Be less verbose while changing the password. Add a script for checking if password already exists.

Change-Id: Ia2b524e0bb2935d7acf220e78aebc65255cd26a2

BUG=chrome-os-partner:1564
TEST=manual

Review URL: http://codereview.chromium.org/5722004

scripts/image_signing/ensure_no_password.sh

@@ -0,0 +1,25 @@
+#!/bin/bash
+
+# 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.
+
+# abort on error
+set -e
+
+# Load common constants and variables.
+. "$(dirname "$0")/common.sh"
+
+if [ $# -ne 1 ]; then
+    echo "Usage $0 <image>"
+    exit 1
+fi
+
+IMAGE=$1
+ROOTFS=$(make_temp_dir)
+mount_image_partition_ro "$IMAGE" 3 "$ROOTFS"
+
+if ! no_chronos_password $rootfs; then
+    echo "chronos password is set! Shouldn't be for release builds."
+    exit 1
+fi

scripts/image_signing/set_chronos_password.sh

@@ -14,7 +14,7 @@
 change_chronos_password() {
   local rootfs=$1
   local password=$2
-  echo "Changing chronos password to '$password'..."
+  echo "Setting chronos password..."
   local crypted_password="$(echo $password | openssl passwd -1 -stdin)"
   local temp_shadow="$rootfs/etc/tempshadow"
   echo "chronos:$crypted_password:14500:0:99999::::" \
@@ -47,7 +47,7 @@ main() {
   mount_image_partition "$image" 3 "$rootfs"
   change_chronos_password "$rootfs" "$chronos_password"
   touch "$image"  # Updates the image modification time.
-  echo "Password Changed."
+  echo "Password Set."
 }
 
 main $@