mirror of
https://github.com/Telecominfraproject/OpenCellular.git
synced 2025-11-24 02:05:01 +00:00
bcd8f4a07c
With this change, the kernel signature is a part of the preamble block (and therefore, used during preamble signature verification). BUG=670 TEST=image verification tests still pass. corrected splicing test expectations (and it passes). Review URL: http://codereview.chromium.org/2292001
203 lines
8.4 KiB
C
203 lines
8.4 KiB
C
/* 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.
|
|
*
|
|
* Data structure and API definitions for a verified boot kernel image.
|
|
* (Firmware Portion)
|
|
*/
|
|
|
|
#ifndef VBOOT_REFERENCE_KERNEL_IMAGE_FW_H_
|
|
#define VBOOT_REFERENCE_KERNEL_IMAGE_FW_H_
|
|
|
|
#include <stdint.h>
|
|
|
|
#include "cryptolib.h"
|
|
|
|
#define KERNEL_MAGIC "CHROMEOS"
|
|
#define KERNEL_MAGIC_SIZE 8
|
|
|
|
#define DEV_MODE_ENABLED 1
|
|
#define DEV_MODE_DISABLED 0
|
|
|
|
typedef struct KernelImage {
|
|
uint8_t magic[KERNEL_MAGIC_SIZE];
|
|
/* Key header */
|
|
uint16_t header_version; /* Header version. */
|
|
uint16_t header_len; /* Length of the header. */
|
|
uint16_t firmware_sign_algorithm; /* Signature algorithm used by the firmware
|
|
* signing key (used to sign this kernel
|
|
* header. */
|
|
uint16_t kernel_sign_algorithm; /* Signature algorithm used by the kernel
|
|
* signing key. */
|
|
uint16_t kernel_key_version; /* Key Version# for preventing rollbacks. */
|
|
uint8_t* kernel_sign_key; /* Pre-processed public half of signing key. */
|
|
/* TODO(gauravsh): Do we need a choice of digest algorithms for the header
|
|
* checksum? */
|
|
uint8_t header_checksum[SHA512_DIGEST_SIZE]; /* SHA-512 Crytographic hash of
|
|
* the concatenation of the
|
|
* header fields, i.e.
|
|
* [header_len,
|
|
* firmware_sign_algorithm,
|
|
* sign_algorithm, sign_key,
|
|
* key_version] */
|
|
/* End of kernel key header. */
|
|
uint8_t* kernel_key_signature; /* Signature of the header above. */
|
|
|
|
/* Kernel preamble */
|
|
uint16_t kernel_version; /* Kernel Version# for preventing rollbacks. */
|
|
uint64_t kernel_len; /* Length of the actual kernel image. */
|
|
uint64_t bootloader_offset; /* Offset of bootloader in kernel_data. */
|
|
uint64_t bootloader_size; /* Size of bootloader in bytes. */
|
|
uint64_t padded_header_size; /* start of kernel_data in disk partition */
|
|
uint8_t* kernel_signature; /* Signature on [kernel_data] below.
|
|
* NOTE: This is only considered valid
|
|
* if preamble_signature successfully verifies. */
|
|
/* end of preamble */
|
|
uint8_t* preamble_signature; /* signature on preamble, (includes
|
|
[kernel_signature]) */
|
|
uint8_t* kernel_data; /* Actual kernel data. */
|
|
|
|
} KernelImage;
|
|
|
|
/* Error Codes for VerifyFirmware. */
|
|
#define VERIFY_KERNEL_SUCCESS 0
|
|
#define VERIFY_KERNEL_INVALID_IMAGE 1
|
|
#define VERIFY_KERNEL_KEY_SIGNATURE_FAILED 2
|
|
#define VERIFY_KERNEL_INVALID_ALGORITHM 3
|
|
#define VERIFY_KERNEL_PREAMBLE_SIGNATURE_FAILED 4
|
|
#define VERIFY_KERNEL_SIGNATURE_FAILED 5
|
|
#define VERIFY_KERNEL_WRONG_MAGIC 6
|
|
#define VERIFY_KERNEL_MAX 7 /* Generic catch-all. */
|
|
|
|
extern char* kVerifyKernelErrors[VERIFY_KERNEL_MAX];
|
|
|
|
/* Returns the length of the verified boot kernel preamble based on
|
|
* kernel signing algorithm [algorithm]. */
|
|
uint64_t GetKernelPreambleLen(int algorithm);
|
|
|
|
/* Returns the length of the Kernel Verified Boot header excluding
|
|
* [kernel_data].
|
|
*
|
|
* This is always non-zero, so a return value of 0 signifies an error.
|
|
*/
|
|
uint64_t GetVBlockHeaderSize(const uint8_t* vkernel_blob);
|
|
|
|
/* Checks for the sanity of the kernel key header at [kernel_header_blob].
|
|
* If [dev_mode] is enabled, also checks the kernel key signature using the
|
|
* pre-processed public firmware signing key [firmware_sign_key_blob].
|
|
*
|
|
* On success, puts firmware signature algorithm in [firmware_algorithm],
|
|
* kernel signature algorithm in [kernel_algorithm], kernel header
|
|
* length in [header_len], and return 0.
|
|
* Else, return error code on failure.
