diff --git a/Android.bp b/Android.bp
new file mode 100644
index 0000000..c3d164b
--- /dev/null
+++ b/Android.bp
@@ -0,0 +1,8 @@
+// AIDL interface between libupdate_engine and framework.jar
+filegroup {
+    name: "libupdate_engine_aidl",
+    srcs: [
+        "binder_bindings/android/os/IUpdateEngine.aidl",
+        "binder_bindings/android/os/IUpdateEngineCallback.aidl",
+    ],
+}
diff --git a/Android.mk b/Android.mk
index a3a7017..ddf633d 100644
--- a/Android.mk
+++ b/Android.mk
@@ -14,6 +14,8 @@
 # limitations under the License.
 #
 
+ifneq ($(TARGET_BUILD_PDK),true)
+
 LOCAL_PATH := $(my-dir)
 
 # Default values for the USE flags. Override these USE flags from your product
@@ -22,18 +24,18 @@
 local_use_binder := $(if $(BRILLO_USE_BINDER),$(BRILLO_USE_BINDER),1)
 local_use_hwid_override := \
     $(if $(BRILLO_USE_HWID_OVERRIDE),$(BRILLO_USE_HWID_OVERRIDE),0)
-# "libcros" gates the LibCrosService exposed by the Chrome OS' chrome browser to
-# the system layer.
-local_use_libcros := $(if $(BRILLO_USE_LIBCROS),$(BRILLO_USE_LIBCROS),0)
 local_use_mtd := $(if $(BRILLO_USE_MTD),$(BRILLO_USE_MTD),0)
+local_use_chrome_network_proxy := 0
+local_use_chrome_kiosk_app := 0
 
 # IoT devices use Omaha for updates.
 local_use_omaha := $(if $(filter true,$(PRODUCT_IOT)),1,0)
 
 ue_common_cflags := \
     -DUSE_BINDER=$(local_use_binder) \
+    -DUSE_CHROME_NETWORK_PROXY=$(local_use_chrome_network_proxy) \
+    -DUSE_CHROME_KIOSK_APP=$(local_use_chrome_kiosk_app) \
     -DUSE_HWID_OVERRIDE=$(local_use_hwid_override) \
-    -DUSE_LIBCROS=$(local_use_libcros) \
     -DUSE_MTD=$(local_use_mtd) \
     -DUSE_OMAHA=$(local_use_omaha) \
     -D_FILE_OFFSET_BITS=64 \
@@ -82,6 +84,7 @@
 generated_sources_dir := $(call local-generated-sources-dir)
 LOCAL_EXPORT_C_INCLUDE_DIRS := $(generated_sources_dir)/proto/system
 LOCAL_SRC_FILES := $(ue_update_metadata_protos_src_files)
+LOCAL_CFLAGS := -Wall -Werror
 include $(BUILD_HOST_STATIC_LIBRARY)
 
 # Build for the target.
@@ -91,6 +94,7 @@
 generated_sources_dir := $(call local-generated-sources-dir)
 LOCAL_EXPORT_C_INCLUDE_DIRS := $(generated_sources_dir)/proto/system
 LOCAL_SRC_FILES := $(ue_update_metadata_protos_src_files)
+LOCAL_CFLAGS := -Wall -Werror
 include $(BUILD_STATIC_LIBRARY)
 
 # libpayload_consumer (type: static_library)
@@ -101,6 +105,8 @@
     libxz \
     libbz \
     libbspatch \
+    libbrotli \
+    libpuffpatch \
     $(ue_update_metadata_protos_exported_static_libraries)
 ue_libpayload_consumer_exported_shared_libraries := \
     libcrypto \
@@ -125,10 +131,13 @@
     common/terminator.cc \
     common/utils.cc \
     payload_consumer/bzip_extent_writer.cc \
+    payload_consumer/cached_file_descriptor.cc \
     payload_consumer/delta_performer.cc \
     payload_consumer/download_action.cc \
+    payload_consumer/extent_reader.cc \
     payload_consumer/extent_writer.cc \
     payload_consumer/file_descriptor.cc \
+    payload_consumer/file_descriptor_utils.cc \
     payload_consumer/file_writer.cc \
     payload_consumer/filesystem_verifier_action.cc \
     payload_consumer/install_plan.cc \
@@ -143,7 +152,6 @@
 LOCAL_MODULE := libpayload_consumer
 LOCAL_MODULE_CLASS := STATIC_LIBRARIES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
@@ -167,7 +175,6 @@
 LOCAL_MODULE := libpayload_consumer
 LOCAL_MODULE_CLASS := STATIC_LIBRARIES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
@@ -203,7 +210,6 @@
 LOCAL_MODULE := libupdate_engine_boot_control
 LOCAL_MODULE_CLASS := STATIC_LIBRARIES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
@@ -261,7 +267,6 @@
 LOCAL_MODULE := libupdate_engine
 LOCAL_MODULE_CLASS := STATIC_LIBRARIES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_EXPORT_C_INCLUDE_DIRS := $(ue_libupdate_engine_exported_c_includes)
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
@@ -291,7 +296,7 @@
     hardware_android.cc \
     image_properties_android.cc \
     libcurl_http_fetcher.cc \
-    metrics.cc \
+    metrics_reporter_omaha.cc \
     metrics_utils.cc \
     omaha_request_action.cc \
     omaha_request_params.cc \
@@ -303,10 +308,15 @@
     proxy_resolver.cc \
     real_system_state.cc \
     update_attempter.cc \
+    update_manager/android_things_policy.cc \
+    update_manager/api_restricted_downloads_policy_impl.cc \
     update_manager/boxed_value.cc \
-    update_manager/chromeos_policy.cc \
     update_manager/default_policy.cc \
+    update_manager/enough_slots_ab_updates_policy_impl.cc \
     update_manager/evaluation_context.cc \
+    update_manager/interactive_update_policy_impl.cc \
+    update_manager/next_update_check_policy_impl.cc \
+    update_manager/official_build_check_policy_impl.cc \
     update_manager/policy.cc \
     update_manager/real_config_provider.cc \
     update_manager/real_device_policy_provider.cc \
@@ -326,10 +336,10 @@
     binder_service_brillo.cc \
     parcelable_update_engine_status.cc
 endif  # local_use_binder == 1
-ifeq ($(local_use_libcros),1)
+ifeq ($(local_use_chrome_network_proxy),1)
 LOCAL_SRC_FILES += \
     chrome_browser_proxy_resolver.cc
-endif  # local_use_libcros == 1
+endif  # local_use_chrome_network_proxy == 1
 include $(BUILD_STATIC_LIBRARY)
 
 else  # local_use_omaha == 1
@@ -359,6 +369,7 @@
     libbrillo-binder \
     libcutils \
     libcurl \
+    libmetricslogger \
     libssl \
     libutils
 
@@ -366,7 +377,6 @@
 LOCAL_MODULE := libupdate_engine_android
 LOCAL_MODULE_CLASS := STATIC_LIBRARIES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
@@ -393,6 +403,8 @@
     daemon_state_android.cc \
     hardware_android.cc \
     libcurl_http_fetcher.cc \
+    metrics_reporter_android.cc \
+    metrics_utils.cc \
     network_selector_android.cc \
     proxy_resolver.cc \
     update_attempter_android.cc \
@@ -411,7 +423,6 @@
 LOCAL_REQUIRED_MODULES := \
     cacerts_google
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
@@ -453,7 +464,6 @@
 LOCAL_MODULE_PATH := $(TARGET_RECOVERY_ROOT_OUT)/sbin
 LOCAL_MODULE_CLASS := EXECUTABLES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := \
     $(ue_common_cflags) \
     -D_UE_SIDELOAD
@@ -469,6 +479,8 @@
 LOCAL_SRC_FILES := \
     boot_control_recovery.cc \
     hardware_android.cc \
+    metrics_reporter_stub.cc \
+    metrics_utils.cc \
     network_selector_stub.cc \
     proxy_resolver.cc \
     sideload_main.cc \
@@ -489,7 +501,7 @@
 # library dependencies of these static libraries.
 LOCAL_STATIC_LIBRARIES += \
     $(ue_common_shared_libraries) \
-    libcutils \
+    libbase \
     liblog \
     $(ue_libpayload_consumer_exported_shared_libraries:-host=) \
     $(ue_update_metadata_protos_exported_shared_libraries) \
@@ -522,7 +534,6 @@
     -Werror \
     -Wno-unused-parameter \
     -DUSE_BINDER=$(local_use_binder)
-LOCAL_CLANG := true
 LOCAL_CPP_EXTENSION := .cc
 # TODO(deymo): Remove "external/cros/system_api/dbus" when dbus is not used.
 LOCAL_C_INCLUDES := \
@@ -560,7 +571,6 @@
 LOCAL_MODULE := update_engine_client
 LOCAL_MODULE_CLASS := EXECUTABLES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
@@ -599,9 +609,14 @@
 # server-side code. This is used for delta_generator and unittests but not
 # for any client code.
 ue_libpayload_generator_exported_static_libraries := \
-    libpayload_consumer \
-    update_metadata-protos \
+    libbsdiff \
+    libdivsufsort \
+    libdivsufsort64 \
+    libbrotli \
     liblzma \
+    libpayload_consumer \
+    libpuffdiff \
+    update_metadata-protos \
     $(ue_libpayload_consumer_exported_static_libraries) \
     $(ue_update_metadata_protos_exported_static_libraries)
 ue_libpayload_generator_exported_shared_libraries := \
@@ -616,6 +631,7 @@
     payload_generator/block_mapping.cc \
     payload_generator/bzip.cc \
     payload_generator/cycle_breaker.cc \
+    payload_generator/deflate_utils.cc \
     payload_generator/delta_diff_generator.cc \
     payload_generator/delta_diff_utils.cc \
     payload_generator/ext2_filesystem.cc \
@@ -630,6 +646,7 @@
     payload_generator/payload_generation_config.cc \
     payload_generator/payload_signer.cc \
     payload_generator/raw_filesystem.cc \
+    payload_generator/squashfs_filesystem.cc \
     payload_generator/tarjan.cc \
     payload_generator/topological_sort.cc \
     payload_generator/xz_android.cc
@@ -640,15 +657,18 @@
 LOCAL_MODULE := libpayload_generator
 LOCAL_MODULE_CLASS := STATIC_LIBRARIES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
 LOCAL_C_INCLUDES := $(ue_common_c_includes)
 LOCAL_STATIC_LIBRARIES := \
-    libpayload_consumer \
-    update_metadata-protos \
+    libbsdiff \
+    libdivsufsort \
+    libdivsufsort64 \
     liblzma \
+    libpayload_consumer \
+    libpuffdiff \
+    update_metadata-protos \
     $(ue_common_static_libraries) \
     $(ue_libpayload_consumer_exported_static_libraries) \
     $(ue_update_metadata_protos_exported_static_libraries)
@@ -666,12 +686,14 @@
 LOCAL_MODULE := libpayload_generator
 LOCAL_MODULE_CLASS := STATIC_LIBRARIES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
 LOCAL_C_INCLUDES := $(ue_common_c_includes)
 LOCAL_STATIC_LIBRARIES := \
+    libbsdiff \
+    libdivsufsort \
+    libdivsufsort64 \
     libpayload_consumer \
     update_metadata-protos \
     liblzma \
@@ -696,12 +718,8 @@
 # Build for the host.
 include $(CLEAR_VARS)
 LOCAL_MODULE := delta_generator
-LOCAL_REQUIRED_MODULES := \
-    bsdiff \
-    imgdiff
 LOCAL_MODULE_CLASS := EXECUTABLES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
@@ -727,7 +745,6 @@
 LOCAL_MODULE_STEM := delta_generator
 LOCAL_MODULE_CLASS := EXECUTABLES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
@@ -802,15 +819,6 @@
 $(call ue-unittest-sample-image,disk_ext2_4k_empty.img)
 $(call ue-unittest-sample-image,disk_ext2_unittest.img)
 
-# Zlib Fingerprint
-# ========================================================
-include $(CLEAR_VARS)
-LOCAL_MODULE := zlib_fingerprint
-LOCAL_MODULE_CLASS := ETC
-LOCAL_MODULE_PATH := $(TARGET_OUT_DATA_NATIVE_TESTS)/update_engine_unittests
-LOCAL_PREBUILT_MODULE_FILE := $(TARGET_OUT_COMMON_GEN)/zlib_fingerprint
-include $(BUILD_PREBUILT)
-
 # update_engine.conf
 # ========================================================
 include $(CLEAR_VARS)
@@ -829,7 +837,6 @@
 LOCAL_MODULE_PATH := $(TARGET_OUT_DATA_NATIVE_TESTS)/update_engine_unittests
 LOCAL_MODULE_CLASS := EXECUTABLES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
@@ -841,28 +848,6 @@
     test_http_server.cc
 include $(BUILD_EXECUTABLE)
 
-# bsdiff (type: executable)
-# ========================================================
-# We need bsdiff in the update_engine_unittests directory, so we build it here.
-include $(CLEAR_VARS)
-LOCAL_MODULE := ue_unittest_bsdiff
-LOCAL_MODULE_PATH := $(TARGET_OUT_DATA_NATIVE_TESTS)/update_engine_unittests
-LOCAL_MODULE_STEM := bsdiff
-LOCAL_CPP_EXTENSION := .cc
-LOCAL_SRC_FILES := ../../external/bsdiff/bsdiff_main.cc
-LOCAL_CFLAGS := \
-    -D_FILE_OFFSET_BITS=64 \
-    -Wall \
-    -Werror \
-    -Wextra \
-    -Wno-unused-parameter
-LOCAL_STATIC_LIBRARIES := \
-    libbsdiff \
-    libbz \
-    libdivsufsort64 \
-    libdivsufsort
-include $(BUILD_EXECUTABLE)
-
 # test_subprocess (type: executable)
 # ========================================================
 # Test helper subprocess program.
@@ -871,7 +856,6 @@
 LOCAL_MODULE_PATH := $(TARGET_OUT_DATA_NATIVE_TESTS)/update_engine_unittests
 LOCAL_MODULE_CLASS := EXECUTABLES
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
@@ -889,7 +873,6 @@
 LOCAL_REQUIRED_MODULES := \
     test_http_server \
     test_subprocess \
-    ue_unittest_bsdiff \
     ue_unittest_delta_generator \
     ue_unittest_disk_ext2_1k.img \
     ue_unittest_disk_ext2_4k.img \
@@ -899,10 +882,8 @@
     ue_unittest_key.pub.pem \
     ue_unittest_key2.pem \
     ue_unittest_key2.pub.pem \
-    ue_unittest_update_engine.conf \
-    zlib_fingerprint
+    ue_unittest_update_engine.conf
 LOCAL_CPP_EXTENSION := .cc
-LOCAL_CLANG := true
 LOCAL_CFLAGS := $(ue_common_cflags)
 LOCAL_CPPFLAGS := $(ue_common_cppflags)
 LOCAL_LDFLAGS := $(ue_common_ldflags)
@@ -937,9 +918,13 @@
     common/test_utils.cc \
     common/utils_unittest.cc \
     payload_consumer/bzip_extent_writer_unittest.cc \
+    payload_consumer/cached_file_descriptor_unittest.cc \
     payload_consumer/delta_performer_integration_test.cc \
     payload_consumer/delta_performer_unittest.cc \
+    payload_consumer/extent_reader_unittest.cc \
     payload_consumer/extent_writer_unittest.cc \
+    payload_consumer/fake_file_descriptor.cc \
+    payload_consumer/file_descriptor_utils_unittest.cc \
     payload_consumer/file_writer_unittest.cc \
     payload_consumer/filesystem_verifier_action_unittest.cc \
     payload_consumer/postinstall_runner_action_unittest.cc \
@@ -948,6 +933,7 @@
     payload_generator/blob_file_writer_unittest.cc \
     payload_generator/block_mapping_unittest.cc \
     payload_generator/cycle_breaker_unittest.cc \
+    payload_generator/deflate_utils_unittest.cc \
     payload_generator/delta_diff_utils_unittest.cc \
     payload_generator/ext2_filesystem_unittest.cc \
     payload_generator/extent_ranges_unittest.cc \
@@ -960,6 +946,7 @@
     payload_generator/payload_file_unittest.cc \
     payload_generator/payload_generation_config_unittest.cc \
     payload_generator/payload_signer_unittest.cc \
+    payload_generator/squashfs_filesystem_unittest.cc \
     payload_generator/tarjan_unittest.cc \
     payload_generator/topological_sort_unittest.cc \
     payload_generator/zip_unittest.cc \
@@ -977,6 +964,7 @@
     common_service_unittest.cc \
     fake_system_state.cc \
     image_properties_android_unittest.cc \
+    metrics_reporter_omaha_unittest.cc \
     metrics_utils_unittest.cc \
     omaha_request_action_unittest.cc \
     omaha_request_params_unittest.cc \
@@ -985,11 +973,16 @@
     p2p_manager_unittest.cc \
     payload_consumer/download_action_unittest.cc \
     payload_state_unittest.cc \
+    parcelable_update_engine_status_unittest.cc \
     update_attempter_unittest.cc \
+    update_manager/android_things_policy_unittest.cc \
     update_manager/boxed_value_unittest.cc \
+    update_manager/chromeos_policy.cc \
     update_manager/chromeos_policy_unittest.cc \
     update_manager/evaluation_context_unittest.cc \
     update_manager/generic_variables_unittest.cc \
+    update_manager/next_update_check_policy_impl_unittest.cc \
+    update_manager/policy_test_utils.cc \
     update_manager/prng_unittest.cc \
     update_manager/real_device_policy_provider_unittest.cc \
     update_manager/real_random_provider_unittest.cc \
@@ -1005,11 +998,9 @@
     $(ue_libupdate_engine_android_exported_static_libraries:-host=)
 LOCAL_SHARED_LIBRARIES += \
     $(ue_libupdate_engine_android_exported_shared_libraries:-host=)
-endif  # local_use_omaha == 1
-ifeq ($(local_use_libcros),1)
 LOCAL_SRC_FILES += \
-    chrome_browser_proxy_resolver_unittest.cc
-endif  # local_use_libcros == 1
+    update_attempter_android_unittest.cc
+endif  # local_use_omaha == 1
 include $(BUILD_NATIVE_TEST)
 
 # Update payload signing public key.
@@ -1036,6 +1027,9 @@
 LOCAL_MODULE_TAGS := optional
 LOCAL_REQUIRED_MODULES := \
     delta_generator \
-    shflags
+    shflags \
+    simg2img
 include $(BUILD_PREBUILT)
 endif  # HOST_OS == linux
+
+endif  # ifneq ($(TARGET_BUILD_PDK),true)
diff --git a/COMMIT-QUEUE.ini b/COMMIT-QUEUE.ini
new file mode 100644
index 0000000..ed99b9f
--- /dev/null
+++ b/COMMIT-QUEUE.ini
@@ -0,0 +1,11 @@
+# Copyright 2017 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.
+
+# Per-project Commit Queue settings.
+# Documentation: http://goo.gl/5J7oND
+
+[GENERAL]
+
+# Moblab testing is needed because of the udpate_payloads ebuild.
+pre-cq-configs: default guado_moblab-no-vmtest-pre-cq
diff --git a/CPPLINT.cfg b/CPPLINT.cfg
new file mode 100644
index 0000000..3dd0f35
--- /dev/null
+++ b/CPPLINT.cfg
@@ -0,0 +1,3 @@
+# This should be kept in sync with platform2/CPPLINT.cfg
+set noparent
+filter=-build/include_order,+build/include_alpha,-build/header_guard
diff --git a/OWNERS b/OWNERS
index f64bd32..0bf7587 100644
--- a/OWNERS
+++ b/OWNERS
@@ -6,3 +6,4 @@
 
 # Chromium OS maintainers:
 benchan@google.com
+ahassani@google.com
diff --git a/PRESUBMIT.cfg b/PRESUBMIT.cfg
index 087dfa3..3b8b271 100644
--- a/PRESUBMIT.cfg
+++ b/PRESUBMIT.cfg
@@ -1,3 +1,7 @@
+[Hook Scripts]
+hook0=../../../../chromite/bin/cros lint ${PRESUBMIT_FILES}
+hook1=../../../platform2/common-mk/gyplint.py ${PRESUBMIT_FILES}
+
 [Hook Overrides]
 cros_license_check: false
 aosp_license_check: true
diff --git a/PREUPLOAD.cfg b/PREUPLOAD.cfg
index 706dfa8..40ddcd1 100644
--- a/PREUPLOAD.cfg
+++ b/PREUPLOAD.cfg
@@ -1,3 +1,4 @@
 [Builtin Hooks]
 clang_format = true
+cpplint = true
 pylint = true
diff --git a/binder_bindings/android/brillo/IUpdateEngine.aidl b/binder_bindings/android/brillo/IUpdateEngine.aidl
index b1a1b4f..e549a4d 100644
--- a/binder_bindings/android/brillo/IUpdateEngine.aidl
+++ b/binder_bindings/android/brillo/IUpdateEngine.aidl
@@ -20,7 +20,8 @@
 import android.brillo.ParcelableUpdateEngineStatus;
 
 interface IUpdateEngine {
-  void AttemptUpdate(in String app_version, in String omaha_url, in int flags);
+  void SetUpdateAttemptFlags(in int flags);
+  boolean AttemptUpdate(in String app_version, in String omaha_url, in int flags);
   void AttemptRollback(in boolean powerwash);
   boolean CanRollback();
   void ResetStatus();
diff --git a/binder_bindings/android/brillo/IUpdateEngineStatusCallback.aidl b/binder_bindings/android/brillo/IUpdateEngineStatusCallback.aidl
index 42b6438..837d44d 100644
--- a/binder_bindings/android/brillo/IUpdateEngineStatusCallback.aidl
+++ b/binder_bindings/android/brillo/IUpdateEngineStatusCallback.aidl
@@ -16,8 +16,9 @@
 
 package android.brillo;
 
+import android.brillo.ParcelableUpdateEngineStatus;
+
 interface IUpdateEngineStatusCallback {
   oneway
-  void HandleStatusUpdate(in long last_checked_time, in double progress,
-      in String current_operation, in String new_version, in long new_size);
+  void HandleStatusUpdate(in ParcelableUpdateEngineStatus status);
 }
diff --git a/binder_service_android.cc b/binder_service_android.cc
index e179c62..0305727 100644
--- a/binder_service_android.cc
+++ b/binder_service_android.cc
@@ -24,6 +24,7 @@
 
 using android::binder::Status;
 using android::os::IUpdateEngineCallback;
+using update_engine::UpdateEngineStatus;
 
 namespace {
 Status ErrorPtrToStatus(const brillo::ErrorPtr& error) {
@@ -40,13 +41,9 @@
 }
 
 void BinderUpdateEngineAndroidService::SendStatusUpdate(
-    int64_t /* last_checked_time */,
-    double progress,
-    update_engine::UpdateStatus status,
-    const std::string& /* new_version  */,
-    int64_t /* new_size */) {
-  last_status_ = static_cast<int>(status);
-  last_progress_ = progress;
+    const UpdateEngineStatus& update_engine_status) {
+  last_status_ = static_cast<int>(update_engine_status.status);
+  last_progress_ = update_engine_status.progress;
   for (auto& callback : callbacks_) {
     callback->onStatusUpdate(last_status_, last_progress_);
   }
diff --git a/binder_service_android.h b/binder_service_android.h
index 7d66fcc..eb36e4c 100644
--- a/binder_service_android.h
+++ b/binder_service_android.h
@@ -45,11 +45,8 @@
   }
 
   // ServiceObserverInterface overrides.
-  void SendStatusUpdate(int64_t last_checked_time,
-                        double progress,
-                        update_engine::UpdateStatus status,
-                        const std::string& new_version,
-                        int64_t new_size) override;
+  void SendStatusUpdate(
+      const update_engine::UpdateEngineStatus& update_engine_status) override;
   void SendPayloadApplicationComplete(ErrorCode error_code) override;
 
   // android::os::BnUpdateEngine overrides.
diff --git a/binder_service_brillo.cc b/binder_service_brillo.cc
index 5e74159..3f01e42 100644
--- a/binder_service_brillo.cc
+++ b/binder_service_brillo.cc
@@ -33,6 +33,7 @@
 using android::sp;
 using brillo::ErrorPtr;
 using std::string;
+using update_engine::UpdateEngineStatus;
 
 namespace chromeos_update_engine {
 
@@ -57,12 +58,20 @@
   return ToStatus(&error);
 }
 
+Status BinderUpdateEngineBrilloService::SetUpdateAttemptFlags(int flags) {
+  return CallCommonHandler(&UpdateEngineService::SetUpdateAttemptFlags, flags);
+}
+
 Status BinderUpdateEngineBrilloService::AttemptUpdate(
-    const String16& app_version, const String16& omaha_url, int flags) {
+    const String16& app_version,
+    const String16& omaha_url,
+    int flags,
+    bool* out_result) {
   return CallCommonHandler(&UpdateEngineService::AttemptUpdate,
                            NormalString(app_version),
                            NormalString(omaha_url),
-                           flags);
+                           flags,
+                           out_result);
 }
 
 Status BinderUpdateEngineBrilloService::AttemptRollback(bool powerwash) {
@@ -79,19 +88,12 @@
 
 Status BinderUpdateEngineBrilloService::GetStatus(
     ParcelableUpdateEngineStatus* status) {
-  string current_op;
-  string new_version;
-
-  auto ret = CallCommonHandler(&UpdateEngineService::GetStatus,
-                               &status->last_checked_time_,
-                               &status->progress_,
-                               &current_op,
-                               &new_version,
-                               &status->new_size_);
+  UpdateEngineStatus update_engine_status;
+  auto ret =
+      CallCommonHandler(&UpdateEngineService::GetStatus, &update_engine_status);
 
   if (ret.isOk()) {
-    status->current_operation_ = String16{current_op.c_str()};
-    status->new_version_ = String16{new_version.c_str()};
+    *status = ParcelableUpdateEngineStatus(update_engine_status);
   }
 
   return ret;
@@ -228,18 +230,10 @@
 }
 
 void BinderUpdateEngineBrilloService::SendStatusUpdate(
-    int64_t last_checked_time,
-    double progress,
-    update_engine::UpdateStatus status,
-    const string& new_version,
-    int64_t new_size) {
-  const string str_status = UpdateStatusToString(status);
+    const UpdateEngineStatus& update_engine_status) {
+  ParcelableUpdateEngineStatus parcelable_status(update_engine_status);
   for (auto& callback : callbacks_) {
-    callback->HandleStatusUpdate(last_checked_time,
-                                 progress,
-                                 String16{str_status.c_str()},
-                                 String16{new_version.c_str()},
-                                 new_size);
+    callback->HandleStatusUpdate(parcelable_status);
   }
 }
 
diff --git a/binder_service_brillo.h b/binder_service_brillo.h
index 982c7b1..c802fca 100644
--- a/binder_service_brillo.h
+++ b/binder_service_brillo.h
@@ -46,17 +46,16 @@
   }
 
   // ServiceObserverInterface overrides.
-  void SendStatusUpdate(int64_t last_checked_time,
-                        double progress,
-                        update_engine::UpdateStatus status,
-                        const std::string& new_version,
-                        int64_t new_size) override;
+  void SendStatusUpdate(
+      const update_engine::UpdateEngineStatus& update_engine_status) override;
   void SendPayloadApplicationComplete(ErrorCode error_code) override {}
 
   // android::brillo::BnUpdateEngine overrides.
+  android::binder::Status SetUpdateAttemptFlags(int flags) override;
   android::binder::Status AttemptUpdate(const android::String16& app_version,
                                         const android::String16& omaha_url,
-                                        int flags) override;
+                                        int flags,
+                                        bool* out_result) override;
   android::binder::Status AttemptRollback(bool powerwash) override;
   android::binder::Status CanRollback(bool* out_can_rollback) override;
   android::binder::Status ResetStatus() override;
diff --git a/boot_control_android.cc b/boot_control_android.cc
index e3ea66d..8c1603b 100644
--- a/boot_control_android.cc
+++ b/boot_control_android.cc
@@ -20,7 +20,6 @@
 #include <base/files/file_util.h>
 #include <base/logging.h>
 #include <base/strings/string_util.h>
-#include <brillo/make_unique_ptr.h>
 #include <brillo/message_loops/message_loop.h>
 
 #include "update_engine/common/utils.h"
diff --git a/boot_control_chromeos.cc b/boot_control_chromeos.cc
index e9ad698..aa94d3c 100644
--- a/boot_control_chromeos.cc
+++ b/boot_control_chromeos.cc
@@ -22,7 +22,6 @@
 #include <base/files/file_path.h>
 #include <base/files/file_util.h>
 #include <base/strings/string_util.h>
-#include <brillo/make_unique_ptr.h>
 #include <rootdev/rootdev.h>
 
 extern "C" {
diff --git a/boot_control_recovery.cc b/boot_control_recovery.cc
index 39b5ff1..b74f4aa 100644
--- a/boot_control_recovery.cc
+++ b/boot_control_recovery.cc
@@ -20,7 +20,6 @@
 #include <base/files/file_util.h>
 #include <base/logging.h>
 #include <base/strings/string_util.h>
-#include <brillo/make_unique_ptr.h>
 #include <brillo/message_loops/message_loop.h>
 
 #include "update_engine/common/utils.h"
diff --git a/certificate_checker_unittest.cc b/certificate_checker_unittest.cc
index 20efce9..66b92d6 100644
--- a/certificate_checker_unittest.cc
+++ b/certificate_checker_unittest.cc
@@ -29,7 +29,7 @@
 
 using ::testing::DoAll;
 using ::testing::Return;
-using ::testing::SetArgumentPointee;
+using ::testing::SetArgPointee;
 using ::testing::SetArrayArgument;
 using ::testing::_;
 using std::string;
@@ -78,8 +78,8 @@
 TEST_F(CertificateCheckerTest, NewCertificate) {
   EXPECT_CALL(openssl_wrapper_, GetCertificateDigest(nullptr, _, _, _))
       .WillOnce(DoAll(
-          SetArgumentPointee<1>(depth_),
-          SetArgumentPointee<2>(length_),
+          SetArgPointee<1>(depth_),
+          SetArgPointee<2>(length_),
           SetArrayArgument<3>(digest_, digest_ + 4),
           Return(true)));
   EXPECT_CALL(prefs_, GetString(cert_key_, _)).WillOnce(Return(false));
@@ -95,12 +95,12 @@
 TEST_F(CertificateCheckerTest, SameCertificate) {
   EXPECT_CALL(openssl_wrapper_, GetCertificateDigest(nullptr, _, _, _))
       .WillOnce(DoAll(
-          SetArgumentPointee<1>(depth_),
-          SetArgumentPointee<2>(length_),
+          SetArgPointee<1>(depth_),
+          SetArgPointee<2>(length_),
           SetArrayArgument<3>(digest_, digest_ + 4),
           Return(true)));
   EXPECT_CALL(prefs_, GetString(cert_key_, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(digest_hex_), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(digest_hex_), Return(true)));
   EXPECT_CALL(prefs_, SetString(_, _)).Times(0);
   EXPECT_CALL(observer_,
               CertificateChecked(server_to_check_,
@@ -113,12 +113,12 @@
 TEST_F(CertificateCheckerTest, ChangedCertificate) {
   EXPECT_CALL(openssl_wrapper_, GetCertificateDigest(nullptr, _, _, _))
       .WillOnce(DoAll(
-          SetArgumentPointee<1>(depth_),
-          SetArgumentPointee<2>(length_),
+          SetArgPointee<1>(depth_),
+          SetArgPointee<2>(length_),
           SetArrayArgument<3>(digest_, digest_ + 4),
           Return(true)));
   EXPECT_CALL(prefs_, GetString(cert_key_, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(diff_digest_hex_), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(diff_digest_hex_), Return(true)));
   EXPECT_CALL(observer_,
               CertificateChecked(server_to_check_,
                                  CertificateCheckResult::kValidChanged));
diff --git a/chrome_browser_proxy_resolver.cc b/chrome_browser_proxy_resolver.cc
index 12a8328..5beecc1 100644
--- a/chrome_browser_proxy_resolver.cc
+++ b/chrome_browser_proxy_resolver.cc
@@ -20,85 +20,26 @@
 
 #include <base/bind.h>
 #include <base/memory/ptr_util.h>
-#include <base/strings/string_tokenizer.h>
 #include <base/strings/string_util.h>
+#include <brillo/http/http_proxy.h>
 
-#include "network_proxy/dbus-proxies.h"
+#include "update_engine/dbus_connection.h"
 
 namespace chromeos_update_engine {
 
-using base::StringTokenizer;
-using std::deque;
-using std::string;
-
-namespace {
-
-// Timeout for D-Bus calls in milliseconds.
-constexpr int kTimeoutMs = 5000;
-
-}  // namespace
-
-ChromeBrowserProxyResolver::ChromeBrowserProxyResolver(
-    org::chromium::NetworkProxyServiceInterfaceProxyInterface* dbus_proxy)
-    : dbus_proxy_(dbus_proxy),
-      next_request_id_(kProxyRequestIdNull + 1),
+ChromeBrowserProxyResolver::ChromeBrowserProxyResolver()
+    : next_request_id_(kProxyRequestIdNull + 1),
       weak_ptr_factory_(this) {}
 
 ChromeBrowserProxyResolver::~ChromeBrowserProxyResolver() = default;
 
-// static
-deque<string> ChromeBrowserProxyResolver::ParseProxyString(
-    const string& input) {
-  deque<string> ret;
-  // Some of this code taken from
-  // http://src.chromium.org/svn/trunk/src/net/proxy/proxy_server.cc and
-  // http://src.chromium.org/svn/trunk/src/net/proxy/proxy_list.cc
-  StringTokenizer entry_tok(input, ";");
-  while (entry_tok.GetNext()) {
-    string token = entry_tok.token();
-    base::TrimWhitespaceASCII(token, base::TRIM_ALL, &token);
-
-    // Start by finding the first space (if any).
-    string::iterator space;
-    for (space = token.begin(); space != token.end(); ++space) {
-      if (base::IsAsciiWhitespace(*space)) {
-        break;
-      }
-    }
-
-    string scheme = base::ToLowerASCII(string(token.begin(), space));
-    // Chrome uses "socks" to mean socks4 and "proxy" to mean http.
-    if (scheme == "socks")
-      scheme += "4";
-    else if (scheme == "proxy")
-      scheme = "http";
-    else if (scheme != "https" &&
-             scheme != "socks4" &&
-             scheme != "socks5" &&
-             scheme != "direct")
-      continue;  // Invalid proxy scheme
-
-    string host_and_port = string(space, token.end());
-    base::TrimWhitespaceASCII(host_and_port, base::TRIM_ALL, &host_and_port);
-    if (scheme != "direct" && host_and_port.empty())
-      continue;  // Must supply host/port when non-direct proxy used.
-    ret.push_back(scheme + "://" + host_and_port);
-  }
-  if (ret.empty() || *ret.rbegin() != kNoProxy)
-    ret.push_back(kNoProxy);
-  return ret;
-}
-
 ProxyRequestId ChromeBrowserProxyResolver::GetProxiesForUrl(
-    const string& url, const ProxiesResolvedFn& callback) {
+    const std::string& url, const ProxiesResolvedFn& callback) {
   const ProxyRequestId id = next_request_id_++;
-  dbus_proxy_->ResolveProxyAsync(
-      url,
-      base::Bind(&ChromeBrowserProxyResolver::OnResolveProxyResponse,
-                 weak_ptr_factory_.GetWeakPtr(), id),
-      base::Bind(&ChromeBrowserProxyResolver::OnResolveProxyError,
-                 weak_ptr_factory_.GetWeakPtr(), id),
-      kTimeoutMs);
+  brillo::http::GetChromeProxyServersAsync(
+      DBusConnection::Get()->GetDBus(), url,
+      base::Bind(&ChromeBrowserProxyResolver::OnGetChromeProxyServers,
+                 weak_ptr_factory_.GetWeakPtr(), id));
   pending_callbacks_[id] = callback;
   return id;
 }
@@ -107,32 +48,18 @@
   return pending_callbacks_.erase(request) != 0;
 }
 
-void ChromeBrowserProxyResolver::OnResolveProxyResponse(
-    ProxyRequestId request_id,
-    const std::string& proxy_info,
-    const std::string& error_message) {
-  if (!error_message.empty())
-    LOG(WARNING) << "Got error resolving proxy: " << error_message;
-  RunCallback(request_id, ParseProxyString(proxy_info));
-}
-
-void ChromeBrowserProxyResolver::OnResolveProxyError(ProxyRequestId request_id,
-                                                     brillo::Error* error) {
-  LOG(WARNING) << "Failed to resolve proxy: "
-               << (error ? error->GetMessage() : "[null]");
-  RunCallback(request_id, deque<string>{kNoProxy});
-}
-
-void ChromeBrowserProxyResolver::RunCallback(
-    ProxyRequestId request_id,
-    const std::deque<std::string>& proxies) {
+void ChromeBrowserProxyResolver::OnGetChromeProxyServers(
+    ProxyRequestId request_id, bool success,
+    const std::vector<std::string>& proxies) {
+  // If |success| is false, |proxies| will still hold the direct proxy option
+  // which is what we do in our error case.
   auto it = pending_callbacks_.find(request_id);
   if (it == pending_callbacks_.end())
     return;
 
   ProxiesResolvedFn callback = it->second;
   pending_callbacks_.erase(it);
-  callback.Run(proxies);
+  callback.Run(std::deque<std::string>(proxies.begin(), proxies.end()));
 }
 
-} // namespace chromeos_update_engine
+}  // namespace chromeos_update_engine
diff --git a/chrome_browser_proxy_resolver.h b/chrome_browser_proxy_resolver.h
index 03dbdad..fcf85b6 100644
--- a/chrome_browser_proxy_resolver.h
+++ b/chrome_browser_proxy_resolver.h
@@ -20,46 +20,29 @@
 #include <deque>
 #include <map>
 #include <string>
+#include <vector>
 
 #include <base/memory/weak_ptr.h>
 
 #include "update_engine/proxy_resolver.h"
 
-namespace brillo {
-class Error;
-}  // namespace brillo
-
-namespace org {
-namespace chromium {
-class NetworkProxyServiceInterfaceProxyInterface;
-}  // namespace chromium
-}  // namespace org
-
 namespace chromeos_update_engine {
 
 class ChromeBrowserProxyResolver : public ProxyResolver {
  public:
-  explicit ChromeBrowserProxyResolver(
-      org::chromium::NetworkProxyServiceInterfaceProxyInterface* dbus_proxy);
+  ChromeBrowserProxyResolver();
   ~ChromeBrowserProxyResolver() override;
 
-  // Parses a string-encoded list of proxies and returns a deque
-  // of individual proxies. The last one will always be kNoProxy.
-  static std::deque<std::string> ParseProxyString(const std::string& input);
-
   // ProxyResolver:
   ProxyRequestId GetProxiesForUrl(const std::string& url,
                                   const ProxiesResolvedFn& callback) override;
   bool CancelProxyRequest(ProxyRequestId request) override;
 
-private:
-  // Callback for successful D-Bus calls made by GetProxiesForUrl().
-  void OnResolveProxyResponse(ProxyRequestId request_id,
-                              const std::string& proxy_info,
-                              const std::string& error_message);
-
-  // Callback for failed D-Bus calls made by GetProxiesForUrl().
-  void OnResolveProxyError(ProxyRequestId request_id, brillo::Error* error);
+ private:
+  // Callback for calls made by GetProxiesForUrl().
+  void OnGetChromeProxyServers(ProxyRequestId request_id,
+                               bool success,
+                               const std::vector<std::string>& proxies);
 
   // Finds the callback identified by |request_id| in |pending_callbacks_|,
   // passes |proxies| to it, and deletes it. Does nothing if the request has
@@ -67,9 +50,6 @@
   void RunCallback(ProxyRequestId request_id,
                    const std::deque<std::string>& proxies);
 
-  // D-Bus proxy for resolving network proxies.
-  org::chromium::NetworkProxyServiceInterfaceProxyInterface* dbus_proxy_;
-
   // Next ID to return from GetProxiesForUrl().
   ProxyRequestId next_request_id_;
 
diff --git a/chrome_browser_proxy_resolver_unittest.cc b/chrome_browser_proxy_resolver_unittest.cc
deleted file mode 100644
index dc71d2b..0000000
--- a/chrome_browser_proxy_resolver_unittest.cc
+++ /dev/null
@@ -1,180 +0,0 @@
-//
-// Copyright (C) 2011 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-
-#include "update_engine/chrome_browser_proxy_resolver.h"
-
-#include <deque>
-#include <string>
-#include <vector>
-
-#include <gmock/gmock.h>
-#include <gtest/gtest.h>
-
-#include <base/macros.h>
-#include <brillo/errors/error.h>
-
-#include "network_proxy/dbus-proxies.h"
-#include "network_proxy/dbus-proxy-mocks.h"
-#include "update_engine/dbus_test_utils.h"
-
-using ::testing::DoAll;
-using ::testing::SaveArg;
-using ::testing::StrEq;
-using ::testing::_;
-using org::chromium::NetworkProxyServiceInterfaceProxyMock;
-using std::deque;
-using std::string;
-using std::vector;
-
-namespace chromeos_update_engine {
-
-namespace {
-
-// Callback for ProxyResolver::GetProxiesForUrl() that copies |src| to |dest|.
-void CopyProxies(deque<string>* dest, const deque<string>& src) {
-  *dest = src;
-}
-
-}  // namespace
-
-class ChromeBrowserProxyResolverTest : public ::testing::Test {
- public:
-  ChromeBrowserProxyResolverTest() = default;
-  ~ChromeBrowserProxyResolverTest() override = default;
-
- protected:
-  // Adds a GoogleMock expectation for a call to |dbus_proxy_|'s
-  // ResolveProxyAsync method to resolve |url|.
-  void AddResolveProxyExpectation(const std::string& url) {
-    EXPECT_CALL(dbus_proxy_, ResolveProxyAsync(StrEq(url), _, _, _))
-        .WillOnce(DoAll(SaveArg<1>(&success_callback_),
-                        SaveArg<2>(&error_callback_)));
-  }
-
-  NetworkProxyServiceInterfaceProxyMock dbus_proxy_;
-  ChromeBrowserProxyResolver resolver_{&dbus_proxy_};
-
-  // Callbacks that were passed to |dbus_proxy_|'s ResolveProxyAsync method.
-  base::Callback<void(const std::string&, const std::string&)>
-      success_callback_;
-  base::Callback<void(brillo::Error*)> error_callback_;
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(ChromeBrowserProxyResolverTest);
-};
-
-TEST_F(ChromeBrowserProxyResolverTest, Parse) {
-  // Test ideas from
-  // http://src.chromium.org/svn/trunk/src/net/proxy/proxy_list_unittest.cc
-  vector<string> inputs = {
-      "PROXY foopy:10",
-      " DIRECT", // leading space.
-      "PROXY foopy1 ; proxy foopy2;\t DIRECT",
-      "proxy foopy1 ; SOCKS foopy2",
-      "DIRECT ; proxy foopy1 ; DIRECT ; SOCKS5 foopy2;DIRECT ",
-      "DIRECT ; proxy foopy1:80; DIRECT ; DIRECT",
-      "PROXY-foopy:10",
-      "PROXY",
-      "PROXY foopy1 ; JUNK ; JUNK ; SOCKS5 foopy2 ; ;",
-      "HTTP foopy1; SOCKS5 foopy2",
-  };
-  vector<deque<string>> outputs = {
-      {"http://foopy:10", kNoProxy},
-      {kNoProxy},
-      {"http://foopy1", "http://foopy2", kNoProxy},
-      {"http://foopy1", "socks4://foopy2", kNoProxy},
-      {kNoProxy, "http://foopy1", kNoProxy, "socks5://foopy2", kNoProxy},
-      {kNoProxy, "http://foopy1:80", kNoProxy, kNoProxy},
-      {kNoProxy},
-      {kNoProxy},
-      {"http://foopy1", "socks5://foopy2", kNoProxy},
-      {"socks5://foopy2", kNoProxy},
-  };
-  ASSERT_EQ(inputs.size(), outputs.size());
-
-  for (size_t i = 0; i < inputs.size(); i++) {
-    deque<string> results =
-        ChromeBrowserProxyResolver::ParseProxyString(inputs[i]);
-    deque<string>& expected = outputs[i];
-    EXPECT_EQ(results.size(), expected.size()) << "i = " << i;
-    if (expected.size() != results.size())
-      continue;
-    for (size_t j = 0; j < expected.size(); j++) {
-      EXPECT_EQ(expected[j], results[j]) << "i = " << i;
-    }
-  }
-}
-
-TEST_F(ChromeBrowserProxyResolverTest, Success) {
-  const char kUrl[] = "http://example.com/blah";
-  const char kProxyConfig[] = "SOCKS5 192.168.52.83:5555;DIRECT";
-  AddResolveProxyExpectation(kUrl);
-  deque<string> proxies;
-  resolver_.GetProxiesForUrl(kUrl, base::Bind(&CopyProxies, &proxies));
-
-  // Run the D-Bus success callback and verify that the proxies are passed to
-  // the supplied function.
-  ASSERT_FALSE(success_callback_.is_null());
-  success_callback_.Run(kProxyConfig, string());
-  ASSERT_EQ(2u, proxies.size());
-  EXPECT_EQ("socks5://192.168.52.83:5555", proxies[0]);
-  EXPECT_EQ(kNoProxy, proxies[1]);
-}
-
-TEST_F(ChromeBrowserProxyResolverTest, Failure) {
-  const char kUrl[] = "http://example.com/blah";
-  AddResolveProxyExpectation(kUrl);
-  deque<string> proxies;
-  resolver_.GetProxiesForUrl(kUrl, base::Bind(&CopyProxies, &proxies));
-
-  // Run the D-Bus error callback and verify that the supplied function is
-  // instructed to use a direct connection.
-  ASSERT_FALSE(error_callback_.is_null());
-  brillo::ErrorPtr error = brillo::Error::Create(FROM_HERE, "", "", "");
-  error_callback_.Run(error.get());
-  ASSERT_EQ(1u, proxies.size());
-  EXPECT_EQ(kNoProxy, proxies[0]);
-}
-
-TEST_F(ChromeBrowserProxyResolverTest, CancelCallback) {
-  const char kUrl[] = "http://example.com/blah";
-  AddResolveProxyExpectation(kUrl);
-  int called = 0;
-  auto callback = base::Bind(
-      [](int* called, const deque<string>& proxies) { (*called)++; }, &called);
-  ProxyRequestId request = resolver_.GetProxiesForUrl(kUrl, callback);
-
-  // Cancel the request and then run the D-Bus success callback. The original
-  // callback shouldn't be run.
-  EXPECT_TRUE(resolver_.CancelProxyRequest(request));
-  ASSERT_FALSE(success_callback_.is_null());
-  success_callback_.Run("DIRECT", string());
-  EXPECT_EQ(0, called);
-}
-
-TEST_F(ChromeBrowserProxyResolverTest, CancelCallbackTwice) {
-  const char kUrl[] = "http://example.com/blah";
-  AddResolveProxyExpectation(kUrl);
-  deque<string> proxies;
-  ProxyRequestId request =
-      resolver_.GetProxiesForUrl(kUrl, base::Bind(&CopyProxies, &proxies));
-
-  // Cancel the same request twice. The second call should fail.
-  EXPECT_TRUE(resolver_.CancelProxyRequest(request));
-  EXPECT_FALSE(resolver_.CancelProxyRequest(request));
-}
-
-}  // namespace chromeos_update_engine
diff --git a/client_library/client_binder.cc b/client_library/client_binder.cc
index e98c225..54b33ed 100644
--- a/client_library/client_binder.cc
+++ b/client_library/client_binder.cc
@@ -25,15 +25,15 @@
 #include "update_engine/parcelable_update_engine_status.h"
 #include "update_engine/update_status_utils.h"
 
-using android::OK;
-using android::String16;
-using android::String8;
 using android::binder::Status;
 using android::brillo::ParcelableUpdateEngineStatus;
 using android::getService;
+using android::OK;
+using android::String16;
+using android::String8;
 using chromeos_update_engine::StringToUpdateStatus;
-using chromeos_update_engine::UpdateEngineService;
 using std::string;
+using update_engine::UpdateAttemptFlags;
 
 namespace update_engine {
 namespace internal {
@@ -48,10 +48,14 @@
 bool BinderUpdateEngineClient::AttemptUpdate(const string& in_app_version,
                                              const string& in_omaha_url,
                                              bool at_user_request) {
-  return service_->AttemptUpdate(String16{in_app_version.c_str()},
-      String16{in_omaha_url.c_str()},
-      at_user_request ? 0 :
-          UpdateEngineService::kAttemptUpdateFlagNonInteractive).isOk();
+  bool started;
+  return service_
+      ->AttemptUpdate(
+          String16{in_app_version.c_str()},
+          String16{in_omaha_url.c_str()},
+          at_user_request ? 0 : UpdateAttemptFlags::kFlagNonInteractive,
+          &started)
+      .isOk();
 }
 
 bool BinderUpdateEngineClient::GetStatus(int64_t* out_last_checked_time,
@@ -143,18 +147,18 @@
 }
 
 Status BinderUpdateEngineClient::StatusUpdateCallback::HandleStatusUpdate(
-    int64_t last_checked_time,
-    double progress,
-    const String16& current_operation,
-    const String16& new_version,
-    int64_t new_size) {
+    const ParcelableUpdateEngineStatus& status) {
   UpdateStatus update_status;
 
-  StringToUpdateStatus(String8{current_operation}.string(), &update_status);
+  StringToUpdateStatus(String8{status.current_operation_}.string(),
+                       &update_status);
 
   for (auto& handler : client_->handlers_) {
-    handler->HandleStatusUpdate(last_checked_time, progress, update_status,
-                                String8{new_version}.string(), new_size);
+    handler->HandleStatusUpdate(status.last_checked_time_,
+                                status.progress_,
+                                update_status,
+                                String8{status.new_version_}.string(),
+                                status.new_size_);
   }
 
   return Status::ok();
diff --git a/client_library/client_binder.h b/client_library/client_binder.h
index b1b34da..17f2beb 100644
--- a/client_library/client_binder.h
+++ b/client_library/client_binder.h
@@ -94,11 +94,7 @@
         : client_(client) {}
 
     android::binder::Status HandleStatusUpdate(
-        int64_t last_checked_time,
-        double progress,
-        const android::String16& current_operation,
-        const android::String16& new_version,
-        int64_t new_size) override;
+        const android::brillo::ParcelableUpdateEngineStatus& status) override;
 
    private:
     BinderUpdateEngineClient* client_;
diff --git a/client_library/include/update_engine/update_status.h b/client_library/include/update_engine/update_status.h
index 3e9af5b..41fab48 100644
--- a/client_library/include/update_engine/update_status.h
+++ b/client_library/include/update_engine/update_status.h
@@ -17,6 +17,10 @@
 #ifndef UPDATE_ENGINE_CLIENT_LIBRARY_INCLUDE_UPDATE_ENGINE_UPDATE_STATUS_H_
 #define UPDATE_ENGINE_CLIENT_LIBRARY_INCLUDE_UPDATE_ENGINE_UPDATE_STATUS_H_
 
+#include <string>
+
+#include <brillo/enum_flags.h>
+
 namespace update_engine {
 
 enum class UpdateStatus {
@@ -32,6 +36,39 @@
   DISABLED,
 };
 
+// Enum of bit-wise flags for controlling how updates are attempted.
+enum UpdateAttemptFlags : int32_t {
+  kNone = 0,
+  // Treat the update like a non-interactive update, even when being triggered
+  // by the interactive APIs.
+  kFlagNonInteractive = (1 << 0),
+  // Restrict (disallow) downloading of updates.
+  kFlagRestrictDownload = (1 << 1),
+};
+
+// Enable bit-wise operators for the above enumeration of flag values.
+DECLARE_FLAGS_ENUM(UpdateAttemptFlags);
+
+struct UpdateEngineStatus {
+  // When the update_engine last checked for updates (time_t: seconds from unix
+  // epoch)
+  int64_t last_checked_time;
+  // the current status/operation of the update_engine
+  UpdateStatus status;
+  // the current product version (oem bundle id)
+  std::string current_version;
+  // the current system version
+  std::string current_system_version;
+  // The current progress (0.0f-1.0f).
+  double progress;
+  // the size of the update (bytes)
+  uint64_t new_size_bytes;
+  // the new product version
+  std::string new_version;
+  // the new system version, if there is one (empty, otherwise)
+  std::string new_system_version;
+};
+
 }  // namespace update_engine
 
 #endif  // UPDATE_ENGINE_CLIENT_LIBRARY_INCLUDE_UPDATE_ENGINE_UPDATE_STATUS_H_
diff --git a/common/constants.cc b/common/constants.cc
index c0a6e27..5941c93 100644
--- a/common/constants.cc
+++ b/common/constants.cc
@@ -57,6 +57,7 @@
 const char kPrefsP2PFirstAttemptTimestamp[] = "p2p-first-attempt-timestamp";
 const char kPrefsP2PNumAttempts[] = "p2p-num-attempts";
 const char kPrefsPayloadAttemptNumber[] = "payload-attempt-number";
+const char kPrefsPostInstallSucceeded[] = "post-install-succeeded";
 const char kPrefsPreviousVersion[] = "previous-version";
 const char kPrefsResumedUpdateFailures[] = "resumed-update-failures";
 const char kPrefsRollbackVersion[] = "rollback-version";
@@ -103,5 +104,12 @@
 // This can be used to zero-rate OTA traffic by sending it over the correct
 // network.
 const char kPayloadPropertyNetworkId[] = "NETWORK_ID";
+// Set "SWITCH_SLOT_ON_REBOOT=0" to skip marking the updated partitions active.
+// The default is 1 (always switch slot if update succeeded).
+const char kPayloadPropertySwitchSlotOnReboot[] = "SWITCH_SLOT_ON_REBOOT";
+// Set "RUN_POST_INSTALL=0" to skip running post install, this will only be
+// honored if we're resuming an update and post install has already succeeded.
+// The default is 1 (always run post install).
+const char kPayloadPropertyRunPostInstall[] = "RUN_POST_INSTALL";
 
 }  // namespace chromeos_update_engine
diff --git a/common/constants.h b/common/constants.h
index 776e726..26773cf 100644
--- a/common/constants.h
+++ b/common/constants.h
@@ -59,6 +59,7 @@
 extern const char kPrefsP2PFirstAttemptTimestamp[];
 extern const char kPrefsP2PNumAttempts[];
 extern const char kPrefsPayloadAttemptNumber[];
+extern const char kPrefsPostInstallSucceeded[];
 extern const char kPrefsPreviousVersion[];
 extern const char kPrefsResumedUpdateFailures[];
 extern const char kPrefsRollbackVersion[];
@@ -96,6 +97,8 @@
 extern const char kPayloadPropertyUserAgent[];
 extern const char kPayloadPropertyPowerwash[];
 extern const char kPayloadPropertyNetworkId[];
+extern const char kPayloadPropertySwitchSlotOnReboot[];
+extern const char kPayloadPropertyRunPostInstall[];
 
 // A download source is any combination of protocol and server (that's of
 // interest to us when looking at UMA metrics) using which we may download
@@ -173,6 +176,7 @@
 // succeeding. When using p2p, this is low in order to fail fast.
 const int kDownloadMaxRetryCount = 20;
 const int kDownloadMaxRetryCountOobeNotComplete = 3;
+const int kDownloadMaxRetryCountInteractive = 3;
 const int kDownloadP2PMaxRetryCount = 5;
 
 // The connect timeout, in seconds.
diff --git a/common/error_code.h b/common/error_code.h
index 3800bf0..0b08005 100644
--- a/common/error_code.h
+++ b/common/error_code.h
@@ -75,6 +75,7 @@
   kNonCriticalUpdateInOOBE = 49,
   // kOmahaUpdateIgnoredOverCellular = 50,
   kPayloadTimestampError = 51,
+  kUpdatedButNotActive = 52,
 
   // VERY IMPORTANT! When adding new error codes:
   //
diff --git a/common/error_code_utils.cc b/common/error_code_utils.cc
index 0a015eb..313a15f 100644
--- a/common/error_code_utils.cc
+++ b/common/error_code_utils.cc
@@ -146,8 +146,10 @@
       return "ErrorCode::kNonCriticalUpdateInOOBE";
     case ErrorCode::kPayloadTimestampError:
       return "ErrorCode::kPayloadTimestampError";
-    // Don't add a default case to let the compiler warn about newly added
-    // error codes which should be added here.
+    case ErrorCode::kUpdatedButNotActive:
+      return "ErrorCode::kUpdatedButNotActive";
+      // Don't add a default case to let the compiler warn about newly added
+      // error codes which should be added here.
   }
 
   return "Unknown error: " + base::UintToString(static_cast<unsigned>(code));
diff --git a/common/fake_hardware.h b/common/fake_hardware.h
index a384597..f2b2c9d 100644
--- a/common/fake_hardware.h
+++ b/common/fake_hardware.h
@@ -83,6 +83,14 @@
 
   int64_t GetBuildTimestamp() const override { return build_timestamp_; }
 
+  bool GetFirstActiveOmahaPingSent() const override {
+    return first_active_omaha_ping_sent_;
+  }
+
+  void SetFirstActiveOmahaPingSent() override {
+    first_active_omaha_ping_sent_ = true;
+  }
+
   // Setters
   void SetIsOfficialBuild(bool is_official_build) {
     is_official_build_ = is_official_build;
@@ -144,6 +152,7 @@
   int powerwash_count_{kPowerwashCountNotSet};
   bool powerwash_scheduled_{false};
   int64_t build_timestamp_{0};
+  bool first_active_omaha_ping_sent_{false};
 
   DISALLOW_COPY_AND_ASSIGN(FakeHardware);
 };
diff --git a/common/hardware_interface.h b/common/hardware_interface.h
index c9e2f85..94442d1 100644
--- a/common/hardware_interface.h
+++ b/common/hardware_interface.h
@@ -94,6 +94,15 @@
 
   // Returns the timestamp of the current OS build.
   virtual int64_t GetBuildTimestamp() const = 0;
+
+  // Returns whether the first active ping was sent to Omaha at some point, and
+  // that the value is persisted across recovery (and powerwash) once set with
+  // |SetFirstActiveOmahaPingSent()|.
+  virtual bool GetFirstActiveOmahaPingSent() const = 0;
+
+  // Persist the fact that first active ping was sent to omaha. It bails out if
+  // it fails.
+  virtual void SetFirstActiveOmahaPingSent() = 0;
 };
 
 }  // namespace chromeos_update_engine
diff --git a/common/http_fetcher_unittest.cc b/common/http_fetcher_unittest.cc
index dcc1573..867216e 100644
--- a/common/http_fetcher_unittest.cc
+++ b/common/http_fetcher_unittest.cc
@@ -32,7 +32,6 @@
 #include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
 #include <base/time/time.h>
-#include <brillo/bind_lambda.h>
 #include <brillo/message_loops/base_message_loop.h>
 #include <brillo/message_loops/message_loop.h>
 #include <brillo/message_loops/message_loop_utils.h>
@@ -634,7 +633,7 @@
   fetcher->Unpause();
   fetcher->Pause();
   // Proxy resolver comes back after we paused the fetcher.
-  ASSERT_TRUE(proxy_callback);
+  ASSERT_FALSE(proxy_callback.is_null());
   proxy_callback.Run({1, kNoProxy});
 }
 
diff --git a/common/hwid_override_unittest.cc b/common/hwid_override_unittest.cc
index 26ef30a..35e6438 100644
--- a/common/hwid_override_unittest.cc
+++ b/common/hwid_override_unittest.cc
@@ -32,7 +32,7 @@
 
   void SetUp() override {
     ASSERT_TRUE(tempdir_.CreateUniqueTempDir());
-    ASSERT_TRUE(base::CreateDirectory(tempdir_.path().Append("etc")));
+    ASSERT_TRUE(base::CreateDirectory(tempdir_.GetPath().Append("etc")));
   }
 
  protected:
@@ -46,22 +46,24 @@
   std::string expected_hwid("expected");
   std::string keyval(HwidOverride::kHwidOverrideKey);
   keyval += ("=" + expected_hwid);
-  ASSERT_EQ(base::WriteFile(tempdir_.path().Append("etc/lsb-release"),
-                            keyval.c_str(), keyval.length()),
+  ASSERT_EQ(base::WriteFile(tempdir_.GetPath().Append("etc/lsb-release"),
+                            keyval.c_str(),
+                            keyval.length()),
             static_cast<int>(keyval.length()));
-  EXPECT_EQ(expected_hwid, HwidOverride::Read(tempdir_.path()));
+  EXPECT_EQ(expected_hwid, HwidOverride::Read(tempdir_.GetPath()));
 }
 
 TEST_F(HwidOverrideTest, ReadNothing) {
   std::string keyval("SOMETHING_ELSE=UNINTERESTING");
-  ASSERT_EQ(base::WriteFile(tempdir_.path().Append("etc/lsb-release"),
-                            keyval.c_str(), keyval.length()),
+  ASSERT_EQ(base::WriteFile(tempdir_.GetPath().Append("etc/lsb-release"),
+                            keyval.c_str(),
+                            keyval.length()),
             static_cast<int>(keyval.length()));
-  EXPECT_EQ(std::string(), HwidOverride::Read(tempdir_.path()));
+  EXPECT_EQ(std::string(), HwidOverride::Read(tempdir_.GetPath()));
 }
 
 TEST_F(HwidOverrideTest, ReadFailure) {
-  EXPECT_EQ(std::string(), HwidOverride::Read(tempdir_.path()));
+  EXPECT_EQ(std::string(), HwidOverride::Read(tempdir_.GetPath()));
 }
 
 }  // namespace chromeos_update_engine
diff --git a/common/mock_hardware.h b/common/mock_hardware.h
index 1c4253a..42fa7ba 100644
--- a/common/mock_hardware.h
+++ b/common/mock_hardware.h
@@ -63,6 +63,12 @@
     ON_CALL(*this, GetPowerwashSafeDirectory(testing::_))
       .WillByDefault(testing::Invoke(&fake_,
             &FakeHardware::GetPowerwashSafeDirectory));
+    ON_CALL(*this, GetFirstActiveOmahaPingSent())
+      .WillByDefault(testing::Invoke(&fake_,
+            &FakeHardware::GetFirstActiveOmahaPingSent()));
+    ON_CALL(*this, SetFirstActiveOmahaPingSent())
+      .WillByDefault(testing::Invoke(&fake_,
+            &FakeHardware::SetFirstActiveOmahaPingSent()));
   }
 
   ~MockHardware() override = default;
@@ -78,6 +84,7 @@
   MOCK_CONST_METHOD0(GetPowerwashCount, int());
   MOCK_CONST_METHOD1(GetNonVolatileDirectory, bool(base::FilePath*));
   MOCK_CONST_METHOD1(GetPowerwashSafeDirectory, bool(base::FilePath*));
+  MOCK_CONST_METHOD0(GetFirstActiveOmahaPingSent, bool());
 
   // Returns a reference to the underlying FakeHardware.
   FakeHardware& fake() {
diff --git a/common/prefs_unittest.cc b/common/prefs_unittest.cc
index 73ceb00..aa2eb04 100644
--- a/common/prefs_unittest.cc
+++ b/common/prefs_unittest.cc
@@ -44,7 +44,7 @@
  protected:
   void SetUp() override {
     ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
-    prefs_dir_ = temp_dir_.path();
+    prefs_dir_ = temp_dir_.GetPath();
     ASSERT_TRUE(prefs_.Init(prefs_dir_));
   }
 
diff --git a/common/subprocess_unittest.cc b/common/subprocess_unittest.cc
index cbc9a85..c8996db 100644
--- a/common/subprocess_unittest.cc
+++ b/common/subprocess_unittest.cc
@@ -32,7 +32,6 @@
 #include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
 #include <base/time/time.h>
-#include <brillo/bind_lambda.h>
 #include <brillo/message_loops/base_message_loop.h>
 #include <brillo/message_loops/message_loop.h>
 #include <brillo/message_loops/message_loop_utils.h>
@@ -225,7 +224,7 @@
 TEST_F(SubprocessTest, CancelTest) {
   base::ScopedTempDir tempdir;
   ASSERT_TRUE(tempdir.CreateUniqueTempDir());
-  string fifo_path = tempdir.path().Append("fifo").value();
+  string fifo_path = tempdir.GetPath().Append("fifo").value();
   EXPECT_EQ(0, mkfifo(fifo_path.c_str(), 0666));
 
   // Start a process, make sure it is running and try to cancel it. We write
diff --git a/common/test_utils.cc b/common/test_utils.cc
index fb22c80..85f78f9 100644
--- a/common/test_utils.cc
+++ b/common/test_utils.cc
@@ -24,6 +24,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/ioctl.h>
+#include <sys/mount.h>
 #include <sys/stat.h>
 #include <sys/sysmacros.h>
 #include <sys/types.h>
@@ -201,6 +202,13 @@
   device_info.lo_file_name[LO_NAME_SIZE - 1] = '\0';
   TEST_AND_RETURN_FALSE_ERRNO(
       ioctl(loop_device_fd, LOOP_SET_STATUS64, &device_info) == 0);
+  if (writable) {
+    // Make sure loop device isn't read only.
+    int ro = 0;
+    if (ioctl(loop_device_fd, BLKROSET, &ro) != 0) {
+      PLOG(WARNING) << "Failed to mark loop device writable.";
+    }
+  }
   return true;
 }
 
@@ -248,7 +256,7 @@
                                      string* mnt_path,
                                      unsigned long flags) {  // NOLINT - long
   EXPECT_TRUE(temp_dir_.CreateUniqueTempDir());
-  *mnt_path = temp_dir_.path().value();
+  *mnt_path = temp_dir_.GetPath().value();
 
   string loop_dev;
   loop_binder_.reset(
diff --git a/common/test_utils.h b/common/test_utils.h
index ba9f5f2..ddb3d34 100644
--- a/common/test_utils.h
+++ b/common/test_utils.h
@@ -31,6 +31,7 @@
 #include <base/callback.h>
 #include <base/files/file_path.h>
 #include <base/files/scoped_temp_dir.h>
+#include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
 #include "update_engine/common/action.h"
@@ -101,6 +102,11 @@
 
 void FillWithData(brillo::Blob* buffer);
 
+// Compare the value of native array for download source parameter.
+MATCHER_P(DownloadSourceMatcher, source_array, "") {
+  return std::equal(source_array, source_array + kNumDownloadSources, arg);
+}
+
 // Class to unmount FS when object goes out of scope
 class ScopedFilesystemUnmounter {
  public:
diff --git a/common/utils.cc b/common/utils.cc
index f528660..f651823 100644
--- a/common/utils.cc
+++ b/common/utils.cc
@@ -57,7 +57,6 @@
 #include "update_engine/common/prefs_interface.h"
 #include "update_engine/common/subprocess.h"
 #include "update_engine/payload_consumer/file_descriptor.h"
-#include "update_engine/payload_consumer/payload_constants.h"
 
 using base::Time;
 using base::TimeDelta;
@@ -1035,19 +1034,6 @@
   return false;
 }
 
-bool IsZlibCompatible(const string& fingerprint) {
-  if (fingerprint.size() != sizeof(kCompatibleZlibFingerprint[0]) - 1) {
-    LOG(ERROR) << "Invalid fingerprint: " << fingerprint;
-    return false;
-  }
-  for (auto& f : kCompatibleZlibFingerprint) {
-    if (base::CompareCaseInsensitiveASCII(fingerprint, f) == 0) {
-      return true;
-    }
-  }
-  return false;
-}
-
 bool ReadExtents(const string& path, const vector<Extent>& extents,
                  brillo::Blob* out_data, ssize_t out_data_size,
                  size_t block_size) {
diff --git a/common/utils.h b/common/utils.h
index eaf2640..e4ffcf8 100644
--- a/common/utils.h
+++ b/common/utils.h
@@ -88,8 +88,8 @@
 bool PReadAll(int fd, void* buf, size_t count, off_t offset,
               ssize_t* out_bytes_read);
 
-bool PReadAll(const FileDescriptorPtr& fd, void* buf, size_t count, off_t offset,
-              ssize_t* out_bytes_read);
+bool PReadAll(const FileDescriptorPtr& fd, void* buf, size_t count,
+              off_t offset, ssize_t* out_bytes_read);
 
 // Opens |path| for reading and appends its entire content to the container
 // pointed to by |out_p|. Returns true upon successfully reading all of the
@@ -256,6 +256,16 @@
   }
 }
 
+// Return the total number of blocks in the passed |extents| collection.
+template <class T>
+uint64_t BlocksInExtents(const T& extents) {
+  uint64_t sum = 0;
+  for (const auto& ext : extents) {
+    sum += ext.num_blocks();
+  }
+  return sum;
+}
+
 // Converts seconds into human readable notation including days, hours, minutes
 // and seconds. For example, 185 will yield 3m5s, 4300 will yield 1h11m40s, and
 // 360000 will yield 4d4h0m0s.  Zero padding not applied. Seconds are always
@@ -308,9 +318,6 @@
 bool GetMinorVersion(const brillo::KeyValueStore& store,
                      uint32_t* minor_version);
 
-// Returns whether zlib |fingerprint| is compatible with zlib we are using.
-bool IsZlibCompatible(const std::string& fingerprint);
-
 // This function reads the specified data in |extents| into |out_data|. The
 // extents are read from the file at |path|. |out_data_size| is the size of
 // |out_data|. Returns false if the number of bytes to read given in
diff --git a/common/utils_unittest.cc b/common/utils_unittest.cc
index 6e9a911..62f9f6c 100644
--- a/common/utils_unittest.cc
+++ b/common/utils_unittest.cc
@@ -100,11 +100,11 @@
 TEST(UtilsTest, IsSymlinkTest) {
   base::ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
-  string temp_file = temp_dir.path().Append("temp-file").value();
+  string temp_file = temp_dir.GetPath().Append("temp-file").value();
   EXPECT_TRUE(utils::WriteFile(temp_file.c_str(), "", 0));
-  string temp_symlink = temp_dir.path().Append("temp-symlink").value();
+  string temp_symlink = temp_dir.GetPath().Append("temp-symlink").value();
   EXPECT_EQ(0, symlink(temp_file.c_str(), temp_symlink.c_str()));
-  EXPECT_FALSE(utils::IsSymlink(temp_dir.path().value().c_str()));
+  EXPECT_FALSE(utils::IsSymlink(temp_dir.GetPath().value().c_str()));
   EXPECT_FALSE(utils::IsSymlink(temp_file.c_str()));
   EXPECT_TRUE(utils::IsSymlink(temp_symlink.c_str()));
   EXPECT_FALSE(utils::IsSymlink("/non/existent/path"));
@@ -303,8 +303,9 @@
   base::Time::Exploded exploded = (base::Time::Exploded) {
     .year = 2001, .month = 9, .day_of_week = 0, .day_of_month = 9,
     .hour = 1, .minute = 46, .second = 40, .millisecond = 42};
-  EXPECT_EQ(base::Time::FromUTCExploded(exploded),
-            utils::TimeFromStructTimespec(&ts));
+  base::Time time;
+  EXPECT_TRUE(base::Time::FromUTCExploded(exploded, &time));
+  EXPECT_EQ(time, utils::TimeFromStructTimespec(&ts));
 }
 
 TEST(UtilsTest, DecodeAndStoreBase64String) {
@@ -478,23 +479,23 @@
   test_utils::ScopedLoopbackDeviceBinder loop_binder(
       tmp_image, true, &loop_dev);
 
-  EXPECT_FALSE(utils::IsMountpoint(mnt_dir.path().value()));
+  EXPECT_FALSE(utils::IsMountpoint(mnt_dir.GetPath().value()));
   // This is the actual test part. While we hold a file descriptor open for the
   // mounted filesystem, umount should still succeed.
   EXPECT_TRUE(utils::MountFilesystem(
-      loop_dev, mnt_dir.path().value(), MS_RDONLY, "ext4", ""));
+      loop_dev, mnt_dir.GetPath().value(), MS_RDONLY, "ext4", ""));
   // Verify the directory is a mount point now.
-  EXPECT_TRUE(utils::IsMountpoint(mnt_dir.path().value()));
+  EXPECT_TRUE(utils::IsMountpoint(mnt_dir.GetPath().value()));
 
-  string target_file = mnt_dir.path().Append("empty-file").value();
+  string target_file = mnt_dir.GetPath().Append("empty-file").value();
   int fd = HANDLE_EINTR(open(target_file.c_str(), O_RDONLY));
   EXPECT_GE(fd, 0);
-  EXPECT_TRUE(utils::UnmountFilesystem(mnt_dir.path().value()));
+  EXPECT_TRUE(utils::UnmountFilesystem(mnt_dir.GetPath().value()));
   // The filesystem should be already unmounted at this point.
-  EXPECT_FALSE(utils::IsMountpoint(mnt_dir.path().value()));
+  EXPECT_FALSE(utils::IsMountpoint(mnt_dir.GetPath().value()));
   IGNORE_EINTR(close(fd));
   // The filesystem was already unmounted so this call should fail.
-  EXPECT_FALSE(utils::UnmountFilesystem(mnt_dir.path().value()));
+  EXPECT_FALSE(utils::UnmountFilesystem(mnt_dir.GetPath().value()));
 }
 
 TEST(UtilsTest, IsMountpointTest) {
@@ -503,7 +504,7 @@
 
   base::ScopedTempDir mnt_dir;
   EXPECT_TRUE(mnt_dir.CreateUniqueTempDir());
-  EXPECT_FALSE(utils::IsMountpoint(mnt_dir.path().value()));
+  EXPECT_FALSE(utils::IsMountpoint(mnt_dir.GetPath().value()));
 
   base::FilePath file;
   EXPECT_TRUE(base::CreateTemporaryFile(&file));
diff --git a/common_service.cc b/common_service.cc
index 1a41b63..9f3b862 100644
--- a/common_service.cc
+++ b/common_service.cc
@@ -19,10 +19,10 @@
 #include <set>
 #include <string>
 
+#include <base/bind.h>
 #include <base/location.h>
 #include <base/logging.h>
 #include <base/strings/stringprintf.h>
-#include <brillo/bind_lambda.h>
 #include <brillo/message_loops/message_loop.h>
 #include <brillo/strings/string_utils.h>
 #include <policy/device_policy.h>
@@ -43,6 +43,8 @@
 using brillo::string_utils::ToString;
 using std::set;
 using std::string;
+using update_engine::UpdateAttemptFlags;
+using update_engine::UpdateEngineStatus;
 
 namespace chromeos_update_engine {
 
@@ -71,19 +73,35 @@
 
 // org::chromium::UpdateEngineInterfaceInterface methods implementation.
 
+bool UpdateEngineService::SetUpdateAttemptFlags(ErrorPtr* /* error */,
+                                                int32_t in_flags_as_int) {
+  auto flags = static_cast<UpdateAttemptFlags>(in_flags_as_int);
+  LOG(INFO) << "Setting Update Attempt Flags: "
+            << "flags=0x" << std::hex << flags << " "
+            << "RestrictDownload="
+            << ((flags & UpdateAttemptFlags::kFlagRestrictDownload) ? "yes"
+                                                                    : "no");
+  system_state_->update_attempter()->SetUpdateAttemptFlags(flags);
+  return true;
+}
+
 bool UpdateEngineService::AttemptUpdate(ErrorPtr* /* error */,
                                         const string& in_app_version,
                                         const string& in_omaha_url,
-                                        int32_t in_flags_as_int) {
-  AttemptUpdateFlags flags = static_cast<AttemptUpdateFlags>(in_flags_as_int);
-  bool interactive = !(flags & kAttemptUpdateFlagNonInteractive);
+                                        int32_t in_flags_as_int,
+                                        bool* out_result) {
+  auto flags = static_cast<UpdateAttemptFlags>(in_flags_as_int);
+  bool interactive = !(flags & UpdateAttemptFlags::kFlagNonInteractive);
+  bool restrict_downloads = (flags & UpdateAttemptFlags::kFlagRestrictDownload);
 
   LOG(INFO) << "Attempt update: app_version=\"" << in_app_version << "\" "
             << "omaha_url=\"" << in_omaha_url << "\" "
             << "flags=0x" << std::hex << flags << " "
-            << "interactive=" << (interactive ? "yes" : "no");
-  system_state_->update_attempter()->CheckForUpdate(
-      in_app_version, in_omaha_url, interactive);
+            << "interactive=" << (interactive ? "yes " : "no ")
+            << "RestrictDownload=" << (restrict_downloads ? "yes " : "no ");
+
+  *out_result = system_state_->update_attempter()->CheckForUpdate(
+      in_app_version, in_omaha_url, flags);
   return true;
 }
 
@@ -116,16 +134,8 @@
 }
 
 bool UpdateEngineService::GetStatus(ErrorPtr* error,
-                                    int64_t* out_last_checked_time,
-                                    double* out_progress,
-                                    string* out_current_operation,
-                                    string* out_new_version,
-                                    int64_t* out_new_size) {
-  if (!system_state_->update_attempter()->GetStatus(out_last_checked_time,
-                                                    out_progress,
-                                                    out_current_operation,
-                                                    out_new_version,
-                                                    out_new_size)) {
+                                    UpdateEngineStatus* out_status) {
+  if (!system_state_->update_attempter()->GetStatus(out_status)) {
     LogAndSetError(error, FROM_HERE, "GetStatus failed.");
     return false;
   }
diff --git a/common_service.h b/common_service.h
index 69368fb..544dd93 100644
--- a/common_service.h
+++ b/common_service.h
@@ -24,17 +24,13 @@
 #include <base/memory/ref_counted.h>
 #include <brillo/errors/error.h>
 
+#include "update_engine/client_library/include/update_engine/update_status.h"
 #include "update_engine/system_state.h"
 
 namespace chromeos_update_engine {
 
 class UpdateEngineService {
  public:
-  // Flags used in the AttemptUpdateWithFlags() D-Bus method.
-  typedef enum {
-    kAttemptUpdateFlagNonInteractive = (1<<0)
-  } AttemptUpdateFlags;
-
   // Error domain for all the service errors.
   static const char* const kErrorDomain;
 
@@ -44,10 +40,17 @@
   explicit UpdateEngineService(SystemState* system_state);
   virtual ~UpdateEngineService() = default;
 
+  // Set flags that influence how updates and checks are performed.  These
+  // influence all future checks and updates until changed or the device
+  // reboots.  The |in_flags_as_int| values are a union of values from
+  // |UpdateAttemptFlags|
+  bool SetUpdateAttemptFlags(brillo::ErrorPtr* error, int32_t in_flags_as_int);
+
   bool AttemptUpdate(brillo::ErrorPtr* error,
                      const std::string& in_app_version,
                      const std::string& in_omaha_url,
-                     int32_t in_flags_as_int);
+                     int32_t in_flags_as_int,
+                     bool* out_result);
 
   bool AttemptRollback(brillo::ErrorPtr* error, bool in_powerwash);
 
@@ -63,11 +66,7 @@
   // progress, the number of operations, size to download and overall progress
   // is reported.
   bool GetStatus(brillo::ErrorPtr* error,
-                 int64_t* out_last_checked_time,
-                 double* out_progress,
-                 std::string* out_current_operation,
-                 std::string* out_new_version,
-                 int64_t* out_new_size);
+                 update_engine::UpdateEngineStatus* out_status);
 
   // Reboots the device if an update is applied and a reboot is required.
   bool RebootIfNeeded(brillo::ErrorPtr* error);
diff --git a/common_service_unittest.cc b/common_service_unittest.cc
index 0a7bfc3..d9ef567 100644
--- a/common_service_unittest.cc
+++ b/common_service_unittest.cc
@@ -28,9 +28,10 @@
 #include "update_engine/omaha_utils.h"
 
 using std::string;
-using testing::Return;
-using testing::SetArgumentPointee;
 using testing::_;
+using testing::Return;
+using testing::SetArgPointee;
+using update_engine::UpdateAttemptFlags;
 
 namespace chromeos_update_engine {
 
@@ -56,13 +57,32 @@
 };
 
 TEST_F(UpdateEngineServiceTest, AttemptUpdate) {
-  EXPECT_CALL(*mock_update_attempter_, CheckForUpdate(
-      "app_ver", "url", false /* interactive */));
-  // The update is non-interactive when we pass the non-interactive flag.
-  EXPECT_TRUE(common_service_.AttemptUpdate(
-      &error_, "app_ver", "url",
-      UpdateEngineService::kAttemptUpdateFlagNonInteractive));
+  EXPECT_CALL(
+      *mock_update_attempter_,
+      CheckForUpdate("app_ver", "url", UpdateAttemptFlags::kFlagNonInteractive))
+      .WillOnce(Return(true));
+
+  // The non-interactive flag needs to be passed through to CheckForUpdate.
+  bool result = false;
+  EXPECT_TRUE(
+      common_service_.AttemptUpdate(&error_,
+                                    "app_ver",
+                                    "url",
+                                    UpdateAttemptFlags::kFlagNonInteractive,
+                                    &result));
   EXPECT_EQ(nullptr, error_);
+  EXPECT_TRUE(result);
+}
+
+TEST_F(UpdateEngineServiceTest, AttemptUpdateReturnsFalse) {
+  EXPECT_CALL(*mock_update_attempter_,
+              CheckForUpdate("app_ver", "url", UpdateAttemptFlags::kNone))
+      .WillOnce(Return(false));
+  bool result = true;
+  EXPECT_TRUE(common_service_.AttemptUpdate(
+      &error_, "app_ver", "url", UpdateAttemptFlags::kNone, &result));
+  EXPECT_EQ(nullptr, error_);
+  EXPECT_FALSE(result);
 }
 
 // SetChannel is allowed when there's no device policy (the device is not
@@ -82,7 +102,7 @@
   policy::MockDevicePolicy mock_device_policy;
   fake_system_state_.set_device_policy(&mock_device_policy);
   EXPECT_CALL(mock_device_policy, GetReleaseChannelDelegated(_))
-      .WillOnce(DoAll(SetArgumentPointee<0>(true), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<0>(true), Return(true)));
   EXPECT_CALL(*fake_system_state_.mock_request_params(),
               SetTargetChannel("beta-channel", true, _))
       .WillOnce(Return(true));
diff --git a/connection_manager.cc b/connection_manager.cc
index f72d9e8..d15faf0 100644
--- a/connection_manager.cc
+++ b/connection_manager.cc
@@ -73,7 +73,7 @@
       if (device_policy->GetAllowedConnectionTypesForUpdate(&allowed_types)) {
         // The update setting is enforced by the device policy.
 
