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/* Copyright (c) 2014 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.
 *
 * Data structure definitions for verified boot, for on-disk / in-eeprom
 * data.
 */

#ifndef VBOOT_REFERENCE_VBOOT_2STRUCT_H_
#define VBOOT_REFERENCE_VBOOT_2STRUCT_H_
#include <stdint.h>

/****************************************************************************/
/* GUID structure.  Defined in appendix A of EFI standard. */

#define UUID_NODE_LEN 6
#define GUID_SIZE 16

struct vb2_guid {
	union {
		struct {
			uint32_t time_low;
			uint16_t time_mid;
			uint16_t time_high_and_version;
			uint8_t clock_seq_high_and_reserved;
			uint8_t clock_seq_low;
			uint8_t node[UUID_NODE_LEN];
		} uuid;
		uint8_t raw[GUID_SIZE];
	};
} __attribute__((packed));

#define EXPECTED_GUID_SIZE GUID_SIZE

/* Key GUIDs to use for VB2_SIG_NONE and hash algorithms */

#define VB2_GUID_NONE_SHA1 \
	{{{0xcfb5687a,0x6092,0x11e4,0x96,0xe1,{0x8f,0x3b,0x1a,0x60,0xa2,0x1d}}}}

#define VB2_GUID_NONE_SHA256 \
	{{{0x0e4114e0,0x6093,0x11e4,0x9d,0xcb,{0x8f,0x8a,0xf4,0xca,0x2e,0x32}}}}

#define VB2_GUID_NONE_SHA512 \
	{{{0x1c695960,0x6093,0x11e4,0x82,0x63,{0xdb,0xee,0xe9,0x3c,0xcd,0x7e}}}}

/****************************************************************************/
/*
 * Vboot1-compatible data structures
 *
 *
 * Note: Many of the structs have pairs of 32-bit fields and reserved fields.
 * This is to be backwards-compatible with older verified boot data which used
 * 64-bit fields (when we thought that hey, UEFI is 64-bit so all our fields
 * should be too).
 */

/* Packed public key data */
struct vb2_packed_key {
	/* Offset of key data from start of this struct */
	uint32_t key_offset;
	uint32_t reserved0;

	/* Size of key data in bytes (NOT strength of key in bits) */
	uint32_t key_size;
	uint32_t reserved1;

	/* Signature algorithm used by the key (enum vb2_crypto_algorithm) */
	uint32_t algorithm;
	uint32_t reserved2;

	/* Key version */
	uint32_t key_version;
	uint32_t reserved3;

	/* TODO: when redoing this struct, add a text description of the key */
} __attribute__((packed));

#define EXPECTED_VB2_PACKED_KEY_SIZE 32

/* Signature data (a secure hash, possibly signed) */
struct vb2_signature {
	/* Offset of signature data from start of this struct */
	uint32_t sig_offset;
	uint32_t reserved0;

	/* Size of signature data in bytes */
	uint32_t sig_size;
	uint32_t reserved1;

	/* Size of the data block which was signed in bytes */
	uint32_t data_size;
	uint32_t reserved2;
} __attribute__((packed));

#define EXPECTED_VB2_SIGNATURE_SIZE 24

#define KEY_BLOCK_MAGIC "CHROMEOS"
#define KEY_BLOCK_MAGIC_SIZE 8

#define KEY_BLOCK_HEADER_VERSION_MAJOR 2
#define KEY_BLOCK_HEADER_VERSION_MINOR 1

/*
 * The following flags set where the key is valid.  Not used by firmware
 * verification; only kernel verification.
 */
#define VB2_KEY_BLOCK_FLAG_DEVELOPER_0  0x01 /* Developer switch off */
#define VB2_KEY_BLOCK_FLAG_DEVELOPER_1  0x02 /* Developer switch on */
#define VB2_KEY_BLOCK_FLAG_RECOVERY_0   0x04 /* Not recovery mode */
#define VB2_KEY_BLOCK_FLAG_RECOVERY_1   0x08 /* Recovery mode */

/*
 * Key block, containing the public key used to sign some other chunk of data.
 *
 * This should be followed by:
 *   1) The data_key key data, pointed to by data_key.key_offset.
 *   2) The checksum data for (vb2_keyblock + data_key data), pointed to
 *      by keyblock_checksum.sig_offset.
 *   3) The signature data for (vb2_keyblock + data_key data), pointed to
 *      by keyblock_signature.sig_offset.
 */
struct vb2_keyblock {
	/* Magic number */
	uint8_t magic[KEY_BLOCK_MAGIC_SIZE];

