Add --describe flag to {firmware|kernel}_utility.

src/platform/vboot_reference/include/kernel_image.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.
  *
  * Data structure and API definitions for a verified boot kernel image.
  */
 
 #ifndef VBOOT_REFERENCE_KERNEL_IMAGE_H_
 #define VBOOT_REFERENCE_KERNEL_IMAGE_H_
 
@@ skipping 62 matching lines @@
 
 /* Read kernel data from file named [input_file].
  *
  * Returns a filled up KernelImage on success, NULL on error.
  */
 KernelImage* ReadKernelImage(const char* input_file);
 
 /* Get the length of the header for kernel image [image]. */
 int GetKernelHeaderLen(const KernelImage* image);
 
+/* Calculate and store the kernel header checksum of [image]
+ * in [header_checksum].
+ *
+ * [header_checksum] must be a valid pointer to a buffer of
+ * SHA512_DIGEST_SIZE.
+ */
+void CalculateKernelHeaderChecksum(const KernelImage* image,
+                                   uint8_t* header_checksum);
+
 /* Get kernel header binary blob from an [image].
  *
  * Caller owns the returned pointer and must Free() it.
  */
 uint8_t* GetKernelHeaderBlob(const KernelImage* image);
 
 /* Get kernel config binary blob from an [image].
  *
  * Caller owns the returned pointer and must Free() it.
  */
@@ skipping 113 matching lines @@
 
 /* Add a kernel and kernel config signature to a kernel image [image]
  * using the private signing key in file [kernel_sigining_key_file].
  *
  * Return 1 on success, 0 on failure.
  */
 int AddKernelSignature(KernelImage* image,
                        const char* kernel_sigining_key_file);
 
 #endif  /* VBOOT_REFERENCE_KERNEL_IMAGE_H_ */