-        if (!ContainsKey(allowed_types, shill::kTypeCellular)) {
+        if (!base::ContainsKey(allowed_types, shill::kTypeCellular)) {
           LOG(INFO) << "Disabling updates over cellular connection as it's not "
                        "allowed in the device policy.";
           return false;
diff --git a/connection_manager_unittest.cc b/connection_manager_unittest.cc
index 0bb5547..e26a686 100644
--- a/connection_manager_unittest.cc
+++ b/connection_manager_unittest.cc
@@ -21,7 +21,6 @@
 
 #include <base/logging.h>
 #include <brillo/any.h>
-#include <brillo/make_unique_ptr.h>
 #include <brillo/message_loops/fake_message_loop.h>
 #include <brillo/variant_dictionary.h>
 #include <gmock/gmock.h>
diff --git a/dbus_bindings/org.chromium.NetworkProxyService.dbus-xml b/dbus_bindings/org.chromium.NetworkProxyService.dbus-xml
deleted file mode 100644
index 90686ca..0000000
--- a/dbus_bindings/org.chromium.NetworkProxyService.dbus-xml
+++ /dev/null
@@ -1,13 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-
-<node name="/org/chromium/NetworkProxyService"
-      xmlns:tp="http://telepathy.freedesktop.org/wiki/DbusSpec#extensions-v0">
-  <interface name="org.chromium.NetworkProxyServiceInterface">
-    <method name="ResolveProxy">
-      <arg name="source_url" type="s" direction="in" />
-      <arg name="proxy_info" type="s" direction="out" />
-      <arg name="error_message" type="s" direction="out" />
-      <annotation name="org.chromium.DBus.Method.Kind" value="async" />
-    </method>
-  </interface>
-</node>
diff --git a/dbus_service.cc b/dbus_service.cc
index 0a7ad5b..3a35c71 100644
--- a/dbus_service.cc
+++ b/dbus_service.cc
@@ -25,6 +25,7 @@
 using brillo::ErrorPtr;
 using chromeos_update_engine::UpdateEngineService;
 using std::string;
+using update_engine::UpdateEngineStatus;
 
 DBusUpdateEngineService::DBusUpdateEngineService(SystemState* system_state)
     : common_(new UpdateEngineService{system_state}) {
@@ -172,14 +173,13 @@
                                         dbus::Bus::REQUIRE_PRIMARY);
 }
 
-void UpdateEngineAdaptor::SendStatusUpdate(int64_t last_checked_time,
-                                           double progress,
-                                           update_engine::UpdateStatus status,
-                                           const string& new_version,
-                                           int64_t new_size) {
-  const string str_status = UpdateStatusToString(status);
-  SendStatusUpdateSignal(
-      last_checked_time, progress, str_status, new_version, new_size);
+void UpdateEngineAdaptor::SendStatusUpdate(
+    const UpdateEngineStatus& update_engine_status) {
+  SendStatusUpdateSignal(update_engine_status.last_checked_time,
+                         update_engine_status.progress,
+                         UpdateStatusToString(update_engine_status.status),
+                         update_engine_status.new_version,
+                         update_engine_status.new_size);
 }
 
 }  // namespace chromeos_update_engine
diff --git a/dbus_service.h b/dbus_service.h
index 2b36ae9..b754661 100644
--- a/dbus_service.h
+++ b/dbus_service.h
@@ -167,11 +167,8 @@
   bool RequestOwnership();
 
   // ServiceObserverInterface overrides.
-  void SendStatusUpdate(int64_t last_checked_time,
-                        double progress,
-                        update_engine::UpdateStatus status,
-                        const std::string& new_version,
-                        int64_t new_size) override;
+  void SendStatusUpdate(
+      const update_engine::UpdateEngineStatus& update_engine_status) override;
 
   void SendPayloadApplicationComplete(ErrorCode error_code) override {}
 
diff --git a/fake_p2p_manager_configuration.h b/fake_p2p_manager_configuration.h
index 1bc1dc8..c1cf4f2 100644
--- a/fake_p2p_manager_configuration.h
+++ b/fake_p2p_manager_configuration.h
@@ -37,9 +37,7 @@
   }
 
   // P2PManager::Configuration override
-  base::FilePath GetP2PDir() override {
-    return p2p_dir_.path();
-  }
+  base::FilePath GetP2PDir() override { return p2p_dir_.GetPath(); }
 
   // P2PManager::Configuration override
   std::vector<std::string> GetInitctlArgs(bool is_start) override {
diff --git a/fake_system_state.cc b/fake_system_state.cc
index d51f775..1bfcafa 100644
--- a/fake_system_state.cc
+++ b/fake_system_state.cc
@@ -21,13 +21,13 @@
 // Mock the SystemStateInterface so that we could lie that
 // OOBE is completed even when there's no such marker file, etc.
 FakeSystemState::FakeSystemState()
-    : mock_update_attempter_(this, nullptr, nullptr),
+    : mock_update_attempter_(this, nullptr),
       mock_request_params_(this),
       fake_update_manager_(&fake_clock_),
       clock_(&fake_clock_),
       connection_manager_(&mock_connection_manager_),
       hardware_(&fake_hardware_),
-      metrics_lib_(&mock_metrics_lib_),
+      metrics_reporter_(&mock_metrics_reporter_),
       prefs_(&mock_prefs_),
       powerwash_safe_prefs_(&mock_powerwash_safe_prefs_),
       payload_state_(&mock_payload_state_),
diff --git a/fake_system_state.h b/fake_system_state.h
index 2225933..67ad3aa 100644
--- a/fake_system_state.h
+++ b/fake_system_state.h
@@ -27,6 +27,7 @@
 #include "update_engine/common/fake_hardware.h"
 #include "update_engine/common/mock_prefs.h"
 #include "update_engine/mock_connection_manager.h"
+#include "update_engine/mock_metrics_reporter.h"
 #include "update_engine/mock_omaha_request_params.h"
 #include "update_engine/mock_p2p_manager.h"
 #include "update_engine/mock_payload_state.h"
@@ -66,8 +67,9 @@
 
   inline HardwareInterface* hardware() override { return hardware_; }
 
-  inline MetricsLibraryInterface* metrics_lib() override {
-    return metrics_lib_;
+  inline MetricsReporterInterface* metrics_reporter() override {
+    CHECK(metrics_reporter_ != nullptr);
+    return metrics_reporter_;
   }
 
   inline PrefsInterface* prefs() override { return prefs_; }
@@ -122,8 +124,9 @@
     hardware_ = hardware ? hardware : &fake_hardware_;
   }
 
-  inline void set_metrics_lib(MetricsLibraryInterface* metrics_lib) {
-    metrics_lib_ = metrics_lib ? metrics_lib : &mock_metrics_lib_;
+  inline void set_metrics_reporter(MetricsReporterInterface* metrics_reporter) {
+    metrics_reporter_ =
+        metrics_reporter ? metrics_reporter : &mock_metrics_reporter_;
   }
 
   inline void set_prefs(PrefsInterface* prefs) {
@@ -187,9 +190,9 @@
     return &fake_hardware_;
   }
 
-  inline testing::NiceMock<MetricsLibraryMock>* mock_metrics_lib() {
-    CHECK(metrics_lib_ == &mock_metrics_lib_);
-    return &mock_metrics_lib_;
+  inline testing::NiceMock<MockMetricsReporter>* mock_metrics_reporter() {
+    CHECK(metrics_reporter_ == &mock_metrics_reporter_);
+    return &mock_metrics_reporter_;
   }
 
   inline testing::NiceMock<MockPrefs> *mock_prefs() {
@@ -233,7 +236,7 @@
   FakeClock fake_clock_;
   testing::NiceMock<MockConnectionManager> mock_connection_manager_;
   FakeHardware fake_hardware_;
-  testing::NiceMock<MetricsLibraryMock> mock_metrics_lib_;
+  testing::NiceMock<MockMetricsReporter> mock_metrics_reporter_;
   testing::NiceMock<MockPrefs> mock_prefs_;
   testing::NiceMock<MockPrefs> mock_powerwash_safe_prefs_;
   testing::NiceMock<MockPayloadState> mock_payload_state_;
@@ -249,7 +252,7 @@
   ClockInterface* clock_;
   ConnectionManagerInterface* connection_manager_;
   HardwareInterface* hardware_;
-  MetricsLibraryInterface* metrics_lib_;
+  MetricsReporterInterface* metrics_reporter_;
   PrefsInterface* prefs_;
   PrefsInterface* powerwash_safe_prefs_;
   PayloadStateInterface* payload_state_;
diff --git a/hardware_android.cc b/hardware_android.cc
index 9490c24..947b13a 100644
--- a/hardware_android.cc
+++ b/hardware_android.cc
@@ -21,19 +21,22 @@
 #include <sys/types.h>
 
 #include <algorithm>
+#include <memory>
 
 #include <bootloader.h>
 
+#include <android-base/properties.h>
 #include <base/files/file_util.h>
 #include <base/strings/stringprintf.h>
-#include <brillo/make_unique_ptr.h>
-#include <cutils/properties.h>
 
 #include "update_engine/common/hardware.h"
 #include "update_engine/common/platform_constants.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/utils_android.h"
 
+using android::base::GetBoolProperty;
+using android::base::GetIntProperty;
+using android::base::GetProperty;
 using std::string;
 
 namespace chromeos_update_engine {
@@ -72,8 +75,7 @@
            std::min(message.size(), sizeof(boot.recovery) - 1));
   }
 
-  int fd =
-      HANDLE_EINTR(open(misc_device.value().c_str(), O_WRONLY | O_SYNC, 0600));
+  int fd = HANDLE_EINTR(open(misc_device.value().c_str(), O_WRONLY | O_SYNC));
   if (fd < 0) {
     PLOG(ERROR) << "Opening misc";
     return false;
@@ -96,7 +98,7 @@
 
 // Factory defined in hardware.h.
 std::unique_ptr<HardwareInterface> CreateHardware() {
-  return brillo::make_unique_ptr(new HardwareAndroid());
+  return std::make_unique<HardwareAndroid>();
 }
 
 }  // namespace hardware
@@ -122,7 +124,7 @@
   //
   // In case of a non-bool value, we take the most restrictive option and
   // assume we are in an official-build.
-  return property_get_bool("ro.secure", 1) != 0;
+  return GetBoolProperty("ro.secure", true);
 }
 
 bool HardwareAndroid::IsNormalBootMode() const {
@@ -130,7 +132,7 @@
   // update_engine will allow extra developers options, such as providing a
   // different update URL. In case of error, we assume the build is in
   // normal-mode.
-  return property_get_bool("ro.debuggable", 0) != 1;
+  return !GetBoolProperty("ro.debuggable", false);
 }
 
 bool HardwareAndroid::AreDevFeaturesEnabled() const {
@@ -150,26 +152,19 @@
 }
 
 string HardwareAndroid::GetHardwareClass() const {
-  char manufacturer[PROPERTY_VALUE_MAX];
-  char sku[PROPERTY_VALUE_MAX];
-  char revision[PROPERTY_VALUE_MAX];
-  property_get(kPropBootHardwareSKU, sku, "");
-  property_get(kPropProductManufacturer, manufacturer, "");
-  property_get(kPropBootRevision, revision, "");
+  auto manufacturer = GetProperty(kPropProductManufacturer, "");
+  auto sku = GetProperty(kPropBootHardwareSKU, "");
+  auto revision = GetProperty(kPropBootRevision, "");
 
-  return base::StringPrintf("%s:%s:%s", manufacturer, sku, revision);
+  return manufacturer + ":" + sku + ":" + revision;
 }
 
 string HardwareAndroid::GetFirmwareVersion() const {
-  char bootloader[PROPERTY_VALUE_MAX];
-  property_get(kPropBootBootloader, bootloader, "");
-  return bootloader;
+  return GetProperty(kPropBootBootloader, "");
 }
 
 string HardwareAndroid::GetECVersion() const {
-  char baseband[PROPERTY_VALUE_MAX];
-  property_get(kPropBootBaseband, baseband, "");
-  return baseband;
+  return GetProperty(kPropBootBaseband, "");
 }
 
 int HardwareAndroid::GetPowerwashCount() const {
@@ -202,7 +197,17 @@
 }
 
 int64_t HardwareAndroid::GetBuildTimestamp() const {
-  return property_get_int64(kPropBuildDateUTC, 0);
+  return GetIntProperty<int64_t>(kPropBuildDateUTC, 0);
+}
+
+bool HardwareAndroid::GetFirstActiveOmahaPingSent() const {
+  LOG(WARNING) << "STUB: Assuming first active omaha was never set.";
+  return false;
+}
+
+void HardwareAndroid::SetFirstActiveOmahaPingSent() {
+  LOG(WARNING) << "STUB: Assuming first active omaha is never set.";
+  return;
 }
 
 }  // namespace chromeos_update_engine
diff --git a/hardware_android.h b/hardware_android.h
index 80fd9df..ca90b62 100644
--- a/hardware_android.h
+++ b/hardware_android.h
@@ -48,6 +48,8 @@
   bool GetNonVolatileDirectory(base::FilePath* path) const override;
   bool GetPowerwashSafeDirectory(base::FilePath* path) const override;
   int64_t GetBuildTimestamp() const override;
+  bool GetFirstActiveOmahaPingSent() const override;
+  void SetFirstActiveOmahaPingSent() override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(HardwareAndroid);
diff --git a/hardware_chromeos.cc b/hardware_chromeos.cc
index f0f3ea9..f2bb28a 100644
--- a/hardware_chromeos.cc
+++ b/hardware_chromeos.cc
@@ -22,7 +22,6 @@
 #include <base/strings/string_number_conversions.h>
 #include <base/strings/string_util.h>
 #include <brillo/key_value_store.h>
-#include <brillo/make_unique_ptr.h>
 #include <debugd/dbus-constants.h>
 #include <vboot/crossystem.h>
 
@@ -69,6 +68,8 @@
 // UpdateManager config options:
 const char* kConfigOptsIsOOBEEnabled = "is_oobe_enabled";
 
+const char* kActivePingKey = "first_active_omaha_ping_sent";
+
 }  // namespace
 
 namespace chromeos_update_engine {
@@ -253,4 +254,49 @@
     is_oobe_enabled_ = true;  // Default value.
 }
 
+bool HardwareChromeOS::GetFirstActiveOmahaPingSent() const {
+  int exit_code = 0;
+  string active_ping_str;
+  vector<string> cmd = { "vpd_get_value", kActivePingKey };
+  if (!Subprocess::SynchronousExec(cmd, &exit_code, &active_ping_str) ||
+      exit_code) {
+    LOG(ERROR) << "Failed to get vpd key for " << kActivePingKey
+               << " with exit code: " << exit_code;
+    return false;
+  }
+
+  base::TrimWhitespaceASCII(active_ping_str,
+                            base::TRIM_ALL,
+                            &active_ping_str);
+  int active_ping;
+  if (active_ping_str.empty() ||
+      !base::StringToInt(active_ping_str, &active_ping)) {
+    LOG(INFO) << "Failed to parse active_ping value: " << active_ping_str;
+    return false;
+  }
+  return static_cast<bool>(active_ping);
+}
+
+void HardwareChromeOS::SetFirstActiveOmahaPingSent() {
+  int exit_code = 0;
+  string output;
+  vector<string> vpd_set_cmd = {
+    "vpd", "-i", "RW_VPD", "-s", string(kActivePingKey) + "=1" };
+  if (!Subprocess::SynchronousExec(vpd_set_cmd, &exit_code, &output) ||
+      exit_code) {
+    LOG(ERROR) << "Failed to set vpd key for " << kActivePingKey
+               << " with exit code: " << exit_code
+               << " with error: " << output;
+    return;
+  }
+
+  vector<string> vpd_dump_cmd = { "dump_vpd_log", "--force" };
+  if (!Subprocess::SynchronousExec(vpd_dump_cmd, &exit_code, &output) ||
+      exit_code) {
+    LOG(ERROR) << "Failed to cache " << kActivePingKey<< " using dump_vpd_log"
+               << " with exit code: " << exit_code
+               << " with error: " << output;
+  }
+}
+
 }  // namespace chromeos_update_engine
diff --git a/hardware_chromeos.h b/hardware_chromeos.h
index a756a9b..0cf1214 100644
--- a/hardware_chromeos.h
+++ b/hardware_chromeos.h
@@ -52,6 +52,8 @@
   bool GetNonVolatileDirectory(base::FilePath* path) const override;
   bool GetPowerwashSafeDirectory(base::FilePath* path) const override;
   int64_t GetBuildTimestamp() const override;
+  bool GetFirstActiveOmahaPingSent() const override;
+  void SetFirstActiveOmahaPingSent() override;
 
  private:
   friend class HardwareChromeOSTest;
diff --git a/hardware_chromeos_unittest.cc b/hardware_chromeos_unittest.cc
index a6bad54..162dec4 100644
--- a/hardware_chromeos_unittest.cc
+++ b/hardware_chromeos_unittest.cc
@@ -37,21 +37,22 @@
   void SetUp() override { ASSERT_TRUE(root_dir_.CreateUniqueTempDir()); }
 
   void WriteStatefulConfig(const string& config) {
-    base::FilePath kFile(root_dir_.path().value() + kStatefulPartition +
+    base::FilePath kFile(root_dir_.GetPath().value() + kStatefulPartition +
                          "/etc/update_manager.conf");
     ASSERT_TRUE(base::CreateDirectory(kFile.DirName()));
     ASSERT_TRUE(WriteFileString(kFile.value(), config));
   }
 
   void WriteRootfsConfig(const string& config) {
-    base::FilePath kFile(root_dir_.path().value() + "/etc/update_manager.conf");
+    base::FilePath kFile(root_dir_.GetPath().value() +
+                         "/etc/update_manager.conf");
     ASSERT_TRUE(base::CreateDirectory(kFile.DirName()));
     ASSERT_TRUE(WriteFileString(kFile.value(), config));
   }
 
   // Helper method to call HardwareChromeOS::LoadConfig with the test directory.
   void CallLoadConfig(bool normal_mode) {
-    hardware_.LoadConfig(root_dir_.path().value(), normal_mode);
+    hardware_.LoadConfig(root_dir_.GetPath().value(), normal_mode);
   }
 
   HardwareChromeOS hardware_;
diff --git a/image_properties.h b/image_properties.h
index 4f94eeb..f8fe095 100644
--- a/image_properties.h
+++ b/image_properties.h
@@ -41,6 +41,9 @@
   // The system version of this image.
   std::string system_version;
 
+  // The version of all product components in key values pairs.
+  std::string product_components;
+
   // A unique string that identifies this build. Normally a combination of the
   // the version, signing keys and build target.
   std::string build_fingerprint;
@@ -76,8 +79,8 @@
 // value may be returned instead.
 ImageProperties LoadImageProperties(SystemState* system_state);
 
-// Loads the mutable image properties from the stateful partition if found or the
-// system image otherwise.
+// Loads the mutable image properties from the stateful partition if found or
+// the system image otherwise.
 MutableImageProperties LoadMutableImageProperties(SystemState* system_state);
 
 // Stores the mutable image properties in the stateful partition. Returns
@@ -85,6 +88,9 @@
 bool StoreMutableImageProperties(SystemState* system_state,
                                  const MutableImageProperties& properties);
 
+// Logs the image properties.
+void LogImageProperties();
+
 // Sets the root_prefix used to load files from during unittests to
 // |test_root_prefix|. Passing a nullptr value resets it to the default.
 namespace test {
diff --git a/image_properties_android.cc b/image_properties_android.cc
index d52c40b..1ec425d 100644
--- a/image_properties_android.cc
+++ b/image_properties_android.cc
@@ -18,17 +18,19 @@
 
 #include <string>
 
+#include <android-base/properties.h>
 #include <base/logging.h>
 #include <brillo/osrelease_reader.h>
 #include <brillo/strings/string_utils.h>
-#include <cutils/properties.h>
 
 #include "update_engine/common/boot_control_interface.h"
 #include "update_engine/common/constants.h"
 #include "update_engine/common/platform_constants.h"
 #include "update_engine/common/prefs_interface.h"
+#include "update_engine/common/utils.h"
 #include "update_engine/system_state.h"
 
+using android::base::GetProperty;
 using std::string;
 
 namespace chromeos_update_engine {
@@ -41,6 +43,10 @@
 const char kSystemId[] = "system_id";
 const char kSystemVersion[] = "system_version";
 
+// The path to the product_components file which stores the version of each
+// components in OEM partition.
+const char kProductComponentsPath[] = "/oem/os-release.d/product_components";
+
 // Prefs used to store the target channel and powerwash settings.
 const char kPrefsImgPropChannelName[] = "img-prop-channel-name";
 const char kPrefsImgPropPowerwashAllowed[] = "img-prop-powerwash-allowed";
@@ -96,16 +102,12 @@
   result.version = GetStringWithDefault(osrelease, kProductVersion, "0.0.0.0");
   result.system_version =
       GetStringWithDefault(osrelease, kSystemVersion, "0.0.0.0");
+  // Can't read it with OsReleaseReader because it has multiple lines.
+  utils::ReadFile(kProductComponentsPath, &result.product_components);
 
-  char prop[PROPERTY_VALUE_MAX];
-  property_get(kPropProductName, prop, "brillo");
-  result.board = prop;
-
-  property_get(kPropBuildFingerprint, prop, "none");
-  result.build_fingerprint = prop;
-
-  property_get(kPropBuildType, prop, "");
-  result.build_type = prop;
+  result.board = GetProperty(kPropProductName, "brillo");
+  result.build_fingerprint = GetProperty(kPropBuildFingerprint, "none");
+  result.build_type = GetProperty(kPropBuildType, "");
 
   // Brillo images don't have a channel assigned. We stored the name of the
   // channel where we got the image from in prefs at the time of the update, so
@@ -147,4 +149,8 @@
                         properties.is_powerwash_allowed));
 }
 
+void LogImageProperties() {
+  // TODO(*): Implement this.
+}
+
 }  // namespace chromeos_update_engine
diff --git a/image_properties_android_unittest.cc b/image_properties_android_unittest.cc
index 9bbb8b0..7327554 100644
--- a/image_properties_android_unittest.cc
+++ b/image_properties_android_unittest.cc
@@ -36,9 +36,9 @@
   void SetUp() override {
     // Create a uniquely named test directory.
     ASSERT_TRUE(tempdir_.CreateUniqueTempDir());
-    osrelease_dir_ = tempdir_.path().Append("etc/os-release.d");
+    osrelease_dir_ = tempdir_.GetPath().Append("etc/os-release.d");
     EXPECT_TRUE(base::CreateDirectory(osrelease_dir_));
-    test::SetImagePropertiesRootPrefix(tempdir_.path().value().c_str());
+    test::SetImagePropertiesRootPrefix(tempdir_.GetPath().value().c_str());
   }
 
   void WriteOsRelease(const string& key, const string& value) {
diff --git a/image_properties_chromeos.cc b/image_properties_chromeos.cc
index 6bab63f..39ddeb3 100644
--- a/image_properties_chromeos.cc
+++ b/image_properties_chromeos.cc
@@ -26,6 +26,7 @@
 #include "update_engine/common/constants.h"
 #include "update_engine/common/hardware_interface.h"
 #include "update_engine/common/platform_constants.h"
+#include "update_engine/common/utils.h"
 #include "update_engine/system_state.h"
 
 namespace {
@@ -149,4 +150,17 @@
   return lsb_release.Save(path);
 }
 
+void LogImageProperties() {
+  std::string lsb_release;
+  if (utils::ReadFile(kLsbRelease, &lsb_release)) {
+    LOG(INFO) << "lsb-release inside the old rootfs:\n" << lsb_release;
+  }
+
+  std::string stateful_lsb_release;
+  if (utils::ReadFile(std::string(kStatefulPartition) + kLsbRelease,
+                      &stateful_lsb_release)) {
+    LOG(INFO) << "stateful lsb-release:\n" << stateful_lsb_release;
+  }
+}
+
 }  // namespace chromeos_update_engine
diff --git a/image_properties_chromeos_unittest.cc b/image_properties_chromeos_unittest.cc
index 12c2039..d9ed688 100644
--- a/image_properties_chromeos_unittest.cc
+++ b/image_properties_chromeos_unittest.cc
@@ -36,10 +36,10 @@
   void SetUp() override {
     // Create a uniquely named test directory.
     ASSERT_TRUE(tempdir_.CreateUniqueTempDir());
-    EXPECT_TRUE(base::CreateDirectory(tempdir_.path().Append("etc")));
-    EXPECT_TRUE(base::CreateDirectory(
-        base::FilePath(tempdir_.path().value() + kStatefulPartition + "/etc")));
-    test::SetImagePropertiesRootPrefix(tempdir_.path().value().c_str());
+    EXPECT_TRUE(base::CreateDirectory(tempdir_.GetPath().Append("etc")));
+    EXPECT_TRUE(base::CreateDirectory(base::FilePath(
+        tempdir_.GetPath().value() + kStatefulPartition + "/etc")));
+    test::SetImagePropertiesRootPrefix(tempdir_.GetPath().value().c_str());
     SetLockDown(false);
   }
 
@@ -54,12 +54,13 @@
 };
 
 TEST_F(ImagePropertiesTest, SimpleTest) {
-  ASSERT_TRUE(WriteFileString(tempdir_.path().Append("etc/lsb-release").value(),
-                              "CHROMEOS_RELEASE_BOARD=arm-generic\n"
-                              "CHROMEOS_RELEASE_FOO=bar\n"
-                              "CHROMEOS_RELEASE_VERSION=0.2.2.3\n"
-                              "CHROMEOS_RELEASE_TRACK=dev-channel\n"
-                              "CHROMEOS_AUSERVER=http://www.google.com"));
+  ASSERT_TRUE(
+      WriteFileString(tempdir_.GetPath().Append("etc/lsb-release").value(),
+                      "CHROMEOS_RELEASE_BOARD=arm-generic\n"
+                      "CHROMEOS_RELEASE_FOO=bar\n"
+                      "CHROMEOS_RELEASE_VERSION=0.2.2.3\n"
+                      "CHROMEOS_RELEASE_TRACK=dev-channel\n"
+                      "CHROMEOS_AUSERVER=http://www.google.com"));
   ImageProperties props = LoadImageProperties(&fake_system_state_);
   EXPECT_EQ("arm-generic", props.board);
   EXPECT_EQ("{87efface-864d-49a5-9bb3-4b050a7c227a}", props.product_id);
@@ -70,7 +71,7 @@
 
 TEST_F(ImagePropertiesTest, AppIDTest) {
   ASSERT_TRUE(WriteFileString(
-      tempdir_.path().Append("etc/lsb-release").value(),
+      tempdir_.GetPath().Append("etc/lsb-release").value(),
       "CHROMEOS_RELEASE_APPID={58c35cef-9d30-476e-9098-ce20377d535d}"));
   ImageProperties props = LoadImageProperties(&fake_system_state_);
   EXPECT_EQ("{58c35cef-9d30-476e-9098-ce20377d535d}", props.product_id);
@@ -78,7 +79,7 @@
 
 TEST_F(ImagePropertiesTest, ConfusingReleaseTest) {
   ASSERT_TRUE(
-      WriteFileString(tempdir_.path().Append("etc/lsb-release").value(),
+      WriteFileString(tempdir_.GetPath().Append("etc/lsb-release").value(),
                       "CHROMEOS_RELEASE_FOO=CHROMEOS_RELEASE_VERSION=1.2.3.4\n"
                       "CHROMEOS_RELEASE_VERSION=0.2.2.3"));
   ImageProperties props = LoadImageProperties(&fake_system_state_);
@@ -91,13 +92,14 @@
 }
 
 TEST_F(ImagePropertiesTest, OverrideTest) {
-  ASSERT_TRUE(WriteFileString(tempdir_.path().Append("etc/lsb-release").value(),
-                              "CHROMEOS_RELEASE_BOARD=arm-generic\n"
-                              "CHROMEOS_RELEASE_FOO=bar\n"
-                              "CHROMEOS_RELEASE_TRACK=dev-channel\n"
-                              "CHROMEOS_AUSERVER=http://www.google.com"));
+  ASSERT_TRUE(
+      WriteFileString(tempdir_.GetPath().Append("etc/lsb-release").value(),
+                      "CHROMEOS_RELEASE_BOARD=arm-generic\n"
+                      "CHROMEOS_RELEASE_FOO=bar\n"
+                      "CHROMEOS_RELEASE_TRACK=dev-channel\n"
+                      "CHROMEOS_AUSERVER=http://www.google.com"));
   ASSERT_TRUE(WriteFileString(
-      tempdir_.path().value() + kStatefulPartition + "/etc/lsb-release",
+      tempdir_.GetPath().value() + kStatefulPartition + "/etc/lsb-release",
       "CHROMEOS_RELEASE_BOARD=x86-generic\n"
       "CHROMEOS_RELEASE_TRACK=beta-channel\n"
       "CHROMEOS_AUSERVER=https://www.google.com"));
@@ -111,13 +113,14 @@
 }
 
 TEST_F(ImagePropertiesTest, OverrideLockDownTest) {
-  ASSERT_TRUE(WriteFileString(tempdir_.path().Append("etc/lsb-release").value(),
-                              "CHROMEOS_RELEASE_BOARD=arm-generic\n"
-                              "CHROMEOS_RELEASE_FOO=bar\n"
-                              "CHROMEOS_RELEASE_TRACK=dev-channel\n"
-                              "CHROMEOS_AUSERVER=https://www.google.com"));
+  ASSERT_TRUE(
+      WriteFileString(tempdir_.GetPath().Append("etc/lsb-release").value(),
+                      "CHROMEOS_RELEASE_BOARD=arm-generic\n"
+                      "CHROMEOS_RELEASE_FOO=bar\n"
+                      "CHROMEOS_RELEASE_TRACK=dev-channel\n"
+                      "CHROMEOS_AUSERVER=https://www.google.com"));
   ASSERT_TRUE(WriteFileString(
-      tempdir_.path().value() + kStatefulPartition + "/etc/lsb-release",
+      tempdir_.GetPath().value() + kStatefulPartition + "/etc/lsb-release",
       "CHROMEOS_RELEASE_BOARD=x86-generic\n"
       "CHROMEOS_RELEASE_TRACK=stable-channel\n"
       "CHROMEOS_AUSERVER=http://www.google.com"));
@@ -132,32 +135,35 @@
 }
 
 TEST_F(ImagePropertiesTest, BoardAppIdUsedForNonCanaryChannelTest) {
-  ASSERT_TRUE(WriteFileString(tempdir_.path().Append("etc/lsb-release").value(),
-                              "CHROMEOS_RELEASE_APPID=r\n"
-                              "CHROMEOS_BOARD_APPID=b\n"
-                              "CHROMEOS_CANARY_APPID=c\n"
-                              "CHROMEOS_RELEASE_TRACK=stable-channel\n"));
+  ASSERT_TRUE(
+      WriteFileString(tempdir_.GetPath().Append("etc/lsb-release").value(),
+                      "CHROMEOS_RELEASE_APPID=r\n"
+                      "CHROMEOS_BOARD_APPID=b\n"
+                      "CHROMEOS_CANARY_APPID=c\n"
+                      "CHROMEOS_RELEASE_TRACK=stable-channel\n"));
   ImageProperties props = LoadImageProperties(&fake_system_state_);
   EXPECT_EQ("stable-channel", props.current_channel);
   EXPECT_EQ("b", props.product_id);
 }
 
 TEST_F(ImagePropertiesTest, CanaryAppIdUsedForCanaryChannelTest) {
-  ASSERT_TRUE(WriteFileString(tempdir_.path().Append("etc/lsb-release").value(),
-                              "CHROMEOS_RELEASE_APPID=r\n"
-                              "CHROMEOS_BOARD_APPID=b\n"
-                              "CHROMEOS_CANARY_APPID=c\n"
-                              "CHROMEOS_RELEASE_TRACK=canary-channel\n"));
+  ASSERT_TRUE(
+      WriteFileString(tempdir_.GetPath().Append("etc/lsb-release").value(),
+                      "CHROMEOS_RELEASE_APPID=r\n"
+                      "CHROMEOS_BOARD_APPID=b\n"
+                      "CHROMEOS_CANARY_APPID=c\n"
+                      "CHROMEOS_RELEASE_TRACK=canary-channel\n"));
   ImageProperties props = LoadImageProperties(&fake_system_state_);
   EXPECT_EQ("canary-channel", props.current_channel);
   EXPECT_EQ("c", props.canary_product_id);
 }
 
 TEST_F(ImagePropertiesTest, ReleaseAppIdUsedAsDefaultTest) {
-  ASSERT_TRUE(WriteFileString(tempdir_.path().Append("etc/lsb-release").value(),
-                              "CHROMEOS_RELEASE_APPID=r\n"
-                              "CHROMEOS_CANARY_APPID=c\n"
-                              "CHROMEOS_RELEASE_TRACK=stable-channel\n"));
+  ASSERT_TRUE(
+      WriteFileString(tempdir_.GetPath().Append("etc/lsb-release").value(),
+                      "CHROMEOS_RELEASE_APPID=r\n"
+                      "CHROMEOS_CANARY_APPID=c\n"
+                      "CHROMEOS_RELEASE_TRACK=stable-channel\n"));
   ImageProperties props = LoadImageProperties(&fake_system_state_);
   EXPECT_EQ("stable-channel", props.current_channel);
   EXPECT_EQ("r", props.product_id);
diff --git a/libcurl_http_fetcher.cc b/libcurl_http_fetcher.cc
index eac6ea0..87f30ad 100644
--- a/libcurl_http_fetcher.cc
+++ b/libcurl_http_fetcher.cc
@@ -272,7 +272,7 @@
     } else if (base::StartsWith(
                    url_, "https://", base::CompareCase::INSENSITIVE_ASCII)) {
       SetCurlOptionsForHttps();
-#if !defined(__CHROMEOS__) && !defined(__BRILLO__)
+#if !USE_OMAHA
     } else if (base::StartsWith(
                    url_, "file://", base::CompareCase::INSENSITIVE_ASCII)) {
       SetCurlOptionsForFile();
diff --git a/main.cc b/main.cc
index 4275bc1..0b96307 100644
--- a/main.cc
+++ b/main.cc
@@ -38,6 +38,7 @@
 namespace chromeos_update_engine {
 namespace {
 
+#ifndef __ANDROID__
 void SetupLogSymlink(const string& symlink_path, const string& log_path) {
   // TODO(petkov): To ensure a smooth transition between non-timestamped and
   // timestamped logs, move an existing log to start the first timestamped
@@ -75,30 +76,41 @@
   SetupLogSymlink(kLogSymlink, kLogPath);
   return kLogSymlink;
 }
+#endif  // __ANDROID__
 
-void SetupLogging(bool log_to_std_err) {
-  string log_file;
+void SetupLogging(bool log_to_system, bool log_to_file) {
   logging::LoggingSettings log_settings;
   log_settings.lock_log = logging::DONT_LOCK_LOG_FILE;
-  log_settings.delete_old = logging::APPEND_TO_OLD_LOG_FILE;
+  log_settings.logging_dest = static_cast<logging::LoggingDestination>(
+      (log_to_system ? logging::LOG_TO_SYSTEM_DEBUG_LOG : 0) |
+      (log_to_file ? logging::LOG_TO_FILE : 0));
+  log_settings.log_file = nullptr;
 
-  if (log_to_std_err) {
-    // Log to stderr initially.
-    log_settings.log_file = nullptr;
-    log_settings.logging_dest = logging::LOG_TO_SYSTEM_DEBUG_LOG;
-  } else {
+  string log_file;
+  if (log_to_file) {
+#ifdef __ANDROID__
+    log_file = "/data/misc/update_engine_log/update_engine.log";
+    log_settings.delete_old = logging::DELETE_OLD_LOG_FILE;
+#else
     log_file = SetupLogFile("/var/log");
+    log_settings.delete_old = logging::APPEND_TO_OLD_LOG_FILE;
+#endif  // __ANDROID__
     log_settings.log_file = log_file.c_str();
-    log_settings.logging_dest = logging::LOG_TO_FILE;
   }
-
   logging::InitLogging(log_settings);
+
+#ifdef __ANDROID__
+  // The log file will have AID_LOG as group ID; this GID is inherited from the
+  // parent directory "/data/misc/update_engine_log" which sets the SGID bit.
+  chmod(log_file.c_str(), 0640);
+#endif
 }
 
 }  // namespace
 }  // namespace chromeos_update_engine
 
 int main(int argc, char** argv) {
+  DEFINE_bool(logtofile, false, "Write logs to a file in log_dir.");
   DEFINE_bool(logtostderr, false,
               "Write logs to stderr instead of to a file in log_dir.");
   DEFINE_bool(foreground, false,
@@ -106,7 +118,15 @@
 
   chromeos_update_engine::Terminator::Init();
   brillo::FlagHelper::Init(argc, argv, "Chromium OS Update Engine");
-  chromeos_update_engine::SetupLogging(FLAGS_logtostderr);
+
+  // We have two logging flags "--logtostderr" and "--logtofile"; and the logic
+  // to choose the logging destination is:
+  // 1. --logtostderr --logtofile -> logs to both
+  // 2. --logtostderr             -> logs to system debug
+  // 3. --logtofile or no flags   -> logs to file
+  bool log_to_system = FLAGS_logtostderr;
+  bool log_to_file = FLAGS_logtofile || !FLAGS_logtostderr;
+  chromeos_update_engine::SetupLogging(log_to_system, log_to_file);
   if (!FLAGS_foreground)
     PLOG_IF(FATAL, daemon(0, 0) == 1) << "daemon() failed";
 
diff --git a/metrics.cc b/metrics.cc
deleted file mode 100644
index 742ba7e..0000000
--- a/metrics.cc
+++ /dev/null
@@ -1,526 +0,0 @@
-//
-// Copyright (C) 2014 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-
-#include "update_engine/metrics.h"
-
-#include <string>
-
-#include <base/logging.h>
-#include <metrics/metrics_library.h>
-
-#include "update_engine/common/clock_interface.h"
-#include "update_engine/common/constants.h"
-#include "update_engine/common/prefs_interface.h"
-#include "update_engine/common/utils.h"
-#include "update_engine/metrics_utils.h"
-#include "update_engine/system_state.h"
-
-using std::string;
-
-namespace chromeos_update_engine {
-
-namespace metrics {
-
-// UpdateEngine.Daily.* metrics.
-const char kMetricDailyOSAgeDays[] = "UpdateEngine.Daily.OSAgeDays";
-
-// UpdateEngine.Check.* metrics.
-const char kMetricCheckDownloadErrorCode[] =
-    "UpdateEngine.Check.DownloadErrorCode";
-const char kMetricCheckReaction[] = "UpdateEngine.Check.Reaction";
-const char kMetricCheckResult[] = "UpdateEngine.Check.Result";
-const char kMetricCheckTimeSinceLastCheckMinutes[] =
-    "UpdateEngine.Check.TimeSinceLastCheckMinutes";
-const char kMetricCheckTimeSinceLastCheckUptimeMinutes[] =
-    "UpdateEngine.Check.TimeSinceLastCheckUptimeMinutes";
-
-// UpdateEngine.Attempt.* metrics.
-const char kMetricAttemptNumber[] = "UpdateEngine.Attempt.Number";
-const char kMetricAttemptPayloadType[] =
-    "UpdateEngine.Attempt.PayloadType";
-const char kMetricAttemptPayloadSizeMiB[] =
-    "UpdateEngine.Attempt.PayloadSizeMiB";
-const char kMetricAttemptConnectionType[] =
-    "UpdateEngine.Attempt.ConnectionType";
-const char kMetricAttemptDurationMinutes[] =
-    "UpdateEngine.Attempt.DurationMinutes";
-const char kMetricAttemptDurationUptimeMinutes[] =
-    "UpdateEngine.Attempt.DurationUptimeMinutes";
-const char kMetricAttemptTimeSinceLastAttemptMinutes[] =
-    "UpdateEngine.Attempt.TimeSinceLastAttemptMinutes";
-const char kMetricAttemptTimeSinceLastAttemptUptimeMinutes[] =
-    "UpdateEngine.Attempt.TimeSinceLastAttemptUptimeMinutes";
-const char kMetricAttemptPayloadBytesDownloadedMiB[] =
-    "UpdateEngine.Attempt.PayloadBytesDownloadedMiB";
-const char kMetricAttemptPayloadDownloadSpeedKBps[] =
-    "UpdateEngine.Attempt.PayloadDownloadSpeedKBps";
-const char kMetricAttemptDownloadSource[] =
-    "UpdateEngine.Attempt.DownloadSource";
-const char kMetricAttemptResult[] =
-    "UpdateEngine.Attempt.Result";
-const char kMetricAttemptInternalErrorCode[] =
-    "UpdateEngine.Attempt.InternalErrorCode";
-const char kMetricAttemptDownloadErrorCode[] =
-    "UpdateEngine.Attempt.DownloadErrorCode";
-
-// UpdateEngine.SuccessfulUpdate.* metrics.
-const char kMetricSuccessfulUpdateAttemptCount[] =
-    "UpdateEngine.SuccessfulUpdate.AttemptCount";
-const char kMetricSuccessfulUpdateBytesDownloadedMiB[] =
-    "UpdateEngine.SuccessfulUpdate.BytesDownloadedMiB";
-const char kMetricSuccessfulUpdateDownloadOverheadPercentage[] =
-    "UpdateEngine.SuccessfulUpdate.DownloadOverheadPercentage";
-const char kMetricSuccessfulUpdateDownloadSourcesUsed[] =
-    "UpdateEngine.SuccessfulUpdate.DownloadSourcesUsed";
-const char kMetricSuccessfulUpdatePayloadType[] =
-    "UpdateEngine.SuccessfulUpdate.PayloadType";
-const char kMetricSuccessfulUpdatePayloadSizeMiB[] =
-    "UpdateEngine.SuccessfulUpdate.PayloadSizeMiB";
-const char kMetricSuccessfulUpdateRebootCount[] =
-    "UpdateEngine.SuccessfulUpdate.RebootCount";
-const char kMetricSuccessfulUpdateTotalDurationMinutes[] =
-    "UpdateEngine.SuccessfulUpdate.TotalDurationMinutes";
-const char kMetricSuccessfulUpdateUpdatesAbandonedCount[] =
-    "UpdateEngine.SuccessfulUpdate.UpdatesAbandonedCount";
-const char kMetricSuccessfulUpdateUrlSwitchCount[] =
-    "UpdateEngine.SuccessfulUpdate.UrlSwitchCount";
-
-// UpdateEngine.Rollback.* metric.
-const char kMetricRollbackResult[] = "UpdateEngine.Rollback.Result";
-
-// UpdateEngine.CertificateCheck.* metrics.
-const char kMetricCertificateCheckUpdateCheck[] =
-    "UpdateEngine.CertificateCheck.UpdateCheck";
-const char kMetricCertificateCheckDownload[] =
-    "UpdateEngine.CertificateCheck.Download";
-
-// UpdateEngine.* metrics.
-const char kMetricFailedUpdateCount[] = "UpdateEngine.FailedUpdateCount";
-const char kMetricInstallDateProvisioningSource[] =
-    "UpdateEngine.InstallDateProvisioningSource";
-const char kMetricTimeToRebootMinutes[] =
-    "UpdateEngine.TimeToRebootMinutes";
-
-void ReportDailyMetrics(SystemState *system_state,
-                        base::TimeDelta os_age) {
-  string metric = metrics::kMetricDailyOSAgeDays;
-  LOG(INFO) << "Uploading " << utils::FormatTimeDelta(os_age)
-            << " for metric " <<  metric;
-  system_state->metrics_lib()->SendToUMA(
-      metric,
-      static_cast<int>(os_age.InDays()),
-      0,     // min: 0 days
-      6*30,  // max: 6 months (approx)
-      50);   // num_buckets
-}
-
-void ReportUpdateCheckMetrics(SystemState *system_state,
-                              CheckResult result,
-                              CheckReaction reaction,
-                              DownloadErrorCode download_error_code) {
-  string metric;
-  int value;
-  int max_value;
-
-  if (result != metrics::CheckResult::kUnset) {
-    metric = metrics::kMetricCheckResult;
-    value = static_cast<int>(result);
-    max_value = static_cast<int>(metrics::CheckResult::kNumConstants) - 1;
-    LOG(INFO) << "Sending " << value << " for metric " << metric << " (enum)";
-    system_state->metrics_lib()->SendEnumToUMA(metric, value, max_value);
-  }
-  if (reaction != metrics::CheckReaction::kUnset) {
-    metric = metrics::kMetricCheckReaction;
-    value = static_cast<int>(reaction);
-    max_value = static_cast<int>(metrics::CheckReaction::kNumConstants) - 1;
-    LOG(INFO) << "Sending " << value << " for metric " << metric << " (enum)";
-    system_state->metrics_lib()->SendEnumToUMA(metric, value, max_value);
-  }
-  if (download_error_code != metrics::DownloadErrorCode::kUnset) {
-    metric = metrics::kMetricCheckDownloadErrorCode;
-    value = static_cast<int>(download_error_code);
-    LOG(INFO) << "Sending " << value << " for metric " << metric << " (sparse)";
-    system_state->metrics_lib()->SendSparseToUMA(metric, value);
-  }
-
-  base::TimeDelta time_since_last;
-  if (metrics_utils::WallclockDurationHelper(
-          system_state,
-          kPrefsMetricsCheckLastReportingTime,
-          &time_since_last)) {
-    metric = kMetricCheckTimeSinceLastCheckMinutes;
-    LOG(INFO) << "Sending " << utils::FormatTimeDelta(time_since_last)
-              << " for metric " << metric;
-    system_state->metrics_lib()->SendToUMA(
-        metric,
-        time_since_last.InMinutes(),
-        0,         // min: 0 min
-        30*24*60,  // max: 30 days
-        50);       // num_buckets
-  }
-
-  base::TimeDelta uptime_since_last;
-  static int64_t uptime_since_last_storage = 0;
-  if (metrics_utils::MonotonicDurationHelper(system_state,
-                                             &uptime_since_last_storage,
-                                             &uptime_since_last)) {
-    metric = kMetricCheckTimeSinceLastCheckUptimeMinutes;
-    LOG(INFO) << "Sending " << utils::FormatTimeDelta(uptime_since_last)
-              << " for metric " << metric;
-    system_state->metrics_lib()->SendToUMA(
-        metric,
-        uptime_since_last.InMinutes(),
-        0,         // min: 0 min
-        30*24*60,  // max: 30 days
-        50);       // num_buckets
-  }
-}
-
-void ReportAbnormallyTerminatedUpdateAttemptMetrics(
-    SystemState *system_state) {
-
-  string metric = metrics::kMetricAttemptResult;
-  AttemptResult attempt_result = AttemptResult::kAbnormalTermination;
-
-  LOG(INFO) << "Uploading " << static_cast<int>(attempt_result)
-            << " for metric " <<  metric;
-  system_state->metrics_lib()->SendEnumToUMA(
-      metric,
-      static_cast<int>(attempt_result),
-      static_cast<int>(AttemptResult::kNumConstants));
-}
-
-void ReportUpdateAttemptMetrics(
-    SystemState *system_state,
-    int attempt_number,
-    PayloadType payload_type,
-    base::TimeDelta duration,
-    base::TimeDelta duration_uptime,
-    int64_t payload_size,
-    int64_t payload_bytes_downloaded,
-    int64_t payload_download_speed_bps,
-    DownloadSource download_source,
-    AttemptResult attempt_result,
-    ErrorCode internal_error_code,
-    DownloadErrorCode payload_download_error_code,
-    ConnectionType connection_type) {
-  string metric;
-
-  metric = metrics::kMetricAttemptNumber;
-  LOG(INFO) << "Uploading " << attempt_number << " for metric " <<  metric;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         attempt_number,
-                                         0,    // min: 0 attempts
-                                         49,   // max: 49 attempts
-                                         50);  // num_buckets
-
-  metric = metrics::kMetricAttemptPayloadType;
-  LOG(INFO) << "Uploading " << utils::ToString(payload_type)
-            << " for metric " <<  metric;
-  system_state->metrics_lib()->SendEnumToUMA(metric,
-                                             payload_type,
-                                             kNumPayloadTypes);
-
-  metric = metrics::kMetricAttemptDurationMinutes;
-  LOG(INFO) << "Uploading " << utils::FormatTimeDelta(duration)
-            << " for metric " <<  metric;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         duration.InMinutes(),
-                                         0,         // min: 0 min
-                                         10*24*60,  // max: 10 days
-                                         50);       // num_buckets
-
-  metric = metrics::kMetricAttemptDurationUptimeMinutes;
-  LOG(INFO) << "Uploading " << utils::FormatTimeDelta(duration_uptime)
-            << " for metric " <<  metric;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         duration_uptime.InMinutes(),
-                                         0,         // min: 0 min
-                                         10*24*60,  // max: 10 days
-                                         50);       // num_buckets
-
-  metric = metrics::kMetricAttemptPayloadSizeMiB;
-  int64_t payload_size_mib = payload_size / kNumBytesInOneMiB;
-  LOG(INFO) << "Uploading " << payload_size_mib << " for metric " <<  metric;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         payload_size_mib,
-                                         0,     // min: 0 MiB
-                                         1024,  // max: 1024 MiB = 1 GiB
-                                         50);   // num_buckets
-
-  metric = metrics::kMetricAttemptPayloadBytesDownloadedMiB;
-  int64_t payload_bytes_downloaded_mib =
-       payload_bytes_downloaded / kNumBytesInOneMiB;
-  LOG(INFO) << "Uploading " << payload_bytes_downloaded_mib
-            << " for metric " <<  metric;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         payload_bytes_downloaded_mib,
-                                         0,     // min: 0 MiB
-                                         1024,  // max: 1024 MiB = 1 GiB
-                                         50);   // num_buckets
-
-  metric = metrics::kMetricAttemptPayloadDownloadSpeedKBps;
-  int64_t payload_download_speed_kbps = payload_download_speed_bps / 1000;
-  LOG(INFO) << "Uploading " << payload_download_speed_kbps
-            << " for metric " <<  metric;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         payload_download_speed_kbps,
-                                         0,        // min: 0 kB/s
-                                         10*1000,  // max: 10000 kB/s = 10 MB/s
-                                         50);      // num_buckets
-
-  metric = metrics::kMetricAttemptDownloadSource;
-  LOG(INFO) << "Uploading " << download_source
-            << " for metric " <<  metric;
-  system_state->metrics_lib()->SendEnumToUMA(metric,
-                                             download_source,
-                                             kNumDownloadSources);
-
-  metric = metrics::kMetricAttemptResult;
-  LOG(INFO) << "Uploading " << static_cast<int>(attempt_result)
-            << " for metric " <<  metric;
-  system_state->metrics_lib()->SendEnumToUMA(
-      metric,
-      static_cast<int>(attempt_result),
-      static_cast<int>(AttemptResult::kNumConstants));
-
-  if (internal_error_code != ErrorCode::kSuccess) {
-    metric = metrics::kMetricAttemptInternalErrorCode;
-    LOG(INFO) << "Uploading " << internal_error_code
-              << " for metric " <<  metric;
-    system_state->metrics_lib()->SendEnumToUMA(
-        metric,
-        static_cast<int>(internal_error_code),
-        static_cast<int>(ErrorCode::kUmaReportedMax));
-  }
-
-  if (payload_download_error_code != DownloadErrorCode::kUnset) {
-    metric = metrics::kMetricAttemptDownloadErrorCode;
-    LOG(INFO) << "Uploading " << static_cast<int>(payload_download_error_code)
-              << " for metric " <<  metric << " (sparse)";
-    system_state->metrics_lib()->SendSparseToUMA(
-        metric,
-        static_cast<int>(payload_download_error_code));
-  }
-
-  base::TimeDelta time_since_last;
-  if (metrics_utils::WallclockDurationHelper(
-          system_state,
-          kPrefsMetricsAttemptLastReportingTime,
-          &time_since_last)) {
-    metric = kMetricAttemptTimeSinceLastAttemptMinutes;
-    LOG(INFO) << "Sending " << utils::FormatTimeDelta(time_since_last)
-              << " for metric " << metric;
-    system_state->metrics_lib()->SendToUMA(
-        metric,
-        time_since_last.InMinutes(),
-        0,         // min: 0 min
-        30*24*60,  // max: 30 days
-        50);       // num_buckets
-  }
-
-  static int64_t uptime_since_last_storage = 0;
-  base::TimeDelta uptime_since_last;
-  if (metrics_utils::MonotonicDurationHelper(system_state,
-                                             &uptime_since_last_storage,
-                                             &uptime_since_last)) {
-    metric = kMetricAttemptTimeSinceLastAttemptUptimeMinutes;
-    LOG(INFO) << "Sending " << utils::FormatTimeDelta(uptime_since_last)
-              << " for metric " << metric;
-    system_state->metrics_lib()->SendToUMA(
-        metric,
-        uptime_since_last.InMinutes(),
-        0,         // min: 0 min
-        30*24*60,  // max: 30 days
-        50);       // num_buckets
-  }
-
-  metric = metrics::kMetricAttemptConnectionType;
-  LOG(INFO) << "Uploading " << static_cast<int>(connection_type)
-            << " for metric " <<  metric;
-  system_state->metrics_lib()->SendEnumToUMA(
-      metric,
-      static_cast<int>(connection_type),
-      static_cast<int>(ConnectionType::kNumConstants));
-}
-
-
-void ReportSuccessfulUpdateMetrics(
-         SystemState *system_state,
-         int attempt_count,
-         int updates_abandoned_count,
-         PayloadType payload_type,
-         int64_t payload_size,
-         int64_t num_bytes_downloaded[kNumDownloadSources],
-         int download_overhead_percentage,
-         base::TimeDelta total_duration,
-         int reboot_count,
-         int url_switch_count) {
-  string metric;
-  int64_t mbs;
-
-  metric = kMetricSuccessfulUpdatePayloadSizeMiB;
-  mbs = payload_size / kNumBytesInOneMiB;
-  LOG(INFO) << "Uploading " << mbs << " (MiBs) for metric " << metric;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         mbs,
-                                         0,     // min: 0 MiB
-                                         1024,  // max: 1024 MiB = 1 GiB
-                                         50);   // num_buckets
-
-  int64_t total_bytes = 0;
-  int download_sources_used = 0;
-  for (int i = 0; i < kNumDownloadSources + 1; i++) {
-    DownloadSource source = static_cast<DownloadSource>(i);
-
-    // Only consider this download source (and send byte counts) as
-    // having been used if we downloaded a non-trivial amount of bytes
-    // (e.g. at least 1 MiB) that contributed to the
-    // update. Otherwise we're going to end up with a lot of zero-byte
-    // events in the histogram.
-
-    metric = metrics::kMetricSuccessfulUpdateBytesDownloadedMiB;
-    if (i < kNumDownloadSources) {
-      metric += utils::ToString(source);
-      mbs = num_bytes_downloaded[i] / kNumBytesInOneMiB;
-      total_bytes += num_bytes_downloaded[i];
-      if (mbs > 0)
-        download_sources_used |= (1 << i);
-    } else {
-      mbs = total_bytes / kNumBytesInOneMiB;
-    }
-
-    if (mbs > 0) {
-      LOG(INFO) << "Uploading " << mbs << " (MiBs) for metric " << metric;
-      system_state->metrics_lib()->SendToUMA(metric,
-                                             mbs,
-                                             0,     // min: 0 MiB
-                                             1024,  // max: 1024 MiB = 1 GiB
-                                             50);   // num_buckets
-    }
-  }
-
-  metric = metrics::kMetricSuccessfulUpdateDownloadSourcesUsed;
-  LOG(INFO) << "Uploading 0x" << std::hex << download_sources_used
-            << " (bit flags) for metric " << metric;
-  system_state->metrics_lib()->SendToUMA(
-      metric,
-      download_sources_used,
-      0,                               // min
-      (1 << kNumDownloadSources) - 1,  // max
-      1 << kNumDownloadSources);       // num_buckets
-
-  metric = metrics::kMetricSuccessfulUpdateDownloadOverheadPercentage;
-  LOG(INFO) << "Uploading " << download_overhead_percentage
-            << "% for metric " << metric;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         download_overhead_percentage,
-                                         0,     // min: 0% overhead
-                                         1000,  // max: 1000% overhead
-                                         50);   // num_buckets
-
-  metric = metrics::kMetricSuccessfulUpdateUrlSwitchCount;
-  LOG(INFO) << "Uploading " << url_switch_count
-            << " (count) for metric " <<  metric;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         url_switch_count,
-                                         0,    // min: 0 URL switches
-                                         49,   // max: 49 URL switches
-                                         50);  // num_buckets
-
-  metric = metrics::kMetricSuccessfulUpdateTotalDurationMinutes;
-  LOG(INFO) << "Uploading " << utils::FormatTimeDelta(total_duration)
-            << " for metric " <<  metric;
-  system_state->metrics_lib()->SendToUMA(
-       metric,
-       static_cast<int>(total_duration.InMinutes()),
-       0,          // min: 0 min
-       365*24*60,  // max: 365 days ~= 1 year
-       50);        // num_buckets
-
-  metric = metrics::kMetricSuccessfulUpdateRebootCount;
-  LOG(INFO) << "Uploading reboot count of " << reboot_count << " for metric "
-            <<  metric;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         reboot_count,
-                                         0,    // min: 0 reboots
-                                         49,   // max: 49 reboots
-                                         50);  // num_buckets
-
-  metric = metrics::kMetricSuccessfulUpdatePayloadType;
-  system_state->metrics_lib()->SendEnumToUMA(metric,
-                                             payload_type,
-                                             kNumPayloadTypes);
-  LOG(INFO) << "Uploading " << utils::ToString(payload_type)
-            << " for metric " <<  metric;
-
-  metric = metrics::kMetricSuccessfulUpdateAttemptCount;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         attempt_count,
-                                         1,    // min: 1 attempt
-                                         50,   // max: 50 attempts
-                                         50);  // num_buckets
-  LOG(INFO) << "Uploading " << attempt_count
-            << " for metric " <<  metric;
-
-  metric = metrics::kMetricSuccessfulUpdateUpdatesAbandonedCount;
-  LOG(INFO) << "Uploading " << updates_abandoned_count
-            << " (count) for metric " <<  metric;
-  system_state->metrics_lib()->SendToUMA(metric,
-                                         updates_abandoned_count,
-                                         0,    // min: 0 counts
-                                         49,   // max: 49 counts
-                                         50);  // num_buckets
-}
-
-void ReportRollbackMetrics(SystemState *system_state,
-                           RollbackResult result) {
-  string metric;
-  int value;
-
-  metric = metrics::kMetricRollbackResult;
-  value = static_cast<int>(result);
-  LOG(INFO) << "Sending " << value << " for metric " << metric << " (enum)";
-  system_state->metrics_lib()->SendEnumToUMA(
-      metric,
-      value,
-      static_cast<int>(metrics::RollbackResult::kNumConstants));
-}
-
-void ReportCertificateCheckMetrics(SystemState* system_state,
-                                   ServerToCheck server_to_check,
-                                   CertificateCheckResult result) {
-  string metric;
-  switch (server_to_check) {
-    case ServerToCheck::kUpdate:
-      metric = kMetricCertificateCheckUpdateCheck;
-      break;
-    case ServerToCheck::kDownload:
-      metric = kMetricCertificateCheckDownload;
-      break;
-    case ServerToCheck::kNone:
-      return;
-  }
-  LOG(INFO) << "Uploading " << static_cast<int>(result) << " for metric "
-            << metric;
-  system_state->metrics_lib()->SendEnumToUMA(
-      metric, static_cast<int>(result),
-      static_cast<int>(CertificateCheckResult::kNumConstants));
-}
-
-}  // namespace metrics
-
-}  // namespace chromeos_update_engine
diff --git a/metrics.h b/metrics.h
deleted file mode 100644
index 7c369ee..0000000
--- a/metrics.h
+++ /dev/null
@@ -1,321 +0,0 @@
-//
-// Copyright (C) 2014 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-
-#ifndef UPDATE_ENGINE_METRICS_H_
-#define UPDATE_ENGINE_METRICS_H_
-
-#include <base/time/time.h>
-
-#include "update_engine/certificate_checker.h"
-#include "update_engine/common/constants.h"
-#include "update_engine/common/error_code.h"
-
-namespace chromeos_update_engine {
-
-class SystemState;
-
-namespace metrics {
-
-// UpdateEngine.Daily.* metrics.
-extern const char kMetricDailyOSAgeDays[];
-
-// UpdateEngine.Check.* metrics.
-extern const char kMetricCheckDownloadErrorCode[];
-extern const char kMetricCheckReaction[];
-extern const char kMetricCheckResult[];
-extern const char kMetricCheckTimeSinceLastCheckMinutes[];
-extern const char kMetricCheckTimeSinceLastCheckUptimeMinutes[];
-
-// UpdateEngine.Attempt.* metrics.
-extern const char kMetricAttemptNumber[];
-extern const char kMetricAttemptPayloadType[];
-extern const char kMetricAttemptPayloadSizeMiB[];
-extern const char kMetricAttemptConnectionType[];
-extern const char kMetricAttemptDurationMinutes[];
-extern const char kMetricAttemptDurationUptimeMinutes[];
-extern const char kMetricAttemptTimeSinceLastAttemptSeconds[];
-extern const char kMetricAttemptTimeSinceLastAttemptUptimeSeconds[];
-extern const char kMetricAttemptPayloadBytesDownloaded[];
-extern const char kMetricAttemptPayloadDownloadSpeedKBps[];
-extern const char kMetricAttemptDownloadSource[];
-extern const char kMetricAttemptResult[];
-extern const char kMetricAttemptInternalErrorCode[];
-extern const char kMetricAttemptDownloadErrorCode[];
-
-// UpdateEngine.SuccessfulUpdate.* metrics.
-extern const char kMetricSuccessfulUpdateAttemptCount[];
-extern const char kMetricSuccessfulUpdateBytesDownloadedMiB[];
-extern const char kMetricSuccessfulUpdateDownloadOverheadPercentage[];
-extern const char kMetricSuccessfulUpdateDownloadSourcesUsed[];
-extern const char kMetricSuccessfulUpdatePayloadType[];
-extern const char kMetricSuccessfulUpdatePayloadSizeMiB[];
-extern const char kMetricSuccessfulUpdateTotalDurationMinutes[];
-extern const char kMetricSuccessfulUpdateRebootCount[];
-extern const char kMetricSuccessfulUpdateUpdatesAbandonedCount[];
-extern const char kMetricSuccessfulUpdateUrlSwitchCount[];
-
-// UpdateEngine.Rollback.* metric.
-extern const char kMetricRollbackResult[];
-
-// UpdateEngine.* metrics.
-extern const char kMetricFailedUpdateCount[];
-extern const char kMetricInstallDateProvisioningSource[];
-extern const char kMetricTimeToRebootMinutes[];
-
-// The possible outcomes when checking for updates.
-//
-// This is used in the UpdateEngine.Check.Result histogram.
-enum class CheckResult {
-  kUpdateAvailable,    // Response indicates an update is available.
-  kNoUpdateAvailable,  // Response indicates no updates are available.
-  kDownloadError,      // Error downloading response from Omaha.
-  kParsingError,       // Error parsing response.
-  kRebootPending,      // No update check was performed a reboot is pending.
-
-  kNumConstants,
-  kUnset = -1
-};
-
-// Possible ways a device can react to a new update being available.
-//
-// This is used in the UpdateEngine.Check.Reaction histogram.
-enum class CheckReaction {
-  kUpdating,    // Device proceeds to download and apply update.
-  kIgnored  ,   // Device-policy dictates ignoring the update.
-  kDeferring,   // Device-policy dictates waiting.
-  kBackingOff,  // Previous errors dictates waiting.
-
-  kNumConstants,
-  kUnset = -1
-};
-
-// The possible ways that downloading from a HTTP or HTTPS server can fail.
-//
-// This is used in the UpdateEngine.Check.DownloadErrorCode and
-// UpdateEngine.Attempt.DownloadErrorCode histograms.
-enum class DownloadErrorCode {
-  // Errors that can happen in the field. See http://crbug.com/355745
-  // for how we plan to add more detail in the future.
-  kDownloadError = 0,  // Error downloading data from server.
-
-  // IMPORTANT: When adding a new error code, add at the bottom of the
-  // above block and before the kInputMalformed field. This
-  // is to ensure that error codes are not reordered.
-
-  // This error code is used to convey that malformed input was given
-  // to the utils::GetDownloadErrorCode() function. This should never
-  // happen but if it does it's because of an internal update_engine
-  // error and we're interested in knowing this.
-  kInputMalformed = 100,
-
-  // Bucket for capturing HTTP status codes not in the 200-599
-  // range. This should never happen in practice but if it does we
-  // want to know.
-  kHttpStatusOther = 101,
-
-  // Above 200 and below 600, the value is the HTTP status code.
-  kHttpStatus200 = 200,
-
-  kNumConstants = 600,
-
-  kUnset = -1
-};
-
-// Possible ways an update attempt can end.
-//
-// This is used in the UpdateEngine.Attempt.Result histogram.
-enum class AttemptResult {
-  kUpdateSucceeded,             // The update succeeded.
-  kInternalError,               // An internal error occurred.
-  kPayloadDownloadError,        // Failure while downloading payload.
-  kMetadataMalformed,           // Metadata was malformed.
-  kOperationMalformed,          // An operation was malformed.
-  kOperationExecutionError,     // An operation failed to execute.
-  kMetadataVerificationFailed,  // Metadata verification failed.
-  kPayloadVerificationFailed,   // Payload verification failed.
-  kVerificationFailed,          // Root or Kernel partition verification failed.
-  kPostInstallFailed,           // The postinstall step failed.
-  kAbnormalTermination,         // The attempt ended abnormally.
-  kUpdateCanceled,              // Update canceled by the user.
-
-  kNumConstants,
-
-  kUnset = -1
-};
-
-// Possible ways the device is connected to the Internet.
-//
-// This is used in the UpdateEngine.Attempt.ConnectionType histogram.
-enum class ConnectionType {
-  kUnknown,           // Unknown.
-  kEthernet,          // Ethernet.
-  kWifi,              // Wireless.
-  kWimax,             // WiMax.
-  kBluetooth,         // Bluetooth.
-  kCellular,          // Cellular.
-  kTetheredEthernet,  // Tethered (Ethernet).
-  kTetheredWifi,      // Tethered (Wifi).
-
-  kNumConstants,
-  kUnset = -1
-};
-
-// Possible ways a rollback can end.
-//
-// This is used in the UpdateEngine.Rollback histogram.
-enum class RollbackResult {
-  kFailed,
-  kSuccess,
-
-  kNumConstants
-};
-
-// Helper function to report metrics related to rollback. The
-// following metrics are reported:
-//
-//  |kMetricRollbackResult|
-void ReportRollbackMetrics(SystemState *system_state,
-                           RollbackResult result);
-
-// Helper function to report metrics reported once a day. The
-// following metrics are reported:
-//
-//  |kMetricDailyOSAgeDays|
-void ReportDailyMetrics(SystemState *system_state,
-                        base::TimeDelta os_age);
-
-// Helper function to report metrics after completing an update check
-// with the ChromeOS update server ("Omaha"). The following metrics
-// are reported:
-//
-//  |kMetricCheckResult|
-//  |kMetricCheckReaction|
-//  |kMetricCheckDownloadErrorCode|
-//  |kMetricCheckTimeSinceLastCheckMinutes|
-//  |kMetricCheckTimeSinceLastCheckUptimeMinutes|
-//
-// The |kMetricCheckResult| metric will only be reported if |result|
-// is not |kUnset|.
-//
-// The |kMetricCheckReaction| metric will only be reported if
-// |reaction| is not |kUnset|.
-//
-// The |kMetricCheckDownloadErrorCode| will only be reported if
-// |download_error_code| is not |kUnset|.
-//
-// The values for the |kMetricCheckTimeSinceLastCheckMinutes| and
-// |kMetricCheckTimeSinceLastCheckUptimeMinutes| metrics are
-// automatically reported and calculated by maintaining persistent
-// and process-local state variables.
-void ReportUpdateCheckMetrics(SystemState *system_state,
-                              CheckResult result,
-                              CheckReaction reaction,
-                              DownloadErrorCode download_error_code);
-
-
-// Helper function to report metrics after the completion of each
-// update attempt. The following metrics are reported:
-//
-//  |kMetricAttemptNumber|
-//  |kMetricAttemptPayloadType|
-//  |kMetricAttemptPayloadSizeMiB|
-//  |kMetricAttemptDurationSeconds|
-//  |kMetricAttemptDurationUptimeSeconds|
-//  |kMetricAttemptTimeSinceLastAttemptMinutes|
-//  |kMetricAttemptTimeSinceLastAttemptUptimeMinutes|
-//  |kMetricAttemptPayloadBytesDownloadedMiB|
-//  |kMetricAttemptPayloadDownloadSpeedKBps|
-//  |kMetricAttemptDownloadSource|
-//  |kMetricAttemptResult|
-//  |kMetricAttemptInternalErrorCode|
-//  |kMetricAttemptDownloadErrorCode|
-//
-// The |kMetricAttemptInternalErrorCode| metric will only be reported
-// if |internal_error_code| is not |kErrorSuccess|.
-//
-// The |kMetricAttemptDownloadErrorCode| metric will only be
-// reported if |payload_download_error_code| is not |kUnset|.
-//
-// The values for the |kMetricAttemptTimeSinceLastAttemptMinutes| and
-// |kMetricAttemptTimeSinceLastAttemptUptimeMinutes| metrics are
-// automatically calculated and reported by maintaining persistent and
-// process-local state variables.
-void ReportUpdateAttemptMetrics(
-    SystemState *system_state,
-    int attempt_number,
-    PayloadType payload_type,
-    base::TimeDelta duration,
-    base::TimeDelta duration_uptime,
-    int64_t payload_size,
-    int64_t payload_bytes_downloaded,
-    int64_t payload_download_speed_bps,
-    DownloadSource download_source,
-    AttemptResult attempt_result,
-    ErrorCode internal_error_code,
-    DownloadErrorCode payload_download_error_code,
-    ConnectionType connection_type);
-
-// Reports the |kAbnormalTermination| for the |kMetricAttemptResult|
-// metric. No other metrics in the UpdateEngine.Attempt.* namespace
-// will be reported.
-void ReportAbnormallyTerminatedUpdateAttemptMetrics(SystemState *system_state);
-
-// Helper function to report the after the completion of a successful
-// update attempt. The following metrics are reported:
-//
-//  |kMetricSuccessfulUpdateAttemptCount|
-//  |kMetricSuccessfulUpdateUpdatesAbandonedCount|
-//  |kMetricSuccessfulUpdatePayloadType|
-//  |kMetricSuccessfulUpdatePayloadSizeMiB|
-//  |kMetricSuccessfulUpdateBytesDownloadedMiBHttpsServer|
-//  |kMetricSuccessfulUpdateBytesDownloadedMiBHttpServer|
-//  |kMetricSuccessfulUpdateBytesDownloadedMiBHttpPeer|
-//  |kMetricSuccessfulUpdateBytesDownloadedMiB|
-//  |kMetricSuccessfulUpdateDownloadSourcesUsed|
-//  |kMetricSuccessfulUpdateDownloadOverheadPercentage|
-//  |kMetricSuccessfulUpdateTotalDurationMinutes|
-//  |kMetricSuccessfulUpdateRebootCount|
-//  |kMetricSuccessfulUpdateUrlSwitchCount|
-//
-// The values for the |kMetricSuccessfulUpdateDownloadSourcesUsed| are
-// |kMetricSuccessfulUpdateBytesDownloadedMiB| metrics automatically
-// calculated from examining the |num_bytes_downloaded| array.
-void ReportSuccessfulUpdateMetrics(
-    SystemState *system_state,
-    int attempt_count,
-    int updates_abandoned_count,
-    PayloadType payload_type,
-    int64_t payload_size,
-    int64_t num_bytes_downloaded[kNumDownloadSources],
-    int download_overhead_percentage,
-    base::TimeDelta total_duration,
-    int reboot_count,
-    int url_switch_count);
-
-// Helper function to report the after the completion of a SSL certificate
-// check. One of the following metrics is reported:
-//
-//  |kMetricCertificateCheckUpdateCheck|
-//  |kMetricCertificateCheckDownload|
-void ReportCertificateCheckMetrics(SystemState* system_state,
-                                   ServerToCheck server_to_check,
-                                   CertificateCheckResult result);
-
-}  // namespace metrics
-
-}  // namespace chromeos_update_engine
-
-#endif  // UPDATE_ENGINE_METRICS_H_
diff --git a/metrics_constants.h b/metrics_constants.h
new file mode 100644
index 0000000..abec2ad
--- /dev/null
+++ b/metrics_constants.h
@@ -0,0 +1,137 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_METRICS_CONSTANTS_H_
+#define UPDATE_ENGINE_METRICS_CONSTANTS_H_
+
+namespace chromeos_update_engine {
+
+namespace metrics {
+// The possible outcomes when checking for updates.
+//
+// This is used in the UpdateEngine.Check.Result histogram.
+enum class CheckResult {
+  kUpdateAvailable,    // Response indicates an update is available.
+  kNoUpdateAvailable,  // Response indicates no updates are available.
+  kDownloadError,      // Error downloading response from Omaha.
+  kParsingError,       // Error parsing response.
+  kRebootPending,      // No update check was performed a reboot is pending.
+
+  kNumConstants,
+  kUnset = -1
+};
+
+// Possible ways a device can react to a new update being available.
+//
+// This is used in the UpdateEngine.Check.Reaction histogram.
+enum class CheckReaction {
+  kUpdating,    // Device proceeds to download and apply update.
+  kIgnored,     // Device-policy dictates ignoring the update.
+  kDeferring,   // Device-policy dictates waiting.
+  kBackingOff,  // Previous errors dictates waiting.
+
+  kNumConstants,
+  kUnset = -1
+};
+
+// The possible ways that downloading from a HTTP or HTTPS server can fail.
+//
+// This is used in the UpdateEngine.Check.DownloadErrorCode and
+// UpdateEngine.Attempt.DownloadErrorCode histograms.
+enum class DownloadErrorCode {
+  // Errors that can happen in the field. See http://crbug.com/355745
+  // for how we plan to add more detail in the future.
+  kDownloadError = 0,  // Error downloading data from server.
+
+  // IMPORTANT: When adding a new error code, add at the bottom of the
+  // above block and before the kInputMalformed field. This
+  // is to ensure that error codes are not reordered.
+
+  // This error code is used to convey that malformed input was given
+  // to the utils::GetDownloadErrorCode() function. This should never
+  // happen but if it does it's because of an internal update_engine
+  // error and we're interested in knowing this.
+  kInputMalformed = 100,
+
+  // Bucket for capturing HTTP status codes not in the 200-599
+  // range. This should never happen in practice but if it does we
+  // want to know.
+  kHttpStatusOther = 101,
+
+  // Above 200 and below 600, the value is the HTTP status code.
+  kHttpStatus200 = 200,
+
+  kNumConstants = 600,
+
+  kUnset = -1
+};
+
+// Possible ways an update attempt can end.
+//
+// This is used in the UpdateEngine.Attempt.Result histogram.
+enum class AttemptResult {
+  kUpdateSucceeded,             // The update succeeded.
+  kInternalError,               // An internal error occurred.
+  kPayloadDownloadError,        // Failure while downloading payload.
+  kMetadataMalformed,           // Metadata was malformed.
+  kOperationMalformed,          // An operation was malformed.
+  kOperationExecutionError,     // An operation failed to execute.
+  kMetadataVerificationFailed,  // Metadata verification failed.
+  kPayloadVerificationFailed,   // Payload verification failed.
+  kVerificationFailed,          // Root or Kernel partition verification failed.
+  kPostInstallFailed,           // The postinstall step failed.
+  kAbnormalTermination,         // The attempt ended abnormally.
+  kUpdateCanceled,              // Update canceled by the user.
+  kUpdateSucceededNotActive,    // Update succeeded but the new slot is not
+                                // active.
+
+  kNumConstants,
+
+  kUnset = -1
+};
+
+// Possible ways the device is connected to the Internet.
+//
+// This is used in the UpdateEngine.Attempt.ConnectionType histogram.
+enum class ConnectionType {
+  kUnknown,           // Unknown.
+  kEthernet,          // Ethernet.
+  kWifi,              // Wireless.
+  kWimax,             // WiMax.
+  kBluetooth,         // Bluetooth.
+  kCellular,          // Cellular.
+  kTetheredEthernet,  // Tethered (Ethernet).
+  kTetheredWifi,      // Tethered (Wifi).
+
+  kNumConstants,
+  kUnset = -1
+};
+
+// Possible ways a rollback can end.
+//
+// This is used in the UpdateEngine.Rollback histogram.
+enum class RollbackResult {
+  kFailed,
+  kSuccess,
+
+  kNumConstants
+};
+
+}  // namespace metrics
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_METRICS_CONSTANTS_H_
diff --git a/metrics_reporter_android.cc b/metrics_reporter_android.cc
new file mode 100644
index 0000000..3cb356f
--- /dev/null
+++ b/metrics_reporter_android.cc
@@ -0,0 +1,158 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/metrics_reporter_android.h"
+
+#include <memory>
+#include <string>
+
+#include <metricslogger/metrics_logger.h>
+
+#include "update_engine/common/constants.h"
+
+namespace {
+void LogHistogram(const std::string& metrics, int value) {
+  android::metricslogger::LogHistogram(metrics, value);
+  LOG(INFO) << "uploading " << value << " to histogram for metric " << metrics;
+}
+}  // namespace
+
+namespace chromeos_update_engine {
+
+namespace metrics {
+
+// The histograms are defined in:
+// depot/google3/analysis/uma/configs/clearcut/TRON/histograms.xml
+constexpr char kMetricsUpdateEngineAttemptNumber[] =
+    "ota_update_engine_attempt_number";
+constexpr char kMetricsUpdateEngineAttemptResult[] =
+    "ota_update_engine_attempt_result";
+constexpr char kMetricsUpdateEngineAttemptDurationInMinutes[] =
+    "ota_update_engine_attempt_duration_boottime_in_minutes";
+constexpr char kMetricsUpdateEngineAttemptDurationUptimeInMinutes[] =
+    "ota_update_engine_attempt_duration_monotonic_in_minutes";
+constexpr char kMetricsUpdateEngineAttemptErrorCode[] =
+    "ota_update_engine_attempt_error_code";
+constexpr char kMetricsUpdateEngineAttemptPayloadSizeMiB[] =
+    "ota_update_engine_attempt_payload_size_mib";
+constexpr char kMetricsUpdateEngineAttemptPayloadType[] =
+    "ota_update_engine_attempt_payload_type";
+constexpr char kMetricsUpdateEngineAttemptCurrentBytesDownloadedMiB[] =
+    "ota_update_engine_attempt_current_bytes_downloaded_mib";
+
+constexpr char kMetricsUpdateEngineSuccessfulUpdateAttemptCount[] =
+    "ota_update_engine_successful_update_attempt_count";
+constexpr char kMetricsUpdateEngineSuccessfulUpdateTotalDurationInMinutes[] =
+    "ota_update_engine_successful_update_total_duration_in_minutes";
+constexpr char kMetricsUpdateEngineSuccessfulUpdatePayloadSizeMiB[] =
+    "ota_update_engine_successful_update_payload_size_mib";
+constexpr char kMetricsUpdateEngineSuccessfulUpdatePayloadType[] =
+    "ota_update_engine_successful_update_payload_type";
+constexpr char kMetricsUpdateEngineSuccessfulUpdateRebootCount[] =
+    "ota_update_engine_successful_update_reboot_count";
+constexpr char kMetricsUpdateEngineSuccessfulUpdateTotalBytesDownloadedMiB[] =
+    "ota_update_engine_successful_update_total_bytes_downloaded_mib";
+constexpr char
+    kMetricsUpdateEngineSuccessfulUpdateDownloadOverheadPercentage[] =
+        "ota_update_engine_successful_update_download_overhead_percentage";
+
+std::unique_ptr<MetricsReporterInterface> CreateMetricsReporter() {
+  return std::make_unique<MetricsReporterAndroid>();
+}
+
+}  // namespace metrics
+
+void MetricsReporterAndroid::ReportUpdateAttemptMetrics(
+    SystemState* /* system_state */,
+    int attempt_number,
+    PayloadType payload_type,
+    base::TimeDelta duration,
+    base::TimeDelta duration_uptime,
+    int64_t payload_size,
+    metrics::AttemptResult attempt_result,
+    ErrorCode error_code) {
+  LogHistogram(metrics::kMetricsUpdateEngineAttemptNumber, attempt_number);
+  LogHistogram(metrics::kMetricsUpdateEngineAttemptPayloadType,
+               static_cast<int>(payload_type));
+  LogHistogram(metrics::kMetricsUpdateEngineAttemptDurationInMinutes,
+               duration.InMinutes());
+  LogHistogram(metrics::kMetricsUpdateEngineAttemptDurationUptimeInMinutes,
+               duration_uptime.InMinutes());
+
+  int64_t payload_size_mib = payload_size / kNumBytesInOneMiB;
+  LogHistogram(metrics::kMetricsUpdateEngineAttemptPayloadSizeMiB,
+               payload_size_mib);
+
+  LogHistogram(metrics::kMetricsUpdateEngineAttemptResult,
+               static_cast<int>(attempt_result));
+  LogHistogram(metrics::kMetricsUpdateEngineAttemptErrorCode,
+               static_cast<int>(error_code));
+}
+
+void MetricsReporterAndroid::ReportUpdateAttemptDownloadMetrics(
+    int64_t payload_bytes_downloaded,
+    int64_t /* payload_download_speed_bps */,
+    DownloadSource /* download_source */,
+    metrics::DownloadErrorCode /* payload_download_error_code */,
+    metrics::ConnectionType /* connection_type */) {
+  LogHistogram(metrics::kMetricsUpdateEngineAttemptCurrentBytesDownloadedMiB,
+               payload_bytes_downloaded);
+}
+
+void MetricsReporterAndroid::ReportSuccessfulUpdateMetrics(
+    int attempt_count,
+    int /* updates_abandoned_count */,
+    PayloadType payload_type,
+    int64_t payload_size,
+    int64_t num_bytes_downloaded[kNumDownloadSources],
+    int download_overhead_percentage,
+    base::TimeDelta total_duration,
+    int reboot_count,
+    int /* url_switch_count */) {
+  LogHistogram(metrics::kMetricsUpdateEngineSuccessfulUpdateAttemptCount,
+               attempt_count);
+  LogHistogram(metrics::kMetricsUpdateEngineSuccessfulUpdatePayloadType,
+               static_cast<int>(payload_type));
+
+  int64_t payload_size_mib = payload_size / kNumBytesInOneMiB;
+  LogHistogram(metrics::kMetricsUpdateEngineSuccessfulUpdatePayloadSizeMiB,
+               payload_size_mib);
+
+  int64_t total_bytes_downloaded = 0;
+  for (size_t i = 0; i < kNumDownloadSources; i++) {
+    total_bytes_downloaded += num_bytes_downloaded[i] / kNumBytesInOneMiB;
+  }
+  LogHistogram(
+      metrics::kMetricsUpdateEngineSuccessfulUpdateTotalBytesDownloadedMiB,
+      total_bytes_downloaded);
+  LogHistogram(
+      metrics::kMetricsUpdateEngineSuccessfulUpdateDownloadOverheadPercentage,
+      download_overhead_percentage);
+
+  LogHistogram(
+      metrics::kMetricsUpdateEngineSuccessfulUpdateTotalDurationInMinutes,
+      total_duration.InMinutes());
+  LogHistogram(metrics::kMetricsUpdateEngineSuccessfulUpdateRebootCount,
+               reboot_count);
+}
+
+void MetricsReporterAndroid::ReportAbnormallyTerminatedUpdateAttemptMetrics() {
+  int attempt_result =
+      static_cast<int>(metrics::AttemptResult::kAbnormalTermination);
+  LogHistogram(metrics::kMetricsUpdateEngineAttemptResult, attempt_result);
+}
+
+};  // namespace chromeos_update_engine
diff --git a/metrics_reporter_android.h b/metrics_reporter_android.h
new file mode 100644
index 0000000..ee94e43
--- /dev/null
+++ b/metrics_reporter_android.h
@@ -0,0 +1,88 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_METRICS_REPORTER_ANDROID_H_
+#define UPDATE_ENGINE_METRICS_REPORTER_ANDROID_H_
+
+#include "update_engine/common/error_code.h"
+#include "update_engine/metrics_constants.h"
+#include "update_engine/metrics_reporter_interface.h"
+
+namespace chromeos_update_engine {
+
+class MetricsReporterAndroid : public MetricsReporterInterface {
+ public:
+  MetricsReporterAndroid() = default;
+
+  ~MetricsReporterAndroid() override = default;
+
+  void Initialize() override {}
+
+  void ReportRollbackMetrics(metrics::RollbackResult result) override {}
+
+  void ReportDailyMetrics(base::TimeDelta os_age) override {}
+
+  void ReportUpdateCheckMetrics(
+      SystemState* system_state,
+      metrics::CheckResult result,
+      metrics::CheckReaction reaction,
+      metrics::DownloadErrorCode download_error_code) override {}
+
+  void ReportUpdateAttemptMetrics(SystemState* system_state,
+                                  int attempt_number,
+                                  PayloadType payload_type,
+                                  base::TimeDelta duration,
+                                  base::TimeDelta duration_uptime,
+                                  int64_t payload_size,
+                                  metrics::AttemptResult attempt_result,
+                                  ErrorCode internal_error_code) override;
+
+  void ReportUpdateAttemptDownloadMetrics(
+      int64_t payload_bytes_downloaded,
+      int64_t payload_download_speed_bps,
+      DownloadSource download_source,
+      metrics::DownloadErrorCode payload_download_error_code,
+      metrics::ConnectionType connection_type) override;
+
+  void ReportAbnormallyTerminatedUpdateAttemptMetrics() override;
+
+  void ReportSuccessfulUpdateMetrics(
+      int attempt_count,
+      int updates_abandoned_count,
+      PayloadType payload_type,
+      int64_t payload_size,
+      int64_t num_bytes_downloaded[kNumDownloadSources],
+      int download_overhead_percentage,
+      base::TimeDelta total_duration,
+      int reboot_count,
+      int url_switch_count) override;
+
+  void ReportCertificateCheckMetrics(ServerToCheck server_to_check,
+                                     CertificateCheckResult result) override {}
+
+  void ReportFailedUpdateCount(int target_attempt) override {}
+
+  void ReportTimeToReboot(int time_to_reboot_minutes) override {}
+
+  void ReportInstallDateProvisioningSource(int source, int max) override {}
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(MetricsReporterAndroid);
+};
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_METRICS_REPORTER_ANDROID_H_
diff --git a/metrics_reporter_interface.h b/metrics_reporter_interface.h
new file mode 100644
index 0000000..2c7ce5b
--- /dev/null
+++ b/metrics_reporter_interface.h
@@ -0,0 +1,200 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_METRICS_REPORTER_INTERFACE_H_
+#define UPDATE_ENGINE_METRICS_REPORTER_INTERFACE_H_
+
+#include <memory>
+
+#include <base/time/time.h>
+
+#include "update_engine/common/constants.h"
+#include "update_engine/common/error_code.h"
+#include "update_engine/metrics_constants.h"
+#include "update_engine/system_state.h"
+
+namespace chromeos_update_engine {
+
+enum class ServerToCheck;
+enum class CertificateCheckResult;
+
+namespace metrics {
+
+std::unique_ptr<MetricsReporterInterface> CreateMetricsReporter();
+
+}  // namespace metrics
+
+class MetricsReporterInterface {
+ public:
+  virtual ~MetricsReporterInterface() = default;
+
+  virtual void Initialize() = 0;
+
+  // Helper function to report metrics related to rollback. The
+  // following metrics are reported:
+  //
+  //  |kMetricRollbackResult|
+  virtual void ReportRollbackMetrics(metrics::RollbackResult result) = 0;
+
+  // Helper function to report metrics reported once a day. The
+  // following metrics are reported:
+  //
+  //  |kMetricDailyOSAgeDays|
+  virtual void ReportDailyMetrics(base::TimeDelta os_age) = 0;
+
+  // Helper function to report metrics after completing an update check
+  // with the ChromeOS update server ("Omaha"). The following metrics
+  // are reported:
+  //
+  //  |kMetricCheckResult|
+  //  |kMetricCheckReaction|
+  //  |kMetricCheckDownloadErrorCode|
+  //  |kMetricCheckTimeSinceLastCheckMinutes|
+  //  |kMetricCheckTimeSinceLastCheckUptimeMinutes|
+  //
+  // The |kMetricCheckResult| metric will only be reported if |result|
+  // is not |kUnset|.
+  //
+  // The |kMetricCheckReaction| metric will only be reported if
+  // |reaction| is not |kUnset|.
+  //
+  // The |kMetricCheckDownloadErrorCode| will only be reported if
+  // |download_error_code| is not |kUnset|.
+  //
+  // The values for the |kMetricCheckTimeSinceLastCheckMinutes| and
+  // |kMetricCheckTimeSinceLastCheckUptimeMinutes| metrics are
+  // automatically reported and calculated by maintaining persistent
+  // and process-local state variables.
+  virtual void ReportUpdateCheckMetrics(
+      SystemState* system_state,
+      metrics::CheckResult result,
+      metrics::CheckReaction reaction,
+      metrics::DownloadErrorCode download_error_code) = 0;
+
+  // Helper function to report metrics after the completion of each
+  // update attempt. The following metrics are reported:
+  //
+  //  |kMetricAttemptNumber|
+  //  |kMetricAttemptPayloadType|
+  //  |kMetricAttemptPayloadSizeMiB|
+  //  |kMetricAttemptDurationMinutes|
+  //  |kMetricAttemptDurationUptimeMinutes|
+  //  |kMetricAttemptTimeSinceLastAttemptMinutes|
+  //  |kMetricAttemptTimeSinceLastAttemptUptimeMinutes|
+  //  |kMetricAttemptResult|
+  //  |kMetricAttemptInternalErrorCode|
+  //
+  // The |kMetricAttemptInternalErrorCode| metric will only be reported
+  // if |internal_error_code| is not |kErrorSuccess|.
+  //
+  // The |kMetricAttemptDownloadErrorCode| metric will only be
+  // reported if |payload_download_error_code| is not |kUnset|.
+  //
+  // The values for the |kMetricAttemptTimeSinceLastAttemptMinutes| and
+  // |kMetricAttemptTimeSinceLastAttemptUptimeMinutes| metrics are
+  // automatically calculated and reported by maintaining persistent and
+  // process-local state variables.
+  virtual void ReportUpdateAttemptMetrics(SystemState* system_state,
+                                          int attempt_number,
+                                          PayloadType payload_type,
+                                          base::TimeDelta duration,
+                                          base::TimeDelta duration_uptime,
+                                          int64_t payload_size,
+                                          metrics::AttemptResult attempt_result,
+                                          ErrorCode internal_error_code) = 0;
+
+  // Helper function to report download metrics after the completion of each
+  // update attempt. The following metrics are reported:
+  //
+  // |kMetricAttemptPayloadBytesDownloadedMiB|
+  // |kMetricAttemptPayloadDownloadSpeedKBps|
+  // |kMetricAttemptDownloadSource|
+  // |kMetricAttemptDownloadErrorCode|
+  // |kMetricAttemptConnectionType|
+  virtual void ReportUpdateAttemptDownloadMetrics(
+      int64_t payload_bytes_downloaded,
+      int64_t payload_download_speed_bps,
+      DownloadSource download_source,
+      metrics::DownloadErrorCode payload_download_error_code,
+      metrics::ConnectionType connection_type) = 0;
+
+  // Reports the |kAbnormalTermination| for the |kMetricAttemptResult|
+  // metric. No other metrics in the UpdateEngine.Attempt.* namespace
+  // will be reported.
+  virtual void ReportAbnormallyTerminatedUpdateAttemptMetrics() = 0;
+
+  // Helper function to report the after the completion of a successful
+  // update attempt. The following metrics are reported:
+  //
+  //  |kMetricSuccessfulUpdateAttemptCount|
+  //  |kMetricSuccessfulUpdateUpdatesAbandonedCount|
+  //  |kMetricSuccessfulUpdatePayloadType|
+  //  |kMetricSuccessfulUpdatePayloadSizeMiB|
+  //  |kMetricSuccessfulUpdateBytesDownloadedMiBHttpsServer|
+  //  |kMetricSuccessfulUpdateBytesDownloadedMiBHttpServer|
+  //  |kMetricSuccessfulUpdateBytesDownloadedMiBHttpPeer|
+  //  |kMetricSuccessfulUpdateBytesDownloadedMiB|
+  //  |kMetricSuccessfulUpdateDownloadSourcesUsed|
+  //  |kMetricSuccessfulUpdateDownloadOverheadPercentage|
+  //  |kMetricSuccessfulUpdateTotalDurationMinutes|
+  //  |kMetricSuccessfulUpdateRebootCount|
+  //  |kMetricSuccessfulUpdateUrlSwitchCount|
+  //
+  // The values for the |kMetricSuccessfulUpdateDownloadSourcesUsed| are
+  // |kMetricSuccessfulUpdateBytesDownloadedMiB| metrics automatically
+  // calculated from examining the |num_bytes_downloaded| array.
+  virtual void ReportSuccessfulUpdateMetrics(
+      int attempt_count,
+      int updates_abandoned_count,
+      PayloadType payload_type,
+      int64_t payload_size,
+      int64_t num_bytes_downloaded[kNumDownloadSources],
+      int download_overhead_percentage,
+      base::TimeDelta total_duration,
+      int reboot_count,
+      int url_switch_count) = 0;
+
+  // Helper function to report the after the completion of a SSL certificate
+  // check. One of the following metrics is reported:
+  //
+  //  |kMetricCertificateCheckUpdateCheck|
+  //  |kMetricCertificateCheckDownload|
+  virtual void ReportCertificateCheckMetrics(ServerToCheck server_to_check,
+                                             CertificateCheckResult result) = 0;
+
+  // Helper function to report the number failed update attempts. The following
+  // metrics are reported:
+  //
+  // |kMetricFailedUpdateCount|
+  virtual void ReportFailedUpdateCount(int target_attempt) = 0;
+
+  // Helper function to report the time interval in minutes between a
+  // successful update and the reboot into the updated system. The following
+  // metrics are reported:
+  //
+  // |kMetricTimeToRebootMinutes|
+  virtual void ReportTimeToReboot(int time_to_reboot_minutes) = 0;
+
+  // Helper function to report the source of installation data. The following
+  // metrics are reported:
+  //
+  // |kMetricInstallDateProvisioningSource|
+  virtual void ReportInstallDateProvisioningSource(int source, int max) = 0;
+};
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_METRICS_REPORTER_INTERFACE_H_
diff --git a/metrics_reporter_omaha.cc b/metrics_reporter_omaha.cc
new file mode 100644
index 0000000..0397b83
--- /dev/null
+++ b/metrics_reporter_omaha.cc
@@ -0,0 +1,538 @@
+//
+// Copyright (C) 2014 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/metrics_reporter_omaha.h"
+
+#include <memory>
+#include <string>
+
+#include <base/logging.h>
+#include <metrics/metrics_library.h>
+
+#include "update_engine/common/clock_interface.h"
+#include "update_engine/common/constants.h"
+#include "update_engine/common/prefs_interface.h"
+#include "update_engine/common/utils.h"
+#include "update_engine/metrics_utils.h"
+#include "update_engine/system_state.h"
+
+using std::string;
+
+namespace chromeos_update_engine {
+
+namespace metrics {
+
+// UpdateEngine.Daily.* metrics.
+const char kMetricDailyOSAgeDays[] = "UpdateEngine.Daily.OSAgeDays";
+
+// UpdateEngine.Check.* metrics.
+const char kMetricCheckDownloadErrorCode[] =
+    "UpdateEngine.Check.DownloadErrorCode";
+const char kMetricCheckReaction[] = "UpdateEngine.Check.Reaction";
+const char kMetricCheckResult[] = "UpdateEngine.Check.Result";
+const char kMetricCheckTimeSinceLastCheckMinutes[] =
+    "UpdateEngine.Check.TimeSinceLastCheckMinutes";
+const char kMetricCheckTimeSinceLastCheckUptimeMinutes[] =
+    "UpdateEngine.Check.TimeSinceLastCheckUptimeMinutes";
+
+// UpdateEngine.Attempt.* metrics.
+const char kMetricAttemptNumber[] = "UpdateEngine.Attempt.Number";
+const char kMetricAttemptPayloadType[] = "UpdateEngine.Attempt.PayloadType";
+const char kMetricAttemptPayloadSizeMiB[] =
+    "UpdateEngine.Attempt.PayloadSizeMiB";
+const char kMetricAttemptConnectionType[] =
+    "UpdateEngine.Attempt.ConnectionType";
+const char kMetricAttemptDurationMinutes[] =
+    "UpdateEngine.Attempt.DurationMinutes";
+const char kMetricAttemptDurationUptimeMinutes[] =
+    "UpdateEngine.Attempt.DurationUptimeMinutes";
+const char kMetricAttemptTimeSinceLastAttemptMinutes[] =
+    "UpdateEngine.Attempt.TimeSinceLastAttemptMinutes";
+const char kMetricAttemptTimeSinceLastAttemptUptimeMinutes[] =
+    "UpdateEngine.Attempt.TimeSinceLastAttemptUptimeMinutes";
+const char kMetricAttemptPayloadBytesDownloadedMiB[] =
+    "UpdateEngine.Attempt.PayloadBytesDownloadedMiB";
+const char kMetricAttemptPayloadDownloadSpeedKBps[] =
+    "UpdateEngine.Attempt.PayloadDownloadSpeedKBps";
+const char kMetricAttemptDownloadSource[] =
+    "UpdateEngine.Attempt.DownloadSource";
+const char kMetricAttemptResult[] = "UpdateEngine.Attempt.Result";
+const char kMetricAttemptInternalErrorCode[] =
+    "UpdateEngine.Attempt.InternalErrorCode";
+const char kMetricAttemptDownloadErrorCode[] =
+    "UpdateEngine.Attempt.DownloadErrorCode";
+
+// UpdateEngine.SuccessfulUpdate.* metrics.
+const char kMetricSuccessfulUpdateAttemptCount[] =
+    "UpdateEngine.SuccessfulUpdate.AttemptCount";
+const char kMetricSuccessfulUpdateBytesDownloadedMiB[] =
+    "UpdateEngine.SuccessfulUpdate.BytesDownloadedMiB";
+const char kMetricSuccessfulUpdateDownloadOverheadPercentage[] =
+    "UpdateEngine.SuccessfulUpdate.DownloadOverheadPercentage";
+const char kMetricSuccessfulUpdateDownloadSourcesUsed[] =
+    "UpdateEngine.SuccessfulUpdate.DownloadSourcesUsed";
+const char kMetricSuccessfulUpdatePayloadType[] =
+    "UpdateEngine.SuccessfulUpdate.PayloadType";
+const char kMetricSuccessfulUpdatePayloadSizeMiB[] =
+    "UpdateEngine.SuccessfulUpdate.PayloadSizeMiB";
+const char kMetricSuccessfulUpdateRebootCount[] =
+    "UpdateEngine.SuccessfulUpdate.RebootCount";
+const char kMetricSuccessfulUpdateTotalDurationMinutes[] =
+    "UpdateEngine.SuccessfulUpdate.TotalDurationMinutes";
+const char kMetricSuccessfulUpdateUpdatesAbandonedCount[] =
+    "UpdateEngine.SuccessfulUpdate.UpdatesAbandonedCount";
+const char kMetricSuccessfulUpdateUrlSwitchCount[] =
+    "UpdateEngine.SuccessfulUpdate.UrlSwitchCount";
+
+// UpdateEngine.Rollback.* metric.
+const char kMetricRollbackResult[] = "UpdateEngine.Rollback.Result";
+
+// UpdateEngine.CertificateCheck.* metrics.
+const char kMetricCertificateCheckUpdateCheck[] =
+    "UpdateEngine.CertificateCheck.UpdateCheck";
+const char kMetricCertificateCheckDownload[] =
+    "UpdateEngine.CertificateCheck.Download";
+
+// UpdateEngine.* metrics.
+const char kMetricFailedUpdateCount[] = "UpdateEngine.FailedUpdateCount";
+const char kMetricInstallDateProvisioningSource[] =
+    "UpdateEngine.InstallDateProvisioningSource";
+const char kMetricTimeToRebootMinutes[] = "UpdateEngine.TimeToRebootMinutes";
+
+std::unique_ptr<MetricsReporterInterface> CreateMetricsReporter() {
+  return std::make_unique<MetricsReporterOmaha>();
+}
+
+}  // namespace metrics
+
+MetricsReporterOmaha::MetricsReporterOmaha()
+    : metrics_lib_(new MetricsLibrary()) {}
+
+void MetricsReporterOmaha::Initialize() {
+  metrics_lib_->Init();
+}
+
+void MetricsReporterOmaha::ReportDailyMetrics(base::TimeDelta os_age) {
+  string metric = metrics::kMetricDailyOSAgeDays;
+  LOG(INFO) << "Uploading " << utils::FormatTimeDelta(os_age) << " for metric "
+            << metric;
+  metrics_lib_->SendToUMA(metric,
+                          static_cast<int>(os_age.InDays()),
+                          0,       // min: 0 days
+                          6 * 30,  // max: 6 months (approx)
+                          50);     // num_buckets
+}
+
+void MetricsReporterOmaha::ReportUpdateCheckMetrics(
+    SystemState* system_state,
+    metrics::CheckResult result,
+    metrics::CheckReaction reaction,
+    metrics::DownloadErrorCode download_error_code) {
+  string metric;
+  int value;
+  int max_value;
+
+  if (result != metrics::CheckResult::kUnset) {
+    metric = metrics::kMetricCheckResult;
+    value = static_cast<int>(result);
+    max_value = static_cast<int>(metrics::CheckResult::kNumConstants) - 1;
+    LOG(INFO) << "Sending " << value << " for metric " << metric << " (enum)";
+    metrics_lib_->SendEnumToUMA(metric, value, max_value);
+  }
+  if (reaction != metrics::CheckReaction::kUnset) {
+    metric = metrics::kMetricCheckReaction;
+    value = static_cast<int>(reaction);
+    max_value = static_cast<int>(metrics::CheckReaction::kNumConstants) - 1;
+    LOG(INFO) << "Sending " << value << " for metric " << metric << " (enum)";
+    metrics_lib_->SendEnumToUMA(metric, value, max_value);
+  }
+  if (download_error_code != metrics::DownloadErrorCode::kUnset) {
+    metric = metrics::kMetricCheckDownloadErrorCode;
+    value = static_cast<int>(download_error_code);
+    LOG(INFO) << "Sending " << value << " for metric " << metric << " (sparse)";
+    metrics_lib_->SendSparseToUMA(metric, value);
+  }
+
+  base::TimeDelta time_since_last;
+  if (metrics_utils::WallclockDurationHelper(
+          system_state,
+          kPrefsMetricsCheckLastReportingTime,
+          &time_since_last)) {
+    metric = metrics::kMetricCheckTimeSinceLastCheckMinutes;
+    LOG(INFO) << "Sending " << utils::FormatTimeDelta(time_since_last)
+              << " for metric " << metric;
+    metrics_lib_->SendToUMA(metric,
+                            time_since_last.InMinutes(),
+                            0,             // min: 0 min
+                            30 * 24 * 60,  // max: 30 days
+                            50);           // num_buckets
+  }
+
+  base::TimeDelta uptime_since_last;
+  static int64_t uptime_since_last_storage = 0;
+  if (metrics_utils::MonotonicDurationHelper(
+          system_state, &uptime_since_last_storage, &uptime_since_last)) {
+    metric = metrics::kMetricCheckTimeSinceLastCheckUptimeMinutes;
+    LOG(INFO) << "Sending " << utils::FormatTimeDelta(uptime_since_last)
+              << " for metric " << metric;
+    metrics_lib_->SendToUMA(metric,
+                            uptime_since_last.InMinutes(),
+                            0,             // min: 0 min
+                            30 * 24 * 60,  // max: 30 days
+                            50);           // num_buckets
+  }
+}
+
+void MetricsReporterOmaha::ReportAbnormallyTerminatedUpdateAttemptMetrics() {
+  string metric = metrics::kMetricAttemptResult;
+  metrics::AttemptResult attempt_result =
+      metrics::AttemptResult::kAbnormalTermination;
+
+  LOG(INFO) << "Uploading " << static_cast<int>(attempt_result)
+            << " for metric " << metric;
+  metrics_lib_->SendEnumToUMA(
+      metric,
+      static_cast<int>(attempt_result),
+      static_cast<int>(metrics::AttemptResult::kNumConstants));
+}
+
+void MetricsReporterOmaha::ReportUpdateAttemptMetrics(
+    SystemState* system_state,
+    int attempt_number,
+    PayloadType payload_type,
+    base::TimeDelta duration,
+    base::TimeDelta duration_uptime,
+    int64_t payload_size,
+    metrics::AttemptResult attempt_result,
+    ErrorCode internal_error_code) {
+  string metric = metrics::kMetricAttemptNumber;
+  LOG(INFO) << "Uploading " << attempt_number << " for metric " << metric;
+  metrics_lib_->SendToUMA(metric,
+                          attempt_number,
+                          0,    // min: 0 attempts
+                          49,   // max: 49 attempts
+                          50);  // num_buckets
+
+  metric = metrics::kMetricAttemptPayloadType;
+  LOG(INFO) << "Uploading " << utils::ToString(payload_type) << " for metric "
+            << metric;
+  metrics_lib_->SendEnumToUMA(metric, payload_type, kNumPayloadTypes);
+
+  metric = metrics::kMetricAttemptDurationMinutes;
+  LOG(INFO) << "Uploading " << utils::FormatTimeDelta(duration)
+            << " for metric " << metric;
+  metrics_lib_->SendToUMA(metric,
+                          duration.InMinutes(),
+                          0,             // min: 0 min
+                          10 * 24 * 60,  // max: 10 days
+                          50);           // num_buckets
+
+  metric = metrics::kMetricAttemptDurationUptimeMinutes;
+  LOG(INFO) << "Uploading " << utils::FormatTimeDelta(duration_uptime)
+            << " for metric " << metric;
+  metrics_lib_->SendToUMA(metric,
+                          duration_uptime.InMinutes(),
+                          0,             // min: 0 min
+                          10 * 24 * 60,  // max: 10 days
+                          50);           // num_buckets
+
+  metric = metrics::kMetricAttemptPayloadSizeMiB;
+  int64_t payload_size_mib = payload_size / kNumBytesInOneMiB;
+  LOG(INFO) << "Uploading " << payload_size_mib << " for metric " << metric;
+  metrics_lib_->SendToUMA(metric,
+                          payload_size_mib,
+                          0,     // min: 0 MiB
+                          1024,  // max: 1024 MiB = 1 GiB
+                          50);   // num_buckets
+
+
+
+  metric = metrics::kMetricAttemptResult;
+  LOG(INFO) << "Uploading " << static_cast<int>(attempt_result)
+            << " for metric " << metric;
+  metrics_lib_->SendEnumToUMA(
+      metric,
+      static_cast<int>(attempt_result),
+      static_cast<int>(metrics::AttemptResult::kNumConstants));
+
+  if (internal_error_code != ErrorCode::kSuccess) {
+    metric = metrics::kMetricAttemptInternalErrorCode;
+    LOG(INFO) << "Uploading " << internal_error_code << " for metric "
+              << metric;
+    metrics_lib_->SendEnumToUMA(metric,
+                                static_cast<int>(internal_error_code),
+                                static_cast<int>(ErrorCode::kUmaReportedMax));
+  }
+
+  base::TimeDelta time_since_last;
+  if (metrics_utils::WallclockDurationHelper(
+          system_state,
+          kPrefsMetricsAttemptLastReportingTime,
+          &time_since_last)) {
+    metric = metrics::kMetricAttemptTimeSinceLastAttemptMinutes;
+    LOG(INFO) << "Sending " << utils::FormatTimeDelta(time_since_last)
+              << " for metric " << metric;
+    metrics_lib_->SendToUMA(metric,
+                            time_since_last.InMinutes(),
+                            0,             // min: 0 min
+                            30 * 24 * 60,  // max: 30 days
+                            50);           // num_buckets
+  }
+
+  static int64_t uptime_since_last_storage = 0;
+  base::TimeDelta uptime_since_last;
+  if (metrics_utils::MonotonicDurationHelper(
+          system_state, &uptime_since_last_storage, &uptime_since_last)) {
+    metric = metrics::kMetricAttemptTimeSinceLastAttemptUptimeMinutes;
+    LOG(INFO) << "Sending " << utils::FormatTimeDelta(uptime_since_last)
+              << " for metric " << metric;
+    metrics_lib_->SendToUMA(metric,
+                            uptime_since_last.InMinutes(),
+                            0,             // min: 0 min
+                            30 * 24 * 60,  // max: 30 days
+                            50);           // num_buckets
+  }
+}
+
+void MetricsReporterOmaha::ReportUpdateAttemptDownloadMetrics(
+    int64_t payload_bytes_downloaded,
+    int64_t payload_download_speed_bps,
+    DownloadSource download_source,
+    metrics::DownloadErrorCode payload_download_error_code,
+    metrics::ConnectionType connection_type) {
+  string metric = metrics::kMetricAttemptPayloadBytesDownloadedMiB;
+  int64_t payload_bytes_downloaded_mib =
+      payload_bytes_downloaded / kNumBytesInOneMiB;
+  LOG(INFO) << "Uploading " << payload_bytes_downloaded_mib << " for metric "
+            << metric;
+  metrics_lib_->SendToUMA(metric,
+                          payload_bytes_downloaded_mib,
+                          0,     // min: 0 MiB
+                          1024,  // max: 1024 MiB = 1 GiB
+                          50);   // num_buckets
+
+  metric = metrics::kMetricAttemptPayloadDownloadSpeedKBps;
+  int64_t payload_download_speed_kbps = payload_download_speed_bps / 1000;
+  LOG(INFO) << "Uploading " << payload_download_speed_kbps << " for metric "
+            << metric;
+  metrics_lib_->SendToUMA(metric,
+                          payload_download_speed_kbps,
+                          0,          // min: 0 kB/s
+                          10 * 1000,  // max: 10000 kB/s = 10 MB/s
+                          50);        // num_buckets
+
+  metric = metrics::kMetricAttemptDownloadSource;
+  LOG(INFO) << "Uploading " << download_source << " for metric " << metric;
+  metrics_lib_->SendEnumToUMA(metric, download_source, kNumDownloadSources);
+
+  if (payload_download_error_code != metrics::DownloadErrorCode::kUnset) {
+    metric = metrics::kMetricAttemptDownloadErrorCode;
+    LOG(INFO) << "Uploading " << static_cast<int>(payload_download_error_code)
+              << " for metric " << metric << " (sparse)";
+    metrics_lib_->SendSparseToUMA(
+        metric, static_cast<int>(payload_download_error_code));
+  }
+
+  metric = metrics::kMetricAttemptConnectionType;
+  LOG(INFO) << "Uploading " << static_cast<int>(connection_type)
+            << " for metric " << metric;
+  metrics_lib_->SendEnumToUMA(
+      metric,
+      static_cast<int>(connection_type),
+      static_cast<int>(metrics::ConnectionType::kNumConstants));
+}
+
+void MetricsReporterOmaha::ReportSuccessfulUpdateMetrics(
+    int attempt_count,
+    int updates_abandoned_count,
+    PayloadType payload_type,
+    int64_t payload_size,
+    int64_t num_bytes_downloaded[kNumDownloadSources],
+    int download_overhead_percentage,
+    base::TimeDelta total_duration,
+    int reboot_count,
+    int url_switch_count) {
+  string metric = metrics::kMetricSuccessfulUpdatePayloadSizeMiB;
+  int64_t mbs = payload_size / kNumBytesInOneMiB;
+  LOG(INFO) << "Uploading " << mbs << " (MiBs) for metric " << metric;
+  metrics_lib_->SendToUMA(metric,
+                          mbs,
+                          0,     // min: 0 MiB
+                          1024,  // max: 1024 MiB = 1 GiB
+                          50);   // num_buckets
+
+  int64_t total_bytes = 0;
+  int download_sources_used = 0;
+  for (int i = 0; i < kNumDownloadSources + 1; i++) {
+    DownloadSource source = static_cast<DownloadSource>(i);
+
+    // Only consider this download source (and send byte counts) as
+    // having been used if we downloaded a non-trivial amount of bytes
+    // (e.g. at least 1 MiB) that contributed to the
+    // update. Otherwise we're going to end up with a lot of zero-byte
+    // events in the histogram.
+
+    metric = metrics::kMetricSuccessfulUpdateBytesDownloadedMiB;
+    if (i < kNumDownloadSources) {
+      metric += utils::ToString(source);
+      mbs = num_bytes_downloaded[i] / kNumBytesInOneMiB;
+      total_bytes += num_bytes_downloaded[i];
+      if (mbs > 0)
+        download_sources_used |= (1 << i);
+    } else {
+      mbs = total_bytes / kNumBytesInOneMiB;
+    }
+
+    if (mbs > 0) {
+      LOG(INFO) << "Uploading " << mbs << " (MiBs) for metric " << metric;
+      metrics_lib_->SendToUMA(metric,
+                              mbs,
+                              0,     // min: 0 MiB
+                              1024,  // max: 1024 MiB = 1 GiB
+                              50);   // num_buckets
+    }
+  }
+
+  metric = metrics::kMetricSuccessfulUpdateDownloadSourcesUsed;
+  LOG(INFO) << "Uploading 0x" << std::hex << download_sources_used
+            << " (bit flags) for metric " << metric;
+  metrics_lib_->SendToUMA(metric,
+                          download_sources_used,
+                          0,                               // min
+                          (1 << kNumDownloadSources) - 1,  // max
+                          1 << kNumDownloadSources);       // num_buckets
+
+  metric = metrics::kMetricSuccessfulUpdateDownloadOverheadPercentage;
+  LOG(INFO) << "Uploading " << download_overhead_percentage << "% for metric "
+            << metric;
+  metrics_lib_->SendToUMA(metric,
+                          download_overhead_percentage,
+                          0,     // min: 0% overhead
+                          1000,  // max: 1000% overhead
+                          50);   // num_buckets
+
+  metric = metrics::kMetricSuccessfulUpdateUrlSwitchCount;
+  LOG(INFO) << "Uploading " << url_switch_count << " (count) for metric "
+            << metric;
+  metrics_lib_->SendToUMA(metric,
+                          url_switch_count,
+                          0,    // min: 0 URL switches
+                          49,   // max: 49 URL switches
+                          50);  // num_buckets
+
+  metric = metrics::kMetricSuccessfulUpdateTotalDurationMinutes;
+  LOG(INFO) << "Uploading " << utils::FormatTimeDelta(total_duration)
+            << " for metric " << metric;
+  metrics_lib_->SendToUMA(metric,
+                          static_cast<int>(total_duration.InMinutes()),
+                          0,              // min: 0 min
+                          365 * 24 * 60,  // max: 365 days ~= 1 year
+                          50);            // num_buckets
+
+  metric = metrics::kMetricSuccessfulUpdateRebootCount;
+  LOG(INFO) << "Uploading reboot count of " << reboot_count << " for metric "
+            << metric;
+  metrics_lib_->SendToUMA(metric,
+                          reboot_count,
+                          0,    // min: 0 reboots
+                          49,   // max: 49 reboots
+                          50);  // num_buckets
+
+  metric = metrics::kMetricSuccessfulUpdatePayloadType;
+  metrics_lib_->SendEnumToUMA(metric, payload_type, kNumPayloadTypes);
+  LOG(INFO) << "Uploading " << utils::ToString(payload_type) << " for metric "
+            << metric;
+
+  metric = metrics::kMetricSuccessfulUpdateAttemptCount;
+  metrics_lib_->SendToUMA(metric,
+                          attempt_count,
+                          1,    // min: 1 attempt
+                          50,   // max: 50 attempts
+                          50);  // num_buckets
+  LOG(INFO) << "Uploading " << attempt_count << " for metric " << metric;
+
+  metric = metrics::kMetricSuccessfulUpdateUpdatesAbandonedCount;
+  LOG(INFO) << "Uploading " << updates_abandoned_count << " (count) for metric "
+            << metric;
+  metrics_lib_->SendToUMA(metric,
+                          updates_abandoned_count,
+                          0,    // min: 0 counts
+                          49,   // max: 49 counts
+                          50);  // num_buckets
+}
+
+void MetricsReporterOmaha::ReportRollbackMetrics(
+    metrics::RollbackResult result) {
+  string metric = metrics::kMetricRollbackResult;
+  int value = static_cast<int>(result);
+  LOG(INFO) << "Sending " << value << " for metric " << metric << " (enum)";
+  metrics_lib_->SendEnumToUMA(
+      metric, value, static_cast<int>(metrics::RollbackResult::kNumConstants));
+}
+
+void MetricsReporterOmaha::ReportCertificateCheckMetrics(
+    ServerToCheck server_to_check, CertificateCheckResult result) {
+  string metric;
+  switch (server_to_check) {
+    case ServerToCheck::kUpdate:
+      metric = metrics::kMetricCertificateCheckUpdateCheck;
+      break;
+    case ServerToCheck::kDownload:
+      metric = metrics::kMetricCertificateCheckDownload;
+      break;
+    case ServerToCheck::kNone:
+      return;
+  }
+  LOG(INFO) << "Uploading " << static_cast<int>(result) << " for metric "
+            << metric;
+  metrics_lib_->SendEnumToUMA(
+      metric,
+      static_cast<int>(result),
+      static_cast<int>(CertificateCheckResult::kNumConstants));
+}
+
+void MetricsReporterOmaha::ReportFailedUpdateCount(int target_attempt) {
+  string metric = metrics::kMetricFailedUpdateCount;
+  metrics_lib_->SendToUMA(metric,
+                          target_attempt,
+                          1,   // min value
+                          50,  // max value
+                          kNumDefaultUmaBuckets);
+
+  LOG(INFO) << "Uploading " << target_attempt << " (count) for metric "
+            << metric;
+}
+
+void MetricsReporterOmaha::ReportTimeToReboot(int time_to_reboot_minutes) {
+  string metric = metrics::kMetricTimeToRebootMinutes;
+  metrics_lib_->SendToUMA(metric,
+                          time_to_reboot_minutes,
+                          0,             // min: 0 minute
+                          30 * 24 * 60,  // max: 1 month (approx)
+                          kNumDefaultUmaBuckets);
+
+  LOG(INFO) << "Uploading " << time_to_reboot_minutes << " for metric "
+            << metric;
+}
+
+void MetricsReporterOmaha::ReportInstallDateProvisioningSource(int source,
+                                                               int max) {
+  metrics_lib_->SendEnumToUMA(metrics::kMetricInstallDateProvisioningSource,
+                              source,  // Sample.
+                              max);
+}
+
+}  // namespace chromeos_update_engine
diff --git a/metrics_reporter_omaha.h b/metrics_reporter_omaha.h
new file mode 100644
index 0000000..c19fe86
--- /dev/null
+++ b/metrics_reporter_omaha.h
@@ -0,0 +1,156 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_METRICS_REPORTER_OMAHA_H_
+#define UPDATE_ENGINE_METRICS_REPORTER_OMAHA_H_
+
+#include <memory>
+
+#include <base/time/time.h>
+#include <metrics/metrics_library.h>
+
+#include "update_engine/certificate_checker.h"
+#include "update_engine/common/constants.h"
+#include "update_engine/common/error_code.h"
+#include "update_engine/metrics_constants.h"
+#include "update_engine/metrics_reporter_interface.h"
+#include "update_engine/system_state.h"
+
+namespace chromeos_update_engine {
+
+class SystemState;
+
+namespace metrics {
+
+// UpdateEngine.Daily.* metrics.
+extern const char kMetricDailyOSAgeDays[];
+
+// UpdateEngine.Check.* metrics.
+extern const char kMetricCheckDownloadErrorCode[];
+extern const char kMetricCheckReaction[];
+extern const char kMetricCheckResult[];
+extern const char kMetricCheckTimeSinceLastCheckMinutes[];
+extern const char kMetricCheckTimeSinceLastCheckUptimeMinutes[];
+
+// UpdateEngine.Attempt.* metrics.
+extern const char kMetricAttemptNumber[];
+extern const char kMetricAttemptPayloadType[];
+extern const char kMetricAttemptPayloadSizeMiB[];
+extern const char kMetricAttemptConnectionType[];
+extern const char kMetricAttemptDurationMinutes[];
+extern const char kMetricAttemptDurationUptimeMinutes[];
+extern const char kMetricAttemptTimeSinceLastAttemptMinutes[];
+extern const char kMetricAttemptTimeSinceLastAttemptUptimeMinutes[];
+extern const char kMetricAttemptPayloadBytesDownloadedMiB[];
+extern const char kMetricAttemptPayloadDownloadSpeedKBps[];
+extern const char kMetricAttemptDownloadSource[];
+extern const char kMetricAttemptResult[];
+extern const char kMetricAttemptInternalErrorCode[];
+extern const char kMetricAttemptDownloadErrorCode[];
+
+// UpdateEngine.SuccessfulUpdate.* metrics.
+extern const char kMetricSuccessfulUpdateAttemptCount[];
+extern const char kMetricSuccessfulUpdateBytesDownloadedMiB[];
+extern const char kMetricSuccessfulUpdateDownloadOverheadPercentage[];
+extern const char kMetricSuccessfulUpdateDownloadSourcesUsed[];
+extern const char kMetricSuccessfulUpdatePayloadType[];
+extern const char kMetricSuccessfulUpdatePayloadSizeMiB[];
+extern const char kMetricSuccessfulUpdateRebootCount[];
+extern const char kMetricSuccessfulUpdateTotalDurationMinutes[];
+extern const char kMetricSuccessfulUpdateUpdatesAbandonedCount[];
+extern const char kMetricSuccessfulUpdateUrlSwitchCount[];
+
+// UpdateEngine.Rollback.* metric.
+extern const char kMetricRollbackResult[];
+
+// UpdateEngine.CertificateCheck.* metrics.
+extern const char kMetricCertificateCheckUpdateCheck[];
+extern const char kMetricCertificateCheckDownload[];
+
+// UpdateEngine.* metrics.
+extern const char kMetricFailedUpdateCount[];
+extern const char kMetricInstallDateProvisioningSource[];
+extern const char kMetricTimeToRebootMinutes[];
+
+}  // namespace metrics
+
+class MetricsReporterOmaha : public MetricsReporterInterface {
+ public:
+  MetricsReporterOmaha();
+
+  ~MetricsReporterOmaha() override = default;
+
+  void Initialize() override;
+
+  void ReportRollbackMetrics(metrics::RollbackResult result) override;
+
+  void ReportDailyMetrics(base::TimeDelta os_age) override;
+
+  void ReportUpdateCheckMetrics(
+      SystemState* system_state,
+      metrics::CheckResult result,
+      metrics::CheckReaction reaction,
+      metrics::DownloadErrorCode download_error_code) override;
+
+  void ReportUpdateAttemptMetrics(SystemState* system_state,
+                                  int attempt_number,
+                                  PayloadType payload_type,
+                                  base::TimeDelta duration,
+                                  base::TimeDelta duration_uptime,
+                                  int64_t payload_size,
+                                  metrics::AttemptResult attempt_result,
+                                  ErrorCode internal_error_code) override;
+
+  void ReportUpdateAttemptDownloadMetrics(
+      int64_t payload_bytes_downloaded,
+      int64_t payload_download_speed_bps,
+      DownloadSource download_source,
+      metrics::DownloadErrorCode payload_download_error_code,
+      metrics::ConnectionType connection_type) override;
+
+  void ReportAbnormallyTerminatedUpdateAttemptMetrics() override;
+
+  void ReportSuccessfulUpdateMetrics(
+      int attempt_count,
+      int updates_abandoned_count,
+      PayloadType payload_type,
+      int64_t payload_size,
+      int64_t num_bytes_downloaded[kNumDownloadSources],
+      int download_overhead_percentage,
+      base::TimeDelta total_duration,
+      int reboot_count,
+      int url_switch_count) override;
+
+  void ReportCertificateCheckMetrics(ServerToCheck server_to_check,
+                                     CertificateCheckResult result) override;
+
+  void ReportFailedUpdateCount(int target_attempt) override;
+
+  void ReportTimeToReboot(int time_to_reboot_minutes) override;
+
+  void ReportInstallDateProvisioningSource(int source, int max) override;
+
+ private:
+  friend class MetricsReporterOmahaTest;
+
+  std::unique_ptr<MetricsLibraryInterface> metrics_lib_;
+
+  DISALLOW_COPY_AND_ASSIGN(MetricsReporterOmaha);
+};  // class metrics
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_METRICS_REPORTER_OMAHA_H_
diff --git a/metrics_reporter_omaha_unittest.cc b/metrics_reporter_omaha_unittest.cc
new file mode 100644
index 0000000..76e33c6
--- /dev/null
+++ b/metrics_reporter_omaha_unittest.cc
@@ -0,0 +1,394 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/metrics_reporter_omaha.h"
+
+#include <memory>
+#include <string>
+
+#include <base/time/time.h>
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+#include <metrics/metrics_library_mock.h>
+
+#include "update_engine/common/fake_clock.h"
+#include "update_engine/common/fake_prefs.h"
+#include "update_engine/fake_system_state.h"
+
+using base::TimeDelta;
+using testing::AnyNumber;
+using testing::_;
+
+namespace chromeos_update_engine {
+class MetricsReporterOmahaTest : public ::testing::Test {
+ protected:
+  MetricsReporterOmahaTest() = default;
+
+  // Reset the metrics_lib_ to a mock library.
+  void SetUp() override {
+    mock_metrics_lib_ = new testing::NiceMock<MetricsLibraryMock>();
+    reporter_.metrics_lib_.reset(mock_metrics_lib_);
+  }
+
+  testing::NiceMock<MetricsLibraryMock>* mock_metrics_lib_;
+  MetricsReporterOmaha reporter_;
+};
+
+TEST_F(MetricsReporterOmahaTest, ReportDailyMetrics) {
+  TimeDelta age = TimeDelta::FromDays(10);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendToUMA(metrics::kMetricDailyOSAgeDays, _, _, _, _))
+      .Times(1);
+
+  reporter_.ReportDailyMetrics(age);
+}
+
+TEST_F(MetricsReporterOmahaTest, ReportUpdateCheckMetrics) {
+  FakeSystemState fake_system_state;
+  FakeClock fake_clock;
+  FakePrefs fake_prefs;
+
+  // We need to execute the report twice to test the time since last report.
+  fake_system_state.set_clock(&fake_clock);
+  fake_system_state.set_prefs(&fake_prefs);
+  fake_clock.SetWallclockTime(base::Time::FromInternalValue(1000000));
+  fake_clock.SetMonotonicTime(base::Time::FromInternalValue(1000000));
+
+  metrics::CheckResult result = metrics::CheckResult::kUpdateAvailable;
+  metrics::CheckReaction reaction = metrics::CheckReaction::kIgnored;
+  metrics::DownloadErrorCode error_code =
+      metrics::DownloadErrorCode::kHttpStatus200;
+
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendEnumToUMA(metrics::kMetricCheckResult, static_cast<int>(result), _))
+      .Times(2);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendEnumToUMA(
+                  metrics::kMetricCheckReaction, static_cast<int>(reaction), _))
+      .Times(2);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendSparseToUMA(metrics::kMetricCheckDownloadErrorCode,
+                              static_cast<int>(error_code)))
+      .Times(2);
+
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(metrics::kMetricCheckTimeSinceLastCheckMinutes, 1, _, _, _))
+      .Times(1);
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(
+          metrics::kMetricCheckTimeSinceLastCheckUptimeMinutes, 1, _, _, _))
+      .Times(1);
+
+  reporter_.ReportUpdateCheckMetrics(
+      &fake_system_state, result, reaction, error_code);
+
+  // Advance the clock by 1 minute and report the same metrics again.
+  fake_clock.SetWallclockTime(base::Time::FromInternalValue(61000000));
+  fake_clock.SetMonotonicTime(base::Time::FromInternalValue(61000000));
+  reporter_.ReportUpdateCheckMetrics(
+      &fake_system_state, result, reaction, error_code);
+}
+
+TEST_F(MetricsReporterOmahaTest,
+       ReportAbnormallyTerminatedUpdateAttemptMetrics) {
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendEnumToUMA(metrics::kMetricAttemptResult,
+                            static_cast<int>(
+                                metrics::AttemptResult::kAbnormalTermination),
+                            _))
+      .Times(1);
+
+  reporter_.ReportAbnormallyTerminatedUpdateAttemptMetrics();
+}
+
+TEST_F(MetricsReporterOmahaTest, ReportUpdateAttemptMetrics) {
+  FakeSystemState fake_system_state;
+  FakeClock fake_clock;
+  FakePrefs fake_prefs;
+
+  fake_system_state.set_clock(&fake_clock);
+  fake_system_state.set_prefs(&fake_prefs);
+  fake_clock.SetWallclockTime(base::Time::FromInternalValue(1000000));
+  fake_clock.SetMonotonicTime(base::Time::FromInternalValue(1000000));
+
+  int attempt_number = 1;
+  PayloadType payload_type = kPayloadTypeFull;
+  TimeDelta duration = TimeDelta::FromMinutes(1000);
+  TimeDelta duration_uptime = TimeDelta::FromMinutes(1000);
+
+  int64_t payload_size = 100 * kNumBytesInOneMiB;
+
+  metrics::AttemptResult attempt_result =
+      metrics::AttemptResult::kInternalError;
+  ErrorCode internal_error_code = ErrorCode::kDownloadInvalidMetadataSignature;
+
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendToUMA(metrics::kMetricAttemptNumber, attempt_number, _, _, _))
+      .Times(2);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendEnumToUMA(metrics::kMetricAttemptPayloadType,
+                            static_cast<int>(payload_type),
+                            _))
+      .Times(2);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendToUMA(metrics::kMetricAttemptDurationMinutes,
+                        duration.InMinutes(),
+                        _,
+                        _,
+                        _))
+      .Times(2);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendToUMA(metrics::kMetricAttemptDurationUptimeMinutes,
+                        duration_uptime.InMinutes(),
+                        _,
+                        _,
+                        _))
+      .Times(2);
+
+
+  // Check the report of attempt result.
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendEnumToUMA(
+          metrics::kMetricAttemptResult, static_cast<int>(attempt_result), _))
+      .Times(2);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendEnumToUMA(metrics::kMetricAttemptInternalErrorCode,
+                            static_cast<int>(internal_error_code),
+                            _))
+      .Times(2);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendToUMA(metrics::kMetricAttemptPayloadSizeMiB, 100, _, _, _))
+      .Times(2);
+
+  // Check the duration between two reports.
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(metrics::kMetricAttemptTimeSinceLastAttemptMinutes, 1, _, _, _))
+      .Times(1);
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(
+          metrics::kMetricAttemptTimeSinceLastAttemptUptimeMinutes, 1, _, _, _))
+      .Times(1);
+
+  reporter_.ReportUpdateAttemptMetrics(&fake_system_state,
+                                       attempt_number,
+                                       payload_type,
+                                       duration,
+                                       duration_uptime,
+                                       payload_size,
+                                       attempt_result,
+                                       internal_error_code);
+
+  // Advance the clock by 1 minute and report the same metrics again.
+  fake_clock.SetWallclockTime(base::Time::FromInternalValue(61000000));
+  fake_clock.SetMonotonicTime(base::Time::FromInternalValue(61000000));
+  reporter_.ReportUpdateAttemptMetrics(&fake_system_state,
+                                       attempt_number,
+                                       payload_type,
+                                       duration,
+                                       duration_uptime,
+                                       payload_size,
+                                       attempt_result,
+                                       internal_error_code);
+}
+
+TEST_F(MetricsReporterOmahaTest, ReportUpdateAttemptDownloadMetrics) {
+  int64_t payload_bytes_downloaded = 200 * kNumBytesInOneMiB;
+  int64_t payload_download_speed_bps = 100 * 1000;
+  DownloadSource download_source = kDownloadSourceHttpServer;
+  metrics::DownloadErrorCode payload_download_error_code =
+      metrics::DownloadErrorCode::kDownloadError;
+  metrics::ConnectionType connection_type = metrics::ConnectionType::kCellular;
+
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(metrics::kMetricAttemptPayloadBytesDownloadedMiB, 200, _, _, _))
+      .Times(1);
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(metrics::kMetricAttemptPayloadDownloadSpeedKBps, 100, _, _, _))
+      .Times(1);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendEnumToUMA(metrics::kMetricAttemptDownloadSource,
+                            static_cast<int>(download_source),
+                            _))
+      .Times(1);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendSparseToUMA(metrics::kMetricAttemptDownloadErrorCode,
+                              static_cast<int>(payload_download_error_code)))
+      .Times(1);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendEnumToUMA(metrics::kMetricAttemptConnectionType,
+                            static_cast<int>(connection_type),
+                            _))
+      .Times(1);
+
+  reporter_.ReportUpdateAttemptDownloadMetrics(payload_bytes_downloaded,
+                                               payload_download_speed_bps,
+                                               download_source,
+                                               payload_download_error_code,
+                                               connection_type);
+}
+
+TEST_F(MetricsReporterOmahaTest, ReportSuccessfulUpdateMetrics) {
+  int attempt_count = 3;
+  int updates_abandoned_count = 2;
+  PayloadType payload_type = kPayloadTypeDelta;
+  int64_t payload_size = 200 * kNumBytesInOneMiB;
+  int64_t num_bytes_downloaded[kNumDownloadSources] = {};
+  // 200MiB payload downloaded from HttpsServer.
+  num_bytes_downloaded[0] = 200 * kNumBytesInOneMiB;
+  int download_overhead_percentage = 20;
+  TimeDelta total_duration = TimeDelta::FromMinutes(30);
+  int reboot_count = 2;
+  int url_switch_count = 2;
+
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(metrics::kMetricSuccessfulUpdatePayloadSizeMiB, 200, _, _, _))
+      .Times(1);
+
+  // Check the report to both BytesDownloadedMiBHttpsServer and
+  // BytesDownloadedMiB
+  std::string DownloadedMiBMetric =
+      metrics::kMetricSuccessfulUpdateBytesDownloadedMiB;
+  DownloadedMiBMetric += "HttpsServer";
+  EXPECT_CALL(*mock_metrics_lib_, SendToUMA(DownloadedMiBMetric, 200, _, _, _))
+      .Times(1);
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(
+          metrics::kMetricSuccessfulUpdateBytesDownloadedMiB, 200, _, _, _))
+      .Times(1);
+
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(
+          metrics::kMetricSuccessfulUpdateDownloadSourcesUsed, 1, _, _, _))
+      .Times(1);
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(metrics::kMetricSuccessfulUpdateDownloadOverheadPercentage,
+                20,
+                _,
+                _,
+                _));
+
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendToUMA(metrics::kMetricSuccessfulUpdateUrlSwitchCount,
+                        url_switch_count,
+                        _,
+                        _,
+                        _))
+      .Times(1);
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(
+          metrics::kMetricSuccessfulUpdateTotalDurationMinutes, 30, _, _, _))
+      .Times(1);
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(
+          metrics::kMetricSuccessfulUpdateRebootCount, reboot_count, _, _, _))
+      .Times(1);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendEnumToUMA(
+                  metrics::kMetricSuccessfulUpdatePayloadType, payload_type, _))
+      .Times(1);
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(
+          metrics::kMetricSuccessfulUpdateAttemptCount, attempt_count, _, _, _))
+      .Times(1);
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendToUMA(metrics::kMetricSuccessfulUpdateUpdatesAbandonedCount,
+                        updates_abandoned_count,
+                        _,
+                        _,
+                        _))
+      .Times(1);
+
+  reporter_.ReportSuccessfulUpdateMetrics(attempt_count,
+                                          updates_abandoned_count,
+                                          payload_type,
+                                          payload_size,
+                                          num_bytes_downloaded,
+                                          download_overhead_percentage,
+                                          total_duration,
+                                          reboot_count,
+                                          url_switch_count);
+}
+
+TEST_F(MetricsReporterOmahaTest, ReportRollbackMetrics) {
+  metrics::RollbackResult result = metrics::RollbackResult::kSuccess;
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendEnumToUMA(
+                  metrics::kMetricRollbackResult, static_cast<int>(result), _))
+      .Times(1);
+
+  reporter_.ReportRollbackMetrics(result);
+}
+
+TEST_F(MetricsReporterOmahaTest, ReportCertificateCheckMetrics) {
+  ServerToCheck server_to_check = ServerToCheck::kUpdate;
+  CertificateCheckResult result = CertificateCheckResult::kValid;
+  EXPECT_CALL(*mock_metrics_lib_,
+              SendEnumToUMA(metrics::kMetricCertificateCheckUpdateCheck,
+                            static_cast<int>(result),
+                            _))
+      .Times(1);
+
+  reporter_.ReportCertificateCheckMetrics(server_to_check, result);
+}
+
+TEST_F(MetricsReporterOmahaTest, ReportFailedUpdateCount) {
+  int target_attempt = 3;
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(metrics::kMetricFailedUpdateCount, target_attempt, _, _, _))
+      .Times(1);
+
+  reporter_.ReportFailedUpdateCount(target_attempt);
+}
+
+TEST_F(MetricsReporterOmahaTest, ReportTimeToReboot) {
+  int time_to_reboot_minutes = 1000;
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendToUMA(
+          metrics::kMetricTimeToRebootMinutes, time_to_reboot_minutes, _, _, _))
+      .Times(1);
+
+  reporter_.ReportTimeToReboot(time_to_reboot_minutes);
+}
+
+TEST_F(MetricsReporterOmahaTest, ReportInstallDateProvisioningSource) {
+  int source = 2;
+  int max = 5;
+  EXPECT_CALL(
+      *mock_metrics_lib_,
+      SendEnumToUMA(metrics::kMetricInstallDateProvisioningSource, source, max))
+      .Times(1);
+
+  reporter_.ReportInstallDateProvisioningSource(source, max);
+}
+
+}  // namespace chromeos_update_engine
diff --git a/metrics_reporter_stub.cc b/metrics_reporter_stub.cc
new file mode 100644
index 0000000..81664a5
--- /dev/null
+++ b/metrics_reporter_stub.cc
@@ -0,0 +1,31 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/metrics_reporter_stub.h"
+
+#include <memory>
+
+namespace chromeos_update_engine {
+
+namespace metrics {
+
+std::unique_ptr<MetricsReporterInterface> CreateMetricsReporter() {
+  return std::make_unique<MetricsReporterStub>();
+}
+
+}  // namespace metrics
+
+}  // namespace chromeos_update_engine
diff --git a/metrics_reporter_stub.h b/metrics_reporter_stub.h
new file mode 100644
index 0000000..d0f75ab
--- /dev/null
+++ b/metrics_reporter_stub.h
@@ -0,0 +1,88 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_METRICS_REPORTER_STUB_H_
+#define UPDATE_ENGINE_METRICS_REPORTER_STUB_H_
+
+#include "update_engine/common/error_code.h"
+#include "update_engine/metrics_constants.h"
+#include "update_engine/metrics_reporter_interface.h"
+
+namespace chromeos_update_engine {
+
+class MetricsReporterStub : public MetricsReporterInterface {
+ public:
+  MetricsReporterStub() = default;
+
+  ~MetricsReporterStub() override = default;
+
+  void Initialize() override {}
+
+  void ReportRollbackMetrics(metrics::RollbackResult result) override {}
+
+  void ReportDailyMetrics(base::TimeDelta os_age) override {}
+
+  void ReportUpdateCheckMetrics(
+      SystemState* system_state,
+      metrics::CheckResult result,
+      metrics::CheckReaction reaction,
+      metrics::DownloadErrorCode download_error_code) override {}
+
+  void ReportUpdateAttemptMetrics(SystemState* system_state,
+                                  int attempt_number,
+                                  PayloadType payload_type,
+                                  base::TimeDelta duration,
+                                  base::TimeDelta duration_uptime,
+                                  int64_t payload_size,
+                                  metrics::AttemptResult attempt_result,
+                                  ErrorCode internal_error_code) override {}
+
+  void ReportUpdateAttemptDownloadMetrics(
+      int64_t payload_bytes_downloaded,
+      int64_t payload_download_speed_bps,
+      DownloadSource download_source,
+      metrics::DownloadErrorCode payload_download_error_code,
+      metrics::ConnectionType connection_type) override {}
+
+  void ReportAbnormallyTerminatedUpdateAttemptMetrics() override {}
+
+  void ReportSuccessfulUpdateMetrics(
+      int attempt_count,
+      int updates_abandoned_count,
+      PayloadType payload_type,
+      int64_t payload_size,
+      int64_t num_bytes_downloaded[kNumDownloadSources],
+      int download_overhead_percentage,
+      base::TimeDelta total_duration,
+      int reboot_count,
+      int url_switch_count) override {}
+
+  void ReportCertificateCheckMetrics(ServerToCheck server_to_check,
+                                     CertificateCheckResult result) override {}
+
+  void ReportFailedUpdateCount(int target_attempt) override {}
+
+  void ReportTimeToReboot(int time_to_reboot_minutes) override {}
+
+  void ReportInstallDateProvisioningSource(int source, int max) override {}
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(MetricsReporterStub);
+};
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_METRICS_REPORTER_STUB_H_
diff --git a/metrics_utils.cc b/metrics_utils.cc
index 425dc4d..46530f0 100644
--- a/metrics_utils.cc
+++ b/metrics_utils.cc
@@ -21,7 +21,8 @@
 #include <base/time/time.h>
 