	/* Version of this header format */
	uint32_t header_version_major;

	/* Version of this header format */
	uint32_t header_version_minor;

	/*
	 * Length of this entire key block, including keys, signatures, and
	 * padding, in bytes
	 */
	uint32_t keyblock_size;
	uint32_t reserved0;

	/*
	 * Signature for this key block (header + data pointed to by data_key)
	 * For use with signed data keys
	 */
	struct vb2_signature keyblock_signature;

	/*
	 * SHA-512 checksum for this key block (header + data pointed to by
	 * data_key) For use with unsigned data keys.
	 *
	 * Note that the vb2 lib currently only supports signed blocks.
	 */
	struct vb2_signature keyblock_checksum_unused;

	/* Flags for key (VB2_KEY_BLOCK_FLAG_*) */
	uint32_t keyblock_flags;
	uint32_t reserved1;

	/* Key to verify the chunk of data */
	struct vb2_packed_key data_key;
} __attribute__((packed));

#define EXPECTED_VB2_KEYBLOCK_SIZE 112


/* Firmware preamble header */
#define FIRMWARE_PREAMBLE_HEADER_VERSION_MAJOR 2
#define FIRMWARE_PREAMBLE_HEADER_VERSION_MINOR 1

/* Flags for VbFirmwarePreambleHeader.flags */
/* Reserved; do not use */
#define VB2_FIRMWARE_PREAMBLE_RESERVED0 0x00000001

/* Premable block for rewritable firmware, version 2.1.
 *
 * The firmware preamble header should be followed by:
 *   1) The kernel_subkey key data, pointed to by kernel_subkey.key_offset.
 *   2) The signature data for the firmware body, pointed to by
 *      body_signature.sig_offset.
 *   3) The signature data for (header + kernel_subkey data + body signature
 *      data), pointed to by preamble_signature.sig_offset.
 */
struct vb2_fw_preamble {
	/*
	 * Size of this preamble, including keys, signatures, and padding, in
	 * bytes
	 */
	uint32_t preamble_size;
	uint32_t reserved0;

	/*
	 * Signature for this preamble (header + kernel subkey + body
	 * signature)
	 */
	struct vb2_signature preamble_signature;

	/* Version of this header format */
	uint32_t header_version_major;
	uint32_t header_version_minor;

	/* Firmware version */
	uint32_t firmware_version;
	uint32_t reserved1;

	/* Key to verify kernel key block */
	struct vb2_packed_key kernel_subkey;

	/* Signature for the firmware body */
	struct vb2_signature body_signature;

	/*
	 * Fields added in header version 2.1.  You must verify the header
	 * version before reading these fields!
	 */

	/*
	 * Flags; see VB2_FIRMWARE_PREAMBLE_*.  Readers should return 0 for
	 * header version < 2.1.
	 */
	uint32_t flags;
} __attribute__((packed));

#define EXPECTED_VB2_FW_PREAMBLE_SIZE 108

/****************************************************************************/
/*
 * Vboot2 data structures
 *
 *
 * Offsets should be padded to 32-bit boundaries, since some architectures
 * have trouble with accessing unaligned integers.
 */

/*
 * Magic numbers used by vb2_struct_common.magic.
 *
 * All valid numbers should be listed here to avoid accidental overlap.
 * Numbers start at a large value, so that previous parsers (which stored
 * things like lengths and offsets at that field) will detect and reject new
 * structs as invalid.
 */
enum vb2_struct_common_magic {
	/* "Vb2B" = vb2_keyblock2.c.magic */
	VB2_MAGIC_KEYBLOCK2        = 0x42326256,

	/* "Vb2F" = vb2_fw_preamble.c.magic */
	VB2_MAGIC_FW_PREAMBLE2     = 0x46326256,

	/* "Vb2K" = vb2_kernel_preamble.c.magic */
	VB2_MAGIC_KERNEL_PREAMBLE2 = 0x4b326256,

	/* "Vb2P" = vb2_packed_key2.c.magic */
	VB2_MAGIC_PACKED_KEY2      = 0x50326256,

	/* "Vb2S" = vb2_signature.c.magic */
	VB2_MAGIC_SIGNATURE2       = 0x53326256,
};


/*
 * Generic struct header for all vboot2 structs.  This makes it easy to
 * automatically parse and identify vboot structs (e.g., in futility).  This
 * must be the first member of the parent vboot2 struct.
 */
struct vb2_struct_common {
	/* Magic number; see vb2_struct_common_magic for expected values */
	uint32_t magic;

