REVISION || block->num_blocks < 1 || block->num_blocks > EPM_MAX_BLKS ||
      strcmp(block->magic, EPM_MAGIC) > 0 || block->lba_end == 0 || block->lba_start == 0) {
    return nil;
  }

  return block;
}