 #include "update_engine/common/clock_interface.h"
-#include "update_engine/common/prefs_interface.h"
+#include "update_engine/common/constants.h"
+#include "update_engine/common/utils.h"
 #include "update_engine/system_state.h"
 
 using base::Time;
@@ -38,6 +39,9 @@
     case ErrorCode::kSuccess:
       return metrics::AttemptResult::kUpdateSucceeded;
 
+    case ErrorCode::kUpdatedButNotActive:
+      return metrics::AttemptResult::kUpdateSucceededNotActive;
+
     case ErrorCode::kDownloadTransferError:
       return metrics::AttemptResult::kPayloadDownloadError;
 
@@ -211,6 +215,7 @@
     case ErrorCode::kFilesystemVerifierError:
     case ErrorCode::kUserCanceled:
     case ErrorCode::kPayloadTimestampError:
+    case ErrorCode::kUpdatedButNotActive:
       break;
 
     // Special flags. These can't happen (we mask them out above) but
@@ -307,5 +312,76 @@
   return ret;
 }
 
+int64_t GetPersistedValue(const std::string& key, PrefsInterface* prefs) {
+  CHECK(prefs);
+  if (!prefs->Exists(key))
+    return 0;
+
+  int64_t stored_value;
+  if (!prefs->GetInt64(key, &stored_value))
+    return 0;
+
+  if (stored_value < 0) {
+    LOG(ERROR) << key << ": Invalid value (" << stored_value
+               << ") in persisted state. Defaulting to 0";
+    return 0;
+  }
+
+  return stored_value;
+}
+
+void SetNumReboots(int64_t num_reboots, PrefsInterface* prefs) {
+  CHECK(prefs);
+  prefs->SetInt64(kPrefsNumReboots, num_reboots);
+  LOG(INFO) << "Number of Reboots during current update attempt = "
+            << num_reboots;
+}
+
+void SetPayloadAttemptNumber(int64_t payload_attempt_number,
+                             PrefsInterface* prefs) {
+  CHECK(prefs);
+  prefs->SetInt64(kPrefsPayloadAttemptNumber, payload_attempt_number);
+  LOG(INFO) << "Payload Attempt Number = " << payload_attempt_number;
+}
+
+void SetSystemUpdatedMarker(ClockInterface* clock, PrefsInterface* prefs) {
+  CHECK(prefs);
+  CHECK(clock);
+  Time update_finish_time = clock->GetMonotonicTime();
+  prefs->SetInt64(kPrefsSystemUpdatedMarker,
+                  update_finish_time.ToInternalValue());
+  LOG(INFO) << "Updated Marker = " << utils::ToString(update_finish_time);
+}
+
+void SetUpdateTimestampStart(const Time& update_start_time,
+                             PrefsInterface* prefs) {
+  CHECK(prefs);
+  prefs->SetInt64(kPrefsUpdateTimestampStart,
+                  update_start_time.ToInternalValue());
+  LOG(INFO) << "Update Timestamp Start = "
+            << utils::ToString(update_start_time);
+}
+
+bool LoadAndReportTimeToReboot(MetricsReporterInterface* metrics_reporter,
+                               PrefsInterface* prefs,
+                               ClockInterface* clock) {
+  CHECK(prefs);
+  CHECK(clock);
+  int64_t stored_value = GetPersistedValue(kPrefsSystemUpdatedMarker, prefs);
+  if (stored_value == 0)
+    return false;
+
+  Time system_updated_at = Time::FromInternalValue(stored_value);
+  base::TimeDelta time_to_reboot =
+      clock->GetMonotonicTime() - system_updated_at;
+  if (time_to_reboot.ToInternalValue() < 0) {
+    LOG(ERROR) << "time_to_reboot is negative - system_updated_at: "
+               << utils::ToString(system_updated_at);
+    return false;
+  }
+  metrics_reporter->ReportTimeToReboot(time_to_reboot.InMinutes());
+  return true;
+}
+
 }  // namespace metrics_utils
 }  // namespace chromeos_update_engine
diff --git a/metrics_utils.h b/metrics_utils.h
index d9826c1..d08cc4a 100644
--- a/metrics_utils.h
+++ b/metrics_utils.h
@@ -17,8 +17,16 @@
 #ifndef UPDATE_ENGINE_METRICS_UTILS_H_
 #define UPDATE_ENGINE_METRICS_UTILS_H_
 
+#include <string>
+
+#include <base/time/time.h>
+
+#include "update_engine/common/clock_interface.h"
+#include "update_engine/common/error_code.h"
+#include "update_engine/common/prefs_interface.h"
 #include "update_engine/connection_utils.h"
-#include "update_engine/metrics.h"
+#include "update_engine/metrics_constants.h"
+#include "update_engine/metrics_reporter_interface.h"
 
 namespace chromeos_update_engine {
 
@@ -65,6 +73,33 @@
                              int64_t* storage,
                              base::TimeDelta* out_duration);
 
+// Returns the persisted value from prefs for the given key. It also
+// validates that the value returned is non-negative.
+int64_t GetPersistedValue(const std::string& key, PrefsInterface* prefs);
+
+// Persists the reboot count of the update attempt to |kPrefsNumReboots|.
+void SetNumReboots(int64_t num_reboots, PrefsInterface* prefs);
+
+// Persists the payload attempt number to |kPrefsPayloadAttemptNumber|.
+void SetPayloadAttemptNumber(int64_t payload_attempt_number,
+                             PrefsInterface* prefs);
+
+// Persists the finished time of an update to the |kPrefsSystemUpdatedMarker|.
+void SetSystemUpdatedMarker(ClockInterface* clock, PrefsInterface* prefs);
+
+// Persists the start time of an update to |kPrefsUpdateTimestampStart|.
+void SetUpdateTimestampStart(const base::Time& update_start_time,
+                             PrefsInterface* prefs);
+
+// Called at program startup if the device booted into a new update.
+// The |time_to_reboot| parameter contains the (monotonic-clock) duration
+// from when the update successfully completed (the value in
+// |kPrefsSystemUpdatedMarker|) until the device was booted into the update
+// (current monotonic-clock time).
+bool LoadAndReportTimeToReboot(MetricsReporterInterface* metrics_reporter,
+                               PrefsInterface* prefs,
+                               ClockInterface* clock);
+
 }  // namespace metrics_utils
 }  // namespace chromeos_update_engine
 
diff --git a/mock_file_writer.h b/mock_file_writer.h
index 72d6a86..26cd45d 100644
--- a/mock_file_writer.h
+++ b/mock_file_writer.h
@@ -24,7 +24,8 @@
 
 class MockFileWriter : public FileWriter {
  public:
-  MOCK_METHOD2(Write, ssize_t(const void* bytes, size_t count));
+  MOCK_METHOD2(Write, bool(const void* bytes, size_t count));
+  MOCK_METHOD3(Write, bool(const void* bytes, size_t count, ErrorCode* error));
   MOCK_METHOD0(Close, int());
 };
 
diff --git a/mock_metrics_reporter.h b/mock_metrics_reporter.h
new file mode 100644
index 0000000..a0f164b
--- /dev/null
+++ b/mock_metrics_reporter.h
@@ -0,0 +1,83 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_MOCK_METRICS_REPORTER_H
+#define UPDATE_ENGINE_MOCK_METRICS_REPORTER_H
+
+#include <gmock/gmock.h>
+
+#include "update_engine/metrics_reporter_interface.h"
+
+namespace chromeos_update_engine {
+
+class MockMetricsReporter : public MetricsReporterInterface {
+ public:
+  MOCK_METHOD0(Initialize, void());
+
+  MOCK_METHOD1(ReportRollbackMetrics, void(metrics::RollbackResult result));
+
+  MOCK_METHOD1(ReportDailyMetrics, void(base::TimeDelta os_age));
+
+  MOCK_METHOD4(ReportUpdateCheckMetrics,
+               void(SystemState* system_state,
+                    metrics::CheckResult result,
+                    metrics::CheckReaction reaction,
+                    metrics::DownloadErrorCode download_error_code));
+
+  MOCK_METHOD8(ReportUpdateAttemptMetrics,
+               void(SystemState* system_state,
+                    int attempt_number,
+                    PayloadType payload_type,
+                    base::TimeDelta duration,
+                    base::TimeDelta duration_uptime,
+                    int64_t payload_size,
+                    metrics::AttemptResult attempt_result,
+                    ErrorCode internal_error_code));
+
+  MOCK_METHOD5(ReportUpdateAttemptDownloadMetrics,
+               void(int64_t payload_bytes_downloaded,
+                    int64_t payload_download_speed_bps,
+                    DownloadSource download_source,
+                    metrics::DownloadErrorCode payload_download_error_code,
+                    metrics::ConnectionType connection_type));
+
+  MOCK_METHOD0(ReportAbnormallyTerminatedUpdateAttemptMetrics, void());
+
+  MOCK_METHOD9(ReportSuccessfulUpdateMetrics,
+               void(int attempt_count,
+                    int updates_abandoned_count,
+                    PayloadType payload_type,
+                    int64_t payload_size,
+                    int64_t num_bytes_downloaded[kNumDownloadSources],
+                    int download_overhead_percentage,
+                    base::TimeDelta total_duration,
+                    int reboot_count,
+                    int url_switch_count));
+
+  MOCK_METHOD2(ReportCertificateCheckMetrics,
+               void(ServerToCheck server_to_check,
+                    CertificateCheckResult result));
+
+  MOCK_METHOD1(ReportFailedUpdateCount, void(int target_attempt));
+
+  MOCK_METHOD1(ReportTimeToReboot, void(int time_to_reboot_minutes));
+
+  MOCK_METHOD2(ReportInstallDateProvisioningSource, void(int source, int max));
+};
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_MOCK_METRICS_REPORTER_H
diff --git a/mock_service_observer.h b/mock_service_observer.h
new file mode 100644
index 0000000..e434eab
--- /dev/null
+++ b/mock_service_observer.h
@@ -0,0 +1,35 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_MOCK_SERVICE_OBSERVER_H_
+#define UPDATE_ENGINE_MOCK_SERVICE_OBSERVER_H_
+
+#include <gmock/gmock.h>
+#include "update_engine/service_observer_interface.h"
+
+namespace chromeos_update_engine {
+
+class MockServiceObserver : public ServiceObserverInterface {
+ public:
+  MOCK_METHOD1(
+      SendStatusUpdate,
+      void(const update_engine::UpdateEngineStatus& update_engine_status));
+  MOCK_METHOD1(SendPayloadApplicationComplete, void(ErrorCode error_code));
+};
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_MOCK_SERVICE_OBSERVER_H_
diff --git a/mock_update_attempter.h b/mock_update_attempter.h
index 89f163e..d88b840 100644
--- a/mock_update_attempter.h
+++ b/mock_update_attempter.h
@@ -36,19 +36,18 @@
                             bool obey_proxies,
                             bool interactive));
 
-  MOCK_METHOD5(GetStatus, bool(int64_t* last_checked_time,
-                               double* progress,
-                               std::string* current_operation,
-                               std::string* new_version,
-                               int64_t* new_size));
+  MOCK_METHOD1(GetStatus, bool(update_engine::UpdateEngineStatus* out_status));
 
   MOCK_METHOD1(GetBootTimeAtUpdate, bool(base::Time* out_boot_time));
 
   MOCK_METHOD0(ResetStatus, bool(void));
 
-  MOCK_METHOD3(CheckForUpdate, void(const std::string& app_version,
-                                    const std::string& omaha_url,
-                                    bool is_interactive));
+  MOCK_METHOD0(GetCurrentUpdateAttemptFlags, UpdateAttemptFlags(void));
+
+  MOCK_METHOD3(CheckForUpdate,
+               bool(const std::string& app_version,
+                    const std::string& omaha_url,
+                    UpdateAttemptFlags flags));
 
   MOCK_METHOD0(RefreshDevicePolicy, void(void));
 
diff --git a/network_selector_android.cc b/network_selector_android.cc
index 6879b69..55ba799 100644
--- a/network_selector_android.cc
+++ b/network_selector_android.cc
@@ -16,9 +16,10 @@
 
 #include "update_engine/network_selector_android.h"
 
+#include <memory>
+
 #include <android/multinetwork.h>
 #include <base/logging.h>
-#include <brillo/make_unique_ptr.h>
 
 namespace chromeos_update_engine {
 
@@ -26,7 +27,7 @@
 
 // Factory defined in network_selector.h.
 std::unique_ptr<NetworkSelectorInterface> CreateNetworkSelector() {
-  return brillo::make_unique_ptr(new NetworkSelectorAndroid());
+  return std::make_unique<NetworkSelectorAndroid>();
 }
 
 }  // namespace network
diff --git a/network_selector_stub.cc b/network_selector_stub.cc
index 218d454..67925f4 100644
--- a/network_selector_stub.cc
+++ b/network_selector_stub.cc
@@ -16,8 +16,9 @@
 
 #include "update_engine/network_selector_stub.h"
 
+#include <memory>
+
 #include <base/logging.h>
-#include <brillo/make_unique_ptr.h>
 
 namespace chromeos_update_engine {
 
@@ -25,7 +26,7 @@
 
 // Factory defined in network_selector.h.
 std::unique_ptr<NetworkSelectorInterface> CreateNetworkSelector() {
-  return brillo::make_unique_ptr(new NetworkSelectorStub());
+  return std::make_unique<NetworkSelectorStub>();
 }
 
 }  // namespace network
diff --git a/omaha_request_action.cc b/omaha_request_action.cc
index c3bbf9d..c4db0c7 100644
--- a/omaha_request_action.cc
+++ b/omaha_request_action.cc
@@ -31,6 +31,7 @@
 #include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
 #include <base/time/time.h>
+#include <brillo/key_value_store.h>
 #include <expat.h>
 #include <metrics/metrics_library.h>
 
@@ -42,7 +43,7 @@
 #include "update_engine/common/prefs_interface.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/connection_manager_interface.h"
-#include "update_engine/metrics.h"
+#include "update_engine/metrics_reporter_interface.h"
 #include "update_engine/metrics_utils.h"
 #include "update_engine/omaha_request_params.h"
 #include "update_engine/p2p_manager.h"
@@ -207,8 +208,17 @@
 struct OmahaAppData {
   string id;
   string version;
+  string product_components;
 };
 
+bool IsValidComponentID(const string& id) {
+  for (char c : id) {
+    if (!isalnum(c) && c != '-' && c != '_' && c != '.')
+      return false;
+  }
+  return true;
+}
+
 // Returns an XML that corresponds to the entire <app> node of the Omaha
 // request based on the given parameters.
 string GetAppXml(const OmahaEvent* event,
@@ -276,11 +286,39 @@
                     XmlEncodeWithDefault(params->os_build_type(), "") + "\" ";
   }
 
+  string product_components_args;
+  if (!app_data.product_components.empty()) {
+    brillo::KeyValueStore store;
+    if (store.LoadFromString(app_data.product_components)) {
+      for (const string& key : store.GetKeys()) {
+        if (!IsValidComponentID(key)) {
+          LOG(ERROR) << "Invalid component id: " << key;
+          continue;
+        }
+        string version;
+        if (!store.GetString(key, &version)) {
+          LOG(ERROR) << "Failed to get version for " << key
+                     << " in product_components.";
+          continue;
+        }
+        product_components_args +=
+            base::StringPrintf("_%s.version=\"%s\" ",
+                               key.c_str(),
+                               XmlEncodeWithDefault(version, "").c_str());
+      }
+    } else {
+      LOG(ERROR) << "Failed to parse product_components:\n"
+                 << app_data.product_components;
+    }
+  }
+
+  // clang-format off
   string app_xml = "    <app "
       "appid=\"" + XmlEncodeWithDefault(app_data.id, "") + "\" " +
       app_cohort_args +
       app_versions +
       app_channels +
+      product_components_args +
       fingerprint_arg +
       buildtype_arg +
       "lang=\"" + XmlEncodeWithDefault(params->app_lang(), "en-US") + "\" " +
@@ -293,7 +331,7 @@
       ">\n" +
          app_body +
       "    </app>\n";
-
+  // clang-format on
   return app_xml;
 }
 
@@ -319,8 +357,10 @@
                      int install_date_in_days,
                      SystemState* system_state) {
   string os_xml = GetOsXml(params);
-  OmahaAppData product_app = {.id = params->GetAppId(),
-                              .version = params->app_version()};
+  OmahaAppData product_app = {
+      .id = params->GetAppId(),
+      .version = params->app_version(),
+      .product_components = params->product_components()};
   string app_xml = GetAppXml(event,
                              params,
                              product_app,
@@ -380,22 +420,23 @@
   string current_path;
 
   // These are the values extracted from the XML.
-  string app_cohort;
-  string app_cohorthint;
-  string app_cohortname;
-  bool app_cohort_set = false;
-  bool app_cohorthint_set = false;
-  bool app_cohortname_set = false;
   string updatecheck_poll_interval;
   map<string, string> updatecheck_attrs;
   string daystart_elapsed_days;
   string daystart_elapsed_seconds;
 
   struct App {
+    string id;
     vector<string> url_codebase;
     string manifest_version;
     map<string, string> action_postinstall_attrs;
     string updatecheck_status;
+    string cohort;
+    string cohorthint;
+    string cohortname;
+    bool cohort_set = false;
+    bool cohorthint_set = false;
+    bool cohortname_set = false;
 
     struct Package {
       string name;
@@ -429,19 +470,23 @@
   }
 
   if (data->current_path == "/response/app") {
-    data->apps.emplace_back();
+    OmahaParserData::App app;
+    if (attrs.find("appid") != attrs.end()) {
+      app.id = attrs["appid"];
+    }
     if (attrs.find("cohort") != attrs.end()) {
-      data->app_cohort_set = true;
-      data->app_cohort = attrs["cohort"];
+      app.cohort_set = true;
+      app.cohort = attrs["cohort"];
     }
     if (attrs.find("cohorthint") != attrs.end()) {
-      data->app_cohorthint_set = true;
-      data->app_cohorthint = attrs["cohorthint"];
+      app.cohorthint_set = true;
+      app.cohorthint = attrs["cohorthint"];
     }
     if (attrs.find("cohortname") != attrs.end()) {
-      data->app_cohortname_set = true;
-      data->app_cohortname = attrs["cohortname"];
+      app.cohortname_set = true;
+      app.cohortname = attrs["cohortname"];
     }
+    data->apps.push_back(std::move(app));
   } else if (data->current_path == "/response/app/updatecheck") {
     if (!data->apps.empty())
       data->apps.back().updatecheck_status = attrs["status"];
@@ -623,6 +668,11 @@
                 << "powerwash_count is " << powerwash_count;
       return false;
     }
+    if (system_state_->hardware()->GetFirstActiveOmahaPingSent()) {
+      LOG(INFO) << "Not sending ping with a=-1 r=-1 to omaha because "
+                << "the first_active_omaha_ping_sent is true";
+      return false;
+    }
     return true;
   }
   return ping_active_days_ > 0 || ping_roll_call_days_ > 0;
@@ -919,12 +969,17 @@
   }
 
   // We persist the cohorts sent by omaha even if the status is "noupdate".
-  if (parser_data->app_cohort_set)
-    PersistCohortData(kPrefsOmahaCohort, parser_data->app_cohort);
-  if (parser_data->app_cohorthint_set)
-    PersistCohortData(kPrefsOmahaCohortHint, parser_data->app_cohorthint);
-  if (parser_data->app_cohortname_set)
-    PersistCohortData(kPrefsOmahaCohortName, parser_data->app_cohortname);
+  for (const auto& app : parser_data->apps) {
+    if (app.id == params_->GetAppId()) {
+      if (app.cohort_set)
+        PersistCohortData(kPrefsOmahaCohort, app.cohort);
+      if (app.cohorthint_set)
+        PersistCohortData(kPrefsOmahaCohortHint, app.cohorthint);
+      if (app.cohortname_set)
+        PersistCohortData(kPrefsOmahaCohortName, app.cohortname);
+      break;
+    }
+  }
 
   // Parse the updatecheck attributes.
   PersistEolStatus(parser_data->updatecheck_attrs);
@@ -983,10 +1038,18 @@
                                      ScopedActionCompleter* completer) {
   map<string, string> attrs;
   for (auto& app : parser_data->apps) {
-    if (!app.manifest_version.empty() && output_object->version.empty())
+    if (app.id == params_->GetAppId()) {
+      // this is the app (potentially the only app)
       output_object->version = app.manifest_version;
-    if (!app.action_postinstall_attrs.empty() && attrs.empty())
+    } else if (!params_->system_app_id().empty() &&
+               app.id == params_->system_app_id()) {
+      // this is the system app (this check is intentionally skipped if there is
+      // no system_app_id set)
+      output_object->system_version = app.manifest_version;
+    }
+    if (!app.action_postinstall_attrs.empty() && attrs.empty()) {
       attrs = app.action_postinstall_attrs;
+    }
   }
   if (output_object->version.empty()) {
     LOG(ERROR) << "Omaha Response does not have version in manifest!";
@@ -1087,6 +1150,16 @@
   LOG_IF(ERROR, !UpdateLastPingDays(&parser_data, system_state_->prefs()))
       << "Failed to update the last ping day preferences!";
 
+  // Sets first_active_omaha_ping_sent to true (vpd in CrOS). We only do this if
+  // we have got a response from omaha and if its value has never been set to
+  // true before. Failure of this function should be ignored. There should be no
+  // need to check if a=-1 has been sent because older devices have already sent
+  // their a=-1 in the past and we have to set first_active_omaha_ping_sent for
+  // future checks.
+  if (!system_state_->hardware()->GetFirstActiveOmahaPingSent()) {
+    system_state_->hardware()->SetFirstActiveOmahaPingSent();
+  }
+
   if (!HasOutputPipe()) {
     // Just set success to whether or not the http transfer succeeded,
     // which must be true at this point in the code.
@@ -1503,12 +1576,9 @@
   if (!prefs->SetInt64(kPrefsInstallDateDays, install_date_days))
     return false;
 
-  string metric_name = metrics::kMetricInstallDateProvisioningSource;
-  system_state->metrics_lib()->SendEnumToUMA(
-      metric_name,
+  system_state->metrics_reporter()->ReportInstallDateProvisioningSource(
       static_cast<int>(source),  // Sample.
       kProvisionedMax);          // Maximum.
-
   return true;
 }
 
@@ -1594,8 +1664,8 @@
     break;
   }
 
-  metrics::ReportUpdateCheckMetrics(system_state_,
-                                    result, reaction, download_error_code);
+  system_state_->metrics_reporter()->ReportUpdateCheckMetrics(
+      system_state_, result, reaction, download_error_code);
 }
 
 bool OmahaRequestAction::ShouldIgnoreUpdate(
diff --git a/omaha_request_action_unittest.cc b/omaha_request_action_unittest.cc
index 9091031..d57abe5 100644
--- a/omaha_request_action_unittest.cc
+++ b/omaha_request_action_unittest.cc
@@ -18,18 +18,19 @@
 
 #include <stdint.h>
 
+#include <memory>
 #include <string>
 #include <vector>
 
 #include <base/bind.h>
 #include <base/files/file_util.h>
 #include <base/files/scoped_temp_dir.h>
+#include <base/memory/ptr_util.h>
 #include <base/strings/string_number_conversions.h>
 #include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
 #include <base/time/time.h>
 #include <brillo/bind_lambda.h>
-#include <brillo/make_unique_ptr.h>
 #include <brillo/message_loops/fake_message_loop.h>
 #include <brillo/message_loops/message_loop.h>
 #include <brillo/message_loops/message_loop_utils.h>
@@ -44,7 +45,7 @@
 #include "update_engine/common/prefs.h"
 #include "update_engine/common/test_utils.h"
 #include "update_engine/fake_system_state.h"
-#include "update_engine/metrics.h"
+#include "update_engine/metrics_reporter_interface.h"
 #include "update_engine/mock_connection_manager.h"
 #include "update_engine/mock_payload_state.h"
 #include "update_engine/omaha_request_params.h"
@@ -62,12 +63,13 @@
 using testing::Return;
 using testing::ReturnPointee;
 using testing::SaveArg;
-using testing::SetArgumentPointee;
+using testing::SetArgPointee;
 using testing::_;
 
 namespace {
 
 const char kTestAppId[] = "test-app-id";
+const char kTestAppId2[] = "test-app2-id";
 
 // This is a helper struct to allow unit tests build an update response with the
 // values they care about.
@@ -89,7 +91,8 @@
            "<ping status=\"ok\"/>"
            "<updatecheck status=\"noupdate\"/></app>" +
            (multi_app_no_update
-                ? "<app><updatecheck status=\"noupdate\"/></app>"
+                ? "<app appid=\"" + app_id2 +
+                      "\"><updatecheck status=\"noupdate\"/></app>"
                 : "") +
            "</response>";
   }
@@ -142,9 +145,11 @@
            (disable_p2p_for_sharing ? "DisableP2PForSharing=\"true\" " : "") +
            "/></actions></manifest></updatecheck></app>" +
            (multi_app
-                ? "<app><updatecheck status=\"ok\"><urls><url codebase=\"" +
-                      codebase2 +
-                      "\"/></urls><manifest><packages>"
+                ? "<app appid=\"" + app_id2 + "\"" +
+                      (include_cohorts ? " cohort=\"cohort2\"" : "") +
+                      "><updatecheck status=\"ok\"><urls><url codebase=\"" +
+                      codebase2 + "\"/></urls><manifest version=\"" + version2 +
+                      "\"><packages>"
                       "<package name=\"package3\" size=\"333\" "
                       "hash_sha256=\"hash3\"/></packages>"
                       "<actions><action event=\"postinstall\" " +
@@ -166,7 +171,9 @@
   }
 
   string app_id = kTestAppId;
+  string app_id2 = kTestAppId2;
   string version = "1.2.3.4";
+  string version2 = "2.3.4.5";
   string more_info_url = "http://more/info";
   string prompt = "true";
   string codebase = "http://code/base/";
@@ -372,7 +379,7 @@
     fake_system_state_.set_request_params(request_params);
   OmahaRequestAction action(&fake_system_state_,
                             nullptr,
-                            brillo::make_unique_ptr(fetcher),
+                            base::WrapUnique(fetcher),
                             ping_only);
   OmahaRequestActionTestProcessorDelegate delegate;
   delegate.expected_code_ = expected_code;
@@ -385,23 +392,16 @@
   BondActions(&action, &collector_action);
   processor.EnqueueAction(&collector_action);
 
-  EXPECT_CALL(*fake_system_state_.mock_metrics_lib(), SendEnumToUMA(_, _, _))
+  EXPECT_CALL(*fake_system_state_.mock_metrics_reporter(),
+              ReportUpdateCheckMetrics(_, _, _, _))
       .Times(AnyNumber());
-  EXPECT_CALL(*fake_system_state_.mock_metrics_lib(),
-      SendEnumToUMA(metrics::kMetricCheckResult,
-          static_cast<int>(expected_check_result),
-          static_cast<int>(metrics::CheckResult::kNumConstants) - 1))
-      .Times(expected_check_result == metrics::CheckResult::kUnset ? 0 : 1);
-  EXPECT_CALL(*fake_system_state_.mock_metrics_lib(),
-      SendEnumToUMA(metrics::kMetricCheckReaction,
-          static_cast<int>(expected_check_reaction),
-          static_cast<int>(metrics::CheckReaction::kNumConstants) - 1))
-      .Times(expected_check_reaction == metrics::CheckReaction::kUnset ? 0 : 1);
-  EXPECT_CALL(*fake_system_state_.mock_metrics_lib(),
-      SendSparseToUMA(metrics::kMetricCheckDownloadErrorCode,
-          static_cast<int>(expected_download_error_code)))
-      .Times(expected_download_error_code == metrics::DownloadErrorCode::kUnset
-             ? 0 : 1);
+
+  EXPECT_CALL(*fake_system_state_.mock_metrics_reporter(),
+              ReportUpdateCheckMetrics(_,
+                                       expected_check_result,
+                                       expected_check_reaction,
+                                       expected_download_error_code))
+      .Times(ping_only ? 0 : 1);
 
   loop.PostTask(base::Bind(
       [](ActionProcessor* processor) { processor->StartProcessing(); },
@@ -431,7 +431,7 @@
   fake_system_state.set_request_params(&params);
   OmahaRequestAction action(&fake_system_state,
                             event,
-                            brillo::make_unique_ptr(fetcher),
+                            base::WrapUnique(fetcher),
                             false);
   OmahaRequestActionTestProcessorDelegate delegate;
   ActionProcessor processor;
@@ -549,6 +549,7 @@
                       nullptr));
   EXPECT_TRUE(response.update_exists);
   EXPECT_EQ(fake_update_response_.version, response.version);
+  EXPECT_EQ("", response.system_version);
   EXPECT_EQ(fake_update_response_.GetPayloadUrl(),
             response.packages[0].payload_urls[0]);
   EXPECT_EQ(fake_update_response_.more_info_url, response.more_info_url);
@@ -557,7 +558,7 @@
   EXPECT_EQ(true, response.packages[0].is_delta);
   EXPECT_EQ(fake_update_response_.prompt == "true", response.prompt);
   EXPECT_EQ(fake_update_response_.deadline, response.deadline);
-  // Omaha cohort attribets are not set in the response, so they should not be
+  // Omaha cohort attributes are not set in the response, so they should not be
   // persisted.
   EXPECT_FALSE(fake_prefs_.Exists(kPrefsOmahaCohort));
   EXPECT_FALSE(fake_prefs_.Exists(kPrefsOmahaCohortHint));
@@ -624,6 +625,40 @@
   EXPECT_EQ(false, response.packages[1].is_delta);
 }
 
+TEST_F(OmahaRequestActionTest, MultiAppAndSystemUpdateTest) {
+  OmahaResponse response;
+  fake_update_response_.multi_app = true;
+  // trigger the lining up of the app and system versions
+  request_params_.set_system_app_id(fake_update_response_.app_id2);
+
+  ASSERT_TRUE(TestUpdateCheck(nullptr,  // request_params
+                              fake_update_response_.GetUpdateResponse(),
+                              -1,
+                              false,  // ping_only
+                              ErrorCode::kSuccess,
+                              metrics::CheckResult::kUpdateAvailable,
+                              metrics::CheckReaction::kUpdating,
+                              metrics::DownloadErrorCode::kUnset,
+                              &response,
+                              nullptr));
+  EXPECT_TRUE(response.update_exists);
+  EXPECT_EQ(fake_update_response_.version, response.version);
+  EXPECT_EQ(fake_update_response_.version2, response.system_version);
+  EXPECT_EQ(fake_update_response_.GetPayloadUrl(),
+            response.packages[0].payload_urls[0]);
+  EXPECT_EQ(fake_update_response_.codebase2 + "package3",
+            response.packages[1].payload_urls[0]);
+  EXPECT_EQ(fake_update_response_.hash, response.packages[0].hash);
+  EXPECT_EQ(fake_update_response_.size, response.packages[0].size);
+  EXPECT_EQ(11u, response.packages[0].metadata_size);
+  EXPECT_EQ(true, response.packages[0].is_delta);
+  ASSERT_EQ(2u, response.packages.size());
+  EXPECT_EQ(string("hash3"), response.packages[1].hash);
+  EXPECT_EQ(333u, response.packages[1].size);
+  EXPECT_EQ(33u, response.packages[1].metadata_size);
+  EXPECT_EQ(false, response.packages[1].is_delta);
+}
+
 TEST_F(OmahaRequestActionTest, MultiAppPartialUpdateTest) {
   OmahaResponse response;
   fake_update_response_.multi_app = true;
@@ -640,6 +675,7 @@
                               nullptr));
   EXPECT_TRUE(response.update_exists);
   EXPECT_EQ(fake_update_response_.version, response.version);
+  EXPECT_EQ("", response.system_version);
   EXPECT_EQ(fake_update_response_.GetPayloadUrl(),
             response.packages[0].payload_urls[0]);
   EXPECT_EQ(fake_update_response_.hash, response.packages[0].hash);
@@ -668,6 +704,7 @@
                               nullptr));
   EXPECT_TRUE(response.update_exists);
   EXPECT_EQ(fake_update_response_.version, response.version);
+  EXPECT_EQ("", response.system_version);
   EXPECT_EQ(fake_update_response_.GetPayloadUrl(),
             response.packages[0].payload_urls[0]);
   EXPECT_EQ(fake_update_response_.codebase + "package2",
@@ -698,8 +735,8 @@
 
   MockHttpFetcher* fetcher =
       new MockHttpFetcher(http_response.data(), http_response.size(), nullptr);
-  OmahaRequestAction action(
-      &fake_system_state_, nullptr, brillo::make_unique_ptr(fetcher), false);
+  OmahaRequestAction action(&fake_system_state_, nullptr,
+                            base::WrapUnique(fetcher), false);
   ActionProcessor processor;
   processor.EnqueueAction(&action);
 
@@ -725,8 +762,8 @@
 
   EXPECT_CALL(mock_cm, GetConnectionProperties(_, _))
       .WillRepeatedly(
-          DoAll(SetArgumentPointee<0>(ConnectionType::kEthernet),
-                SetArgumentPointee<1>(ConnectionTethering::kUnknown),
+          DoAll(SetArgPointee<0>(ConnectionType::kEthernet),
+                SetArgPointee<1>(ConnectionTethering::kUnknown),
                 Return(true)));
   EXPECT_CALL(mock_cm, IsUpdateAllowedOver(ConnectionType::kEthernet, _))
       .WillRepeatedly(Return(false));
@@ -775,18 +812,19 @@
 TEST_F(OmahaRequestActionTest, SkipNonCriticalUpdatesBeforeOOBE) {
   OmahaResponse response;
 
+  // TODO set better default value for metrics::checkresult in
+  // OmahaRequestAction::ActionCompleted.
   fake_system_state_.fake_hardware()->UnsetIsOOBEComplete();
-  ASSERT_FALSE(
-      TestUpdateCheck(nullptr,  // request_params
-                      fake_update_response_.GetUpdateResponse(),
-                      -1,
-                      false,  // ping_only
-                      ErrorCode::kNonCriticalUpdateInOOBE,
-                      metrics::CheckResult::kUnset,
-                      metrics::CheckReaction::kUnset,
-                      metrics::DownloadErrorCode::kUnset,
-                      &response,
-                      nullptr));
+  ASSERT_FALSE(TestUpdateCheck(nullptr,  // request_params
+                               fake_update_response_.GetUpdateResponse(),
+                               -1,
+                               false,  // ping_only
+                               ErrorCode::kNonCriticalUpdateInOOBE,
+                               metrics::CheckResult::kParsingError,
+                               metrics::CheckReaction::kUnset,
+                               metrics::DownloadErrorCode::kUnset,
+                               &response,
+                               nullptr));
   EXPECT_FALSE(response.update_exists);
 
   // The IsOOBEComplete() value is ignored when the OOBE flow is not enabled.
@@ -1140,6 +1178,37 @@
   EXPECT_EQ(fake_update_response_.cohortname, value);
 }
 
+TEST_F(OmahaRequestActionTest, MultiAppCohortTest) {
+  OmahaResponse response;
+  OmahaRequestParams params = request_params_;
+  fake_update_response_.multi_app = true;
+  fake_update_response_.include_cohorts = true;
+  fake_update_response_.cohort = "s/154454/8479665";
+  fake_update_response_.cohorthint = "please-put-me-on-beta";
+  fake_update_response_.cohortname = "stable";
+
+  ASSERT_TRUE(TestUpdateCheck(&params,
+                              fake_update_response_.GetUpdateResponse(),
+                              -1,
+                              false,  // ping_only
+                              ErrorCode::kSuccess,
+                              metrics::CheckResult::kUpdateAvailable,
+                              metrics::CheckReaction::kUpdating,
+                              metrics::DownloadErrorCode::kUnset,
+                              &response,
+                              nullptr));
+
+  string value;
+  EXPECT_TRUE(fake_prefs_.GetString(kPrefsOmahaCohort, &value));
+  EXPECT_EQ(fake_update_response_.cohort, value);
+
+  EXPECT_TRUE(fake_prefs_.GetString(kPrefsOmahaCohortHint, &value));
+  EXPECT_EQ(fake_update_response_.cohorthint, value);
+
+  EXPECT_TRUE(fake_prefs_.GetString(kPrefsOmahaCohortName, &value));
+  EXPECT_EQ(fake_update_response_.cohortname, value);
+}
+
 TEST_F(OmahaRequestActionTest, NoOutputPipeTest) {
   const string http_response(fake_update_response_.GetNoUpdateResponse());
 
@@ -1148,12 +1217,13 @@
 
   OmahaRequestParams params = request_params_;
   fake_system_state_.set_request_params(&params);
-  OmahaRequestAction action(&fake_system_state_, nullptr,
-                            brillo::make_unique_ptr(
-                                new MockHttpFetcher(http_response.data(),
-                                                    http_response.size(),
-                                                    nullptr)),
-                            false);
+  OmahaRequestAction action(
+      &fake_system_state_,
+      nullptr,
+      std::make_unique<MockHttpFetcher>(http_response.data(),
+                                        http_response.size(),
+                                        nullptr),
+      false);
   OmahaRequestActionTestProcessorDelegate delegate;
   ActionProcessor processor;
   processor.set_delegate(&delegate);
@@ -1263,7 +1333,10 @@
   string input_response =
       "<?xml version=\"1.0\" encoding=\"UTF-8\"?><response protocol=\"3.0\">"
       "<daystart elapsed_seconds=\"100\"/>"
-      "<app appid=\"xyz\" status=\"ok\">"
+      // the appid needs to match that in the request params
+      "<app appid=\"" +
+      fake_update_response_.app_id +
+      "\" status=\"ok\">"
       "<updatecheck status=\"ok\">"
       "<urls><url codebase=\"http://missing/field/test/\"/></urls>"
       "<manifest version=\"10.2.3.4\">"
@@ -1321,12 +1394,13 @@
   loop.SetAsCurrent();
 
   string http_response("doesn't matter");
-  OmahaRequestAction action(&fake_system_state_, nullptr,
-                            brillo::make_unique_ptr(
-                                new MockHttpFetcher(http_response.data(),
-                                                    http_response.size(),
-                                                    nullptr)),
-                            false);
+  OmahaRequestAction action(
+      &fake_system_state_,
+      nullptr,
+      std::make_unique<MockHttpFetcher>(http_response.data(),
+                                        http_response.size(),
+                                        nullptr),
+      false);
   TerminateEarlyTestProcessorDelegate delegate;
   ActionProcessor processor;
   processor.set_delegate(&delegate);
@@ -1461,7 +1535,7 @@
   fake_system_state_.set_prefs(&prefs);
 
   EXPECT_CALL(prefs, GetString(kPrefsPreviousVersion, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(string("")), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(string("")), Return(true)));
   // An existing but empty previous version means that we didn't reboot to a new
   // update, therefore, no need to update the previous version.
   EXPECT_CALL(prefs, SetString(kPrefsPreviousVersion, _)).Times(0);
@@ -1537,10 +1611,9 @@
   OmahaRequestAction update_check_action(
       &fake_system_state_,
       nullptr,
-      brillo::make_unique_ptr(
-          new MockHttpFetcher(http_response.data(),
-                              http_response.size(),
-                              nullptr)),
+      std::make_unique<MockHttpFetcher>(http_response.data(),
+                                        http_response.size(),
+                                        nullptr),
       false);
   EXPECT_FALSE(update_check_action.IsEvent());
 
@@ -1549,10 +1622,9 @@
   OmahaRequestAction event_action(
       &fake_system_state_,
       new OmahaEvent(OmahaEvent::kTypeUpdateComplete),
-      brillo::make_unique_ptr(
-          new MockHttpFetcher(http_response.data(),
-                              http_response.size(),
-                              nullptr)),
+      std::make_unique<MockHttpFetcher>(http_response.data(),
+                                        http_response.size(),
+                                        nullptr),
       false);
   EXPECT_TRUE(event_action.IsEvent());
 }
@@ -1669,23 +1741,22 @@
   int64_t six_days_ago =
       (Time::Now() - TimeDelta::FromHours(6 * 24 + 11)).ToInternalValue();
   EXPECT_CALL(prefs, GetInt64(kPrefsInstallDateDays, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(0), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(0), Return(true)));
   EXPECT_CALL(prefs, GetInt64(kPrefsLastActivePingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(six_days_ago), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(six_days_ago), Return(true)));
   EXPECT_CALL(prefs, GetInt64(kPrefsLastRollCallPingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(five_days_ago), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(five_days_ago), Return(true)));
   brillo::Blob post_data;
-  ASSERT_TRUE(
-      TestUpdateCheck(nullptr,  // request_params
-                      fake_update_response_.GetNoUpdateResponse(),
-                      -1,
-                      ping_only,
-                      ErrorCode::kSuccess,
-                      metrics::CheckResult::kUnset,
-                      metrics::CheckReaction::kUnset,
-                      metrics::DownloadErrorCode::kUnset,
-                      nullptr,
-                      &post_data));
+  ASSERT_TRUE(TestUpdateCheck(nullptr,  // request_params
+                              fake_update_response_.GetNoUpdateResponse(),
+                              -1,
+                              ping_only,
+                              ErrorCode::kSuccess,
+                              metrics::CheckResult::kNoUpdateAvailable,
+                              metrics::CheckReaction::kUnset,
+                              metrics::DownloadErrorCode::kUnset,
+                              nullptr,
+                              &post_data));
   string post_str(post_data.begin(), post_data.end());
   EXPECT_NE(post_str.find("<ping active=\"1\" a=\"6\" r=\"5\"></ping>"),
             string::npos);
@@ -1716,11 +1787,11 @@
       (Time::Now() - TimeDelta::FromHours(3 * 24 + 12)).ToInternalValue();
   int64_t now = Time::Now().ToInternalValue();
   EXPECT_CALL(prefs, GetInt64(kPrefsInstallDateDays, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(0), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(0), Return(true)));
   EXPECT_CALL(prefs, GetInt64(kPrefsLastActivePingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(three_days_ago), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(three_days_ago), Return(true)));
   EXPECT_CALL(prefs, GetInt64(kPrefsLastRollCallPingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(now), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(now), Return(true)));
   brillo::Blob post_data;
   ASSERT_TRUE(
       TestUpdateCheck(nullptr,  // request_params
@@ -1748,11 +1819,11 @@
       (Time::Now() - TimeDelta::FromHours(4 * 24)).ToInternalValue();
   int64_t now = Time::Now().ToInternalValue();
   EXPECT_CALL(prefs, GetInt64(kPrefsInstallDateDays, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(0), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(0), Return(true)));
   EXPECT_CALL(prefs, GetInt64(kPrefsLastActivePingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(now), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(now), Return(true)));
   EXPECT_CALL(prefs, GetInt64(kPrefsLastRollCallPingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(four_days_ago), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(four_days_ago), Return(true)));
   brillo::Blob post_data;
   ASSERT_TRUE(
       TestUpdateCheck(nullptr,  // request_params
@@ -1779,11 +1850,11 @@
   int64_t one_hour_ago =
       (Time::Now() - TimeDelta::FromHours(1)).ToInternalValue();
   EXPECT_CALL(prefs, GetInt64(kPrefsInstallDateDays, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(0), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(0), Return(true)));
   EXPECT_CALL(prefs, GetInt64(kPrefsLastActivePingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(one_hour_ago), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(one_hour_ago), Return(true)));
   EXPECT_CALL(prefs, GetInt64(kPrefsLastRollCallPingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(one_hour_ago), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(one_hour_ago), Return(true)));
   // LastActivePingDay and PrefsLastRollCallPingDay are set even if we didn't
   // send a ping.
   EXPECT_CALL(prefs, SetInt64(kPrefsLastActivePingDay, _))
@@ -1812,9 +1883,9 @@
   fake_system_state_.set_prefs(&prefs);
   int64_t now = Time::Now().ToInternalValue();
   EXPECT_CALL(prefs, GetInt64(kPrefsLastActivePingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(now), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(now), Return(true)));
   EXPECT_CALL(prefs, GetInt64(kPrefsLastRollCallPingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(now), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(now), Return(true)));
   EXPECT_CALL(prefs, SetInt64(kPrefsLastActivePingDay, _)).Times(0);
   EXPECT_CALL(prefs, SetInt64(kPrefsLastRollCallPingDay, _)).Times(0);
   brillo::Blob post_data;
@@ -1841,11 +1912,11 @@
   int64_t future =
       (Time::Now() + TimeDelta::FromHours(3 * 24 + 4)).ToInternalValue();
   EXPECT_CALL(prefs, GetInt64(kPrefsInstallDateDays, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(0), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(0), Return(true)));
   EXPECT_CALL(prefs, GetInt64(kPrefsLastActivePingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(future), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(future), Return(true)));
   EXPECT_CALL(prefs, GetInt64(kPrefsLastRollCallPingDay, _))
-      .WillOnce(DoAll(SetArgumentPointee<1>(future), Return(true)));
+      .WillOnce(DoAll(SetArgPointee<1>(future), Return(true)));
   EXPECT_CALL(prefs, SetInt64(kPrefsLastActivePingDay, _))
       .WillOnce(Return(true));
   EXPECT_CALL(prefs, SetInt64(kPrefsLastRollCallPingDay, _))
@@ -2038,7 +2109,7 @@
   params.set_update_check_count_wait_enabled(false);
 
   Time arbitrary_date;
-  Time::FromString("6/4/1989", &arbitrary_date);
+  ASSERT_TRUE(Time::FromString("6/4/1989", &arbitrary_date));
   fake_system_state_.fake_clock()->SetWallclockTime(arbitrary_date);
   ASSERT_FALSE(TestUpdateCheck(&params,
                                fake_update_response_.GetUpdateResponse(),
@@ -2079,8 +2150,8 @@
   params.set_update_check_count_wait_enabled(false);
 
   Time t1, t2;
-  Time::FromString("1/1/2012", &t1);
-  Time::FromString("1/3/2012", &t2);
+  ASSERT_TRUE(Time::FromString("1/1/2012", &t1));
+  ASSERT_TRUE(Time::FromString("1/3/2012", &t2));
   ASSERT_TRUE(
       fake_prefs_.SetInt64(kPrefsUpdateFirstSeenAt, t1.ToInternalValue()));
   fake_system_state_.fake_clock()->SetWallclockTime(t2);
@@ -2110,7 +2181,7 @@
 
   brillo::Blob post_data;
   OmahaRequestParams params(&fake_system_state_);
-  params.set_root(tempdir.path().value());
+  params.set_root(tempdir.GetPath().value());
   params.set_app_id("{22222222-2222-2222-2222-222222222222}");
   params.set_app_version("1.2.3.4");
   params.set_current_channel("canary-channel");
@@ -2143,7 +2214,7 @@
 
   brillo::Blob post_data;
   OmahaRequestParams params(&fake_system_state_);
-  params.set_root(tempdir.path().value());
+  params.set_root(tempdir.GetPath().value());
   params.set_app_id("{11111111-1111-1111-1111-111111111111}");
   params.set_app_version("5.6.7.8");
   params.set_current_channel("stable-channel");
@@ -2195,6 +2266,35 @@
   EXPECT_EQ(string::npos, post_str.find("<ping"));
 }
 
+// Checks that the initial ping with a=-1 r=-1 is not send when the device
+// first_active_omaha_ping_sent is set.
+TEST_F(OmahaRequestActionTest, PingWhenFirstActiveOmahaPingIsSent) {
+  fake_prefs_.SetString(kPrefsPreviousVersion, "");
+
+  // Flag that the device was not powerwashed in the past.
+  fake_system_state_.fake_hardware()->SetPowerwashCount(0);
+
+  // Flag that the device has sent first active ping in the past.
+  fake_system_state_.fake_hardware()->SetFirstActiveOmahaPingSent();
+
+  brillo::Blob post_data;
+  ASSERT_TRUE(
+      TestUpdateCheck(nullptr,  // request_params
+                      fake_update_response_.GetNoUpdateResponse(),
+                      -1,
+                      false,  // ping_only
+                      ErrorCode::kSuccess,
+                      metrics::CheckResult::kNoUpdateAvailable,
+                      metrics::CheckReaction::kUnset,
+                      metrics::DownloadErrorCode::kUnset,
+                      nullptr,
+                      &post_data));
+  // We shouldn't send a ping in this case since
+  // first_active_omaha_ping_sent=true
+  string post_str(post_data.begin(), post_data.end());
+  EXPECT_EQ(string::npos, post_str.find("<ping"));
+}
+
 // Checks that the event 54 is sent on a reboot to a new update.
 TEST_F(OmahaRequestActionTest, RebootAfterUpdateEvent) {
   // Flag that the device was updated in a previous boot.
diff --git a/omaha_request_params.h b/omaha_request_params.h
index f8e9438..73edd6f 100644
--- a/omaha_request_params.h
+++ b/omaha_request_params.h
@@ -111,6 +111,9 @@
     return image_props_.canary_product_id;
   }
   inline std::string system_app_id() const { return image_props_.system_id; }
+  inline void set_system_app_id(const std::string& system_app_id) {
+    image_props_.system_id = system_app_id;
+  }
   inline void set_app_id(const std::string& app_id) {
     image_props_.product_id = app_id;
     image_props_.canary_product_id = app_id;
@@ -127,6 +130,9 @@
   inline std::string system_version() const {
     return image_props_.system_version;
   }
+  inline std::string product_components() const {
+    return image_props_.product_components;
+  }
 
   inline std::string current_channel() const {
     return image_props_.current_channel;
diff --git a/omaha_request_params_unittest.cc b/omaha_request_params_unittest.cc
index 7d4dc2d..57ecf24 100644
--- a/omaha_request_params_unittest.cc
+++ b/omaha_request_params_unittest.cc
@@ -47,7 +47,7 @@
     // Create a fresh copy of the params for each test, so there's no
     // unintended reuse of state across tests.
     params_ = OmahaRequestParams(&fake_system_state_);
-    params_.set_root(tempdir_.path().value());
+    params_.set_root(tempdir_.GetPath().value());
     SetLockDown(false);
     fake_system_state_.set_prefs(&fake_prefs_);
   }
@@ -105,7 +105,8 @@
 }
 
 TEST_F(OmahaRequestParamsTest, NoDeltasTest) {
-  ASSERT_TRUE(WriteFileString(tempdir_.path().Append(".nodelta").value(), ""));
+  ASSERT_TRUE(
+      WriteFileString(tempdir_.GetPath().Append(".nodelta").value(), ""));
   EXPECT_TRUE(params_.Init("", "", false));
   EXPECT_FALSE(params_.delta_okay());
 }
@@ -113,12 +114,12 @@
 TEST_F(OmahaRequestParamsTest, SetTargetChannelTest) {
   {
     OmahaRequestParams params(&fake_system_state_);
-    params.set_root(tempdir_.path().value());
+    params.set_root(tempdir_.GetPath().value());
     EXPECT_TRUE(params.Init("", "", false));
     EXPECT_TRUE(params.SetTargetChannel("canary-channel", false, nullptr));
     EXPECT_FALSE(params.is_powerwash_allowed());
   }
-  params_.set_root(tempdir_.path().value());
+  params_.set_root(tempdir_.GetPath().value());
   EXPECT_TRUE(params_.Init("", "", false));
   EXPECT_EQ("canary-channel", params_.target_channel());
   EXPECT_FALSE(params_.is_powerwash_allowed());
@@ -127,12 +128,12 @@
 TEST_F(OmahaRequestParamsTest, SetIsPowerwashAllowedTest) {
   {
     OmahaRequestParams params(&fake_system_state_);
-    params.set_root(tempdir_.path().value());
+    params.set_root(tempdir_.GetPath().value());
     EXPECT_TRUE(params.Init("", "", false));
     EXPECT_TRUE(params.SetTargetChannel("canary-channel", true, nullptr));
     EXPECT_TRUE(params.is_powerwash_allowed());
   }
-  params_.set_root(tempdir_.path().value());
+  params_.set_root(tempdir_.GetPath().value());
   EXPECT_TRUE(params_.Init("", "", false));
   EXPECT_EQ("canary-channel", params_.target_channel());
   EXPECT_TRUE(params_.is_powerwash_allowed());
@@ -141,7 +142,7 @@
 TEST_F(OmahaRequestParamsTest, SetTargetChannelInvalidTest) {
   {
     OmahaRequestParams params(&fake_system_state_);
-    params.set_root(tempdir_.path().value());
+    params.set_root(tempdir_.GetPath().value());
     SetLockDown(true);
     EXPECT_TRUE(params.Init("", "", false));
     string error_message;
@@ -151,7 +152,7 @@
     EXPECT_NE(string::npos, error_message.find("stable-channel"));
     EXPECT_FALSE(params.is_powerwash_allowed());
   }
-  params_.set_root(tempdir_.path().value());
+  params_.set_root(tempdir_.GetPath().value());
   EXPECT_TRUE(params_.Init("", "", false));
   EXPECT_EQ("stable-channel", params_.target_channel());
   EXPECT_FALSE(params_.is_powerwash_allowed());
diff --git a/omaha_response.h b/omaha_response.h
index c702068..b973eb5 100644
--- a/omaha_response.h
+++ b/omaha_response.h
@@ -37,6 +37,7 @@
 
   // These are only valid if update_exists is true:
   std::string version;
+  std::string system_version;
 
   struct Package {
     // The ordered list of URLs in the Omaha response. Each item is a complete
diff --git a/omaha_response_handler_action.cc b/omaha_response_handler_action.cc
index 189fe6b..9c5fb4a 100644
--- a/omaha_response_handler_action.cc
+++ b/omaha_response_handler_action.cc
@@ -31,7 +31,11 @@
 #include "update_engine/omaha_request_params.h"
 #include "update_engine/payload_consumer/delta_performer.h"
 #include "update_engine/payload_state_interface.h"
+#include "update_engine/update_manager/policy.h"
+#include "update_engine/update_manager/update_manager.h"
 
+using chromeos_update_manager::Policy;
+using chromeos_update_manager::UpdateManager;
 using std::string;
 
 namespace chromeos_update_engine {
@@ -69,8 +73,10 @@
     return;
   }
 
+  // This is the url to the first package, not all packages.
   install_plan_.download_url = current_url;
   install_plan_.version = response.version;
+  install_plan_.system_version = response.system_version;
 
   OmahaRequestParams* const params = system_state_->request_params();
   PayloadStateInterface* const payload_state = system_state_->payload_state();
@@ -156,7 +162,14 @@
     chmod(deadline_file_.c_str(), S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
   }
 
-  completer.set_code(ErrorCode::kSuccess);
+  // Check the generated install-plan with the Policy to confirm that
+  // it can be applied at this time (or at all).
+  UpdateManager* const update_manager = system_state_->update_manager();
+  CHECK(update_manager);
+  auto ec = ErrorCode::kSuccess;
+  update_manager->PolicyRequest(
+      &Policy::UpdateCanBeApplied, &ec, &install_plan_);
+  completer.set_code(ec);
 }
 
 bool OmahaResponseHandlerAction::AreHashChecksMandatory(
diff --git a/omaha_response_handler_action.h b/omaha_response_handler_action.h
index 51dfa7a..2974841 100644
--- a/omaha_response_handler_action.h
+++ b/omaha_response_handler_action.h
@@ -89,6 +89,7 @@
   friend class OmahaResponseHandlerActionTest;
 
   FRIEND_TEST(UpdateAttempterTest, CreatePendingErrorEventResumedTest);
+  FRIEND_TEST(UpdateAttempterTest, UpdateDeferredByPolicyTest);
 
   DISALLOW_COPY_AND_ASSIGN(OmahaResponseHandlerAction);
 };
diff --git a/omaha_response_handler_action_unittest.cc b/omaha_response_handler_action_unittest.cc
index 75cd819..568d11d 100644
--- a/omaha_response_handler_action_unittest.cc
+++ b/omaha_response_handler_action_unittest.cc
@@ -16,10 +16,12 @@
 
 #include "update_engine/omaha_response_handler_action.h"
 
+#include <memory>
 #include <string>
 
 #include <base/files/file_util.h>
 #include <base/files/scoped_temp_dir.h>
+#include <brillo/message_loops/fake_message_loop.h>
 #include <gtest/gtest.h>
 
 #include "update_engine/common/constants.h"
@@ -29,12 +31,18 @@
 #include "update_engine/fake_system_state.h"
 #include "update_engine/mock_payload_state.h"
 #include "update_engine/payload_consumer/payload_constants.h"
+#include "update_engine/update_manager/mock_policy.h"
 
 using chromeos_update_engine::test_utils::System;
 using chromeos_update_engine::test_utils::WriteFileString;
+using chromeos_update_manager::EvalStatus;
+using chromeos_update_manager::FakeUpdateManager;
+using chromeos_update_manager::MockPolicy;
 using std::string;
-using testing::Return;
 using testing::_;
+using testing::DoAll;
+using testing::Return;
+using testing::SetArgPointee;
 
 namespace chromeos_update_engine {
 
@@ -58,6 +66,13 @@
               const string& deadline_file,
               InstallPlan* out);
 
+  // Pointer to the Action, valid after |DoTest|, released when the test is
+  // finished.
+  std::unique_ptr<OmahaResponseHandlerAction> action_;
+  // Captures the action's result code, for tests that need to directly verify
+  // it in non-success cases.
+  ErrorCode action_result_code_;
+
   FakeSystemState fake_system_state_;
   // "Hash+"
   const brillo::Blob expected_hash_ = {0x48, 0x61, 0x73, 0x68, 0x2b};
@@ -67,8 +82,7 @@
     : public ActionProcessorDelegate {
  public:
   OmahaResponseHandlerActionProcessorDelegate()
-      : code_(ErrorCode::kError),
-        code_set_(false) {}
+      : code_(ErrorCode::kError), code_set_(false) {}
   void ActionCompleted(ActionProcessor* processor,
                        AbstractAction* action,
                        ErrorCode code) {
@@ -95,10 +109,11 @@
 const char* const kPayloadHashHex = "486173682b";
 }  // namespace
 
-bool OmahaResponseHandlerActionTest::DoTest(
-    const OmahaResponse& in,
-    const string& test_deadline_file,
-    InstallPlan* out) {
+bool OmahaResponseHandlerActionTest::DoTest(const OmahaResponse& in,
+                                            const string& test_deadline_file,
+                                            InstallPlan* out) {
+  brillo::FakeMessageLoop loop(nullptr);
+  loop.SetAsCurrent();
   ActionProcessor processor;
   OmahaResponseHandlerActionProcessorDelegate delegate;
   processor.set_delegate(&delegate);
@@ -123,15 +138,15 @@
   EXPECT_CALL(*(fake_system_state_.mock_payload_state()), GetCurrentUrl())
       .WillRepeatedly(Return(current_url));
 
-  OmahaResponseHandlerAction response_handler_action(
+  action_.reset(new OmahaResponseHandlerAction(
       &fake_system_state_,
-      (test_deadline_file.empty() ?
-       constants::kOmahaResponseDeadlineFile : test_deadline_file));
-  BondActions(&feeder_action, &response_handler_action);
+      (test_deadline_file.empty() ? constants::kOmahaResponseDeadlineFile
+                                  : test_deadline_file)));
+  BondActions(&feeder_action, action_.get());
   ObjectCollectorAction<InstallPlan> collector_action;
-  BondActions(&response_handler_action, &collector_action);
+  BondActions(action_.get(), &collector_action);
   processor.EnqueueAction(&feeder_action);
-  processor.EnqueueAction(&response_handler_action);
+  processor.EnqueueAction(action_.get());
   processor.EnqueueAction(&collector_action);
   processor.StartProcessing();
   EXPECT_TRUE(!processor.IsRunning())
@@ -139,14 +154,15 @@
   if (out)
     *out = collector_action.object();
   EXPECT_TRUE(delegate.code_set_);
+  action_result_code_ = delegate.code_;
   return delegate.code_ == ErrorCode::kSuccess;
 }
 
 TEST_F(OmahaResponseHandlerActionTest, SimpleTest) {
   string test_deadline_file;
-  CHECK(utils::MakeTempFile(
-          "omaha_response_handler_action_unittest-XXXXXX",
-          &test_deadline_file, nullptr));
+  CHECK(utils::MakeTempFile("omaha_response_handler_action_unittest-XXXXXX",
+                            &test_deadline_file,
+                            nullptr));
   ScopedPathUnlinker deadline_unlinker(test_deadline_file);
   {
     OmahaResponse in;
@@ -368,7 +384,7 @@
 
   OmahaRequestParams params(&fake_system_state_);
   fake_system_state_.fake_hardware()->SetIsOfficialBuild(false);
-  params.set_root(tempdir.path().value());
+  params.set_root(tempdir.GetPath().value());
   params.set_current_channel("canary-channel");
   // The ImageProperties in Android uses prefs to store MutableImageProperties.
 #ifdef __ANDROID__
@@ -403,7 +419,7 @@
 
   OmahaRequestParams params(&fake_system_state_);
   fake_system_state_.fake_hardware()->SetIsOfficialBuild(false);
-  params.set_root(tempdir.path().value());
+  params.set_root(tempdir.GetPath().value());
   params.set_current_channel("stable-channel");
   // The ImageProperties in Android uses prefs to store MutableImageProperties.
 #ifdef __ANDROID__
@@ -447,7 +463,8 @@
   EXPECT_CALL(*fake_system_state_.mock_payload_state(), GetP2PUrl())
       .WillRepeatedly(Return(p2p_url));
   EXPECT_CALL(*fake_system_state_.mock_payload_state(),
-              GetUsingP2PForDownloading()).WillRepeatedly(Return(true));
+              GetUsingP2PForDownloading())
+      .WillRepeatedly(Return(true));
 
   InstallPlan install_plan;
   EXPECT_TRUE(DoTest(in, "", &install_plan));
@@ -456,4 +473,60 @@
   EXPECT_TRUE(install_plan.hash_checks_mandatory);
 }
 