|
|
*/
|
|
int VerifyKernelKeyHeader(const uint8_t* firmware_sign_key_blob,
|
|
const uint8_t* kernel_header_blob,
|
|
const int dev_mode,
|
|
int* firmware_algorithm,
|
|
int* kernel_algorithm,
|
|
int* header_len);
|
|
|
|
/* Checks the kernel preamble signature at [kernel_preamble_blob]
|
|
* using the signing key [kernel_sign_key].
|
|
*
|
|
* On success, put kernel length into [kernel_len], and return 0.
|
|
* Else, return error code on failure.
|
|
*/
|
|
int VerifyKernelPreamble(RSAPublicKey* kernel_sign_key,
|
|
const uint8_t* kernel_preamble_blob,
|
|
int algorithm,
|
|
uint64_t* kernel_len);
|
|
|
|
/* Checks [kernel_signature] on the kernel data at location [kernel_data]. The
|
|
* signature is assumed to be generated using algorithm [algorithm].
|
|
* The length of the kernel data is [kernel_len].
|
|
*
|
|
* Return 0 on success, error code on failure.
|
|
*/
|
|
int VerifyKernelData(RSAPublicKey* kernel_sign_key,
|
|
const uint8_t* kernel_signature,
|
|
const uint8_t* kernel_data,
|
|
uint64_t kernel_len,
|
|
int algorithm);
|
|
|
|
/* Verifies the kernel key header and preamble at [kernel_header_blob]
|
|
* using the firmware public key [firmware_key_blob]. If [dev_mode] is 1
|
|
* (active), then key header verification is skipped.
|
|
*
|
|
* Fills in a pointer to expected kernel data signature
|
|
* within [kernel_header_blob] in [expected_kernel_signature].
|
|
*
|
|
* The signing key to use for kernel data verification is returned in
|
|
* [kernel_sign_key], This must be free-d explicitly by the caller after use.
|
|
* The kernel signing algorithm is returned in [kernel_sign_algorithm] and its
|
|
* length in [kernel_len].
|
|
*
|
|
* Returns 0 on success, error code on failure.
|
|
*/
|
|
int VerifyKernelHeader(const uint8_t* firmware_key_blob,
|
|
const uint8_t* kernel_header_blob,
|
|
const int dev_mode,
|
|
const uint8_t** expected_kernel_signature,
|
|
RSAPublicKey** kernel_sign_key,
|
|
int* kernel_sign_algorithm,
|
|
uint64_t* kernel_len);
|
|
|
|
/* Performs a chained verify of the kernel blob [kernel_blob]. If
|
|
* [dev_mode] is 0 [inactive], then the pre-processed public signing key
|
|
* [root_key_blob] is used to verify the signature of the signing key,
|
|
* else the check is skipped.
|
|
*
|
|
*
|
|
* Returns 0 on success, error code on failure.
|
|
*
|
|
* NOTE: The length of the kernel blob is derived from reading the fields
|
|
* in the first few bytes of the buffer. This might look risky but in firmware
|
|
* land, the start address of the kernel_blob will always be fixed depending
|
|
* on the memory map on the particular platform. In addition, the signature on
|
|
* length itself is checked early in the verification process for extra safety.
|
|
*/
|
|
int VerifyKernel(const uint8_t* signing_key_blob,
|
|
const uint8_t* kernel_blob,
|
|
const int dev_mode);
|
|
|
|
/* Returns the logical version of a kernel blob which is calculated as
|
|
* (kernel_key_version << 16 | kernel_version). */
|
|
uint32_t GetLogicalKernelVersion(uint8_t* kernel_blob);
|
|
|
|
#define BOOT_KERNEL_A_CONTINUE 1
|
|
#define BOOT_KERNEL_B_CONTINUE 2
|
|
#define BOOT_KERNEL_RECOVERY_CONTINUE 3
|
|
|
|
/* Contains information about the kernel paritition
|
|
* gleaned from the GPT partition table.
|
|
*
|
|
* Based on the Chromium OS Drive Map design document by
|
|
* rspangler@chromium.org.
|
|
*
|
|
*/
|
|
typedef struct kernel_entry {
|
|
uint8_t* kernel_blob; /* Pointer to actual kernel. */
|
|
uint8_t boot_priority; /* 15 = highest, 1 = lowest, 0 = not bootable. */
|
|
uint8_t boot_tries_remaining; /* Used when boot_priority = 0. */
|
|
uint8_t boot_success_flag; /* Set to 1 on successful boot by AU. */
|
|
} kernel_entry;
|
|
|
|
/* This function is the driver used by the RW firmware to
|
|
* determine which copy of the kernel to boot from. It performs
|
|
* the requisite priority and remaining tries checking for a specific
|
|
* kernel partition, does rollback index checking, including updating
|
|
* if required.
|
|
*
|
|
* Returns the code path to follow. It is one of:
|
|
* BOOT_KERNEL_A_CONTINUE Boot from Kenrel A
|
|
* BOOT_KERNEL_B_CONTINUE Boot from Kernel B
|
|
* BOOT_KERNEL_RECOVERY_CONTINUE Jump to recovery mode
|
|
*/
|
|
int VerifyKernelDriver_f(uint8_t* firmware_key_blob,
|
|
kernel_entry* kernelA,
|
|
kernel_entry* kernelB,
|
|
int dev_mode);
|
|
|
|
#endif /* VBOOT_REFERENCE_KERNEL_IMAGE_FW_H_ */
|