	/*
	 * Parent struct version; see each struct for the expected value.
	 *
	 * How to handle struct version mismatches, if the parser is version
	 * A.b and the data is version C.d:
	 *     1) If A.b == C.d, we're good.
	 *     2) If A != C, the data cannot be parsed at all.
	 *     3) If b < d, C.d is a newer version of data which is backwards-
	 *        compatible to old parsers.  We're good.
	 *     4) If b > d, C.d is an older version of data.  The parser should
	 *        use default values for fields added after version d.  We're
	 *        good.
	 *
	 * Struct versions start at 3.0, since the highest version of the old
	 * structures was 2.1.  This way, there is no possibility of collision
	 * for old code which depends on the version number.
	 */
	uint16_t struct_version_major;
	uint16_t struct_version_minor;

	/*
	 * Size of the parent structure and all its data, including the
	 * description and any necessary padding.  That is, all data must lie
	 * in a contiguous region of <total_size> bytes starting at the first
	 * byte of this header.
	 */
	uint32_t total_size;

	/*
	 * Size of the fixed portion of the parent structure.  If a description
	 * is present, it must start at this offset.
	 */
	uint32_t fixed_size;

	/*
	 * The object may contain an ASCII description following the fixed
	 * portion of the structure.  If it is present, it must be
	 * null-terminated, and padded with 0 (null) bytes to a multiple of 32
	 * bits.
	 *
	 * Size of ASCII description in bytes, counting null terminator and
	 * padding (if any).  Set 0 if no description is present.  If non-zero,
	 * there must be a null terminator (0) at offset (fixed_size +
	 * desc_size - 1).
	 */
	uint32_t desc_size;
} __attribute__((packed));

#define EXPECTED_VB2_STRUCT_COMMON_SIZE 20

/* Algorithm types for signatures */
enum vb2_signature_algorithm {
	/* Invalid or unsupported signature type */
	VB2_SIG_INVALID = 0,

	/*
	 * No signature algorithm.  The digest is unsigned.  See
	 * VB2_GUID_NONE_* above for key GUIDs to use with this algorithm.
	 */
	VB2_SIG_NONE = 1,

	/* RSA algorithms of the given length in bits (1024-8192) */
	VB2_SIG_RSA1024 = 2,  /* Warning!  This is likely to be deprecated! */
	VB2_SIG_RSA2048 = 3,
	VB2_SIG_RSA4096 = 4,
	VB2_SIG_RSA8192 = 5,
};

/* Algorithm types for hash digests */
enum vb2_hash_algorithm {
	/* Invalid or unsupported digest type */
	VB2_HASH_INVALID = 0,

	/* SHA-1.  Warning: This is likely to be deprecated soon! */
	VB2_HASH_SHA1 = 1,

	/* SHA-256 and SHA-512 */
	VB2_HASH_SHA256 = 2,
	VB2_HASH_SHA512 = 3,
};

/* Current version of vb2_packed_key2 struct */
#define VB2_PACKED_KEY2_VERSION_MAJOR 3
#define VB2_PACKED_KEY2_VERSION_MINOR 0

/*
 * Packed public key data, version 2
 *
 * The key data must be arranged like this:
 *     1) vb2_packed_key2 header struct h
 *     2) Key description (pointed to by h.c.fixed_size)
 *     3) Key data key (pointed to by h.key_offset)
 */
struct vb2_packed_key2 {
	/* Common header fields */
	struct vb2_struct_common c;

	/* Offset of key data from start of this struct */
	uint32_t key_offset;

	/* Size of key data in bytes (NOT strength of key in bits) */
	uint32_t key_size;

	/* Signature algorithm used by the key (enum vb2_signature_algorithm) */
	uint16_t sig_alg;

	/*
	 * Hash digest algorithm used with the key (enum vb2_hash_algorithm).
	 * This is explicitly specified as part of the key to prevent use of a
	 * strong key with a weak hash.
	 */
	uint16_t hash_alg;

	/* Key version */
	uint32_t key_version;

	/* Key GUID */
	struct vb2_guid key_guid;
} __attribute__((packed));

#define EXPECTED_VB2_PACKED_KEY2_SIZE					\
	(EXPECTED_VB2_STRUCT_COMMON_SIZE + EXPECTED_GUID_SIZE + 16)

/* Current version of vb2_signature2 struct */
#define VB2_SIGNATURE2_VERSION_MAJOR 3
#define VB2_SIGNATURE2_VERSION_MINOR 0