+TEST_F(OmahaResponseHandlerActionTest, SystemVersionTest) {
+  OmahaResponse in;
+  in.update_exists = true;
+  in.version = "a.b.c.d";
+  in.system_version = "b.c.d.e";
+  in.packages.push_back({.payload_urls = {"http://package/1"},
+                         .size = 1,
+                         .hash = kPayloadHashHex});
+  in.packages.push_back({.payload_urls = {"http://package/2"},
+                         .size = 2,
+                         .hash = kPayloadHashHex});
+  in.more_info_url = "http://more/info";
+  InstallPlan install_plan;
+  EXPECT_TRUE(DoTest(in, "", &install_plan));
+  EXPECT_EQ(in.packages[0].payload_urls[0], install_plan.download_url);
+  EXPECT_EQ(2u, install_plan.payloads.size());
+  EXPECT_EQ(in.packages[0].size, install_plan.payloads[0].size);
+  EXPECT_EQ(in.packages[1].size, install_plan.payloads[1].size);
+  EXPECT_EQ(expected_hash_, install_plan.payloads[0].hash);
+  EXPECT_EQ(expected_hash_, install_plan.payloads[1].hash);
+  EXPECT_EQ(in.version, install_plan.version);
+  EXPECT_EQ(in.system_version, install_plan.system_version);
+}
+
+TEST_F(OmahaResponseHandlerActionTest, TestDeferredByPolicy) {
+  OmahaResponse in;
+  in.update_exists = true;
+  in.version = "a.b.c.d";
+  in.packages.push_back({.payload_urls = {"http://foo/the_update_a.b.c.d.tgz"},
+                         .size = 12,
+                         .hash = kPayloadHashHex});
+  // Setup the UpdateManager to disallow the update.
+  FakeClock fake_clock;
+  MockPolicy* mock_policy = new MockPolicy(&fake_clock);
+  FakeUpdateManager* fake_update_manager =
+      fake_system_state_.fake_update_manager();
+  fake_update_manager->set_policy(mock_policy);
+  EXPECT_CALL(*mock_policy, UpdateCanBeApplied(_, _, _, _, _))
+      .WillOnce(
+          DoAll(SetArgPointee<3>(ErrorCode::kOmahaUpdateDeferredPerPolicy),
+                Return(EvalStatus::kSucceeded)));
+  // Perform the Action. It should "fail" with kOmahaUpdateDeferredPerPolicy.
+  InstallPlan install_plan;
+  EXPECT_FALSE(DoTest(in, "", &install_plan));
+  EXPECT_EQ(ErrorCode::kOmahaUpdateDeferredPerPolicy, action_result_code_);
+  // Verify that DoTest() didn't set the output install plan.
+  EXPECT_EQ("", install_plan.version);
+  // Copy the underlying InstallPlan from the Action (like a real Delegate).
+  install_plan = action_->install_plan();
+  // Now verify the InstallPlan that was generated.
+  EXPECT_EQ(in.packages[0].payload_urls[0], install_plan.download_url);
+  EXPECT_EQ(expected_hash_, install_plan.payloads[0].hash);
+  EXPECT_EQ(1U, install_plan.target_slot);
+  EXPECT_EQ(in.version, install_plan.version);
+}
+
 }  // namespace chromeos_update_engine
diff --git a/parcelable_update_engine_status.cc b/parcelable_update_engine_status.cc
index d8eb6db..8a2dbeb 100644
--- a/parcelable_update_engine_status.cc
+++ b/parcelable_update_engine_status.cc
@@ -15,12 +15,27 @@
 //
 
 #include "update_engine/parcelable_update_engine_status.h"
+#include "update_engine/update_status_utils.h"
 
 #include <binder/Parcel.h>
 
+using update_engine::UpdateEngineStatus;
+
 namespace android {
 namespace brillo {
 
+ParcelableUpdateEngineStatus::ParcelableUpdateEngineStatus(
+    const UpdateEngineStatus& status)
+    : last_checked_time_(status.last_checked_time),
+      current_operation_(
+          chromeos_update_engine::UpdateStatusToString(status.status)),
+      progress_(status.progress),
+      current_version_(String16{status.current_version.c_str()}),
+      current_system_version_(String16{status.current_system_version.c_str()}),
+      new_size_(status.new_size_bytes),
+      new_version_(String16{status.new_version.c_str()}),
+      new_system_version_(String16{status.new_system_version.c_str()}) {}
+
 status_t ParcelableUpdateEngineStatus::writeToParcel(Parcel* parcel) const {
   status_t status;
 
@@ -29,12 +44,27 @@
     return status;
   }
 
+  status = parcel->writeString16(current_operation_);
+  if (status != OK) {
+    return status;
+  }
+
   status = parcel->writeDouble(progress_);
   if (status != OK) {
     return status;
   }
 
-  status = parcel->writeString16(current_operation_);
+  status = parcel->writeString16(current_version_);
+  if (status != OK) {
+    return status;
+  }
+
+  status = parcel->writeString16(current_system_version_);
+  if (status != OK) {
+    return status;
+  }
+
+  status = parcel->writeInt64(new_size_);
   if (status != OK) {
     return status;
   }
@@ -44,7 +74,7 @@
     return status;
   }
 
-  return parcel->writeInt64(new_size_);
+  return parcel->writeString16(new_system_version_);
 }
 
 status_t ParcelableUpdateEngineStatus::readFromParcel(const Parcel* parcel) {
@@ -55,12 +85,27 @@
     return status;
   }
 
+  status = parcel->readString16(&current_operation_);
+  if (status != OK) {
+    return status;
+  }
+
   status = parcel->readDouble(&progress_);
   if (status != OK) {
     return status;
   }
 
-  status = parcel->readString16(&current_operation_);
+  status = parcel->readString16(&current_version_);
+  if (status != OK) {
+    return status;
+  }
+
+  status = parcel->readString16(&current_system_version_);
+  if (status != OK) {
+    return status;
+  }
+
+  status = parcel->readInt64(&new_size_);
   if (status != OK) {
     return status;
   }
@@ -70,7 +115,7 @@
     return status;
   }
 
-  return parcel->readInt64(&new_size_);
+  return parcel->readString16(&new_system_version_);
 }
 
 }  // namespace brillo
diff --git a/parcelable_update_engine_status.h b/parcelable_update_engine_status.h
index 2cfedd9..82006e4 100644
--- a/parcelable_update_engine_status.h
+++ b/parcelable_update_engine_status.h
@@ -20,6 +20,8 @@
 #include <binder/Parcelable.h>
 #include <utils/String16.h>
 
+#include "update_engine/client_library/include/update_engine/update_status.h"
+
 namespace android {
 namespace brillo {
 
@@ -28,16 +30,31 @@
 class ParcelableUpdateEngineStatus : public Parcelable {
  public:
   ParcelableUpdateEngineStatus() = default;
+  explicit ParcelableUpdateEngineStatus(
+      const update_engine::UpdateEngineStatus& status);
   virtual ~ParcelableUpdateEngineStatus() = default;
 
   status_t writeToParcel(Parcel* parcel) const override;
   status_t readFromParcel(const Parcel* parcel) override;
 
+  // This list is kept in the Parcelable serialization order.
+
+  // When the update_engine last checked for updates (seconds since unix Epoch)
   int64_t last_checked_time_;
-  double progress_;
+  // The current status/operation of the update_engine.
   android::String16 current_operation_;
-  android::String16 new_version_;
+  // The current progress (0.0f-1.0f).
+  double progress_;
+  // The current product version.
+  android::String16 current_version_;
+  // The current system version.
+  android::String16 current_system_version_;
+  // The size of the update (bytes).  This is int64_t for java compatibility.
   int64_t new_size_;
+  // The new product version.
+  android::String16 new_version_;
+  // The new system version, if there is one (empty, otherwise).
+  android::String16 new_system_version_;
 };
 
 }  // namespace brillo
diff --git a/parcelable_update_engine_status_unittest.cc b/parcelable_update_engine_status_unittest.cc
new file mode 100644
index 0000000..f4bd518
--- /dev/null
+++ b/parcelable_update_engine_status_unittest.cc
@@ -0,0 +1,92 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/parcelable_update_engine_status.h"
+#include "update_engine/update_status_utils.h"
+
+#include <binder/Parcel.h>
+#include <gtest/gtest.h>
+
+using android::Parcel;
+using android::String16;
+using android::brillo::ParcelableUpdateEngineStatus;
+using android::status_t;
+using update_engine::UpdateEngineStatus;
+using update_engine::UpdateStatus;
+
+TEST(ParcelableUpdateEngineStatusTest, TestCreationFromUpdateEngineStatus) {
+  // This test creates an object and verifies that all the UpdateEngineStatus
+  // values are properly reflected in the Parcelable version of the class.
+
+  UpdateEngineStatus ue_status = {123456789,
+                                  UpdateStatus::DOWNLOADING,
+                                  "0.1.2.3",
+                                  "1.2.3.4",
+                                  0.5f,
+                                  34567,
+                                  "2.3.4.5",
+                                  "3.4.5.6"};
+  ParcelableUpdateEngineStatus parcelable_status(ue_status);
+  EXPECT_EQ(ue_status.last_checked_time, parcelable_status.last_checked_time_);
+  EXPECT_EQ(
+      String16{chromeos_update_engine::UpdateStatusToString(ue_status.status)},
+      parcelable_status.current_operation_);
+  EXPECT_EQ(String16{ue_status.current_version.c_str()},
+            parcelable_status.current_version_);
+  EXPECT_EQ(String16{ue_status.current_system_version.c_str()},
+            parcelable_status.current_system_version_);
+  EXPECT_EQ(ue_status.progress, parcelable_status.progress_);
+  EXPECT_EQ(static_cast<int64_t>(ue_status.new_size_bytes),
+            parcelable_status.new_size_);
+  EXPECT_EQ(String16{ue_status.new_version.c_str()},
+            parcelable_status.new_version_);
+  EXPECT_EQ(String16{ue_status.new_system_version.c_str()},
+            parcelable_status.new_system_version_);
+}
+
+TEST(ParcelableUpdateEngineStatusTest, TestParceling) {
+  // This tests the writeToParcel and readFromParcel methods for being correctly
+  // matched.
+  UpdateEngineStatus ue_status = {123456789,
+                                  UpdateStatus::DOWNLOADING,
+                                  "0.1.2.3",
+                                  "1.2.3.4",
+                                  0.5f,
+                                  34567,
+                                  "2.3.4.5",
+                                  "3.4.5.6"};
+  ParcelableUpdateEngineStatus source_status(ue_status);
+  Parcel parcel_source, parcel_target;
+  status_t status = source_status.writeToParcel(&parcel_source);
+  EXPECT_EQ(::android::OK, status);
+  size_t parcel_len = parcel_source.dataSize();
+  status = parcel_target.setData(parcel_source.data(), parcel_len);
+  EXPECT_EQ(::android::OK, status);
+  ParcelableUpdateEngineStatus target_status;
+  status = target_status.readFromParcel(&parcel_target);
+  EXPECT_EQ(::android::OK, status);
+
+  EXPECT_EQ(source_status.last_checked_time_, target_status.last_checked_time_);
+  EXPECT_EQ(source_status.current_operation_, target_status.current_operation_);
+  EXPECT_EQ(source_status.current_version_, target_status.current_version_);
+  EXPECT_EQ(source_status.current_system_version_,
+            target_status.current_system_version_);
+  EXPECT_EQ(source_status.progress_, target_status.progress_);
+  EXPECT_EQ(source_status.new_size_, target_status.new_size_);
+  EXPECT_EQ(source_status.new_version_, target_status.new_version_);
+  EXPECT_EQ(source_status.new_system_version_,
+            target_status.new_system_version_);
+}
diff --git a/payload_consumer/bzip_extent_writer.cc b/payload_consumer/bzip_extent_writer.cc
index 0fcc8ba..39d9d67 100644
--- a/payload_consumer/bzip_extent_writer.cc
+++ b/payload_consumer/bzip_extent_writer.cc
@@ -16,7 +16,7 @@
 
 #include "update_engine/payload_consumer/bzip_extent_writer.h"
 
-using std::vector;
+using google::protobuf::RepeatedPtrField;
 
 namespace chromeos_update_engine {
 
@@ -25,7 +25,7 @@
 }
 
 bool BzipExtentWriter::Init(FileDescriptorPtr fd,
-                            const vector<Extent>& extents,
+                            const RepeatedPtrField<Extent>& extents,
                             uint32_t block_size) {
   // Init bzip2 stream
   int rc = BZ2_bzDecompressInit(&stream_,
diff --git a/payload_consumer/bzip_extent_writer.h b/payload_consumer/bzip_extent_writer.h
index 0ad542e..86b346a 100644
--- a/payload_consumer/bzip_extent_writer.h
+++ b/payload_consumer/bzip_extent_writer.h
@@ -19,7 +19,7 @@
 
 #include <bzlib.h>
 #include <memory>
-#include <vector>
+#include <utility>
 
 #include <brillo/secure_blob.h>
 
@@ -41,7 +41,7 @@
   ~BzipExtentWriter() override = default;
 
   bool Init(FileDescriptorPtr fd,
-            const std::vector<Extent>& extents,
+            const google::protobuf::RepeatedPtrField<Extent>& extents,
             uint32_t block_size) override;
   bool Write(const void* bytes, size_t count) override;
   bool EndImpl() override;
diff --git a/payload_consumer/bzip_extent_writer_unittest.cc b/payload_consumer/bzip_extent_writer_unittest.cc
index 8ac3e59..bf050ef 100644
--- a/payload_consumer/bzip_extent_writer_unittest.cc
+++ b/payload_consumer/bzip_extent_writer_unittest.cc
@@ -19,15 +19,17 @@
 #include <fcntl.h>
 
 #include <algorithm>
+#include <memory>
 #include <string>
 #include <vector>
 
-#include <brillo/make_unique_ptr.h>
 #include <gtest/gtest.h>
 
 #include "update_engine/common/test_utils.h"
 #include "update_engine/common/utils.h"
+#include "update_engine/payload_generator/extent_ranges.h"
 
+using google::protobuf::RepeatedPtrField;
 using std::min;
 using std::string;
 using std::vector;
@@ -55,11 +57,7 @@
 };
 
 TEST_F(BzipExtentWriterTest, SimpleTest) {
-  vector<Extent> extents;
-  Extent extent;
-  extent.set_start_block(0);
-  extent.set_num_blocks(1);
-  extents.push_back(extent);
+  vector<Extent> extents = {ExtentForRange(0, 1)};
 
   // 'echo test | bzip2 | hexdump' yields:
   static const char test_uncompressed[] = "test\n";
@@ -70,9 +68,9 @@
     0x22, 0x9c, 0x28, 0x48, 0x66, 0x61, 0xb8, 0xea, 0x00,
   };
 
-  BzipExtentWriter bzip_writer(
-      brillo::make_unique_ptr(new DirectExtentWriter()));
-  EXPECT_TRUE(bzip_writer.Init(fd_, extents, kBlockSize));
+  BzipExtentWriter bzip_writer(std::make_unique<DirectExtentWriter>());
+  EXPECT_TRUE(
+      bzip_writer.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
   EXPECT_TRUE(bzip_writer.Write(test, sizeof(test)));
   EXPECT_TRUE(bzip_writer.End());
 
@@ -102,15 +100,12 @@
   for (size_t i = 0; i < decompressed_data.size(); ++i)
     decompressed_data[i] = static_cast<uint8_t>("ABC\n"[i % 4]);
 
-  vector<Extent> extents;
-  Extent extent;
-  extent.set_start_block(0);
-  extent.set_num_blocks((kDecompressedLength + kBlockSize - 1) / kBlockSize);
-  extents.push_back(extent);
+  vector<Extent> extents = {
+      ExtentForRange(0, (kDecompressedLength + kBlockSize - 1) / kBlockSize)};
 
-  BzipExtentWriter bzip_writer(
-      brillo::make_unique_ptr(new DirectExtentWriter()));
-  EXPECT_TRUE(bzip_writer.Init(fd_, extents, kBlockSize));
+  BzipExtentWriter bzip_writer(std::make_unique<DirectExtentWriter>());
+  EXPECT_TRUE(
+      bzip_writer.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
 
   brillo::Blob original_compressed_data = compressed_data;
   for (brillo::Blob::size_type i = 0; i < compressed_data.size();
diff --git a/payload_consumer/cached_file_descriptor.cc b/payload_consumer/cached_file_descriptor.cc
new file mode 100644
index 0000000..7f2515e
--- /dev/null
+++ b/payload_consumer/cached_file_descriptor.cc
@@ -0,0 +1,98 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/payload_consumer/cached_file_descriptor.h"
+
+#include <unistd.h>
+
+#include <algorithm>
+
+#include <base/logging.h>
+
+#include "update_engine/common/utils.h"
+
+namespace chromeos_update_engine {
+
+off64_t CachedFileDescriptor::Seek(off64_t offset, int whence) {
+  // Only support SEEK_SET and SEEK_CUR. I think these two would be enough. If
+  // we want to support SEEK_END then we have to figure out the size of the
+  // underlying file descriptor each time and it may not be a very good idea.
+  CHECK(whence == SEEK_SET || whence == SEEK_CUR);
+  off64_t next_offset = whence == SEEK_SET ? offset : offset_ + offset;
+
+  if (next_offset != offset_) {
+    // We sought somewhere other than what we are now. So we have to flush and
+    // move to the new offset.
+    if (!FlushCache()) {
+      return -1;
+    }
+    // Then we have to seek there.
+    if (fd_->Seek(next_offset, SEEK_SET) < 0) {
+      return -1;
+    }
+    offset_ = next_offset;
+  }
+  return offset_;
+}
+
+ssize_t CachedFileDescriptor::Write(const void* buf, size_t count) {
+  auto bytes = static_cast<const uint8_t*>(buf);
+  size_t total_bytes_wrote = 0;
+  while (total_bytes_wrote < count) {
+    auto bytes_to_cache =
+        std::min(count - total_bytes_wrote, cache_.size() - bytes_cached_);
+    if (bytes_to_cache > 0) {  // Which means |cache_| is still have some space.
+      memcpy(cache_.data() + bytes_cached_,
+             bytes + total_bytes_wrote,
+             bytes_to_cache);
+      total_bytes_wrote += bytes_to_cache;
+      bytes_cached_ += bytes_to_cache;
+    }
+    if (bytes_cached_ == cache_.size()) {
+      // Cache is full; write it to the |fd_| as long as you can.
+      if (!FlushCache()) {
+        return -1;
+      }
+    }
+  }
+  offset_ += total_bytes_wrote;
+  return total_bytes_wrote;
+}
+
+bool CachedFileDescriptor::Flush() {
+  return FlushCache() && fd_->Flush();
+}
+
+bool CachedFileDescriptor::Close() {
+  offset_ = 0;
+  return FlushCache() && fd_->Close();
+}
+
+bool CachedFileDescriptor::FlushCache() {
+  size_t begin = 0;
+  while (begin < bytes_cached_) {
+    auto bytes_wrote = fd_->Write(cache_.data() + begin, bytes_cached_ - begin);
+    if (bytes_wrote < 0) {
+      PLOG(ERROR) << "Failed to flush cached data!";
+      return false;
+    }
+    begin += bytes_wrote;
+  }
+  bytes_cached_ = 0;
+  return true;
+}
+
+}  // namespace chromeos_update_engine
diff --git a/payload_consumer/cached_file_descriptor.h b/payload_consumer/cached_file_descriptor.h
new file mode 100644
index 0000000..28c48f7
--- /dev/null
+++ b/payload_consumer/cached_file_descriptor.h
@@ -0,0 +1,76 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_PAYLOAD_CONSUMER_CACHED_FILE_DESCRIPTOR_H_
+#define UPDATE_ENGINE_PAYLOAD_CONSUMER_CACHED_FILE_DESCRIPTOR_H_
+
+#include <errno.h>
+#include <sys/types.h>
+
+#include <memory>
+#include <vector>
+
+#include <brillo/secure_blob.h>
+
+#include "update_engine/payload_consumer/file_descriptor.h"
+
+namespace chromeos_update_engine {
+
+class CachedFileDescriptor : public FileDescriptor {
+ public:
+  CachedFileDescriptor(FileDescriptorPtr fd, size_t cache_size) : fd_(fd) {
+    cache_.resize(cache_size);
+  }
+  ~CachedFileDescriptor() override = default;
+
+  bool Open(const char* path, int flags, mode_t mode) override {
+    return fd_->Open(path, flags, mode);
+  }
+  bool Open(const char* path, int flags) override {
+    return fd_->Open(path, flags);
+  }
+  ssize_t Read(void* buf, size_t count) override {
+    return fd_->Read(buf, count);
+  }
+  ssize_t Write(const void* buf, size_t count) override;
+  off64_t Seek(off64_t offset, int whence) override;
+  uint64_t BlockDevSize() override { return fd_->BlockDevSize(); }
+  bool BlkIoctl(int request,
+                uint64_t start,
+                uint64_t length,
+                int* result) override {
+    return fd_->BlkIoctl(request, start, length, result);
+  }
+  bool Flush() override;
+  bool Close() override;
+  bool IsSettingErrno() override { return fd_->IsSettingErrno(); }
+  bool IsOpen() override { return fd_->IsOpen(); }
+
+ private:
+  // Internal flush without the need to call |fd_->Flush()|.
+  bool FlushCache();
+
+  FileDescriptorPtr fd_;
+  brillo::Blob cache_;
+  size_t bytes_cached_{0};
+  off64_t offset_{0};
+
+  DISALLOW_COPY_AND_ASSIGN(CachedFileDescriptor);
+};
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_PAYLOAD_CONSUMER_CACHED_FILE_DESCRIPTOR_H_
diff --git a/payload_consumer/cached_file_descriptor_unittest.cc b/payload_consumer/cached_file_descriptor_unittest.cc
new file mode 100644
index 0000000..6a6302a
--- /dev/null
+++ b/payload_consumer/cached_file_descriptor_unittest.cc
@@ -0,0 +1,204 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/payload_consumer/cached_file_descriptor.h"
+
+#include <fcntl.h>
+
+#include <algorithm>
+#include <string>
+#include <vector>
+
+#include <gtest/gtest.h>
+
+#include "update_engine/common/test_utils.h"
+#include "update_engine/common/utils.h"
+
+using chromeos_update_engine::test_utils::ExpectVectorsEq;
+using std::min;
+using std::string;
+using std::vector;
+
+namespace chromeos_update_engine {
+
+namespace {
+const size_t kCacheSize = 100;
+const size_t kFileSize = 1024;
+const size_t kRandomIterations = 1000;
+}  // namespace
+
+class CachedFileDescriptorTest : public ::testing::Test {
+ public:
+  void Open() {
+    cfd_.reset(new CachedFileDescriptor(fd_, kCacheSize));
+    EXPECT_TRUE(cfd_->Open(temp_file_.path().c_str(), O_RDWR, 0600));
+  }
+
+  void Write(uint8_t* buffer, size_t count) {
+    size_t total_bytes_wrote = 0;
+    while (total_bytes_wrote < count) {
+      auto bytes_wrote =
+          cfd_->Write(buffer + total_bytes_wrote, count - total_bytes_wrote);
+      ASSERT_NE(bytes_wrote, -1);
+      total_bytes_wrote += bytes_wrote;
+    }
+  }
+
+  void Close() { EXPECT_TRUE(cfd_->Close()); }
+
+  void SetUp() override {
+    brillo::Blob zero_blob(kFileSize, 0);
+    EXPECT_TRUE(utils::WriteFile(
+        temp_file_.path().c_str(), zero_blob.data(), zero_blob.size()));
+    Open();
+  }
+
+  void TearDown() override {
+    Close();
+    EXPECT_FALSE(cfd_->IsOpen());
+  }
+
+ protected:
+  FileDescriptorPtr fd_{new EintrSafeFileDescriptor};
+  test_utils::ScopedTempFile temp_file_{"CachedFileDescriptor-file.XXXXXX"};
+  int value_{1};
+  FileDescriptorPtr cfd_;
+};
+
+TEST_F(CachedFileDescriptorTest, IsOpenTest) {
+  EXPECT_TRUE(cfd_->IsOpen());
+}
+
+TEST_F(CachedFileDescriptorTest, SimpleWriteTest) {
+  EXPECT_EQ(cfd_->Seek(0, SEEK_SET), 0);
+  brillo::Blob blob_in(kFileSize, value_);
+  Write(blob_in.data(), blob_in.size());
+  EXPECT_TRUE(cfd_->Flush());
+
+  brillo::Blob blob_out;
+  EXPECT_TRUE(utils::ReadFile(temp_file_.path(), &blob_out));
+  EXPECT_EQ(blob_in, blob_out);
+}
+
+TEST_F(CachedFileDescriptorTest, OneBytePerWriteTest) {
+  EXPECT_EQ(cfd_->Seek(0, SEEK_SET), 0);
+  brillo::Blob blob_in(kFileSize, value_);
+  for (size_t idx = 0; idx < blob_in.size(); idx++) {
+    Write(&blob_in[idx], 1);
+  }
+  EXPECT_TRUE(cfd_->Flush());
+
+  brillo::Blob blob_out;
+  EXPECT_TRUE(utils::ReadFile(temp_file_.path(), &blob_out));
+  EXPECT_EQ(blob_in, blob_out);
+}
+
+TEST_F(CachedFileDescriptorTest, RandomWriteTest) {
+  EXPECT_EQ(cfd_->Seek(0, SEEK_SET), 0);
+
+  brillo::Blob blob_in(kFileSize, 0);
+  srand(time(nullptr));
+  uint32_t rand_seed;
+  for (size_t idx = 0; idx < kRandomIterations; idx++) {
+    // zero to full size available.
+    size_t start = rand_r(&rand_seed) % blob_in.size();
+    size_t size = rand_r(&rand_seed) % (blob_in.size() - start);
+    std::fill_n(&blob_in[start], size, idx % 256);
+    EXPECT_EQ(cfd_->Seek(start, SEEK_SET), static_cast<off64_t>(start));
+    Write(&blob_in[start], size);
+  }
+  EXPECT_TRUE(cfd_->Flush());
+
+  brillo::Blob blob_out;
+  EXPECT_TRUE(utils::ReadFile(temp_file_.path(), &blob_out));
+  EXPECT_EQ(blob_in, blob_out);
+}
+
+TEST_F(CachedFileDescriptorTest, SeekTest) {
+  EXPECT_EQ(cfd_->Seek(0, SEEK_SET), 0);
+  EXPECT_EQ(cfd_->Seek(1, SEEK_SET), 1);
+  EXPECT_EQ(cfd_->Seek(kFileSize - 1, SEEK_SET),
+            static_cast<off64_t>(kFileSize - 1));
+  EXPECT_EQ(cfd_->Seek(kFileSize, SEEK_SET), static_cast<off64_t>(kFileSize));
+  EXPECT_EQ(cfd_->Seek(kFileSize + 1, SEEK_SET),
+            static_cast<off64_t>(kFileSize + 1));
+
+  EXPECT_EQ(cfd_->Seek(0, SEEK_SET), 0);
+  EXPECT_EQ(cfd_->Seek(1, SEEK_CUR), 1);
+  EXPECT_EQ(cfd_->Seek(1, SEEK_CUR), 2);
+  EXPECT_EQ(cfd_->Seek(kFileSize - 1, SEEK_SET),
+            static_cast<off64_t>(kFileSize - 1));
+  EXPECT_EQ(cfd_->Seek(1, SEEK_CUR), static_cast<off64_t>(kFileSize));
+  EXPECT_EQ(cfd_->Seek(1, SEEK_CUR), static_cast<off64_t>(kFileSize + 1));
+}
+
+TEST_F(CachedFileDescriptorTest, NoFlushTest) {
+  EXPECT_EQ(cfd_->Seek(0, SEEK_SET), 0);
+  brillo::Blob blob_in(kFileSize, value_);
+  Write(blob_in.data(), blob_in.size());
+
+  brillo::Blob blob_out;
+  EXPECT_TRUE(utils::ReadFile(temp_file_.path(), &blob_out));
+  EXPECT_NE(blob_in, blob_out);
+}
+
+TEST_F(CachedFileDescriptorTest, CacheSizeWriteTest) {
+  off64_t seek = 10;
+  brillo::Blob blob_in(kFileSize, 0);
+  std::fill_n(&blob_in[seek], kCacheSize, value_);
+  // We are writing exactly one cache size; Then it should be commited.
+  EXPECT_EQ(cfd_->Seek(seek, SEEK_SET), seek);
+  Write(&blob_in[seek], kCacheSize);
+
+  brillo::Blob blob_out;
+  EXPECT_TRUE(utils::ReadFile(temp_file_.path(), &blob_out));
+  EXPECT_EQ(blob_in, blob_out);
+}
+
+TEST_F(CachedFileDescriptorTest, UnderCacheSizeWriteTest) {
+  off64_t seek = 100;
+  size_t less_than_cache_size = kCacheSize - 1;
+  EXPECT_EQ(cfd_->Seek(seek, SEEK_SET), seek);
+  brillo::Blob blob_in(kFileSize, 0);
+  std::fill_n(&blob_in[seek], less_than_cache_size, value_);
+  // We are writing less than one cache size; then it should not be commited.
+  Write(&blob_in[seek], less_than_cache_size);
+
+  // Revert the changes in |blob_in|.
+  std::fill_n(&blob_in[seek], less_than_cache_size, 0);
+  brillo::Blob blob_out;
+  EXPECT_TRUE(utils::ReadFile(temp_file_.path(), &blob_out));
+  EXPECT_EQ(blob_in, blob_out);
+}
+
+TEST_F(CachedFileDescriptorTest, SeekAfterWriteTest) {
+  off64_t seek = 100;
+  size_t less_than_cache_size = kCacheSize - 3;
+  EXPECT_EQ(cfd_->Seek(seek, SEEK_SET), seek);
+  brillo::Blob blob_in(kFileSize, 0);
+  std::fill_n(&blob_in[seek], less_than_cache_size, value_);
+  // We are writing less than  one cache size; then it should not be commited.
+  Write(&blob_in[seek], less_than_cache_size);
+
+  // Then we seek, it should've written the cache after seek.
+  EXPECT_EQ(cfd_->Seek(200, SEEK_SET), 200);
+
+  brillo::Blob blob_out;
+  EXPECT_TRUE(utils::ReadFile(temp_file_.path(), &blob_out));
+  EXPECT_EQ(blob_in, blob_out);
+}
+
+}  // namespace chromeos_update_engine
diff --git a/payload_consumer/delta_performer.cc b/payload_consumer/delta_performer.cc
index e158b33..001c84a 100644
--- a/payload_consumer/delta_performer.cc
+++ b/payload_consumer/delta_performer.cc
@@ -24,17 +24,20 @@
 #include <cstring>
 #include <memory>
 #include <string>
+#include <utility>
 #include <vector>
 
 #include <base/files/file_util.h>
 #include <base/format_macros.h>
+#include <base/metrics/histogram_macros.h>
 #include <base/strings/string_number_conversions.h>
 #include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
+#include <base/time/time.h>
 #include <brillo/data_encoding.h>
-#include <brillo/make_unique_ptr.h>
 #include <bsdiff/bspatch.h>
 #include <google/protobuf/repeated_field.h>
+#include <puffin/puffpatch.h>
 
 #include "update_engine/common/constants.h"
 #include "update_engine/common/hardware_interface.h"
@@ -42,8 +45,11 @@
 #include "update_engine/common/subprocess.h"
 #include "update_engine/common/terminator.h"
 #include "update_engine/payload_consumer/bzip_extent_writer.h"
+#include "update_engine/payload_consumer/cached_file_descriptor.h"
 #include "update_engine/payload_consumer/download_action.h"
+#include "update_engine/payload_consumer/extent_reader.h"
 #include "update_engine/payload_consumer/extent_writer.h"
+#include "update_engine/payload_consumer/file_descriptor_utils.h"
 #if USE_MTD
 #include "update_engine/payload_consumer/mtd_file_descriptor.h"
 #endif
@@ -66,7 +72,7 @@
 const uint64_t DeltaPerformer::kDeltaMetadataSignatureSizeSize = 4;
 const uint64_t DeltaPerformer::kMaxPayloadHeaderSize = 24;
 const uint64_t DeltaPerformer::kSupportedMajorPayloadVersion = 2;
-const uint32_t DeltaPerformer::kSupportedMinorPayloadVersion = 3;
+const uint32_t DeltaPerformer::kSupportedMinorPayloadVersion = 4;
 
 const unsigned DeltaPerformer::kProgressLogMaxChunks = 10;
 const unsigned DeltaPerformer::kProgressLogTimeoutSeconds = 30;
@@ -80,6 +86,8 @@
 const int kUbiVolumeAttachTimeout = 5 * 60;
 #endif
 
+const uint64_t kCacheSize = 1024 * 1024;  // 1MB
+
 FileDescriptorPtr CreateFileDescriptor(const char* path) {
   FileDescriptorPtr ret;
 #if USE_MTD
@@ -110,12 +118,20 @@
 
 // Opens path for read/write. On success returns an open FileDescriptor
 // and sets *err to 0. On failure, sets *err to errno and returns nullptr.
-FileDescriptorPtr OpenFile(const char* path, int mode, int* err) {
+FileDescriptorPtr OpenFile(const char* path,
+                           int mode,
+                           bool cache_writes,
+                           int* err) {
   // Try to mark the block device read-only based on the mode. Ignore any
   // failure since this won't work when passing regular files.
-  utils::SetBlockDeviceReadOnly(path, (mode & O_ACCMODE) == O_RDONLY);
+  bool read_only = (mode & O_ACCMODE) == O_RDONLY;
+  utils::SetBlockDeviceReadOnly(path, read_only);
 
   FileDescriptorPtr fd = CreateFileDescriptor(path);
+  if (cache_writes && !read_only) {
+    fd = FileDescriptorPtr(new CachedFileDescriptor(fd, kCacheSize));
+    LOG(INFO) << "Caching writes.";
+  }
 #if USE_MTD
   // On NAND devices, we can either read, or write, but not both. So here we
   // use O_WRONLY.
@@ -271,6 +287,7 @@
   size_t read_len = min(count, max - buffer_.size());
   const char* bytes_start = *bytes_p;
   const char* bytes_end = bytes_start + read_len;
+  buffer_.reserve(max);
   buffer_.insert(buffer_.end(), bytes_start, bytes_end);
   *bytes_p = bytes_end;
   *count_p = count - read_len;
@@ -344,7 +361,7 @@
       GetMinorVersion() != kInPlaceMinorPayloadVersion) {
     source_path_ = install_part.source_path;
     int err;
-    source_fd_ = OpenFile(source_path_.c_str(), O_RDONLY, &err);
+    source_fd_ = OpenFile(source_path_.c_str(), O_RDONLY, false, &err);
     if (!source_fd_) {
       LOG(ERROR) << "Unable to open source partition "
                  << partition.partition_name() << " on slot "
@@ -356,7 +373,15 @@
 
   target_path_ = install_part.target_path;
   int err;
-  target_fd_ = OpenFile(target_path_.c_str(), O_RDWR, &err);
+
+  int flags = O_RDWR;
+  if (!is_interactive_)
+    flags |= O_DSYNC;
+
+  LOG(INFO) << "Opening " << target_path_ << " partition with"
+            << (is_interactive_ ? "out" : "") << " O_DSYNC";
+
+  target_fd_ = OpenFile(target_path_.c_str(), flags, true, &err);
   if (!target_fd_) {
     LOG(ERROR) << "Unable to open target partition "
                << partition.partition_name() << " on slot "
@@ -582,12 +607,20 @@
   return kMetadataParseSuccess;
 }
 
+#define OP_DURATION_HISTOGRAM(_op_name, _start_time)      \
+    LOCAL_HISTOGRAM_CUSTOM_TIMES(                         \
+        "UpdateEngine.DownloadAction.InstallOperation::"  \
+        _op_name ".Duration",                             \
+        base::TimeTicks::Now() - _start_time,             \
+        base::TimeDelta::FromMilliseconds(10),            \
+        base::TimeDelta::FromMinutes(5),                  \
+        20);
+
 // Wrapper around write. Returns true if all requested bytes
 // were written, or false on any error, regardless of progress
 // and stores an action exit code in |error|.
 bool DeltaPerformer::Write(const void* bytes, size_t count, ErrorCode *error) {
   *error = ErrorCode::kSuccess;
-
   const char* c_bytes = reinterpret_cast<const char*>(bytes);
 
   // Update the total byte downloaded count and the progress logs.
@@ -717,32 +750,41 @@
     ScopedTerminatorExitUnblocker exit_unblocker =
         ScopedTerminatorExitUnblocker();  // Avoids a compiler unused var bug.
 
+    base::TimeTicks op_start_time = base::TimeTicks::Now();
+
     bool op_result;
     switch (op.type()) {
       case InstallOperation::REPLACE:
       case InstallOperation::REPLACE_BZ:
       case InstallOperation::REPLACE_XZ:
         op_result = PerformReplaceOperation(op);
+        OP_DURATION_HISTOGRAM("REPLACE", op_start_time);
         break;
       case InstallOperation::ZERO:
       case InstallOperation::DISCARD:
         op_result = PerformZeroOrDiscardOperation(op);
+        OP_DURATION_HISTOGRAM("ZERO_OR_DISCARD", op_start_time);
         break;
       case InstallOperation::MOVE:
         op_result = PerformMoveOperation(op);
+        OP_DURATION_HISTOGRAM("MOVE", op_start_time);
         break;
       case InstallOperation::BSDIFF:
         op_result = PerformBsdiffOperation(op);
+        OP_DURATION_HISTOGRAM("BSDIFF", op_start_time);
         break;
       case InstallOperation::SOURCE_COPY:
         op_result = PerformSourceCopyOperation(op, error);
+        OP_DURATION_HISTOGRAM("SOURCE_COPY", op_start_time);
         break;
       case InstallOperation::SOURCE_BSDIFF:
+      case InstallOperation::BROTLI_BSDIFF:
         op_result = PerformSourceBsdiffOperation(op, error);
+        OP_DURATION_HISTOGRAM("SOURCE_BSDIFF", op_start_time);
         break;
-      case InstallOperation::IMGDIFF:
-        // TODO(deymo): Replace with PUFFIN operation.
-        op_result = false;
+      case InstallOperation::PUFFDIFF:
+        op_result = PerformPuffDiffOperation(op, error);
+        OP_DURATION_HISTOGRAM("PUFFDIFF", op_start_time);
         break;
       default:
         op_result = false;
@@ -750,6 +792,10 @@
     if (!HandleOpResult(op_result, InstallOperationTypeName(op.type()), error))
       return false;
 
+    if (!target_fd_->Flush()) {
+      return false;
+    }
+
     next_operation_num_++;
     UpdateOverallProgress(false, "Completed ");
     CheckpointUpdateProgress();
@@ -917,9 +963,8 @@
   }
 
   // Setup the ExtentWriter stack based on the operation type.
-  std::unique_ptr<ExtentWriter> writer =
-    brillo::make_unique_ptr(new ZeroPadExtentWriter(
-      brillo::make_unique_ptr(new DirectExtentWriter())));
+  std::unique_ptr<ExtentWriter> writer = std::make_unique<ZeroPadExtentWriter>(
+      std::make_unique<DirectExtentWriter>());
 
   if (operation.type() == InstallOperation::REPLACE_BZ) {
     writer.reset(new BzipExtentWriter(std::move(writer)));
@@ -927,13 +972,8 @@
     writer.reset(new XzExtentWriter(std::move(writer)));
   }
 
-  // Create a vector of extents to pass to the ExtentWriter.
-  vector<Extent> extents;
-  for (int i = 0; i < operation.dst_extents_size(); i++) {
-    extents.push_back(operation.dst_extents(i));
-  }
-
-  TEST_AND_RETURN_FALSE(writer->Init(target_fd_, extents, block_size_));
+  TEST_AND_RETURN_FALSE(
+      writer->Init(target_fd_, operation.dst_extents(), block_size_));
   TEST_AND_RETURN_FALSE(writer->Write(buffer_.data(), operation.data_length()));
   TEST_AND_RETURN_FALSE(writer->End());
 
@@ -975,8 +1015,8 @@
     for (uint64_t offset = 0; offset < length; offset += zeros.size()) {
       uint64_t chunk_length = min(length - offset,
                                   static_cast<uint64_t>(zeros.size()));
-      TEST_AND_RETURN_FALSE(
-          utils::PWriteAll(target_fd_, zeros.data(), chunk_length, start + offset));
+      TEST_AND_RETURN_FALSE(utils::PWriteAll(
+          target_fd_, zeros.data(), chunk_length, start + offset));
     }
   }
   return true;
@@ -1035,25 +1075,6 @@
 
 namespace {
 
-// Takes |extents| and fills an empty vector |blocks| with a block index for
-// each block in |extents|. For example, [(3, 2), (8, 1)] would give [3, 4, 8].
-void ExtentsToBlocks(const RepeatedPtrField<Extent>& extents,
-                     vector<uint64_t>* blocks) {
-  for (const Extent& ext : extents) {
-    for (uint64_t j = 0; j < ext.num_blocks(); j++)
-      blocks->push_back(ext.start_block() + j);
-  }
-}
-
-// Takes |extents| and returns the number of blocks in those extents.
-uint64_t GetBlockCount(const RepeatedPtrField<Extent>& extents) {
-  uint64_t sum = 0;
-  for (const Extent& ext : extents) {
-    sum += ext.num_blocks();
-  }
-  return sum;
-}
-
 // Compare |calculated_hash| with source hash in |operation|, return false and
 // dump hash and set |error| if don't match.
 bool ValidateSourceHash(const brillo::Blob& calculated_hash,
@@ -1099,57 +1120,18 @@
   if (operation.has_dst_length())
     TEST_AND_RETURN_FALSE(operation.dst_length() % block_size_ == 0);
 
-  uint64_t blocks_to_read = GetBlockCount(operation.src_extents());
-  uint64_t blocks_to_write = GetBlockCount(operation.dst_extents());
-  TEST_AND_RETURN_FALSE(blocks_to_write ==  blocks_to_read);
-
-  // Create vectors of all the individual src/dst blocks.
-  vector<uint64_t> src_blocks;
-  vector<uint64_t> dst_blocks;
-  ExtentsToBlocks(operation.src_extents(), &src_blocks);
-  ExtentsToBlocks(operation.dst_extents(), &dst_blocks);
-  DCHECK_EQ(src_blocks.size(), blocks_to_read);
-  DCHECK_EQ(src_blocks.size(), dst_blocks.size());
-
-  brillo::Blob buf(block_size_);
-  ssize_t bytes_read = 0;
-  HashCalculator source_hasher;
-  // Read/write one block at a time.
-  for (uint64_t i = 0; i < blocks_to_read; i++) {
-    ssize_t bytes_read_this_iteration = 0;
-    uint64_t src_block = src_blocks[i];
-    uint64_t dst_block = dst_blocks[i];
-
-    // Read in bytes.
-    TEST_AND_RETURN_FALSE(
-        utils::PReadAll(source_fd_,
-                        buf.data(),
-                        block_size_,
-                        src_block * block_size_,
-                        &bytes_read_this_iteration));
-
-    // Write bytes out.
-    TEST_AND_RETURN_FALSE(
-        utils::PWriteAll(target_fd_,
-                         buf.data(),
-                         block_size_,
-                         dst_block * block_size_));
-
-    bytes_read += bytes_read_this_iteration;
-    TEST_AND_RETURN_FALSE(bytes_read_this_iteration ==
-                          static_cast<ssize_t>(block_size_));
-
-    if (operation.has_src_sha256_hash())
-      TEST_AND_RETURN_FALSE(source_hasher.Update(buf.data(), buf.size()));
-  }
+  brillo::Blob source_hash;
+  TEST_AND_RETURN_FALSE(fd_utils::CopyAndHashExtents(source_fd_,
+                                                     operation.src_extents(),
+                                                     target_fd_,
+                                                     operation.dst_extents(),
+                                                     block_size_,
+                                                     &source_hash));
 
   if (operation.has_src_sha256_hash()) {
-    TEST_AND_RETURN_FALSE(source_hasher.Finalize());
-    TEST_AND_RETURN_FALSE(
-        ValidateSourceHash(source_hasher.raw_hash(), operation, error));
+    TEST_AND_RETURN_FALSE(ValidateSourceHash(source_hash, operation, error));
   }
 
-  DCHECK_EQ(bytes_read, static_cast<ssize_t>(blocks_to_read * block_size_));
   return true;
 }
 
@@ -1210,12 +1192,102 @@
     const uint64_t begin_byte =
         end_byte - (block_size_ - operation.dst_length() % block_size_);
     brillo::Blob zeros(end_byte - begin_byte);
-    TEST_AND_RETURN_FALSE(
-        utils::PWriteAll(target_fd_, zeros.data(), end_byte - begin_byte, begin_byte));
+    TEST_AND_RETURN_FALSE(utils::PWriteAll(
+        target_fd_, zeros.data(), end_byte - begin_byte, begin_byte));
   }
   return true;
 }
 
+bool DeltaPerformer::CalculateAndValidateSourceHash(
+    const InstallOperation& operation, ErrorCode* error) {
+  const uint64_t kMaxBlocksToRead = 256;  // 1MB if block size is 4KB
+  auto total_blocks = utils::BlocksInExtents(operation.src_extents());
+  brillo::Blob buf(std::min(kMaxBlocksToRead, total_blocks) * block_size_);
+  DirectExtentReader reader;
+  TEST_AND_RETURN_FALSE(
+      reader.Init(source_fd_, operation.src_extents(), block_size_));
+  HashCalculator source_hasher;
+  while (total_blocks > 0) {
+    auto read_blocks = std::min(total_blocks, kMaxBlocksToRead);
+    TEST_AND_RETURN_FALSE(reader.Read(buf.data(), read_blocks * block_size_));
+    TEST_AND_RETURN_FALSE(
+        source_hasher.Update(buf.data(), read_blocks * block_size_));
+    total_blocks -= read_blocks;
+  }
+  TEST_AND_RETURN_FALSE(source_hasher.Finalize());
+  TEST_AND_RETURN_FALSE(
+      ValidateSourceHash(source_hasher.raw_hash(), operation, error));
+  return true;
+}
+
+namespace {
+
+class BsdiffExtentFile : public bsdiff::FileInterface {
+ public:
+  BsdiffExtentFile(std::unique_ptr<ExtentReader> reader, size_t size)
+      : BsdiffExtentFile(std::move(reader), nullptr, size) {}
+  BsdiffExtentFile(std::unique_ptr<ExtentWriter> writer, size_t size)
+      : BsdiffExtentFile(nullptr, std::move(writer), size) {}
+
+  ~BsdiffExtentFile() override = default;
+
+  bool Read(void* buf, size_t count, size_t* bytes_read) override {
+    TEST_AND_RETURN_FALSE(reader_->Read(buf, count));
+    *bytes_read = count;
+    offset_ += count;
+    return true;
+  }
+
+  bool Write(const void* buf, size_t count, size_t* bytes_written) override {
+    TEST_AND_RETURN_FALSE(writer_->Write(buf, count));
+    *bytes_written = count;
+    offset_ += count;
+    return true;
+  }
+
+  bool Seek(off_t pos) override {
+    if (reader_ != nullptr) {
+      TEST_AND_RETURN_FALSE(reader_->Seek(pos));
+      offset_ = pos;
+    } else {
+      // For writes technically there should be no change of position, or it
+      // should be equivalent of current offset.
+      TEST_AND_RETURN_FALSE(offset_ == static_cast<uint64_t>(pos));
+    }
+    return true;
+  }
+
+  bool Close() override {
+    if (writer_ != nullptr) {
+      TEST_AND_RETURN_FALSE(writer_->End());
+    }
+    return true;
+  }
+
+  bool GetSize(uint64_t* size) override {
+    *size = size_;
+    return true;
+  }
+
+ private:
+  BsdiffExtentFile(std::unique_ptr<ExtentReader> reader,
+                   std::unique_ptr<ExtentWriter> writer,
+                   size_t size)
+      : reader_(std::move(reader)),
+        writer_(std::move(writer)),
+        size_(size),
+        offset_(0) {}
+
+  std::unique_ptr<ExtentReader> reader_;
+  std::unique_ptr<ExtentWriter> writer_;
+  uint64_t size_;
+  uint64_t offset_;
+
+  DISALLOW_COPY_AND_ASSIGN(BsdiffExtentFile);
+};
+
+}  // namespace
+
 bool DeltaPerformer::PerformSourceBsdiffOperation(
     const InstallOperation& operation, ErrorCode* error) {
   // Since we delete data off the beginning of the buffer as we use it,
@@ -1228,45 +1300,142 @@
     TEST_AND_RETURN_FALSE(operation.dst_length() % block_size_ == 0);
 
   if (operation.has_src_sha256_hash()) {
-    HashCalculator source_hasher;
-    const uint64_t kMaxBlocksToRead = 512;  // 2MB if block size is 4KB
-    brillo::Blob buf(kMaxBlocksToRead * block_size_);
-    for (const Extent& extent : operation.src_extents()) {
-      for (uint64_t i = 0; i < extent.num_blocks(); i += kMaxBlocksToRead) {
-        uint64_t blocks_to_read = min(
-            kMaxBlocksToRead, static_cast<uint64_t>(extent.num_blocks()) - i);
-        ssize_t bytes_to_read = blocks_to_read * block_size_;
-        ssize_t bytes_read_this_iteration = 0;
-        TEST_AND_RETURN_FALSE(
-            utils::PReadAll(source_fd_, buf.data(), bytes_to_read,
-                            (extent.start_block() + i) * block_size_,
-                            &bytes_read_this_iteration));
-        TEST_AND_RETURN_FALSE(bytes_read_this_iteration == bytes_to_read);
-        TEST_AND_RETURN_FALSE(source_hasher.Update(buf.data(), bytes_to_read));
-      }
-    }
-    TEST_AND_RETURN_FALSE(source_hasher.Finalize());
-    TEST_AND_RETURN_FALSE(
-        ValidateSourceHash(source_hasher.raw_hash(), operation, error));
+    TEST_AND_RETURN_FALSE(CalculateAndValidateSourceHash(operation, error));
   }
 
-  string input_positions;
-  TEST_AND_RETURN_FALSE(ExtentsToBsdiffPositionsString(operation.src_extents(),
-                                                       block_size_,
-                                                       operation.src_length(),
-                                                       &input_positions));
-  string output_positions;
-  TEST_AND_RETURN_FALSE(ExtentsToBsdiffPositionsString(operation.dst_extents(),
-                                                       block_size_,
-                                                       operation.dst_length(),
-                                                       &output_positions));
+  auto reader = std::make_unique<DirectExtentReader>();
+  TEST_AND_RETURN_FALSE(
+      reader->Init(source_fd_, operation.src_extents(), block_size_));
+  auto src_file = std::make_unique<BsdiffExtentFile>(
+      std::move(reader),
+      utils::BlocksInExtents(operation.src_extents()) * block_size_);
 
-  TEST_AND_RETURN_FALSE(bsdiff::bspatch(source_path_.c_str(),
-                                        target_path_.c_str(),
+  auto writer = std::make_unique<DirectExtentWriter>();
+  TEST_AND_RETURN_FALSE(
+      writer->Init(target_fd_, operation.dst_extents(), block_size_));
+  auto dst_file = std::make_unique<BsdiffExtentFile>(
+      std::move(writer),
+      utils::BlocksInExtents(operation.dst_extents()) * block_size_);
+
+  TEST_AND_RETURN_FALSE(bsdiff::bspatch(std::move(src_file),
+                                        std::move(dst_file),
                                         buffer_.data(),
-                                        buffer_.size(),
-                                        input_positions.c_str(),
-                                        output_positions.c_str()) == 0);
+                                        buffer_.size()) == 0);
+  DiscardBuffer(true, buffer_.size());
+  return true;
+}
+
+namespace {
+
+// A class to be passed to |puffpatch| for reading from |source_fd_| and writing
+// into |target_fd_|.
+class PuffinExtentStream : public puffin::StreamInterface {
+ public:
+  // Constructor for creating a stream for reading from an |ExtentReader|.
+  PuffinExtentStream(std::unique_ptr<ExtentReader> reader, size_t size)
+      : PuffinExtentStream(std::move(reader), nullptr, size) {}
+
+  // Constructor for creating a stream for writing to an |ExtentWriter|.
+  PuffinExtentStream(std::unique_ptr<ExtentWriter> writer, size_t size)
+      : PuffinExtentStream(nullptr, std::move(writer), size) {}
+
+  ~PuffinExtentStream() override = default;
+
+  bool GetSize(size_t* size) const override {
+    *size = size_;
+    return true;
+  }
+
+  bool GetOffset(size_t* offset) const override {
+    *offset = offset_;
+    return true;
+  }
+
+  bool Seek(size_t offset) override {
+    if (is_read_) {
+      TEST_AND_RETURN_FALSE(reader_->Seek(offset));
+      offset_ = offset;
+    } else {
+      // For writes technically there should be no change of position, or it
+      // should equivalent of current offset.
+      TEST_AND_RETURN_FALSE(offset_ == offset);
+    }
+    return true;
+  }
+
+  bool Read(void* buffer, size_t count) override {
+    TEST_AND_RETURN_FALSE(is_read_);
+    TEST_AND_RETURN_FALSE(reader_->Read(buffer, count));
+    offset_ += count;
+    return true;
+  }
+
+  bool Write(const void* buffer, size_t count) override {
+    TEST_AND_RETURN_FALSE(!is_read_);
+    TEST_AND_RETURN_FALSE(writer_->Write(buffer, count));
+    offset_ += count;
+    return true;
+  }
+
+  bool Close() override {
+    if (!is_read_) {
+      TEST_AND_RETURN_FALSE(writer_->End());
+    }
+    return true;
+  }
+
+ private:
+  PuffinExtentStream(std::unique_ptr<ExtentReader> reader,
+                     std::unique_ptr<ExtentWriter> writer,
+                     size_t size)
+      : reader_(std::move(reader)),
+        writer_(std::move(writer)),
+        size_(size),
+        offset_(0),
+        is_read_(reader_ ? true : false) {}
+
+  std::unique_ptr<ExtentReader> reader_;
+  std::unique_ptr<ExtentWriter> writer_;
+  uint64_t size_;
+  uint64_t offset_;
+  bool is_read_;
+
+  DISALLOW_COPY_AND_ASSIGN(PuffinExtentStream);
+};
+
+}  // namespace
+
+bool DeltaPerformer::PerformPuffDiffOperation(const InstallOperation& operation,
+                                              ErrorCode* error) {
+  // Since we delete data off the beginning of the buffer as we use it,
+  // the data we need should be exactly at the beginning of the buffer.
+  TEST_AND_RETURN_FALSE(buffer_offset_ == operation.data_offset());
+  TEST_AND_RETURN_FALSE(buffer_.size() >= operation.data_length());
+
+  if (operation.has_src_sha256_hash()) {
+    TEST_AND_RETURN_FALSE(CalculateAndValidateSourceHash(operation, error));
+  }
+
+  auto reader = std::make_unique<DirectExtentReader>();
+  TEST_AND_RETURN_FALSE(
+      reader->Init(source_fd_, operation.src_extents(), block_size_));
+  puffin::UniqueStreamPtr src_stream(new PuffinExtentStream(
+      std::move(reader),
+      utils::BlocksInExtents(operation.src_extents()) * block_size_));
+
+  auto writer = std::make_unique<DirectExtentWriter>();
+  TEST_AND_RETURN_FALSE(
+      writer->Init(target_fd_, operation.dst_extents(), block_size_));
+  puffin::UniqueStreamPtr dst_stream(new PuffinExtentStream(
+      std::move(writer),
+      utils::BlocksInExtents(operation.dst_extents()) * block_size_));
+
+  const size_t kMaxCacheSize = 5 * 1024 * 1024;  // Total 5MB cache.
+  TEST_AND_RETURN_FALSE(puffin::PuffPatch(std::move(src_stream),
+                                          std::move(dst_stream),
+                                          buffer_.data(),
+                                          buffer_.size(),
+                                          kMaxCacheSize));
   DiscardBuffer(true, buffer_.size());
   return true;
 }
@@ -1695,6 +1864,7 @@
     prefs->SetInt64(kPrefsManifestMetadataSize, -1);
     prefs->SetInt64(kPrefsManifestSignatureSize, -1);
     prefs->SetInt64(kPrefsResumedUpdateFailures, 0);
+    prefs->Delete(kPrefsPostInstallSucceeded);
   }
   return true;
 }
diff --git a/payload_consumer/delta_performer.h b/payload_consumer/delta_performer.h
index f363a4c..731e7f1 100644
--- a/payload_consumer/delta_performer.h
+++ b/payload_consumer/delta_performer.h
@@ -19,6 +19,7 @@
 
 #include <inttypes.h>
 
+#include <limits>
 #include <string>
 #include <vector>
 
@@ -79,13 +80,15 @@
                  HardwareInterface* hardware,
                  DownloadActionDelegate* download_delegate,
                  InstallPlan* install_plan,
-                 InstallPlan::Payload* payload)
+                 InstallPlan::Payload* payload,
+                 bool is_interactive)
       : prefs_(prefs),
         boot_control_(boot_control),
         hardware_(hardware),
         download_delegate_(download_delegate),
         install_plan_(install_plan),
-        payload_(payload) {}
+        payload_(payload),
+        is_interactive_(is_interactive) {}
 
   // FileWriter's Write implementation where caller doesn't care about
   // error codes.
@@ -162,9 +165,9 @@
     public_key_path_ = public_key_path;
   }
 
-  // Set |*out_offset| to the byte offset where the size of the metadata signature
-  // is stored in a payload. Return true on success, if this field is not
-  // present in the payload, return false.
+  // Set |*out_offset| to the byte offset where the size of the metadata
+  // signature is stored in a payload. Return true on success, if this field is
+  // not present in the payload, return false.
   bool GetMetadataSignatureSizeOffset(uint64_t* out_offset) const;
 
   // Set |*out_offset| to the byte offset at which the manifest protobuf begins
@@ -242,6 +245,10 @@
   // buffer.
   ErrorCode ValidateMetadataSignature(const brillo::Blob& payload);
 
+  // Calculates and validates the source hash of the operation |operation|.
+  bool CalculateAndValidateSourceHash(const InstallOperation& operation,
+                                      ErrorCode* error);
+
   // Returns true on success.
   bool PerformInstallOperation(const InstallOperation& operation);
 
@@ -256,6 +263,8 @@
                                   ErrorCode* error);
   bool PerformSourceBsdiffOperation(const InstallOperation& operation,
                                     ErrorCode* error);
+  bool PerformPuffDiffOperation(const InstallOperation& operation,
+                                ErrorCode* error);
 
   // Extracts the payload signature message from the blob on the |operation| if
   // the offset matches the one specified by the manifest. Returns whether the
@@ -390,6 +399,9 @@
   // The last progress chunk recorded.
   unsigned last_progress_chunk_{0};
 
+  // If |true|, the update is user initiated (vs. periodic update checks).
+  bool is_interactive_{false};
+
   // The timeout after which we should force emitting a progress log (constant),
   // and the actual point in time for the next forced log to be emitted.
   const base::TimeDelta forced_progress_log_wait_{
diff --git a/payload_consumer/delta_performer_integration_test.cc b/payload_consumer/delta_performer_integration_test.cc
index bc67d93..3572a6d 100644
--- a/payload_consumer/delta_performer_integration_test.cc
+++ b/payload_consumer/delta_performer_integration_test.cc
@@ -747,7 +747,8 @@
                                   &state->fake_hardware_,
                                   &state->mock_delegate_,
                                   install_plan,
-                                  &install_plan->payloads[0]);
+                                  &install_plan->payloads[0],
+                                  false /* is_interactive */);
   string public_key_path = GetBuildArtifactsPath(kUnittestPublicKeyPath);
   EXPECT_TRUE(utils::FileExists(public_key_path.c_str()));
   (*performer)->set_public_key_path(public_key_path);
diff --git a/payload_consumer/delta_performer_unittest.cc b/payload_consumer/delta_performer_unittest.cc
index fbdf1ab..420efd2 100644
--- a/payload_consumer/delta_performer_unittest.cc
+++ b/payload_consumer/delta_performer_unittest.cc
@@ -87,6 +87,61 @@
     0x00, 0x00, 0x59, 0x5a,
 };
 
+const uint8_t src_deflates[] = {
+  /* raw      0  */ 0x11, 0x22,
+  /* deflate  2  */ 0x63, 0x64, 0x62, 0x66, 0x61, 0x05, 0x00,
+  /* raw      9  */ 0x33,
+  /* deflate  10 */ 0x03, 0x00,
+  /* raw      12 */
+  /* deflate  12 */ 0x63, 0x04, 0x00,
+  /* raw      15 */ 0x44, 0x55
+};
+
+const uint8_t dst_deflates[] = {
+  /* deflate  0  */ 0x63, 0x64, 0x62, 0x66, 0x61, 0x05, 0x00,
+  /* raw      7  */ 0x33, 0x66,
+  /* deflate  9  */ 0x01, 0x05, 0x00, 0xFA, 0xFF, 0x01, 0x02, 0x03, 0x04, 0x05,
+  /* deflate  19 */ 0x63, 0x04, 0x00
+};
+
+// To generate this patch either:
+// - Use puffin/src/patching_unittest.cc:TestPatching
+// Or
+// - Use the following approach:
+// * Make src_deflate a string of hex with only spaces. (e.g. "0XTE 0xST")
+// * echo "0XTE 0xST" | xxd -r -p > src.bin
+// * Find the location of deflates in src_deflates (in bytes) in the format of
+//   "offset:length,...". (e.g. "2:7,10:2,12:3")
+// * Do previous three steps for dst_deflates.
+// * puffin --operation=puffdiff --src_file=src.bin --dst_file=dst.bin \
+//   --src_deflates_byte="2:7,10:2,12:3" --dst_deflates_byte="0:7,9:10,19:3" \
+//   --patch_file=patch.bin
+// * hexdump -ve '"  " 12/1 "0x%02x, " "\n"' patch.bin
+const uint8_t puffdiff_patch[] = {
+  0x50, 0x55, 0x46, 0x31, 0x00, 0x00, 0x00, 0x51, 0x08, 0x01, 0x12, 0x27,
+  0x0A, 0x04, 0x08, 0x10, 0x10, 0x32, 0x0A, 0x04, 0x08, 0x50, 0x10, 0x0A,
+  0x0A, 0x04, 0x08, 0x60, 0x10, 0x12, 0x12, 0x04, 0x08, 0x10, 0x10, 0x58,
+  0x12, 0x04, 0x08, 0x78, 0x10, 0x28, 0x12, 0x05, 0x08, 0xA8, 0x01, 0x10,
+  0x38, 0x18, 0x1F, 0x1A, 0x24, 0x0A, 0x02, 0x10, 0x32, 0x0A, 0x04, 0x08,
+  0x48, 0x10, 0x50, 0x0A, 0x05, 0x08, 0x98, 0x01, 0x10, 0x12, 0x12, 0x02,
+  0x10, 0x58, 0x12, 0x04, 0x08, 0x70, 0x10, 0x58, 0x12, 0x05, 0x08, 0xC8,
+  0x01, 0x10, 0x38, 0x18, 0x21, 0x42, 0x53, 0x44, 0x49, 0x46, 0x46, 0x34,
+  0x30, 0x38, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x34, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x21, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x42, 0x5A, 0x68, 0x39, 0x31, 0x41, 0x59, 0x26, 0x53, 0x59, 0x65,
+  0x29, 0x8C, 0x9B, 0x00, 0x00, 0x03, 0x60, 0x40, 0x7A, 0x0E, 0x08, 0x00,
+  0x40, 0x00, 0x20, 0x00, 0x21, 0x22, 0x9A, 0x3D, 0x4F, 0x50, 0x40, 0x0C,
+  0x3B, 0xC7, 0x9B, 0xB2, 0x21, 0x0E, 0xE9, 0x15, 0x98, 0x7A, 0x7C, 0x5D,
+  0xC9, 0x14, 0xE1, 0x42, 0x41, 0x94, 0xA6, 0x32, 0x6C, 0x42, 0x5A, 0x68,
+  0x39, 0x31, 0x41, 0x59, 0x26, 0x53, 0x59, 0xF1, 0x20, 0x5F, 0x0D, 0x00,
+  0x00, 0x02, 0x41, 0x15, 0x42, 0x08, 0x20, 0x00, 0x40, 0x00, 0x00, 0x02,
+  0x40, 0x00, 0x20, 0x00, 0x22, 0x3D, 0x23, 0x10, 0x86, 0x03, 0x96, 0x54,
+  0x11, 0x16, 0x5F, 0x17, 0x72, 0x45, 0x38, 0x50, 0x90, 0xF1, 0x20, 0x5F,
+  0x0D, 0x42, 0x5A, 0x68, 0x39, 0x31, 0x41, 0x59, 0x26, 0x53, 0x59, 0x07,
+  0xD4, 0xCB, 0x6E, 0x00, 0x00, 0x00, 0x01, 0x00, 0x01, 0x00, 0x20, 0x00,
+  0x21, 0x18, 0x46, 0x82, 0xEE, 0x48, 0xA7, 0x0A, 0x12, 0x00, 0xFA, 0x99,
+  0x6D, 0xC0};
+
 }  // namespace
 
 class DeltaPerformerTest : public ::testing::Test {
@@ -334,7 +389,8 @@
                             &fake_hardware_,
                             &mock_delegate_,
                             &install_plan_,
-                            &payload_};
+                            &payload_,
+                            false /* is_interactive*/};
 };
 
 TEST_F(DeltaPerformerTest, FullPayloadWriteTest) {
@@ -375,7 +431,7 @@
   testing::Mock::VerifyAndClearExpectations(&mock_delegate_);
   EXPECT_CALL(mock_delegate_, ShouldCancel(_))
       .WillOnce(
-          testing::DoAll(testing::SetArgumentPointee<0>(ErrorCode::kError),
+          testing::DoAll(testing::SetArgPointee<0>(ErrorCode::kError),
                          testing::Return(true)));
 
   ApplyPayload(payload_data, "/dev/null", false);
@@ -485,6 +541,32 @@
   EXPECT_EQ(expected_data, ApplyPayload(payload_data, source_path, true));
 }
 
+TEST_F(DeltaPerformerTest, PuffdiffOperationTest) {
+  AnnotatedOperation aop;
+  *(aop.op.add_src_extents()) = ExtentForRange(0, 1);
+  *(aop.op.add_dst_extents()) = ExtentForRange(0, 1);
+  brillo::Blob puffdiff_payload(std::begin(puffdiff_patch),
+                                std::end(puffdiff_patch));
+  aop.op.set_data_offset(0);
+  aop.op.set_data_length(puffdiff_payload.size());
+  aop.op.set_type(InstallOperation::PUFFDIFF);
+  brillo::Blob src(std::begin(src_deflates), std::end(src_deflates));
+  src.resize(4096);  // block size
+  brillo::Blob src_hash;
+  EXPECT_TRUE(HashCalculator::RawHashOfData(src, &src_hash));
+  aop.op.set_src_sha256_hash(src_hash.data(), src_hash.size());
+
+  brillo::Blob payload_data = GeneratePayload(puffdiff_payload, {aop}, false);
+
+  string source_path;
+  EXPECT_TRUE(utils::MakeTempFile("Source-XXXXXX", &source_path, nullptr));
+  ScopedPathUnlinker path_unlinker(source_path);
+  EXPECT_TRUE(utils::WriteFile(source_path.c_str(), src.data(), src.size()));
+
+  brillo::Blob dst(std::begin(dst_deflates), std::end(dst_deflates));
+  EXPECT_EQ(dst, ApplyPayload(payload_data, source_path, true));
+}
+
 TEST_F(DeltaPerformerTest, SourceHashMismatchTest) {
   brillo::Blob expected_data = {'f', 'o', 'o'};
   brillo::Blob actual_data = {'b', 'a', 'r'};
@@ -766,8 +848,8 @@
 
   base::ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
-  string non_existing_file = temp_dir.path().Append("non-existing").value();
-  string existing_file = temp_dir.path().Append("existing").value();
+  string non_existing_file = temp_dir.GetPath().Append("non-existing").value();
+  string existing_file = temp_dir.GetPath().Append("existing").value();
   EXPECT_EQ(0, System(base::StringPrintf("touch %s", existing_file.c_str())));
 
   // Non-official build, non-existing public-key, key in response -> true
@@ -832,20 +914,4 @@
   EXPECT_EQ(DeltaPerformer::kSupportedMajorPayloadVersion, major_version);
 }
 
-// Test that we recognize our own zlib compressor implementation as supported.
-// All other equivalent implementations should be added to
-// kCompatibleZlibFingerprint.
-TEST_F(DeltaPerformerTest, ZlibFingerprintMatch) {
-  string fingerprint;
-#ifdef __ANDROID__
-  const std::string kZlibFingerprintPath =
-      test_utils::GetBuildArtifactsPath("zlib_fingerprint");
-#else
-  const std::string kZlibFingerprintPath = "/etc/zlib_fingerprint";
-#endif  // __ANDROID__
-  EXPECT_TRUE(base::ReadFileToString(base::FilePath(kZlibFingerprintPath),
-                                     &fingerprint));
-  EXPECT_TRUE(utils::IsZlibCompatible(fingerprint));
-}
-
 }  // namespace chromeos_update_engine
diff --git a/payload_consumer/download_action.cc b/payload_consumer/download_action.cc
index c3a5016..f1b6e33 100644
--- a/payload_consumer/download_action.cc
+++ b/payload_consumer/download_action.cc
@@ -20,9 +20,10 @@
 
 #include <algorithm>
 #include <string>
-#include <vector>
 
 #include <base/files/file_path.h>
+#include <base/metrics/statistics_recorder.h>
+#include <base/strings/stringprintf.h>
 
 #include "update_engine/common/action_pipe.h"
 #include "update_engine/common/boot_control_interface.h"
@@ -35,7 +36,6 @@
 
 using base::FilePath;
 using std::string;
-using std::vector;
 
 namespace chromeos_update_engine {
 
@@ -43,17 +43,21 @@
                                BootControlInterface* boot_control,
                                HardwareInterface* hardware,
                                SystemState* system_state,
-                               HttpFetcher* http_fetcher)
+                               HttpFetcher* http_fetcher,
+                               bool is_interactive)
     : prefs_(prefs),
       boot_control_(boot_control),
       hardware_(hardware),
       system_state_(system_state),
       http_fetcher_(new MultiRangeHttpFetcher(http_fetcher)),
+      is_interactive_(is_interactive),
       writer_(nullptr),
       code_(ErrorCode::kSuccess),
       delegate_(nullptr),
       p2p_sharing_fd_(-1),
-      p2p_visible_(true) {}
+      p2p_visible_(true) {
+  base::StatisticsRecorder::Initialize();
+}
 
 DownloadAction::~DownloadAction() {}
 
@@ -173,6 +177,7 @@
   install_plan_.Dump();
 
   bytes_received_ = 0;
+  bytes_received_previous_payloads_ = 0;
   bytes_total_ = 0;
   for (const auto& payload : install_plan_.payloads)
     bytes_total_ += payload.size;
@@ -240,8 +245,13 @@
   if (writer_ && writer_ != delta_performer_.get()) {
     LOG(INFO) << "Using writer for test.";
   } else {
-    delta_performer_.reset(new DeltaPerformer(
-        prefs_, boot_control_, hardware_, delegate_, &install_plan_, payload_));
+    delta_performer_.reset(new DeltaPerformer(prefs_,
+                                              boot_control_,
+                                              hardware_,
+                                              delegate_,
+                                              &install_plan_,
+                                              payload_,
+                                              is_interactive_));
     writer_ = delta_performer_.get();
   }
   if (system_state_ != nullptr) {
@@ -317,8 +327,10 @@
   }
 
   bytes_received_ += length;
+  uint64_t bytes_downloaded_total =
+      bytes_received_previous_payloads_ + bytes_received_;
   if (delegate_ && download_active_) {
-    delegate_->BytesReceived(length, bytes_received_, bytes_total_);
+    delegate_->BytesReceived(length, bytes_downloaded_total, bytes_total_);
   }
   if (writer_ && !writer_->Write(bytes, length, &code_)) {
     if (code_ != ErrorCode::kSuccess) {
@@ -349,31 +361,44 @@
 void DownloadAction::TransferComplete(HttpFetcher* fetcher, bool successful) {
   if (writer_) {
     LOG_IF(WARNING, writer_->Close() != 0) << "Error closing the writer.";
-    writer_ = nullptr;
+    if (delta_performer_.get() == writer_) {
+      // no delta_performer_ in tests, so leave the test writer in place
+      writer_ = nullptr;
+    }
   }
   download_active_ = false;
   ErrorCode code =
       successful ? ErrorCode::kSuccess : ErrorCode::kDownloadTransferError;
-  if (code == ErrorCode::kSuccess && delta_performer_.get()) {
-    if (!payload_->already_applied)
+  if (code == ErrorCode::kSuccess) {
+    if (delta_performer_ && !payload_->already_applied)
       code = delta_performer_->VerifyPayload(payload_->hash, payload_->size);
-    if (code != ErrorCode::kSuccess) {
+    if (code == ErrorCode::kSuccess) {
+      if (payload_ < &install_plan_.payloads.back() &&
+                 system_state_->payload_state()->NextPayload()) {
+        LOG(INFO) << "Incrementing to next payload";
+        // No need to reset if this payload was already applied.
+        if (delta_performer_ && !payload_->already_applied)
+          DeltaPerformer::ResetUpdateProgress(prefs_, false);
+        // Start downloading next payload.
+        bytes_received_previous_payloads_ += payload_->size;
+        payload_++;
+        install_plan_.download_url =
+            system_state_->payload_state()->GetCurrentUrl();
+        StartDownloading();
+        return;
+      }
+      // Log UpdateEngine.DownloadAction.* histograms to help diagnose
+      // long-blocking oeprations.
+      std::string histogram_output;
+      base::StatisticsRecorder::WriteGraph(
+          "UpdateEngine.DownloadAction.", &histogram_output);
+      LOG(INFO) << histogram_output;
+    } else {
       LOG(ERROR) << "Download of " << install_plan_.download_url
                  << " failed due to payload verification error.";
       // Delete p2p file, if applicable.
       if (!p2p_file_id_.empty())
         CloseP2PSharingFd(true);
-    } else if (payload_ < &install_plan_.payloads.back() &&
-               system_state_->payload_state()->NextPayload()) {
-      // No need to reset if this payload was already applied.
-      if (!payload_->already_applied)
-        DeltaPerformer::ResetUpdateProgress(prefs_, false);
-      // Start downloading next payload.
-      payload_++;
-      install_plan_.download_url =
-          system_state_->payload_state()->GetCurrentUrl();
-      StartDownloading();
-      return;
     }
   }
 
diff --git a/payload_consumer/download_action.h b/payload_consumer/download_action.h
index d0e6000..81d7333 100644
--- a/payload_consumer/download_action.h
+++ b/payload_consumer/download_action.h
@@ -73,12 +73,13 @@
   // Takes ownership of the passed in HttpFetcher. Useful for testing.
   // A good calling pattern is:
   // DownloadAction(prefs, boot_contol, hardware, system_state,
-  //                new WhateverHttpFetcher);
+  //                new WhateverHttpFetcher, false);
   DownloadAction(PrefsInterface* prefs,
                  BootControlInterface* boot_control,
                  HardwareInterface* hardware,
                  SystemState* system_state,
-                 HttpFetcher* http_fetcher);
+                 HttpFetcher* http_fetcher,
+                 bool is_interactive);
   ~DownloadAction() override;
 
   // InstallPlanAction overrides.
@@ -154,6 +155,11 @@
   // Pointer to the MultiRangeHttpFetcher that does the http work.
   std::unique_ptr<MultiRangeHttpFetcher> http_fetcher_;
 
+  // If |true|, the update is user initiated (vs. periodic update checks). Hence
+  // the |delta_performer_| can decide not to use O_DSYNC flag for faster
+  // update.
+  bool is_interactive_;
+
   // The FileWriter that downloaded data should be written to. It will
   // either point to *decompressing_file_writer_ or *delta_performer_.
   FileWriter* writer_;
@@ -166,7 +172,8 @@
 
   // For reporting status to outsiders
   DownloadActionDelegate* delegate_;
-  uint64_t bytes_received_{0};
+  uint64_t bytes_received_{0};  // per file/range
+  uint64_t bytes_received_previous_payloads_{0};
   uint64_t bytes_total_{0};
   bool download_active_{false};
 
diff --git a/payload_consumer/download_action_unittest.cc b/payload_consumer/download_action_unittest.cc
index 7d3ac6c..21ce461 100644
--- a/payload_consumer/download_action_unittest.cc
+++ b/payload_consumer/download_action_unittest.cc
@@ -22,14 +22,12 @@
 #include <memory>
 #include <string>
 #include <utility>
-#include <vector>
 
 #include <base/bind.h>
 #include <base/files/file_path.h>
 #include <base/files/file_util.h>
 #include <base/location.h>
 #include <base/strings/stringprintf.h>
-#include <brillo/bind_lambda.h>
 #include <brillo/message_loops/fake_message_loop.h>
 #include <brillo/message_loops/message_loop.h>
 
@@ -41,6 +39,7 @@
 #include "update_engine/common/utils.h"
 #include "update_engine/fake_p2p_manager_configuration.h"
 #include "update_engine/fake_system_state.h"
+#include "update_engine/mock_file_writer.h"
 #include "update_engine/payload_consumer/mock_download_action.h"
 #include "update_engine/update_manager/fake_update_manager.h"
 
@@ -51,11 +50,11 @@
 using base::WriteFile;
 using std::string;
 using std::unique_ptr;
-using std::vector;
 using test_utils::ScopedTempFile;
 using testing::AtLeast;
 using testing::InSequence;
 using testing::Return;
+using testing::SetArgPointee;
 using testing::_;
 
 class DownloadActionTest : public ::testing::Test { };
@@ -165,7 +164,8 @@
                                  fake_system_state.boot_control(),
                                  fake_system_state.hardware(),
                                  &fake_system_state,
-                                 http_fetcher);
+                                 http_fetcher,
+                                 false /* is_interactive */);
   download_action.SetTestFileWriter(&writer);
   BondActions(&feeder_action, &download_action);
   MockDownloadActionDelegate download_delegate;
@@ -242,6 +242,93 @@
                false);  // use_download_delegate
 }
 
+TEST(DownloadActionTest, MultiPayloadProgressTest) {
+  std::vector<brillo::Blob> payload_datas;
+  // the first payload must be the largest, as it's the actual payload used by
+  // the MockHttpFetcher for all downloaded data.
+  payload_datas.emplace_back(4 * kMockHttpFetcherChunkSize + 256);
+  payload_datas.emplace_back(2 * kMockHttpFetcherChunkSize);
+  brillo::FakeMessageLoop loop(nullptr);
+  loop.SetAsCurrent();
+  FakeSystemState fake_system_state;
+  EXPECT_CALL(*fake_system_state.mock_payload_state(), NextPayload())
+      .WillOnce(Return(true));
+
+  MockFileWriter mock_file_writer;
+  EXPECT_CALL(mock_file_writer, Close()).WillRepeatedly(Return(0));
+  EXPECT_CALL(mock_file_writer, Write(_, _, _))
+      .WillRepeatedly(
+          DoAll(SetArgPointee<2>(ErrorCode::kSuccess), Return(true)));
+
+  InstallPlan install_plan;
+  uint64_t total_expected_download_size{0};
+  for (const auto& data : payload_datas) {
+    uint64_t size = data.size();
+    install_plan.payloads.push_back(
+        {.size = size, .type = InstallPayloadType::kFull});
+    total_expected_download_size += size;
+  }
+  ObjectFeederAction<InstallPlan> feeder_action;
+  feeder_action.set_obj(install_plan);
+  MockPrefs prefs;
+  MockHttpFetcher* http_fetcher = new MockHttpFetcher(
+      payload_datas[0].data(), payload_datas[0].size(), nullptr);
+  // takes ownership of passed in HttpFetcher
+  DownloadAction download_action(&prefs,
+                                 fake_system_state.boot_control(),
+                                 fake_system_state.hardware(),
+                                 &fake_system_state,
+                                 http_fetcher,
+                                 false /* is_interactive */);
+  download_action.SetTestFileWriter(&mock_file_writer);
+  BondActions(&feeder_action, &download_action);
+  MockDownloadActionDelegate download_delegate;
+  {
+    InSequence s;
+    download_action.set_delegate(&download_delegate);
+    // these are hand-computed based on the payloads specified above
+    EXPECT_CALL(download_delegate,
+                BytesReceived(kMockHttpFetcherChunkSize,
+                              kMockHttpFetcherChunkSize,
+                              total_expected_download_size));
+    EXPECT_CALL(download_delegate,
+                BytesReceived(kMockHttpFetcherChunkSize,
+                              kMockHttpFetcherChunkSize * 2,
+                              total_expected_download_size));
+    EXPECT_CALL(download_delegate,
+                BytesReceived(kMockHttpFetcherChunkSize,
+                              kMockHttpFetcherChunkSize * 3,
+                              total_expected_download_size));
+    EXPECT_CALL(download_delegate,
+                BytesReceived(kMockHttpFetcherChunkSize,
+                              kMockHttpFetcherChunkSize * 4,
+                              total_expected_download_size));
+    EXPECT_CALL(download_delegate,
+                BytesReceived(256,
+                              kMockHttpFetcherChunkSize * 4 + 256,
+                              total_expected_download_size));
+    EXPECT_CALL(download_delegate,
+                BytesReceived(kMockHttpFetcherChunkSize,
+                              kMockHttpFetcherChunkSize * 5 + 256,
+                              total_expected_download_size));
+    EXPECT_CALL(download_delegate,
+                BytesReceived(kMockHttpFetcherChunkSize,
+                              total_expected_download_size,
+                              total_expected_download_size));
+  }
+  ActionProcessor processor;
+  processor.EnqueueAction(&feeder_action);
+  processor.EnqueueAction(&download_action);
+
+  loop.PostTask(
+      FROM_HERE,
+      base::Bind(
+          [](ActionProcessor* processor) { processor->StartProcessing(); },
+          base::Unretained(&processor)));
+  loop.Run();
+  EXPECT_FALSE(loop.PendingTasks());
+}
+
 namespace {
 class TerminateEarlyTestProcessorDelegate : public ActionProcessorDelegate {
  public:
@@ -281,7 +368,8 @@
         fake_system_state_.boot_control(),
         fake_system_state_.hardware(),
         &fake_system_state_,
-        new MockHttpFetcher(data.data(), data.size(), nullptr));
+        new MockHttpFetcher(data.data(), data.size(), nullptr),
+        false /* is_interactive */);
     download_action.SetTestFileWriter(&writer);
     MockDownloadActionDelegate download_delegate;
     if (use_download_delegate) {
@@ -382,7 +470,8 @@
                                  fake_system_state_.boot_control(),
                                  fake_system_state_.hardware(),
                                  &fake_system_state_,
-                                 new MockHttpFetcher("x", 1, nullptr));
+                                 new MockHttpFetcher("x", 1, nullptr),
+                                 false /* is_interactive */);
   download_action.SetTestFileWriter(&writer);
 
   DownloadActionTestAction test_action;
@@ -471,7 +560,8 @@
                                               fake_system_state_.boot_control(),
                                               fake_system_state_.hardware(),
                                               &fake_system_state_,
-                                              http_fetcher_));
+                                              http_fetcher_,
+                                              false /* is_interactive */));
     download_action_->SetTestFileWriter(&writer);
     BondActions(&feeder_action, download_action_.get());
     DownloadActionTestProcessorDelegate delegate(ErrorCode::kSuccess);
diff --git a/payload_consumer/extent_reader.cc b/payload_consumer/extent_reader.cc
new file mode 100644
index 0000000..96ea918
--- /dev/null
+++ b/payload_consumer/extent_reader.cc
@@ -0,0 +1,98 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/payload_consumer/extent_reader.h"
+
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "update_engine/common/utils.h"
+#include "update_engine/payload_consumer/payload_constants.h"
+
+using google::protobuf::RepeatedPtrField;
+
+namespace chromeos_update_engine {
+
+bool DirectExtentReader::Init(FileDescriptorPtr fd,
+                              const RepeatedPtrField<Extent>& extents,
+                              uint32_t block_size) {
+  fd_ = fd;
+  extents_ = extents;
+  block_size_ = block_size;
+  cur_extent_ = extents_.begin();
+
+  extents_upper_bounds_.reserve(extents_.size() + 1);
+  // We add this pad as the first element to not bother with boundary checks
+  // later.
+  extents_upper_bounds_.emplace_back(0);
+  for (const auto& extent : extents_) {
+    total_size_ += extent.num_blocks() * block_size_;
+    extents_upper_bounds_.emplace_back(total_size_);
+  }
+  return true;
+}
+
+bool DirectExtentReader::Seek(uint64_t offset) {
+  TEST_AND_RETURN_FALSE(offset <= total_size_);
+  if (offset_ == offset) {
+    return true;
+  }
+  // The first item is zero and upper_bound never returns it because it always
+  // return the item which is greater than the given value.
+  auto extent_idx = std::upper_bound(
+      extents_upper_bounds_.begin(), extents_upper_bounds_.end(), offset) -
+      extents_upper_bounds_.begin() - 1;
+  cur_extent_ = std::next(extents_.begin(), extent_idx);
+  offset_ = offset;
+  cur_extent_bytes_read_ = offset_ - extents_upper_bounds_[extent_idx];
+  return true;
+}
+
+bool DirectExtentReader::Read(void* buffer, size_t count) {
+  auto bytes = reinterpret_cast<uint8_t*>(buffer);
+  uint64_t bytes_read = 0;
+  while (bytes_read < count) {
+    if (cur_extent_ == extents_.end()) {
+      TEST_AND_RETURN_FALSE(bytes_read == count);
+    }
+    uint64_t cur_extent_bytes_left =
+        cur_extent_->num_blocks() * block_size_ - cur_extent_bytes_read_;
+    uint64_t bytes_to_read =
+        std::min(count - bytes_read, cur_extent_bytes_left);
+
+    ssize_t out_bytes_read;
+    TEST_AND_RETURN_FALSE(utils::PReadAll(
+        fd_,
+        bytes + bytes_read,
+        bytes_to_read,
+        cur_extent_->start_block() * block_size_ + cur_extent_bytes_read_,
+        &out_bytes_read));
+    TEST_AND_RETURN_FALSE(out_bytes_read ==
+                          static_cast<ssize_t>(bytes_to_read));
+
+    bytes_read += bytes_to_read;
+    cur_extent_bytes_read_ += bytes_to_read;
+    offset_ += bytes_to_read;
+    if (cur_extent_bytes_read_ == cur_extent_->num_blocks() * block_size_) {
+      // We have to advance the cur_extent_;
+      cur_extent_++;
+      cur_extent_bytes_read_ = 0;
+    }
+  }
+  return true;
+}
+
+}  // namespace chromeos_update_engine
diff --git a/payload_consumer/extent_reader.h b/payload_consumer/extent_reader.h
new file mode 100644
index 0000000..3f9e4c8
--- /dev/null
+++ b/payload_consumer/extent_reader.h
@@ -0,0 +1,82 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_PAYLOAD_CONSUMER_EXTENT_READER_H_
+#define UPDATE_ENGINE_PAYLOAD_CONSUMER_EXTENT_READER_H_
+
+#include <vector>
+
+#include "update_engine/payload_consumer/file_descriptor.h"
+#include "update_engine/update_metadata.pb.h"
+
+namespace chromeos_update_engine {
+
+// ExtentReader is an abstract class with reads from a given file descriptor at
+// the extents given.
+class ExtentReader {
+ public:
+  virtual ~ExtentReader() = default;
+
+  // Initializes |ExtentReader|
+  virtual bool Init(FileDescriptorPtr fd,
+                    const google::protobuf::RepeatedPtrField<Extent>& extents,
+                    uint32_t block_size) = 0;
+
+  // Seeks to the given |offset| assuming all extents are concatenated together.
+  virtual bool Seek(uint64_t offset) = 0;
+
+  // Returns true on success.
+  virtual bool Read(void* buffer, size_t count) = 0;
+};
+
+// DirectExtentReader is probably the simplest ExtentReader implementation.
+// It reads the data directly from the extents.
+class DirectExtentReader : public ExtentReader {
+ public:
+  DirectExtentReader() = default;
+  ~DirectExtentReader() override = default;
+
+  bool Init(FileDescriptorPtr fd,
+            const google::protobuf::RepeatedPtrField<Extent>& extents,
+            uint32_t block_size) override;
+  bool Seek(uint64_t offset) override;
+  bool Read(void* bytes, size_t count) override;
+
+ private:
+  FileDescriptorPtr fd_{nullptr};
+  google::protobuf::RepeatedPtrField<Extent> extents_;
+  size_t block_size_{0};
+
+  // Current extent being read from |fd_|.
+  google::protobuf::RepeatedPtrField<Extent>::iterator cur_extent_;
+
+  // Bytes read from |cur_extent_| thus far.
+  uint64_t cur_extent_bytes_read_{0};
+
+  // Offset assuming all extents are concatenated.
+  uint64_t offset_{0};
+
+  // The accelaring upper bounds for |extents_| if we assume all extents are
+  // concatenated.
+  std::vector<uint64_t> extents_upper_bounds_;
+  uint64_t total_size_{0};
+
+  DISALLOW_COPY_AND_ASSIGN(DirectExtentReader);
+};
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_PAYLOAD_CONSUMER_EXTENT_READER_H_
diff --git a/payload_consumer/extent_reader_unittest.cc b/payload_consumer/extent_reader_unittest.cc
new file mode 100644
index 0000000..b7059bc
--- /dev/null
+++ b/payload_consumer/extent_reader_unittest.cc
@@ -0,0 +1,170 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/payload_consumer/extent_reader.h"
+
+#include <fcntl.h>
+
+#include <algorithm>
+#include <string>
+#include <vector>
+
+#include <brillo/secure_blob.h>
+#include <gtest/gtest.h>
+
+#include "update_engine/common/test_utils.h"
+#include "update_engine/common/utils.h"
+#include "update_engine/payload_consumer/file_descriptor.h"
+#include "update_engine/payload_consumer/payload_constants.h"
+#include "update_engine/payload_generator/extent_ranges.h"
+#include "update_engine/payload_generator/extent_utils.h"
+
+using chromeos_update_engine::test_utils::ExpectVectorsEq;
+using std::min;
+using std::string;
+using std::vector;
+
+namespace chromeos_update_engine {
+
+namespace {
+const size_t kBlockSize = 8;
+const size_t kRandomIterations = 1000;
+}  // namespace
+
+class ExtentReaderTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    sample_.resize(4096 * 10);
+    srand(time(nullptr));
+    unsigned int rand_seed;
+    for (size_t i = 0; i < sample_.size(); i++) {
+      sample_[i] = rand_r(&rand_seed) % 256;
+    }
+    ASSERT_TRUE(utils::WriteFile(
+        temp_file_.path().c_str(), sample_.data(), sample_.size()));
+
+    fd_.reset(new EintrSafeFileDescriptor());
+    ASSERT_TRUE(fd_->Open(temp_file_.path().c_str(), O_RDONLY, 0600));
+  }
+  void TearDown() override { fd_->Close(); }
+
+  void ReadExtents(vector<Extent> extents, brillo::Blob* blob) {
+    blob->clear();
+    for (const auto& extent : extents) {
+      blob->insert(
+          blob->end(),
+          &sample_[extent.start_block() * kBlockSize],
+          &sample_[(extent.start_block() + extent.num_blocks()) * kBlockSize]);
+    }
+  }
+
+  FileDescriptorPtr fd_;
+  test_utils::ScopedTempFile temp_file_{"ExtentReaderTest-file.XXXXXX"};
+  brillo::Blob sample_;
+};
+
+TEST_F(ExtentReaderTest, SimpleTest) {
+  vector<Extent> extents = {ExtentForRange(1, 1)};
+  DirectExtentReader reader;
+  EXPECT_TRUE(reader.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
+  EXPECT_TRUE(reader.Seek(0));
+  brillo::Blob blob1(utils::BlocksInExtents(extents) * kBlockSize);
+  EXPECT_TRUE(reader.Read(blob1.data(), blob1.size()));
+  brillo::Blob blob2;
+  ReadExtents(extents, &blob2);
+  ExpectVectorsEq(blob1, blob2);
+}
+
+TEST_F(ExtentReaderTest, ZeroExtentLengthTest) {
+  vector<Extent> extents = {ExtentForRange(1, 0)};
+  DirectExtentReader reader;
+  EXPECT_TRUE(reader.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
+  EXPECT_TRUE(reader.Seek(0));
+  brillo::Blob blob(1);
+  EXPECT_TRUE(reader.Read(blob.data(), 0));
+  EXPECT_FALSE(reader.Read(blob.data(), 1));
+}
+
+TEST_F(ExtentReaderTest, NoExtentTest) {
+  DirectExtentReader reader;
+  EXPECT_TRUE(reader.Init(fd_, {}, kBlockSize));
+  EXPECT_TRUE(reader.Seek(0));
+  brillo::Blob blob(1);
+  EXPECT_TRUE(reader.Read(blob.data(), 0));
+  EXPECT_FALSE(reader.Read(blob.data(), 1));
+}
+
+TEST_F(ExtentReaderTest, OverflowExtentTest) {
+  vector<Extent> extents = {ExtentForRange(1, 1)};
+  DirectExtentReader reader;
+  EXPECT_TRUE(reader.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
+  EXPECT_TRUE(reader.Seek(0));
+  brillo::Blob blob(utils::BlocksInExtents(extents) * kBlockSize + 1);
+  EXPECT_FALSE(reader.Read(blob.data(), blob.size()));
+}
+
+TEST_F(ExtentReaderTest, SeekOverflow1Test) {
+  vector<Extent> extents = {ExtentForRange(1, 0)};
+  DirectExtentReader reader;
+  EXPECT_TRUE(reader.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
+  EXPECT_TRUE(reader.Seek(0));
+  EXPECT_FALSE(reader.Seek(1));
+}
+
+TEST_F(ExtentReaderTest, SeekOverflow2Test) {
+  DirectExtentReader reader;
+  reader.Init(fd_, {}, kBlockSize);
+  EXPECT_TRUE(reader.Seek(0));
+  EXPECT_FALSE(reader.Seek(1));
+}
+
+TEST_F(ExtentReaderTest, SeekOverflow3Test) {
+  vector<Extent> extents = {ExtentForRange(1, 1)};
+  DirectExtentReader reader;
+  EXPECT_TRUE(reader.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
+  // Seek to the end of the extents should be fine as long as nothing is read.
+  EXPECT_TRUE(reader.Seek(kBlockSize));
+  EXPECT_FALSE(reader.Seek(kBlockSize + 1));
+}
+
+TEST_F(ExtentReaderTest, RandomReadTest) {
+  vector<Extent> extents = {ExtentForRange(0, 0),
+                            ExtentForRange(1, 1),
+                            ExtentForRange(3, 0),
+                            ExtentForRange(4, 2),
+                            ExtentForRange(7, 1)};
+  DirectExtentReader reader;
+  EXPECT_TRUE(reader.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
+
+  brillo::Blob result;
+  ReadExtents(extents, &result);
+
+  brillo::Blob blob(utils::BlocksInExtents(extents) * kBlockSize);
+  srand(time(nullptr));
+  uint32_t rand_seed;
+  for (size_t idx = 0; idx < kRandomIterations; idx++) {
+    // zero to full size available.
+    size_t start = rand_r(&rand_seed) % blob.size();
+    size_t size = rand_r(&rand_seed) % (blob.size() - start);
+    EXPECT_TRUE(reader.Seek(start));
+    EXPECT_TRUE(reader.Read(blob.data(), size));
+    for (size_t i = 0; i < size; i++) {
+      ASSERT_EQ(blob[i], result[start + i]);
+    }
+  }
+}
+
+}  // namespace chromeos_update_engine
diff --git a/payload_consumer/extent_writer.cc b/payload_consumer/extent_writer.cc
index 5501e22..c5776ec 100644
--- a/payload_consumer/extent_writer.cc
+++ b/payload_consumer/extent_writer.cc
@@ -34,21 +34,19 @@
     return true;
   const char* c_bytes = reinterpret_cast<const char*>(bytes);
   size_t bytes_written = 0;
-  while (count - bytes_written > 0) {
-    TEST_AND_RETURN_FALSE(next_extent_index_ < extents_.size());
-    uint64_t bytes_remaining_next_extent =
-        extents_[next_extent_index_].num_blocks() * block_size_ -
-        extent_bytes_written_;
-    CHECK_NE(bytes_remaining_next_extent, static_cast<uint64_t>(0));
+  while (bytes_written < count) {
+    TEST_AND_RETURN_FALSE(cur_extent_ != extents_.end());
+    uint64_t bytes_remaining_cur_extent =
+        cur_extent_->num_blocks() * block_size_ - extent_bytes_written_;
+    CHECK_NE(bytes_remaining_cur_extent, static_cast<uint64_t>(0));
     size_t bytes_to_write =
         static_cast<size_t>(min(static_cast<uint64_t>(count - bytes_written),
-                                bytes_remaining_next_extent));
+                                bytes_remaining_cur_extent));
     TEST_AND_RETURN_FALSE(bytes_to_write > 0);
 
