| /* Copyright (c) 2010 The Chromium OS Authors. All rights reserved. |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef VBOOT_REFERENCE_CGPTLIB_H_ |
| #define VBOOT_REFERENCE_CGPTLIB_H_ |
| |
| #include "sysincludes.h" |
| |
| enum { |
| GPT_SUCCESS = 0, |
| GPT_ERROR_NO_VALID_KERNEL, |
| GPT_ERROR_INVALID_HEADERS, |
| GPT_ERROR_INVALID_ENTRIES, |
| GPT_ERROR_INVALID_SECTOR_SIZE, |
| GPT_ERROR_INVALID_SECTOR_NUMBER, |
| GPT_ERROR_INVALID_UPDATE_TYPE, |
| }; |
| |
| /* Bit masks for GptData.modified field. */ |
| #define GPT_MODIFIED_HEADER1 0x01 |
| #define GPT_MODIFIED_HEADER2 0x02 |
| #define GPT_MODIFIED_ENTRIES1 0x04 |
| #define GPT_MODIFIED_ENTRIES2 0x08 |
| |
| #define TOTAL_ENTRIES_SIZE 16384 /* Size of GptData.primary_entries |
| * and secondary_entries: 128 |
| * bytes/entry * 128 entries. */ |
| |
| /* The 'update_type' of GptUpdateKernelEntry() |
| * We expose TRY and BAD only because those are what verified boot needs. |
| * For more precise control on GPT attribute bits, please refer to |
| * gpt_internal.h */ |
| enum { |
| GPT_UPDATE_ENTRY_TRY = 1, |
| /* System will be trying to boot the currently selected kernel partition. |
| * Update its try count if necessary. */ |
| GPT_UPDATE_ENTRY_BAD = 2, |
| /* The currently selected kernel partition failed validation. Mark entry as |
| * invalid. */ |
| }; |
| |
| typedef struct { |
| /* Fill in the following fields before calling GptInit() */ |
| uint8_t *primary_header; /* GPT primary header, from sector 1 of disk |
| * (size: 512 bytes) */ |
| uint8_t *secondary_header; /* GPT secondary header, from last sector of |
| * disk (size: 512 bytes) */ |
| uint8_t *primary_entries; /* primary GPT table, follows primary header |
| * (size: 16 KB) */ |
| uint8_t *secondary_entries; /* secondary GPT table, precedes secondary |
| * header (size: 16 KB) */ |
| uint32_t sector_bytes; /* Size of a LBA sector, in bytes */ |
| uint64_t drive_sectors; /* Size of drive in LBA sectors, in sectors */ |
| |
| /* Outputs */ |
| uint8_t modified; /* Which inputs have been modified? |
| * 0x01 = header1 |
| * 0x02 = header2 |
| * 0x04 = table1 |
| * 0x08 = table2 */ |
| int current_kernel; /* the current chromeos kernel index in partition table. |
| * -1 means not found on drive. Note that GPT partition |
| * numbers are traditionally 1-based, but we're using |
| * a zero-based index here. |
| */ |
| |
| /* Internal variables */ |
| uint32_t valid_headers, valid_entries; |
| int current_priority; |
| } GptData; |
| |
| int GptInit(GptData* gpt); |
| /* Initializes the GPT data structure's internal state. The following fields |
| * must be filled before calling this function: |
| * |
| * primary_header |
| * secondary_header |
| * primary_entries |
| * secondary_entries |
| * sector_bytes |
| * drive_sectors |
| * |
| * On return the modified field may be set, if the GPT data has been modified |
| * and should be written to disk. |
| * |
| * Returns GPT_SUCCESS if successful, non-zero if error: |
| * GPT_ERROR_INVALID_HEADERS, both partition table headers are invalid, enters |
| * recovery mode, |
| * GPT_ERROR_INVALID_ENTRIES, both partition table entries are invalid, enters |
| * recovery mode, |
| * GPT_ERROR_INVALID_SECTOR_SIZE, size of a sector is not supported, |
| * GPT_ERROR_INVALID_SECTOR_NUMBER, number of sectors in drive is invalid (too |
| * small) */ |
| |
| int GptNextKernelEntry(GptData* gpt, uint64_t* start_sector, uint64_t* size); |
| /* Provides the location of the next kernel partition, in order of decreasing |
| * priority. On return the start_sector parameter contains the LBA sector |
| * for the start of the kernel partition, and the size parameter contains the |
| * size of the kernel partition in LBA sectors. gpt.current_kernel contains |
| * the partition index of the current chromeos kernel partition. |
| * |
| * Returns GPT_SUCCESS if successful, else |
| * GPT_ERROR_NO_VALID_KERNEL, no avaliable kernel, enters recovery mode */ |
| |
| int GptUpdateKernelEntry(GptData* gpt, uint32_t update_type); |
| /* Updates the kernel entry with the specified index, using the specified type |
| * of update (GPT_UPDATE_ENTRY_*). |
| * |
| * On return the modified field may be set, if the GPT data has been modified |
| * and should be written to disk. |
| * |
| * Returns GPT_SUCCESS if successful, else |
| * GPT_ERROR_INVALID_UPDATE_TYPE, invalid 'update_type' is given. |
| */ |
| |
| #endif /* VBOOT_REFERENCE_CGPTLIB_H_ */ |