/*
 * Signature data, version 2
 *
 * The signature data must be arranged like this:
 *     1) vb2_signature2 header struct h
 *     2) Signature description (pointed to by h.c.fixed_size)
 *     3) Signature data (pointed to by h.sig_offset)
 */
struct vb2_signature2 {
	/* Common header fields */
	struct vb2_struct_common c;

	/* Offset of signature data from start of this struct */
	uint32_t sig_offset;

	/* Size of signature data in bytes */
	uint32_t sig_size;

	/* Size of the data block which was signed in bytes */
	uint32_t data_size;

	/* Signature algorithm used (enum vb2_signature_algorithm) */
	uint16_t sig_alg;

	/* Hash digest algorithm used (enum vb2_hash_algorithm) */
	uint16_t hash_alg;

	/*
	 * GUID of key used to generate this signature.  This allows the
	 * firmware to quickly determine which signature block (if any) goes
	 * with the key being used by the firmware.
	 */
	struct vb2_guid key_guid;
} __attribute__((packed));

#define EXPECTED_VB2_SIGNATURE2_SIZE					\
	(EXPECTED_VB2_STRUCT_COMMON_SIZE + EXPECTED_GUID_SIZE + 16)


/* Current version of vb2_keyblock2 struct */
#define VB2_KEYBLOCK2_VERSION_MAJOR 3
#define VB2_KEYBLOCK2_VERSION_MINOR 0

/*
 * Key block.  This contains a signed, versioned key for use in the next stage
 * of verified boot.
 *
 * The key block data must be arranged like this:
 *     1) vb2_keyblock2 header struct h
 *     2) Keyblock description (pointed to by h.c.fixed_size)
 *     3) Data key (pointed to by h.data_key_offset)
 *     4) Signatures (first signature pointed to by h.sig_offset)
 *
 * The signatures from 4) must cover all the data from 1), 2), 3).  That is,
 * signatures must sign all data up to sig_offset.
 */
struct vb2_keyblock2 {
	/* Common header fields */
	struct vb2_struct_common c;

	/* Flags (VB2_KEY_BLOCK_FLAG_*) */
	uint32_t flags;

	/*
	 * Offset of key (struct vb2_packed_key2) to use in next stage of
	 * verification, from start of the keyblock.
	 */
	uint32_t key_offset;

	/* Number of keyblock signatures which follow */
	uint32_t sig_count;

	/*
	 * Offset of the first signature (struct vb2_signature2) from the start
	 * of the keyblock.
	 *
	 * Signatures sign the contents of this struct and the data pointed to
	 * by data_key_offset, but not themselves or other signatures.
	 *
	 * For the firmware, there may be only one signature.
	 *
	 * Kernels often have at least two signatures - one using the kernel
	 * subkey from the RW firmware (for signed kernels) and one which is
	 * simply a SHA-512 hash (for unsigned developer kernels).
	 */
	uint32_t sig_offset;
} __attribute__((packed));

#define EXPECTED_VB2_KEYBLOCK2_SIZE (EXPECTED_VB2_STRUCT_COMMON_SIZE + 16)


/* Current version of vb2_preamble2 struct */
#define VB2_PREAMBLE2_VERSION_MAJOR 3
#define VB2_PREAMBLE2_VERSION_MINOR 0

/* Single hash entry for the firmware preamble */
struct vb2_fw_preamble2_hash {
	/* Type of data being hashed (enum vb2api_hash_tag) */
	uint32_t tag;

	/* Size of hashed data in bytes */
	uint32_t data_size;

	/* Hash digest follows this struct */
	uint8_t digest[0];
} __attribute__((packed));

#define EXPECTED_VB2_FW_PREAMBLE2_HASH_SIZE 8

/*
 * Firmware preamble
 *
 * The preamble data must be arranged like this:
 *     1) vb2_fw_preamble2 header struct h
 *     2) Preamble description (pointed to by h.c.fixed_size)
 *     3) Hash table (pointed to by h.hash_table_offset)
 *     4) Signature (pointed to by h.sig_offset)
 *
 * The signature 4) must cover all the data from 1), 2), 3).
 */
struct vb2_fw_preamble2 {
	/* Common header fields */
	struct vb2_struct_common c;

	/* Flags; see VB2_FIRMWARE_PREAMBLE_* */
	uint32_t flags;

	/* Firmware version */
	uint32_t firmware_version;

	/* Offset of signature (struct vb2_signature2) for this preamble */
	uint32_t sig_offset;