-    if (extents_[next_extent_index_].start_block() != kSparseHole) {
+    if (cur_extent_->start_block() != kSparseHole) {
       const off64_t offset =
-          extents_[next_extent_index_].start_block() * block_size_ +
-          extent_bytes_written_;
+          cur_extent_->start_block() * block_size_ + extent_bytes_written_;
       TEST_AND_RETURN_FALSE_ERRNO(fd_->Seek(offset, SEEK_SET) !=
                                   static_cast<off64_t>(-1));
       TEST_AND_RETURN_FALSE(
@@ -56,13 +54,12 @@
     }
     bytes_written += bytes_to_write;
     extent_bytes_written_ += bytes_to_write;
-    if (bytes_remaining_next_extent == bytes_to_write) {
+    if (bytes_remaining_cur_extent == bytes_to_write) {
       // We filled this extent
-      CHECK_EQ(extent_bytes_written_,
-               extents_[next_extent_index_].num_blocks() * block_size_);
+      CHECK_EQ(extent_bytes_written_, cur_extent_->num_blocks() * block_size_);
       // move to next extent
       extent_bytes_written_ = 0;
-      next_extent_index_++;
+      cur_extent_++;
     }
   }
   return true;
diff --git a/payload_consumer/extent_writer.h b/payload_consumer/extent_writer.h
index 6484ebf..2c15861 100644
--- a/payload_consumer/extent_writer.h
+++ b/payload_consumer/extent_writer.h
@@ -17,7 +17,8 @@
 #ifndef UPDATE_ENGINE_PAYLOAD_CONSUMER_EXTENT_WRITER_H_
 #define UPDATE_ENGINE_PAYLOAD_CONSUMER_EXTENT_WRITER_H_
 
-#include <vector>
+#include <memory>
+#include <utility>
 
 #include <base/logging.h>
 #include <brillo/secure_blob.h>
@@ -40,7 +41,7 @@
 
   // Returns true on success.
   virtual bool Init(FileDescriptorPtr fd,
-                    const std::vector<Extent>& extents,
+                    const google::protobuf::RepeatedPtrField<Extent>& extents,
                     uint32_t block_size) = 0;
 
   // Returns true on success.
@@ -66,11 +67,12 @@
   ~DirectExtentWriter() override = default;
 
   bool Init(FileDescriptorPtr fd,
-            const std::vector<Extent>& extents,
+            const google::protobuf::RepeatedPtrField<Extent>& extents,
             uint32_t block_size) override {
     fd_ = fd;
     block_size_ = block_size;
     extents_ = extents;
+    cur_extent_ = extents_.begin();
     return true;
   }
   bool Write(const void* bytes, size_t count) override;
@@ -80,11 +82,11 @@
   FileDescriptorPtr fd_{nullptr};
 
   size_t block_size_{0};
-  // Bytes written into next_extent_index_ thus far
+  // Bytes written into |cur_extent_| thus far.
   uint64_t extent_bytes_written_{0};
-  std::vector<Extent> extents_;
-  // The next call to write should correspond to extents_[next_extent_index_]
-  std::vector<Extent>::size_type next_extent_index_{0};
+  google::protobuf::RepeatedPtrField<Extent> extents_;
+  // The next call to write should correspond to |cur_extents_|.
+  google::protobuf::RepeatedPtrField<Extent>::iterator cur_extent_;
 };
 
 // Takes an underlying ExtentWriter to which all operations are delegated.
@@ -100,7 +102,7 @@
   ~ZeroPadExtentWriter() override = default;
 
   bool Init(FileDescriptorPtr fd,
-            const std::vector<Extent>& extents,
+            const google::protobuf::RepeatedPtrField<Extent>& extents,
             uint32_t block_size) override {
     block_size_ = block_size;
     return underlying_extent_writer_->Init(fd, extents, block_size);
diff --git a/payload_consumer/extent_writer_unittest.cc b/payload_consumer/extent_writer_unittest.cc
index 24d238e..48b27cb 100644
--- a/payload_consumer/extent_writer_unittest.cc
+++ b/payload_consumer/extent_writer_unittest.cc
@@ -19,16 +19,17 @@
 #include <fcntl.h>
 
 #include <algorithm>
+#include <memory>
 #include <string>
 #include <vector>
 
-#include <brillo/make_unique_ptr.h>
 #include <brillo/secure_blob.h>
 #include <gtest/gtest.h>
 
 #include "update_engine/common/test_utils.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/payload_consumer/payload_constants.h"
+#include "update_engine/payload_generator/extent_ranges.h"
 
 using chromeos_update_engine::test_utils::ExpectVectorsEq;
 using std::min;
@@ -65,16 +66,11 @@
 };
 
 TEST_F(ExtentWriterTest, SimpleTest) {
-  vector<Extent> extents;
-  Extent extent;
-  extent.set_start_block(1);
-  extent.set_num_blocks(1);
-  extents.push_back(extent);
-
+  vector<Extent> extents = {ExtentForRange(1, 1)};
   const string bytes = "1234";
-
   DirectExtentWriter direct_writer;
-  EXPECT_TRUE(direct_writer.Init(fd_, extents, kBlockSize));
+  EXPECT_TRUE(
+      direct_writer.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
   EXPECT_TRUE(direct_writer.Write(bytes.data(), bytes.size()));
   EXPECT_TRUE(direct_writer.End());
 
@@ -91,14 +87,10 @@
 }
 
 TEST_F(ExtentWriterTest, ZeroLengthTest) {
-  vector<Extent> extents;
-  Extent extent;
-  extent.set_start_block(1);
-  extent.set_num_blocks(1);
-  extents.push_back(extent);
-
+  vector<Extent> extents = {ExtentForRange(1, 1)};
   DirectExtentWriter direct_writer;
-  EXPECT_TRUE(direct_writer.Init(fd_, extents, kBlockSize));
+  EXPECT_TRUE(
+      direct_writer.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
   EXPECT_TRUE(direct_writer.Write(nullptr, 0));
   EXPECT_TRUE(direct_writer.End());
 }
@@ -117,23 +109,14 @@
 
 void ExtentWriterTest::WriteAlignedExtents(size_t chunk_size,
                                            size_t first_chunk_size) {
-  vector<Extent> extents;
-  Extent extent;
-  extent.set_start_block(1);
-  extent.set_num_blocks(1);
-  extents.push_back(extent);
-  extent.set_start_block(0);
-  extent.set_num_blocks(1);
-  extents.push_back(extent);
-  extent.set_start_block(2);
-  extent.set_num_blocks(1);
-  extents.push_back(extent);
-
+  vector<Extent> extents = {
+      ExtentForRange(1, 1), ExtentForRange(0, 1), ExtentForRange(2, 1)};
   brillo::Blob data(kBlockSize * 3);
   test_utils::FillWithData(&data);
 
   DirectExtentWriter direct_writer;
-  EXPECT_TRUE(direct_writer.Init(fd_, extents, kBlockSize));
+  EXPECT_TRUE(
+      direct_writer.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
 
   size_t bytes_written = 0;
   while (bytes_written < data.size()) {
@@ -172,22 +155,14 @@
 }
 
 void ExtentWriterTest::TestZeroPad(bool aligned_size) {
-  vector<Extent> extents;
-  Extent extent;
-  extent.set_start_block(1);
-  extent.set_num_blocks(1);
-  extents.push_back(extent);
-  extent.set_start_block(0);
-  extent.set_num_blocks(1);
-  extents.push_back(extent);
-
+  vector<Extent> extents = {ExtentForRange(1, 1), ExtentForRange(0, 1)};
   brillo::Blob data(kBlockSize * 2);
   test_utils::FillWithData(&data);
 
-  ZeroPadExtentWriter zero_pad_writer(
-      brillo::make_unique_ptr(new DirectExtentWriter()));
+  ZeroPadExtentWriter zero_pad_writer(std::make_unique<DirectExtentWriter>());
 
-  EXPECT_TRUE(zero_pad_writer.Init(fd_, extents, kBlockSize));
+  EXPECT_TRUE(
+      zero_pad_writer.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
   size_t bytes_to_write = data.size();
   const size_t missing_bytes = (aligned_size ? 0 : 9);
   bytes_to_write -= missing_bytes;
@@ -216,17 +191,9 @@
 }
 
 TEST_F(ExtentWriterTest, SparseFileTest) {
-  vector<Extent> extents;
-  Extent extent;
-  extent.set_start_block(1);
-  extent.set_num_blocks(1);
-  extents.push_back(extent);
-  extent.set_start_block(kSparseHole);
-  extent.set_num_blocks(2);
-  extents.push_back(extent);
-  extent.set_start_block(0);
-  extent.set_num_blocks(1);
-  extents.push_back(extent);
+  vector<Extent> extents = {ExtentForRange(1, 1),
+                            ExtentForRange(kSparseHole, 2),
+                            ExtentForRange(0, 1)};
   const int block_count = 4;
   const int on_disk_count = 2;
 
@@ -234,7 +201,8 @@
   test_utils::FillWithData(&data);
 
   DirectExtentWriter direct_writer;
-  EXPECT_TRUE(direct_writer.Init(fd_, extents, kBlockSize));
+  EXPECT_TRUE(
+      direct_writer.Init(fd_, {extents.begin(), extents.end()}, kBlockSize));
 
   size_t bytes_written = 0;
   while (bytes_written < (block_count * kBlockSize)) {
diff --git a/payload_consumer/fake_extent_writer.h b/payload_consumer/fake_extent_writer.h
index 762c6d5..4418a9e 100644
--- a/payload_consumer/fake_extent_writer.h
+++ b/payload_consumer/fake_extent_writer.h
@@ -18,7 +18,6 @@
 #define UPDATE_ENGINE_PAYLOAD_CONSUMER_FAKE_EXTENT_WRITER_H_
 
 #include <memory>
-#include <vector>
 
 #include <brillo/secure_blob.h>
 
@@ -35,7 +34,7 @@
 
   // ExtentWriter overrides.
   bool Init(FileDescriptorPtr /* fd */,
-            const std::vector<Extent>& /* extents */,
+            const google::protobuf::RepeatedPtrField<Extent>& /* extents */,
             uint32_t /* block_size */) override {
     init_called_ = true;
     return true;
diff --git a/payload_consumer/fake_file_descriptor.cc b/payload_consumer/fake_file_descriptor.cc
new file mode 100644
index 0000000..d54856b
--- /dev/null
+++ b/payload_consumer/fake_file_descriptor.cc
@@ -0,0 +1,76 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/payload_consumer/fake_file_descriptor.h"
+
+namespace chromeos_update_engine {
+
+ssize_t FakeFileDescriptor::Read(void* buf, size_t count) {
+  // Record the read operation so it can later be inspected.
+  read_ops_.emplace_back(offset_, count);
+
+  // Check for the EOF condition first to avoid reporting it as a failure.
+  if (offset_ >= static_cast<uint64_t>(size_) || count == 0)
+    return 0;
+  // Find the first offset greater or equal than the current position where a
+  // failure will occur. This will mark the end of the read chunk.
+  uint64_t first_failure = size_;
+  for (const auto& failure : failure_ranges_) {
+    // A failure range that includes the current offset results in an
+    // immediate failure to read any bytes.
+    if (failure.first <= offset_ && offset_ < failure.first + failure.second) {
+      errno = EIO;
+      return -1;
+    }
+    if (failure.first > offset_)
+      first_failure = std::min(first_failure, failure.first);
+  }
+  count = std::min(static_cast<uint64_t>(count), first_failure - offset_);
+  static const char kHexChars[] = "0123456789ABCDEF";
+  for (size_t i = 0; i < count; ++i) {
+    // Encode the 16-bit number "offset_ / 4" as a hex digit in big-endian.
+    uint16_t current_num = offset_ / 4;
+    uint8_t current_digit = (current_num >> (4 * (3 - offset_ % 4))) & 0x0f;
+
+    static_cast<uint8_t*>(buf)[i] = kHexChars[current_digit];
+    offset_++;
+  }
+
+  return count;
+}
+
+off64_t FakeFileDescriptor::Seek(off64_t offset, int whence) {
+  switch (whence) {
+    case SEEK_SET:
+      offset_ = offset;
+      break;
+    case SEEK_CUR:
+      offset_ += offset;
+      break;
+    case SEEK_END:
+      if (offset > size_)
+        offset_ = 0;
+      else
+        offset_ = size_ - offset_;
+      break;
+    default:
+      errno = EINVAL;
+      return -1;
+  }
+  return offset_;
+}
+
+}  // namespace chromeos_update_engine
diff --git a/payload_consumer/fake_file_descriptor.h b/payload_consumer/fake_file_descriptor.h
new file mode 100644
index 0000000..f17820b
--- /dev/null
+++ b/payload_consumer/fake_file_descriptor.h
@@ -0,0 +1,126 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_PAYLOAD_CONSUMER_FAKE_FILE_DESCRIPTOR_H_
+#define UPDATE_ENGINE_PAYLOAD_CONSUMER_FAKE_FILE_DESCRIPTOR_H_
+
+#include <algorithm>
+#include <limits>
+#include <utility>
+#include <vector>
+
+#include "update_engine/payload_consumer/file_descriptor.h"
+
+namespace chromeos_update_engine {
+
+// A fake file descriptor with configurable errors. The file descriptor always
+// reads a fixed sequence of bytes, consisting of the concatenation of the
+// numbers 0, 1, 2... each one encoded in 4 bytes as the big-endian 16-bit
+// number encoded in hexadecimal. For example, the beginning of the stream in
+// ASCII is 0000000100020003... which corresponds to the numbers 0, 1, 2 and 3.
+class FakeFileDescriptor : public FileDescriptor {
+ public:
+  FakeFileDescriptor() = default;
+  ~FakeFileDescriptor() override = default;
+
+  // FileDescriptor override methods.
+  bool Open(const char* path, int flags, mode_t mode) override {
+    if (open_)
+      return false;
+    open_ = true;
+    return true;
+  }
+
+  bool Open(const char* path, int flags) override {
+    return Open(path, flags, 0);
+  }
+
+  ssize_t Read(void* buf, size_t count) override;
+
+  ssize_t Write(const void* buf, size_t count) override {
+    // Read-only block device.
+    errno = EROFS;
+    return -1;
+  }
+
+  off64_t Seek(off64_t offset, int whence) override;
+
+  uint64_t BlockDevSize() override { return size_; }
+
+  bool BlkIoctl(int request,
+                uint64_t start,
+                uint64_t length,
+                int* result) override {
+    return false;
+  }
+
+  bool Flush() override {
+    return open_;
+  }
+
+  bool Close() override {
+    if (!open_)
+      return false;
+    open_ = false;
+    return true;
+  }
+
+  bool IsSettingErrno() override { return true; }
+
+  bool IsOpen() override { return open_; }
+
+  // Fake class configuration methods.
+
+  // Set the size of the file.
+  void SetFileSize(uint64_t size) { size_ = size; }
+
+  // Marks the range starting from |offset| bytes into the file and |length|
+  // size as a failure range. Reads from this range will always fail.
+  void AddFailureRange(uint64_t offset, uint64_t length) {
+    if (length == 0)
+      return;
+    failure_ranges_.emplace_back(offset, length);
+  }
+
+  // Return the list of ranges of bytes requested with a Read() as (offset,
+  // length), regardless of the Read() return value.
+  std::vector<std::pair<uint64_t, uint64_t>> GetReadOps() const {
+    return read_ops_;
+  }
+
+ private:
+  // Whether the fake file is open.
+  bool open_{false};
+
+  // The current file pointer offset into the fake file.
+  uint64_t offset_{0};
+
+  // The size of the file. Reads beyond |max_size_| will an EOF condition.
+  off64_t size_{std::numeric_limits<off64_t>::max()};
+
+  // The list of ranges represented as (start, length) in bytes where reads will
+  // always fail.
+  std::vector<std::pair<uint64_t, uint64_t>> failure_ranges_;
+
+  // List of reads performed as (offset, length) of the read request.
+  std::vector<std::pair<uint64_t, uint64_t>> read_ops_;
+
+  DISALLOW_COPY_AND_ASSIGN(FakeFileDescriptor);
+};
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_PAYLOAD_CONSUMER_FAKE_FILE_DESCRIPTOR_H_
diff --git a/payload_consumer/file_descriptor.cc b/payload_consumer/file_descriptor.cc
index 8a23dea..4eabb8f 100644
--- a/payload_consumer/file_descriptor.cc
+++ b/payload_consumer/file_descriptor.cc
@@ -123,16 +123,17 @@
 #endif  // defined(BLKZEROOUT)
 }
 
+bool EintrSafeFileDescriptor::Flush() {
+  CHECK_GE(fd_, 0);
+  return true;
+}
+
 bool EintrSafeFileDescriptor::Close() {
   CHECK_GE(fd_, 0);
   if (IGNORE_EINTR(close(fd_)))
     return false;
-  Reset();
-  return true;
-}
-
-void EintrSafeFileDescriptor::Reset() {
   fd_ = -1;
+  return true;
 }
 
 }  // namespace chromeos_update_engine
diff --git a/payload_consumer/file_descriptor.h b/payload_consumer/file_descriptor.h
index 7bb2974..5e524d9 100644
--- a/payload_consumer/file_descriptor.h
+++ b/payload_consumer/file_descriptor.h
@@ -39,12 +39,6 @@
 // * Write() returns the number of bytes written: this appears to be more useful
 //   for clients, who may wish to retry or otherwise do something useful with
 //   the remaining data that was not written.
-//
-// * Provides a Reset() method, which will force to abandon a currently open
-//   file descriptor and allow opening another file, without necessarily
-//   properly closing the old one. This may be useful in cases where a "closer"
-//   class does not care whether Close() was successful, but may need to reuse
-//   the same file descriptor again.
 
 namespace chromeos_update_engine {
 
@@ -93,15 +87,16 @@
                         uint64_t length,
                         int* result) = 0;
 
+  // Flushes any cached data. The descriptor must be opened prior to this
+  // call. Returns false if it fails to write data. Implementations may set
+  // errno accrodingly.
+  virtual bool Flush() = 0;
+
   // Closes a file descriptor. The descriptor must be open prior to this call.
   // Returns true on success, false otherwise. Specific implementations may set
   // errno accordingly.
   virtual bool Close() = 0;
 
-  // Resets the file descriptor, abandoning a currently open file and returning
-  // the descriptor to the closed state.
-  virtual void Reset() = 0;
-
   // Indicates whether or not an implementation sets meaningful errno.
   virtual bool IsSettingErrno() = 0;
 
@@ -128,8 +123,8 @@
                 uint64_t start,
                 uint64_t length,
                 int* result) override;
+  bool Flush() override;
   bool Close() override;
-  void Reset() override;
   bool IsSettingErrno() override {
     return true;
   }
diff --git a/payload_consumer/file_descriptor_utils.cc b/payload_consumer/file_descriptor_utils.cc
new file mode 100644
index 0000000..73f86df
--- /dev/null
+++ b/payload_consumer/file_descriptor_utils.cc
@@ -0,0 +1,85 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/payload_consumer/file_descriptor_utils.h"
+
+#include <algorithm>
+
+#include <base/logging.h>
+
+#include "update_engine/common/hash_calculator.h"
+#include "update_engine/common/utils.h"
+#include "update_engine/payload_consumer/extent_reader.h"
+#include "update_engine/payload_consumer/extent_writer.h"
+
+using google::protobuf::RepeatedPtrField;
+using std::min;
+
+namespace chromeos_update_engine {
+
+namespace {
+
+// Size of the buffer used to copy blocks.
+const int kMaxCopyBufferSize = 1024 * 1024;
+
+}  // namespace
+
+namespace fd_utils {
+
+bool CopyAndHashExtents(FileDescriptorPtr source,
+                        const RepeatedPtrField<Extent>& src_extents,
+                        FileDescriptorPtr target,
+                        const RepeatedPtrField<Extent>& tgt_extents,
+                        uint32_t block_size,
+                        brillo::Blob* hash_out) {
+  uint64_t total_blocks = utils::BlocksInExtents(src_extents);
+  TEST_AND_RETURN_FALSE(total_blocks == utils::BlocksInExtents(tgt_extents));
+
+  DirectExtentReader reader;
+  TEST_AND_RETURN_FALSE(reader.Init(source, src_extents, block_size));
+  DirectExtentWriter writer;
+  TEST_AND_RETURN_FALSE(writer.Init(target, tgt_extents, block_size));
+
+  uint64_t buffer_blocks = kMaxCopyBufferSize / block_size;
+  // Ensure we copy at least one block at a time.
+  if (buffer_blocks < 1)
+    buffer_blocks = 1;
+  brillo::Blob buf(buffer_blocks * block_size);
+
+  HashCalculator source_hasher;
+  uint64_t blocks_left = total_blocks;
+  while (blocks_left > 0) {
+    uint64_t read_blocks = std::min(blocks_left, buffer_blocks);
+    TEST_AND_RETURN_FALSE(reader.Read(buf.data(), read_blocks * block_size));
+    if (hash_out) {
+      TEST_AND_RETURN_FALSE(
+          source_hasher.Update(buf.data(), read_blocks * block_size));
+    }
+    TEST_AND_RETURN_FALSE(writer.Write(buf.data(), read_blocks * block_size));
+    blocks_left -= read_blocks;
+  }
+  TEST_AND_RETURN_FALSE(writer.End());
+
+  if (hash_out) {
+    TEST_AND_RETURN_FALSE(source_hasher.Finalize());
+    *hash_out = source_hasher.raw_hash();
+  }
+  return true;
+}
+
+}  // namespace fd_utils
+
+}  // namespace chromeos_update_engine
diff --git a/payload_consumer/file_descriptor_utils.h b/payload_consumer/file_descriptor_utils.h
new file mode 100644
index 0000000..d1289d6
--- /dev/null
+++ b/payload_consumer/file_descriptor_utils.h
@@ -0,0 +1,48 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_PAYLOAD_CONSUMER_FILE_DESCRIPTOR_UTILS_H_
+#define UPDATE_ENGINE_PAYLOAD_CONSUMER_FILE_DESCRIPTOR_UTILS_H_
+
+#include <brillo/secure_blob.h>
+
+#include "update_engine/payload_consumer/file_descriptor.h"
+#include "update_engine/update_metadata.pb.h"
+
+namespace chromeos_update_engine {
+namespace fd_utils {
+
+// Copy blocks from the |source| file to the |target| file and hashes the
+// contents. The blocks to copy from the |source| to the |target| files are
+// specified by the |src_extents| and |tgt_extents| list of Extents, which
+// must have the same length in number of blocks. Stores the hash of the
+// copied blocks in Blob pointed by |hash_out| if not null. The block size
+// is passed as |block_size|. In case of error reading or writing, returns
+// false and the value pointed by |hash_out| is undefined.
+// The |source| and |target| files must be different, or otherwise |src_extents|
+// and |tgt_extents| must not overlap.
+bool CopyAndHashExtents(
+    FileDescriptorPtr source,
+    const google::protobuf::RepeatedPtrField<Extent>& src_extents,
+    FileDescriptorPtr target,
+    const google::protobuf::RepeatedPtrField<Extent>& tgt_extents,
+    uint32_t block_size,
+    brillo::Blob* hash_out);
+
+}  // namespace fd_utils
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_PAYLOAD_CONSUMER_FILE_DESCRIPTOR_UTILS_H_
diff --git a/payload_consumer/file_descriptor_utils_unittest.cc b/payload_consumer/file_descriptor_utils_unittest.cc
new file mode 100644
index 0000000..8ba8ce6
--- /dev/null
+++ b/payload_consumer/file_descriptor_utils_unittest.cc
@@ -0,0 +1,170 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/payload_consumer/file_descriptor_utils.h"
+
+#include <fcntl.h>
+
+#include <string>
+#include <utility>
+#include <vector>
+
+#include <brillo/data_encoding.h>
+#include <gtest/gtest.h>
+
+#include "update_engine/common/hash_calculator.h"
+#include "update_engine/common/test_utils.h"
+#include "update_engine/common/utils.h"
+#include "update_engine/payload_consumer/fake_file_descriptor.h"
+#include "update_engine/payload_consumer/file_descriptor.h"
+#include "update_engine/payload_generator/extent_ranges.h"
+
+using google::protobuf::RepeatedPtrField;
+
+namespace chromeos_update_engine {
+
+namespace {
+
+RepeatedPtrField<Extent> CreateExtentList(
+    const std::vector<std::pair<uint64_t, uint64_t>>& lst) {
+  RepeatedPtrField<Extent> result;
+  for (const auto& item : lst) {
+    *result.Add() = ExtentForRange(item.first, item.second);
+  }
+  return result;
+}
+
+}  // namespace
+
+class FileDescriptorUtilsTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    EXPECT_TRUE(utils::MakeTempFile("fd_tgt.XXXXXX", &tgt_path_, nullptr));
+    EXPECT_TRUE(target_->Open(tgt_path_.c_str(), O_RDWR));
+  }
+
+  // Check that the |target_| file contains |expected_contents|.
+  void ExpectTarget(const std::string& expected_contents) {
+    std::string target_contents;
+    EXPECT_TRUE(utils::ReadFile(tgt_path_, &target_contents));
+    EXPECT_EQ(expected_contents.size(), target_contents.size());
+    if (target_contents != expected_contents) {
+      ADD_FAILURE() << "Contents don't match.";
+      LOG(INFO) << "Expected contents:";
+      utils::HexDumpString(expected_contents);
+      LOG(INFO) << "Actual contents:";
+      utils::HexDumpString(target_contents);
+    }
+  }
+
+  // Path to the target temporary file.
+  std::string tgt_path_;
+
+  // Source and target file descriptor used for testing the tools.
+  FakeFileDescriptor* fake_source_{new FakeFileDescriptor()};
+  FileDescriptorPtr source_{fake_source_};
+  FileDescriptorPtr target_{new EintrSafeFileDescriptor()};
+};
+
+// Source and target extents should have the same number of blocks.
+TEST_F(FileDescriptorUtilsTest, CopyAndHashExtentsMismatchBlocksTest) {
+  auto src_extents = CreateExtentList({{1, 4}});
+  auto tgt_extents = CreateExtentList({{0, 5}});
+
+  EXPECT_FALSE(fd_utils::CopyAndHashExtents(
+      source_, src_extents, target_, tgt_extents, 4, nullptr));
+}
+
+// Failing to read from the source should fail the copy.
+TEST_F(FileDescriptorUtilsTest, CopyAndHashExtentsReadFailureTest) {
+  auto extents = CreateExtentList({{0, 5}});
+  fake_source_->AddFailureRange(10, 5);
+
+  EXPECT_FALSE(fd_utils::CopyAndHashExtents(
+      source_, extents, target_, extents, 4, nullptr));
+}
+
+// Failing to write to the target should fail the copy.
+TEST_F(FileDescriptorUtilsTest, CopyAndHashExtentsWriteFailureTest) {
+  auto src_extents = CreateExtentList({{0, 2}});
+  auto tgt_extents = CreateExtentList({{5, 2}});
+  fake_source_->AddFailureRange(5 * 4, 10);
+
+  // Note that we pass |source_| as the target as well, which should fail to
+  // write.
+  EXPECT_FALSE(fd_utils::CopyAndHashExtents(
+      source_, src_extents, source_, tgt_extents, 4, nullptr));
+}
+
+// Test that we can copy extents without hashing them, allowing a nullptr
+// pointer as hash_out.
+TEST_F(FileDescriptorUtilsTest, CopyAndHashExtentsWithoutHashingTest) {
+  auto extents = CreateExtentList({{0, 5}});
+
+  EXPECT_TRUE(fd_utils::CopyAndHashExtents(
+      source_, extents, target_, extents, 4, nullptr));
+  ExpectTarget("00000001000200030004");
+}
+
+// CopyAndHash() can take different number of extents in the source and target
+// files, as long as the number of blocks is the same. Test that it handles it
+// properly.
+TEST_F(FileDescriptorUtilsTest, CopyAndHashExtentsManyToOneTest) {
+  brillo::Blob hash_out;
+  // Reorder the input as 1 4 2 3 0.
+  auto src_extents = CreateExtentList({{1, 1}, {4, 1}, {2, 2}, {0, 1}});
+  auto tgt_extents = CreateExtentList({{0, 5}});
+
+  EXPECT_TRUE(fd_utils::CopyAndHashExtents(
+      source_, src_extents, target_, tgt_extents, 4, &hash_out));
+  const char kExpectedResult[] = "00010004000200030000";
+  ExpectTarget(kExpectedResult);
+
+  brillo::Blob expected_hash;
+  EXPECT_TRUE(HashCalculator::RawHashOfBytes(
+      kExpectedResult, strlen(kExpectedResult), &expected_hash));
+  EXPECT_EQ(expected_hash, hash_out);
+}
+
+TEST_F(FileDescriptorUtilsTest, CopyAndHashExtentsManyToManyTest) {
+  brillo::Blob hash_out;
+  auto src_extents = CreateExtentList({{1, 1}, {4, 1}, {2, 2}, {0, 1}});
+  auto tgt_extents = CreateExtentList({{2, 3}, {0, 2}});
+
+  EXPECT_TRUE(fd_utils::CopyAndHashExtents(
+      source_, src_extents, target_, tgt_extents, 4, &hash_out));
+  // The reads always match the source extent list of blocks (up to the
+  // internal buffer size).
+  std::vector<std::pair<uint64_t, uint64_t>> kExpectedOps = {
+      {4, 4}, {16, 4}, {8, 8}, {0, 4}};
+  EXPECT_EQ(kExpectedOps, fake_source_->GetReadOps());
+
+  // The output here is as in the previous test but the first 3 4-byte blocks
+  // are at the end of the stream. The expected hash is as in the previous
+  // example anyway since the hash doesn't depend on the order of the target
+  // blocks.
+  const char kExpectedResult[] = "00030000000100040002";
+  ExpectTarget(kExpectedResult);
+
+  // The data in the order that the reader processes (and hashes) it.
+  const char kExpectedOrderedData[] = "00010004000200030000";
+  brillo::Blob expected_hash;
+  EXPECT_TRUE(HashCalculator::RawHashOfBytes(
+      kExpectedOrderedData, strlen(kExpectedOrderedData), &expected_hash));
+  EXPECT_EQ(expected_hash, hash_out);
+}
+
+}  // namespace chromeos_update_engine
diff --git a/payload_consumer/file_writer_unittest.cc b/payload_consumer/file_writer_unittest.cc
index debb4c3..92837c8 100644
--- a/payload_consumer/file_writer_unittest.cc
+++ b/payload_consumer/file_writer_unittest.cc
@@ -21,7 +21,6 @@
 #include <unistd.h>
 
 #include <string>
-#include <vector>
 
 #include <brillo/secure_blob.h>
 #include <gtest/gtest.h>
@@ -30,7 +29,6 @@
 #include "update_engine/common/utils.h"
 
 using std::string;
-using std::vector;
 
 namespace chromeos_update_engine {
 
diff --git a/payload_consumer/filesystem_verifier_action_unittest.cc b/payload_consumer/filesystem_verifier_action_unittest.cc
index 2e1d95d..b4f7f7f 100644
--- a/payload_consumer/filesystem_verifier_action_unittest.cc
+++ b/payload_consumer/filesystem_verifier_action_unittest.cc
@@ -26,7 +26,6 @@
 #include <base/posix/eintr_wrapper.h>
 #include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
-#include <brillo/bind_lambda.h>
 #include <brillo/message_loops/fake_message_loop.h>
 #include <brillo/message_loops/message_loop_utils.h>
 #include <gmock/gmock.h>
diff --git a/payload_consumer/install_plan.cc b/payload_consumer/install_plan.cc
index d5d745b..45112d6 100644
--- a/payload_consumer/install_plan.cc
+++ b/payload_consumer/install_plan.cc
@@ -74,13 +74,23 @@
         InstallPayloadTypeToString(payload.type).c_str());
   }
 
+  string version_str = base::StringPrintf(", version: %s", version.c_str());
+  if (!system_version.empty()) {
+    version_str +=
+        base::StringPrintf(", system_version: %s", system_version.c_str());
+  }
+
   LOG(INFO) << "InstallPlan: " << (is_resume ? "resume" : "new_update")
+            << version_str
             << ", source_slot: " << BootControlInterface::SlotName(source_slot)
             << ", target_slot: " << BootControlInterface::SlotName(target_slot)
             << ", url: " << download_url << payloads_str << partitions_str
             << ", hash_checks_mandatory: "
             << utils::ToString(hash_checks_mandatory)
-            << ", powerwash_required: " << utils::ToString(powerwash_required);
+            << ", powerwash_required: " << utils::ToString(powerwash_required)
+            << ", switch_slot_on_reboot: "
+            << utils::ToString(switch_slot_on_reboot)
+            << ", run_post_install: " << utils::ToString(run_post_install);
 }
 
 bool InstallPlan::LoadPartitionsFromSlots(BootControlInterface* boot_control) {
diff --git a/payload_consumer/install_plan.h b/payload_consumer/install_plan.h
index 6dd5a73..5cdfbc1 100644
--- a/payload_consumer/install_plan.h
+++ b/payload_consumer/install_plan.h
@@ -54,6 +54,8 @@
   bool is_resume{false};
   std::string download_url;  // url to download from
   std::string version;       // version we are installing.
+  // system version, if present and separate from version
+  std::string system_version;
 
   struct Payload {
     uint64_t size = 0;               // size of the payload
@@ -117,6 +119,14 @@
   // False otherwise.
   bool powerwash_required{false};
 
+  // True if the updated slot should be marked active on success.
+  // False otherwise.
+  bool switch_slot_on_reboot{true};
+
+  // True if the update should run its post-install step.
+  // False otherwise.
+  bool run_post_install{true};
+
   // If not blank, a base-64 encoded representation of the PEM-encoded
   // public key in the response.
   std::string public_key_rsa;
diff --git a/payload_consumer/mtd_file_descriptor.cc b/payload_consumer/mtd_file_descriptor.cc
index 3f0a33f..5d7758a 100644
--- a/payload_consumer/mtd_file_descriptor.cc
+++ b/payload_consumer/mtd_file_descriptor.cc
@@ -18,11 +18,12 @@
 
 #include <fcntl.h>
 #include <mtd/ubi-user.h>
-#include <string>
 #include <sys/ioctl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-#include <vector>
+
+#include <memory>
+#include <string>
 
 #include <base/files/file_path.h>
 #include <base/strings/string_number_conversions.h>
@@ -33,7 +34,6 @@
 #include "update_engine/common/utils.h"
 
 using std::string;
-using std::vector;
 
 namespace {
 
diff --git a/payload_consumer/payload_constants.cc b/payload_consumer/payload_constants.cc
index de0fd74..ad193a0 100644
--- a/payload_consumer/payload_constants.cc
+++ b/payload_consumer/payload_constants.cc
@@ -25,24 +25,13 @@
 const uint32_t kInPlaceMinorPayloadVersion = 1;
 const uint32_t kSourceMinorPayloadVersion = 2;
 const uint32_t kOpSrcHashMinorPayloadVersion = 3;
-const uint32_t kImgdiffMinorPayloadVersion = 4;
+const uint32_t kPuffdiffMinorPayloadVersion = 4;
 
 const char kLegacyPartitionNameKernel[] = "boot";
 const char kLegacyPartitionNameRoot[] = "system";
 
 const char kDeltaMagic[4] = {'C', 'r', 'A', 'U'};
 
-// The zlib in Android and Chrome OS are currently compatible with each other,
-// so they are sharing the same array, but if in the future they are no longer
-// compatible with each other, we coule make the same change on the other one to
-// make them compatible again or use ifdef here.
-const char kCompatibleZlibFingerprint[][65] = {
-    "ea973605ccbbdb24f59f449c5f65861a1a9bc7a4353377aaaa06cb3e0f1cfbd7",
-    "3747fa404cceb00a5ec3606fc779510aaa784d5864ab1d5c28b9e267c40aad5c",
-    // zlib 1.2.11
-    "61514794a2985bee78135fd67a2f1fd18e56f3c3e410fbc4552a0e05a701e47a",
-};
-
 const char* InstallOperationTypeName(InstallOperation_Type op_type) {
   switch (op_type) {
     case InstallOperation::BSDIFF:
@@ -63,8 +52,10 @@
       return "DISCARD";
     case InstallOperation::REPLACE_XZ:
       return "REPLACE_XZ";
-    case InstallOperation::IMGDIFF:
-      return "IMGDIFF";
+    case InstallOperation::PUFFDIFF:
+      return "PUFFDIFF";
+    case InstallOperation::BROTLI_BSDIFF:
+      return "BROTLI_BSDIFF";
   }
   return "<unknown_op>";
 }
diff --git a/payload_consumer/payload_constants.h b/payload_consumer/payload_constants.h
index 7509ed2..1e2e810 100644
--- a/payload_consumer/payload_constants.h
+++ b/payload_consumer/payload_constants.h
@@ -43,9 +43,8 @@
 // The minor version that allows per-operation source hash.
 extern const uint32_t kOpSrcHashMinorPayloadVersion;
 
-// The minor version that allows IMGDIFF operation.
-extern const uint32_t kImgdiffMinorPayloadVersion;
-
+// The minor version that allows PUFFDIFF operation.
+extern const uint32_t kPuffdiffMinorPayloadVersion;
 
 // The kernel and rootfs partition names used by the BootControlInterface when
 // handling update payloads with a major version 1. The names of the updated
@@ -56,15 +55,6 @@
 extern const char kBspatchPath[];
 extern const char kDeltaMagic[4];
 
-// The list of compatible SHA256 hashes of zlib source code.
-// This is used to check if the source image have a compatible zlib (produce
-// same compressed result given the same input).
-// When a new fingerprint is found, please examine the changes in zlib source
-// carefully and determine if it's still compatible with previous version, if
-// yes then add the new fingerprint to this array, otherwise remove all previous
-// fingerprints in the array first, and only include the new fingerprint.
-extern const char kCompatibleZlibFingerprint[3][65];
-
 // A block number denoting a hole on a sparse file. Used on Extents to refer to
 // section of blocks not present on disk on a sparse file.
 const uint64_t kSparseHole = std::numeric_limits<uint64_t>::max();
diff --git a/payload_consumer/payload_verifier.h b/payload_consumer/payload_verifier.h
index 22ced40..8caef35 100644
--- a/payload_consumer/payload_verifier.h
+++ b/payload_consumer/payload_verifier.h
@@ -18,7 +18,6 @@
 #define UPDATE_ENGINE_PAYLOAD_CONSUMER_PAYLOAD_VERIFIER_H_
 
 #include <string>
-#include <vector>
 
 #include <base/macros.h>
 #include <brillo/secure_blob.h>
diff --git a/payload_consumer/postinstall_runner_action.cc b/payload_consumer/postinstall_runner_action.cc
index 27a9ed6..cedecda 100644
--- a/payload_consumer/postinstall_runner_action.cc
+++ b/payload_consumer/postinstall_runner_action.cc
@@ -82,6 +82,11 @@
 }
 
 void PostinstallRunnerAction::PerformPartitionPostinstall() {
+  if (!install_plan_.run_post_install) {
+    LOG(INFO) << "Skipping post-install according to install plan.";
+    return CompletePostinstall(ErrorCode::kSuccess);
+  }
+
   if (install_plan_.download_url.empty()) {
     LOG(INFO) << "Skipping post-install during rollback";
     return CompletePostinstall(ErrorCode::kSuccess);
@@ -331,15 +336,21 @@
 void PostinstallRunnerAction::CompletePostinstall(ErrorCode error_code) {
   // We only attempt to mark the new slot as active if all the postinstall
   // steps succeeded.
-  if (error_code == ErrorCode::kSuccess &&
-      !boot_control_->SetActiveBootSlot(install_plan_.target_slot)) {
-    error_code = ErrorCode::kPostinstallRunnerError;
+  if (error_code == ErrorCode::kSuccess) {
+    if (install_plan_.switch_slot_on_reboot) {
+      if (!boot_control_->SetActiveBootSlot(install_plan_.target_slot)) {
+        error_code = ErrorCode::kPostinstallRunnerError;
+      }
+    } else {
+      error_code = ErrorCode::kUpdatedButNotActive;
+    }
   }
 
   ScopedActionCompleter completer(processor_, this);
   completer.set_code(error_code);
 
-  if (error_code != ErrorCode::kSuccess) {
+  if (error_code != ErrorCode::kSuccess &&
+      error_code != ErrorCode::kUpdatedButNotActive) {
     LOG(ERROR) << "Postinstall action failed.";
 
     // Undo any changes done to trigger Powerwash.
diff --git a/payload_consumer/postinstall_runner_action_unittest.cc b/payload_consumer/postinstall_runner_action_unittest.cc
index e82a866..f15171b 100644
--- a/payload_consumer/postinstall_runner_action_unittest.cc
+++ b/payload_consumer/postinstall_runner_action_unittest.cc
@@ -22,14 +22,12 @@
 
 #include <memory>
 #include <string>
-#include <vector>
 
 #include <base/bind.h>
 #include <base/files/file_util.h>
 #include <base/message_loop/message_loop.h>
 #include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
-#include <brillo/bind_lambda.h>
 #include <brillo/message_loops/base_message_loop.h>
 #include <brillo/message_loops/message_loop_utils.h>
 #include <gmock/gmock.h>
@@ -44,7 +42,6 @@
 using brillo::MessageLoop;
 using chromeos_update_engine::test_utils::ScopedLoopbackDeviceBinder;
 using std::string;
-using std::vector;
 
 namespace chromeos_update_engine {
 
diff --git a/payload_consumer/xz_extent_writer.cc b/payload_consumer/xz_extent_writer.cc
index 4bd893d..343ed80 100644
--- a/payload_consumer/xz_extent_writer.cc
+++ b/payload_consumer/xz_extent_writer.cc
@@ -16,7 +16,7 @@
 
 #include "update_engine/payload_consumer/xz_extent_writer.h"
 
-using std::vector;
+using google::protobuf::RepeatedPtrField;
 
 namespace chromeos_update_engine {
 
@@ -47,7 +47,7 @@
       return "<unknown xz error>";
   }
   #undef __XZ_ERROR_STRING_CASE
-};
+}
 }  // namespace
 
 XzExtentWriter::~XzExtentWriter() {
@@ -55,7 +55,7 @@
 }
 
 bool XzExtentWriter::Init(FileDescriptorPtr fd,
-                          const vector<Extent>& extents,
+                          const RepeatedPtrField<Extent>& extents,
                           uint32_t block_size) {
   stream_ = xz_dec_init(XZ_DYNALLOC, kXzMaxDictSize);
   TEST_AND_RETURN_FALSE(stream_ != nullptr);
diff --git a/payload_consumer/xz_extent_writer.h b/payload_consumer/xz_extent_writer.h
index a6b3257..5e50256 100644
--- a/payload_consumer/xz_extent_writer.h
+++ b/payload_consumer/xz_extent_writer.h
@@ -20,7 +20,7 @@
 #include <xz.h>
 
 #include <memory>
-#include <vector>
+#include <utility>
 
 #include <brillo/secure_blob.h>
 
@@ -40,7 +40,7 @@
   ~XzExtentWriter() override;
 
   bool Init(FileDescriptorPtr fd,
-            const std::vector<Extent>& extents,
+            const google::protobuf::RepeatedPtrField<Extent>& extents,
             uint32_t block_size) override;
   bool Write(const void* bytes, size_t count) override;
   bool EndImpl() override;
diff --git a/payload_consumer/xz_extent_writer_unittest.cc b/payload_consumer/xz_extent_writer_unittest.cc
index fb8bb40..c8bcdf9 100644
--- a/payload_consumer/xz_extent_writer_unittest.cc
+++ b/payload_consumer/xz_extent_writer_unittest.cc
@@ -22,19 +22,14 @@
 #include <unistd.h>
 
 #include <algorithm>
-#include <string>
-#include <vector>
 
-#include <brillo/make_unique_ptr.h>
+#include <base/memory/ptr_util.h>
 #include <gtest/gtest.h>
 
 #include "update_engine/common/test_utils.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/payload_consumer/fake_extent_writer.h"
 
-using std::string;
-using std::vector;
-
 namespace chromeos_update_engine {
 
 namespace {
@@ -88,8 +83,7 @@
  protected:
   void SetUp() override {
     fake_extent_writer_ = new FakeExtentWriter();
-    xz_writer_.reset(
-        new XzExtentWriter(brillo::make_unique_ptr(fake_extent_writer_)));
+    xz_writer_.reset(new XzExtentWriter(base::WrapUnique(fake_extent_writer_)));
   }
 
   void WriteAll(const brillo::Blob& compressed) {
diff --git a/payload_generator/ab_generator.cc b/payload_generator/ab_generator.cc
index 3b0d012..089dfd9 100644
--- a/payload_generator/ab_generator.cc
+++ b/payload_generator/ab_generator.cc
@@ -17,6 +17,7 @@
 #include "update_engine/payload_generator/ab_generator.h"
 
 #include <algorithm>
+#include <utility>
 
 #include <base/strings/stringprintf.h>
 
@@ -173,7 +174,6 @@
     InstallOperation new_op;
     *(new_op.add_dst_extents()) = dst_ext;
     uint32_t data_size = dst_ext.num_blocks() * kBlockSize;
-    new_op.set_dst_length(data_size);
     // If this is a REPLACE, attempt to reuse portions of the existing blob.
     if (is_replace) {
       new_op.set_type(InstallOperation::REPLACE);
@@ -238,15 +238,9 @@
       if (is_delta_op) {
         ExtendExtents(last_aop.op.mutable_src_extents(),
                       curr_aop.op.src_extents());
-        if (curr_aop.op.src_length() > 0)
-          last_aop.op.set_src_length(last_aop.op.src_length() +
-                                     curr_aop.op.src_length());
       }
       ExtendExtents(last_aop.op.mutable_dst_extents(),
                     curr_aop.op.dst_extents());
-      if (curr_aop.op.dst_length() > 0)
-        last_aop.op.set_dst_length(last_aop.op.dst_length() +
-                                   curr_aop.op.dst_length());
       // Set the data length to zero so we know to add the blob later.
       if (is_a_replace)
         last_aop.op.set_data_length(0);
@@ -276,9 +270,9 @@
                                     BlobFileWriter* blob_file) {
   TEST_AND_RETURN_FALSE(IsAReplaceOperation(aop->op.type()));
 
-  brillo::Blob data(aop->op.dst_length());
   vector<Extent> dst_extents;
   ExtentsToVector(aop->op.dst_extents(), &dst_extents);
+  brillo::Blob data(utils::BlocksInExtents(dst_extents) * kBlockSize);
   TEST_AND_RETURN_FALSE(utils::ReadExtents(target_part_path,
                                            dst_extents,
                                            &data,
@@ -312,7 +306,7 @@
     uint64_t src_length =
         aop.op.has_src_length()
             ? aop.op.src_length()
-            : BlocksInExtents(aop.op.src_extents()) * kBlockSize;
+            : utils::BlocksInExtents(aop.op.src_extents()) * kBlockSize;
     TEST_AND_RETURN_FALSE(utils::ReadExtents(
         source_part_path, src_extents, &src_data, src_length, kBlockSize));
     TEST_AND_RETURN_FALSE(HashCalculator::RawHashOfData(src_data, &src_hash));
diff --git a/payload_generator/ab_generator.h b/payload_generator/ab_generator.h
index 77afb87..343b546 100644
--- a/payload_generator/ab_generator.h
+++ b/payload_generator/ab_generator.h
@@ -55,13 +55,13 @@
       BlobFileWriter* blob_file,
       std::vector<AnnotatedOperation>* aops) override;
 
-  // Split the operations in the vector of AnnotatedOperations |aops|
-  // such that for every operation there is only one dst extent and updates
-  // |aops| with the new list of operations. All kinds of operations are
-  // fragmented except BSDIFF and SOURCE_BSDIFF operations.
-  // The |target_part_path| is the filename of the new image, where the
-  // destination extents refer to. The blobs of the operations in |aops| should
-  // reference |blob_file|. |blob_file| are updated if needed.
+  // Split the operations in the vector of AnnotatedOperations |aops| such that
+  // for every operation there is only one dst extent and updates |aops| with
+  // the new list of operations. All kinds of operations are fragmented except
+  // BSDIFF and SOURCE_BSDIFF, PUFFDIFF and BROTLI_BSDIFF operations.  The
+  // |target_part_path| is the filename of the new image, where the destination
+  // extents refer to. The blobs of the operations in |aops| should reference
+  // |blob_file|. |blob_file| are updated if needed.
   static bool FragmentOperations(const PayloadVersion& version,
                                  std::vector<AnnotatedOperation>* aops,
                                  const std::string& target_part_path,
diff --git a/payload_generator/ab_generator_unittest.cc b/payload_generator/ab_generator_unittest.cc
index ab4b164..25609c7 100644
--- a/payload_generator/ab_generator_unittest.cc
+++ b/payload_generator/ab_generator_unittest.cc
@@ -42,7 +42,9 @@
 
 namespace {
 
-bool ExtentEquals(const Extent& ext, uint64_t start_block, uint64_t num_blocks) {
+bool ExtentEquals(const Extent& ext,
+                  uint64_t start_block,
+                  uint64_t num_blocks) {
   return ext.start_block() == start_block && ext.num_blocks() == num_blocks;
 }
 
@@ -85,7 +87,6 @@
                                            op_ex1_num_blocks);
   *(op.add_dst_extents()) = ExtentForRange(op_ex2_start_block,
                                            op_ex2_num_blocks);
-  op.set_dst_length(op_ex1_num_blocks + op_ex2_num_blocks);
 
   brillo::Blob op_data;
   op_data.insert(op_data.end(),
@@ -136,7 +137,8 @@
   EXPECT_EQ("SplitTestOp:0", result_ops[0].name);
   InstallOperation first_op = result_ops[0].op;
   EXPECT_EQ(expected_type, first_op.type());
-  EXPECT_EQ(op_ex1_size, first_op.dst_length());
+  EXPECT_FALSE(first_op.has_src_length());
+  EXPECT_FALSE(first_op.has_dst_length());
   EXPECT_EQ(1, first_op.dst_extents().size());
   EXPECT_TRUE(ExtentEquals(first_op.dst_extents(0), op_ex1_start_block,
                            op_ex1_num_blocks));
@@ -165,7 +167,8 @@
   EXPECT_EQ("SplitTestOp:1", result_ops[1].name);
   InstallOperation second_op = result_ops[1].op;
   EXPECT_EQ(expected_type, second_op.type());
-  EXPECT_EQ(op_ex2_size, second_op.dst_length());
+  EXPECT_FALSE(second_op.has_src_length());
+  EXPECT_FALSE(second_op.has_dst_length());
   EXPECT_EQ(1, second_op.dst_extents().size());
   EXPECT_TRUE(ExtentEquals(second_op.dst_extents(0), op_ex2_start_block,
                            op_ex2_num_blocks));
@@ -235,7 +238,6 @@
   InstallOperation first_op;
   first_op.set_type(orig_type);
   const size_t first_op_size = first_op_num_blocks * kBlockSize;
-  first_op.set_dst_length(first_op_size);
   *(first_op.add_dst_extents()) = ExtentForRange(0, first_op_num_blocks);
   brillo::Blob first_op_data(part_data.begin(),
                                part_data.begin() + first_op_size);
@@ -255,8 +257,6 @@
 
   InstallOperation second_op;
   second_op.set_type(orig_type);
-  const size_t second_op_size = second_op_num_blocks * kBlockSize;
-  second_op.set_dst_length(second_op_size);
   *(second_op.add_dst_extents()) = ExtentForRange(first_op_num_blocks,
                                                   second_op_num_blocks);
   brillo::Blob second_op_data(part_data.begin() + first_op_size,
@@ -302,7 +302,7 @@
   InstallOperation new_op = aops[0].op;
   EXPECT_EQ(expected_op_type, new_op.type());
   EXPECT_FALSE(new_op.has_src_length());
-  EXPECT_EQ(total_op_num_blocks * kBlockSize, new_op.dst_length());
+  EXPECT_FALSE(new_op.has_dst_length());
   EXPECT_EQ(1, new_op.dst_extents().size());
   EXPECT_TRUE(ExtentEquals(new_op.dst_extents(0), 0, total_op_num_blocks));
   EXPECT_EQ("first,second", aops[0].name);
diff --git a/payload_generator/deflate_utils.cc b/payload_generator/deflate_utils.cc
new file mode 100644
index 0000000..88e42e0
--- /dev/null
+++ b/payload_generator/deflate_utils.cc
@@ -0,0 +1,295 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/payload_generator/deflate_utils.h"
+
+#include <algorithm>
+#include <string>
+#include <utility>
+
+#include <base/files/file_util.h>
+#include <base/logging.h>
+#include <base/strings/string_util.h>
+
+#include "update_engine/common/utils.h"
+#include "update_engine/payload_generator/delta_diff_generator.h"
+#include "update_engine/payload_generator/extent_ranges.h"
+#include "update_engine/payload_generator/extent_utils.h"
+#include "update_engine/payload_generator/squashfs_filesystem.h"
+#include "update_engine/update_metadata.pb.h"
+
+using std::string;
+using std::vector;
+using puffin::BitExtent;
+using puffin::ByteExtent;
+
+namespace chromeos_update_engine {
+namespace deflate_utils {
+namespace {
+
+// The minimum size for a squashfs image to be processed.
+const uint64_t kMinimumSquashfsImageSize = 1 * 1024 * 1024;  // bytes
+
+// TODO(*): Optimize this so we don't have to read all extents into memory in
+// case it is large.
+bool CopyExtentsToFile(const string& in_path,
+                       const vector<Extent> extents,
+                       const string& out_path,
+                       size_t block_size) {
+  brillo::Blob data(utils::BlocksInExtents(extents) * block_size);
+  TEST_AND_RETURN_FALSE(
+      utils::ReadExtents(in_path, extents, &data, data.size(), block_size));
+  TEST_AND_RETURN_FALSE(
+      utils::WriteFile(out_path.c_str(), data.data(), data.size()));
+  return true;
+}
+
+bool IsSquashfsImage(const string& part_path,
+                     const FilesystemInterface::File& file) {
+  // Only check for files with img postfix.
+  if (base::EndsWith(file.name, ".img", base::CompareCase::SENSITIVE) &&
+      utils::BlocksInExtents(file.extents) >=
+          kMinimumSquashfsImageSize / kBlockSize) {
+    brillo::Blob super_block;
+    TEST_AND_RETURN_FALSE(
+        utils::ReadFileChunk(part_path,
+                             file.extents[0].start_block() * kBlockSize,
+                             100,
+                             &super_block));
+    return SquashfsFilesystem::IsSquashfsImage(super_block);
+  }
+  return false;
+}
+
+// Realigns subfiles |files| of a splitted file |file| into its correct
+// positions. This can be used for squashfs, zip, apk, etc.
+bool RealignSplittedFiles(const FilesystemInterface::File& file,
+                          vector<FilesystemInterface::File>* files) {
+  // We have to shift all the Extents in |files|, based on the Extents of the
+  // |file| itself.
+  size_t num_blocks = 0;
+  for (auto& in_file : *files) {  // We need to modify so no constant.
+    TEST_AND_RETURN_FALSE(
+        ShiftExtentsOverExtents(file.extents, &in_file.extents));
+    TEST_AND_RETURN_FALSE(
+        ShiftBitExtentsOverExtents(file.extents, &in_file.deflates));
+
+    in_file.name = file.name + "/" + in_file.name;
+    num_blocks += utils::BlocksInExtents(in_file.extents);
+  }
+
+  // Check that all files in |in_files| cover the entire image.
+  TEST_AND_RETURN_FALSE(utils::BlocksInExtents(file.extents) == num_blocks);
+  return true;
+}
+
+bool IsBitExtentInExtent(const Extent& extent, const BitExtent& bit_extent) {
+  return (bit_extent.offset / 8) >= (extent.start_block() * kBlockSize) &&
+         ((bit_extent.offset + bit_extent.length + 7) / 8) <=
+             ((extent.start_block() + extent.num_blocks()) * kBlockSize);
+}
+
+}  // namespace
+
+ByteExtent ExpandToByteExtent(const BitExtent& extent) {
+  uint64_t offset = extent.offset / 8;
+  uint64_t length = ((extent.offset + extent.length + 7) / 8) - offset;
+  return {offset, length};
+}
+
+bool ShiftExtentsOverExtents(const vector<Extent>& base_extents,
+                             vector<Extent>* over_extents) {
+  if (utils::BlocksInExtents(base_extents) <
+      utils::BlocksInExtents(*over_extents)) {
+    LOG(ERROR) << "over_extents have more blocks than base_extents! Invalid!";
+    return false;
+  }
+  for (size_t idx = 0; idx < over_extents->size(); idx++) {
+    auto over_ext = &over_extents->at(idx);
+    auto gap_blocks = base_extents[0].start_block();
+    auto last_end_block = base_extents[0].start_block();
+    for (auto base_ext : base_extents) {  // We need to modify |base_ext|, so we
+                                          // use copy.
+      gap_blocks += base_ext.start_block() - last_end_block;
+      last_end_block = base_ext.start_block() + base_ext.num_blocks();
+      base_ext.set_start_block(base_ext.start_block() - gap_blocks);
+      if (over_ext->start_block() >= base_ext.start_block() &&
+          over_ext->start_block() <
+              base_ext.start_block() + base_ext.num_blocks()) {
+        if (over_ext->start_block() + over_ext->num_blocks() <=
+            base_ext.start_block() + base_ext.num_blocks()) {
+          // |over_ext| is inside |base_ext|, increase its start block.
+          over_ext->set_start_block(over_ext->start_block() + gap_blocks);
+        } else {
+          // |over_ext| spills over this |base_ext|, split it into two.
+          auto new_blocks = base_ext.start_block() + base_ext.num_blocks() -
+                            over_ext->start_block();
+          vector<Extent> new_extents = {
+              ExtentForRange(gap_blocks + over_ext->start_block(), new_blocks),
+              ExtentForRange(over_ext->start_block() + new_blocks,
+                             over_ext->num_blocks() - new_blocks)};
+          *over_ext = new_extents[0];
+          over_extents->insert(std::next(over_extents->begin(), idx + 1),
+                               new_extents[1]);
+        }
+        break;  // We processed |over_ext|, so break the loop;
+      }
+    }
+  }
+  return true;
+}
+
+bool ShiftBitExtentsOverExtents(const vector<Extent>& base_extents,
+                                vector<BitExtent>* over_extents) {
+  if (over_extents->empty()) {
+    return true;
+  }
+
+  // This check is needed to make sure the number of bytes in |over_extents|
+  // does not exceed |base_extents|.
+  auto last_extent = ExpandToByteExtent(over_extents->back());
+  TEST_AND_RETURN_FALSE(last_extent.offset + last_extent.length <=
+                        utils::BlocksInExtents(base_extents) * kBlockSize);
+
+  for (auto o_ext = over_extents->begin(); o_ext != over_extents->end();) {
+    size_t gap_blocks = base_extents[0].start_block();
+    size_t last_end_block = base_extents[0].start_block();
+    bool o_ext_processed = false;
+    for (auto b_ext : base_extents) {  // We need to modify |b_ext|, so we copy.
+      gap_blocks += b_ext.start_block() - last_end_block;
+      last_end_block = b_ext.start_block() + b_ext.num_blocks();
+      b_ext.set_start_block(b_ext.start_block() - gap_blocks);
+      auto byte_o_ext = ExpandToByteExtent(*o_ext);
+      if (byte_o_ext.offset >= b_ext.start_block() * kBlockSize &&
+          byte_o_ext.offset <
+              (b_ext.start_block() + b_ext.num_blocks()) * kBlockSize) {
+        if ((byte_o_ext.offset + byte_o_ext.length) <=
+            (b_ext.start_block() + b_ext.num_blocks()) * kBlockSize) {
+          // |o_ext| is inside |b_ext|, increase its start block.
+          o_ext->offset += gap_blocks * kBlockSize * 8;
+          ++o_ext;
+        } else {
+          // |o_ext| spills over this |b_ext|, remove it.
+          o_ext = over_extents->erase(o_ext);
+        }
+        o_ext_processed = true;
+        break;  // We processed o_ext, so break the loop;
+      }
+    }
+    TEST_AND_RETURN_FALSE(o_ext_processed);
+  }
+  return true;
+}
+
+vector<BitExtent> FindDeflates(const vector<Extent>& extents,
+                               const vector<BitExtent>& in_deflates) {
+  vector<BitExtent> result;
+  // TODO(ahassani): Replace this with binary_search style search.
+  for (const auto& deflate : in_deflates) {
+    for (const auto& extent : extents) {
+      if (IsBitExtentInExtent(extent, deflate)) {
+        result.push_back(deflate);
+        break;
+      }
+    }
+  }
+  return result;
+}
+
+bool CompactDeflates(const vector<Extent>& extents,
+                     const vector<BitExtent>& in_deflates,
+                     vector<BitExtent>* out_deflates) {
+  size_t bytes_passed = 0;
+  out_deflates->reserve(in_deflates.size());
+  for (const auto& extent : extents) {
+    size_t gap_bytes = extent.start_block() * kBlockSize - bytes_passed;
+    for (const auto& deflate : in_deflates) {
+      if (IsBitExtentInExtent(extent, deflate)) {
+        out_deflates->emplace_back(deflate.offset - (gap_bytes * 8),
+                                   deflate.length);
+      }
+    }
+    bytes_passed += extent.num_blocks() * kBlockSize;
+  }
+
+  // All given |in_deflates| items should've been inside one of the extents in
+  // |extents|.
+  TEST_AND_RETURN_FALSE(in_deflates.size() == out_deflates->size());
+
+  // Make sure all outgoing deflates are ordered and non-overlapping.
+  auto result = std::adjacent_find(out_deflates->begin(),
+                                   out_deflates->end(),
+                                   [](const BitExtent& a, const BitExtent& b) {
+                                     return (a.offset + a.length) > b.offset;
+                                   });
+  TEST_AND_RETURN_FALSE(result == out_deflates->end());
+  return true;
+}
+
+bool FindAndCompactDeflates(const vector<Extent>& extents,
+                            const vector<BitExtent>& in_deflates,
+                            vector<BitExtent>* out_deflates) {
+  auto found_deflates = FindDeflates(extents, in_deflates);
+  TEST_AND_RETURN_FALSE(CompactDeflates(extents, found_deflates, out_deflates));
+  return true;
+}
+
+bool PreprocessParitionFiles(const PartitionConfig& part,
+                             vector<FilesystemInterface::File>* result_files,
+                             bool extract_deflates) {
+  // Get the file system files.
+  vector<FilesystemInterface::File> tmp_files;
+  part.fs_interface->GetFiles(&tmp_files);
+  result_files->reserve(tmp_files.size());
+
+  for (const auto& file : tmp_files) {
+    if (IsSquashfsImage(part.path, file)) {
+      // Read the image into a file.
+      base::FilePath path;
+      TEST_AND_RETURN_FALSE(base::CreateTemporaryFile(&path));
+      ScopedPathUnlinker old_unlinker(path.value());
+      TEST_AND_RETURN_FALSE(
+          CopyExtentsToFile(part.path, file.extents, path.value(), kBlockSize));
+      // Test if it is actually a Squashfs file.
+      auto sqfs =
+          SquashfsFilesystem::CreateFromFile(path.value(), extract_deflates);
+      if (sqfs) {
+        // It is an squashfs file. Get its files to replace with itself.
+        vector<FilesystemInterface::File> files;
+        sqfs->GetFiles(&files);
+
+        // Replace squashfs file with its files only if |files| has at least two
+        // files or if it has some deflates (since it is better to replace it to
+        // take advantage of the deflates.)
+        if (files.size() > 1 ||
+            (files.size() == 1 && !files[0].deflates.empty())) {
+          TEST_AND_RETURN_FALSE(RealignSplittedFiles(file, &files));
+          result_files->insert(result_files->end(), files.begin(), files.end());
+          continue;
+        }
+      } else {
+        LOG(WARNING) << "We thought file: " << file.name
+                     << " was a Squashfs file, but it was not.";
+      }
+    }
+    // TODO(ahassani): Process other types of files like apk, zip, etc.
+    result_files->push_back(file);
+  }
+  return true;
+}
+
+}  // namespace deflate_utils
+}  // namespace chromeos_update_engine
diff --git a/payload_generator/deflate_utils.h b/payload_generator/deflate_utils.h
new file mode 100644
index 0000000..798ce25
--- /dev/null
+++ b/payload_generator/deflate_utils.h
@@ -0,0 +1,97 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_PAYLOAD_GENERATOR_DEFLATE_UTILS_H_
+#define UPDATE_ENGINE_PAYLOAD_GENERATOR_DEFLATE_UTILS_H_
+
+#include <puffin/puffdiff.h>
+#include <vector>
+
+#include "update_engine/payload_generator/filesystem_interface.h"
+#include "update_engine/payload_generator/payload_generation_config.h"
+
+namespace chromeos_update_engine {
+namespace deflate_utils {
+
+// Gets the files from the partition and processes all its files. Processing
+// includes:
+//  - splitting large Squashfs containers into its smaller files.
+bool PreprocessParitionFiles(const PartitionConfig& part,
+                             std::vector<FilesystemInterface::File>* result,
+                             bool extract_deflates);
+
+// Spreads all extents in |over_extents| over |base_extents|. Here we assume the
+// |over_extents| are non-overlapping and sorted by their offset.
+//
+// |base_extents|:
+// |               -----------------------        ------         --------------
+// |over_extents|:
+// |  ==========  ====    ==========  ======
+// |over_extents| is transforms to:
+// |                 ==========  ====    =        ======         ===  ======
+//
+bool ShiftExtentsOverExtents(const std::vector<Extent>& base_extents,
+                             std::vector<Extent>* over_extents);
+
+// Spreads all extents in |over_extents| over |base_extents|. Here we assume the
+// |over_extents| are non-overlapping and sorted by their offset. An item in
+// |over_extents| is removed if it is spread in two or more extents in
+// |base_extents|.
+//
+// |base_extents|:
+// |               -----------------------        ------         --------------
+// |over_extents|:
+// |  ==========  ====    ==========  ======
+// |over_extents| is transforms to:
+// |                 ==========  ====                                 ======
+//
+bool ShiftBitExtentsOverExtents(const std::vector<Extent>& base_extents,
+                                std::vector<puffin::BitExtent>* over_extents);
+
+// Finds all deflate locations in |deflates| that are inside an Extent in
+// |extents|. This function should not change the order of deflates.
+std::vector<puffin::BitExtent> FindDeflates(
+    const std::vector<Extent>& extents,
+    const std::vector<puffin::BitExtent>& deflates);
+
+// Creates a new list of deflate locations (|out_deflates|) from |in_deflates|
+// by assuming all extents in the |extents| have been put together
+// linearly. This function assumes that all deflate locations given in
+// |in_deflates| are located somewhere in the |extents|. |out_deflates| should
+// be empty on call.
+//
+// |extents|:
+// |               -----------------------        ------         --------------
+// |in_deflates|:
+// |                   ========  ====              ====           ======
+// |out_deflates|:
+// |    ========  ====      ====  ======
+//
+bool CompactDeflates(const std::vector<Extent>& extents,
+                     const std::vector<puffin::BitExtent>& in_deflates,
+                     std::vector<puffin::BitExtent>* out_deflates);
+
+// Combines |FindDeflates| and |CompcatDeflates| for ease of use.
+bool FindAndCompactDeflates(const std::vector<Extent>& extents,
+                            const std::vector<puffin::BitExtent>& in_deflates,
+                            std::vector<puffin::BitExtent>* out_deflates);
+
+// Expands a BitExtents to a ByteExtent.
+puffin::ByteExtent ExpandToByteExtent(const puffin::BitExtent& extent);
+
+}  // namespace deflate_utils
+}  // namespace chromeos_update_engine
+#endif  // UPDATE_ENGINE_PAYLOAD_GENERATOR_DEFLATE_UTILS_H_
diff --git a/payload_generator/deflate_utils_unittest.cc b/payload_generator/deflate_utils_unittest.cc
new file mode 100644
index 0000000..cb9476a
--- /dev/null
+++ b/payload_generator/deflate_utils_unittest.cc
@@ -0,0 +1,190 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/payload_generator/deflate_utils.h"
+
+#include <unistd.h>
+
+#include <algorithm>
+#include <utility>
+#include <vector>
+
+#include <gtest/gtest.h>
+
+#include "update_engine/common/test_utils.h"
+#include "update_engine/common/utils.h"
+#include "update_engine/payload_generator/extent_ranges.h"
+#include "update_engine/payload_generator/extent_utils.h"
+
+using std::vector;
+using puffin::BitExtent;
+using puffin::ByteExtent;
+
+namespace chromeos_update_engine {
+namespace deflate_utils {
+
+// This creates a sudo-random BitExtents from ByteExtents for simpler testing.
+vector<BitExtent> ByteToBitExtent(const vector<ByteExtent>& byte_extents) {
+  vector<BitExtent> bit_extents;
+  for (auto& byte_extent : byte_extents) {
+    bit_extents.emplace_back(byte_extent.offset * 8 + (byte_extent.offset & 7),
+                             byte_extent.length * 8 - (byte_extent.length & 7));
+  }
+  return bit_extents;
+}
+
+TEST(DeflateUtilsTest, ExtentsShiftTest) {
+  vector<Extent> base_extents = {ExtentForRange(10, 10),
+                                 ExtentForRange(70, 10),
+                                 ExtentForRange(50, 10),
+                                 ExtentForRange(30, 10),
+                                 ExtentForRange(90, 10)};
+  vector<Extent> over_extents = {ExtentForRange(2, 2),
+                                 ExtentForRange(5, 2),
+                                 ExtentForRange(7, 3),
+                                 ExtentForRange(13, 10),
+                                 ExtentForRange(25, 20),
+                                 ExtentForRange(47, 3)};
+  vector<Extent> out_over_extents = {ExtentForRange(12, 2),
+                                     ExtentForRange(15, 2),
+                                     ExtentForRange(17, 3),
+                                     ExtentForRange(73, 7),
+                                     ExtentForRange(50, 3),
+                                     ExtentForRange(55, 5),
+                                     ExtentForRange(30, 10),
+                                     ExtentForRange(90, 5),
+                                     ExtentForRange(97, 3)};
+  EXPECT_TRUE(ShiftExtentsOverExtents(base_extents, &over_extents));
+  EXPECT_EQ(over_extents, out_over_extents);
+
+  // Failure case
+  base_extents = {ExtentForRange(10, 10)};
+  over_extents = {ExtentForRange(2, 12)};
+  EXPECT_FALSE(ShiftExtentsOverExtents(base_extents, &over_extents));
+}
+
+TEST(DeflateUtilsTest, ShiftBitExtentsOverExtentsTest) {
+  vector<Extent> base_extents = {ExtentForRange(3, 1),
+                                 ExtentForRange(1, 1),
+                                 ExtentForRange(5, 1),
+                                 ExtentForRange(7, 1),
+                                 ExtentForRange(9, 1)};
+  vector<BitExtent> over_extents =
+      ByteToBitExtent({{0, 0}, {100, 2000}, {4096, 0}, {5000, 5000}});
+  vector<BitExtent> out_over_extents =
+      ByteToBitExtent({{12288, 0}, {12388, 2000}, {4096, 0}});
+  ASSERT_TRUE(ShiftBitExtentsOverExtents(base_extents, &over_extents));
+  EXPECT_EQ(over_extents, out_over_extents);
+}
+
+TEST(DeflateUtilsTest, ShiftBitExtentsOverExtentsBoundaryTest) {
+  vector<Extent> base_extents = {ExtentForRange(1, 1)};
+  vector<BitExtent> over_extents = ByteToBitExtent({{2, 4096}});
+  vector<BitExtent> out_over_extents = {};
+  EXPECT_FALSE(ShiftBitExtentsOverExtents(base_extents, &over_extents));
+
+  base_extents = {ExtentForRange(1, 1)};
+  over_extents = {};
+  out_over_extents = {};
+  EXPECT_TRUE(ShiftBitExtentsOverExtents(base_extents, &over_extents));
+  EXPECT_EQ(over_extents, out_over_extents);
+
+  base_extents = {};
+  over_extents = {};
+  out_over_extents = {};
+  EXPECT_TRUE(ShiftBitExtentsOverExtents(base_extents, &over_extents));
+  EXPECT_EQ(over_extents, out_over_extents);
+
+  base_extents = {};
+  over_extents = ByteToBitExtent({{0, 1}});
+  out_over_extents = ByteToBitExtent({{0, 1}});
+  EXPECT_FALSE(ShiftBitExtentsOverExtents(base_extents, &over_extents));
+  EXPECT_EQ(over_extents, out_over_extents);
+
+  base_extents = {ExtentForRange(1, 2)};
+  over_extents = ByteToBitExtent({{0, 3 * 4096}, {4 * 4096, 4096}});
+  out_over_extents = ByteToBitExtent({{0, 3 * 4096}, {4 * 4096, 4096}});
+  EXPECT_FALSE(ShiftBitExtentsOverExtents(base_extents, &over_extents));
+  EXPECT_EQ(over_extents, out_over_extents);
+}
+
+TEST(DeflateUtilsTest, FindDeflatesTest) {
+  vector<Extent> extents = {
+      ExtentForRange(1, 1), ExtentForRange(3, 1), ExtentForRange(5, 1)};
+  vector<BitExtent> in_deflates = ByteToBitExtent({{0, 0},
+                                                   {10, 400},
+                                                   {4096, 0},
+                                                   {3000, 2000},
+                                                   {4096, 100},
+                                                   {4097, 100},
+                                                   {8100, 92},
+                                                   {8100, 93},
+                                                   {8100, 6000},
+                                                   {25000, 1}});
+  vector<BitExtent> expected_out_deflates =
+      ByteToBitExtent({{4096, 0}, {4096, 100}, {4097, 100}, {8100, 92}});
+  vector<BitExtent> out_deflates;
+  out_deflates = FindDeflates(extents, in_deflates);
+  EXPECT_EQ(out_deflates, expected_out_deflates);
+}
+
+TEST(DeflateUtilsTest, FindDeflatesBoundaryTest) {
+  vector<Extent> extents = {};
+  vector<BitExtent> in_deflates = ByteToBitExtent({{0, 0}, {8100, 93}});
+  vector<BitExtent> expected_out_deflates = {};
+  vector<BitExtent> out_deflates;
+  out_deflates = FindDeflates(extents, in_deflates);
+  EXPECT_EQ(out_deflates, expected_out_deflates);
+
+  extents = {};
+  in_deflates = {};
+  out_deflates = FindDeflates(extents, in_deflates);
+  EXPECT_EQ(out_deflates, expected_out_deflates);
+}
+
+TEST(DeflateUtilsTest, CompactTest) {
+  vector<Extent> extents = {
+      ExtentForRange(1, 1), ExtentForRange(5, 1), ExtentForRange(3, 1)};
+  vector<BitExtent> in_deflates =
+      ByteToBitExtent({{4096, 0}, {12288, 4096}, {4096, 100}, {20480, 100}});
+  vector<BitExtent> expected_out_deflates =
+      ByteToBitExtent({{0, 0}, {0, 100}, {4096, 100}, {8192, 4096}});
+  vector<BitExtent> out_deflates;
+  ASSERT_TRUE(CompactDeflates(extents, in_deflates, &out_deflates));
+  EXPECT_EQ(out_deflates, expected_out_deflates);
+}
+
+TEST(DeflateUtilsTest, CompactBoundaryTest) {
+  vector<Extent> extents = {};
+  vector<BitExtent> in_deflates = ByteToBitExtent({{4096, 0}});
+  vector<BitExtent> expected_out_deflates = {};
+  vector<BitExtent> out_deflates;
+  EXPECT_FALSE(CompactDeflates(extents, in_deflates, &out_deflates));
+  EXPECT_EQ(out_deflates, expected_out_deflates);
+
+  extents = {};
+  in_deflates = {};
+  ASSERT_TRUE(CompactDeflates(extents, in_deflates, &out_deflates));
+  EXPECT_EQ(out_deflates, expected_out_deflates);
+
+  extents = {ExtentForRange(1, 1)};
+  in_deflates = {};
+  ASSERT_TRUE(CompactDeflates(extents, in_deflates, &out_deflates));
+  EXPECT_EQ(out_deflates, expected_out_deflates);
+}
+
+}  // namespace deflate_utils
+}  // namespace chromeos_update_engine
diff --git a/payload_generator/delta_diff_utils.cc b/payload_generator/delta_diff_utils.cc
index e928912..bcbc3a5 100644
--- a/payload_generator/delta_diff_utils.cc
+++ b/payload_generator/delta_diff_utils.cc
@@ -17,30 +17,41 @@
 #include "update_engine/payload_generator/delta_diff_utils.h"
 
 #include <endian.h>
-// TODO: Remove these pragmas when b/35721782 is fixed.
+#if defined(__clang__)
+// TODO(*): Remove these pragmas when b/35721782 is fixed.
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wmacro-redefined"
+#endif
 #include <ext2fs/ext2fs.h>
+#if defined(__clang__)
 #pragma clang diagnostic pop
+#endif
 #include <unistd.h>
 
 #include <algorithm>
 #include <map>
+#include <memory>
+#include <utility>
 
 #include <base/files/file_util.h>
 #include <base/format_macros.h>
+#include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
 #include <base/threading/simple_thread.h>
 #include <brillo/data_encoding.h>
+#include <bsdiff/bsdiff.h>
 
 #include "update_engine/common/hash_calculator.h"
 #include "update_engine/common/subprocess.h"
 #include "update_engine/common/utils.h"
+#include "update_engine/payload_consumer/payload_constants.h"
 #include "update_engine/payload_generator/block_mapping.h"
 #include "update_engine/payload_generator/bzip.h"
+#include "update_engine/payload_generator/deflate_utils.h"
 #include "update_engine/payload_generator/delta_diff_generator.h"
 #include "update_engine/payload_generator/extent_ranges.h"
 #include "update_engine/payload_generator/extent_utils.h"
+#include "update_engine/payload_generator/squashfs_filesystem.h"
 #include "update_engine/payload_generator/xz.h"
 
 using std::map;
@@ -50,9 +61,6 @@
 namespace chromeos_update_engine {
 namespace {
 
-const char* const kBsdiffPath = "bsdiff";
-const char* const kImgdiffPath = "imgdiff";
-
 // The maximum destination size allowed for bsdiff. In general, bsdiff should
 // work for arbitrary big files, but the payload generation and payload
 // application requires a significant amount of RAM. We put a hard-limit of
@@ -60,10 +68,10 @@
 // Chrome binary in ASan builders.
 const uint64_t kMaxBsdiffDestinationSize = 200 * 1024 * 1024;  // bytes
 
-// The maximum destination size allowed for imgdiff. In general, imgdiff should
-// work for arbitrary big files, but the payload application is quite memory
-// intensive, so we limit these operations to 50 MiB.
-const uint64_t kMaxImgdiffDestinationSize = 50 * 1024 * 1024;  // bytes
+// The maximum destination size allowed for puffdiff. In general, puffdiff
+// should work for arbitrary big files, but the payload application is quite
+// memory intensive, so we limit these operations to 150 MiB.
+const uint64_t kMaxPuffdiffDestinationSize = 150 * 1024 * 1024;  // bytes
 
 // Process a range of blocks from |range_start| to |range_end| in the extent at
 // position |*idx_p| of |extents|. If |do_remove| is true, this range will be
@@ -160,15 +168,6 @@
   return removed_bytes;
 }
 
-// Returns true if the given blob |data| contains gzip header magic.
-bool ContainsGZip(const brillo::Blob& data) {
-  const uint8_t kGZipMagic[] = {0x1f, 0x8b, 0x08, 0x00};
-  return std::search(data.begin(),
-                     data.end(),
-                     std::begin(kGZipMagic),
-                     std::end(kGZipMagic)) != data.end();
-}
-
 }  // namespace
 
 namespace diff_utils {
@@ -183,6 +182,8 @@
                      const PayloadVersion& version,
                      const vector<Extent>& old_extents,
                      const vector<Extent>& new_extents,
+                     const vector<puffin::BitExtent>& old_deflates,
+                     const vector<puffin::BitExtent>& new_deflates,
                      const string& name,
                      ssize_t chunk_blocks,
                      BlobFileWriter* blob_file)
@@ -191,6 +192,8 @@
         version_(version),
         old_extents_(old_extents),
         new_extents_(new_extents),
+        old_deflates_(old_deflates),
+        new_deflates_(new_deflates),
         name_(name),
         chunk_blocks_(chunk_blocks),
         blob_file_(blob_file) {}
@@ -215,6 +218,8 @@
   // The block ranges of the old/new file within the src/tgt image
   const vector<Extent> old_extents_;
   const vector<Extent> new_extents_;
+  const vector<puffin::BitExtent> old_deflates_;
+  const vector<puffin::BitExtent> new_deflates_;
   const string name_;
   // Block limit of one aop.
   ssize_t chunk_blocks_;
@@ -229,17 +234,22 @@
 void FileDeltaProcessor::Run() {
   TEST_AND_RETURN(blob_file_ != nullptr);
 
+  LOG(INFO) << "Encoding file " << name_ << " ("
+            << utils::BlocksInExtents(new_extents_) << " blocks)";
+
   if (!DeltaReadFile(&file_aops_,
                      old_part_,
                      new_part_,
                      old_extents_,
                      new_extents_,
+                     old_deflates_,
+                     new_deflates_,
                      name_,
                      chunk_blocks_,
                      version_,
                      blob_file_)) {
     LOG(ERROR) << "Failed to generate delta for " << name_ << " ("
-               << BlocksInExtents(new_extents_) << " blocks)";
+               << utils::BlocksInExtents(new_extents_) << " blocks)";
   }
 }
 
@@ -270,17 +280,20 @@
       &old_visited_blocks,
       &new_visited_blocks));
 
-  map<string, vector<Extent>> old_files_map;
+  bool puffdiff_allowed = version.OperationAllowed(InstallOperation::PUFFDIFF);
+  map<string, FilesystemInterface::File> old_files_map;
   if (old_part.fs_interface) {
     vector<FilesystemInterface::File> old_files;
-    old_part.fs_interface->GetFiles(&old_files);
+    TEST_AND_RETURN_FALSE(deflate_utils::PreprocessParitionFiles(
+        old_part, &old_files, puffdiff_allowed));
     for (const FilesystemInterface::File& file : old_files)
-      old_files_map[file.name] = file.extents;
+      old_files_map[file.name] = file;
   }
 
   TEST_AND_RETURN_FALSE(new_part.fs_interface);
   vector<FilesystemInterface::File> new_files;
-  new_part.fs_interface->GetFiles(&new_files);
+  TEST_AND_RETURN_FALSE(deflate_utils::PreprocessParitionFiles(
+      new_part, &new_files, puffdiff_allowed));
 
   vector<FileDeltaProcessor> file_delta_processors;
 
@@ -303,9 +316,6 @@
     if (new_file_extents.empty())
       continue;
 
-    LOG(INFO) << "Encoding file " << new_file.name << " ("
-              << BlocksInExtents(new_file_extents) << " blocks)";
-
     // We can't visit each dst image inode more than once, as that would
     // duplicate work. Here, we avoid visiting each source image inode
     // more than once. Technically, we could have multiple operations
@@ -314,8 +324,9 @@
     // from using a graph/cycle detection/etc to generate diffs, and at that
     // time, it will be easy (non-complex) to have many operations read
     // from the same source blocks. At that time, this code can die. -adlr
-    vector<Extent> old_file_extents = FilterExtentRanges(
-        old_files_map[new_file.name], old_visited_blocks);
+    auto old_file = old_files_map[new_file.name];
+    vector<Extent> old_file_extents =
+        FilterExtentRanges(old_file.extents, old_visited_blocks);
     old_visited_blocks.AddExtents(old_file_extents);
 
     file_delta_processors.emplace_back(old_part.path,
@@ -323,6 +334,8 @@
                                        version,
                                        std::move(old_file_extents),
                                        std::move(new_file_extents),
+                                       old_file.deflates,
+                                       new_file.deflates,
                                        new_file.name,  // operation name
                                        hard_chunk_blocks,
                                        blob_file);
@@ -355,9 +368,9 @@
     old_unvisited = FilterExtentRanges(old_unvisited, old_visited_blocks);
   }
 
-  LOG(INFO) << "Scanning " << BlocksInExtents(new_unvisited)
-            << " unwritten blocks using chunk size of "
-            << soft_chunk_blocks << " blocks.";
+  LOG(INFO) << "Scanning " << utils::BlocksInExtents(new_unvisited)
+            << " unwritten blocks using chunk size of " << soft_chunk_blocks
+            << " blocks.";
   // We use the soft_chunk_blocks limit for the <non-file-data> as we don't
   // really know the structure of this data and we should not expect it to have
   // redundancy between partitions.
@@ -366,6 +379,8 @@
                                       new_part.path,
                                       old_unvisited,
                                       new_unvisited,
+                                      {},                 // old_deflates,
+                                      {},                 // new_deflates
                                       "<non-file-data>",  // operation name
                                       soft_chunk_blocks,
                                       version,
@@ -470,13 +485,15 @@
                                         new_part,
                                         vector<Extent>(),        // old_extents
                                         vector<Extent>{extent},  // new_extents
+                                        {},                      // old_deflates
+                                        {},                      // new_deflates
                                         "<zeros>",
                                         chunk_blocks,
                                         version,
                                         blob_file));
   }
   LOG(INFO) << "Produced " << (aops->size() - num_ops) << " operations for "
-            << BlocksInExtents(new_zeros) << " zeroed blocks";
+            << utils::BlocksInExtents(new_zeros) << " zeroed blocks";
 
   // Produce MOVE/SOURCE_COPY operations for the moved blocks.
   num_ops = aops->size();
@@ -530,6 +547,8 @@
                    const string& new_part,
                    const vector<Extent>& old_extents,
                    const vector<Extent>& new_extents,
+                   const vector<puffin::BitExtent>& old_deflates,
+                   const vector<puffin::BitExtent>& new_deflates,
                    const string& name,
                    ssize_t chunk_blocks,
                    const PayloadVersion& version,
@@ -537,7 +556,7 @@
   brillo::Blob data;
   InstallOperation operation;
 
-  uint64_t total_blocks = BlocksInExtents(new_extents);
+  uint64_t total_blocks = utils::BlocksInExtents(new_extents);
   if (chunk_blocks == -1)
     chunk_blocks = total_blocks;
 
@@ -558,6 +577,8 @@
                                             new_part,
                                             old_extents_chunk,
                                             new_extents_chunk,
+                                            old_deflates,
+                                            new_deflates,
                                             version,
                                             &data,
                                             &operation));
@@ -648,16 +669,18 @@
                        const string& new_part,
                        const vector<Extent>& old_extents,
                        const vector<Extent>& new_extents,
+                       const vector<puffin::BitExtent>& old_deflates,
+                       const vector<puffin::BitExtent>& new_deflates,
                        const PayloadVersion& version,
                        brillo::Blob* out_data,
                        InstallOperation* out_op) {
   InstallOperation operation;
 
   // We read blocks from old_extents and write blocks to new_extents.
-  uint64_t blocks_to_read = BlocksInExtents(old_extents);
-  uint64_t blocks_to_write = BlocksInExtents(new_extents);
+  uint64_t blocks_to_read = utils::BlocksInExtents(old_extents);
+  uint64_t blocks_to_write = utils::BlocksInExtents(new_extents);
 
-  // Disable bsdiff and imgdiff when the data is too big.
+  // Disable bsdiff, and puffdiff when the data is too big.
   bool bsdiff_allowed =
       version.OperationAllowed(InstallOperation::SOURCE_BSDIFF) ||
       version.OperationAllowed(InstallOperation::BSDIFF);
@@ -668,12 +691,12 @@
     bsdiff_allowed = false;
   }
 
-  bool imgdiff_allowed = version.OperationAllowed(InstallOperation::IMGDIFF);
-  if (imgdiff_allowed &&
-      blocks_to_read * kBlockSize > kMaxImgdiffDestinationSize) {
-    LOG(INFO) << "imgdiff blacklisted, data too big: "
+  bool puffdiff_allowed = version.OperationAllowed(InstallOperation::PUFFDIFF);
+  if (puffdiff_allowed &&
+      blocks_to_read * kBlockSize > kMaxPuffdiffDestinationSize) {
+    LOG(INFO) << "puffdiff blacklisted, data too big: "
               << blocks_to_read * kBlockSize << " bytes";
-    imgdiff_allowed = false;
+    puffdiff_allowed = false;
   }
 
   // Make copies of the extents so we can modify them.
@@ -711,24 +734,21 @@
                              ? InstallOperation::SOURCE_COPY
                              : InstallOperation::MOVE);
       data_blob = brillo::Blob();
-    } else if (bsdiff_allowed || imgdiff_allowed) {
-      // If the source file is considered bsdiff safe (no bsdiff bugs
-      // triggered), see if BSDIFF encoding is smaller.
-      base::FilePath old_chunk;
-      TEST_AND_RETURN_FALSE(base::CreateTemporaryFile(&old_chunk));
-      ScopedPathUnlinker old_unlinker(old_chunk.value());
-      TEST_AND_RETURN_FALSE(utils::WriteFile(
-          old_chunk.value().c_str(), old_data.data(), old_data.size()));
-      base::FilePath new_chunk;
-      TEST_AND_RETURN_FALSE(base::CreateTemporaryFile(&new_chunk));
-      ScopedPathUnlinker new_unlinker(new_chunk.value());
-      TEST_AND_RETURN_FALSE(utils::WriteFile(
-          new_chunk.value().c_str(), new_data.data(), new_data.size()));
-
+    } else {
       if (bsdiff_allowed) {
+        base::FilePath patch;
+        TEST_AND_RETURN_FALSE(base::CreateTemporaryFile(&patch));
+        ScopedPathUnlinker unlinker(patch.value());
+
         brillo::Blob bsdiff_delta;
-        TEST_AND_RETURN_FALSE(DiffFiles(
-            kBsdiffPath, old_chunk.value(), new_chunk.value(), &bsdiff_delta));
+        TEST_AND_RETURN_FALSE(0 == bsdiff::bsdiff(old_data.data(),
+                                                  old_data.size(),
+                                                  new_data.data(),
+                                                  new_data.size(),
+                                                  patch.value().c_str(),
+                                                  nullptr));
+
+        TEST_AND_RETURN_FALSE(utils::ReadFile(patch.value(), &bsdiff_delta));
         CHECK_GT(bsdiff_delta.size(), static_cast<brillo::Blob::size_type>(0));
         if (bsdiff_delta.size() < data_blob.size()) {
           operation.set_type(
@@ -738,82 +758,94 @@
           data_blob = std::move(bsdiff_delta);
         }
       }
-      if (imgdiff_allowed && ContainsGZip(old_data) && ContainsGZip(new_data)) {
-        brillo::Blob imgdiff_delta;
-        // Imgdiff might fail in some cases, only use the result if it succeed,
-        // otherwise print the extents to analyze.
-        if (DiffFiles(kImgdiffPath,
-                      old_chunk.value(),
-                      new_chunk.value(),
-                      &imgdiff_delta) &&
-            imgdiff_delta.size() > 0) {
-          if (imgdiff_delta.size() < data_blob.size()) {
-            operation.set_type(InstallOperation::IMGDIFF);
-            data_blob = std::move(imgdiff_delta);
+      if (puffdiff_allowed) {
+        // Find all deflate positions inside the given extents and then put all
+        // deflates together because we have already read all the extents into
+        // one buffer.
+        vector<puffin::BitExtent> src_deflates;
+        TEST_AND_RETURN_FALSE(deflate_utils::FindAndCompactDeflates(
+            src_extents, old_deflates, &src_deflates));
+
+        vector<puffin::BitExtent> dst_deflates;
+        TEST_AND_RETURN_FALSE(deflate_utils::FindAndCompactDeflates(
+            dst_extents, new_deflates, &dst_deflates));
+
+        // Remove equal deflates. TODO(*): We can do a N*N check using
+        // hashing. It will not reduce the payload size, but it will speeds up
+        // the puffing on the client device.
+        auto src = src_deflates.begin();
+        auto dst = dst_deflates.begin();
+        for (; src != src_deflates.end() && dst != dst_deflates.end();) {
+          auto src_in_bytes = deflate_utils::ExpandToByteExtent(*src);
+          auto dst_in_bytes = deflate_utils::ExpandToByteExtent(*dst);
+          if (src_in_bytes.length == dst_in_bytes.length &&
+              !memcmp(old_data.data() + src_in_bytes.offset,
+                      new_data.data() + dst_in_bytes.offset,
+                      src_in_bytes.length)) {
+            src = src_deflates.erase(src);
+            dst = dst_deflates.erase(dst);
+          } else {
+            src++;
+            dst++;
           }
-        } else {
-          LOG(ERROR) << "Imgdiff failed with source extents: "
-                     << ExtentsToString(src_extents)
-                     << ", destination extents: "
-                     << ExtentsToString(dst_extents);
+        }
+
+        // Only Puffdiff if both files have at least one deflate left.
+        if (!src_deflates.empty() && !dst_deflates.empty()) {
+          brillo::Blob puffdiff_delta;
+          string temp_file_path;
+          TEST_AND_RETURN_FALSE(utils::MakeTempFile(
+              "puffdiff-delta.XXXXXX", &temp_file_path, nullptr));
+          ScopedPathUnlinker temp_file_unlinker(temp_file_path);
+
+          // Perform PuffDiff operation.
+          TEST_AND_RETURN_FALSE(puffin::PuffDiff(old_data,
+                                                 new_data,
+                                                 src_deflates,
+                                                 dst_deflates,
+                                                 temp_file_path,
+                                                 &puffdiff_delta));
+          TEST_AND_RETURN_FALSE(puffdiff_delta.size() > 0);
+          if (puffdiff_delta.size() < data_blob.size()) {
+            operation.set_type(InstallOperation::PUFFDIFF);
+            data_blob = std::move(puffdiff_delta);
+          }
         }
       }
     }
   }
 
