Utility to pack public key, version, algorithm into a single file in VbPublicKey format

Review URL: http://codereview.chromium.org/2762009

host/lib/host_misc.c

@@ -0,0 +1,49 @@
+/* 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 functions for verified boot.
+ */
+
+/* TODO: change all 'return 0', 'return 1' into meaningful return codes */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "host_common.h"
+
+#include "cryptolib.h"
+#include "utility.h"
+#include "vboot_common.h"
+
+
+uint8_t* ReadFile(const char* filename, uint64_t* size) {
+  FILE* f;
+  uint8_t* buf;
+
+  f = fopen(filename, "rb");
+  if (!f) {
+    debug("Unable to open file %s\n", filename);
+    return NULL;
+  }
+
+  fseek(f, 0, SEEK_END);
+  *size = ftell(f);
+  rewind(f);
+
+  buf = Malloc(*size);
+  if (!buf) {
+    fclose(f);
+    return NULL;
+  }
+
+  if(1 != fread(buf, *size, 1, f)) {
+    debug("Unable to read from file %s\n", filename);
+    fclose(f);
+    Free(buf);
+    return NULL;
+  }
+
+  fclose(f);
+  return buf;
+}