	/*
	 * The preamble contains a list of hashes for the various firmware
	 * components.  The calling firmware is responsible for knowing where
	 * to find those components, which may be on a different storage device
	 * than this preamble.
	 */

	/* Number of hash entries */
	uint32_t hash_count;

	/*
	 * Hash algorithm used (must be same for all entries) (enum
	 * vb2_hash_algorithm).
	 */
	uint16_t hash_alg;

	/* Size of each hash entry, in bytes */
	uint16_t hash_entry_size;

	/*
	 * Offset of first hash entry from start of preamble.  Entry N can be
	 * found at:
	 *
	 * (uint8_t *)hdr + hdr->hash_table_offset + N * hdr->hash_entry_size
	 */
	uint32_t hash_table_offset;
} __attribute__((packed));

#define EXPECTED_VB2_FW_PREAMBLE2_SIZE (EXPECTED_VB2_STRUCT_COMMON_SIZE + 24)

/****************************************************************************/

/* Flags for vb2_shared_data.flags */
enum vb2_shared_data_flags {
	/* User has explicitly and physically requested recovery */
	VB2_SD_FLAG_MANUAL_RECOVERY = (1 << 0),

	/* Developer mode is enabled */
	VB2_SD_DEV_MODE_ENABLED = (1 << 1),

	/*
	 * TODO: might be nice to add flags for why dev mode is enabled - via
	 * gbb, virtual dev switch, or forced on for testing.
	 */
};

/* Flags for vb2_shared_data.status */
enum vb2_shared_data_status {
	/* Reinitialized NV data due to invalid checksum */
	VB2_SD_STATUS_NV_REINIT = (1 << 0),

	/* NV data has been initialized */
	VB2_SD_STATUS_NV_INIT = (1 << 1),

	/* Secure data initialized */
	VB2_SD_STATUS_SECDATA_INIT = (1 << 2),

	/* Chose a firmware slot */
	VB2_SD_STATUS_CHOSE_SLOT = (1 << 3),
};

/*
 * Data shared between vboot API calls.  Stored at the start of the work
 * buffer.
 */
struct vb2_shared_data {
	/* Flags; see enum vb2_shared_data_flags */
	uint32_t flags;

	/* Flags from GBB header */
	uint32_t gbb_flags;

	/*
	 * Reason we are in recovery mode this boot (enum vb2_nv_recovery), or
	 * 0 if we aren't.
	 */
	uint32_t recovery_reason;

	/* Firmware slot used last boot (0=A, 1=B) */
	uint32_t last_fw_slot;

	/* Result of last boot (enum vb2_fw_result) */
	uint32_t last_fw_result;

	/* Firmware slot used this boot */
	uint32_t fw_slot;

	/*
	 * Version for this slot (top 16 bits = key, lower 16 bits = firmware).
	 *
	 * TODO: Make this a union to allow getting/setting those versions
	 * separately?
	 */
	uint32_t fw_version;

	/*
	 * Status flags for this boot; see enum vb2_shared_data_status.  Status
	 * is "what we've done"; flags above are "decisions we've made".
	 */
	uint32_t status;

	/**********************************************************************
	 * Temporary variables used during firmware verification.  These don't
	 * really need to persist through to the OS, but there's nowhere else
	 * we can put them.
	 */

	/* Root key offset and size from GBB header */
	uint32_t gbb_rootkey_offset;
	uint32_t gbb_rootkey_size;

	/* Offset of preamble from start of vblock */
	uint32_t vblock_preamble_offset;

	/*
	 * Offset and size of packed data key in work buffer.  Size is 0 if
	 * data key is not stored in the work buffer.
	 */
	uint32_t workbuf_data_key_offset;
	uint32_t workbuf_data_key_size;

	/*
	 * Offset and size of firmware preamble in work buffer.  Size if 0 if
	 * preamble is not stored in the work buffer.
	 */
	uint32_t workbuf_preamble_offset;
	uint32_t workbuf_preamble_size;

	/*
	 * Offset and size of hash context in work buffer.  Size if 0 if
	 * hash context is not stored in the work buffer.
	 */
	uint32_t workbuf_hash_offset;
	uint32_t workbuf_hash_size;

	/* Current tag we're hashing */
	uint32_t hash_tag;

	/* Amount of data we still expect to hash */
	uint32_t hash_remaining_size;

} __attribute__((packed));