-  size_t removed_bytes = 0;
   // Remove identical src/dst block ranges in MOVE operations.
   if (operation.type() == InstallOperation::MOVE) {
-    removed_bytes = RemoveIdenticalBlockRanges(
+    auto removed_bytes = RemoveIdenticalBlockRanges(
         &src_extents, &dst_extents, new_data.size());
+    operation.set_src_length(old_data.size() - removed_bytes);
+    operation.set_dst_length(new_data.size() - removed_bytes);
   }
-  // Set legacy src_length and dst_length fields.
-  operation.set_src_length(old_data.size() - removed_bytes);
-  operation.set_dst_length(new_data.size() - removed_bytes);
 
-  // Embed extents in the operation.
-  StoreExtents(src_extents, operation.mutable_src_extents());
+  // WARNING: We always set legacy |src_length| and |dst_length| fields for
+  // BSDIFF. For SOURCE_BSDIFF we only set them for minor version 3 and
+  // lower. This is needed because we used to use these two parameters in the
+  // SOURCE_BSDIFF for minor version 3 and lower, but we do not need them
+  // anymore in higher minor versions. This means if we stop adding these
+  // parameters for those minor versions, the delta payloads will be invalid.
+  if (operation.type() == InstallOperation::BSDIFF ||
+      (operation.type() == InstallOperation::SOURCE_BSDIFF &&
+       version.minor <= kOpSrcHashMinorPayloadVersion)) {
+    operation.set_src_length(old_data.size());
+    operation.set_dst_length(new_data.size());
+  }
+
+  // Embed extents in the operation. Replace (all variants), zero and discard
+  // operations should not have source extents.
+  if (!IsNoSourceOperation(operation.type())) {
+    StoreExtents(src_extents, operation.mutable_src_extents());
+  }
+  // All operations have dst_extents.
   StoreExtents(dst_extents, operation.mutable_dst_extents());
 
-  // Replace operations should not have source extents.
-  if (IsAReplaceOperation(operation.type())) {
-    operation.clear_src_extents();
-    operation.clear_src_length();
-  }
-
   *out_data = std::move(data_blob);
   *out_op = operation;
-
-  return true;
-}
-
-// Runs the bsdiff or imgdiff tool in |diff_path| on two files and returns the
-// resulting delta in |out|. Returns true on success.
-bool DiffFiles(const string& diff_path,
-               const string& old_file,
-               const string& new_file,
-               brillo::Blob* out) {
-  const string kPatchFile = "delta.patchXXXXXX";
-  string patch_file_path;
-
-  TEST_AND_RETURN_FALSE(
-      utils::MakeTempFile(kPatchFile, &patch_file_path, nullptr));
-
-  vector<string> cmd;
-  cmd.push_back(diff_path);
-  cmd.push_back(old_file);
-  cmd.push_back(new_file);
-  cmd.push_back(patch_file_path);
-
-  int rc = 1;
-  string stdout;
-  TEST_AND_RETURN_FALSE(Subprocess::SynchronousExec(cmd, &rc, &stdout));
-  if (rc != 0) {
-    LOG(ERROR) << diff_path << " returned " << rc << std::endl << stdout;
-    return false;
-  }
-  TEST_AND_RETURN_FALSE(utils::ReadFile(patch_file_path, out));
-  unlink(patch_file_path.c_str());
   return true;
 }
 
@@ -823,6 +855,12 @@
           op_type == InstallOperation::REPLACE_XZ);
 }
 
+bool IsNoSourceOperation(InstallOperation_Type op_type) {
+  return (IsAReplaceOperation(op_type) ||
+          op_type == InstallOperation::ZERO ||
+          op_type == InstallOperation::DISCARD);
+}
+
 // Returns true if |op| is a no-op operation that doesn't do any useful work
 // (e.g., a move operation that copies blocks onto themselves).
 bool IsNoopOperation(const InstallOperation& op) {
diff --git a/payload_generator/delta_diff_utils.h b/payload_generator/delta_diff_utils.h
index c9fef17..dea8535 100644
--- a/payload_generator/delta_diff_utils.h
+++ b/payload_generator/delta_diff_utils.h
@@ -21,6 +21,7 @@
 #include <vector>
 
 #include <brillo/secure_blob.h>
+#include <puffin/puffdiff.h>
 
 #include "update_engine/payload_generator/annotated_operation.h"
 #include "update_engine/payload_generator/extent_ranges.h"
@@ -76,12 +77,15 @@
 // stored in |new_part| in the blocks described by |new_extents| and, if it
 // exists, the old version exists in |old_part| in the blocks described by
 // |old_extents|. The operations added to |aops| reference the data blob
-// in the |blob_file|. Returns true on success.
+// in the |blob_file|. |old_deflates| and |new_deflates| are all deflate
+// locations in |old_part| and |new_part|. Returns true on success.
 bool DeltaReadFile(std::vector<AnnotatedOperation>* aops,
                    const std::string& old_part,
                    const std::string& new_part,
                    const std::vector<Extent>& old_extents,
                    const std::vector<Extent>& new_extents,
+                   const std::vector<puffin::BitExtent>& old_deflates,
+                   const std::vector<puffin::BitExtent>& new_deflates,
                    const std::string& name,
                    ssize_t chunk_blocks,
                    const PayloadVersion& version,
@@ -93,23 +97,19 @@
 // fills in |out_op|. If there's no change in old and new files, it creates a
 // MOVE or SOURCE_COPY operation. If there is a change, the smallest of the
 // operations allowed in the given |version| (REPLACE, REPLACE_BZ, BSDIFF,
-// SOURCE_BSDIFF or IMGDIFF) wins.
-// |new_extents| must not be empty. Returns true on success.
+// SOURCE_BSDIFF, or PUFFDIFF) wins.
+// |new_extents| must not be empty. |old_deflates| and |new_deflates| are all
+// the deflate locations in |old_part| and |new_part|. Returns true on success.
 bool ReadExtentsToDiff(const std::string& old_part,
                        const std::string& new_part,
                        const std::vector<Extent>& old_extents,
                        const std::vector<Extent>& new_extents,
+                       const std::vector<puffin::BitExtent>& old_deflates,
+                       const std::vector<puffin::BitExtent>& new_deflates,
                        const PayloadVersion& version,
                        brillo::Blob* out_data,
                        InstallOperation* out_op);
 
-// Runs the bsdiff or imgdiff tool in |diff_path| on two files and returns the
-// resulting delta in |out|. Returns true on success.
-bool DiffFiles(const std::string& diff_path,
-               const std::string& old_file,
-               const std::string& new_file,
-               brillo::Blob* out);
-
 // Generates the best allowed full operation to produce |new_data|. The allowed
 // operations are based on |payload_version|. The operation blob will be stored
 // in |out_blob| and the resulting operation type in |out_type|. Returns whether
@@ -119,9 +119,12 @@
                                brillo::Blob* out_blob,
                                InstallOperation_Type* out_type);
 
-// Returns whether op_type is one of the REPLACE full operations.
+// Returns whether |op_type| is one of the REPLACE full operations.
 bool IsAReplaceOperation(InstallOperation_Type op_type);
 
+// Returns true if an operation with type |op_type| has no |src_extents|.
+bool IsNoSourceOperation(InstallOperation_Type op_type);
+
 // Returns true if |op| is a no-op operation that doesn't do any useful work
 // (e.g., a move operation that copies blocks onto themselves).
 bool IsNoopOperation(const InstallOperation& op);
diff --git a/payload_generator/delta_diff_utils_unittest.cc b/payload_generator/delta_diff_utils_unittest.cc
index 232eab7..a83cea2 100644
--- a/payload_generator/delta_diff_utils_unittest.cc
+++ b/payload_generator/delta_diff_utils_unittest.cc
@@ -131,7 +131,6 @@
                                   uint32_t minor_version) {
     BlobFileWriter blob_file(blob_fd_, &blob_size_);
     PayloadVersion version(kChromeOSMajorPayloadVersion, minor_version);
-    version.imgdiff_allowed = true;  // Assume no fingerprint mismatch.
     return diff_utils::DeltaMovedAndZeroBlocks(&aops_,
                                                old_part_.path,
                                                new_part_.path,
@@ -180,6 +179,8 @@
       new_part_.path,
       old_extents,
       new_extents,
+      {},  // old_deflates
+      {},  // new_deflates
       PayloadVersion(kChromeOSMajorPayloadVersion, kInPlaceMinorPayloadVersion),
       &data,
       &op));
@@ -193,9 +194,9 @@
   EXPECT_EQ(kBlockSize, op.src_length());
   EXPECT_EQ(1, op.dst_extents_size());
   EXPECT_EQ(kBlockSize, op.dst_length());
-  EXPECT_EQ(BlocksInExtents(op.src_extents()),
-            BlocksInExtents(op.dst_extents()));
-  EXPECT_EQ(1U, BlocksInExtents(op.dst_extents()));
+  EXPECT_EQ(utils::BlocksInExtents(op.src_extents()),
+            utils::BlocksInExtents(op.dst_extents()));
+  EXPECT_EQ(1U, utils::BlocksInExtents(op.dst_extents()));
 }
 
 TEST_F(DeltaDiffUtilsTest, MoveWithSameBlock) {
@@ -219,8 +220,8 @@
       ExtentForRange(24, 3),
       ExtentForRange(29, 1) };
 
-  uint64_t num_blocks = BlocksInExtents(old_extents);
-  EXPECT_EQ(num_blocks, BlocksInExtents(new_extents));
+  uint64_t num_blocks = utils::BlocksInExtents(old_extents);
+  EXPECT_EQ(num_blocks, utils::BlocksInExtents(new_extents));
 
   // The size of the data should match the total number of blocks. Each block
   // has a different content.
@@ -239,6 +240,8 @@
       new_part_.path,
       old_extents,
       new_extents,
+      {},  // old_deflates
+      {},  // new_deflates
       PayloadVersion(kChromeOSMajorPayloadVersion, kInPlaceMinorPayloadVersion),
       &data,
       &op));
@@ -259,7 +262,7 @@
       ExtentForRange(18, 1),
       ExtentForRange(20, 1),
       ExtentForRange(26, 1) };
-  num_blocks = BlocksInExtents(old_extents);
+  num_blocks = utils::BlocksInExtents(old_extents);
 
   EXPECT_EQ(num_blocks * kBlockSize, op.src_length());
   EXPECT_EQ(num_blocks * kBlockSize, op.dst_length());
@@ -302,6 +305,8 @@
       new_part_.path,
       old_extents,
       new_extents,
+      {},  // old_deflates
+      {},  // new_deflates
       PayloadVersion(kChromeOSMajorPayloadVersion, kInPlaceMinorPayloadVersion),
       &data,
       &op));
@@ -316,9 +321,9 @@
   EXPECT_EQ(kBlockSize, op.src_length());
   EXPECT_EQ(1, op.dst_extents_size());
   EXPECT_EQ(kBlockSize, op.dst_length());
-  EXPECT_EQ(BlocksInExtents(op.src_extents()),
-            BlocksInExtents(op.dst_extents()));
-  EXPECT_EQ(1U, BlocksInExtents(op.dst_extents()));
+  EXPECT_EQ(utils::BlocksInExtents(op.src_extents()),
+            utils::BlocksInExtents(op.dst_extents()));
+  EXPECT_EQ(1U, utils::BlocksInExtents(op.dst_extents()));
 }
 
 TEST_F(DeltaDiffUtilsTest, ReplaceSmallTest) {
@@ -350,6 +355,8 @@
         new_part_.path,
         old_extents,
         new_extents,
+        {},  // old_deflates
+        {},  // new_deflates
         PayloadVersion(kChromeOSMajorPayloadVersion,
                        kInPlaceMinorPayloadVersion),
         &data,
@@ -365,8 +372,8 @@
     EXPECT_EQ(0, op.src_extents_size());
     EXPECT_FALSE(op.has_src_length());
     EXPECT_EQ(1, op.dst_extents_size());
-    EXPECT_EQ(data_to_test.size(), op.dst_length());
-    EXPECT_EQ(1U, BlocksInExtents(op.dst_extents()));
+    EXPECT_FALSE(op.has_dst_length());
+    EXPECT_EQ(1U, utils::BlocksInExtents(op.dst_extents()));
   }
 }
 
@@ -391,6 +398,8 @@
       new_part_.path,
       old_extents,
       new_extents,
+      {},  // old_deflates
+      {},  // new_deflates
       PayloadVersion(kChromeOSMajorPayloadVersion, kSourceMinorPayloadVersion),
       &data,
       &op));
@@ -423,6 +432,8 @@
       new_part_.path,
       old_extents,
       new_extents,
+      {},  // old_deflates
+      {},  // new_deflates
       PayloadVersion(kChromeOSMajorPayloadVersion, kSourceMinorPayloadVersion),
       &data,
       &op));
@@ -623,7 +634,8 @@
       // The last range is split since the old image has zeros in part of it.
       ExtentForRange(30, 20),
   };
-  brillo::Blob zeros_data(BlocksInExtents(new_zeros) * block_size_, '\0');
+  brillo::Blob zeros_data(utils::BlocksInExtents(new_zeros) * block_size_,
+                          '\0');
   EXPECT_TRUE(WriteExtents(new_part_.path, new_zeros, block_size_, zeros_data));
 
   vector<Extent> old_zeros = vector<Extent>{ExtentForRange(43, 7)};
diff --git a/payload_generator/ext2_filesystem.cc b/payload_generator/ext2_filesystem.cc
index ee2f8c2..07ec371 100644
--- a/payload_generator/ext2_filesystem.cc
+++ b/payload_generator/ext2_filesystem.cc
@@ -17,12 +17,16 @@
 #include "update_engine/payload_generator/ext2_filesystem.h"
 
 #include <et/com_err.h>
-// TODO: Remove these pragmas when b/35721782 is fixed.
+#if defined(__clang__)
+// TODO(*): Remove these pragmas when b/35721782 is fixed.
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wmacro-redefined"
+#endif
 #include <ext2fs/ext2_io.h>
 #include <ext2fs/ext2fs.h>
+#if defined(__clang__)
 #pragma clang diagnostic pop
+#endif
 
 #include <map>
 #include <set>
@@ -344,7 +348,7 @@
     return false;
 
   brillo::Blob blob;
-  uint64_t physical_size = BlocksInExtents(extents) * filsys_->blocksize;
+  uint64_t physical_size = utils::BlocksInExtents(extents) * filsys_->blocksize;
   // Sparse holes in the settings file are not supported.
   if (EXT2_I_SIZE(&ino_data) > physical_size)
     return false;
diff --git a/payload_generator/ext2_filesystem.h b/payload_generator/ext2_filesystem.h
index 1a4e1a1..c0562d0 100644
--- a/payload_generator/ext2_filesystem.h
+++ b/payload_generator/ext2_filesystem.h
@@ -23,11 +23,15 @@
 #include <string>
 #include <vector>
 
+#if defined(__clang__)
 // TODO: Remove these pragmas when b/35721782 is fixed.
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wmacro-redefined"
+#endif
 #include <ext2fs/ext2fs.h>
+#if defined(__clang__)
 #pragma clang diagnostic pop
+#endif
 
 namespace chromeos_update_engine {
 
diff --git a/payload_generator/ext2_filesystem_unittest.cc b/payload_generator/ext2_filesystem_unittest.cc
index a3c7731..5360e6c 100644
--- a/payload_generator/ext2_filesystem_unittest.cc
+++ b/payload_generator/ext2_filesystem_unittest.cc
@@ -158,7 +158,8 @@
 
     // Small symlinks don't actually have data blocks.
     EXPECT_TRUE(map_files["/link-short_symlink"].extents.empty());
-    EXPECT_EQ(1U, BlocksInExtents(map_files["/link-long_symlink"].extents));
+    EXPECT_EQ(1U,
+              utils::BlocksInExtents(map_files["/link-long_symlink"].extents));
 
     // Hard-links report the same list of blocks.
     EXPECT_EQ(map_files["/link-hard-regular-16k"].extents,
@@ -168,14 +169,19 @@
     // The number of blocks in these files doesn't depend on the
     // block size.
     EXPECT_TRUE(map_files["/empty-file"].extents.empty());
-    EXPECT_EQ(1U, BlocksInExtents(map_files["/regular-small"].extents));
-    EXPECT_EQ(1U, BlocksInExtents(map_files["/regular-with_net_cap"].extents));
+    EXPECT_EQ(1U, utils::BlocksInExtents(map_files["/regular-small"].extents));
+    EXPECT_EQ(
+        1U, utils::BlocksInExtents(map_files["/regular-with_net_cap"].extents));
     EXPECT_TRUE(map_files["/sparse_empty-10k"].extents.empty());
     EXPECT_TRUE(map_files["/sparse_empty-2blocks"].extents.empty());
-    EXPECT_EQ(1U, BlocksInExtents(map_files["/sparse-16k-last_block"].extents));
-    EXPECT_EQ(1U,
-              BlocksInExtents(map_files["/sparse-16k-first_block"].extents));
-    EXPECT_EQ(2U, BlocksInExtents(map_files["/sparse-16k-holes"].extents));
+    EXPECT_EQ(
+        1U,
+        utils::BlocksInExtents(map_files["/sparse-16k-last_block"].extents));
+    EXPECT_EQ(
+        1U,
+        utils::BlocksInExtents(map_files["/sparse-16k-first_block"].extents));
+    EXPECT_EQ(2U,
+              utils::BlocksInExtents(map_files["/sparse-16k-holes"].extents));
   }
 }
 
diff --git a/payload_generator/extent_ranges.cc b/payload_generator/extent_ranges.cc
index 0e0cdf7..c1d3d63 100644
--- a/payload_generator/extent_ranges.cc
+++ b/payload_generator/extent_ranges.cc
@@ -23,6 +23,7 @@
 
 #include <base/logging.h>
 
+#include "update_engine/common/utils.h"
 #include "update_engine/payload_consumer/payload_constants.h"
 #include "update_engine/payload_generator/extent_utils.h"
 
@@ -250,7 +251,7 @@
     out.back().set_num_blocks(blocks_needed);
     break;
   }
-  CHECK(out_blocks == BlocksInExtents(out));
+  CHECK(out_blocks == utils::BlocksInExtents(out));
   return out;
 }
 
diff --git a/payload_generator/extent_utils.cc b/payload_generator/extent_utils.cc
index 89ccca2..47073f9 100644
--- a/payload_generator/extent_utils.cc
+++ b/payload_generator/extent_utils.cc
@@ -53,16 +53,6 @@
   extents->push_back(new_extent);
 }
 
-Extent GetElement(const vector<Extent>& collection, size_t index) {
-  return collection[index];
-}
-
-Extent GetElement(
-    const google::protobuf::RepeatedPtrField<Extent>& collection,
-    size_t index) {
-  return collection.Get(index);
-}
-
 void ExtendExtents(
     google::protobuf::RepeatedPtrField<Extent>* extents,
     const google::protobuf::RepeatedPtrField<Extent>& extents_to_add) {
diff --git a/payload_generator/extent_utils.h b/payload_generator/extent_utils.h
index 3e45264..f5fbb0e 100644
--- a/payload_generator/extent_utils.h
+++ b/payload_generator/extent_utils.h
@@ -32,31 +32,12 @@
 // into an arbitrary place in the extents.
 void AppendBlockToExtents(std::vector<Extent>* extents, uint64_t block);
 
-// Get/SetElement are intentionally overloaded so that templated functions
-// can accept either type of collection of Extents.
-Extent GetElement(const std::vector<Extent>& collection, size_t index);
-Extent GetElement(
-    const google::protobuf::RepeatedPtrField<Extent>& collection,
-    size_t index);
-
-// Return the total number of blocks in a collection (vector or
-// RepeatedPtrField) of Extents.
-template<typename T>
-uint64_t BlocksInExtents(const T& collection) {
-  uint64_t ret = 0;
-  for (size_t i = 0; i < static_cast<size_t>(collection.size()); ++i) {
-    ret += GetElement(collection, i).num_blocks();
-  }
-  return ret;
-}
-
 // Takes a collection (vector or RepeatedPtrField) of Extent and
 // returns a vector of the blocks referenced, in order.
 template<typename T>
 std::vector<uint64_t> ExpandExtents(const T& extents) {
   std::vector<uint64_t> ret;
-  for (size_t i = 0, e = static_cast<size_t>(extents.size()); i != e; ++i) {
-    const Extent extent = GetElement(extents, i);
+  for (const auto& extent : extents) {
     if (extent.start_block() == kSparseHole) {
       ret.resize(ret.size() + extent.num_blocks(), kSparseHole);
     } else {
diff --git a/payload_generator/extent_utils_unittest.cc b/payload_generator/extent_utils_unittest.cc
index d470e7b..eef4385 100644
--- a/payload_generator/extent_utils_unittest.cc
+++ b/payload_generator/extent_utils_unittest.cc
@@ -54,23 +54,23 @@
 TEST(ExtentUtilsTest, BlocksInExtentsTest) {
   {
     vector<Extent> extents;
-    EXPECT_EQ(0U, BlocksInExtents(extents));
+    EXPECT_EQ(0U, utils::BlocksInExtents(extents));
     extents.push_back(ExtentForRange(0, 1));
-    EXPECT_EQ(1U, BlocksInExtents(extents));
+    EXPECT_EQ(1U, utils::BlocksInExtents(extents));
     extents.push_back(ExtentForRange(23, 55));
-    EXPECT_EQ(56U, BlocksInExtents(extents));
+    EXPECT_EQ(56U, utils::BlocksInExtents(extents));
     extents.push_back(ExtentForRange(1, 2));
-    EXPECT_EQ(58U, BlocksInExtents(extents));
+    EXPECT_EQ(58U, utils::BlocksInExtents(extents));
   }
   {
     google::protobuf::RepeatedPtrField<Extent> extents;
-    EXPECT_EQ(0U, BlocksInExtents(extents));
+    EXPECT_EQ(0U, utils::BlocksInExtents(extents));
     *extents.Add() = ExtentForRange(0, 1);
-    EXPECT_EQ(1U, BlocksInExtents(extents));
+    EXPECT_EQ(1U, utils::BlocksInExtents(extents));
     *extents.Add() = ExtentForRange(23, 55);
-    EXPECT_EQ(56U, BlocksInExtents(extents));
+    EXPECT_EQ(56U, utils::BlocksInExtents(extents));
     *extents.Add() = ExtentForRange(1, 2);
-    EXPECT_EQ(58U, BlocksInExtents(extents));
+    EXPECT_EQ(58U, utils::BlocksInExtents(extents));
   }
 }
 
diff --git a/payload_generator/filesystem_interface.h b/payload_generator/filesystem_interface.h
index 866c46b..b1506e4 100644
--- a/payload_generator/filesystem_interface.h
+++ b/payload_generator/filesystem_interface.h
@@ -33,6 +33,7 @@
 
 #include <base/macros.h>
 #include <brillo/key_value_store.h>
+#include <puffin/utils.h>
 
 #include "update_engine/update_metadata.pb.h"
 
@@ -62,6 +63,10 @@
     // between 0 and GetBlockCount() - 1. The blocks are encoded in extents,
     // indicating the starting block, and the number of consecutive blocks.
     std::vector<Extent> extents;
+
+    // All the deflate locations in the file. These locations are not relative
+    // to the extents. They are relative to the file system itself.
+    std::vector<puffin::BitExtent> deflates;
   };
 
   virtual ~FilesystemInterface() = default;
diff --git a/payload_generator/full_update_generator_unittest.cc b/payload_generator/full_update_generator_unittest.cc
index 9e62de2..6da4d10 100644
--- a/payload_generator/full_update_generator_unittest.cc
+++ b/payload_generator/full_update_generator_unittest.cc
@@ -16,6 +16,7 @@
 
 #include "update_engine/payload_generator/full_update_generator.h"
 
+#include <memory>
 #include <string>
 #include <vector>
 
@@ -116,9 +117,9 @@
   // new_part has one chunk and a half.
   EXPECT_EQ(2U, aops.size());
   EXPECT_EQ(config_.hard_chunk_size / config_.block_size,
-            BlocksInExtents(aops[0].op.dst_extents()));
+            utils::BlocksInExtents(aops[0].op.dst_extents()));
   EXPECT_EQ((new_part.size() - config_.hard_chunk_size) / config_.block_size,
-            BlocksInExtents(aops[1].op.dst_extents()));
+            utils::BlocksInExtents(aops[1].op.dst_extents()));
 }
 
 // Test that if the image size is much smaller than the chunk size, it handles
@@ -138,7 +139,7 @@
   // new_part has less than one chunk.
   EXPECT_EQ(1U, aops.size());
   EXPECT_EQ(new_part.size() / config_.block_size,
-            BlocksInExtents(aops[0].op.dst_extents()));
+            utils::BlocksInExtents(aops[0].op.dst_extents()));
 }
 
 }  // namespace chromeos_update_engine
diff --git a/payload_generator/generate_delta_main.cc b/payload_generator/generate_delta_main.cc
index cd99a51..2729bc4 100644
--- a/payload_generator/generate_delta_main.cc
+++ b/payload_generator/generate_delta_main.cc
@@ -19,6 +19,7 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <xz.h>
 
 #include <string>
 #include <vector>
@@ -29,13 +30,14 @@
 #include <brillo/flag_helper.h>
 #include <brillo/key_value_store.h>
 
+#include "update_engine/common/fake_boot_control.h"
+#include "update_engine/common/fake_hardware.h"
 #include "update_engine/common/prefs.h"
 #include "update_engine/common/terminator.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/payload_consumer/delta_performer.h"
 #include "update_engine/payload_consumer/payload_constants.h"
 #include "update_engine/payload_generator/delta_diff_generator.h"
-#include "update_engine/payload_generator/delta_diff_utils.h"
 #include "update_engine/payload_generator/payload_generation_config.h"
 #include "update_engine/payload_generator/payload_signer.h"
 #include "update_engine/payload_generator/xz.h"
@@ -165,73 +167,84 @@
   }
 }
 
-void VerifySignedPayload(const string& in_file,
-                         const string& public_key) {
+int VerifySignedPayload(const string& in_file, const string& public_key) {
   LOG(INFO) << "Verifying signed payload.";
   LOG_IF(FATAL, in_file.empty())
       << "Must pass --in_file to verify signed payload.";
   LOG_IF(FATAL, public_key.empty())
       << "Must pass --public_key to verify signed payload.";
-  CHECK(PayloadSigner::VerifySignedPayload(in_file, public_key));
+  if (!PayloadSigner::VerifySignedPayload(in_file, public_key)) {
+    LOG(INFO) << "VerifySignedPayload failed";
+    return 1;
+  }
+
   LOG(INFO) << "Done verifying signed payload.";
+  return 0;
 }
 
 // TODO(deymo): This function is likely broken for deltas minor version 2 or
 // newer. Move this function to a new file and make the delta_performer
 // integration tests use this instead.
-void ApplyDelta(const string& in_file,
-                const string& old_kernel,
-                const string& old_rootfs,
-                const string& prefs_dir) {
+bool ApplyPayload(const string& payload_file,
+                  // Simply reuses the payload config used for payload
+                  // generation.
+                  const PayloadGenerationConfig& config) {
   LOG(INFO) << "Applying delta.";
-  LOG_IF(FATAL, old_rootfs.empty())
-      << "Must pass --old_image to apply delta.";
-  Prefs prefs;
+  FakeBootControl fake_boot_control;
+  FakeHardware fake_hardware;
+  MemoryPrefs prefs;
   InstallPlan install_plan;
-  LOG(INFO) << "Setting up preferences under: " << prefs_dir;
-  LOG_IF(ERROR, !prefs.Init(base::FilePath(prefs_dir)))
-      << "Failed to initialize preferences.";
-  // Get original checksums
-  LOG(INFO) << "Calculating original checksums";
-  ImageConfig old_image;
-  old_image.partitions.emplace_back(kLegacyPartitionNameRoot);
-  old_image.partitions.back().path = old_rootfs;
-  old_image.partitions.emplace_back(kLegacyPartitionNameKernel);
-  old_image.partitions.back().path = old_kernel;
-  CHECK(old_image.LoadImageSize());
-  for (const auto& old_part : old_image.partitions) {
-    PartitionInfo part_info;
-    CHECK(diff_utils::InitializePartitionInfo(old_part, &part_info));
-    InstallPlan::Partition part;
-    part.name = old_part.name;
-    part.source_hash.assign(part_info.hash().begin(),
-                            part_info.hash().end());
-    part.source_path = old_part.path;
-    // Apply the delta in-place to the old_part.
-    part.target_path = old_part.path;
-    install_plan.partitions.push_back(part);
+  InstallPlan::Payload payload;
+  install_plan.source_slot =
+      config.is_delta ? 0 : BootControlInterface::kInvalidSlot;
+  install_plan.target_slot = 1;
+  payload.type =
+      config.is_delta ? InstallPayloadType::kDelta : InstallPayloadType::kFull;
+
+  for (size_t i = 0; i < config.target.partitions.size(); i++) {
+    const string& part_name = config.target.partitions[i].name;
+    const string& target_path = config.target.partitions[i].path;
+    fake_boot_control.SetPartitionDevice(
+        part_name, install_plan.target_slot, target_path);
+
+    string source_path;
+    if (config.is_delta) {
+      TEST_AND_RETURN_FALSE(config.target.partitions.size() ==
+                            config.source.partitions.size());
+      source_path = config.source.partitions[i].path;
+      fake_boot_control.SetPartitionDevice(
+          part_name, install_plan.source_slot, source_path);
+    }
+
+    LOG(INFO) << "Install partition:"
+              << " source: " << source_path << " target: " << target_path;
   }
-  install_plan.payloads.resize(1);
+
   DeltaPerformer performer(&prefs,
-                           nullptr,
-                           nullptr,
+                           &fake_boot_control,
+                           &fake_hardware,
                            nullptr,
                            &install_plan,
-                           &install_plan.payloads[0]);
+                           &payload,
+                           true);  // is_interactive
+
   brillo::Blob buf(1024 * 1024);
-  int fd = open(in_file.c_str(), O_RDONLY, 0);
+  int fd = open(payload_file.c_str(), O_RDONLY, 0);
   CHECK_GE(fd, 0);
   ScopedFdCloser fd_closer(&fd);
+  xz_crc32_init();
   for (off_t offset = 0;; offset += buf.size()) {
     ssize_t bytes_read;
     CHECK(utils::PReadAll(fd, buf.data(), buf.size(), offset, &bytes_read));
     if (bytes_read == 0)
       break;
-    CHECK_EQ(performer.Write(buf.data(), bytes_read), bytes_read);
+    TEST_AND_RETURN_FALSE(performer.Write(buf.data(), bytes_read));
   }
   CHECK_EQ(performer.Close(), 0);
   DeltaPerformer::ResetUpdateProgress(&prefs, false);
-  LOG(INFO) << "Done applying delta.";
+  LOG(INFO) << "Completed applying " << (config.is_delta ? "delta" : "full")
+            << " payload.";
+  return true;
 }
 
 int ExtractProperties(const string& payload_path, const string& props_file) {
@@ -293,8 +306,6 @@
   DEFINE_string(public_key, "", "Path to public key in .pem format");
   DEFINE_int32(public_key_version, -1,
                "DEPRECATED. Key-check version # of client");
-  DEFINE_string(prefs_dir, "/tmp/update_engine_prefs",
-                "Preferences directory, used with apply_delta");
   DEFINE_string(signature_size, "",
                 "Raw signature size used for hash calculation. "
                 "You may pass in multiple sizes by colon separating them. E.g. "
@@ -324,9 +335,6 @@
   DEFINE_string(properties_file, "",
                 "If passed, dumps the payload properties of the payload passed "
                 "in --in_file and exits.");
-  DEFINE_string(zlib_fingerprint, "",
-                "The fingerprint of zlib in the source image in hash string "
-                "format, used to check imgdiff compatibility.");
   DEFINE_int64(max_timestamp,
                0,
                "The maximum timestamp of the OS allowed to apply this "
@@ -406,17 +414,11 @@
   if (!FLAGS_public_key.empty()) {
     LOG_IF(WARNING, FLAGS_public_key_version != -1)
         << "--public_key_version is deprecated and ignored.";
-    VerifySignedPayload(FLAGS_in_file, FLAGS_public_key);
-    return 0;
+    return VerifySignedPayload(FLAGS_in_file, FLAGS_public_key);
   }
   if (!FLAGS_properties_file.empty()) {
     return ExtractProperties(FLAGS_in_file, FLAGS_properties_file) ? 0 : 1;
   }
-  if (!FLAGS_in_file.empty()) {
-    ApplyDelta(FLAGS_in_file, FLAGS_old_kernel, FLAGS_old_image,
-               FLAGS_prefs_dir);
-    return 0;
-  }
 
   // A payload generation was requested. Convert the flags to a
   // PayloadGenerationConfig.
@@ -499,6 +501,10 @@
     }
   }
 
+  if (!FLAGS_in_file.empty()) {
+    return ApplyPayload(FLAGS_in_file, payload_config) ? 0 : 1;
+  }
+
   if (!FLAGS_new_postinstall_config_file.empty()) {
     LOG_IF(FATAL, FLAGS_major_version == kChromeOSMajorPayloadVersion)
         << "Postinstall config is only allowed in major version 2 or newer.";
@@ -574,21 +580,10 @@
     LOG(INFO) << "Using provided minor_version=" << FLAGS_minor_version;
   }
 
-  if (!FLAGS_zlib_fingerprint.empty()) {
-    if (utils::IsZlibCompatible(FLAGS_zlib_fingerprint)) {
-      payload_config.version.imgdiff_allowed = true;
-    } else {
-      LOG(INFO) << "IMGDIFF operation disabled due to fingerprint mismatch.";
-    }
-  }
-
   payload_config.max_timestamp = FLAGS_max_timestamp;
 
-  if (payload_config.is_delta) {
-    LOG(INFO) << "Generating delta update";
-  } else {
-    LOG(INFO) << "Generating full update";
-  }
+  LOG(INFO) << "Generating " << (payload_config.is_delta ? "delta" : "full")
+            << " update";
 
   // From this point, all the options have been parsed.
   if (!payload_config.Validate()) {
diff --git a/payload_generator/graph_utils.cc b/payload_generator/graph_utils.cc
index 2d5fb63..4829b21 100644
--- a/payload_generator/graph_utils.cc
+++ b/payload_generator/graph_utils.cc
@@ -104,9 +104,9 @@
 template<typename T>
 void DumpExtents(const T& field, int prepend_space_count) {
   string header(prepend_space_count, ' ');
-  for (int i = 0, e = field.size(); i != e; ++i) {
-    LOG(INFO) << header << "(" << GetElement(field, i).start_block() << ", "
-              << GetElement(field, i).num_blocks() << ")";
+  for (const auto& extent : field) {
+    LOG(INFO) << header << "(" << extent.start_block() << ", "
+              << extent.num_blocks() << ")";
   }
 }
 
diff --git a/payload_generator/inplace_generator.cc b/payload_generator/inplace_generator.cc
index bc140e8..b858c2b 100644
--- a/payload_generator/inplace_generator.cc
+++ b/payload_generator/inplace_generator.cc
@@ -299,8 +299,7 @@
 
 template<typename T>
 bool TempBlocksExistInExtents(const T& extents) {
-  for (int i = 0, e = extents.size(); i < e; ++i) {
-    Extent extent = GetElement(extents, i);
+  for (const auto& extent : extents) {
     uint64_t start = extent.start_block();
     uint64_t num = extent.num_blocks();
     if (start >= kTempBlockStart || (start + num) >= kTempBlockStart) {
@@ -573,6 +572,8 @@
         new_part,
         vector<Extent>(),  // old_extents
         new_extents,
+        {},  // old_deflates
+        {},  // new_deflates
         (*graph)[cut.old_dst].aop.name,
         -1,  // chunk_blocks, forces to have a single operation.
         kInPlacePayloadVersion,
diff --git a/payload_generator/mapfile_filesystem.cc b/payload_generator/mapfile_filesystem.cc
index f4f0804..5264a9c 100644
--- a/payload_generator/mapfile_filesystem.cc
+++ b/payload_generator/mapfile_filesystem.cc
@@ -21,9 +21,9 @@
 
 #include <base/files/file_util.h>
 #include <base/logging.h>
+#include <base/memory/ptr_util.h>
 #include <base/strings/string_number_conversions.h>
 #include <base/strings/string_split.h>
-#include <brillo/make_unique_ptr.h>
 
 #include "update_engine/common/utils.h"
 #include "update_engine/payload_generator/extent_ranges.h"
@@ -61,8 +61,7 @@
     return nullptr;
   }
 
-  return brillo::make_unique_ptr(
-      new MapfileFilesystem(mapfile_filename, num_blocks));
+  return base::WrapUnique(new MapfileFilesystem(mapfile_filename, num_blocks));
 }
 
 MapfileFilesystem::MapfileFilesystem(const string& mapfile_filename,
diff --git a/payload_generator/payload_file.cc b/payload_generator/payload_file.cc
index 4cb117d..f48d2a2 100644
--- a/payload_generator/payload_file.cc
+++ b/payload_generator/payload_file.cc
@@ -19,6 +19,9 @@
 #include <endian.h>
 
 #include <algorithm>
+#include <map>
+
+#include <base/strings/stringprintf.h>
 
 #include "update_engine/common/hash_calculator.h"
 #include "update_engine/payload_consumer/delta_performer.h"
@@ -320,38 +323,39 @@
 }
 
 void PayloadFile::ReportPayloadUsage(uint64_t metadata_size) const {
-  vector<DeltaObject> objects;
+  std::map<DeltaObject, int> object_counts;
   off_t total_size = 0;
 
   for (const auto& part : part_vec_) {
     for (const AnnotatedOperation& aop : part.aops) {
-      objects.push_back(DeltaObject(aop.name,
-                                    aop.op.type(),
-                                    aop.op.data_length()));
+      DeltaObject delta(aop.name, aop.op.type(), aop.op.data_length());
+      object_counts[delta]++;
       total_size += aop.op.data_length();
     }
   }
 
-  objects.push_back(DeltaObject("<manifest-metadata>",
-                                -1,
-                                metadata_size));
+  object_counts[DeltaObject("<manifest-metadata>", -1, metadata_size)] = 1;
   total_size += metadata_size;
 
-  std::sort(objects.begin(), objects.end());
-
-  static const char kFormatString[] = "%6.2f%% %10jd %-10s %s\n";
-  for (const DeltaObject& object : objects) {
-    fprintf(
-        stderr, kFormatString,
+  static const char kFormatString[] = "%6.2f%% %10jd %-13s %s %d";
+  for (const auto& object_count : object_counts) {
+    const DeltaObject& object = object_count.first;
+    LOG(INFO) << base::StringPrintf(
+        kFormatString,
         object.size * 100.0 / total_size,
         static_cast<intmax_t>(object.size),
         (object.type >= 0 ? InstallOperationTypeName(
                                 static_cast<InstallOperation_Type>(object.type))
                           : "-"),
-        object.name.c_str());
+        object.name.c_str(),
+        object_count.second);
   }
-  fprintf(stderr, kFormatString,
-          100.0, static_cast<intmax_t>(total_size), "", "<total>");
+  LOG(INFO) << base::StringPrintf(kFormatString,
+                                  100.0,
+                                  static_cast<intmax_t>(total_size),
+                                  "",
+                                  "<total>",
+                                  1);
 }
 
 }  // namespace chromeos_update_engine
diff --git a/payload_generator/payload_generation_config.cc b/payload_generator/payload_generation_config.cc
index e85d693..836b481 100644
--- a/payload_generator/payload_generation_config.cc
+++ b/payload_generator/payload_generation_config.cc
@@ -128,7 +128,7 @@
                         minor == kInPlaceMinorPayloadVersion ||
                         minor == kSourceMinorPayloadVersion ||
                         minor == kOpSrcHashMinorPayloadVersion ||
-                        minor == kImgdiffMinorPayloadVersion);
+                        minor == kPuffdiffMinorPayloadVersion);
   return true;
 }
 
@@ -151,7 +151,7 @@
       // The implementation of these operations had a bug in earlier versions
       // that prevents them from being used in any payload. We will enable
       // them for delta payloads for now.
-      return minor >= kImgdiffMinorPayloadVersion;
+      return minor >= kPuffdiffMinorPayloadVersion;
 
     // Delta operations:
     case InstallOperation::MOVE:
@@ -165,8 +165,9 @@
     case InstallOperation::SOURCE_BSDIFF:
       return minor >= kSourceMinorPayloadVersion;
 
-    case InstallOperation::IMGDIFF:
-      return minor >= kImgdiffMinorPayloadVersion && imgdiff_allowed;
+    case InstallOperation::BROTLI_BSDIFF:
+    case InstallOperation::PUFFDIFF:
+      return minor >= kPuffdiffMinorPayloadVersion;
   }
   return false;
 }
diff --git a/payload_generator/payload_generation_config.h b/payload_generator/payload_generation_config.h
index dd3242a..c553d29 100644
--- a/payload_generator/payload_generation_config.h
+++ b/payload_generator/payload_generation_config.h
@@ -137,10 +137,6 @@
 
   // The minor version of the payload.
   uint32_t minor;
-
-  // Wheter the IMGDIFF operation is allowed based on the available compressor
-  // in the delta_generator and the one supported by the target.
-  bool imgdiff_allowed = false;
 };
 
 // The PayloadGenerationConfig struct encapsulates all the configuration to
diff --git a/payload_generator/squashfs_filesystem.cc b/payload_generator/squashfs_filesystem.cc
new file mode 100644
index 0000000..c98ad12
--- /dev/null
+++ b/payload_generator/squashfs_filesystem.cc
@@ -0,0 +1,332 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/payload_generator/squashfs_filesystem.h"
+
+#include <fcntl.h>
+
+#include <algorithm>
+#include <string>
+#include <utility>
+
+#include <base/files/file_util.h>
+#include <base/logging.h>
+#include <base/strings/string_number_conversions.h>
+#include <base/strings/string_split.h>
+#include <brillo/streams/file_stream.h>
+
+#include "update_engine/common/subprocess.h"
+#include "update_engine/common/utils.h"
+#include "update_engine/payload_generator/deflate_utils.h"
+#include "update_engine/payload_generator/delta_diff_generator.h"
+#include "update_engine/payload_generator/extent_ranges.h"
+#include "update_engine/payload_generator/extent_utils.h"
+#include "update_engine/update_metadata.pb.h"
+
+using std::string;
+using std::unique_ptr;
+using std::vector;
+
+namespace chromeos_update_engine {
+
+namespace {
+
+Extent ExtentForBytes(uint64_t block_size,
+                      uint64_t start_bytes,
+                      uint64_t size_bytes) {
+  uint64_t start_block = start_bytes / block_size;
+  uint64_t end_block = (start_bytes + size_bytes + block_size - 1) / block_size;
+  return ExtentForRange(start_block, end_block - start_block);
+}
+
+// The size of the squashfs super block.
+constexpr size_t kSquashfsSuperBlockSize = 96;
+constexpr uint64_t kSquashfsCompressedBit = 1 << 24;
+constexpr uint32_t kSquashfsZlibCompression = 1;
+
+bool ReadSquashfsHeader(const brillo::Blob blob,
+                        SquashfsFilesystem::SquashfsHeader* header) {
+  if (blob.size() < kSquashfsSuperBlockSize) {
+    return false;
+  }
+
+  memcpy(&header->magic, blob.data(), 4);
+  memcpy(&header->block_size, blob.data() + 12, 4);
+  memcpy(&header->compression_type, blob.data() + 20, 2);
+  memcpy(&header->major_version, blob.data() + 28, 2);
+  return true;
+}
+
+bool CheckHeader(const SquashfsFilesystem::SquashfsHeader& header) {
+  return header.magic == 0x73717368 && header.major_version == 4;
+}
+
+bool GetFileMapContent(const string& sqfs_path, string* map) {
+  // Create a tmp file
+  string map_file;
+  TEST_AND_RETURN_FALSE(
+      utils::MakeTempFile("squashfs_file_map.XXXXXX", &map_file, nullptr));
+  ScopedPathUnlinker map_unlinker(map_file);
+
+  // Run unsquashfs to get the system file map.
+  // unsquashfs -m <map-file> <squashfs-file>
+  vector<string> cmd = {"unsquashfs", "-m", map_file, sqfs_path};
+  string stdout;
+  int exit_code;
+  if (!Subprocess::SynchronousExec(cmd, &exit_code, &stdout) ||
+      exit_code != 0) {
+    LOG(ERROR) << "Failed to run unsquashfs -m. The stdout content was: "
+               << stdout;
+    return false;
+  }
+  TEST_AND_RETURN_FALSE(utils::ReadFile(map_file, map));
+  return true;
+}
+
+}  // namespace
+
+bool SquashfsFilesystem::Init(const string& map,
+                              const string& sqfs_path,
+                              size_t size,
+                              const SquashfsHeader& header,
+                              bool extract_deflates) {
+  size_ = size;
+
+  bool is_zlib = header.compression_type == kSquashfsZlibCompression;
+  if (!is_zlib) {
+    LOG(WARNING) << "Filesystem is not Gzipped. Not filling deflates!";
+  }
+  vector<puffin::ByteExtent> zlib_blks;
+
+  // Reading files map. For the format of the file map look at the comments for
+  // |CreateFromFileMap()|.
+  auto lines = base::SplitStringPiece(map,
+                                      "\n",
+                                      base::WhitespaceHandling::KEEP_WHITESPACE,
+                                      base::SplitResult::SPLIT_WANT_NONEMPTY);
+  for (const auto& line : lines) {
+    auto splits =
+        base::SplitStringPiece(line,
+                               " \t",
+                               base::WhitespaceHandling::TRIM_WHITESPACE,
+                               base::SplitResult::SPLIT_WANT_NONEMPTY);
+    // Only filename is invalid.
+    TEST_AND_RETURN_FALSE(splits.size() > 1);
+    uint64_t start;
+    TEST_AND_RETURN_FALSE(base::StringToUint64(splits[1], &start));
+    uint64_t cur_offset = start;
+    for (size_t i = 2; i < splits.size(); ++i) {
+      uint64_t blk_size;
+      TEST_AND_RETURN_FALSE(base::StringToUint64(splits[i], &blk_size));
+      // TODO(ahassani): For puffin push it into a proper list if uncompressed.
+      auto new_blk_size = blk_size & ~kSquashfsCompressedBit;
+      TEST_AND_RETURN_FALSE(new_blk_size <= header.block_size);
+      if (new_blk_size > 0 && !(blk_size & kSquashfsCompressedBit)) {
+        // Compressed block
+        if (is_zlib && extract_deflates) {
+          zlib_blks.emplace_back(cur_offset, new_blk_size);
+        }
+      }
+      cur_offset += new_blk_size;
+    }
+
+    // If size is zero do not add the file.
+    if (cur_offset - start > 0) {
+      File file;
+      file.name = splits[0].as_string();
+      file.extents = {ExtentForBytes(kBlockSize, start, cur_offset - start)};
+      files_.emplace_back(file);
+    }
+  }
+
+  // Sort all files by their offset in the squashfs.
+  std::sort(files_.begin(), files_.end(), [](const File& a, const File& b) {
+    return a.extents[0].start_block() < b.extents[0].start_block();
+  });
+  // If there is any overlap between two consecutive extents, remove them. Here
+  // we are assuming all files have exactly one extent. If this assumption
+  // changes then this implementation needs to change too.
+  for (auto first = files_.begin(), second = first + 1;
+       first != files_.end() && second != files_.end();
+       second = first + 1) {
+    auto first_begin = first->extents[0].start_block();
+    auto first_end = first_begin + first->extents[0].num_blocks();
+    auto second_begin = second->extents[0].start_block();
+    auto second_end = second_begin + second->extents[0].num_blocks();
+    // Remove the first file if the size is zero.
+    if (first_end == first_begin) {
+      first = files_.erase(first);
+    } else if (first_end > second_begin) {  // We found a collision.
+      if (second_end <= first_end) {
+        // Second file is inside the first file, remove the second file.
+        second = files_.erase(second);
+      } else if (first_begin == second_begin) {
+        // First file is inside the second file, remove the first file.
+        first = files_.erase(first);
+      } else {
+        // Remove overlapping extents from the first file.
+        first->extents[0].set_num_blocks(second_begin - first_begin);
+        ++first;
+      }
+    } else {
+      ++first;
+    }
+  }
+
+  // Find all the metadata including superblock and add them to the list of
+  // files.
+  ExtentRanges file_extents;
+  for (const auto& file : files_) {
+    file_extents.AddExtents(file.extents);
+  }
+  vector<Extent> full = {
+      ExtentForRange(0, (size_ + kBlockSize - 1) / kBlockSize)};
+  auto metadata_extents = FilterExtentRanges(full, file_extents);
+  // For now there should be at most two extents. One for superblock and one for
+  // metadata at the end. Just create appropriate files with <metadata-i> name.
+  // We can add all these extents as one metadata too, but that violates the
+  // contiguous write optimization.
+  for (size_t i = 0; i < metadata_extents.size(); i++) {
+    File file;
+    file.name = "<metadata-" + std::to_string(i) + ">";
+    file.extents = {metadata_extents[i]};
+    files_.emplace_back(file);
+  }
+
+  // Do one last sort before returning.
+  std::sort(files_.begin(), files_.end(), [](const File& a, const File& b) {
+    return a.extents[0].start_block() < b.extents[0].start_block();
+  });
+
+  if (is_zlib && extract_deflates) {
+    // If it is infact gzipped, then the sqfs_path should be valid to read its
+    // content.
+    TEST_AND_RETURN_FALSE(!sqfs_path.empty());
+    if (zlib_blks.empty()) {
+      return true;
+    }
+
+    // Sort zlib blocks.
+    std::sort(zlib_blks.begin(),
+              zlib_blks.end(),
+              [](const puffin::ByteExtent& a, const puffin::ByteExtent& b) {
+                return a.offset < b.offset;
+              });
+
+    // Sanity check. Make sure zlib blocks are not overlapping.
+    auto result = std::adjacent_find(
+        zlib_blks.begin(),
+        zlib_blks.end(),
+        [](const puffin::ByteExtent& a, const puffin::ByteExtent& b) {
+          return (a.offset + a.length) > b.offset;
+        });
+    TEST_AND_RETURN_FALSE(result == zlib_blks.end());
+
+    vector<puffin::BitExtent> deflates;
+    TEST_AND_RETURN_FALSE(
+        puffin::LocateDeflatesInZlibBlocks(sqfs_path, zlib_blks, &deflates));
+
+    // Add deflates for each file.
+    for (auto& file : files_) {
+      file.deflates = deflate_utils::FindDeflates(file.extents, deflates);
+    }
+  }
+  return true;
+}
+
+unique_ptr<SquashfsFilesystem> SquashfsFilesystem::CreateFromFile(
+    const string& sqfs_path, bool extract_deflates) {
+  if (sqfs_path.empty())
+    return nullptr;
+
+  brillo::StreamPtr sqfs_file =
+      brillo::FileStream::Open(base::FilePath(sqfs_path),
+                               brillo::Stream::AccessMode::READ,
+                               brillo::FileStream::Disposition::OPEN_EXISTING,
+                               nullptr);
+  if (!sqfs_file) {
+    LOG(ERROR) << "Unable to open " << sqfs_path << " for reading.";
+    return nullptr;
+  }
+
+  SquashfsHeader header;
+  brillo::Blob blob(kSquashfsSuperBlockSize);
+  if (!sqfs_file->ReadAllBlocking(blob.data(), blob.size(), nullptr)) {
+    LOG(ERROR) << "Unable to read from file: " << sqfs_path;
+    return nullptr;
+  }
+  if (!ReadSquashfsHeader(blob, &header) || !CheckHeader(header)) {
+    // This is not necessary an error.
+    return nullptr;
+  }
+
+  // Read the map file.
+  string filemap;
+  if (!GetFileMapContent(sqfs_path, &filemap)) {
+    LOG(ERROR) << "Failed to produce squashfs map file: " << sqfs_path;
+    return nullptr;
+  }
+
+  unique_ptr<SquashfsFilesystem> sqfs(new SquashfsFilesystem());
+  if (!sqfs->Init(
+          filemap, sqfs_path, sqfs_file->GetSize(), header, extract_deflates)) {
+    LOG(ERROR) << "Failed to initialized the Squashfs file system";
+    return nullptr;
+  }
+
+  return sqfs;
+}
+
+unique_ptr<SquashfsFilesystem> SquashfsFilesystem::CreateFromFileMap(
+    const string& filemap, size_t size, const SquashfsHeader& header) {
+  if (!CheckHeader(header)) {
+    LOG(ERROR) << "Invalid Squashfs super block!";
+    return nullptr;
+  }
+
+  unique_ptr<SquashfsFilesystem> sqfs(new SquashfsFilesystem());
+  if (!sqfs->Init(filemap, "", size, header, false)) {
+    LOG(ERROR) << "Failed to initialize the Squashfs file system using filemap";
+    return nullptr;
+  }
+  // TODO(ahassani): Add a function that initializes the puffin related extents.
+  return sqfs;
+}
+
+size_t SquashfsFilesystem::GetBlockSize() const {
+  return kBlockSize;
+}
+
+size_t SquashfsFilesystem::GetBlockCount() const {
+  return size_ / kBlockSize;
+}
+
+bool SquashfsFilesystem::GetFiles(vector<File>* files) const {
+  files->insert(files->end(), files_.begin(), files_.end());
+  return true;
+}
+
+bool SquashfsFilesystem::LoadSettings(brillo::KeyValueStore* store) const {
+  // Settings not supported in squashfs.
+  LOG(ERROR) << "squashfs doesn't support LoadSettings().";
+  return false;
+}
+
+bool SquashfsFilesystem::IsSquashfsImage(const brillo::Blob& blob) {
+  SquashfsHeader header;
+  return ReadSquashfsHeader(blob, &header) && CheckHeader(header);
+}
+}  // namespace chromeos_update_engine
diff --git a/payload_generator/squashfs_filesystem.h b/payload_generator/squashfs_filesystem.h
new file mode 100644
index 0000000..b79f8c7
--- /dev/null
+++ b/payload_generator/squashfs_filesystem.h
@@ -0,0 +1,120 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+// This class implements a FilesystemInterface, which lets the caller obtain
+// basic information about what files are in the filesystem and where are they
+// located in the disk, but not full access to the uncompressed contents of
+// these files. This class uses the definitions found in
+// fs/squashfs/squashfs_fs.h in the kernel header tree. This class supports
+// squashfs version 4 in little-endian format only.
+
+#ifndef UPDATE_ENGINE_PAYLOAD_GENERATOR_SQUASHFS_FILESYSTEM_H_
+#define UPDATE_ENGINE_PAYLOAD_GENERATOR_SQUASHFS_FILESYSTEM_H_
+
+#include <memory>
+#include <string>
+#include <vector>
+
+#include <brillo/secure_blob.h>
+
+#include "update_engine/payload_consumer/file_descriptor.h"
+#include "update_engine/payload_generator/extent_utils.h"
+#include "update_engine/payload_generator/filesystem_interface.h"
+
+namespace chromeos_update_engine {
+
+class SquashfsFilesystem : public FilesystemInterface {
+ public:
+  // From an squashfs image we need: (offset, bytes)
+  // - magic: (0, 4)
+  //   * Acceptable value is: 0x73717368
+  // - block size: (12, 4)
+  // - compression type: (20, 2)
+  //   * 1 is for zlib, gzip
+  // - major number: (28, 2)
+  //   * We only support version 4 for now.
+  struct SquashfsHeader {
+    uint32_t magic;
+    uint32_t block_size;
+    uint16_t compression_type;
+    uint16_t major_version;
+  };
+
+  ~SquashfsFilesystem() override = default;
+
+  // Creates the file system from the Squashfs file itself. If
+  // |extract_deflates| is true, it will process files to find location of all
+  // deflate streams.
+  static std::unique_ptr<SquashfsFilesystem> CreateFromFile(
+      const std::string& sqfs_path, bool extract_deflates);
+
+  // Creates the file system from a file map |filemap| which is a multi-line
+  // string with each line with the following format:
+  //
+  // file_path start_byte compressed_size_1 ... compressed_size_2
+  //
+  // file_path: The name of the file inside the Squashfs File.
+  // start_byte: The byte address of the start of the file.
+  // compressed_size_i: The compressed size of the ith block of the file.
+  //
+  // The 25th bit of compressed_size_i is set if the block is uncompressed.
+  // |size| is the size of the Squashfs image.
+  static std::unique_ptr<SquashfsFilesystem> CreateFromFileMap(
+      const std::string& filemap, size_t size, const SquashfsHeader& header);
+
+  // FilesystemInterface overrides.
+  size_t GetBlockSize() const override;
+  size_t GetBlockCount() const override;
+
+  // Returns one FilesystemInterface::File for every file (that is not added to
+  // fragments) in the squashfs image.
+  //
+  // It also returns the following metadata files:
+  //  <fragment-i>: The ith fragment in the Sqauashfs file.
+  //  <metadata-i>: The part of the file system that does not belong to any
+  //                file. Normally, there is only two: one for superblock and
+  //                one for the metadata at the end.
+  bool GetFiles(std::vector<File>* files) const override;
+
+  // Squashfs image does not support this yet.
+  bool LoadSettings(brillo::KeyValueStore* store) const override;
+
+  // Returns true if the first few bytes of a file indicates a valid Squashfs
+  // image. The size of the |blob| should be at least
+  // sizeof(SquashfsHeader) or for now 96 bytes.
+  static bool IsSquashfsImage(const brillo::Blob& blob);
+
+ private:
+  SquashfsFilesystem() = default;
+
+  // Initialize and populates the files in the file system.
+  bool Init(const std::string& map,
+            const std::string& sqfs_path,
+            size_t size,
+            const SquashfsHeader& header,
+            bool extract_deflates);
+
+  // The size of the image in bytes.
+  size_t size_;
+
+  // All the files in the filesystem.
+  std::vector<File> files_;
+
+  DISALLOW_COPY_AND_ASSIGN(SquashfsFilesystem);
+};
+
+}  // namespace chromeos_update_engine
+#endif  // UPDATE_ENGINE_PAYLOAD_GENERATOR_SQUASHFS_FILESYSTEM_H_
diff --git a/payload_generator/squashfs_filesystem_unittest.cc b/payload_generator/squashfs_filesystem_unittest.cc
new file mode 100644
index 0000000..29fcf1c
--- /dev/null
+++ b/payload_generator/squashfs_filesystem_unittest.cc
@@ -0,0 +1,318 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/payload_generator/squashfs_filesystem.h"
+
+#include <unistd.h>
+
+#include <algorithm>
+#include <map>
+#include <set>
+#include <string>
+#include <vector>
+
+#include <base/format_macros.h>
+#include <base/logging.h>
+#include <base/strings/string_number_conversions.h>
+#include <base/strings/string_util.h>
+#include <base/strings/stringprintf.h>
+#include <gtest/gtest.h>
+
+#include "update_engine/common/test_utils.h"
+#include "update_engine/common/utils.h"
+#include "update_engine/payload_generator/extent_utils.h"
+
+namespace chromeos_update_engine {
+
+using std::map;
+using std::set;
+using std::string;
+using std::unique_ptr;
+using std::vector;
+
+using test_utils::GetBuildArtifactsPath;
+
+namespace {
+
+constexpr uint64_t kTestBlockSize = 4096;
+constexpr uint64_t kTestSqfsBlockSize = 1 << 15;
+
+// Checks that all the blocks in |extents| are in the range [0, total_blocks).
+void ExpectBlocksInRange(const vector<Extent>& extents, uint64_t total_blocks) {
+  for (const Extent& extent : extents) {
+    EXPECT_LE(0U, extent.start_block());
+    EXPECT_LE(extent.start_block() + extent.num_blocks(), total_blocks);
+  }
+}
+
+SquashfsFilesystem::SquashfsHeader GetSimpleHeader() {
+  // These properties are enough for now. Add more as needed.
+  return {
+      .magic = 0x73717368,
+      .block_size = kTestSqfsBlockSize,
+      .compression_type = 1,  // For gzip.
+      .major_version = 4,
+  };
+}
+
+}  // namespace
+
+class SquashfsFilesystemTest : public ::testing::Test {
+ public:
+  void CheckSquashfs(const unique_ptr<SquashfsFilesystem>& fs) {
+    ASSERT_TRUE(fs);
+    EXPECT_EQ(kTestBlockSize, fs->GetBlockSize());
+
+    vector<FilesystemInterface::File> files;
+    ASSERT_TRUE(fs->GetFiles(&files));
+
+    map<string, FilesystemInterface::File> map_files;
+    for (const auto& file : files) {
+      EXPECT_EQ(map_files.end(), map_files.find(file.name))
+          << "File " << file.name << " repeated in the list.";
+      map_files[file.name] = file;
+      ExpectBlocksInRange(file.extents, fs->GetBlockCount());
+    }
+
+    // Checking the sortness.
+    EXPECT_TRUE(std::is_sorted(files.begin(),
+                               files.end(),
+                               [](const FilesystemInterface::File& a,
+                                  const FilesystemInterface::File& b) {
+                                 return a.extents[0].start_block() <
+                                        b.extents[0].start_block();
+                               }));
+
+    auto overlap_check = [](const FilesystemInterface::File& a,
+                            const FilesystemInterface::File& b) {
+      // Return true if overlapping.
+      return a.extents[0].start_block() + a.extents[0].num_blocks() >
+             b.extents[0].start_block();
+    };
+    // Check files are not overlapping.
+    EXPECT_EQ(std::adjacent_find(files.begin(), files.end(), overlap_check),
+              files.end());
+  }
+};
+
+// CreateFromFile() depends on unsquashfs -m, which only exists in Chrome OS.
+#ifdef __CHROMEOS__
+TEST_F(SquashfsFilesystemTest, EmptyFilesystemTest) {
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFile(
+      GetBuildArtifactsPath("gen/disk_sqfs_empty.img"), true);
+  CheckSquashfs(fs);
+
+  // Even an empty squashfs filesystem is rounded up to 4K.
+  EXPECT_EQ(4096 / kTestBlockSize, fs->GetBlockCount());
+
+  vector<FilesystemInterface::File> files;
+  ASSERT_TRUE(fs->GetFiles(&files));
+  ASSERT_EQ(files.size(), 1u);
+
+  FilesystemInterface::File file;
+  file.name = "<metadata-0>";
+  file.extents.emplace_back();
+  file.extents[0].set_start_block(0);
+  file.extents[0].set_num_blocks(1);
+  EXPECT_EQ(files[0].name, file.name);
+  EXPECT_EQ(files[0].extents, file.extents);
+}
+
+TEST_F(SquashfsFilesystemTest, DefaultFilesystemTest) {
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFile(
+      GetBuildArtifactsPath("gen/disk_sqfs_default.img"), true);
+  CheckSquashfs(fs);
+
+  vector<FilesystemInterface::File> files;
+  ASSERT_TRUE(fs->GetFiles(&files));
+  ASSERT_EQ(files.size(), 1u);
+
+  FilesystemInterface::File file;
+  file.name = "<fragment-0>";
+  file.extents.emplace_back();
+  file.extents[0].set_start_block(0);
+  file.extents[0].set_num_blocks(1);
+  EXPECT_EQ(files[0].name, file.name);
+  EXPECT_EQ(files[0].extents, file.extents);
+}
+#endif  // __CHROMEOS__
+
+TEST_F(SquashfsFilesystemTest, SimpleFileMapTest) {
+  string filemap = R"(dir1/file1 96 4000
+                      dir1/file2 4096 100)";
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFileMap(
+      filemap, kTestBlockSize * 2, GetSimpleHeader());
+  CheckSquashfs(fs);
+
+  vector<FilesystemInterface::File> files;
+  ASSERT_TRUE(fs->GetFiles(&files));
+  EXPECT_EQ(files.size(), 2u);
+}
+
+TEST_F(SquashfsFilesystemTest, FileMapZeroSizeFileTest) {
+  // The second file's size is zero.
+  string filemap = R"(dir1/file1 96 4000
+                      dir1/file2 4096
+                      dir1/file3 4096 100)";
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFileMap(
+      filemap, kTestBlockSize * 2, GetSimpleHeader());
+  CheckSquashfs(fs);
+
+  vector<FilesystemInterface::File> files;
+  ASSERT_TRUE(fs->GetFiles(&files));
+  // The second and third files are removed. The file with size zero is removed.
+  EXPECT_EQ(files.size(), 2u);
+}
+
+// Testing the compressed bit.
+TEST_F(SquashfsFilesystemTest, CompressedBitTest) {
+  string filemap = "dir1/file1 0 " + std::to_string(4000 | (1 << 24)) + "\n";
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFileMap(
+      filemap, kTestBlockSize, GetSimpleHeader());
+  CheckSquashfs(fs);
+
+  vector<FilesystemInterface::File> files;
+  ASSERT_TRUE(fs->GetFiles(&files));
+  ASSERT_EQ(files.size(), 1u);
+  EXPECT_EQ(files[0].extents[0].num_blocks(), 1u);
+}
+
+// Test overlap.
+TEST_F(SquashfsFilesystemTest, OverlapingFiles1Test) {
+  string filemap = R"(file1 0 6000
+                      file2 5000 5000)";
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFileMap(
+      filemap, kTestBlockSize * 3, GetSimpleHeader());
+  CheckSquashfs(fs);
+
+  vector<FilesystemInterface::File> files;
+  ASSERT_TRUE(fs->GetFiles(&files));
+  ASSERT_EQ(files.size(), 2u);
+  EXPECT_EQ(files[0].extents[0].num_blocks(), 1u);
+  EXPECT_EQ(files[1].extents[0].num_blocks(), 2u);
+}
+
+// Test overlap, first inside second.
+TEST_F(SquashfsFilesystemTest, OverlapingFiles2Test) {
+  string filemap = R"(file1 0 4000
+                      file2 0 6000)";
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFileMap(
+      filemap, kTestBlockSize * 2, GetSimpleHeader());
+  CheckSquashfs(fs);
+
+  vector<FilesystemInterface::File> files;
+  ASSERT_TRUE(fs->GetFiles(&files));
+  ASSERT_EQ(files.size(), 1u);
+  EXPECT_EQ(files[0].name, "file2");
+  EXPECT_EQ(files[0].extents[0].num_blocks(), 2u);
+}
+
+// Test overlap, second inside first.
+TEST_F(SquashfsFilesystemTest, OverlapingFiles3Test) {
+  string filemap = R"(file1 0 8000
+                      file2 100 100)";
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFileMap(
+      filemap, kTestBlockSize * 2, GetSimpleHeader());
+  CheckSquashfs(fs);
+
+  vector<FilesystemInterface::File> files;
+  ASSERT_TRUE(fs->GetFiles(&files));
+  ASSERT_EQ(files.size(), 1u);
+  EXPECT_EQ(files[0].name, "file1");
+  EXPECT_EQ(files[0].extents[0].num_blocks(), 2u);
+}
+
+// Fail a line with only one argument.
+TEST_F(SquashfsFilesystemTest, FailOnlyFileNameTest) {
+  string filemap = "dir1/file1\n";
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFileMap(
+      filemap, kTestBlockSize, GetSimpleHeader());
+  EXPECT_FALSE(fs);
+}
+
+// Fail a line with space separated filen name
+TEST_F(SquashfsFilesystemTest, FailSpaceInFileNameTest) {
+  string filemap = "dir1 file1 0 10\n";
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFileMap(
+      filemap, kTestBlockSize, GetSimpleHeader());
+  EXPECT_FALSE(fs);
+}
+
+// Fail empty line
+TEST_F(SquashfsFilesystemTest, FailEmptyLineTest) {
+  // The second file's size is zero.
+  string filemap = R"(
+  /t
+                      dir1/file3 4096 100)";
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFileMap(
+      filemap, kTestBlockSize * 2, GetSimpleHeader());
+  EXPECT_FALSE(fs);
+}
+
+// Fail on bad magic or major
+TEST_F(SquashfsFilesystemTest, FailBadMagicOrMajorTest) {
+  string filemap = "dir1/file1 0 10\n";
+  auto header = GetSimpleHeader();
+  header.magic = 1;
+  EXPECT_FALSE(
+      SquashfsFilesystem::CreateFromFileMap(filemap, kTestBlockSize, header));
+
+  header = GetSimpleHeader();
+  header.major_version = 3;
+  EXPECT_FALSE(
+      SquashfsFilesystem::CreateFromFileMap(filemap, kTestBlockSize, header));
+}
+
+// Fail size with larger than block_size
+TEST_F(SquashfsFilesystemTest, FailLargerThanBlockSizeTest) {
+  string filemap = "file1 0 " + std::to_string(kTestSqfsBlockSize + 1) + "\n";
+  unique_ptr<SquashfsFilesystem> fs = SquashfsFilesystem::CreateFromFileMap(
+      filemap, kTestBlockSize, GetSimpleHeader());
+  EXPECT_FALSE(fs);
+}
+
+// Test is squashfs image.
+TEST_F(SquashfsFilesystemTest, IsSquashfsImageTest) {
+  // Some sample from a recent squashfs file.
+  brillo::Blob super_block = {
+      0x68, 0x73, 0x71, 0x73, 0x59, 0x05, 0x00, 0x00, 0x09, 0x3a, 0x89, 0x58,
+      0x00, 0x00, 0x02, 0x00, 0x9a, 0x00, 0x00, 0x00, 0x01, 0x00, 0x11, 0x00,
+      0xc0, 0x00, 0x06, 0x00, 0x04, 0x00, 0x00, 0x00, 0x89, 0x18, 0xf7, 0x7c,
+      0x00, 0x00, 0x00, 0x00, 0x2e, 0x33, 0xcd, 0x16, 0x00, 0x00, 0x00, 0x00,
+      0x3a, 0x30, 0xcd, 0x16, 0x00, 0x00, 0x00, 0x00, 0x16, 0x33, 0xcd, 0x16,
+      0x00, 0x00, 0x00, 0x00, 0x07, 0x62, 0xcc, 0x16, 0x00, 0x00, 0x00, 0x00,
+      0x77, 0xe6, 0xcc, 0x16, 0x00, 0x00, 0x00, 0x00, 0x1a, 0x25, 0xcd, 0x16,
+      0x00, 0x00, 0x00, 0x00, 0x10, 0x30, 0xcd, 0x16, 0x00, 0x00, 0x00, 0x00};
+
+  EXPECT_TRUE(SquashfsFilesystem::IsSquashfsImage(super_block));
+
+  // Bad magic
+  auto bad_super_block = super_block;
+  bad_super_block[1] = 0x02;
+  EXPECT_FALSE(SquashfsFilesystem::IsSquashfsImage(bad_super_block));
+
+  // Bad major
+  bad_super_block = super_block;
+  bad_super_block[28] = 0x03;
+  EXPECT_FALSE(SquashfsFilesystem::IsSquashfsImage(bad_super_block));
+
+  // Small size;
+  bad_super_block = super_block;
+  bad_super_block.resize(10);
+  EXPECT_FALSE(SquashfsFilesystem::IsSquashfsImage(bad_super_block));
+}
+
+}  // namespace chromeos_update_engine
diff --git a/payload_generator/zip_unittest.cc b/payload_generator/zip_unittest.cc
index 54adfcb..c750eb7 100644
--- a/payload_generator/zip_unittest.cc
+++ b/payload_generator/zip_unittest.cc
@@ -17,10 +17,10 @@
 #include <string.h>
 #include <unistd.h>
 
+#include <memory>
 #include <string>
 #include <vector>
 
-#include <brillo/make_unique_ptr.h>
 #include <gtest/gtest.h>
 
 #include "update_engine/common/test_utils.h"
@@ -31,6 +31,7 @@
 #include "update_engine/payload_generator/xz.h"
 
 using chromeos_update_engine::test_utils::kRandomString;
+using google::protobuf::RepeatedPtrField;
 using std::string;
 using std::vector;
 
@@ -50,7 +51,7 @@
   ~MemoryExtentWriter() override = default;
 
   bool Init(FileDescriptorPtr fd,
-            const vector<Extent>& extents,
+            const RepeatedPtrField<Extent>& extents,
             uint32_t block_size) override {
     return true;
   }
@@ -70,7 +71,7 @@
 template <typename W>
 bool DecompressWithWriter(const brillo::Blob& in, brillo::Blob* out) {
   std::unique_ptr<ExtentWriter> writer(
-      new W(brillo::make_unique_ptr(new MemoryExtentWriter(out))));
+      new W(std::make_unique<MemoryExtentWriter>(out)));
   // Init() parameters are ignored by the testing MemoryExtentWriter.
   bool ok = writer->Init(nullptr, {}, 1);
   ok = writer->Write(in.data(), in.size()) && ok;
diff --git a/payload_state.cc b/payload_state.cc
index 96181ea..4992606 100644
--- a/payload_state.cc
+++ b/payload_state.cc
@@ -32,6 +32,7 @@
 #include "update_engine/common/prefs.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/connection_manager_interface.h"
+#include "update_engine/metrics_reporter_interface.h"
 #include "update_engine/metrics_utils.h"
 #include "update_engine/omaha_request_params.h"
 #include "update_engine/payload_consumer/install_plan.h"
@@ -44,6 +45,8 @@
 
 namespace chromeos_update_engine {
 
+using metrics_utils::GetPersistedValue;
+
 const TimeDelta PayloadState::kDurationSlack = TimeDelta::FromSeconds(600);
 
 // We want to upperbound backoffs to 16 days
@@ -235,8 +238,8 @@
       break;
 
     case AttemptType::kRollback:
-      metrics::ReportRollbackMetrics(system_state_,
-                                     metrics::RollbackResult::kSuccess);
+      system_state_->metrics_reporter()->ReportRollbackMetrics(
+          metrics::RollbackResult::kSuccess);
       break;
   }
   attempt_error_code_ = ErrorCode::kSuccess;
@@ -246,7 +249,7 @@
   SetNumResponsesSeen(0);
   SetPayloadIndex(0);
 
-  CreateSystemUpdatedMarkerFile();
+  metrics_utils::SetSystemUpdatedMarker(system_state_->clock(), prefs_);
 }
 
 void PayloadState::UpdateFailed(ErrorCode error) {
@@ -270,8 +273,8 @@
       break;
 
     case AttemptType::kRollback:
-      metrics::ReportRollbackMetrics(system_state_,
-                                     metrics::RollbackResult::kFailed);
+      system_state_->metrics_reporter()->ReportRollbackMetrics(
+          metrics::RollbackResult::kFailed);
       break;
   }
 
@@ -355,6 +358,7 @@
     case ErrorCode::kOmahaRequestXMLHasEntityDecl:
     case ErrorCode::kFilesystemVerifierError:
     case ErrorCode::kUserCanceled:
+    case ErrorCode::kUpdatedButNotActive:
       LOG(INFO) << "Not incrementing URL index or failure count for this error";
       break;
 
@@ -631,24 +635,28 @@
     case metrics::AttemptResult::kPostInstallFailed:
     case metrics::AttemptResult::kAbnormalTermination:
     case metrics::AttemptResult::kUpdateCanceled:
+    case metrics::AttemptResult::kUpdateSucceededNotActive:
     case metrics::AttemptResult::kNumConstants:
     case metrics::AttemptResult::kUnset:
       break;
   }
 
-  metrics::ReportUpdateAttemptMetrics(system_state_,
-                                      attempt_number,
-                                      payload_type,
-                                      duration,
-                                      duration_uptime,
-                                      payload_size,
-                                      payload_bytes_downloaded,
-                                      payload_download_speed_bps,
-                                      download_source,
-                                      attempt_result,
-                                      internal_error_code,
-                                      payload_download_error_code,
-                                      attempt_connection_type_);
+  system_state_->metrics_reporter()->ReportUpdateAttemptMetrics(
+      system_state_,
+      attempt_number,
+      payload_type,
+      duration,
+      duration_uptime,
+      payload_size,
+      attempt_result,
+      internal_error_code);
+
+  system_state_->metrics_reporter()->ReportUpdateAttemptDownloadMetrics(
+      payload_bytes_downloaded,
+      payload_download_speed_bps,
+      download_source,
+      payload_download_error_code,
+      attempt_connection_type_);
 }
 
 void PayloadState::PersistAttemptMetrics() {
@@ -673,7 +681,8 @@
   if (!attempt_in_progress)
     return;
 
-  metrics::ReportAbnormallyTerminatedUpdateAttemptMetrics(system_state_);
+  system_state_->metrics_reporter()
+      ->ReportAbnormallyTerminatedUpdateAttemptMetrics();
 
   ClearPersistedAttemptMetrics();
 }
@@ -735,16 +744,16 @@
 
   int updates_abandoned_count = num_responses_seen_ - 1;
 
-  metrics::ReportSuccessfulUpdateMetrics(system_state_,
-                                         attempt_count,
-                                         updates_abandoned_count,
-                                         payload_type,
-                                         payload_size,
-                                         total_bytes_by_source,
-                                         download_overhead_percentage,
-                                         duration,
-                                         reboot_count,
-                                         url_switch_count);
+  system_state_->metrics_reporter()->ReportSuccessfulUpdateMetrics(
+      attempt_count,
+      updates_abandoned_count,
+      payload_type,
+      payload_size,
+      total_bytes_by_source,
+      download_overhead_percentage,
+      duration,
+      reboot_count,
+      url_switch_count);
 }
 
 void PayloadState::UpdateNumReboots() {
@@ -758,11 +767,8 @@
 }
 
 void PayloadState::SetNumReboots(uint32_t num_reboots) {
-  CHECK(prefs_);
   num_reboots_ = num_reboots;
-  prefs_->SetInt64(kPrefsNumReboots, num_reboots);
-  LOG(INFO) << "Number of Reboots during current update attempt = "
-            << num_reboots_;
+  metrics_utils::SetNumReboots(num_reboots, prefs_);
 }
 
 void PayloadState::ResetPersistedState() {
@@ -799,24 +805,6 @@
   }
 }
 
-int64_t PayloadState::GetPersistedValue(const string& key) {
-  CHECK(prefs_);
-  if (!prefs_->Exists(key))
-    return 0;
-
-  int64_t stored_value;
-  if (!prefs_->GetInt64(key, &stored_value))
-    return 0;
-
-  if (stored_value < 0) {
-    LOG(ERROR) << key << ": Invalid value (" << stored_value
-               << ") in persisted state. Defaulting to 0";
-    return 0;
-  }
-
-  return stored_value;
-}
-
 string PayloadState::CalculateResponseSignature() {
   string response_sign;
   for (size_t i = 0; i < response_.packages.size(); i++) {
@@ -867,19 +855,18 @@
 }
 
 void PayloadState::LoadPayloadAttemptNumber() {
-  SetPayloadAttemptNumber(GetPersistedValue(kPrefsPayloadAttemptNumber));
+  SetPayloadAttemptNumber(
+      GetPersistedValue(kPrefsPayloadAttemptNumber, prefs_));
 }
 
 void PayloadState::LoadFullPayloadAttemptNumber() {
-  SetFullPayloadAttemptNumber(GetPersistedValue(
-      kPrefsFullPayloadAttemptNumber));
+  SetFullPayloadAttemptNumber(
+      GetPersistedValue(kPrefsFullPayloadAttemptNumber, prefs_));
 }
 
 void PayloadState::SetPayloadAttemptNumber(int payload_attempt_number) {
-  CHECK(prefs_);
   payload_attempt_number_ = payload_attempt_number;
-  LOG(INFO) << "Payload Attempt Number = " << payload_attempt_number_;
-  prefs_->SetInt64(kPrefsPayloadAttemptNumber, payload_attempt_number_);
+  metrics_utils::SetPayloadAttemptNumber(payload_attempt_number, prefs_);
 }
 
 void PayloadState::SetFullPayloadAttemptNumber(
@@ -906,7 +893,7 @@
 }
 
 void PayloadState::LoadUrlIndex() {
-  SetUrlIndex(GetPersistedValue(kPrefsCurrentUrlIndex));
+  SetUrlIndex(GetPersistedValue(kPrefsCurrentUrlIndex, prefs_));
 }
 
 void PayloadState::SetUrlIndex(uint32_t url_index) {
@@ -921,8 +908,8 @@
 }
 
 void PayloadState::LoadScatteringWaitPeriod() {
-  SetScatteringWaitPeriod(
-      TimeDelta::FromSeconds(GetPersistedValue(kPrefsWallClockWaitPeriod)));
+  SetScatteringWaitPeriod(TimeDelta::FromSeconds(
+      GetPersistedValue(kPrefsWallClockWaitPeriod, prefs_)));
 }
 
 void PayloadState::SetScatteringWaitPeriod(TimeDelta wait_period) {
@@ -939,7 +926,7 @@
 }
 
 void PayloadState::LoadUrlSwitchCount() {
-  SetUrlSwitchCount(GetPersistedValue(kPrefsUrlSwitchCount));
+  SetUrlSwitchCount(GetPersistedValue(kPrefsUrlSwitchCount, prefs_));
 }
 
 void PayloadState::SetUrlSwitchCount(uint32_t url_switch_count) {
@@ -950,7 +937,7 @@
 }
 
 void PayloadState::LoadUrlFailureCount() {
-  SetUrlFailureCount(GetPersistedValue(kPrefsCurrentUrlFailureCount));
+  SetUrlFailureCount(GetPersistedValue(kPrefsCurrentUrlFailureCount, prefs_));
 }
 
 void PayloadState::SetUrlFailureCount(uint32_t url_failure_count) {
@@ -1033,12 +1020,8 @@
 }
 
 void PayloadState::SetUpdateTimestampStart(const Time& value) {
-  CHECK(prefs_);
   update_timestamp_start_ = value;
-  prefs_->SetInt64(kPrefsUpdateTimestampStart,
-                   update_timestamp_start_.ToInternalValue());
-  LOG(INFO) << "Update Timestamp Start = "
-            << utils::ToString(update_timestamp_start_);
+  metrics_utils::SetUpdateTimestampStart(value, prefs_);
 }
 
 void PayloadState::SetUpdateTimestampEnd(const Time& value) {
@@ -1084,7 +1067,7 @@
 }
 
 void PayloadState::LoadNumReboots() {
-  SetNumReboots(GetPersistedValue(kPrefsNumReboots));
+  SetNumReboots(GetPersistedValue(kPrefsNumReboots, prefs_));
 }
 
 void PayloadState::LoadRollbackVersion() {
@@ -1136,7 +1119,7 @@
 
 void PayloadState::LoadCurrentBytesDownloaded(DownloadSource source) {
   string key = GetPrefsKey(kPrefsCurrentBytesDownloaded, source);
-  SetCurrentBytesDownloaded(source, GetPersistedValue(key), true);
+  SetCurrentBytesDownloaded(source, GetPersistedValue(key, prefs_), true);
 }
 
 void PayloadState::SetCurrentBytesDownloaded(
@@ -1160,7 +1143,7 @@
 
 void PayloadState::LoadTotalBytesDownloaded(DownloadSource source) {
   string key = GetPrefsKey(kPrefsTotalBytesDownloaded, source);
-  SetTotalBytesDownloaded(source, GetPersistedValue(key), true);
+  SetTotalBytesDownloaded(source, GetPersistedValue(key, prefs_), true);
 }
 
 void PayloadState::SetTotalBytesDownloaded(
@@ -1184,7 +1167,7 @@
 }
 
 void PayloadState::LoadNumResponsesSeen() {
-  SetNumResponsesSeen(GetPersistedValue(kPrefsNumResponsesSeen));
+  SetNumResponsesSeen(GetPersistedValue(kPrefsNumResponsesSeen, prefs_));
 }
 
 void PayloadState::SetNumResponsesSeen(int num_responses_seen) {
@@ -1225,24 +1208,6 @@
   }
 }
 
-void PayloadState::CreateSystemUpdatedMarkerFile() {
-  CHECK(prefs_);
-  int64_t value = system_state_->clock()->GetWallclockTime().ToInternalValue();
-  prefs_->SetInt64(kPrefsSystemUpdatedMarker, value);
-}
-
-void PayloadState::BootedIntoUpdate(TimeDelta time_to_reboot) {
-  // Send |time_to_reboot| as a UMA stat.
-  string metric = metrics::kMetricTimeToRebootMinutes;
-  system_state_->metrics_lib()->SendToUMA(metric,
-                                          time_to_reboot.InMinutes(),
-                                          0,         // min: 0 minute
-                                          30*24*60,  // max: 1 month (approx)
-                                          kNumDefaultUmaBuckets);
-  LOG(INFO) << "Uploading " << utils::FormatTimeDelta(time_to_reboot)
-            << " for metric " <<  metric;
-}
-
 void PayloadState::UpdateEngineStarted() {
   // Flush previous state from abnormal attempt failure, if any.
   ReportAndClearPersistedAttemptMetrics();
@@ -1252,24 +1217,11 @@
   if (!system_state_->system_rebooted())
     return;
 
-  // Figure out if we just booted into a new update
-  if (prefs_->Exists(kPrefsSystemUpdatedMarker)) {
-    int64_t stored_value;
-    if (prefs_->GetInt64(kPrefsSystemUpdatedMarker, &stored_value)) {
-      Time system_updated_at = Time::FromInternalValue(stored_value);
-      if (!system_updated_at.is_null()) {
-        TimeDelta time_to_reboot =
-            system_state_->clock()->GetWallclockTime() - system_updated_at;
-        if (time_to_reboot.ToInternalValue() < 0) {
-          LOG(ERROR) << "time_to_reboot is negative - system_updated_at: "
-                     << utils::ToString(system_updated_at);
-        } else {
-          BootedIntoUpdate(time_to_reboot);
-        }
-      }
-    }
-    prefs_->Delete(kPrefsSystemUpdatedMarker);
-  }
+  // Report time_to_reboot if we booted into a new update.
+  metrics_utils::LoadAndReportTimeToReboot(
+      system_state_->metrics_reporter(), prefs_, system_state_->clock());
+  prefs_->Delete(kPrefsSystemUpdatedMarker);
+
   // Check if it is needed to send metrics about a failed reboot into a new
   // version.
   ReportFailedBootIfNeeded();
@@ -1303,15 +1255,8 @@
       }
 
       // Report the UMA metric of the current boot failure.
-      string metric = metrics::kMetricFailedUpdateCount;
-      LOG(INFO) << "Uploading " << target_attempt
-                << " (count) for metric " <<  metric;
-      system_state_->metrics_lib()->SendToUMA(
-           metric,
-           target_attempt,
-           1,    // min value
-           50,   // max value
-           kNumDefaultUmaBuckets);
+      system_state_->metrics_reporter()->ReportFailedUpdateCount(
+          target_attempt);
     } else {
       prefs_->Delete(kPrefsTargetVersionAttempt);
       prefs_->Delete(kPrefsTargetVersionUniqueId);
@@ -1368,7 +1313,7 @@
 }
 
 void PayloadState::LoadP2PNumAttempts() {
-  SetP2PNumAttempts(GetPersistedValue(kPrefsP2PNumAttempts));
+  SetP2PNumAttempts(GetPersistedValue(kPrefsP2PNumAttempts, prefs_));
 }
 
 Time PayloadState::GetP2PFirstAttemptTimestamp() {
@@ -1385,7 +1330,8 @@
 }
 
 void PayloadState::LoadP2PFirstAttemptTimestamp() {
-  int64_t stored_value = GetPersistedValue(kPrefsP2PFirstAttemptTimestamp);
+  int64_t stored_value =
+      GetPersistedValue(kPrefsP2PFirstAttemptTimestamp, prefs_);
   Time stored_time = Time::FromInternalValue(stored_value);
   SetP2PFirstAttemptTimestamp(stored_time);
 }
diff --git a/payload_state.h b/payload_state.h
index 699fc74..24e9900 100644
--- a/payload_state.h
+++ b/payload_state.h
@@ -17,6 +17,7 @@
 #ifndef UPDATE_ENGINE_PAYLOAD_STATE_H_
 #define UPDATE_ENGINE_PAYLOAD_STATE_H_
 
+#include <algorithm>
 #include <string>
 #include <vector>
 
@@ -24,7 +25,7 @@
 #include <gtest/gtest_prod.h>  // for FRIEND_TEST
 
 #include "update_engine/common/prefs_interface.h"
-#include "update_engine/metrics.h"
+#include "update_engine/metrics_constants.h"
 #include "update_engine/payload_state_interface.h"
 
 namespace chromeos_update_engine {
@@ -240,10 +241,6 @@
   // reset on a new update.
   void ResetDownloadSourcesOnNewUpdate();
 
-  // Returns the persisted value from prefs_ for the given key. It also
-  // validates that the value returned is non-negative.
-  int64_t GetPersistedValue(const std::string& key);
-
   // Calculates the response "signature", which is basically a string composed
   // of the subset of the fields in the current response that affect the
   // behavior of the PayloadState.
@@ -404,16 +401,7 @@
   // increments num_reboots.
   void UpdateNumReboots();
 
-  // Writes the current wall-clock time to the kPrefsSystemUpdatedMarker
-  // state variable.
-  void CreateSystemUpdatedMarkerFile();
 
-  // Called at program startup if the device booted into a new update.
-  // The |time_to_reboot| parameter contains the (wall-clock) duration
-  // from when the update successfully completed (the value written
-  // into the kPrefsSystemUpdatedMarker state variable) until the device
-  // was booted into the update (current wall-clock time).
-  void BootedIntoUpdate(base::TimeDelta time_to_reboot);
 
   // Loads the |kPrefsP2PFirstAttemptTimestamp| state variable from disk
   // into |p2p_first_attempt_timestamp_|.
diff --git a/payload_state_unittest.cc b/payload_state_unittest.cc
index 4546180..f1c3835 100644
--- a/payload_state_unittest.cc
+++ b/payload_state_unittest.cc
@@ -31,6 +31,7 @@
 #include "update_engine/common/test_utils.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/fake_system_state.h"
+#include "update_engine/metrics_reporter_interface.h"
 #include "update_engine/omaha_request_action.h"
 
 using base::Time;
@@ -41,7 +42,7 @@
 using testing::Mock;
 using testing::NiceMock;
 using testing::Return;
-using testing::SetArgumentPointee;
+using testing::SetArgPointee;
 using testing::_;
 
 namespace chromeos_update_engine {
@@ -311,11 +312,6 @@
 
   EXPECT_TRUE(payload_state.Initialize(&fake_system_state));
 
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(_, _, _, _, _))
-    .Times(AnyNumber());
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(_, _, _))
-    .Times(AnyNumber());
-
   // Set the first response.
   SetupPayloadStateWith2Urls(
       "Hash5823", true, false, &payload_state, &response);
@@ -615,7 +611,7 @@
   EXPECT_CALL(*prefs2, GetInt64(kPrefsFullPayloadAttemptNumber, _))
     .Times(AtLeast(1));
   EXPECT_CALL(*prefs2, GetInt64(kPrefsCurrentUrlIndex, _))
-      .WillRepeatedly(DoAll(SetArgumentPointee<1>(2), Return(true)));
+      .WillRepeatedly(DoAll(SetArgPointee<1>(2), Return(true)));
   EXPECT_CALL(*prefs2, GetInt64(kPrefsCurrentUrlFailureCount, _))
     .Times(AtLeast(1));
   EXPECT_CALL(*prefs2, GetInt64(kPrefsUrlSwitchCount, _))
@@ -873,26 +869,9 @@
   EXPECT_EQ(p2p_total,
             payload_state.GetTotalBytesDownloaded(kDownloadSourceHttpPeer));
 
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(_, _, _, _, _))
-    .Times(AnyNumber());
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(_, _, _))
-    .Times(AnyNumber());
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricSuccessfulUpdateUrlSwitchCount,
-      3, _, _, _));
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricSuccessfulUpdateTotalDurationMinutes,
-      _, _, _, _));
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricSuccessfulUpdateDownloadOverheadPercentage,
-      314, _, _, _));
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(
-      metrics::kMetricAttemptPayloadType, kPayloadTypeFull, kNumPayloadTypes));
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(
-      metrics::kMetricSuccessfulUpdatePayloadType, kPayloadTypeFull,
-      kNumPayloadTypes));
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricSuccessfulUpdateAttemptCount, 1, _, _, _));
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportSuccessfulUpdateMetrics(
+                  1, _, kPayloadTypeFull, _, _, 314, _, _, 3));
 
   payload_state.UpdateSucceeded();
 
@@ -928,12 +907,21 @@
             payload_state.GetTotalBytesDownloaded(kDownloadSourceHttpServer));
 
   // Check that only HTTP is reported as a download source.
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(_, _, _, _, _))
-    .Times(AnyNumber());
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricSuccessfulUpdateDownloadSourcesUsed,
-      (1 << kDownloadSourceHttpServer),
-      _, _, _));
+  int64_t total_bytes[kNumDownloadSources] = {};
+  total_bytes[kDownloadSourceHttpServer] = num_bytes;
+
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportSuccessfulUpdateMetrics(
+                  _,
+                  _,
+                  _,
+                  _,
+                  test_utils::DownloadSourceMatcher(total_bytes),
+                  _,
+                  _,
+                  _,
+                  _))
+      .Times(1);
 
   payload_state.UpdateSucceeded();
 }
@@ -1024,7 +1012,7 @@
   // Let's verify we can reload it correctly.
   EXPECT_CALL(*mock_powerwash_safe_prefs, GetString(
       kPrefsRollbackVersion, _)).WillOnce(DoAll(
-          SetArgumentPointee<1>(rollback_version), Return(true)));
+          SetArgPointee<1>(rollback_version), Return(true)));
   EXPECT_CALL(*mock_powerwash_safe_prefs, SetString(kPrefsRollbackVersion,
                                                     rollback_version));
   payload_state.LoadRollbackVersion();
@@ -1032,15 +1020,10 @@
 
   // Check that we report only UpdateEngine.Rollback.* metrics in
   // UpdateSucceeded().
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(_, _, _, _, _))
-    .Times(0);
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(_, _, _))
-    .Times(0);
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(),
-              SendEnumToUMA(
-                  metrics::kMetricRollbackResult,
-                  static_cast<int>(metrics::RollbackResult::kSuccess),
-                  static_cast<int>(metrics::RollbackResult::kNumConstants)));
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportRollbackMetrics(metrics::RollbackResult::kSuccess))
+      .Times(1);
+
   payload_state.UpdateSucceeded();
 }
 
@@ -1115,8 +1098,8 @@
   FakePrefs fake_prefs;
 
   // Set the clock to a well-known time (t = 30 seconds).
-  fake_clock.SetWallclockTime(Time::FromInternalValue(
-      30 * Time::kMicrosecondsPerSecond));
+  fake_clock.SetMonotonicTime(
+      Time::FromInternalValue(30 * Time::kMicrosecondsPerSecond));
 
   fake_system_state.set_clock(&fake_clock);
   fake_system_state.set_prefs(&fake_prefs);
@@ -1134,15 +1117,14 @@
   // (t = 500 seconds). We do this by using a new PayloadState object
   // and checking that it emits the right UMA metric with the right
   // value.
-  fake_clock.SetWallclockTime(Time::FromInternalValue(
-      500 * Time::kMicrosecondsPerSecond));
+  fake_clock.SetMonotonicTime(
+      Time::FromInternalValue(500 * Time::kMicrosecondsPerSecond));
   PayloadState payload_state2;
   EXPECT_TRUE(payload_state2.Initialize(&fake_system_state));
 
