Clean up of key block functions

host/include/host_keyblock.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.
+ *
+ * Host-side functions for verified boot.
+ */
+
+#ifndef VBOOT_REFERENCE_HOST_KEYBLOCK_H_
+#define VBOOT_REFERENCE_HOST_KEYBLOCK_H_
+
+#include <stdint.h>
+
+#include "host_key.h"
+#include "vboot_struct.h"
+
+
+/* Create a key block header containing [data_key] and [flags], signed
+ * by [signing_key].  Caller owns the returned pointer, and must free
+ * it with Free(). */
+VbKeyBlockHeader* KeyBlockCreate(const VbPublicKey* data_key,
+                                 const VbPrivateKey* signing_key,
+                                 uint64_t flags);
+
+
+/* Read a key block from a .keyblock file.  Caller owns the returned
+ * pointer, and must free it with Free().
+ *
+ * Returns NULL if error. */
+VbKeyBlockHeader* KeyBlockRead(const char* filename);
+
+
+/* Write a key block to a file in .keyblock format. */
+int KeyBlockWrite(const char* filename, const VbKeyBlockHeader* key_block);
+
+#endif  /* VBOOT_REFERENCE_HOST_KEYBLOCK_H_ */