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/* 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_ */
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