   // Expect 500 - 30 seconds = 470 seconds ~= 7 min 50 sec
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricTimeToRebootMinutes,
-      7, _, _, _));
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportTimeToReboot(7));
   fake_system_state.set_system_rebooted(true);
 
   payload_state2.UpdateEngineStarted();
@@ -1154,6 +1136,8 @@
 TEST(PayloadStateTest, RestartAfterCrash) {
   PayloadState payload_state;
   FakeSystemState fake_system_state;
+  testing::StrictMock<MockMetricsReporter> mock_metrics_reporter;
+  fake_system_state.set_metrics_reporter(&mock_metrics_reporter);
   NiceMock<MockPrefs>* prefs = fake_system_state.mock_prefs();
 
   EXPECT_TRUE(payload_state.Initialize(&fake_system_state));
@@ -1168,10 +1152,6 @@
   EXPECT_CALL(*prefs, GetBoolean(_, _)).Times(0);
   EXPECT_CALL(*prefs, GetBoolean(kPrefsAttemptInProgress, _));
 
-  // No metrics are reported after a crash.
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(),
-              SendToUMA(_, _, _, _, _)).Times(0);
-
   // Simulate an update_engine restart without a reboot.
   fake_system_state.set_system_rebooted(false);
 
@@ -1184,11 +1164,9 @@
 
   // If there's no marker at startup, ensure we don't report a metric.
   EXPECT_TRUE(payload_state.Initialize(&fake_system_state));
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(),
-      SendEnumToUMA(
-          metrics::kMetricAttemptResult,
-          static_cast<int>(metrics::AttemptResult::kAbnormalTermination),
-          _)).Times(0);
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportAbnormallyTerminatedUpdateAttemptMetrics())
+      .Times(0);
   payload_state.UpdateEngineStarted();
 }
 
@@ -1204,11 +1182,9 @@
 
   EXPECT_TRUE(payload_state.Initialize(&fake_system_state));
 
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(),
-      SendEnumToUMA(
-          metrics::kMetricAttemptResult,
-          static_cast<int>(metrics::AttemptResult::kAbnormalTermination),
-          _)).Times(1);
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportAbnormallyTerminatedUpdateAttemptMetrics())
+      .Times(1);
   payload_state.UpdateEngineStarted();
 
   EXPECT_FALSE(fake_prefs.Exists(kPrefsAttemptInProgress));
@@ -1228,15 +1204,9 @@
   response.packages.resize(1);
   payload_state.SetResponse(response);
 
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(_, _, _, _, _))
-    .Times(AnyNumber());
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(_, _, _))
-    .Times(AnyNumber());
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(),
-      SendEnumToUMA(
-          metrics::kMetricAttemptResult,
-          static_cast<int>(metrics::AttemptResult::kAbnormalTermination),
-          _)).Times(0);
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportAbnormallyTerminatedUpdateAttemptMetrics())
+      .Times(0);
 
   // Attempt not in progress, should be clear.
   EXPECT_FALSE(fake_prefs.Exists(kPrefsAttemptInProgress));
@@ -1275,7 +1245,7 @@
 
   // Test with device policy not allowing http updates.
   EXPECT_CALL(disable_http_policy, GetHttpDownloadsEnabled(_))
-      .WillRepeatedly(DoAll(SetArgumentPointee<0>(false), Return(true)));
+      .WillRepeatedly(DoAll(SetArgPointee<0>(false), Return(true)));
 
   // Reset state and set again.
   SetupPayloadStateWith2Urls(
@@ -1304,7 +1274,7 @@
   policy::MockDevicePolicy enable_http_policy;
   fake_system_state.set_device_policy(&enable_http_policy);
   EXPECT_CALL(enable_http_policy, GetHttpDownloadsEnabled(_))
-      .WillRepeatedly(DoAll(SetArgumentPointee<0>(true), Return(true)));
+      .WillRepeatedly(DoAll(SetArgPointee<0>(true), Return(true)));
 
   // Now, set the same response using the same hash
   // so that we can test that the state is reset not because of the
@@ -1335,14 +1305,9 @@
 
   // Simulate a successful download and update.
   payload_state.DownloadComplete();
-
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(_, _, _))
-    .Times(AnyNumber());
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(
-      metrics::kMetricAttemptPayloadType, kPayloadTypeDelta, kNumPayloadTypes));
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(
-      metrics::kMetricSuccessfulUpdatePayloadType, kPayloadTypeDelta,
-      kNumPayloadTypes));
+  EXPECT_CALL(
+      *fake_system_state.mock_metrics_reporter(),
+      ReportSuccessfulUpdateMetrics(_, _, kPayloadTypeDelta, _, _, _, _, _, _));
   payload_state.UpdateSucceeded();
 
   // Mock the request to a request where the delta was disabled but Omaha sends
@@ -1356,12 +1321,9 @@
 
   payload_state.DownloadComplete();
 
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(
-      metrics::kMetricAttemptPayloadType, kPayloadTypeDelta,
-      kNumPayloadTypes));
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(
-      metrics::kMetricSuccessfulUpdatePayloadType, kPayloadTypeDelta,
-      kNumPayloadTypes));
+  EXPECT_CALL(
+      *fake_system_state.mock_metrics_reporter(),
+      ReportSuccessfulUpdateMetrics(_, _, kPayloadTypeDelta, _, _, _, _, _, _));
   payload_state.UpdateSucceeded();
 }
 
@@ -1382,14 +1344,9 @@
   // Simulate a successful download and update.
   payload_state.DownloadComplete();
 
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(_, _, _))
-    .Times(AnyNumber());
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(
-      metrics::kMetricAttemptPayloadType, kPayloadTypeForcedFull,
-      kNumPayloadTypes));
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(
-      metrics::kMetricSuccessfulUpdatePayloadType, kPayloadTypeForcedFull,
-      kNumPayloadTypes));
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportSuccessfulUpdateMetrics(
+                  _, _, kPayloadTypeForcedFull, _, _, _, _, _, _));
   payload_state.UpdateSucceeded();
 }
 
@@ -1411,14 +1368,9 @@
   // Simulate a successful download and update.
   payload_state.DownloadComplete();
 
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(_, _, _))
-    .Times(AnyNumber());
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(
-      metrics::kMetricAttemptPayloadType, kPayloadTypeFull,
-      kNumPayloadTypes));
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendEnumToUMA(
-      metrics::kMetricSuccessfulUpdatePayloadType, kPayloadTypeFull,
-      kNumPayloadTypes));
+  EXPECT_CALL(
+      *fake_system_state.mock_metrics_reporter(),
+      ReportSuccessfulUpdateMetrics(_, _, kPayloadTypeFull, _, _, _, _, _, _));
   payload_state.UpdateSucceeded();
 }
 
@@ -1439,27 +1391,27 @@
   payload_state.ExpectRebootInNewVersion("Version:12345678");
 
   // Reboot into the same environment to get an UMA metric with a value of 1.
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricFailedUpdateCount, 1, _, _, _));
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportFailedUpdateCount(1));
   payload_state.ReportFailedBootIfNeeded();
-  Mock::VerifyAndClearExpectations(fake_system_state.mock_metrics_lib());
+  Mock::VerifyAndClearExpectations(fake_system_state.mock_metrics_reporter());
 
   // Simulate a second update and reboot into the same environment, this should
   // send a value of 2.
   payload_state.ExpectRebootInNewVersion("Version:12345678");
 
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricFailedUpdateCount, 2, _, _, _));
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportFailedUpdateCount(2));
   payload_state.ReportFailedBootIfNeeded();
-  Mock::VerifyAndClearExpectations(fake_system_state.mock_metrics_lib());
+  Mock::VerifyAndClearExpectations(fake_system_state.mock_metrics_reporter());
 
   // Simulate a third failed reboot to new version, but this time for a
   // different payload. This should send a value of 1 this time.
   payload_state.ExpectRebootInNewVersion("Version:3141592");
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricFailedUpdateCount, 1, _, _, _));
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportFailedUpdateCount(1));
   payload_state.ReportFailedBootIfNeeded();
-  Mock::VerifyAndClearExpectations(fake_system_state.mock_metrics_lib());
+  Mock::VerifyAndClearExpectations(fake_system_state.mock_metrics_reporter());
 }
 
 TEST(PayloadStateTest, RebootAfterUpdateSucceed) {
@@ -1484,8 +1436,8 @@
   // Change the BootDevice to a different one, no metric should be sent.
   fake_boot_control->SetCurrentSlot(1);
 
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricFailedUpdateCount, _, _, _, _))
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportFailedUpdateCount(_))
       .Times(0);
   payload_state.ReportFailedBootIfNeeded();
 
@@ -1511,8 +1463,8 @@
   payload_state.UpdateSucceeded();
   payload_state.ExpectRebootInNewVersion("Version:12345678");
 
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricFailedUpdateCount, _, _, _, _))
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportFailedUpdateCount(_))
       .Times(0);
 
   // Cancel the applied update.
@@ -1530,8 +1482,8 @@
   fake_system_state.set_prefs(&fake_prefs);
   EXPECT_TRUE(payload_state.Initialize(&fake_system_state));
 
-  EXPECT_CALL(*fake_system_state.mock_metrics_lib(), SendToUMA(
-      metrics::kMetricFailedUpdateCount, _, _, _, _))
+  EXPECT_CALL(*fake_system_state.mock_metrics_reporter(),
+              ReportFailedUpdateCount(_))
       .Times(0);
 
   // Simulate a reboot in this environment.
diff --git a/power_manager_chromeos.cc b/power_manager_chromeos.cc
index e175f95..23fb032 100644
--- a/power_manager_chromeos.cc
+++ b/power_manager_chromeos.cc
@@ -16,6 +16,8 @@
 
 #include "update_engine/power_manager_chromeos.h"
 
+#include <memory>
+
 #include <power_manager/dbus-constants.h>
 #include <power_manager/dbus-proxies.h>
 
@@ -37,7 +39,9 @@
             << ::power_manager::kRequestRestartMethod;
   brillo::ErrorPtr error;
   return power_manager_proxy_.RequestRestart(
-      ::power_manager::REQUEST_RESTART_FOR_UPDATE, &error);
+      ::power_manager::REQUEST_RESTART_FOR_UPDATE,
+      "update_engine applying update",
+      &error);
 }
 
 }  // namespace chromeos_update_engine
diff --git a/proxy_resolver_unittest.cc b/proxy_resolver_unittest.cc
index 070b361..484aae1 100644
--- a/proxy_resolver_unittest.cc
+++ b/proxy_resolver_unittest.cc
@@ -22,7 +22,6 @@
 #include <gtest/gtest.h>
 
 #include <base/bind.h>
-#include <brillo/bind_lambda.h>
 #include <brillo/message_loops/fake_message_loop.h>
 
 using std::deque;
diff --git a/pylintrc b/pylintrc
index f83f8c6..80a7605 100644
--- a/pylintrc
+++ b/pylintrc
@@ -149,7 +149,7 @@
 # (useful for modules/projects where namespaces are manipulated during runtime
 # and thus existing member attributes cannot be deduced by static analysis. It
 # supports qualified module names, as well as Unix pattern matching.
-ignored-modules=
+ignored-modules=update_payload.update_metadata_pb2
 
 # List of classes names for which member attributes should not be checked
 # (useful for classes with attributes dynamically set). This supports can work
@@ -263,7 +263,7 @@
 bad-functions=map,filter,input,apply,reduce
 
 # Good variable names which should always be accepted, separated by a comma
-good-names=i,j,k,ex,x,_
+good-names=i,j,k,ex,x,_,main
 
 # Bad variable names which should always be refused, separated by a comma
 bad-names=foo,bar,baz,toto,tutu,tata
diff --git a/real_system_state.cc b/real_system_state.cc
index 5cbf723..8e7ad51 100644
--- a/real_system_state.cc
+++ b/real_system_state.cc
@@ -16,23 +16,24 @@
 
 #include "update_engine/real_system_state.h"
 
+#include <memory>
 #include <string>
 
 #include <base/bind.h>
 #include <base/files/file_util.h>
 #include <base/location.h>
 #include <base/time/time.h>
-#include <brillo/make_unique_ptr.h>
 #include <brillo/message_loops/message_loop.h>
-#if USE_LIBCROS
+#if USE_CHROME_KIOSK_APP
 #include <chromeos/dbus/service_constants.h>
-#endif  // USE_LIBCROS
+#endif  // USE_CHROME_KIOSK_APP
 
 #include "update_engine/common/boot_control.h"
 #include "update_engine/common/boot_control_stub.h"
 #include "update_engine/common/constants.h"
 #include "update_engine/common/hardware.h"
 #include "update_engine/common/utils.h"
+#include "update_engine/metrics_reporter_omaha.h"
 #if USE_DBUS
 #include "update_engine/dbus_connection.h"
 #endif  // USE_DBUS
@@ -50,13 +51,13 @@
 }
 
 bool RealSystemState::Initialize() {
-  metrics_lib_.Init();
+  metrics_reporter_.Initialize();
 
   boot_control_ = boot_control::CreateBootControl();
   if (!boot_control_) {
     LOG(WARNING) << "Unable to create BootControl instance, using stub "
                  << "instead. All update attempts will fail.";
-    boot_control_ = brillo::make_unique_ptr(new BootControlStub());
+    boot_control_ = std::make_unique<BootControlStub>();
   }
 
   hardware_ = hardware::CreateHardware();
@@ -65,14 +66,10 @@
     return false;
   }
 
-#if USE_LIBCROS
+#if USE_CHROME_KIOSK_APP
   libcros_proxy_.reset(new org::chromium::LibCrosServiceInterfaceProxy(
       DBusConnection::Get()->GetDBus(), chromeos::kLibCrosServiceName));
-  network_proxy_service_proxy_.reset(
-      new org::chromium::NetworkProxyServiceInterfaceProxy(
-          DBusConnection::Get()->GetDBus(),
-          chromeos::kNetworkProxyServiceName));
-#endif  // USE_LIBCROS
+#endif  // USE_CHROME_KIOSK_APP
 
   LOG_IF(INFO, !hardware_->IsNormalBootMode()) << "Booted in dev mode.";
   LOG_IF(INFO, !hardware_->IsOfficialBuild()) << "Booted non-official build.";
@@ -143,27 +140,22 @@
       new CertificateChecker(prefs_.get(), &openssl_wrapper_));
   certificate_checker_->Init();
 
-#if USE_LIBCROS
-  org::chromium::NetworkProxyServiceInterfaceProxyInterface* net_proxy =
-      network_proxy_service_proxy_.get();
-  org::chromium::LibCrosServiceInterfaceProxyInterface* libcros_proxy =
-      libcros_proxy_.get();
-#else
-  org::chromium::NetworkProxyServiceInterfaceProxyInterface* net_proxy =
-      nullptr;
-  org::chromium::LibCrosServiceInterfaceProxyInterface* libcros_proxy =
-      nullptr;
-#endif  // USE_LIBCROS
+  update_attempter_.reset(new UpdateAttempter(this,
+                                              certificate_checker_.get()));
 
   // Initialize the UpdateAttempter before the UpdateManager.
-  update_attempter_.reset(new UpdateAttempter(this, certificate_checker_.get(),
-                                              net_proxy));
   update_attempter_->Init();
 
   // Initialize the Update Manager using the default state factory.
   chromeos_update_manager::State* um_state =
-      chromeos_update_manager::DefaultStateFactory(
-          &policy_provider_, libcros_proxy, this);
+      chromeos_update_manager::DefaultStateFactory(&policy_provider_,
+#if USE_CHROME_KIOSK_APP
+                                                   libcros_proxy_.get(),
+#else
+                                                   nullptr,
+#endif  // USE_CHROME_KIOSK_APP
+                                                   this);
+
   if (!um_state) {
     LOG(ERROR) << "Failed to initialize the Update Manager.";
     return false;
diff --git a/real_system_state.h b/real_system_state.h
index 64964cd..49f7c31 100644
--- a/real_system_state.h
+++ b/real_system_state.h
@@ -22,13 +22,11 @@
 #include <memory>
 #include <set>
 
-#include <metrics/metrics_library.h>
 #include <policy/device_policy.h>
 
-#if USE_LIBCROS
+#if USE_CHROME_KIOSK_APP
 #include <libcros/dbus-proxies.h>
-#include <network_proxy/dbus-proxies.h>
-#endif  // USE_LIBCROS
+#endif  // USE_CHROME_KIOSK_APP
 
 #include "update_engine/certificate_checker.h"
 #include "update_engine/common/boot_control_interface.h"
@@ -37,6 +35,8 @@
 #include "update_engine/common/prefs.h"
 #include "update_engine/connection_manager_interface.h"
 #include "update_engine/daemon_state_interface.h"
+#include "update_engine/metrics_reporter_interface.h"
+#include "update_engine/metrics_reporter_omaha.h"
 #include "update_engine/p2p_manager.h"
 #include "update_engine/payload_state.h"
 #include "update_engine/power_manager_interface.h"
@@ -92,8 +92,8 @@
 
   inline HardwareInterface* hardware() override { return hardware_.get(); }
 
-  inline MetricsLibraryInterface* metrics_lib() override {
-    return &metrics_lib_;
+  inline MetricsReporterInterface* metrics_reporter() override {
+    return &metrics_reporter_;
   }
 
   inline PrefsInterface* prefs() override { return prefs_.get(); }
@@ -127,12 +127,10 @@
   inline bool system_rebooted() override { return system_rebooted_; }
 
  private:
-#if USE_LIBCROS
   // Real DBus proxies using the DBus connection.
+#if USE_CHROME_KIOSK_APP
   std::unique_ptr<org::chromium::LibCrosServiceInterfaceProxy> libcros_proxy_;
-  std::unique_ptr<org::chromium::NetworkProxyServiceInterfaceProxy>
-      network_proxy_service_proxy_;
-#endif  // USE_LIBCROS
+#endif  // USE_CHROME_KIOSK_APP
 
   // Interface for the power manager.
   std::unique_ptr<PowerManagerInterface> power_manager_;
@@ -153,8 +151,8 @@
   // Interface for the hardware functions.
   std::unique_ptr<HardwareInterface> hardware_;
 
-  // The Metrics Library interface for reporting UMA stats.
-  MetricsLibrary metrics_lib_;
+  // The Metrics reporter for reporting UMA stats.
+  MetricsReporterOmaha metrics_reporter_;
 
   // Interface for persisted store.
   std::unique_ptr<PrefsInterface> prefs_;
diff --git a/sample_images/generate_images.sh b/sample_images/generate_images.sh
index 6a0d1ea..8478682 100755
--- a/sample_images/generate_images.sh
+++ b/sample_images/generate_images.sh
@@ -26,12 +26,15 @@
 # cleanup <path>
 # Unmount and remove the mountpoint <path>
 cleanup() {
-  if ! sudo umount "$1" 2>/dev/null; then
-    if mountpoint -q "$1"; then
-      sync && sudo umount "$1"
+  local path="$1"
+  if ! sudo umount "${path}" 2>/dev/null; then
+    if mountpoint -q "${path}"; then
+      sync && sudo umount "${path}"
     fi
   fi
-  rmdir "$1"
+  if [ -n "${path}" ]; then
+    sudo rm -rf "${path}"
+  fi
 }
 
 # add_files_default <mntdir> <block_size>
@@ -203,10 +206,11 @@
 # generate_fs <filename> <kind> <size> [block_size] [block_groups]
 generate_fs() {
   local filename="$1"
-  local kind="$2"
-  local size="$3"
-  local block_size="${4:-4096}"
-  local block_groups="${5:-}"
+  local type="$2"
+  local kind="$3"
+  local size="$4"
+  local block_size="${5:-4096}"
+  local block_groups="${6:-}"
 
   local mkfs_opts=( -q -F -b "${block_size}" -L "ROOT-TEST" -t ext2 )
   if [[ -n "${block_groups}" ]]; then
@@ -215,16 +219,17 @@
 
   local mntdir=$(mktemp --tmpdir -d generate_ext2.XXXXXX)
   trap 'cleanup "${mntdir}"; rm -f "${filename}"' INT TERM EXIT
-
   # Cleanup old image.
   if [[ -e "${filename}" ]]; then
     rm -f "${filename}"
   fi
-  truncate --size="${size}" "${filename}"
 
-  mkfs.ext2 "${mkfs_opts[@]}" "${filename}"
-  sudo mount "${filename}" "${mntdir}" -o loop
+  if [[ "${type}" == "ext2" ]]; then
+    truncate --size="${size}" "${filename}"
 
+    mkfs.ext2 "${mkfs_opts[@]}" "${filename}"
+    sudo mount "${filename}" "${mntdir}" -o loop
+  fi
   case "${kind}" in
     unittest)
       add_files_ue_settings "${mntdir}" "${block_size}"
@@ -237,6 +242,10 @@
       ;;
   esac
 
+  if [[ "${type}" == "sqfs" ]]; then
+    mksquashfs "${mntdir}" "${filename}"
+  fi
+
   cleanup "${mntdir}"
   trap - INT TERM EXIT
 }
@@ -253,10 +262,14 @@
 
 main() {
   # Add more sample images here.
-  generate_image disk_ext2_1k default $((1024 * 1024)) 1024
-  generate_image disk_ext2_4k default $((1024 * 4096)) 4096
-  generate_image disk_ext2_4k_empty empty $((1024 * 4096)) 4096
-  generate_image disk_ext2_unittest unittest $((1024 * 4096)) 4096
+  generate_image disk_ext2_1k ext2 default $((1024 * 1024)) 1024
+  generate_image disk_ext2_4k ext2 default $((1024 * 4096)) 4096
+  generate_image disk_ext2_4k_empty ext2 empty $((1024 * 4096)) 4096
+  generate_image disk_ext2_unittest ext2 unittest $((1024 * 4096)) 4096
+
+  # Add squashfs sample images.
+  generate_image disk_sqfs_empty sqfs empty $((1024 * 4096)) 4096
+  generate_image disk_sqfs_default sqfs default $((1024 * 4096)) 4096
 
   # Generate the tarball and delete temporary images.
   echo "Packing tar file sample_images.tar.bz2"
diff --git a/sample_images/sample_images.tar.bz2 b/sample_images/sample_images.tar.bz2
index 72f4eb5..6215482 100644
--- a/sample_images/sample_images.tar.bz2
+++ b/sample_images/sample_images.tar.bz2
Binary files differ
diff --git a/scripts/blockdiff.py b/scripts/blockdiff.py
new file mode 100755
index 0000000..1dc60a6
--- /dev/null
+++ b/scripts/blockdiff.py
@@ -0,0 +1,115 @@
+#!/usr/bin/python2
+#
+# Copyright (c) 2013 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.
+
+"""Block diff utility."""
+
+from __future__ import print_function
+
+import optparse
+import sys
+
+
+class BlockDiffError(Exception):
+  pass
+
+
+def BlockDiff(block_size, file1, file2, name1, name2, max_length=-1):
+  """Performs a binary diff of two files by blocks.
+
+  Args:
+    block_size: the size of a block to diff by
+    file1: first file object
+    file2: second file object
+    name1: name of first file (for error reporting)
+    name2: name of second file (for error reporting)
+    max_length: the maximum length to read/diff in bytes (optional)
+  Returns:
+    A list of (start, length) pairs representing block extents that differ
+    between the two files.
+  Raises:
+    BlockDiffError if there were errors while diffing.
+
+  """
+  if max_length < 0:
+    max_length = sys.maxint
+  diff_list = []
+  num_blocks = extent_start = extent_length = 0
+  while max_length or extent_length:
+    read_length = min(max_length, block_size)
+    data1 = file1.read(read_length)
+    data2 = file2.read(read_length)
+    if len(data1) != len(data2):
+      raise BlockDiffError('read %d bytes from %s but %d bytes from %s' %
+                           (len(data1), name1, len(data2), name2))
+
+    if data1 != data2:
+      # Data is different, mark it down.
+      if extent_length:
+        # Stretch the current diff extent.
+        extent_length += 1
+      else:
+        # Start a new diff extent.
+        extent_start = num_blocks
+        extent_length = 1
+    elif extent_length:
+      # Record the previous extent.
+      diff_list.append((extent_start, extent_length))
+      extent_length = 0
+
+    # Are we done reading?
+    if not data1:
+      break
+
+    max_length -= len(data1)
+    num_blocks += 1
+
+  return diff_list
+
+
+def main(argv):
+  # Parse command-line arguments.
+  parser = optparse.OptionParser(
+      usage='Usage: %prog FILE1 FILE2',
+      description='Compare FILE1 and FILE2 by blocks.')
+
+  parser.add_option('-b', '--block-size', metavar='NUM', type=int, default=4096,
+                    help='the block size to use (default: %default)')
+  parser.add_option('-m', '--max-length', metavar='NUM', type=int, default=-1,
+                    help='maximum number of bytes to compared')
+
+  opts, args = parser.parse_args(argv[1:])
+
+  try:
+    name1, name2 = args
+  except ValueError:
+    parser.error('unexpected number of arguments')
+
+  # Perform the block diff.
+  try:
+    with open(name1) as file1:
+      with open(name2) as file2:
+        diff_list = BlockDiff(opts.block_size, file1, file2, name1, name2,
+                              opts.max_length)
+  except BlockDiffError as e:
+    print('Error: ' % e, file=sys.stderr)
+    return 2
+
+  # Print the diff, if such was found.
+  if diff_list:
+    total_diff_blocks = 0
+    for extent_start, extent_length in diff_list:
+      total_diff_blocks += extent_length
+      print('%d->%d (%d)' %
+            (extent_start, extent_start + extent_length, extent_length))
+
+    print('total diff: %d blocks' % total_diff_blocks)
+    return 1
+
+  return 0
+
+
+if __name__ == '__main__':
+  sys.exit(main(sys.argv))
diff --git a/scripts/brillo_update_payload b/scripts/brillo_update_payload
index 375c0df..65c63f5 100755
--- a/scripts/brillo_update_payload
+++ b/scripts/brillo_update_payload
@@ -1,8 +1,20 @@
 #!/bin/bash
 
-# Copyright 2015 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.
+#
+# Copyright (C) 2015 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
 
 # Script to generate a Brillo update for use by the update engine.
 #
@@ -12,14 +24,15 @@
 #  hash        generate a payload or metadata hash
 #  sign        generate a signed payload
 #  properties  generate a properties file from a payload
+#  verify      verify a payload by recreating a target image.
 #
 #  Generate command arguments:
 #  --payload             generated unsigned payload output file
 #  --source_image        if defined, generate a delta payload from the specified
 #                        image to the target_image
 #  --target_image        the target image that should be sent to clients
-#  --metadata_size_file  if defined, generate a file containing the size of the payload
-#                        metadata in bytes to the specified file
+#  --metadata_size_file  if defined, generate a file containing the size of the
+#                        payload metadata in bytes to the specified file
 #
 #  Hash command arguments:
 #  --unsigned_payload    the input unsigned payload to generate the hash from
@@ -50,6 +63,10 @@
 #  --payload                 the input signed or unsigned payload
 #  --properties_file         the output path where to write the properties, or
 #                            '-' for stdout.
+#  Verify command arguments:
+#  --payload             payload input file
+#  --source_image        verify payload to the specified source image.
+#  --target_image        the target image to verify upon.
 
 
 # Exit codes:
@@ -85,6 +102,7 @@
 for signing."
 HELP_SIGN="sign: Insert the signatures into the unsigned payload."
 HELP_PROPERTIES="properties: Extract payload properties to a file."
+HELP_VERIFY="verify: Verify a (signed) update payload."
 
 usage() {
   echo "Supported commands:"
@@ -93,6 +111,7 @@
   echo "${HELP_HASH}"
   echo "${HELP_SIGN}"
   echo "${HELP_PROPERTIES}"
+  echo "${HELP_VERIFY}"
   echo
   echo "Use: \"$0 <command> --help\" for more options."
 }
@@ -123,6 +142,11 @@
   properties)
     FLAGS_HELP="${HELP_PROPERTIES}"
     ;;
+
+  verify)
+    FLAGS_HELP="${HELP_VERIFY}"
+    ;;
+
   *)
     echo "Unrecognized command: \"${COMMAND}\"" >&2
     usage >&2
@@ -178,6 +202,15 @@
     "Path to output the extracted property files. If '-' is passed stdout will \
 be used."
 fi
+if [[ "${COMMAND}" == "verify" ]]; then
+  DEFINE_string payload "" \
+    "Path to the input payload file."
+  DEFINE_string target_image "" \
+    "Path to the target image to verify upon."
+  DEFINE_string source_image "" \
+    "Optional: Path to a source image. If specified, the delta update is \
+applied to this."
+fi
 
 DEFINE_string work_dir "${TMPDIR:-/tmp}" "Where to dump temporary files."
 
@@ -214,9 +247,6 @@
 # Path to the postinstall config file in target image if exists.
 POSTINSTALL_CONFIG_FILE=""
 
-# The fingerprint of zlib in the source image.
-ZLIB_FINGERPRINT=""
-
 # read_option_int <file.txt> <option_key> [default_value]
 #
 # Reads the unsigned integer value associated with |option_key| in a key=value
@@ -336,11 +366,6 @@
   # updater supports a newer major version.
   FORCE_MAJOR_VERSION="1"
 
-  if [[ "${partitions_array}" == "SRC_PARTITIONS" ]]; then
-    # Copy from zlib_fingerprint in source image to stdout.
-    ZLIB_FINGERPRINT=$(e2cp "${root}":/etc/zlib_fingerprint -)
-  fi
-
   # When generating legacy Chrome OS images, we need to use "boot" and "system"
   # for the partition names to be compatible with updating Brillo devices with
   # Chrome OS images.
@@ -376,7 +401,8 @@
     if grep -v -E '^[a-zA-Z0-9_-]*$' "${ab_partitions_list}" >&2; then
       die "Invalid partition names found in the partition list."
     fi
-    partitions=($(cat "${ab_partitions_list}"))
+    # Get partition list without duplicates.
+    partitions=($(awk '!seen[$0]++' "${ab_partitions_list}"))
     if [[ ${#partitions[@]} -eq 0 ]]; then
       die "The list of partitions is empty. Can't generate a payload."
     fi
@@ -414,10 +440,6 @@
 Disabling deltas for this source version."
       exit ${EX_UNSUPPORTED_DELTA}
     fi
-
-    if [[ "${FORCE_MINOR_VERSION}" -ge 4 ]]; then
-      ZLIB_FINGERPRINT=$(unzip -p "${image}" "META/zlib_fingerprint.txt")
-    fi
   else
     # Target image
     local postinstall_config=$(create_tempfile "postinstall_config.XXXXXX")
@@ -539,9 +561,6 @@
     if [[ -n "${FORCE_MINOR_VERSION}" ]]; then
       GENERATOR_ARGS+=( --minor_version="${FORCE_MINOR_VERSION}" )
     fi
-    if [[ -n "${ZLIB_FINGERPRINT}" ]]; then
-      GENERATOR_ARGS+=( --zlib_fingerprint="${ZLIB_FINGERPRINT}" )
-    fi
   fi
 
   if [[ -n "${FORCE_MAJOR_VERSION}" ]]; then
@@ -644,6 +663,91 @@
       -properties_file="${FLAGS_properties_file}"
 }
 
+validate_verify() {
+  [[ -n "${FLAGS_payload}" ]] ||
+    die "Error: you must specify an input filename with --payload FILENAME"
+
+  [[ -n "${FLAGS_target_image}" ]] ||
+    die "Error: you must specify a target image with --target_image FILENAME"
+}
+
+cmd_verify() {
+  local payload_type="delta"
+  if [[ -z "${FLAGS_source_image}" ]]; then
+    payload_type="full"
+  fi
+
+  echo "Extracting images for ${payload_type} update."
+
+  if [[ "${payload_type}" == "delta" ]]; then
+    extract_image "${FLAGS_source_image}" SRC_PARTITIONS
+  fi
+  extract_image "${FLAGS_target_image}" DST_PARTITIONS PARTITIONS_ORDER
+
+  declare -A TMP_PARTITIONS
+  for part in "${PARTITIONS_ORDER[@]}"; do
+    local tmp_part=$(create_tempfile "tmp_part.bin.XXXXXX")
+    echo "Creating temporary target partition ${tmp_part} for ${part}"
+    CLEANUP_FILES+=("${tmp_part}")
+    TMP_PARTITIONS[${part}]=${tmp_part}
+    local FILESIZE=$(stat -c%s "${DST_PARTITIONS[${part}]}")
+    echo "Truncating ${TMP_PARTITIONS[${part}]} to ${FILESIZE}"
+    truncate_file "${TMP_PARTITIONS[${part}]}" "${FILESIZE}"
+  done
+
+  echo "Verifying ${payload_type} update."
+  # Common payload args:
+  GENERATOR_ARGS=( -in_file="${FLAGS_payload}" )
+
+  local part old_partitions="" new_partitions="" partition_names=""
+  for part in "${PARTITIONS_ORDER[@]}"; do
+    if [[ -n "${partition_names}" ]]; then
+      partition_names+=":"
+      new_partitions+=":"
+      old_partitions+=":"
+    fi
+    partition_names+="${part}"
+    new_partitions+="${TMP_PARTITIONS[${part}]}"
+    old_partitions+="${SRC_PARTITIONS[${part}]:-}"
+  done
+
+  # Target image args:
+  GENERATOR_ARGS+=(
+    -partition_names="${partition_names}"
+    -new_partitions="${new_partitions}"
+  )
+
+  if [[ "${payload_type}" == "delta" ]]; then
+    # Source image args:
+    GENERATOR_ARGS+=(
+      -old_partitions="${old_partitions}"
+    )
+  fi
+
+  if [[ -n "${FORCE_MAJOR_VERSION}" ]]; then
+    GENERATOR_ARGS+=( --major_version="${FORCE_MAJOR_VERSION}" )
+  fi
+
+  echo "Running delta_generator to verify ${payload_type} payload with args: \
+${GENERATOR_ARGS[@]}"
+  "${GENERATOR}" "${GENERATOR_ARGS[@]}"
+
+  if [[ $? -eq 0 ]]; then
+    echo "Done applying ${payload_type} update."
+    echo "Checking the newly generated partitions against the target partitions"
+    for part in "${PARTITIONS_ORDER[@]}"; do
+      cmp "${TMP_PARTITIONS[${part}]}" "${DST_PARTITIONS[${part}]}"
+      local not_str=""
+      if [[ $? -ne 0 ]]; then
+        not_str="in"
+      fi
+      echo "The new partition (${part}) is ${not_str}valid."
+    done
+  else
+    echo "Failed to apply ${payload_type} update."
+  fi
+}
+
 # Sanity check that the real generator exists:
 GENERATOR="$(which delta_generator || true)"
 [[ -x "${GENERATOR}" ]] || die "can't find delta_generator"
@@ -661,4 +765,7 @@
   properties) validate_properties
               cmd_properties
               ;;
+  verify) validate_verify
+          cmd_verify
+          ;;
 esac
diff --git a/scripts/paycheck.py b/scripts/paycheck.py
index 0195f53..8df1bf0 100755
--- a/scripts/paycheck.py
+++ b/scripts/paycheck.py
@@ -12,7 +12,6 @@
 import os
 import sys
 
-# pylint: disable=F0401
 lib_dir = os.path.join(os.path.dirname(__file__), 'lib')
 if os.path.exists(lib_dir) and os.path.isdir(lib_dir):
   sys.path.insert(1, lib_dir)
@@ -91,6 +90,8 @@
                               'operations (not in-place)'))
   trace_opts.add_option('--bspatch-path', metavar='FILE',
                         help=('use the specified bspatch binary'))
+  trace_opts.add_option('--puffpatch-path', metavar='FILE',
+                        help=('use the specified puffpatch binary'))
   parser.add_option_group(trace_opts)
 
   trace_opts = optparse.OptionGroup(parser, 'Block tracing')
@@ -147,6 +148,8 @@
       parser.error('--extract-bsdiff can only be used when applying payloads')
     if opts.bspatch_path:
       parser.error('--bspatch-path can only be used when applying payloads')
+    if opts.puffpatch_path:
+      parser.error('--puffpatch-path can only be used when applying payloads')
   else:
     parser.error('unexpected number of arguments')
 
@@ -215,6 +218,8 @@
         dargs = {'bsdiff_in_place': not options.extract_bsdiff}
         if options.bspatch_path:
           dargs['bspatch_path'] = options.bspatch_path
+        if options.puffpatch_path:
+          dargs['puffpatch_path'] = options.puffpatch_path
         if options.assert_type == _TYPE_DELTA:
           dargs['old_kernel_part'] = extra_args[2]
           dargs['old_rootfs_part'] = extra_args[3]
diff --git a/scripts/run_unittests b/scripts/run_unittests
new file mode 100755
index 0000000..c8e713d
--- /dev/null
+++ b/scripts/run_unittests
@@ -0,0 +1,28 @@
+#!/bin/bash
+#
+# Copyright 2018 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# Runs update_payload unittests
+
+set -e
+
+# Invoke unittest scripts.
+for unittest_script in update_payload/*_unittest.py; do
+  filename=$(basename "${unittest_script}")
+  python -m update_payload."${filename%.*}"
+done
+
+exit 0
diff --git a/scripts/update_device.py b/scripts/update_device.py
index 75c58a7..64cfbe3 100755
--- a/scripts/update_device.py
+++ b/scripts/update_device.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/python2
 #
 # Copyright (C) 2017 The Android Open Source Project
 #
@@ -19,18 +19,27 @@
 
 import argparse
 import BaseHTTPServer
+import hashlib
 import logging
 import os
 import socket
 import subprocess
 import sys
 import threading
+import xml.etree.ElementTree
 import zipfile
 
+import update_payload.payload
+
 
 # The path used to store the OTA package when applying the package from a file.
 OTA_PACKAGE_PATH = '/data/ota_package'
 
+# The path to the payload public key on the device.
+PAYLOAD_KEY_PATH = '/etc/update_engine/update-payload-key.pub.pem'
+
+# The port on the device that update_engine should connect to.
+DEVICE_PORT = 1234
 
 def CopyFileObjLength(fsrc, fdst, buffer_size=128 * 1024, copy_length=None):
   """Copy from a file object to another.
@@ -90,10 +99,11 @@
 
   Attributes:
     serving_payload: path to the only payload file we are serving.
+    serving_range: the start offset and size tuple of the payload.
   """
 
   @staticmethod
-  def _ParseRange(range_str, file_size):
+  def _parse_range(range_str, file_size):
     """Parse an HTTP range string.
 
     Args:
@@ -140,12 +150,12 @@
     else:
       self.send_response(200)
 
-    stat = os.fstat(f.fileno())
-    start_range, end_range = self._ParseRange(self.headers.get('range'),
-                                              stat.st_size)
+    serving_start, serving_size = self.serving_range
+    start_range, end_range = self._parse_range(self.headers.get('range'),
+                                               serving_size)
     logging.info('Serving request for %s from %s [%d, %d) length: %d',
-             self.path, self.serving_payload, start_range, end_range,
-             end_range - start_range)
+                 self.path, self.serving_payload, serving_start + start_range,
+                 serving_start + end_range, end_range - start_range)
 
     self.send_header('Accept-Ranges', 'bytes')
     self.send_header('Content-Range',
@@ -153,22 +163,99 @@
                      '/' + str(end_range - start_range))
     self.send_header('Content-Length', end_range - start_range)
 
+    stat = os.fstat(f.fileno())
     self.send_header('Last-Modified', self.date_time_string(stat.st_mtime))
     self.send_header('Content-type', 'application/octet-stream')
     self.end_headers()
 
-    f.seek(start_range)
+    f.seek(serving_start + start_range)
     CopyFileObjLength(f, self.wfile, copy_length=end_range - start_range)
 
 
+  def do_POST(self):  # pylint: disable=invalid-name
+    """Reply with the omaha response xml."""
+    if self.path != '/update':
+      self.send_error(404, 'Unknown request')
+      return
+
+    if not self.serving_payload:
+      self.send_error(500, 'No serving payload set')
+      return
+
+    try:
+      f = open(self.serving_payload, 'rb')
+    except IOError:
+      self.send_error(404, 'File not found')
+      return
+
+    content_length = int(self.headers.getheader('Content-Length'))
+    request_xml = self.rfile.read(content_length)
+    xml_root = xml.etree.ElementTree.fromstring(request_xml)
+    appid = None
+    for app in xml_root.iter('app'):
+      if 'appid' in app.attrib:
+        appid = app.attrib['appid']
+        break
+    if not appid:
+      self.send_error(400, 'No appid in Omaha request')
+      return
+
+    self.send_response(200)
+    self.send_header("Content-type", "text/xml")
+    self.end_headers()
+
+    serving_start, serving_size = self.serving_range
+    sha256 = hashlib.sha256()
+    f.seek(serving_start)
+    bytes_to_hash = serving_size
+    while bytes_to_hash:
+      buf = f.read(min(bytes_to_hash, 1024 * 1024))
+      if not buf:
+        self.send_error(500, 'Payload too small')
+        return
+      sha256.update(buf)
+      bytes_to_hash -= len(buf)
+
+    payload = update_payload.Payload(f, payload_file_offset=serving_start)
+    payload.Init()
+
+    response_xml = '''
+        <?xml version="1.0" encoding="UTF-8"?>
+        <response protocol="3.0">
+          <app appid="{appid}">
+            <updatecheck status="ok">
+              <urls>
+                <url codebase="http://127.0.0.1:{port}/"/>
+              </urls>
+              <manifest version="0.0.0.1">
+                <actions>
+                  <action event="install" run="payload"/>
+                  <action event="postinstall" MetadataSize="{metadata_size}"/>
+                </actions>
+                <packages>
+                  <package hash_sha256="{payload_hash}" name="payload" size="{payload_size}"/>
+                </packages>
+              </manifest>
+            </updatecheck>
+          </app>
+        </response>
+    '''.format(appid=appid, port=DEVICE_PORT,
+               metadata_size=payload.metadata_size,
+               payload_hash=sha256.hexdigest(),
+               payload_size=serving_size)
+    self.wfile.write(response_xml.strip())
+    return
+
+
 class ServerThread(threading.Thread):
   """A thread for serving HTTP requests."""
 
-  def __init__(self, ota_filename):
+  def __init__(self, ota_filename, serving_range):
     threading.Thread.__init__(self)
-    # serving_payload is a class attribute and the UpdateHandler class is
-    # instantiated with every request.
+    # serving_payload and serving_range are class attributes and the
+    # UpdateHandler class is instantiated with every request.
     UpdateHandler.serving_payload = ota_filename
+    UpdateHandler.serving_range = serving_range
     self._httpd = BaseHTTPServer.HTTPServer(('127.0.0.1', 0), UpdateHandler)
     self.port = self._httpd.server_port
 
@@ -183,26 +270,31 @@
     self._httpd.socket.close()
 
 
-def StartServer(ota_filename):
-  t = ServerThread(ota_filename)
+def StartServer(ota_filename, serving_range):
+  t = ServerThread(ota_filename, serving_range)
   t.start()
   return t
 
 
-def AndroidUpdateCommand(ota_filename, payload_url):
+def AndroidUpdateCommand(ota_filename, payload_url, extra_headers):
   """Return the command to run to start the update in the Android device."""
   ota = AndroidOTAPackage(ota_filename)
   headers = ota.properties
   headers += 'USER_AGENT=Dalvik (something, something)\n'
-
-  # headers += 'POWERWASH=1\n'
   headers += 'NETWORK_ID=0\n'
+  headers += extra_headers
 
   return ['update_engine_client', '--update', '--follow',
           '--payload=%s' % payload_url, '--offset=%d' % ota.offset,
           '--size=%d' % ota.size, '--headers="%s"' % headers]
 
 
+def OmahaUpdateCommand(omaha_url):
+  """Return the command to run to start the update in a device using Omaha."""
+  return ['update_engine_client', '--update', '--follow',
+          '--omaha_url=%s' % omaha_url]
+
+
 class AdbHost(object):
   """Represents a device connected via ADB."""
 
@@ -235,11 +327,28 @@
     p.wait()
     return p.returncode
 
+  def adb_output(self, command):
+    """Run an ADB command like "adb push" and return the output.
+
+    Args:
+      command: list of strings containing command and arguments to run
+
+    Returns:
+      the program's output as a string.
+
+    Raises:
+      subprocess.CalledProcessError on command exit != 0.
+    """
+    command = self._command_prefix + command
+    logging.info('Running: %s', ' '.join(str(x) for x in command))
+    return subprocess.check_output(command, universal_newlines=True)
+
 
 def main():
   parser = argparse.ArgumentParser(description='Android A/B OTA helper.')
-  parser.add_argument('otafile', metavar='ZIP', type=str,
-                      help='the OTA package file (a .zip file).')
+  parser.add_argument('otafile', metavar='PAYLOAD', type=str,
+                      help='the OTA package file (a .zip file) or raw payload \
+                      if device uses Omaha.')
   parser.add_argument('--file', action='store_true',
                       help='Push the file to the device before updating.')
   parser.add_argument('--no-push', action='store_true',
@@ -248,6 +357,10 @@
                       help='The specific device to use.')
   parser.add_argument('--no-verbose', action='store_true',
                       help='Less verbose output')
+  parser.add_argument('--public-key', type=str, default='',
+                      help='Override the public key used to verify payload.')
+  parser.add_argument('--extra-headers', type=str, default='',
+                      help='Extra headers to pass to the device.')
   args = parser.parse_args()
   logging.basicConfig(
       level=logging.WARNING if args.no_verbose else logging.INFO)
@@ -262,27 +375,57 @@
   # List of commands to perform the update.
   cmds = []
 
+  help_cmd = ['shell', 'su', '0', 'update_engine_client', '--help']
+  use_omaha = 'omaha' in dut.adb_output(help_cmd)
+
   if args.file:
     # Update via pushing a file to /data.
     device_ota_file = os.path.join(OTA_PACKAGE_PATH, 'debug.zip')
     payload_url = 'file://' + device_ota_file
     if not args.no_push:
-      cmds.append(['push', args.otafile, device_ota_file])
+      data_local_tmp_file = '/data/local/tmp/debug.zip'
+      cmds.append(['push', args.otafile, data_local_tmp_file])
+      cmds.append(['shell', 'su', '0', 'mv', data_local_tmp_file,
+                   device_ota_file])
+      cmds.append(['shell', 'su', '0', 'chcon',
+                   'u:object_r:ota_package_file:s0', device_ota_file])
     cmds.append(['shell', 'su', '0', 'chown', 'system:cache', device_ota_file])
     cmds.append(['shell', 'su', '0', 'chmod', '0660', device_ota_file])
   else:
     # Update via sending the payload over the network with an "adb reverse"
     # command.
-    device_port = 1234
-    payload_url = 'http://127.0.0.1:%d/payload' % device_port
-    server_thread = StartServer(args.otafile)
+    payload_url = 'http://127.0.0.1:%d/payload' % DEVICE_PORT
+    if use_omaha and zipfile.is_zipfile(args.otafile):
+      ota = AndroidOTAPackage(args.otafile)
+      serving_range = (ota.offset, ota.size)
+    else:
+      serving_range = (0, os.stat(args.otafile).st_size)
+    server_thread = StartServer(args.otafile, serving_range)
     cmds.append(
-        ['reverse', 'tcp:%d' % device_port, 'tcp:%d' % server_thread.port])
-    finalize_cmds.append(['reverse', '--remove', 'tcp:%d' % device_port])
+        ['reverse', 'tcp:%d' % DEVICE_PORT, 'tcp:%d' % server_thread.port])
+    finalize_cmds.append(['reverse', '--remove', 'tcp:%d' % DEVICE_PORT])
+
+  if args.public_key:
+    payload_key_dir = os.path.dirname(PAYLOAD_KEY_PATH)
+    cmds.append(
+        ['shell', 'su', '0', 'mount', '-t', 'tmpfs', 'tmpfs', payload_key_dir])
+    # Allow adb push to payload_key_dir
+    cmds.append(['shell', 'su', '0', 'chcon', 'u:object_r:shell_data_file:s0',
+                 payload_key_dir])
+    cmds.append(['push', args.public_key, PAYLOAD_KEY_PATH])
+    # Allow update_engine to read it.
+    cmds.append(['shell', 'su', '0', 'chcon', '-R', 'u:object_r:system_file:s0',
+                 payload_key_dir])
+    finalize_cmds.append(['shell', 'su', '0', 'umount', payload_key_dir])
 
   try:
     # The main update command using the configured payload_url.
-    update_cmd = AndroidUpdateCommand(args.otafile, payload_url)
+    if use_omaha:
+      update_cmd = \
+          OmahaUpdateCommand('http://127.0.0.1:%d/update' % DEVICE_PORT)
+    else:
+      update_cmd = \
+          AndroidUpdateCommand(args.otafile, payload_url, args.extra_headers)
     cmds.append(['shell', 'su', '0'] + update_cmd)
 
     for cmd in cmds:
diff --git a/scripts/update_payload/__init__.py b/scripts/update_payload/__init__.py
index 1906a16..e4a5588 100644
--- a/scripts/update_payload/__init__.py
+++ b/scripts/update_payload/__init__.py
@@ -5,7 +5,6 @@
 """Library for processing, verifying and applying Chrome OS update payloads."""
 
 # Just raise the interface classes to the root namespace.
-# pylint: disable=W0401
-from checker import CHECKS_TO_DISABLE
-from error import PayloadError
-from payload import Payload
+from update_payload.checker import CHECKS_TO_DISABLE
+from update_payload.error import PayloadError
+from update_payload.payload import Payload
diff --git a/scripts/update_payload/applier.py b/scripts/update_payload/applier.py
index e3708c7..e470ac4 100644
--- a/scripts/update_payload/applier.py
+++ b/scripts/update_payload/applier.py
@@ -24,8 +24,8 @@
 import sys
 import tempfile
 
-import common
-from error import PayloadError
+from update_payload import common
+from update_payload.error import PayloadError
 
 
 #
@@ -44,7 +44,6 @@
     PayloadError if computed hash doesn't match expected one, or if fails to
     read the specified length of data.
   """
-  # pylint: disable=E1101
   hasher = hashlib.sha256()
   block_length = 1024 * 1024
   max_length = length if length >= 0 else sys.maxint
@@ -195,14 +194,14 @@
   """
 
   def __init__(self, payload, bsdiff_in_place=True, bspatch_path=None,
-               imgpatch_path=None, truncate_to_expected_size=True):
+               puffpatch_path=None, truncate_to_expected_size=True):
     """Initialize the applier.
 
     Args:
       payload: the payload object to check
       bsdiff_in_place: whether to perform BSDIFF operation in-place (optional)
       bspatch_path: path to the bspatch binary (optional)
-      imgpatch_path: path to the imgpatch binary (optional)
+      puffpatch_path: path to the puffpatch binary (optional)
       truncate_to_expected_size: whether to truncate the resulting partitions
                                  to their expected sizes, as specified in the
                                  payload (optional)
@@ -213,7 +212,7 @@
     self.minor_version = payload.manifest.minor_version
     self.bsdiff_in_place = bsdiff_in_place
     self.bspatch_path = bspatch_path or 'bspatch'
-    self.imgpatch_path = imgpatch_path or 'imgpatch'
+    self.puffpatch_path = puffpatch_path or 'puffin'
     self.truncate_to_expected_size = truncate_to_expected_size
 
   def _ApplyReplaceOperation(self, op, op_name, out_data, part_file, part_size):
@@ -301,22 +300,27 @@
     _WriteExtents(part_file, in_data, op.dst_extents, block_size,
                   '%s.dst_extents' % op_name)
 
-  def _ApplyBsdiffOperation(self, op, op_name, patch_data, new_part_file):
-    """Applies a BSDIFF operation.
+  def _ApplyZeroOperation(self, op, op_name, part_file):
+    """Applies a ZERO operation.
 
     Args:
       op: the operation object
       op_name: name string for error reporting
-      patch_data: the binary patch content
-      new_part_file: the target partition file object
+      part_file: the partition file object
 
     Raises:
       PayloadError if something goes wrong.
     """
-    # Implemented using a SOURCE_BSDIFF operation with the source and target
-    # partition set to the new partition.
-    self._ApplyDiffOperation(op, op_name, patch_data, new_part_file,
-                             new_part_file)
+    block_size = self.block_size
+    base_name = '%s.dst_extents' % op_name
+
+    # Iterate over the extents and write zero.
+    # pylint: disable=unused-variable
+    for ex, ex_name in common.ExtentIter(op.dst_extents, base_name):
+      # Only do actual writing if this is not a pseudo-extent.
+      if ex.start_block != common.PSEUDO_EXTENT_MARKER:
+        part_file.seek(ex.start_block * block_size)
+        part_file.write('\0' * (ex.num_blocks * block_size))
 
   def _ApplySourceCopyOperation(self, op, op_name, old_part_file,
                                 new_part_file):
@@ -345,9 +349,26 @@
     _WriteExtents(new_part_file, in_data, op.dst_extents, block_size,
                   '%s.dst_extents' % op_name)
 
+  def _BytesInExtents(self, extents, base_name):
+    """Counts the length of extents in bytes.
+
+    Args:
+      extents: The list of Extents.
+      base_name: For error reporting.
+
+    Returns:
+      The number of bytes in extents.
+    """
+
+    length = 0
+    # pylint: disable=unused-variable
+    for ex, ex_name in common.ExtentIter(extents, base_name):
+      length += ex.num_blocks * self.block_size
+    return length
+
   def _ApplyDiffOperation(self, op, op_name, patch_data, old_part_file,
                           new_part_file):
-    """Applies a SOURCE_BSDIFF or IMGDIFF operation.
+    """Applies a SOURCE_BSDIFF, BROTLI_BSDIFF or PUFFDIFF operation.
 
     Args:
       op: the operation object
@@ -372,24 +393,40 @@
       patch_file.write(patch_data)
 
     if (hasattr(new_part_file, 'fileno') and
-        ((not old_part_file) or hasattr(old_part_file, 'fileno')) and
-        op.type != common.OpType.IMGDIFF):
+        ((not old_part_file) or hasattr(old_part_file, 'fileno'))):
       # Construct input and output extents argument for bspatch.
+
       in_extents_arg, _, _ = _ExtentsToBspatchArg(
           op.src_extents, block_size, '%s.src_extents' % op_name,
-          data_length=op.src_length)
+          data_length=op.src_length if op.src_length else
+          self._BytesInExtents(op.src_extents, "%s.src_extents"))
       out_extents_arg, pad_off, pad_len = _ExtentsToBspatchArg(
           op.dst_extents, block_size, '%s.dst_extents' % op_name,
-          data_length=op.dst_length)
+          data_length=op.dst_length if op.dst_length else
+          self._BytesInExtents(op.dst_extents, "%s.dst_extents"))
 
       new_file_name = '/dev/fd/%d' % new_part_file.fileno()
       # Diff from source partition.
       old_file_name = '/dev/fd/%d' % old_part_file.fileno()
 
-      # Invoke bspatch on partition file with extents args.
-      bspatch_cmd = [self.bspatch_path, old_file_name, new_file_name,
-                     patch_file_name, in_extents_arg, out_extents_arg]
-      subprocess.check_call(bspatch_cmd)
+      if op.type in (common.OpType.BSDIFF, common.OpType.SOURCE_BSDIFF,
+                     common.OpType.BROTLI_BSDIFF):
+        # Invoke bspatch on partition file with extents args.
+        bspatch_cmd = [self.bspatch_path, old_file_name, new_file_name,
+                       patch_file_name, in_extents_arg, out_extents_arg]
+        subprocess.check_call(bspatch_cmd)
+      elif op.type == common.OpType.PUFFDIFF:
+        # Invoke puffpatch on partition file with extents args.
+        puffpatch_cmd = [self.puffpatch_path,
+                         "--operation=puffpatch",
+                         "--src_file=%s" % old_file_name,
+                         "--dst_file=%s" % new_file_name,
+                         "--patch_file=%s" % patch_file_name,
+                         "--src_extents=%s" % in_extents_arg,
+                         "--dst_extents=%s" % out_extents_arg]
+        subprocess.check_call(puffpatch_cmd)
+      else:
+        raise PayloadError("Unknown operation %s", op.type)
 
       # Pad with zeros past the total output length.
       if pad_len:
@@ -399,7 +436,9 @@
       # Gather input raw data and write to a temp file.
       input_part_file = old_part_file if old_part_file else new_part_file
       in_data = _ReadExtents(input_part_file, op.src_extents, block_size,
-                             max_length=op.src_length)
+                             max_length=op.src_length if op.src_length else
+                             self._BytesInExtents(op.src_extents,
+                                                  "%s.src_extents"))
       with tempfile.NamedTemporaryFile(delete=False) as in_file:
         in_file_name = in_file.name
         in_file.write(in_data)
@@ -408,12 +447,22 @@
       with tempfile.NamedTemporaryFile(delete=False) as out_file:
         out_file_name = out_file.name
 
-      # Invoke bspatch.
-      patch_cmd = [self.bspatch_path, in_file_name, out_file_name,
-                   patch_file_name]
-      if op.type == common.OpType.IMGDIFF:
-        patch_cmd[0] = self.imgpatch_path
-      subprocess.check_call(patch_cmd)
+      if op.type in (common.OpType.BSDIFF, common.OpType.SOURCE_BSDIFF,
+                     common.OpType.BROTLI_BSDIFF):
+        # Invoke bspatch.
+        bspatch_cmd = [self.bspatch_path, in_file_name, out_file_name,
+                       patch_file_name]
+        subprocess.check_call(bspatch_cmd)
+      elif op.type == common.OpType.PUFFDIFF:
+        # Invoke puffpatch.
+        puffpatch_cmd = [self.puffpatch_path,
+                         "--operation=puffpatch",
+                         "--src_file=%s" % in_file_name,
+                         "--dst_file=%s" % out_file_name,
+                         "--patch_file=%s" % patch_file_name]
+        subprocess.check_call(puffpatch_cmd)
+      else:
+        raise PayloadError("Unknown operation %s", op.type)
 
       # Read output.
       with open(out_file_name, 'rb') as out_file:
@@ -463,12 +512,16 @@
         self._ApplyReplaceOperation(op, op_name, data, new_part_file, part_size)
       elif op.type == common.OpType.MOVE:
         self._ApplyMoveOperation(op, op_name, new_part_file)
+      elif op.type == common.OpType.ZERO:
+        self._ApplyZeroOperation(op, op_name, new_part_file)
       elif op.type == common.OpType.BSDIFF:
-        self._ApplyBsdiffOperation(op, op_name, data, new_part_file)
+        self._ApplyDiffOperation(op, op_name, data, new_part_file,
+                                 new_part_file)
       elif op.type == common.OpType.SOURCE_COPY:
         self._ApplySourceCopyOperation(op, op_name, old_part_file,
                                        new_part_file)
-      elif op.type in (common.OpType.SOURCE_BSDIFF, common.OpType.IMGDIFF):
+      elif op.type in (common.OpType.SOURCE_BSDIFF, common.OpType.PUFFDIFF,
+                       common.OpType.BROTLI_BSDIFF):
         self._ApplyDiffOperation(op, op_name, data, old_part_file,
                                  new_part_file)
       else:
@@ -504,7 +557,7 @@
         shutil.copyfile(old_part_file_name, new_part_file_name)
       elif (self.minor_version == common.SOURCE_MINOR_PAYLOAD_VERSION or
             self.minor_version == common.OPSRCHASH_MINOR_PAYLOAD_VERSION or
-            self.minor_version == common.IMGDIFF_MINOR_PAYLOAD_VERSION):
+            self.minor_version == common.PUFFDIFF_MINOR_PAYLOAD_VERSION):
         # In minor version >= 2, we don't want to copy the partitions, so
         # instead just make the new partition file.
         open(new_part_file_name, 'w').close()
diff --git a/scripts/update_payload/block_tracer.py b/scripts/update_payload/block_tracer.py
index f222b21..5caf7e3 100644
--- a/scripts/update_payload/block_tracer.py
+++ b/scripts/update_payload/block_tracer.py
@@ -16,7 +16,7 @@
 
 from __future__ import print_function
 
-import common
+from update_payload import common
 
 
 #
diff --git a/scripts/update_payload/checker.py b/scripts/update_payload/checker.py
index e13ea13..e4cb845 100644
--- a/scripts/update_payload/checker.py
+++ b/scripts/update_payload/checker.py
@@ -21,11 +21,11 @@
 import os
 import subprocess
 
-import common
-import error
-import format_utils
-import histogram
-import update_metadata_pb2
+from update_payload import common
+from update_payload import error
+from update_payload import format_utils
+from update_payload import histogram
+from update_payload import update_metadata_pb2
 
 
 #
@@ -815,10 +815,30 @@
     if dst_extent:
       raise error.PayloadError('%s: excess dst blocks.' % op_name)
 
-  def _CheckAnyDiffOperation(self, data_length, total_dst_blocks, op_name):
-    """Specific checks for BSDIFF, SOURCE_BSDIFF and IMGDIFF operations.
+  def _CheckZeroOperation(self, op, op_name):
+    """Specific checks for ZERO operations.
 
     Args:
+      op: The operation object from the manifest.
+      op_name: Operation name for error reporting.
+
+    Raises:
+      error.PayloadError if any check fails.
+    """
+    # Check: Does not contain src extents, data_length and data_offset.
+    if op.src_extents:
+      raise error.PayloadError('%s: contains src_extents.' % op_name)
+    if op.data_length:
+      raise error.PayloadError('%s: contains data_length.' % op_name)
+    if op.data_offset:
+      raise error.PayloadError('%s: contains data_offset.' % op_name)
+
+  def _CheckAnyDiffOperation(self, op, data_length, total_dst_blocks, op_name):
+    """Specific checks for BSDIFF, SOURCE_BSDIFF, PUFFDIFF and BROTLI_BSDIFF
+       operations.
+
+    Args:
+      op: The operation.
       data_length: The length of the data blob associated with the operation.
       total_dst_blocks: Total number of blocks in dst_extents.
       op_name: Operation name for error reporting.
@@ -838,6 +858,15 @@
           (op_name, data_length, total_dst_blocks, self.block_size,
            total_dst_blocks * self.block_size))
 
+    # Check the existence of src_length and dst_length for legacy bsdiffs.
+    if (op.type == common.OpType.BSDIFF or
+        (op.type == common.OpType.SOURCE_BSDIFF and self.minor_version <= 3)):
+      if not op.HasField('src_length') or not op.HasField('dst_length'):
+        raise error.PayloadError('%s: require {src,dst}_length.' % op_name)
+    else:
+      if op.HasField('src_length') or op.HasField('dst_length'):
+        raise error.PayloadError('%s: unneeded {src,dst}_length.' % op_name)
+
   def _CheckSourceCopyOperation(self, data_offset, total_src_blocks,
                                 total_dst_blocks, op_name):
     """Specific checks for SOURCE_COPY.
@@ -941,8 +970,6 @@
             op_name)
 
       # Check: Hash verifies correctly.
-      # pylint cannot find the method in hashlib, for some reason.
-      # pylint: disable=E1101
       actual_hash = hashlib.sha256(self.payload.ReadDataBlob(data_offset,
                                                              data_length))
       if op.data_sha256_hash != actual_hash.digest():
@@ -972,17 +999,20 @@
     elif op.type == common.OpType.MOVE and self.minor_version == 1:
       self._CheckMoveOperation(op, data_offset, total_src_blocks,
                                total_dst_blocks, op_name)
+    elif op.type == common.OpType.ZERO and self.minor_version >= 4:
+      self._CheckZeroOperation(op, op_name)
     elif op.type == common.OpType.BSDIFF and self.minor_version == 1:
-      self._CheckAnyDiffOperation(data_length, total_dst_blocks, op_name)
+      self._CheckAnyDiffOperation(op, data_length, total_dst_blocks, op_name)
     elif op.type == common.OpType.SOURCE_COPY and self.minor_version >= 2:
       self._CheckSourceCopyOperation(data_offset, total_src_blocks,
                                      total_dst_blocks, op_name)
       self._CheckAnySourceOperation(op, total_src_blocks, op_name)
     elif op.type == common.OpType.SOURCE_BSDIFF and self.minor_version >= 2:
-      self._CheckAnyDiffOperation(data_length, total_dst_blocks, op_name)
+      self._CheckAnyDiffOperation(op, data_length, total_dst_blocks, op_name)
       self._CheckAnySourceOperation(op, total_src_blocks, op_name)
-    elif op.type == common.OpType.IMGDIFF and self.minor_version >= 4:
-      self._CheckAnyDiffOperation(data_length, total_dst_blocks, op_name)
+    elif (op.type in (common.OpType.PUFFDIFF, common.OpType.BROTLI_BSDIFF) and
+          self.minor_version >= 4):
+      self._CheckAnyDiffOperation(op, data_length, total_dst_blocks, op_name)
       self._CheckAnySourceOperation(op, total_src_blocks, op_name)
     else:
       raise error.PayloadError(
@@ -1011,8 +1041,8 @@
                        itertools.repeat(0, self._SizeToNumBlocks(total_size)))
 
   def _CheckOperations(self, operations, report, base_name, old_fs_size,
-                       new_fs_size, new_usable_size, prev_data_offset,
-                       allow_signature):
+                       new_fs_size, old_usable_size, new_usable_size,
+                       prev_data_offset, allow_signature):
     """Checks a sequence of update operations.
 
     Args:
@@ -1021,6 +1051,7 @@
       base_name: The name of the operation block.
       old_fs_size: The old filesystem size in bytes.
       new_fs_size: The new filesystem size in bytes.
+      old_usable_size: The overall usable size of the old partition in bytes.
       new_usable_size: The overall usable size of the new partition in bytes.
       prev_data_offset: Offset of last used data bytes.
       allow_signature: Whether this sequence may contain signature operations.
@@ -1038,10 +1069,12 @@
         common.OpType.REPLACE: 0,
         common.OpType.REPLACE_BZ: 0,
         common.OpType.MOVE: 0,
+        common.OpType.ZERO: 0,
         common.OpType.BSDIFF: 0,
         common.OpType.SOURCE_COPY: 0,
         common.OpType.SOURCE_BSDIFF: 0,
-        common.OpType.IMGDIFF: 0,
+        common.OpType.PUFFDIFF: 0,
+        common.OpType.BROTLI_BSDIFF: 0,
     }
     # Total blob sizes for each operation type.
     op_blob_totals = {
@@ -1051,7 +1084,8 @@
         common.OpType.BSDIFF: 0,
         # SOURCE_COPY operations don't have blobs.
         common.OpType.SOURCE_BSDIFF: 0,
-        common.OpType.IMGDIFF: 0,
+        common.OpType.PUFFDIFF: 0,
+        common.OpType.BROTLI_BSDIFF: 0,
     }
     # Counts of hashed vs unhashed operations.
     blob_hash_counts = {
@@ -1062,7 +1096,7 @@
       blob_hash_counts['signature'] = 0
 
     # Allocate old and new block counters.
-    old_block_counters = (self._AllocBlockCounters(new_usable_size)
+    old_block_counters = (self._AllocBlockCounters(old_usable_size)
                           if old_fs_size else None)
     new_block_counters = self._AllocBlockCounters(new_usable_size)
 
@@ -1079,7 +1113,7 @@
       is_last = op_num == len(operations)
       curr_data_used = self._CheckOperation(
           op, op_name, is_last, old_block_counters, new_block_counters,
-          new_usable_size if old_fs_size else 0, new_usable_size,
+          old_usable_size, new_usable_size,
           prev_data_offset + total_data_used, allow_signature,
           blob_hash_counts)
       if curr_data_used:
@@ -1132,8 +1166,6 @@
     report.AddSection('signatures')
 
     # Check: At least one signature present.
-    # pylint cannot see through the protobuf object, it seems.
-    # pylint: disable=E1101
     if not sigs.signatures:
       raise error.PayloadError('Signature block is empty.')
 
@@ -1229,10 +1261,13 @@
       #   exceed the filesystem size when moving data blocks around.
       # - Otherwise, use the encoded filesystem size.
       new_rootfs_usable_size = self.new_rootfs_fs_size
+      old_rootfs_usable_size = self.old_rootfs_fs_size
       if rootfs_part_size:
         new_rootfs_usable_size = rootfs_part_size
+        old_rootfs_usable_size = rootfs_part_size
       elif self.payload_type == _TYPE_DELTA and self.minor_version in (None, 1):
         new_rootfs_usable_size = _OLD_DELTA_USABLE_PART_SIZE
+        old_rootfs_usable_size = _OLD_DELTA_USABLE_PART_SIZE
 
       # Part 3: Examine rootfs operations.
       # TODO(garnold)(chromium:243559) only default to the filesystem size if
@@ -1242,7 +1277,8 @@
       total_blob_size = self._CheckOperations(
           self.payload.manifest.install_operations, report,
           'install_operations', self.old_rootfs_fs_size,
-          self.new_rootfs_fs_size, new_rootfs_usable_size, 0, False)
+          self.new_rootfs_fs_size, old_rootfs_usable_size,
+          new_rootfs_usable_size, 0, False)
 
       # Part 4: Examine kernel operations.
       # TODO(garnold)(chromium:243559) as above.
@@ -1251,6 +1287,7 @@
           self.payload.manifest.kernel_install_operations, report,
           'kernel_install_operations', self.old_kernel_fs_size,
           self.new_kernel_fs_size,
+          kernel_part_size if kernel_part_size else self.old_kernel_fs_size,
           kernel_part_size if kernel_part_size else self.new_kernel_fs_size,
           total_blob_size, True)
 
diff --git a/scripts/update_payload/checker_unittest.py b/scripts/update_payload/checker_unittest.py
index 56b1a30..974519d 100755
--- a/scripts/update_payload/checker_unittest.py
+++ b/scripts/update_payload/checker_unittest.py
@@ -20,14 +20,16 @@
 # pylint: disable=F0401
 import mox
 
-import checker
-import common
-import payload as update_payload  # Avoid name conflicts later.
-import test_utils
-import update_metadata_pb2
+from update_payload import checker
+from update_payload import common
+from update_payload import test_utils
+from update_payload import update_metadata_pb2
+from update_payload.error import PayloadError
+from update_payload.payload import Payload # Avoid name conflicts later.
 
 
 def _OpTypeByName(op_name):
+  """Returns the type of an operation from itsname."""
   op_name_to_type = {
       'REPLACE': common.OpType.REPLACE,
       'REPLACE_BZ': common.OpType.REPLACE_BZ,
@@ -38,7 +40,8 @@
       'ZERO': common.OpType.ZERO,
       'DISCARD': common.OpType.DISCARD,
       'REPLACE_XZ': common.OpType.REPLACE_XZ,
-      'IMGDIFF': common.OpType.IMGDIFF,
+      'PUFFDIFF': common.OpType.PUFFDIFF,
+      'BROTLI_BSDIFF': common.OpType.BROTLI_BSDIFF,
   }
   return op_name_to_type[op_name]
 
@@ -54,7 +57,7 @@
   payload_file = cStringIO.StringIO()
   payload_gen_write_to_file_func(payload_file, **payload_gen_dargs)
   payload_file.seek(0)
-  payload = update_payload.Payload(payload_file)
+  payload = Payload(payload_file)
   payload.Init()
   return checker.PayloadChecker(payload, **checker_init_dargs)
 
@@ -64,7 +67,7 @@
   payload_file = cStringIO.StringIO()
   payload_gen.WriteToFile(payload_file)
   payload_file.seek(0)
-  payload = update_payload.Payload(payload_file)
+  payload = Payload(payload_file)
   payload.Init()
   return checker.PayloadChecker(payload)
 
@@ -90,7 +93,7 @@
 
   def MockPayload(self):
     """Create a mock payload object, complete with a mock manifest."""
-    payload = self.mox.CreateMock(update_payload.Payload)
+    payload = self.mox.CreateMock(Payload)
     payload.is_init = True
     payload.manifest = self.mox.CreateMock(
         update_metadata_pb2.DeltaArchiveManifest)
@@ -194,7 +197,7 @@
     args = (msg, name, report, is_mandatory, is_submsg)
     kwargs = {'convert': convert, 'linebreak': linebreak, 'indent': indent}
     if is_mandatory and not is_present:
-      self.assertRaises(update_payload.PayloadError,
+      self.assertRaises(PayloadError,
                         checker.PayloadChecker._CheckElem, *args, **kwargs)
     else:
       ret_val, ret_subreport = checker.PayloadChecker._CheckElem(*args,
@@ -228,8 +231,7 @@
 
     # Test the method call.
     if is_mandatory and not is_present:
-      self.assertRaises(update_payload.PayloadError, tested_func, *args,
-                        **kwargs)
+      self.assertRaises(PayloadError, tested_func, *args, **kwargs)
     else:
       ret_val = tested_func(*args, **kwargs)
       self.assertEquals(val if is_present else None, ret_val)
@@ -253,7 +255,7 @@
 
     # Test the method call.
     if is_mandatory and not is_present:
-      self.assertRaises(update_payload.PayloadError, tested_func, *args)
+      self.assertRaises(PayloadError, tested_func, *args)
     else:
       ret_val, ret_subreport = tested_func(*args)
       self.assertEquals(val if is_present else None, ret_val)
@@ -265,11 +267,9 @@
         None, None, 'foo', 'bar', 'baz'))
     self.assertIsNone(checker.PayloadChecker._CheckPresentIff(
         'a', 'b', 'foo', 'bar', 'baz'))
-    self.assertRaises(update_payload.PayloadError,
-                      checker.PayloadChecker._CheckPresentIff,
+    self.assertRaises(PayloadError, checker.PayloadChecker._CheckPresentIff,
                       'a', None, 'foo', 'bar', 'baz')
-    self.assertRaises(update_payload.PayloadError,
-                      checker.PayloadChecker._CheckPresentIff,
+    self.assertRaises(PayloadError, checker.PayloadChecker._CheckPresentIff,
                       None, 'b', 'foo', 'bar', 'baz')
 
   def DoCheckSha256SignatureTest(self, expect_pass, expect_subprocess_call,
@@ -298,7 +298,7 @@
         self.assertIsNone(checker.PayloadChecker._CheckSha256Signature(
             sig_data, 'foo', expected_signed_hash, 'bar'))
       else:
-        self.assertRaises(update_payload.PayloadError,
+        self.assertRaises(PayloadError,
                           checker.PayloadChecker._CheckSha256Signature,
                           sig_data, 'foo', expected_signed_hash, 'bar')
     finally:
@@ -358,31 +358,31 @@
 
   def testCheckBlocksFitLength_TooManyBlocks(self):
     """Tests _CheckBlocksFitLength(); fails due to excess blocks."""
-    self.assertRaises(update_payload.PayloadError,
+    self.assertRaises(PayloadError,
                       checker.PayloadChecker._CheckBlocksFitLength,
                       64, 5, 16, 'foo')
-    self.assertRaises(update_payload.PayloadError,
+    self.assertRaises(PayloadError,
                       checker.PayloadChecker._CheckBlocksFitLength,
                       60, 5, 16, 'foo')
-    self.assertRaises(update_payload.PayloadError,
+    self.assertRaises(PayloadError,
                       checker.PayloadChecker._CheckBlocksFitLength,
                       49, 5, 16, 'foo')
-    self.assertRaises(update_payload.PayloadError,
+    self.assertRaises(PayloadError,
                       checker.PayloadChecker._CheckBlocksFitLength,
                       48, 4, 16, 'foo')
 
   def testCheckBlocksFitLength_TooFewBlocks(self):
     """Tests _CheckBlocksFitLength(); fails due to insufficient blocks."""
-    self.assertRaises(update_payload.PayloadError,
+    self.assertRaises(PayloadError,
                       checker.PayloadChecker._CheckBlocksFitLength,
                       64, 3, 16, 'foo')
-    self.assertRaises(update_payload.PayloadError,
+    self.assertRaises(PayloadError,
                       checker.PayloadChecker._CheckBlocksFitLength,
                       60, 3, 16, 'foo')
-    self.assertRaises(update_payload.PayloadError,
+    self.assertRaises(PayloadError,
                       checker.PayloadChecker._CheckBlocksFitLength,
                       49, 3, 16, 'foo')
-    self.assertRaises(update_payload.PayloadError,
+    self.assertRaises(PayloadError,
                       checker.PayloadChecker._CheckBlocksFitLength,
                       48, 2, 16, 'foo')
 
@@ -475,8 +475,7 @@
                    fail_old_rootfs_fs_size or fail_new_kernel_fs_size or
                    fail_new_rootfs_fs_size)
     if should_fail:
-      self.assertRaises(update_payload.PayloadError,
-                        payload_checker._CheckManifest, report,
+      self.assertRaises(PayloadError, payload_checker._CheckManifest, report,
                         rootfs_part_size, kernel_part_size)
     else:
       self.assertIsNone(payload_checker._CheckManifest(report,
@@ -492,12 +491,10 @@
     self.assertIsNone(payload_checker._CheckLength(
         int(3.5 * block_size), 4, 'foo', 'bar'))
     # Fails, too few blocks.
-    self.assertRaises(update_payload.PayloadError,
-                      payload_checker._CheckLength,
+    self.assertRaises(PayloadError, payload_checker._CheckLength,
                       int(3.5 * block_size), 3, 'foo', 'bar')
     # Fails, too many blocks.
-    self.assertRaises(update_payload.PayloadError,
-                      payload_checker._CheckLength,
+    self.assertRaises(PayloadError, payload_checker._CheckLength,
                       int(3.5 * block_size), 5, 'foo', 'bar')
 
   def testCheckExtents(self):
@@ -532,30 +529,26 @@
     # Fails, extent missing a start block.
     extents = self.NewExtentList((-1, 4), (8, 3), (1024, 16))
     self.assertRaises(
-        update_payload.PayloadError, payload_checker._CheckExtents,
-        extents, (1024 + 16) * block_size, collections.defaultdict(int),
-        'foo')
+        PayloadError, payload_checker._CheckExtents, extents,
+        (1024 + 16) * block_size, collections.defaultdict(int), 'foo')
 
     # Fails, extent missing block count.
     extents = self.NewExtentList((0, -1), (8, 3), (1024, 16))
     self.assertRaises(
-        update_payload.PayloadError, payload_checker._CheckExtents,
-        extents, (1024 + 16) * block_size, collections.defaultdict(int),
-        'foo')
+        PayloadError, payload_checker._CheckExtents, extents,
+        (1024 + 16) * block_size, collections.defaultdict(int), 'foo')
 
     # Fails, extent has zero blocks.
     extents = self.NewExtentList((0, 4), (8, 3), (1024, 0))
     self.assertRaises(
-        update_payload.PayloadError, payload_checker._CheckExtents,
-        extents, (1024 + 16) * block_size, collections.defaultdict(int),
-        'foo')
+        PayloadError, payload_checker._CheckExtents, extents,
+        (1024 + 16) * block_size, collections.defaultdict(int), 'foo')
 
     # Fails, extent exceeds partition boundaries.
     extents = self.NewExtentList((0, 4), (8, 3), (1024, 16))
     self.assertRaises(
-        update_payload.PayloadError, payload_checker._CheckExtents,
-        extents, (1024 + 15) * block_size, collections.defaultdict(int),
-        'foo')
+        PayloadError, payload_checker._CheckExtents, extents,
+        (1024 + 15) * block_size, collections.defaultdict(int), 'foo')
 
   def testCheckReplaceOperation(self):
     """Tests _CheckReplaceOperation() where op.type == REPLACE."""
@@ -577,22 +570,19 @@
     # Fail, src extents founds.
     op.src_extents = ['bar']
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckReplaceOperation,
+        PayloadError, payload_checker._CheckReplaceOperation,
         op, data_length, (data_length + block_size - 1) / block_size, 'foo')
 
     # Fail, missing data.
     op.src_extents = []
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckReplaceOperation,
+        PayloadError, payload_checker._CheckReplaceOperation,
         op, None, (data_length + block_size - 1) / block_size, 'foo')
 
     # Fail, length / block number mismatch.
     op.src_extents = ['bar']
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckReplaceOperation,
+        PayloadError, payload_checker._CheckReplaceOperation,
         op, data_length, (data_length + block_size - 1) / block_size + 1, 'foo')
 
   def testCheckReplaceBzOperation(self):
@@ -615,22 +605,19 @@
     # Fail, src extents founds.
     op.src_extents = ['bar']
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckReplaceOperation,
+        PayloadError, payload_checker._CheckReplaceOperation,
         op, data_length, (data_length + block_size - 1) / block_size + 5, 'foo')
 
     # Fail, missing data.
     op.src_extents = []
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckReplaceOperation,
+        PayloadError, payload_checker._CheckReplaceOperation,
         op, None, (data_length + block_size - 1) / block_size, 'foo')
 
     # Fail, too few blocks to justify BZ.
     op.src_extents = []
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckReplaceOperation,
+        PayloadError, payload_checker._CheckReplaceOperation,
         op, data_length, (data_length + block_size - 1) / block_size, 'foo')
 
   def testCheckMoveOperation_Pass(self):
@@ -657,8 +644,7 @@
     self.AddToMessage(op.dst_extents,
                       self.NewExtentList((16, 128), (512, 6)))
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckMoveOperation,
+        PayloadError, payload_checker._CheckMoveOperation,
         op, 1024, 134, 134, 'foo')
 
   def testCheckMoveOperation_FailInsufficientSrcBlocks(self):
@@ -672,8 +658,7 @@
     self.AddToMessage(op.dst_extents,
                       self.NewExtentList((16, 128), (512, 6)))
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckMoveOperation,
+        PayloadError, payload_checker._CheckMoveOperation,
         op, None, 134, 134, 'foo')
 
   def testCheckMoveOperation_FailInsufficientDstBlocks(self):
@@ -687,8 +672,7 @@
     self.AddToMessage(op.dst_extents,
                       self.NewExtentList((16, 128), (512, 5)))
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckMoveOperation,
+        PayloadError, payload_checker._CheckMoveOperation,
         op, None, 134, 134, 'foo')
 
   def testCheckMoveOperation_FailExcessSrcBlocks(self):
@@ -702,16 +686,14 @@
     self.AddToMessage(op.dst_extents,
                       self.NewExtentList((16, 128), (512, 5)))
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckMoveOperation,
+        PayloadError, payload_checker._CheckMoveOperation,
         op, None, 134, 134, 'foo')
     self.AddToMessage(op.src_extents,
                       self.NewExtentList((1, 4), (12, 2), (1024, 129)))
     self.AddToMessage(op.dst_extents,
                       self.NewExtentList((16, 128), (512, 6)))
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckMoveOperation,
+        PayloadError, payload_checker._CheckMoveOperation,
         op, None, 134, 134, 'foo')
 
   def testCheckMoveOperation_FailExcessDstBlocks(self):
@@ -725,8 +707,7 @@
     self.AddToMessage(op.dst_extents,
                       self.NewExtentList((16, 128), (512, 7)))
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckMoveOperation,
+        PayloadError, payload_checker._CheckMoveOperation,
         op, None, 134, 134, 'foo')
 
   def testCheckMoveOperation_FailStagnantBlocks(self):
@@ -740,8 +721,7 @@
     self.AddToMessage(op.dst_extents,
                       self.NewExtentList((8, 128), (512, 6)))
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckMoveOperation,
+        PayloadError, payload_checker._CheckMoveOperation,
         op, None, 134, 134, 'foo')
 
   def testCheckMoveOperation_FailZeroStartBlock(self):
@@ -755,8 +735,7 @@
     self.AddToMessage(op.dst_extents,
                       self.NewExtentList((8, 128), (512, 6)))
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckMoveOperation,
+        PayloadError, payload_checker._CheckMoveOperation,
         op, None, 134, 134, 'foo')
 
     self.AddToMessage(op.src_extents,
@@ -764,29 +743,27 @@
     self.AddToMessage(op.dst_extents,
                       self.NewExtentList((0, 128), (512, 6)))
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckMoveOperation,
+        PayloadError, payload_checker._CheckMoveOperation,
         op, None, 134, 134, 'foo')
 
   def testCheckAnyDiff(self):
     """Tests _CheckAnyDiffOperation()."""
     payload_checker = checker.PayloadChecker(self.MockPayload())
+    op = update_metadata_pb2.InstallOperation()
 
     # Pass.
     self.assertIsNone(
-        payload_checker._CheckAnyDiffOperation(10000, 3, 'foo'))
+        payload_checker._CheckAnyDiffOperation(op, 10000, 3, 'foo'))
 
     # Fail, missing data blob.
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckAnyDiffOperation,
-        None, 3, 'foo')
+        PayloadError, payload_checker._CheckAnyDiffOperation,
+        op, None, 3, 'foo')
 
     # Fail, too big of a diff blob (unjustified).
     self.assertRaises(
-        update_payload.PayloadError,
-        payload_checker._CheckAnyDiffOperation,
-        10000, 2, 'foo')
+        PayloadError, payload_checker._CheckAnyDiffOperation,
+        op, 10000, 2, 'foo')
 
   def testCheckSourceCopyOperation_Pass(self):
     """Tests _CheckSourceCopyOperation(); pass case."""
@@ -797,15 +774,13 @@
   def testCheckSourceCopyOperation_FailContainsData(self):
     """Tests _CheckSourceCopyOperation(); message contains data."""
     payload_checker = checker.PayloadChecker(self.MockPayload())
-    self.assertRaises(update_payload.PayloadError,
-                      payload_checker._CheckSourceCopyOperation,
+    self.assertRaises(PayloadError, payload_checker._CheckSourceCopyOperation,
                       134, 0, 0, 'foo')
 
   def testCheckSourceCopyOperation_FailBlockCountsMismatch(self):
     """Tests _CheckSourceCopyOperation(); src and dst block totals not equal."""
     payload_checker = checker.PayloadChecker(self.MockPayload())
-    self.assertRaises(update_payload.PayloadError,
-                      payload_checker._CheckSourceCopyOperation,
+    self.assertRaises(PayloadError, payload_checker._CheckSourceCopyOperation,
                       None, 0, 1, 'foo')
 
   def DoCheckOperationTest(self, op_type_name, is_last, allow_signature,
@@ -818,7 +793,7 @@
 
     Args:
       op_type_name: 'REPLACE', 'REPLACE_BZ', 'MOVE', 'BSDIFF', 'SOURCE_COPY',
-        or 'SOURCE_BSDIFF'.
+        'SOURCE_BSDIFF', BROTLI_BSDIFF or 'PUFFDIFF'.
       is_last: Whether we're testing the last operation in a sequence.
       allow_signature: Whether we're testing a signature-capable operation.
       allow_unhashed: Whether we're allowing to not hash the data.
@@ -857,7 +832,8 @@
 
     total_src_blocks = 0
     if op_type in (common.OpType.MOVE, common.OpType.BSDIFF,
-                   common.OpType.SOURCE_COPY, common.OpType.SOURCE_BSDIFF):
+                   common.OpType.SOURCE_COPY, common.OpType.SOURCE_BSDIFF,
+                   common.OpType.PUFFDIFF, common.OpType.BROTLI_BSDIFF):
       if fail_src_extents:
         self.AddToMessage(op.src_extents,
                           self.NewExtentList((1, 0)))
@@ -872,6 +848,9 @@
       payload_checker.minor_version = 2 if fail_bad_minor_version else 1
     elif op_type in (common.OpType.SOURCE_COPY, common.OpType.SOURCE_BSDIFF):
       payload_checker.minor_version = 1 if fail_bad_minor_version else 2
+    elif op_type in (common.OpType.ZERO, common.OpType.DISCARD,
+                     common.OpType.PUFFDIFF, common.OpType.BROTLI_BSDIFF):
+      payload_checker.minor_version = 3 if fail_bad_minor_version else 4
 
     if op_type not in (common.OpType.MOVE, common.OpType.SOURCE_COPY):
       if not fail_mismatched_data_offset_length:
@@ -889,6 +868,7 @@
           op.data_sha256_hash = hashlib.sha256(fake_data).digest()
           payload.ReadDataBlob(op.data_offset, op.data_length).AndReturn(
               fake_data)
+
       elif fail_data_hash:
         # Create an invalid data blob hash.
         op.data_sha256_hash = hashlib.sha256(
@@ -909,7 +889,9 @@
     if total_src_blocks:
       if fail_src_length:
         op.src_length = total_src_blocks * block_size + 8
-      else:
+      elif (op_type in (common.OpType.MOVE, common.OpType.BSDIFF,
+                        common.OpType.SOURCE_BSDIFF) and
+            payload_checker.minor_version <= 3):
         op.src_length = total_src_blocks * block_size
     elif fail_src_length:
       # Add an orphaned src_length.
@@ -918,7 +900,9 @@
     if total_dst_blocks:
       if fail_dst_length:
         op.dst_length = total_dst_blocks * block_size + 8
-      else:
+      elif (op_type in (common.OpType.MOVE, common.OpType.BSDIFF,
+                        common.OpType.SOURCE_BSDIFF) and
+            payload_checker.minor_version <= 3):
         op.dst_length = total_dst_blocks * block_size
 
     self.mox.ReplayAll()
@@ -931,8 +915,7 @@
             old_part_size, new_part_size, prev_data_offset, allow_signature,
             blob_hash_counts)
     if should_fail:
-      self.assertRaises(update_payload.PayloadError,
-                        payload_checker._CheckOperation, *args)
+      self.assertRaises(PayloadError, payload_checker._CheckOperation, *args)
     else:
       self.assertEqual(op.data_length if op.HasField('data_length') else 0,
                        payload_checker._CheckOperation(*args))
@@ -954,6 +937,7 @@
     self.assertEqual(17, len(result))
 
   def DoCheckOperationsTest(self, fail_nonexhaustive_full_update):
+    """Tests _CheckOperations()."""
     # Generate a test payload. For this test, we only care about one
     # (arbitrary) set of operations, so we'll only be generating kernel and
     # test with them.
@@ -982,11 +966,10 @@
     payload_checker.payload_type = checker._TYPE_FULL
     report = checker._PayloadReport()
 
-    args = (payload_checker.payload.manifest.install_operations, report,
-            'foo', 0, rootfs_part_size, rootfs_part_size, 0, False)
+    args = (payload_checker.payload.manifest.install_operations, report, 'foo',
+            0, rootfs_part_size, rootfs_part_size, rootfs_part_size, 0, False)
     if fail_nonexhaustive_full_update:
-      self.assertRaises(update_payload.PayloadError,
-                        payload_checker._CheckOperations, *args)
+      self.assertRaises(PayloadError, payload_checker._CheckOperations, *args)
     else:
       self.assertEqual(rootfs_data_length,
                        payload_checker._CheckOperations(*args))
@@ -994,6 +977,7 @@
   def DoCheckSignaturesTest(self, fail_empty_sigs_blob, fail_missing_pseudo_op,
                             fail_mismatched_pseudo_op, fail_sig_missing_fields,
                             fail_unknown_sig_version, fail_incorrect_sig):
+    """Tests _CheckSignatures()."""
     # Generate a test payload. For this test, we only care about the signature
     # block and how it relates to the payload hash. Therefore, we're generating
     # a random (otherwise useless) payload for this purpose.
@@ -1058,8 +1042,7 @@
                    fail_unknown_sig_version or fail_incorrect_sig)
     args = (report, test_utils._PUBKEY_FILE_NAME)
     if should_fail:
-      self.assertRaises(update_payload.PayloadError,
-                        payload_checker._CheckSignatures, *args)
+      self.assertRaises(PayloadError, payload_checker._CheckSignatures, *args)
     else:
       self.assertIsNone(payload_checker._CheckSignatures(*args))
 
@@ -1088,7 +1071,7 @@
     if should_succeed:
       self.assertIsNone(payload_checker._CheckManifestMinorVersion(*args))
     else:
-      self.assertRaises(update_payload.PayloadError,
+      self.assertRaises(PayloadError,
                         payload_checker._CheckManifestMinorVersion, *args)
 
   def DoRunTest(self, rootfs_part_size_provided, kernel_part_size_provided,
@@ -1096,6 +1079,7 @@
                 fail_mismatched_block_size, fail_excess_data,
                 fail_rootfs_part_size_exceeded,
                 fail_kernel_part_size_exceeded):
+    """Tests Run()."""
     # Generate a test payload. For this test, we generate a full update that
     # has sample kernel and rootfs operations. Since most testing is done with
     # internal PayloadChecker methods that are tested elsewhere, here we only
@@ -1153,7 +1137,7 @@
             'assert_type': 'delta' if fail_wrong_payload_type else 'full',
             'block_size': use_block_size}}
     if fail_invalid_block_size:
-      self.assertRaises(update_payload.PayloadError, _GetPayloadChecker,
+      self.assertRaises(PayloadError, _GetPayloadChecker,
                         payload_gen.WriteToFileWithData, **kwargs)
     else:
       payload_checker = _GetPayloadChecker(payload_gen.WriteToFileWithData,
@@ -1167,8 +1151,7 @@
                      fail_rootfs_part_size_exceeded or
                      fail_kernel_part_size_exceeded)
       if should_fail:
-        self.assertRaises(update_payload.PayloadError, payload_checker.Run,
-                          **kwargs)
+        self.assertRaises(PayloadError, payload_checker.Run, **kwargs)
       else:
         self.assertIsNone(payload_checker.Run(**kwargs))
 
@@ -1275,7 +1258,8 @@
   AddParametricTests('CheckOperation',
                      {'op_type_name': ('REPLACE', 'REPLACE_BZ', 'MOVE',
                                        'BSDIFF', 'SOURCE_COPY',
-                                       'SOURCE_BSDIFF'),
+                                       'SOURCE_BSDIFF', 'PUFFDIFF',
+                                       'BROTLI_BSDIFF'),
                       'is_last': (True, False),
                       'allow_signature': (True, False),
                       'allow_unhashed': (True, False),
diff --git a/scripts/update_payload/common.py b/scripts/update_payload/common.py
index 678fc5d..231c504 100644
--- a/scripts/update_payload/common.py
+++ b/scripts/update_payload/common.py
@@ -6,8 +6,8 @@
 
 from __future__ import print_function
 
-from error import PayloadError
-import update_metadata_pb2
+from update_payload import update_metadata_pb2
+from update_payload.error import PayloadError
 
 
 #
@@ -27,7 +27,7 @@
 INPLACE_MINOR_PAYLOAD_VERSION = 1
 SOURCE_MINOR_PAYLOAD_VERSION = 2
 OPSRCHASH_MINOR_PAYLOAD_VERSION = 3
-IMGDIFF_MINOR_PAYLOAD_VERSION = 4
+PUFFDIFF_MINOR_PAYLOAD_VERSION = 4
 
 #
 # Payload operation types.
@@ -35,7 +35,6 @@
 class OpType(object):
   """Container for operation type constants."""
   _CLASS = update_metadata_pb2.InstallOperation
-  # pylint: disable=E1101
   REPLACE = _CLASS.REPLACE
   REPLACE_BZ = _CLASS.REPLACE_BZ
   MOVE = _CLASS.MOVE
@@ -45,9 +44,10 @@
   ZERO = _CLASS.ZERO
   DISCARD = _CLASS.DISCARD
   REPLACE_XZ = _CLASS.REPLACE_XZ
-  IMGDIFF = _CLASS.IMGDIFF
+  PUFFDIFF = _CLASS.PUFFDIFF
+  BROTLI_BSDIFF = _CLASS.BROTLI_BSDIFF
   ALL = (REPLACE, REPLACE_BZ, MOVE, BSDIFF, SOURCE_COPY, SOURCE_BSDIFF, ZERO,
-         DISCARD, REPLACE_XZ, IMGDIFF)
+         DISCARD, REPLACE_XZ, PUFFDIFF, BROTLI_BSDIFF)
   NAMES = {
       REPLACE: 'REPLACE',
       REPLACE_BZ: 'REPLACE_BZ',
@@ -58,7 +58,8 @@
       ZERO: 'ZERO',
       DISCARD: 'DISCARD',
       REPLACE_XZ: 'REPLACE_XZ',
-      IMGDIFF: 'IMGDIFF',
+      PUFFDIFF: 'PUFFDIFF',
+      BROTLI_BSDIFF: 'BROTLI_BSDIFF',
   }
 
   def __init__(self):
diff --git a/scripts/update_payload/format_utils_unittest.py b/scripts/update_payload/format_utils_unittest.py
index 8c5ba8e..7153f9e 100755
--- a/scripts/update_payload/format_utils_unittest.py
+++ b/scripts/update_payload/format_utils_unittest.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/python2
 #
 # Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
@@ -8,10 +8,11 @@
 
 import unittest
 
-import format_utils
+from update_payload import format_utils
 
 
 class NumToPercentTest(unittest.TestCase):
+  """ Tests number conversion to percentage format."""
   def testHundredPercent(self):
     self.assertEqual(format_utils.NumToPercent(1, 1), '100%')
 
@@ -43,6 +44,7 @@
 
 
 class BytesToHumanReadableTest(unittest.TestCase):
+  """ Tests number conversion to human readable format."""
   def testBaseTwo(self):
     self.assertEqual(format_utils.BytesToHumanReadable(0x1000), '4 KiB')
     self.assertEqual(format_utils.BytesToHumanReadable(0x400000), '4 MiB')
diff --git a/scripts/update_payload/histogram.py b/scripts/update_payload/histogram.py
index 9916329..f72db61 100644
--- a/scripts/update_payload/histogram.py
+++ b/scripts/update_payload/histogram.py
@@ -6,7 +6,7 @@
 
 from collections import defaultdict
 
-import format_utils
+from update_payload import format_utils
 
 
 class Histogram(object):
diff --git a/scripts/update_payload/histogram_unittest.py b/scripts/update_payload/histogram_unittest.py
index 421ff20..643bb32 100755
--- a/scripts/update_payload/histogram_unittest.py
+++ b/scripts/update_payload/histogram_unittest.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/python2
 #
 # Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
@@ -8,11 +8,12 @@
 
 import unittest
 
-import format_utils
-import histogram
+from update_payload import format_utils
+from update_payload import histogram
 
 
 class HistogramTest(unittest.TestCase):
+  """ Tests histogram"""
 
   @staticmethod
   def AddHumanReadableSize(size):
diff --git a/scripts/update_payload/payload.py b/scripts/update_payload/payload.py
index f76c0de..8d9a20e 100644
--- a/scripts/update_payload/payload.py
+++ b/scripts/update_payload/payload.py
@@ -9,12 +9,12 @@
 import hashlib
 import struct
 
-import applier
-import block_tracer
-import checker
-import common
-from error import PayloadError
-import update_metadata_pb2
+from update_payload import applier
+from update_payload import block_tracer
+from update_payload import checker
+from update_payload import common
+from update_payload import update_metadata_pb2
+from update_payload.error import PayloadError
 
 
 #
@@ -101,13 +101,15 @@
             hasher=hasher)
 
 
-  def __init__(self, payload_file):
+  def __init__(self, payload_file, payload_file_offset=0):
     """Initialize the payload object.
 