/****************************************************************************/

/* Signature at start of the GBB
 * Note that if you compile in the signature as is, you are likely to break any
 * tools that search for the signature. */
#define VB2_GBB_SIGNATURE "$GBB"
#define VB2_GBB_SIGNATURE_SIZE 4
#define VB2_GBB_XOR_CHARS "****"
/* TODO: can we write a macro to produce this at compile time? */
#define VB2_GBB_XOR_SIGNATURE { 0x0e, 0x6d, 0x68, 0x68 }

/* VB2 GBB struct version */
#define VB2_GBB_MAJOR_VER      1
#define VB2_GBB_MINOR_VER      2
/* v1.2 - added fields for sha256 digest of the HWID */

/* Flags for vb2_gbb_header.flags */
enum vb2_gbb_flag {
	/*
	 * Reduce the dev screen delay to 2 sec from 30 sec to speed up
	 * factory.
	 */
	VB2_GBB_FLAG_DEV_SCREEN_SHORT_DELAY = (1 << 0),

	/*
	 * BIOS should load option ROMs from arbitrary PCI devices. We'll never
	 * enable this ourselves because it executes non-verified code, but if
	 * a customer wants to void their warranty and set this flag in the
	 * read-only flash, they should be able to do so.
	 */
	VB2_GBB_FLAG_LOAD_OPTION_ROMS = (1 << 1),

	/*
	 * The factory flow may need the BIOS to boot a non-ChromeOS kernel if
	 * the dev-switch is on. This flag allows that.
	 */
	VB2_GBB_FLAG_ENABLE_ALTERNATE_OS = (1 << 2),

	/*
	 * Force dev switch on, regardless of physical/keyboard dev switch
	 * position.
	 */
	VB2_GBB_FLAG_FORCE_DEV_SWITCH_ON = (1 << 3),

	/* Allow booting from USB in dev mode even if dev_boot_usb=0. */
	VB2_GBB_FLAG_FORCE_DEV_BOOT_USB = (1 << 4),

	/* Disable firmware rollback protection. */
	VB2_GBB_FLAG_DISABLE_FW_ROLLBACK_CHECK = (1 << 5),

	/* Allow Enter key to trigger dev->tonorm screen transition */
	VB2_GBB_FLAG_ENTER_TRIGGERS_TONORM = (1 << 6),

	/* Allow booting Legacy OSes in dev mode even if dev_boot_legacy=0. */
	VB2_GBB_FLAG_FORCE_DEV_BOOT_LEGACY = (1 << 7),

	/* Allow booting using alternate keys for FAFT servo testing */
	VB2_GBB_FLAG_FAFT_KEY_OVERIDE = (1 << 8),

	/* Disable EC software sync */
	VB2_GBB_FLAG_DISABLE_EC_SOFTWARE_SYNC = (1 << 9),

	/* Default to booting legacy OS when dev screen times out */
	VB2_GBB_FLAG_DEFAULT_DEV_BOOT_LEGACY = (1 << 10),

	/* Disable PD software sync */
	VB2_GBB_FLAG_DISABLE_PD_SOFTWARE_SYNC = (1 << 11),
};

struct vb2_gbb_header {
	/* Fields present in version 1.1 */
	uint8_t  signature[VB2_GBB_SIGNATURE_SIZE]; /* VB2_GBB_SIGNATURE */
	uint16_t major_version;   /* See VB2_GBB_MAJOR_VER */
	uint16_t minor_version;   /* See VB2_GBB_MINOR_VER */
	uint32_t header_size;     /* Size of GBB header in bytes */
	uint32_t flags;           /* Flags (see enum vb2_gbb_flag) */

	/* Offsets (from start of header) and sizes (in bytes) of components */
	uint32_t hwid_offset;		/* HWID */
	uint32_t hwid_size;
	uint32_t rootkey_offset;	/* Root key */
	uint32_t rootkey_size;
	uint32_t bmpfv_offset;		/* BMP FV */
	uint32_t bmpfv_size;
	uint32_t recovery_key_offset;	/* Recovery key */
	uint32_t recovery_key_size;

	/* Added in version 1.2 */
	uint8_t  hwid_digest[32];	/* SHA-256 of HWID */

	/* Pad to match EXPECETED_VB2_GBB_HEADER_SIZE.  Initialize to 0. */
	uint8_t  pad[48];
} __attribute__((packed));

/* The GBB is used outside of vboot_reference, so this size is important. */
#define EXPECTED_VB2_GBB_HEADER_SIZE 128

#endif  /* VBOOT_REFERENCE_VBOOT_2STRUCT_H_ */