diff --git a/update_metadata.proto b/update_metadata.proto
index 213e740..40ba24f 100644
--- a/update_metadata.proto
+++ b/update_metadata.proto
@@ -1,4 +1,4 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -85,6 +85,11 @@
   repeated Signature signatures = 1;
 }
 
+message PartitionInfo {
+  optional uint64 size = 1;
+  optional bytes hash = 2;
+}
+
 message DeltaArchiveManifest {
   message InstallOperation {
     enum Type {
@@ -126,4 +131,10 @@
   // file.
   optional uint64 signatures_offset = 4;
   optional uint64 signatures_size = 5;
+
+  // Partition data that can be used to validate the update.
+  optional PartitionInfo old_kernel_info = 6;
+  optional PartitionInfo new_kernel_info = 7;
+  optional PartitionInfo old_rootfs_info = 8;
+  optional PartitionInfo new_rootfs_info = 9;
 }