AU: Split applied update verification into a separate step.

install_plan.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.
 
 #ifndef CHROMEOS_PLATFORM_UPDATE_ENGINE_INSTALL_PLAN_H__
 #define CHROMEOS_PLATFORM_UPDATE_ENGINE_INSTALL_PLAN_H__
 
 #include <string>
 #include <vector>
 
@@ skipping 11 matching lines @@
               uint64_t size,
               const std::string& hash,
               const std::string& install_path,
               const std::string& kernel_install_path)
       : is_full_update(is_full),
         is_resume(is_resume),
         download_url(url),
         size(size),
         download_hash(hash),
         install_path(install_path),
-        kernel_install_path(kernel_install_path) {}
+        kernel_install_path(kernel_install_path),
+        kernel_size(0),
+        rootfs_size(0) {}
   InstallPlan() : is_full_update(false), is_resume(false), size(0) {}
 
   bool is_full_update;
   bool is_resume;
   std::string download_url;  // url to download from
   uint64_t size;  // size of the download url's data
   std::string download_hash;  // hash of the data at the url
   std::string install_path;  // path to install device
   std::string kernel_install_path;  // path to kernel install device
-  std::vector<char> current_kernel_hash;  // computed by FileSystemCopierAction
-  std::vector<char> current_rootfs_hash;  // computed by FileSystemCopierAction
+
+  // The fields below are used for kernel and rootfs verification. The flow is:
+  //
+  // 1. FilesystemCopierAction(verify_hash=false) computes and fills in the
+  // source partition sizes and hashes.
+  //
+  // 2. DownloadAction verifies the source partition sizes and hashes against
+  // the expected values transmitted in the update manifest. It fills in the
+  // expected applied partition sizes and hashes based on the manifest.
+  //
+  // 4. FilesystemCopierAction(verify_hashes=true) computes and verifies the
+  // applied partition sizes and hashes against the expected values.
+  uint64_t kernel_size;
+  uint64_t rootfs_size;
+  std::vector<char> kernel_hash;
+  std::vector<char> rootfs_hash;
 
   bool operator==(const InstallPlan& that) const {
     return (is_full_update == that.is_full_update) &&
         (is_resume == that.is_resume) &&
         (download_url == that.download_url) &&
         (size == that.size) &&
         (download_hash == that.download_hash) &&
         (install_path == that.install_path) &&
         (kernel_install_path == that.kernel_install_path);
   }
   bool operator!=(const InstallPlan& that) const {
     return !((*this) == that);
   }
   void Dump() const {
     LOG(INFO) << "InstallPlan: "
               << (is_full_update ? "full_update" : "delta_update")
               << (is_resume ? ", resume" : ", new_update")
               << ", url: " << download_url
               << ", size: " << size
               << ", hash: " << download_hash
               << ", install_path: " << install_path
               << ", kernel_install_path: " << kernel_install_path;
   }
 };
 
 }  // namespace chromeos_update_engine
 
 #endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_INSTALL_PLAN_H__