cgptlib stub for verified boot development.

src/platform/vboot_reference/cgptlib/cgpt.h

+/* 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_CGPT_H_
+#define VBOOT_REFERENCE_CGPT_H_
+
+#include <stdint.h>
+
+enum {
+        GPT_ERROR_INVALID_HEADERS = 1,
+        GPT_ERROR_INVALID_ENTRIES,
+        GPT_ERROR_INVALID_SECTOR_SIZE,
+        GPT_ERROR_INVALID_SECTOR_NUMBER,
+};
+
+#define GPT_MODIFIED_HEADER1 0x01
+#define GPT_MODIFIED_HEADER2 0x02
+#define GPT_MODIFIED_ENTRIES1 0x04
+#define GPT_MODIFIED_ENTRIES2 0x08
+
+#define GPT_UPDATE_ENTRY_TRY 1
+  /* System will be trying to boot the currently selected kernel partition.
+   * Update its try count if necessary. */
+#define GPT_UPDATE_ENTRY_BAD 2
+  /* The currently selected kernel partition failed validation.  Mark entry as
+   * invalid. */
+
+struct GPTData {
+        /* Fill in the following fields before calling GPTInit() */
+        uint8_t *header1;       /* GPT primary header, from sector 1 of disk 
+                                 *   (size: 512 bytes) */
+        uint8_t *header2;       /* GPT secondary header, from last sector of
+                                 *   disk (size: 512 bytes) */
+        uint8_t *entries1;      /* primary GPT table, follows primary header 
+                                 *   (size: 16 KB) */
+        uint8_t *entries2;      /* 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  */
+
+        /* Internal state */
+        uint8_t current_kernel; // the current kernel index
+};
+typedef struct GPTData GPTData_t;
+
+int GPTInit(GPTData_t *gpt);
+/* Initializes the GPT data structure's internal state.  The header1, header2,
+ * table1, table2, and drive_size fields should be filled in first.
+ *
+ * On return the modified field may be set, if the GPT data has been modified
+ * and should be written to disk.
+ *
+ * Returns 0 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_t *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.
+ *
+ * Returns 0 if successful, 1 if error or no more sectors.  */
+
+int GPTUpdateKernelEntry(GPTData_t *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 0 if successful, 1 if error. */
+
+#endif  // VBOOT_REFERENCE_CGPT_H_