     Args:
       payload_file: update payload file object open for reading
+      payload_file_offset: the offset of the actual payload
     """
     self.payload_file = payload_file
+    self.payload_file_offset = payload_file_offset
     self.manifest_hasher = None
     self.is_init = False
     self.header = None
@@ -159,7 +161,8 @@
 
     return common.Read(
         self.payload_file, self.header.metadata_signature_len,
-        offset=self.header.size + self.header.manifest_len)
+        offset=self.payload_file_offset + self.header.size +
+        self.header.manifest_len)
 
   def ReadDataBlob(self, offset, length):
     """Reads and returns a single data blob from the update payload.
@@ -175,7 +178,8 @@
       PayloadError if a read error occurred.
     """
     return common.Read(self.payload_file, length,
-                       offset=self.data_offset + offset)
+                       offset=self.payload_file_offset + self.data_offset +
+                       offset)
 
   def Init(self):
     """Initializes the payload object.
@@ -189,11 +193,10 @@
     if self.is_init:
       raise PayloadError('payload object already initialized')
 
-    # Initialize hash context.
-    # pylint: disable=E1101
     self.manifest_hasher = hashlib.sha256()
 
     # Read the file header.
+    self.payload_file.seek(self.payload_file_offset)
     self.header = self._ReadHeader()
 
     # Read the manifest.
@@ -215,6 +218,7 @@
   def Describe(self):
     """Emits the payload embedded description data to standard output."""
     def _DescribeImageInfo(description, image_info):
+      """Display info about the image."""
       def _DisplayIndentedValue(name, value):
         print('  {:<14} {}'.format(name+':', value))
 
@@ -231,11 +235,9 @@
         _DisplayIndentedValue('Build version', image_info.build_version)
 
     if self.manifest.HasField('old_image_info'):
-      # pylint: disable=E1101
       _DescribeImageInfo('Old Image', self.manifest.old_image_info)
 
     if self.manifest.HasField('new_image_info'):
-      # pylint: disable=E1101
       _DescribeImageInfo('New Image', self.manifest.new_image_info)
 
   def _AssertInit(self):
@@ -245,7 +247,7 @@
 
   def ResetFile(self):
     """Resets the offset of the payload file to right past the manifest."""
-    self.payload_file.seek(self.data_offset)
+    self.payload_file.seek(self.payload_file_offset + self.data_offset)
 
   def IsDelta(self):
     """Returns True iff the payload appears to be a delta."""
@@ -293,7 +295,7 @@
 
   def Apply(self, new_kernel_part, new_rootfs_part, old_kernel_part=None,
             old_rootfs_part=None, bsdiff_in_place=True, bspatch_path=None,
-            truncate_to_expected_size=True):
+            puffpatch_path=None, truncate_to_expected_size=True):
     """Applies the update payload.
 
     Args:
@@ -303,6 +305,7 @@
       old_rootfs_part: name of source rootfs partition file (optional)
       bsdiff_in_place: whether to perform BSDIFF operations in-place (optional)
       bspatch_path: path to the bspatch binary (optional)
+      puffpatch_path: path to the puffpatch binary (optional)
       truncate_to_expected_size: whether to truncate the resulting partitions
                                  to their expected sizes, as specified in the
                                  payload (optional)
@@ -315,6 +318,7 @@
     # Create a short-lived payload applier object and run it.
     helper = applier.PayloadApplier(
         self, bsdiff_in_place=bsdiff_in_place, bspatch_path=bspatch_path,
+        puffpatch_path=puffpatch_path,
         truncate_to_expected_size=truncate_to_expected_size)
     helper.Run(new_kernel_part, new_rootfs_part,
                old_kernel_part=old_kernel_part,
diff --git a/scripts/update_payload/test_utils.py b/scripts/update_payload/test_utils.py
index 61a91f5..38712fb 100644
--- a/scripts/update_payload/test_utils.py
+++ b/scripts/update_payload/test_utils.py
@@ -12,9 +12,9 @@
 import struct
 import subprocess
 
-import common
-import payload
-import update_metadata_pb2
+from update_payload import common
+from update_payload import payload
+from update_payload import update_metadata_pb2
 
 
 class TestError(Exception):
@@ -84,7 +84,6 @@
   Raises:
     TestError if something goes wrong.
   """
-  # pylint: disable=E1101
   data_sha256_hash = common.SIG_ASN1_HEADER + hashlib.sha256(data).digest()
   sign_cmd = ['openssl', 'rsautl', '-sign', '-inkey', privkey_file_name]
   try:
@@ -110,8 +109,6 @@
       version: signature version (None means do not assign)
       data: signature binary data (None means do not assign)
     """
-    # Pylint fails to identify a member of the Signatures message.
-    # pylint: disable=E1101
     sig = self.sigs.signatures.add()
     if version is not None:
       sig.version = version
@@ -174,11 +171,9 @@
       part_hash: the partition hash
     """
     if is_kernel:
-      # pylint: disable=E1101
       part_info = (self.manifest.new_kernel_info if is_new
                    else self.manifest.old_kernel_info)
     else:
-      # pylint: disable=E1101
       part_info = (self.manifest.new_rootfs_info if is_new
                    else self.manifest.old_rootfs_info)
     _SetMsgField(part_info, 'size', part_size)
@@ -188,7 +183,6 @@
                    data_length=None, src_extents=None, src_length=None,
                    dst_extents=None, dst_length=None, data_sha256_hash=None):
     """Adds an InstallOperation entry."""
-    # pylint: disable=E1101
     operations = (self.manifest.kernel_install_operations if is_kernel
                   else self.manifest.install_operations)
 
@@ -293,7 +287,6 @@
     data_offset = data_length = data_sha256_hash = None
     if data_blob is not None:
       if do_hash_data_blob:
-        # pylint: disable=E1101
         data_sha256_hash = hashlib.sha256(data_blob).digest()
       data_length, data_offset = self.AddData(data_blob)
 
diff --git a/scripts/update_payload/update_metadata_pb2.py b/scripts/update_payload/update_metadata_pb2.py
index 46c475e..595f2f6 100644
--- a/scripts/update_payload/update_metadata_pb2.py
+++ b/scripts/update_payload/update_metadata_pb2.py
@@ -13,7 +13,7 @@
 DESCRIPTOR = _descriptor.FileDescriptor(
   name='update_metadata.proto',
   package='chromeos_update_engine',
-  serialized_pb='\n\x15update_metadata.proto\x12\x16\x63hromeos_update_engine\"1\n\x06\x45xtent\x12\x13\n\x0bstart_block\x18\x01 \x01(\x04\x12\x12\n\nnum_blocks\x18\x02 \x01(\x04\"z\n\nSignatures\x12@\n\nsignatures\x18\x01 \x03(\x0b\x32,.chromeos_update_engine.Signatures.Signature\x1a*\n\tSignature\x12\x0f\n\x07version\x18\x01 \x01(\r\x12\x0c\n\x04\x64\x61ta\x18\x02 \x01(\x0c\"+\n\rPartitionInfo\x12\x0c\n\x04size\x18\x01 \x01(\x04\x12\x0c\n\x04hash\x18\x02 \x01(\x0c\"w\n\tImageInfo\x12\r\n\x05\x62oard\x18\x01 \x01(\t\x12\x0b\n\x03key\x18\x02 \x01(\t\x12\x0f\n\x07\x63hannel\x18\x03 \x01(\t\x12\x0f\n\x07version\x18\x04 \x01(\t\x12\x15\n\rbuild_channel\x18\x05 \x01(\t\x12\x15\n\rbuild_version\x18\x06 \x01(\t\"\xd2\x03\n\x10InstallOperation\x12;\n\x04type\x18\x01 \x02(\x0e\x32-.chromeos_update_engine.InstallOperation.Type\x12\x13\n\x0b\x64\x61ta_offset\x18\x02 \x01(\r\x12\x13\n\x0b\x64\x61ta_length\x18\x03 \x01(\r\x12\x33\n\x0bsrc_extents\x18\x04 \x03(\x0b\x32\x1e.chromeos_update_engine.Extent\x12\x12\n\nsrc_length\x18\x05 \x01(\x04\x12\x33\n\x0b\x64st_extents\x18\x06 \x03(\x0b\x32\x1e.chromeos_update_engine.Extent\x12\x12\n\ndst_length\x18\x07 \x01(\x04\x12\x18\n\x10\x64\x61ta_sha256_hash\x18\x08 \x01(\x0c\x12\x17\n\x0fsrc_sha256_hash\x18\t \x01(\x0c\"\x91\x01\n\x04Type\x12\x0b\n\x07REPLACE\x10\x00\x12\x0e\n\nREPLACE_BZ\x10\x01\x12\x08\n\x04MOVE\x10\x02\x12\n\n\x06\x42SDIFF\x10\x03\x12\x0f\n\x0bSOURCE_COPY\x10\x04\x12\x11\n\rSOURCE_BSDIFF\x10\x05\x12\x08\n\x04ZERO\x10\x06\x12\x0b\n\x07\x44ISCARD\x10\x07\x12\x0e\n\nREPLACE_XZ\x10\x08\x12\x0b\n\x07IMGDIFF\x10\t\"\x88\x03\n\x0fPartitionUpdate\x12\x16\n\x0epartition_name\x18\x01 \x02(\t\x12\x17\n\x0frun_postinstall\x18\x02 \x01(\x08\x12\x18\n\x10postinstall_path\x18\x03 \x01(\t\x12\x17\n\x0f\x66ilesystem_type\x18\x04 \x01(\t\x12M\n\x17new_partition_signature\x18\x05 \x03(\x0b\x32,.chromeos_update_engine.Signatures.Signature\x12\x41\n\x12old_partition_info\x18\x06 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12\x41\n\x12new_partition_info\x18\x07 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12<\n\noperations\x18\x08 \x03(\x0b\x32(.chromeos_update_engine.InstallOperation\"\xc4\x05\n\x14\x44\x65ltaArchiveManifest\x12\x44\n\x12install_operations\x18\x01 \x03(\x0b\x32(.chromeos_update_engine.InstallOperation\x12K\n\x19kernel_install_operations\x18\x02 \x03(\x0b\x32(.chromeos_update_engine.InstallOperation\x12\x18\n\nblock_size\x18\x03 \x01(\r:\x04\x34\x30\x39\x36\x12\x19\n\x11signatures_offset\x18\x04 \x01(\x04\x12\x17\n\x0fsignatures_size\x18\x05 \x01(\x04\x12>\n\x0fold_kernel_info\x18\x06 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12>\n\x0fnew_kernel_info\x18\x07 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12>\n\x0fold_rootfs_info\x18\x08 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12>\n\x0fnew_rootfs_info\x18\t \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12\x39\n\x0eold_image_info\x18\n \x01(\x0b\x32!.chromeos_update_engine.ImageInfo\x12\x39\n\x0enew_image_info\x18\x0b \x01(\x0b\x32!.chromeos_update_engine.ImageInfo\x12\x18\n\rminor_version\x18\x0c \x01(\r:\x01\x30\x12;\n\npartitions\x18\r \x03(\x0b\x32\'.chromeos_update_engine.PartitionUpdateB\x02H\x03')
+  serialized_pb='\n\x15update_metadata.proto\x12\x16\x63hromeos_update_engine\"1\n\x06\x45xtent\x12\x13\n\x0bstart_block\x18\x01 \x01(\x04\x12\x12\n\nnum_blocks\x18\x02 \x01(\x04\"z\n\nSignatures\x12@\n\nsignatures\x18\x01 \x03(\x0b\x32,.chromeos_update_engine.Signatures.Signature\x1a*\n\tSignature\x12\x0f\n\x07version\x18\x01 \x01(\r\x12\x0c\n\x04\x64\x61ta\x18\x02 \x01(\x0c\"+\n\rPartitionInfo\x12\x0c\n\x04size\x18\x01 \x01(\x04\x12\x0c\n\x04hash\x18\x02 \x01(\x0c\"w\n\tImageInfo\x12\r\n\x05\x62oard\x18\x01 \x01(\t\x12\x0b\n\x03key\x18\x02 \x01(\t\x12\x0f\n\x07\x63hannel\x18\x03 \x01(\t\x12\x0f\n\x07version\x18\x04 \x01(\t\x12\x15\n\rbuild_channel\x18\x05 \x01(\t\x12\x15\n\rbuild_version\x18\x06 \x01(\t\"\xe6\x03\n\x10InstallOperation\x12;\n\x04type\x18\x01 \x02(\x0e\x32-.chromeos_update_engine.InstallOperation.Type\x12\x13\n\x0b\x64\x61ta_offset\x18\x02 \x01(\r\x12\x13\n\x0b\x64\x61ta_length\x18\x03 \x01(\r\x12\x33\n\x0bsrc_extents\x18\x04 \x03(\x0b\x32\x1e.chromeos_update_engine.Extent\x12\x12\n\nsrc_length\x18\x05 \x01(\x04\x12\x33\n\x0b\x64st_extents\x18\x06 \x03(\x0b\x32\x1e.chromeos_update_engine.Extent\x12\x12\n\ndst_length\x18\x07 \x01(\x04\x12\x18\n\x10\x64\x61ta_sha256_hash\x18\x08 \x01(\x0c\x12\x17\n\x0fsrc_sha256_hash\x18\t \x01(\x0c\"\xa5\x01\n\x04Type\x12\x0b\n\x07REPLACE\x10\x00\x12\x0e\n\nREPLACE_BZ\x10\x01\x12\x08\n\x04MOVE\x10\x02\x12\n\n\x06\x42SDIFF\x10\x03\x12\x0f\n\x0bSOURCE_COPY\x10\x04\x12\x11\n\rSOURCE_BSDIFF\x10\x05\x12\x08\n\x04ZERO\x10\x06\x12\x0b\n\x07\x44ISCARD\x10\x07\x12\x0e\n\nREPLACE_XZ\x10\x08\x12\x0c\n\x08PUFFDIFF\x10\t\x12\x11\n\rBROTLI_BSDIFF\x10\n\"\xa6\x03\n\x0fPartitionUpdate\x12\x16\n\x0epartition_name\x18\x01 \x02(\t\x12\x17\n\x0frun_postinstall\x18\x02 \x01(\x08\x12\x18\n\x10postinstall_path\x18\x03 \x01(\t\x12\x17\n\x0f\x66ilesystem_type\x18\x04 \x01(\t\x12M\n\x17new_partition_signature\x18\x05 \x03(\x0b\x32,.chromeos_update_engine.Signatures.Signature\x12\x41\n\x12old_partition_info\x18\x06 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12\x41\n\x12new_partition_info\x18\x07 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12<\n\noperations\x18\x08 \x03(\x0b\x32(.chromeos_update_engine.InstallOperation\x12\x1c\n\x14postinstall_optional\x18\t \x01(\x08\"\xc4\x05\n\x14\x44\x65ltaArchiveManifest\x12\x44\n\x12install_operations\x18\x01 \x03(\x0b\x32(.chromeos_update_engine.InstallOperation\x12K\n\x19kernel_install_operations\x18\x02 \x03(\x0b\x32(.chromeos_update_engine.InstallOperation\x12\x18\n\nblock_size\x18\x03 \x01(\r:\x04\x34\x30\x39\x36\x12\x19\n\x11signatures_offset\x18\x04 \x01(\x04\x12\x17\n\x0fsignatures_size\x18\x05 \x01(\x04\x12>\n\x0fold_kernel_info\x18\x06 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12>\n\x0fnew_kernel_info\x18\x07 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12>\n\x0fold_rootfs_info\x18\x08 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12>\n\x0fnew_rootfs_info\x18\t \x01(\x0b\x32%.chromeos_update_engine.PartitionInfo\x12\x39\n\x0eold_image_info\x18\n \x01(\x0b\x32!.chromeos_update_engine.ImageInfo\x12\x39\n\x0enew_image_info\x18\x0b \x01(\x0b\x32!.chromeos_update_engine.ImageInfo\x12\x18\n\rminor_version\x18\x0c \x01(\r:\x01\x30\x12;\n\npartitions\x18\r \x03(\x0b\x32\'.chromeos_update_engine.PartitionUpdateB\x02H\x03')
 
 
 
@@ -60,14 +60,18 @@
       options=None,
       type=None),
     _descriptor.EnumValueDescriptor(
-      name='IMGDIFF', index=9, number=9,
+      name='PUFFDIFF', index=9, number=9,
+      options=None,
+      type=None),
+    _descriptor.EnumValueDescriptor(
+      name='BROTLI_BSDIFF', index=10, number=10,
       options=None,
       type=None),
   ],
   containing_type=None,
   options=None,
   serialized_start=712,
-  serialized_end=857,
+  serialized_end=877,
 )
 
 
@@ -347,7 +351,7 @@
   is_extendable=False,
   extension_ranges=[],
   serialized_start=391,
-  serialized_end=857,
+  serialized_end=877,
 )
 
 
@@ -414,6 +418,13 @@
       message_type=None, enum_type=None, containing_type=None,
       is_extension=False, extension_scope=None,
       options=None),
+    _descriptor.FieldDescriptor(
+      name='postinstall_optional', full_name='chromeos_update_engine.PartitionUpdate.postinstall_optional', index=8,
+      number=9, type=8, cpp_type=7, label=1,
+      has_default_value=False, default_value=False,
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      options=None),
   ],
   extensions=[
   ],
@@ -423,8 +434,8 @@
   options=None,
   is_extendable=False,
   extension_ranges=[],
-  serialized_start=860,
-  serialized_end=1252,
+  serialized_start=880,
+  serialized_end=1302,
 )
 
 
@@ -535,8 +546,8 @@
   options=None,
   is_extendable=False,
   extension_ranges=[],
-  serialized_start=1255,
-  serialized_end=1963,
+  serialized_start=1305,
+  serialized_end=2013,
 )
 
 _SIGNATURES_SIGNATURE.containing_type = _SIGNATURES;
diff --git a/service_observer_interface.h b/service_observer_interface.h
index 893df04..4edb0ac 100644
--- a/service_observer_interface.h
+++ b/service_observer_interface.h
@@ -31,11 +31,8 @@
 
   // Called whenever the value of these parameters changes. For |progress|
   // value changes, this method will be called only if it changes significantly.
-  virtual void SendStatusUpdate(int64_t last_checked_time,
-                                double progress,
-                                update_engine::UpdateStatus status,
-                                const std::string& new_version,
-                                int64_t new_size) = 0;
+  virtual void SendStatusUpdate(
+      const update_engine::UpdateEngineStatus& update_engine_status) = 0;
 
   // Called whenever an update attempt is completed.
   virtual void SendPayloadApplicationComplete(ErrorCode error_code) = 0;
diff --git a/sideload_main.cc b/sideload_main.cc
index 574d062..ddb312e 100644
--- a/sideload_main.cc
+++ b/sideload_main.cc
@@ -25,7 +25,6 @@
 #include <base/strings/stringprintf.h>
 #include <brillo/asynchronous_signal_handler.h>
 #include <brillo/flag_helper.h>
-#include <brillo/make_unique_ptr.h>
 #include <brillo/message_loops/base_message_loop.h>
 #include <brillo/streams/file_stream.h>
 #include <brillo/streams/stream.h>
@@ -42,6 +41,7 @@
 using std::string;
 using std::vector;
 using update_engine::UpdateStatus;
+using update_engine::UpdateEngineStatus;
 
 namespace {
 // The root directory used for temporary files in update_engine_sideload.
@@ -81,11 +81,10 @@
   }
 
   // ServiceObserverInterface overrides.
-  void SendStatusUpdate(int64_t last_checked_time,
-                        double progress,
-                        UpdateStatus status,
-                        const string& new_version,
-                        int64_t new_size) override {
+  void SendStatusUpdate(
+      const UpdateEngineStatus& update_engine_status) override {
+    UpdateStatus status = update_engine_status.status;
+    double progress = update_engine_status.progress;
     if (status_ != status && (status == UpdateStatus::DOWNLOADING ||
                               status == UpdateStatus::FINALIZING)) {
       // Split the progress bar in two parts for the two stages DOWNLOADING and
diff --git a/system_state.h b/system_state.h
index d538427..1b0ad08 100644
--- a/system_state.h
+++ b/system_state.h
@@ -17,8 +17,6 @@
 #ifndef UPDATE_ENGINE_SYSTEM_STATE_H_
 #define UPDATE_ENGINE_SYSTEM_STATE_H_
 
-class MetricsLibraryInterface;
-
 namespace chromeos_update_manager {
 
 class UpdateManager;
@@ -40,6 +38,7 @@
 class ClockInterface;
 class ConnectionManagerInterface;
 class HardwareInterface;
+class MetricsReporterInterface;
 class OmahaRequestParams;
 class P2PManager;
 class PayloadStateInterface;
@@ -76,7 +75,7 @@
   virtual HardwareInterface* hardware() = 0;
 
   // Gets the Metrics Library interface for reporting UMA stats.
-  virtual MetricsLibraryInterface* metrics_lib() = 0;
+  virtual MetricsReporterInterface* metrics_reporter() = 0;
 
   // Gets the interface object for persisted store.
   virtual PrefsInterface* prefs() = 0;
diff --git a/test_http_server.cc b/test_http_server.cc
index 2955e79..93aa11c 100644
--- a/test_http_server.cc
+++ b/test_http_server.cc
@@ -98,9 +98,11 @@
   request->raw_headers = headers;
 
   // Break header into lines.
-  vector<string> lines;
-  base::SplitStringUsingSubstr(
-      headers.substr(0, headers.length() - strlen(EOL EOL)), EOL, &lines);
+  vector<string> lines = base::SplitStringUsingSubstr(
+      headers.substr(0, headers.length() - strlen(EOL EOL)),
+      EOL,
+      base::TRIM_WHITESPACE,
+      base::SPLIT_WANT_ALL);
 
   // Decode URL line.
   vector<string> terms = base::SplitString(lines[0], base::kWhitespaceASCII,
diff --git a/update_attempter.cc b/update_attempter.cc
index ff3b046..9cef154 100644
--- a/update_attempter.cc
+++ b/update_attempter.cc
@@ -31,10 +31,8 @@
 #include <base/rand_util.h>
 #include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
-#include <brillo/bind_lambda.h>
 #include <brillo/data_encoding.h>
 #include <brillo/errors/error_codes.h>
-#include <brillo/make_unique_ptr.h>
 #include <brillo/message_loops/message_loop.h>
 #include <policy/device_policy.h>
 #include <policy/libpolicy.h>
@@ -50,7 +48,7 @@
 #include "update_engine/common/subprocess.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/libcurl_http_fetcher.h"
-#include "update_engine/metrics.h"
+#include "update_engine/metrics_reporter_interface.h"
 #include "update_engine/omaha_request_action.h"
 #include "update_engine/omaha_request_params.h"
 #include "update_engine/omaha_response_handler_action.h"
@@ -78,6 +76,8 @@
 using std::shared_ptr;
 using std::string;
 using std::vector;
+using update_engine::UpdateAttemptFlags;
+using update_engine::UpdateEngineStatus;
 
 namespace chromeos_update_engine {
 
@@ -119,20 +119,11 @@
   return code;
 }
 
-UpdateAttempter::UpdateAttempter(
-    SystemState* system_state,
-    CertificateChecker* cert_checker,
-    org::chromium::NetworkProxyServiceInterfaceProxyInterface*
-        network_proxy_service_proxy)
+UpdateAttempter::UpdateAttempter(SystemState* system_state,
+                                 CertificateChecker* cert_checker)
     : processor_(new ActionProcessor()),
       system_state_(system_state),
-#if USE_LIBCROS
-      cert_checker_(cert_checker),
-      chrome_proxy_resolver_(network_proxy_service_proxy) {
-#else
-      cert_checker_(cert_checker) {
-#endif  // USE_LIBCROS
-}
+      cert_checker_(cert_checker) {}
 
 UpdateAttempter::~UpdateAttempter() {
   // CertificateChecker might not be initialized in unittests.
@@ -178,9 +169,8 @@
 
 void UpdateAttempter::CertificateChecked(ServerToCheck server_to_check,
                                          CertificateCheckResult result) {
-  metrics::ReportCertificateCheckMetrics(system_state_,
-                                         server_to_check,
-                                         result);
+  system_state_->metrics_reporter()->ReportCertificateCheckMetrics(
+      server_to_check, result);
 }
 
 bool UpdateAttempter::CheckAndReportDailyMetrics() {
@@ -241,7 +231,7 @@
     return;
   }
 
-  metrics::ReportDailyMetrics(system_state_, age);
+  system_state_->metrics_reporter()->ReportDailyMetrics(age);
 }
 
 void UpdateAttempter::Update(const string& app_version,
@@ -269,10 +259,11 @@
     // not performing an update check because of this.
     LOG(INFO) << "Not updating b/c we already updated and we're waiting for "
               << "reboot, we'll ping Omaha instead";
-    metrics::ReportUpdateCheckMetrics(system_state_,
-                                      metrics::CheckResult::kRebootPending,
-                                      metrics::CheckReaction::kUnset,
-                                      metrics::DownloadErrorCode::kUnset);
+    system_state_->metrics_reporter()->ReportUpdateCheckMetrics(
+        system_state_,
+        metrics::CheckResult::kRebootPending,
+        metrics::CheckReaction::kUnset,
+        metrics::DownloadErrorCode::kUnset);
     PingOmaha();
     return;
   }
@@ -328,12 +319,11 @@
   bool use_p2p_for_downloading = false;
   bool use_p2p_for_sharing = false;
 
-  // Never use p2p for downloading in interactive checks unless the
-  // developer has opted in for it via a marker file.
+  // Never use p2p for downloading in interactive checks unless the developer
+  // has opted in for it via a marker file.
   //
-  // (Why would a developer want to opt in? If he's working on the
-  // update_engine or p2p codebases so he can actually test his
-  // code.).
+  // (Why would a developer want to opt in? If they are working on the
+  // update_engine or p2p codebases so they can actually test their code.)
 
   if (system_state_ != nullptr) {
     if (!system_state_->p2p_manager()->IsP2PEnabled()) {
@@ -606,42 +596,40 @@
   shared_ptr<OmahaResponseHandlerAction> response_handler_action(
       new OmahaResponseHandlerAction(system_state_));
 
-  shared_ptr<OmahaRequestAction> download_started_action(
-      new OmahaRequestAction(system_state_,
-                             new OmahaEvent(
-                                 OmahaEvent::kTypeUpdateDownloadStarted),
-                             brillo::make_unique_ptr(new LibcurlHttpFetcher(
-                                 GetProxyResolver(),
-                                 system_state_->hardware())),
-                             false));
+  shared_ptr<OmahaRequestAction> download_started_action(new OmahaRequestAction(
+      system_state_,
+      new OmahaEvent(OmahaEvent::kTypeUpdateDownloadStarted),
+      std::make_unique<LibcurlHttpFetcher>(GetProxyResolver(),
+                                           system_state_->hardware()),
+      false));
 
   LibcurlHttpFetcher* download_fetcher =
       new LibcurlHttpFetcher(GetProxyResolver(), system_state_->hardware());
   download_fetcher->set_server_to_check(ServerToCheck::kDownload);
+  if (interactive)
+    download_fetcher->set_max_retry_count(kDownloadMaxRetryCountInteractive);
   shared_ptr<DownloadAction> download_action(
       new DownloadAction(prefs_,
                          system_state_->boot_control(),
                          system_state_->hardware(),
                          system_state_,
-                         download_fetcher));  // passes ownership
+                         download_fetcher,  // passes ownership
+                         interactive));
   shared_ptr<OmahaRequestAction> download_finished_action(
       new OmahaRequestAction(
           system_state_,
           new OmahaEvent(OmahaEvent::kTypeUpdateDownloadFinished),
-          brillo::make_unique_ptr(
-              new LibcurlHttpFetcher(GetProxyResolver(),
-                                     system_state_->hardware())),
+          std::make_unique<LibcurlHttpFetcher>(GetProxyResolver(),
+                                               system_state_->hardware()),
           false));
   shared_ptr<FilesystemVerifierAction> filesystem_verifier_action(
       new FilesystemVerifierAction());
   shared_ptr<OmahaRequestAction> update_complete_action(
-      new OmahaRequestAction(
-          system_state_,
-          new OmahaEvent(OmahaEvent::kTypeUpdateComplete),
-          brillo::make_unique_ptr(
-              new LibcurlHttpFetcher(GetProxyResolver(),
-                                     system_state_->hardware())),
-          false));
+      new OmahaRequestAction(system_state_,
+                             new OmahaEvent(OmahaEvent::kTypeUpdateComplete),
+                             std::make_unique<LibcurlHttpFetcher>(
+                                 GetProxyResolver(), system_state_->hardware()),
+                             false));
 
   download_action->set_delegate(this);
   response_handler_action_ = response_handler_action;
@@ -771,9 +759,20 @@
   return BootControlInterface::kInvalidSlot;
 }
 
-void UpdateAttempter::CheckForUpdate(const string& app_version,
+bool UpdateAttempter::CheckForUpdate(const string& app_version,
                                      const string& omaha_url,
-                                     bool interactive) {
+                                     UpdateAttemptFlags flags) {
+  bool interactive = !(flags & UpdateAttemptFlags::kFlagNonInteractive);
+
+  if (interactive && status_ != UpdateStatus::IDLE) {
+    // An update check is either in-progress, or an update has completed and the
+    // system is in UPDATED_NEED_REBOOT.  Either way, don't do an interactive
+    // update at this time
+    LOG(INFO) << "Refusing to do an interactive update with an update already "
+                 "in progress";
+    return false;
+  }
+
   LOG(INFO) << "Forced update check requested.";
   forced_app_version_.clear();
   forced_omaha_url_.clear();
@@ -795,12 +794,22 @@
     forced_omaha_url_ = constants::kOmahaDefaultAUTestURL;
   }
 
+  if (interactive) {
+    // Use the passed-in update attempt flags for this update attempt instead
+    // of the previously set ones.
+    current_update_attempt_flags_ = flags;
+    // Note: The caching for non-interactive update checks happens in
+    // OnUpdateScheduled().
+  }
+
   if (forced_update_pending_callback_.get()) {
     // Make sure that a scheduling request is made prior to calling the forced
     // update pending callback.
     ScheduleUpdates();
     forced_update_pending_callback_->Run(true, interactive);
   }
+
+  return true;
 }
 
 bool UpdateAttempter::RebootIfNeeded() {
@@ -858,6 +867,15 @@
               << (params.is_interactive ? "interactive" : "periodic")
               << " update.";
 
+    if (!params.is_interactive) {
+      // Cache the update attempt flags that will be used by this update attempt
+      // so that they can't be changed mid-way through.
+      current_update_attempt_flags_ = update_attempt_flags_;
+    }
+
+    LOG(INFO) << "Update attempt flags in use = 0x" << std::hex
+              << current_update_attempt_flags_;
+
     Update(forced_app_version_, forced_omaha_url_, params.target_channel,
            params.target_version_prefix, false, params.is_interactive);
     // Always clear the forced app_version and omaha_url after an update attempt
@@ -891,6 +909,9 @@
   // Reset cpu shares back to normal.
   cpu_limiter_.StopLimiter();
 
+  // reset the state that's only valid for a single update pass
+  current_update_attempt_flags_ = UpdateAttemptFlags::kNone;
+
   if (status_ == UpdateStatus::REPORTING_ERROR_EVENT) {
     LOG(INFO) << "Error event sent.";
 
@@ -1011,7 +1032,28 @@
       server_dictated_poll_interval_ =
           std::max(0, omaha_request_action->GetOutputObject().poll_interval);
     }
+  } else if (type == OmahaResponseHandlerAction::StaticType()) {
+    // Depending on the returned error code, note that an update is available.
+    if (code == ErrorCode::kOmahaUpdateDeferredPerPolicy ||
+        code == ErrorCode::kSuccess) {
+      // Note that the status will be updated to DOWNLOADING when some bytes
+      // get actually downloaded from the server and the BytesReceived
+      // callback is invoked. This avoids notifying the user that a download
+      // has started in cases when the server and the client are unable to
+      // initiate the download.
+      CHECK(action == response_handler_action_.get());
+      auto plan = response_handler_action_->install_plan();
+      UpdateLastCheckedTime();
+      new_version_ = plan.version;
+      new_system_version_ = plan.system_version;
+      new_payload_size_ = 0;
+      for (const auto& payload : plan.payloads)
+        new_payload_size_ += payload.size;
+      cpu_limiter_.StartLimiter();
+      SetStatusAndNotify(UpdateStatus::UPDATE_AVAILABLE);
+    }
   }
+  // General failure cases.
   if (code != ErrorCode::kSuccess) {
     // If the current state is at or past the download phase, count the failure
     // in case a switch to full update becomes necessary. Ignore network
@@ -1024,23 +1066,18 @@
     CreatePendingErrorEvent(action, code);
     return;
   }
-  // Find out which action completed.
-  if (type == OmahaResponseHandlerAction::StaticType()) {
-    // Note that the status will be updated to DOWNLOADING when some bytes get
-    // actually downloaded from the server and the BytesReceived callback is
-    // invoked. This avoids notifying the user that a download has started in
-    // cases when the server and the client are unable to initiate the download.
-    CHECK(action == response_handler_action_.get());
-    const InstallPlan& plan = response_handler_action_->install_plan();
-    UpdateLastCheckedTime();
-    new_version_ = plan.version;
-    new_payload_size_ = 0;
-    for (const auto& payload : plan.payloads)
-      new_payload_size_ += payload.size;
-    cpu_limiter_.StartLimiter();
-    SetStatusAndNotify(UpdateStatus::UPDATE_AVAILABLE);
-  } else if (type == DownloadAction::StaticType()) {
+  // Find out which action completed (successfully).
+  if (type == DownloadAction::StaticType()) {
     SetStatusAndNotify(UpdateStatus::FINALIZING);
+  } else if (type == FilesystemVerifierAction::StaticType()) {
+    // Log the system properties before the postinst and after the file system
+    // is verified. It used to be done in the postinst itself. But postinst
+    // cannot do this anymore. On the other hand, these logs are frequently
+    // looked at and it is preferable not to scatter them in random location in
+    // the log and rather log it right before the postinst. The reason not do
+    // this in the |PostinstallRunnerAction| is to prevent dependency from
+    // libpayload_consumer to libupdate_engine.
+    LogImageProperties();
   }
 }
 
@@ -1127,16 +1164,15 @@
   }
 }
 
-bool UpdateAttempter::GetStatus(int64_t* last_checked_time,
-                                double* progress,
-                                string* current_operation,
-                                string* new_version,
-                                int64_t* new_payload_size) {
-  *last_checked_time = last_checked_time_;
-  *progress = download_progress_;
-  *current_operation = UpdateStatusToString(status_);
-  *new_version = new_version_;
-  *new_payload_size = new_payload_size_;
+bool UpdateAttempter::GetStatus(UpdateEngineStatus* out_status) {
+  out_status->last_checked_time = last_checked_time_;
+  out_status->status = status_;
+  out_status->current_version = omaha_request_params_->app_version();
+  out_status->current_system_version = omaha_request_params_->system_version();
+  out_status->progress = download_progress_;
+  out_status->new_size_bytes = new_payload_size_;
+  out_status->new_version = new_version_;
+  out_status->new_system_version = new_system_version_;
   return true;
 }
 
@@ -1173,12 +1209,12 @@
 }
 
 void UpdateAttempter::BroadcastStatus() {
+  UpdateEngineStatus broadcast_status;
+  // Use common method for generating the current status.
+  GetStatus(&broadcast_status);
+
   for (const auto& observer : service_observers_) {
-    observer->SendStatusUpdate(last_checked_time_,
-                               download_progress_,
-                               status_,
-                               new_version_,
-                               new_payload_size_);
+    observer->SendStatusUpdate(broadcast_status);
   }
   last_notify_time_ = TimeTicks::Now();
 }
@@ -1283,9 +1319,8 @@
   shared_ptr<OmahaRequestAction> error_event_action(
       new OmahaRequestAction(system_state_,
                              error_event_.release(),  // Pass ownership.
-                             brillo::make_unique_ptr(new LibcurlHttpFetcher(
-                                 GetProxyResolver(),
-                                 system_state_->hardware())),
+                             std::make_unique<LibcurlHttpFetcher>(
+                                 GetProxyResolver(), system_state_->hardware()),
                              false));
   actions_.push_back(shared_ptr<AbstractAction>(error_event_action));
   processor_->EnqueueAction(error_event_action.get());
@@ -1329,9 +1364,8 @@
     shared_ptr<OmahaRequestAction> ping_action(new OmahaRequestAction(
         system_state_,
         nullptr,
-        brillo::make_unique_ptr(new LibcurlHttpFetcher(
-            GetProxyResolver(),
-            system_state_->hardware())),
+        std::make_unique<LibcurlHttpFetcher>(GetProxyResolver(),
+                                             system_state_->hardware()),
         true));
     actions_.push_back(shared_ptr<OmahaRequestAction>(ping_action));
     processor_->set_delegate(nullptr);
diff --git a/update_attempter.h b/update_attempter.h
index 7780357..76e93a2 100644
--- a/update_attempter.h
+++ b/update_attempter.h
@@ -29,9 +29,9 @@
 #include <base/time/time.h>
 #include <gtest/gtest_prod.h>  // for FRIEND_TEST
 
-#if USE_LIBCROS
+#if USE_CHROME_NETWORK_PROXY
 #include "update_engine/chrome_browser_proxy_resolver.h"
-#endif  // USE_LIBCROS
+#endif  // USE_CHROME_NETWORK_PROXY
 #include "update_engine/certificate_checker.h"
 #include "update_engine/client_library/include/update_engine/update_status.h"
 #include "update_engine/common/action_processor.h"
@@ -46,14 +46,6 @@
 #include "update_engine/update_manager/policy.h"
 #include "update_engine/update_manager/update_manager.h"
 
-class MetricsLibraryInterface;
-
-namespace org {
-namespace chromium {
-class NetworkProxyServiceInterfaceProxyInterface;
-}  // namespace chromium
-}  // namespace org
-
 namespace policy {
 class PolicyProvider;
 }
@@ -68,12 +60,10 @@
                         public PostinstallRunnerAction::DelegateInterface {
  public:
   using UpdateStatus = update_engine::UpdateStatus;
+  using UpdateAttemptFlags = update_engine::UpdateAttemptFlags;
   static const int kMaxDeltaUpdateFailures;
 
-  UpdateAttempter(SystemState* system_state,
-                  CertificateChecker* cert_checker,
-                  org::chromium::NetworkProxyServiceInterfaceProxyInterface*
-                      network_proxy_service_proxy);
+  UpdateAttempter(SystemState* system_state, CertificateChecker* cert_checker);
   ~UpdateAttempter() override;
 
   // Further initialization to be done post construction.
@@ -114,12 +104,8 @@
   // for testing purposes.
   virtual bool ResetStatus();
 
-  // Returns the current status in the out params. Returns true on success.
-  virtual bool GetStatus(int64_t* last_checked_time,
-                         double* progress,
-                         std::string* current_operation,
-                         std::string* new_version,
-                         int64_t* new_size);
+  // Returns the current status in the out param. Returns true on success.
+  virtual bool GetStatus(update_engine::UpdateEngineStatus* out_status);
 
   // Runs chromeos-setgoodkernel, whose responsibility it is to mark the
   // currently booted partition has high priority/permanent/etc. The execution
@@ -136,12 +122,28 @@
   int http_response_code() const { return http_response_code_; }
   void set_http_response_code(int code) { http_response_code_ = code; }
 
+  // Set flags that influence how updates and checks are performed.  These
+  // influence all future checks and updates until changed or the device
+  // reboots.
+  void SetUpdateAttemptFlags(UpdateAttemptFlags flags) {
+    update_attempt_flags_ = flags;
+  }
+
+  // Returns the update attempt flags that are in place for the current update
+  // attempt.  These are cached at the start of an update attempt so that they
+  // remain constant throughout the process.
+  virtual UpdateAttemptFlags GetCurrentUpdateAttemptFlags() {
+    return current_update_attempt_flags_;
+  }
+
   // This is the internal entry point for going through an
   // update. If the current status is idle invokes Update.
   // This is called by the DBus implementation.
-  virtual void CheckForUpdate(const std::string& app_version,
+  // This returns true if an update check was started, false if a check or an
+  // update was already in progress.
+  virtual bool CheckForUpdate(const std::string& app_version,
                               const std::string& omaha_url,
-                              bool is_interactive);
+                              UpdateAttemptFlags flags);
 
   // This is the internal entry point for going through a rollback. This will
   // attempt to run the postinstall on the non-active partition and set it as
@@ -252,17 +254,23 @@
   FRIEND_TEST(UpdateAttempterTest, ActionCompletedDownloadTest);
   FRIEND_TEST(UpdateAttempterTest, ActionCompletedErrorTest);
   FRIEND_TEST(UpdateAttempterTest, ActionCompletedOmahaRequestTest);
+  FRIEND_TEST(UpdateAttempterTest, BootTimeInUpdateMarkerFile);
+  FRIEND_TEST(UpdateAttempterTest, BroadcastCompleteDownloadTest);
+  FRIEND_TEST(UpdateAttempterTest, ChangeToDownloadingOnReceivedBytesTest);
   FRIEND_TEST(UpdateAttempterTest, CreatePendingErrorEventTest);
   FRIEND_TEST(UpdateAttempterTest, CreatePendingErrorEventResumedTest);
   FRIEND_TEST(UpdateAttempterTest, DisableDeltaUpdateIfNeededTest);
+  FRIEND_TEST(UpdateAttempterTest, DownloadProgressAccumulationTest);
   FRIEND_TEST(UpdateAttempterTest, MarkDeltaUpdateFailureTest);
   FRIEND_TEST(UpdateAttempterTest, PingOmahaTest);
+  FRIEND_TEST(UpdateAttempterTest, ReportDailyMetrics);
   FRIEND_TEST(UpdateAttempterTest, ScheduleErrorEventActionNoEventTest);
   FRIEND_TEST(UpdateAttempterTest, ScheduleErrorEventActionTest);
-  FRIEND_TEST(UpdateAttempterTest, UpdateTest);
-  FRIEND_TEST(UpdateAttempterTest, ReportDailyMetrics);
-  FRIEND_TEST(UpdateAttempterTest, BootTimeInUpdateMarkerFile);
   FRIEND_TEST(UpdateAttempterTest, TargetVersionPrefixSetAndReset);
+  FRIEND_TEST(UpdateAttempterTest, UpdateAttemptFlagsCachedAtUpdateStart);
+  FRIEND_TEST(UpdateAttempterTest, UpdateDeferredByPolicyTest);
+  FRIEND_TEST(UpdateAttempterTest, UpdateIsNotRunningWhenUpdateAvailable);
+  FRIEND_TEST(UpdateAttempterTest, UpdateTest);
 
   // CertificateChecker::Observer method.
   // Report metrics about the certificate being checked.
@@ -304,13 +312,13 @@
   void MarkDeltaUpdateFailure();
 
   ProxyResolver* GetProxyResolver() {
-#if USE_LIBCROS
+#if USE_CHROME_NETWORK_PROXY
     return obeying_proxies_ ?
         reinterpret_cast<ProxyResolver*>(&chrome_proxy_resolver_) :
         reinterpret_cast<ProxyResolver*>(&direct_proxy_resolver_);
 #else
     return &direct_proxy_resolver_;
-#endif  // USE_LIBCROS
+#endif  // USE_CHROME_NETWORK_PROXY
   }
 
   // Sends a ping to Omaha.
@@ -438,7 +446,13 @@
   int64_t last_checked_time_ = 0;
   std::string prev_version_;
   std::string new_version_ = "0.0.0.0";
-  int64_t new_payload_size_ = 0;
+  std::string new_system_version_;
+  uint64_t new_payload_size_ = 0;
+  // Flags influencing all periodic update checks
+  UpdateAttemptFlags update_attempt_flags_ = UpdateAttemptFlags::kNone;
+  // Flags influencing the currently in-progress check (cached at the start of
+  // the update check).
+  UpdateAttemptFlags current_update_attempt_flags_ = UpdateAttemptFlags::kNone;
 
   // Common parameters for all Omaha requests.
   OmahaRequestParams* omaha_request_params_ = nullptr;
@@ -452,9 +466,9 @@
 
   // Our two proxy resolvers
   DirectProxyResolver direct_proxy_resolver_;
-#if USE_LIBCROS
+#if USE_CHROME_NETWORK_PROXY
   ChromeBrowserProxyResolver chrome_proxy_resolver_;
-#endif  // USE_LIBCROS
+#endif  // USE_CHROME_NETWORK_PROXY
 
   // Originally, both of these flags are false. Once UpdateBootFlags is called,
   // |update_boot_flags_running_| is set to true. As soon as UpdateBootFlags
diff --git a/update_attempter_android.cc b/update_attempter_android.cc
index 6c992c8..aacb06b 100644
--- a/update_attempter_android.cc
+++ b/update_attempter_android.cc
@@ -18,8 +18,10 @@
 
 #include <algorithm>
 #include <map>
+#include <memory>
 #include <utility>
 
+#include <android-base/properties.h>
 #include <base/bind.h>
 #include <base/logging.h>
 #include <base/strings/string_number_conversions.h>
@@ -27,12 +29,14 @@
 #include <brillo/data_encoding.h>
 #include <brillo/message_loops/message_loop.h>
 #include <brillo/strings/string_utils.h>
-#include <log/log.h>
+#include <log/log_safetynet.h>
 
 #include "update_engine/common/constants.h"
 #include "update_engine/common/file_fetcher.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/daemon_state_interface.h"
+#include "update_engine/metrics_reporter_interface.h"
+#include "update_engine/metrics_utils.h"
 #include "update_engine/network_selector.h"
 #include "update_engine/payload_consumer/download_action.h"
 #include "update_engine/payload_consumer/filesystem_verifier_action.h"
@@ -46,11 +50,13 @@
 #endif
 
 using base::Bind;
+using base::Time;
 using base::TimeDelta;
 using base::TimeTicks;
 using std::shared_ptr;
 using std::string;
 using std::vector;
+using update_engine::UpdateEngineStatus;
 
 namespace chromeos_update_engine {
 
@@ -75,6 +81,13 @@
   return false;
 }
 
+bool GetHeaderAsBool(const string& header, bool default_value) {
+  int value = 0;
+  if (base::StringToInt(header, &value) && (value == 0 || value == 1))
+    return value == 1;
+  return default_value;
+}
+
 }  // namespace
 
 UpdateAttempterAndroid::UpdateAttempterAndroid(
@@ -86,7 +99,9 @@
       prefs_(prefs),
       boot_control_(boot_control),
       hardware_(hardware),
-      processor_(new ActionProcessor()) {
+      processor_(new ActionProcessor()),
+      clock_(new Clock()) {
+  metrics_reporter_ = metrics::CreateMetricsReporter();
   network_selector_ = network::CreateNetworkSelector();
 }
 
@@ -99,10 +114,12 @@
 void UpdateAttempterAndroid::Init() {
   // In case of update_engine restart without a reboot we need to restore the
   // reboot needed state.
-  if (UpdateCompletedOnThisBoot())
+  if (UpdateCompletedOnThisBoot()) {
     SetStatusAndNotify(UpdateStatus::UPDATED_NEED_REBOOT);
-  else
+  } else {
     SetStatusAndNotify(UpdateStatus::IDLE);
+    UpdatePrefsAndReportUpdateMetricsOnReboot();
+  }
 }
 
 bool UpdateAttempterAndroid::ApplyPayload(
@@ -183,10 +200,25 @@
   install_plan_.source_slot = boot_control_->GetCurrentSlot();
   install_plan_.target_slot = install_plan_.source_slot == 0 ? 1 : 0;
 
-  int data_wipe = 0;
   install_plan_.powerwash_required =
-      base::StringToInt(headers[kPayloadPropertyPowerwash], &data_wipe) &&
-      data_wipe != 0;
+      GetHeaderAsBool(headers[kPayloadPropertyPowerwash], false);
+
+  install_plan_.switch_slot_on_reboot =
+      GetHeaderAsBool(headers[kPayloadPropertySwitchSlotOnReboot], true);
+
+  install_plan_.run_post_install = true;
+  // Optionally skip post install if and only if:
+  // a) we're resuming
+  // b) post install has already succeeded before
+  // c) RUN_POST_INSTALL is set to 0.
+  if (install_plan_.is_resume && prefs_->Exists(kPrefsPostInstallSucceeded)) {
+    bool post_install_succeeded = false;
+    prefs_->GetBoolean(kPrefsPostInstallSucceeded, &post_install_succeeded);
+    if (post_install_succeeded) {
+      install_plan_.run_post_install =
+          GetHeaderAsBool(headers[kPayloadPropertyRunPostInstall], true);
+    }
+  }
 
   NetworkId network_id = kDefaultNetworkId;
   if (!headers[kPayloadPropertyNetworkId].empty()) {
@@ -222,6 +254,10 @@
   // Just in case we didn't update boot flags yet, make sure they're updated
   // before any update processing starts. This will start the update process.
   UpdateBootFlags();
+
+  UpdatePrefsOnUpdateStart(install_plan_.is_resume);
+  // TODO(xunchang) report the metrics for unresumable updates
+
   return true;
 }
 
@@ -259,6 +295,7 @@
       // after resetting to idle state, it doesn't go back to
       // UpdateStatus::UPDATED_NEED_REBOOT state.
       bool ret_value = prefs_->Delete(kPrefsUpdateCompletedOnBootId);
+      ClearMetricsPrefs();
 
       // Update the boot flags so the current slot has higher priority.
       if (!boot_control_->SetActiveBootSlot(boot_control_->GetCurrentSlot()))
@@ -299,7 +336,6 @@
       // Update succeeded.
       WriteUpdateCompletedMarker();
       prefs_->SetInt64(kPrefsDeltaUpdateFailures, 0);
-      DeltaPerformer::ResetUpdateProgress(prefs_, false);
 
       LOG(INFO) << "Update successfully applied, waiting to reboot.";
       break;
@@ -342,6 +378,11 @@
   if (type == DownloadAction::StaticType()) {
     download_progress_ = 0;
   }
+  if (type == PostinstallRunnerAction::StaticType()) {
+    bool succeeded =
+        code == ErrorCode::kSuccess || code == ErrorCode::kUpdatedButNotActive;
+    prefs_->SetBoolean(kPrefsPostInstallSucceeded, succeeded);
+  }
   if (code != ErrorCode::kSuccess) {
     // If an action failed, the ActionProcessor will cancel the whole thing.
     return;
@@ -363,6 +404,16 @@
   } else {
     ProgressUpdate(progress);
   }
+
+  // Update the bytes downloaded in prefs.
+  int64_t current_bytes_downloaded =
+      metrics_utils::GetPersistedValue(kPrefsCurrentBytesDownloaded, prefs_);
+  int64_t total_bytes_downloaded =
+      metrics_utils::GetPersistedValue(kPrefsTotalBytesDownloaded, prefs_);
+  prefs_->SetInt64(kPrefsCurrentBytesDownloaded,
+                   current_bytes_downloaded + bytes_progressed);
+  prefs_->SetInt64(kPrefsTotalBytesDownloaded,
+                   total_bytes_downloaded + bytes_progressed);
 }
 
 bool UpdateAttempterAndroid::ShouldCancel(ErrorCode* cancel_reason) {
@@ -430,17 +481,34 @@
   SetStatusAndNotify(new_status);
   ongoing_update_ = false;
 
+  // The network id is only applicable to one download attempt and once it's
+  // done the network id should not be re-used anymore.
+  if (!network_selector_->SetProcessNetwork(kDefaultNetworkId)) {
+    LOG(WARNING) << "Unable to unbind network.";
+  }
+
   for (auto observer : daemon_state_->service_observers())
     observer->SendPayloadApplicationComplete(error_code);
+
+  CollectAndReportUpdateMetricsOnUpdateFinished(error_code);
+  ClearMetricsPrefs();
+  if (error_code == ErrorCode::kSuccess) {
+    metrics_utils::SetSystemUpdatedMarker(clock_.get(), prefs_);
+    // Clear the total bytes downloaded if and only if the update succeeds.
+    prefs_->SetInt64(kPrefsTotalBytesDownloaded, 0);
+  }
 }
 
 void UpdateAttempterAndroid::SetStatusAndNotify(UpdateStatus status) {
   status_ = status;
   size_t payload_size =
       install_plan_.payloads.empty() ? 0 : install_plan_.payloads[0].size;
+  UpdateEngineStatus status_to_send = {.status = status_,
+                                       .progress = download_progress_,
+                                       .new_size_bytes = payload_size};
+
   for (auto observer : daemon_state_->service_observers()) {
-    observer->SendStatusUpdate(
-        0, download_progress_, status_, "", payload_size);
+    observer->SendStatusUpdate(status_to_send);
   }
   last_notify_time_ = TimeTicks::Now();
 }
@@ -471,8 +539,9 @@
       new DownloadAction(prefs_,
                          boot_control_,
                          hardware_,
-                         nullptr,             // system_state, not used.
-                         download_fetcher));  // passes ownership
+                         nullptr,           // system_state, not used.
+                         download_fetcher,  // passes ownership
+                         true /* is_interactive */));
   shared_ptr<FilesystemVerifierAction> filesystem_verifier_action(
       new FilesystemVerifierAction());
 
@@ -522,4 +591,153 @@
           update_completed_on_boot_id == boot_id);
 }
 
+// Collect and report the android metrics when we terminate the update.
+void UpdateAttempterAndroid::CollectAndReportUpdateMetricsOnUpdateFinished(
+    ErrorCode error_code) {
+  int64_t attempt_number =
+      metrics_utils::GetPersistedValue(kPrefsPayloadAttemptNumber, prefs_);
+  PayloadType payload_type = kPayloadTypeFull;
+  int64_t payload_size = 0;
+  for (const auto& p : install_plan_.payloads) {
+    if (p.type == InstallPayloadType::kDelta)
+      payload_type = kPayloadTypeDelta;
+    payload_size += p.size;
+  }
+
+  metrics::AttemptResult attempt_result =
+      metrics_utils::GetAttemptResult(error_code);
+  Time attempt_start_time = Time::FromInternalValue(
+      metrics_utils::GetPersistedValue(kPrefsUpdateTimestampStart, prefs_));
+  TimeDelta duration = clock_->GetBootTime() - attempt_start_time;
+  TimeDelta duration_uptime = clock_->GetMonotonicTime() - attempt_start_time;
+
+  metrics_reporter_->ReportUpdateAttemptMetrics(
+      nullptr,  // system_state
+      static_cast<int>(attempt_number),
+      payload_type,
+      duration,
+      duration_uptime,
+      payload_size,
+      attempt_result,
+      error_code);
+
+  int64_t current_bytes_downloaded =
+      metrics_utils::GetPersistedValue(kPrefsCurrentBytesDownloaded, prefs_);
+  metrics_reporter_->ReportUpdateAttemptDownloadMetrics(
+      current_bytes_downloaded,
+      0,
+      DownloadSource::kNumDownloadSources,
+      metrics::DownloadErrorCode::kUnset,
+      metrics::ConnectionType::kUnset);
+
+  if (error_code == ErrorCode::kSuccess) {
+    int64_t reboot_count =
+        metrics_utils::GetPersistedValue(kPrefsNumReboots, prefs_);
+    string build_version;
+    prefs_->GetString(kPrefsPreviousVersion, &build_version);
+
+    // For android metrics, we only care about the total bytes downloaded
+    // for all sources; for now we assume the only download source is
+    // HttpsServer.
+    int64_t total_bytes_downloaded =
+        metrics_utils::GetPersistedValue(kPrefsTotalBytesDownloaded, prefs_);
+    int64_t num_bytes_downloaded[kNumDownloadSources] = {};
+    num_bytes_downloaded[DownloadSource::kDownloadSourceHttpsServer] =
+        total_bytes_downloaded;
+
+    int download_overhead_percentage = 0;
+    if (current_bytes_downloaded > 0) {
+      download_overhead_percentage =
+          (total_bytes_downloaded - current_bytes_downloaded) * 100ull /
+          current_bytes_downloaded;
+    }
+    metrics_reporter_->ReportSuccessfulUpdateMetrics(
+        static_cast<int>(attempt_number),
+        0,  // update abandoned count
+        payload_type,
+        payload_size,
+        num_bytes_downloaded,
+        download_overhead_percentage,
+        duration,
+        static_cast<int>(reboot_count),
+        0);  // url_switch_count
+  }
+}
+
+void UpdateAttempterAndroid::UpdatePrefsAndReportUpdateMetricsOnReboot() {
+  string current_boot_id;
+  TEST_AND_RETURN(utils::GetBootId(&current_boot_id));
+  // Example: [ro.build.version.incremental]: [4292972]
+  string current_version =
+      android::base::GetProperty("ro.build.version.incremental", "");
+  TEST_AND_RETURN(!current_version.empty());
+
+  // If there's no record of previous version (e.g. due to a data wipe), we
+  // save the info of current boot and skip the metrics report.
+  if (!prefs_->Exists(kPrefsPreviousVersion)) {
+    prefs_->SetString(kPrefsBootId, current_boot_id);
+    prefs_->SetString(kPrefsPreviousVersion, current_version);
+    ClearMetricsPrefs();
+    return;
+  }
+  string previous_version;
+  // update_engine restarted under the same build.
+  // TODO(xunchang) identify and report rollback by checking UpdateMarker.
+  if (prefs_->GetString(kPrefsPreviousVersion, &previous_version) &&
+      previous_version == current_version) {
+    string last_boot_id;
+    bool is_reboot = prefs_->Exists(kPrefsBootId) &&
+                     (prefs_->GetString(kPrefsBootId, &last_boot_id) &&
+                      last_boot_id != current_boot_id);
+    // Increment the reboot number if |kPrefsNumReboots| exists. That pref is
+    // set when we start a new update.
+    if (is_reboot && prefs_->Exists(kPrefsNumReboots)) {
+      prefs_->SetString(kPrefsBootId, current_boot_id);
+      int64_t reboot_count =
+          metrics_utils::GetPersistedValue(kPrefsNumReboots, prefs_);
+      metrics_utils::SetNumReboots(reboot_count + 1, prefs_);
+    }
+    return;
+  }
+
+  // Now that the build version changes, report the update metrics.
+  // TODO(xunchang) check the build version is larger than the previous one.
+  prefs_->SetString(kPrefsBootId, current_boot_id);
+  prefs_->SetString(kPrefsPreviousVersion, current_version);
+
+  bool previous_attempt_exists = prefs_->Exists(kPrefsPayloadAttemptNumber);
+  // |kPrefsPayloadAttemptNumber| should be cleared upon successful update.
+  if (previous_attempt_exists) {
+    metrics_reporter_->ReportAbnormallyTerminatedUpdateAttemptMetrics();
+  }
+
+  metrics_utils::LoadAndReportTimeToReboot(
+      metrics_reporter_.get(), prefs_, clock_.get());
+  ClearMetricsPrefs();
+}
+
+// Save the update start time. Reset the reboot count and attempt number if the
+// update isn't a resume; otherwise increment the attempt number.
+void UpdateAttempterAndroid::UpdatePrefsOnUpdateStart(bool is_resume) {
+  if (!is_resume) {
+    metrics_utils::SetNumReboots(0, prefs_);
+    metrics_utils::SetPayloadAttemptNumber(1, prefs_);
+  } else {
+    int64_t attempt_number =
+        metrics_utils::GetPersistedValue(kPrefsPayloadAttemptNumber, prefs_);
+    metrics_utils::SetPayloadAttemptNumber(attempt_number + 1, prefs_);
+  }
+  Time update_start_time = clock_->GetMonotonicTime();
+  metrics_utils::SetUpdateTimestampStart(update_start_time, prefs_);
+}
+
+void UpdateAttempterAndroid::ClearMetricsPrefs() {
+  CHECK(prefs_);
+  prefs_->Delete(kPrefsCurrentBytesDownloaded);
+  prefs_->Delete(kPrefsNumReboots);
+  prefs_->Delete(kPrefsPayloadAttemptNumber);
+  prefs_->Delete(kPrefsSystemUpdatedMarker);
+  prefs_->Delete(kPrefsUpdateTimestampStart);
+}
+
 }  // namespace chromeos_update_engine
diff --git a/update_attempter_android.h b/update_attempter_android.h
index 167191e..28bf90a 100644
--- a/update_attempter_android.h
+++ b/update_attempter_android.h
@@ -28,9 +28,12 @@
 #include "update_engine/client_library/include/update_engine/update_status.h"
 #include "update_engine/common/action_processor.h"
 #include "update_engine/common/boot_control_interface.h"
+#include "update_engine/common/clock.h"
 #include "update_engine/common/hardware_interface.h"
 #include "update_engine/common/prefs_interface.h"
 #include "update_engine/daemon_state_interface.h"
+#include "update_engine/metrics_reporter_interface.h"
+#include "update_engine/metrics_utils.h"
 #include "update_engine/network_selector_interface.h"
 #include "update_engine/payload_consumer/download_action.h"
 #include "update_engine/payload_consumer/postinstall_runner_action.h"
@@ -86,6 +89,8 @@
   void ProgressUpdate(double progress) override;
 
  private:
+  friend class UpdateAttempterAndroidTest;
+
   // Asynchronously marks the current slot as successful if needed. If already
   // marked as good, CompleteUpdateBootFlags() is called starting the action
   // processor.
@@ -117,6 +122,41 @@
   // Returns whether an update was completed in the current boot.
   bool UpdateCompletedOnThisBoot();
 
+  // Prefs to use for metrics report
+  // |kPrefsPayloadAttemptNumber|: number of update attempts for the current
+  // payload_id.
+  // |KprefsNumReboots|: number of reboots when applying the current update.
+  // |kPrefsSystemUpdatedMarker|: end timestamp of the last successful update.
+  // |kPrefsUpdateTimestampStart|: start timestamp of the current update.
+  // |kPrefsCurrentBytesDownloaded|: number of bytes downloaded for the current
+  // payload_id.
+  // |kPrefsTotalBytesDownloaded|: number of bytes downloaded in total since
+  // the last successful update.
+
+  // Metrics report function to call:
+  //   |ReportUpdateAttemptMetrics|
+  //   |ReportSuccessfulUpdateMetrics|
+  // Prefs to update:
+  //   |kPrefsSystemUpdatedMarker|
+  void CollectAndReportUpdateMetricsOnUpdateFinished(ErrorCode error_code);
+
+  // Metrics report function to call:
+  //   |ReportAbnormallyTerminatedUpdateAttemptMetrics|
+  //   |ReportTimeToRebootMetrics|
+  // Prefs to update:
+  //   |kPrefsBootId|, |kPrefsPreviousVersion|
+  void UpdatePrefsAndReportUpdateMetricsOnReboot();
+
+  // Prefs to update:
+  //   |kPrefsPayloadAttemptNumber|, |kPrefsUpdateTimestampStart|
+  void UpdatePrefsOnUpdateStart(bool is_resume);
+
+  // Prefs to delete:
+  //   |kPrefsNumReboots|, |kPrefsPayloadAttemptNumber|,
+  //   |kPrefsSystemUpdatedMarker|, |kPrefsUpdateTimestampStart|,
+  //   |kPrefsCurrentBytesDownloaded|
+  void ClearMetricsPrefs();
+
   DaemonStateInterface* daemon_state_;
 
   // DaemonStateAndroid pointers.
@@ -162,6 +202,10 @@
   // before applying an update to the other slot.
   bool updated_boot_flags_ = false;
 
+  std::unique_ptr<ClockInterface> clock_;
+
+  std::unique_ptr<MetricsReporterInterface> metrics_reporter_;
+
   DISALLOW_COPY_AND_ASSIGN(UpdateAttempterAndroid);
 };
 
diff --git a/update_attempter_android_unittest.cc b/update_attempter_android_unittest.cc
new file mode 100644
index 0000000..94452df
--- /dev/null
+++ b/update_attempter_android_unittest.cc
@@ -0,0 +1,209 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/update_attempter_android.h"
+
+#include <memory>
+#include <string>
+
+#include <android-base/properties.h>
+#include <base/time/time.h>
+#include <gtest/gtest.h>
+
+#include "update_engine/common/fake_boot_control.h"
+#include "update_engine/common/fake_clock.h"
+#include "update_engine/common/fake_hardware.h"
+#include "update_engine/common/fake_prefs.h"
+#include "update_engine/common/mock_action_processor.h"
+#include "update_engine/common/test_utils.h"
+#include "update_engine/common/utils.h"
+#include "update_engine/daemon_state_android.h"
+#include "update_engine/mock_metrics_reporter.h"
+
+using base::Time;
+using base::TimeDelta;
+using testing::_;
+using update_engine::UpdateStatus;
+
+namespace chromeos_update_engine {
+
+class UpdateAttempterAndroidTest : public ::testing::Test {
+ protected:
+  UpdateAttempterAndroidTest() = default;
+
+  void SetUp() override {
+    clock_ = new FakeClock();
+    metrics_reporter_ = new testing::NiceMock<MockMetricsReporter>();
+    update_attempter_android_.metrics_reporter_.reset(metrics_reporter_);
+    update_attempter_android_.clock_.reset(clock_);
+    update_attempter_android_.processor_.reset(
+        new testing::NiceMock<MockActionProcessor>());
+  }
+
+  void SetUpdateStatus(update_engine::UpdateStatus status) {
+    update_attempter_android_.status_ = status;
+  }
+
+  UpdateAttempterAndroid update_attempter_android_{
+      &daemon_state_, &prefs_, &boot_control_, &hardware_};
+
+  DaemonStateAndroid daemon_state_;
+  FakePrefs prefs_;
+  FakeBootControl boot_control_;
+  FakeHardware hardware_;
+
+  FakeClock* clock_;
+  testing::NiceMock<MockMetricsReporter>* metrics_reporter_;
+};
+
+TEST_F(UpdateAttempterAndroidTest, UpdatePrefsSameBuildVersionOnInit) {
+  std::string build_version =
+      android::base::GetProperty("ro.build.version.incremental", "");
+  prefs_.SetString(kPrefsPreviousVersion, build_version);
+  prefs_.SetString(kPrefsBootId, "oldboot");
+  prefs_.SetInt64(kPrefsNumReboots, 1);
+
+  EXPECT_CALL(*metrics_reporter_, ReportTimeToReboot(_)).Times(0);
+  update_attempter_android_.Init();
+
+  // Check that the boot_id and reboot_count are updated.
+  std::string boot_id;
+  utils::GetBootId(&boot_id);
+  EXPECT_TRUE(prefs_.Exists(kPrefsBootId));
+  std::string prefs_boot_id;
+  EXPECT_TRUE(prefs_.GetString(kPrefsBootId, &prefs_boot_id));
+  EXPECT_EQ(boot_id, prefs_boot_id);
+
+  EXPECT_TRUE(prefs_.Exists(kPrefsNumReboots));
+  int64_t reboot_count;
+  EXPECT_TRUE(prefs_.GetInt64(kPrefsNumReboots, &reboot_count));
+  EXPECT_EQ(2, reboot_count);
+}
+
+TEST_F(UpdateAttempterAndroidTest, UpdatePrefsBuildVersionChangeOnInit) {
+  prefs_.SetString(kPrefsPreviousVersion, "00001");  // Set the fake version
+  prefs_.SetInt64(kPrefsPayloadAttemptNumber, 1);
+  prefs_.SetInt64(kPrefsSystemUpdatedMarker, 23456);
+
+  EXPECT_CALL(*metrics_reporter_,
+              ReportAbnormallyTerminatedUpdateAttemptMetrics())
+      .Times(1);
+
+  Time now = Time::FromInternalValue(34456);
+  clock_->SetMonotonicTime(now);
+  TimeDelta duration = now - Time::FromInternalValue(23456);
+  EXPECT_CALL(*metrics_reporter_, ReportTimeToReboot(duration.InMinutes()))
+      .Times(1);
+
+  update_attempter_android_.Init();
+  // Check that we reset the metric prefs.
+  EXPECT_FALSE(prefs_.Exists(kPrefsNumReboots));
+  EXPECT_FALSE(prefs_.Exists(kPrefsPayloadAttemptNumber));
+  EXPECT_FALSE(prefs_.Exists(kPrefsUpdateTimestampStart));
+  EXPECT_FALSE(prefs_.Exists(kPrefsSystemUpdatedMarker));
+}
+
+TEST_F(UpdateAttempterAndroidTest, ReportMetricsOnUpdateTerminated) {
+  prefs_.SetInt64(kPrefsNumReboots, 3);
+  prefs_.SetInt64(kPrefsPayloadAttemptNumber, 2);
+  prefs_.SetString(kPrefsPreviousVersion, "56789");
+  prefs_.SetInt64(kPrefsUpdateTimestampStart, 12345);
+
+  Time boot_time = Time::FromInternalValue(22345);
+  Time up_time = Time::FromInternalValue(21345);
+  clock_->SetBootTime(boot_time);
+  clock_->SetMonotonicTime(up_time);
+  TimeDelta duration = boot_time - Time::FromInternalValue(12345);
+  TimeDelta duration_uptime = up_time - Time::FromInternalValue(12345);
+  EXPECT_CALL(
+      *metrics_reporter_,
+      ReportUpdateAttemptMetrics(_,
+                                 2,
+                                 _,
+                                 duration,
+                                 duration_uptime,
+                                 _,
+                                 metrics::AttemptResult::kUpdateSucceeded,
+                                 ErrorCode::kSuccess))
+      .Times(1);
+  EXPECT_CALL(*metrics_reporter_,
+              ReportSuccessfulUpdateMetrics(2, 0, _, _, _, _, duration, 3, _))
+      .Times(1);
+
+  SetUpdateStatus(UpdateStatus::UPDATE_AVAILABLE);
+  update_attempter_android_.ProcessingDone(nullptr, ErrorCode::kSuccess);
+
+  EXPECT_FALSE(prefs_.Exists(kPrefsNumReboots));
+  EXPECT_FALSE(prefs_.Exists(kPrefsPayloadAttemptNumber));
+  EXPECT_FALSE(prefs_.Exists(kPrefsUpdateTimestampStart));
+  EXPECT_TRUE(prefs_.Exists(kPrefsSystemUpdatedMarker));
+}
+
+TEST_F(UpdateAttempterAndroidTest, ReportMetricsForBytesDownloaded) {
+  // Check both prefs are updated correctly.
+  update_attempter_android_.BytesReceived(20, 50, 200);
+  EXPECT_EQ(
+      20,
+      metrics_utils::GetPersistedValue(kPrefsCurrentBytesDownloaded, &prefs_));
+  EXPECT_EQ(
+      20,
+      metrics_utils::GetPersistedValue(kPrefsTotalBytesDownloaded, &prefs_));
+
+  EXPECT_CALL(*metrics_reporter_,
+              ReportUpdateAttemptDownloadMetrics(50, _, _, _, _))
+      .Times(1);
+  EXPECT_CALL(*metrics_reporter_,
+              ReportUpdateAttemptDownloadMetrics(40, _, _, _, _))
+      .Times(1);
+
+  int64_t total_bytes[kNumDownloadSources] = {};
+  total_bytes[kDownloadSourceHttpsServer] = 90;
+  EXPECT_CALL(*metrics_reporter_,
+              ReportSuccessfulUpdateMetrics(
+                  _,
+                  _,
+                  _,
+                  _,
+                  test_utils::DownloadSourceMatcher(total_bytes),
+                  125,
+                  _,
+                  _,
+                  _))
+      .Times(1);
+
+  // The first update fails after receving 50 bytes in total.
+  update_attempter_android_.BytesReceived(30, 50, 200);
+  update_attempter_android_.ProcessingDone(nullptr, ErrorCode::kError);
+  EXPECT_EQ(
+      0,
+      metrics_utils::GetPersistedValue(kPrefsCurrentBytesDownloaded, &prefs_));
+  EXPECT_EQ(
+      50,
+      metrics_utils::GetPersistedValue(kPrefsTotalBytesDownloaded, &prefs_));
+
+  // The second update succeeds after receiving 40 bytes, which leads to a
+  // overhead of 50 / 40 = 125%.
+  update_attempter_android_.BytesReceived(40, 40, 50);
+  update_attempter_android_.ProcessingDone(nullptr, ErrorCode::kSuccess);
+  // Both prefs should be cleared.
+  EXPECT_EQ(
+      0,
+      metrics_utils::GetPersistedValue(kPrefsCurrentBytesDownloaded, &prefs_));
+  EXPECT_EQ(
+      0, metrics_utils::GetPersistedValue(kPrefsTotalBytesDownloaded, &prefs_));
+}
+
+}  // namespace chromeos_update_engine
diff --git a/update_attempter_unittest.cc b/update_attempter_unittest.cc
index 4928477..240e4ec 100644
--- a/update_attempter_unittest.cc
+++ b/update_attempter_unittest.cc
@@ -22,8 +22,6 @@
 
 #include <base/files/file_util.h>
 #include <base/message_loop/message_loop.h>
-#include <brillo/bind_lambda.h>
-#include <brillo/make_unique_ptr.h>
 #include <brillo/message_loops/base_message_loop.h>
 #include <brillo/message_loops/message_loop.h>
 #include <brillo/message_loops/message_loop_utils.h>
@@ -31,10 +29,6 @@
 #include <policy/libpolicy.h>
 #include <policy/mock_device_policy.h>
 
-#if USE_LIBCROS
-#include "network_proxy/dbus-proxies.h"
-#include "network_proxy/dbus-proxy-mocks.h"
-#endif // USE_LIBCROS
 #include "update_engine/common/fake_clock.h"
 #include "update_engine/common/fake_prefs.h"
 #include "update_engine/common/mock_action.h"
@@ -48,24 +42,21 @@
 #include "update_engine/fake_system_state.h"
 #include "update_engine/mock_p2p_manager.h"
 #include "update_engine/mock_payload_state.h"
+#include "update_engine/mock_service_observer.h"
 #include "update_engine/payload_consumer/filesystem_verifier_action.h"
 #include "update_engine/payload_consumer/install_plan.h"
 #include "update_engine/payload_consumer/payload_constants.h"
 #include "update_engine/payload_consumer/postinstall_runner_action.h"
 
-namespace org {
-namespace chromium {
-class NetworkProxyServiceInterfaceProxyMock;
-}  // namespace chromium
-}  // namespace org
-
 using base::Time;
 using base::TimeDelta;
-using org::chromium::NetworkProxyServiceInterfaceProxyInterface;
-using org::chromium::NetworkProxyServiceInterfaceProxyMock;
+using chromeos_update_manager::EvalStatus;
+using chromeos_update_manager::UpdateCheckParams;
 using std::string;
 using std::unique_ptr;
+using testing::_;
 using testing::DoAll;
+using testing::Field;
 using testing::InSequence;
 using testing::Ne;
 using testing::NiceMock;
@@ -73,8 +64,9 @@
 using testing::Return;
 using testing::ReturnPointee;
 using testing::SaveArg;
-using testing::SetArgumentPointee;
-using testing::_;
+using testing::SetArgPointee;
+using update_engine::UpdateAttemptFlags;
+using update_engine::UpdateEngineStatus;
 using update_engine::UpdateStatus;
 
 namespace chromeos_update_engine {
@@ -84,10 +76,8 @@
 // methods.
 class UpdateAttempterUnderTest : public UpdateAttempter {
  public:
-  UpdateAttempterUnderTest(
-      SystemState* system_state,
-      NetworkProxyServiceInterfaceProxyInterface* network_proxy_service_proxy)
-      : UpdateAttempter(system_state, nullptr, network_proxy_service_proxy) {}
+  explicit UpdateAttempterUnderTest(SystemState* system_state)
+      : UpdateAttempter(system_state, nullptr) {}
 
   // Wrap the update scheduling method, allowing us to opt out of scheduled
   // updates for testing purposes.
@@ -136,7 +126,7 @@
     EXPECT_EQ(0.0, attempter_.download_progress_);
     EXPECT_EQ(0, attempter_.last_checked_time_);
     EXPECT_EQ("0.0.0.0", attempter_.new_version_);
-    EXPECT_EQ(0, attempter_.new_payload_size_);
+    EXPECT_EQ(0ULL, attempter_.new_payload_size_);
     processor_ = new NiceMock<MockActionProcessor>();
     attempter_.processor_.reset(processor_);  // Transfers ownership.
     prefs_ = fake_system_state_.mock_prefs();
@@ -187,13 +177,7 @@
   brillo::BaseMessageLoop loop_{&base_loop_};
 
   FakeSystemState fake_system_state_;
-#if USE_LIBCROS
-  NetworkProxyServiceInterfaceProxyMock network_proxy_service_proxy_mock_;
-  UpdateAttempterUnderTest attempter_{&fake_system_state_,
-                                      &network_proxy_service_proxy_mock_};
-#else
-  UpdateAttempterUnderTest attempter_{&fake_system_state_, nullptr};
-#endif  // USE_LIBCROS
+  UpdateAttempterUnderTest attempter_{&fake_system_state_};
   OpenSSLWrapper openssl_wrapper_;
   CertificateChecker certificate_checker_;
 
@@ -215,10 +199,16 @@
 TEST_F(UpdateAttempterTest, ActionCompletedDownloadTest) {
   unique_ptr<MockHttpFetcher> fetcher(new MockHttpFetcher("", 0, nullptr));
   fetcher->FailTransfer(503);  // Sets the HTTP response code.
-  DownloadAction action(prefs_, nullptr, nullptr, nullptr, fetcher.release());
+  DownloadAction action(prefs_,
+                        nullptr,
+                        nullptr,
+                        nullptr,
+                        fetcher.release(),
+                        false /* is_interactive */);
   EXPECT_CALL(*prefs_, GetInt64(kPrefsDeltaUpdateFailures, _)).Times(0);
   attempter_.ActionCompleted(nullptr, &action, ErrorCode::kSuccess);
   EXPECT_EQ(UpdateStatus::FINALIZING, attempter_.status());
+  EXPECT_EQ(0.0, attempter_.download_progress_);
   ASSERT_EQ(nullptr, attempter_.error_event_.get());
 }
 
@@ -232,6 +222,86 @@
   ASSERT_NE(nullptr, attempter_.error_event_.get());
 }
 
+TEST_F(UpdateAttempterTest, DownloadProgressAccumulationTest) {
+  // Simple test case, where all the values match (nothing was skipped)
+  uint64_t bytes_progressed_1 = 1024 * 1024;  // 1MB
+  uint64_t bytes_progressed_2 = 1024 * 1024;  // 1MB
+  uint64_t bytes_received_1 = bytes_progressed_1;
+  uint64_t bytes_received_2 = bytes_received_1 + bytes_progressed_2;
+  uint64_t bytes_total = 20 * 1024 * 1024;  // 20MB
+
+  double progress_1 =
+      static_cast<double>(bytes_received_1) / static_cast<double>(bytes_total);
+  double progress_2 =
+      static_cast<double>(bytes_received_2) / static_cast<double>(bytes_total);
+
+  EXPECT_EQ(0.0, attempter_.download_progress_);
+  // This is set via inspecting the InstallPlan payloads when the
+  // OmahaResponseAction is completed
+  attempter_.new_payload_size_ = bytes_total;
+  NiceMock<MockServiceObserver> observer;
+  EXPECT_CALL(observer,
+              SendStatusUpdate(AllOf(
+                  Field(&UpdateEngineStatus::progress, progress_1),
+                  Field(&UpdateEngineStatus::status, UpdateStatus::DOWNLOADING),
+                  Field(&UpdateEngineStatus::new_size_bytes, bytes_total))));
+  EXPECT_CALL(observer,
+              SendStatusUpdate(AllOf(
+                  Field(&UpdateEngineStatus::progress, progress_2),
+                  Field(&UpdateEngineStatus::status, UpdateStatus::DOWNLOADING),
+                  Field(&UpdateEngineStatus::new_size_bytes, bytes_total))));
+  attempter_.AddObserver(&observer);
+  attempter_.BytesReceived(bytes_progressed_1, bytes_received_1, bytes_total);
+  EXPECT_EQ(progress_1, attempter_.download_progress_);
+  // This iteration validates that a later set of updates to the variables are
+  // properly handled (so that |getStatus()| will return the same progress info
+  // as the callback is receiving.
+  attempter_.BytesReceived(bytes_progressed_2, bytes_received_2, bytes_total);
+  EXPECT_EQ(progress_2, attempter_.download_progress_);
+}
+
+TEST_F(UpdateAttempterTest, ChangeToDownloadingOnReceivedBytesTest) {
+  // The transition into UpdateStatus::DOWNLOADING happens when the
+  // first bytes are received.
+  uint64_t bytes_progressed = 1024 * 1024;    // 1MB
+  uint64_t bytes_received = 2 * 1024 * 1024;  // 2MB
+  uint64_t bytes_total = 20 * 1024 * 1024;    // 300MB
+  attempter_.status_ = UpdateStatus::CHECKING_FOR_UPDATE;
+  // This is set via inspecting the InstallPlan payloads when the
+  // OmahaResponseAction is completed
+  attempter_.new_payload_size_ = bytes_total;
+  EXPECT_EQ(0.0, attempter_.download_progress_);
+  NiceMock<MockServiceObserver> observer;
+  EXPECT_CALL(observer,
+              SendStatusUpdate(AllOf(
+                  Field(&UpdateEngineStatus::status, UpdateStatus::DOWNLOADING),
+                  Field(&UpdateEngineStatus::new_size_bytes, bytes_total))));
+  attempter_.AddObserver(&observer);
+  attempter_.BytesReceived(bytes_progressed, bytes_received, bytes_total);
+  EXPECT_EQ(UpdateStatus::DOWNLOADING, attempter_.status_);
+}
+
+TEST_F(UpdateAttempterTest, BroadcastCompleteDownloadTest) {
+  // There is a special case to ensure that at 100% downloaded,
+  // download_progress_ is updated and that value broadcast. This test confirms
+  // that.
+  uint64_t bytes_progressed = 0;              // ignored
+  uint64_t bytes_received = 5 * 1024 * 1024;  // ignored
+  uint64_t bytes_total = 5 * 1024 * 1024;     // 300MB
+  attempter_.status_ = UpdateStatus::DOWNLOADING;
+  attempter_.new_payload_size_ = bytes_total;
+  EXPECT_EQ(0.0, attempter_.download_progress_);
+  NiceMock<MockServiceObserver> observer;
+  EXPECT_CALL(observer,
+              SendStatusUpdate(AllOf(
+                  Field(&UpdateEngineStatus::progress, 1.0),
+                  Field(&UpdateEngineStatus::status, UpdateStatus::DOWNLOADING),
+                  Field(&UpdateEngineStatus::new_size_bytes, bytes_total))));
+  attempter_.AddObserver(&observer);
+  attempter_.BytesReceived(bytes_progressed, bytes_received, bytes_total);
+  EXPECT_EQ(1.0, attempter_.download_progress_);
+}
+
 TEST_F(UpdateAttempterTest, ActionCompletedOmahaRequestTest) {
   unique_ptr<MockHttpFetcher> fetcher(new MockHttpFetcher("", 0, nullptr));
   fetcher->FailTransfer(500);  // Sets the HTTP response code.
@@ -298,13 +368,13 @@
   EXPECT_TRUE(attempter_.omaha_request_params_->delta_okay());
   EXPECT_CALL(*prefs_, GetInt64(kPrefsDeltaUpdateFailures, _))
       .WillOnce(DoAll(
-          SetArgumentPointee<1>(UpdateAttempter::kMaxDeltaUpdateFailures - 1),
+          SetArgPointee<1>(UpdateAttempter::kMaxDeltaUpdateFailures - 1),
           Return(true)));
   attempter_.DisableDeltaUpdateIfNeeded();
   EXPECT_TRUE(attempter_.omaha_request_params_->delta_okay());
   EXPECT_CALL(*prefs_, GetInt64(kPrefsDeltaUpdateFailures, _))
       .WillOnce(DoAll(
-          SetArgumentPointee<1>(UpdateAttempter::kMaxDeltaUpdateFailures),
+          SetArgPointee<1>(UpdateAttempter::kMaxDeltaUpdateFailures),
           Return(true)));
   attempter_.DisableDeltaUpdateIfNeeded();
   EXPECT_FALSE(attempter_.omaha_request_params_->delta_okay());
@@ -316,10 +386,10 @@
 TEST_F(UpdateAttempterTest, MarkDeltaUpdateFailureTest) {
   EXPECT_CALL(*prefs_, GetInt64(kPrefsDeltaUpdateFailures, _))
       .WillOnce(Return(false))
-      .WillOnce(DoAll(SetArgumentPointee<1>(-1), Return(true)))
-      .WillOnce(DoAll(SetArgumentPointee<1>(1), Return(true)))
+      .WillOnce(DoAll(SetArgPointee<1>(-1), Return(true)))
+      .WillOnce(DoAll(SetArgPointee<1>(1), Return(true)))
       .WillOnce(DoAll(
-          SetArgumentPointee<1>(UpdateAttempter::kMaxDeltaUpdateFailures),
+          SetArgPointee<1>(UpdateAttempter::kMaxDeltaUpdateFailures),
           Return(true)));
   EXPECT_CALL(*prefs_, SetInt64(Ne(kPrefsDeltaUpdateFailures), _))
       .WillRepeatedly(Return(true));
@@ -386,10 +456,11 @@
 
   // Expect that the device policy is loaded by the UpdateAttempter at some
   // point by calling RefreshDevicePolicy.
-  policy::MockDevicePolicy* device_policy = new policy::MockDevicePolicy();
-  attempter_.policy_provider_.reset(new policy::PolicyProvider(device_policy));
+  auto device_policy = std::make_unique<policy::MockDevicePolicy>();
   EXPECT_CALL(*device_policy, LoadPolicy())
       .Times(testing::AtLeast(1)).WillRepeatedly(Return(true));
+  attempter_.policy_provider_.reset(
+      new policy::PolicyProvider(std::move(device_policy)));
 
   {
     InSequence s;
@@ -428,11 +499,23 @@
 void UpdateAttempterTest::RollbackTestStart(
     bool enterprise_rollback, bool valid_slot) {
   // Create a device policy so that we can change settings.
-  policy::MockDevicePolicy* device_policy = new policy::MockDevicePolicy();
-  attempter_.policy_provider_.reset(new policy::PolicyProvider(device_policy));
-
+  auto device_policy = std::make_unique<policy::MockDevicePolicy>();
   EXPECT_CALL(*device_policy, LoadPolicy()).WillRepeatedly(Return(true));
-  fake_system_state_.set_device_policy(device_policy);
+  fake_system_state_.set_device_policy(device_policy.get());
+  if (enterprise_rollback) {
+    // We return an empty owner as this is an enterprise.
+    EXPECT_CALL(*device_policy, GetOwner(_)).WillRepeatedly(
+        DoAll(SetArgPointee<0>(string("")),
+        Return(true)));
+  } else {
+    // We return a fake owner as this is an owned consumer device.
+    EXPECT_CALL(*device_policy, GetOwner(_)).WillRepeatedly(
+        DoAll(SetArgPointee<0>(string("fake.mail@fake.com")),
+        Return(true)));
+  }
+
+  attempter_.policy_provider_.reset(
+      new policy::PolicyProvider(std::move(device_policy)));
 
   if (valid_slot) {
     BootControlInterface::Slot rollback_slot = 1;
@@ -450,18 +533,6 @@
      is_rollback_allowed = true;
   }
 
-  if (enterprise_rollback) {
-    // We return an empty owner as this is an enterprise.
-    EXPECT_CALL(*device_policy, GetOwner(_)).WillRepeatedly(
-        DoAll(SetArgumentPointee<0>(string("")),
-        Return(true)));
-  } else {
-    // We return a fake owner as this is an owned consumer device.
-    EXPECT_CALL(*device_policy, GetOwner(_)).WillRepeatedly(
-        DoAll(SetArgumentPointee<0>(string("fake.mail@fake.com")),
-        Return(true)));
-  }
-
   if (is_rollback_allowed) {
     InSequence s;
     for (size_t i = 0; i < arraysize(kRollbackActionTypes); ++i) {
@@ -732,17 +803,18 @@
 void UpdateAttempterTest::ReadScatterFactorFromPolicyTestStart() {
   int64_t scatter_factor_in_seconds = 36000;
 
-  policy::MockDevicePolicy* device_policy = new policy::MockDevicePolicy();
-  attempter_.policy_provider_.reset(new policy::PolicyProvider(device_policy));
-
+  auto device_policy = std::make_unique<policy::MockDevicePolicy>();
   EXPECT_CALL(*device_policy, LoadPolicy()).WillRepeatedly(Return(true));
-  fake_system_state_.set_device_policy(device_policy);
+  fake_system_state_.set_device_policy(device_policy.get());
 
   EXPECT_CALL(*device_policy, GetScatterFactorInSeconds(_))
       .WillRepeatedly(DoAll(
-          SetArgumentPointee<0>(scatter_factor_in_seconds),
+          SetArgPointee<0>(scatter_factor_in_seconds),
           Return(true)));
 
+  attempter_.policy_provider_.reset(
+      new policy::PolicyProvider(std::move(device_policy)));
+
   attempter_.Update("", "", "", "", false, false);
   EXPECT_EQ(scatter_factor_in_seconds, attempter_.scatter_factor_.InSeconds());
 
@@ -770,17 +842,18 @@
 
   int64_t scatter_factor_in_seconds = 10;
 
-  policy::MockDevicePolicy* device_policy = new policy::MockDevicePolicy();
-  attempter_.policy_provider_.reset(new policy::PolicyProvider(device_policy));
-
+  auto device_policy = std::make_unique<policy::MockDevicePolicy>();
   EXPECT_CALL(*device_policy, LoadPolicy()).WillRepeatedly(Return(true));
-  fake_system_state_.set_device_policy(device_policy);
+  fake_system_state_.set_device_policy(device_policy.get());
 
   EXPECT_CALL(*device_policy, GetScatterFactorInSeconds(_))
       .WillRepeatedly(DoAll(
-          SetArgumentPointee<0>(scatter_factor_in_seconds),
+          SetArgPointee<0>(scatter_factor_in_seconds),
           Return(true)));
 
+  attempter_.policy_provider_.reset(
+      new policy::PolicyProvider(std::move(device_policy)));
+
   attempter_.Update("", "", "", "", false, false);
   EXPECT_EQ(scatter_factor_in_seconds, attempter_.scatter_factor_.InSeconds());
 
@@ -829,17 +902,18 @@
   // otherwise.
   int64_t scatter_factor_in_seconds = 50;
 
-  policy::MockDevicePolicy* device_policy = new policy::MockDevicePolicy();
-  attempter_.policy_provider_.reset(new policy::PolicyProvider(device_policy));
-
+  auto device_policy = std::make_unique<policy::MockDevicePolicy>();
   EXPECT_CALL(*device_policy, LoadPolicy()).WillRepeatedly(Return(true));
-  fake_system_state_.set_device_policy(device_policy);
+  fake_system_state_.set_device_policy(device_policy.get());
 
   EXPECT_CALL(*device_policy, GetScatterFactorInSeconds(_))
       .WillRepeatedly(DoAll(
-          SetArgumentPointee<0>(scatter_factor_in_seconds),
+          SetArgPointee<0>(scatter_factor_in_seconds),
           Return(true)));
 
+  attempter_.policy_provider_.reset(
+      new policy::PolicyProvider(std::move(device_policy)));
+
   // Trigger an interactive check so we can test that scattering is disabled.
   attempter_.Update("", "", "", "", false, true);
   EXPECT_EQ(scatter_factor_in_seconds, attempter_.scatter_factor_.InSeconds());
@@ -958,14 +1032,14 @@
 TEST_F(UpdateAttempterTest, CheckForUpdateAUTest) {
   fake_system_state_.fake_hardware()->SetIsOfficialBuild(true);
   fake_system_state_.fake_hardware()->SetAreDevFeaturesEnabled(false);
-  attempter_.CheckForUpdate("", "autest", true);
+  attempter_.CheckForUpdate("", "autest", UpdateAttemptFlags::kNone);
   EXPECT_EQ(constants::kOmahaDefaultAUTestURL, attempter_.forced_omaha_url());
 }
 
 TEST_F(UpdateAttempterTest, CheckForUpdateScheduledAUTest) {
   fake_system_state_.fake_hardware()->SetIsOfficialBuild(true);
   fake_system_state_.fake_hardware()->SetAreDevFeaturesEnabled(false);
-  attempter_.CheckForUpdate("", "autest-scheduled", true);
+  attempter_.CheckForUpdate("", "autest-scheduled", UpdateAttemptFlags::kNone);
   EXPECT_EQ(constants::kOmahaDefaultAUTestURL, attempter_.forced_omaha_url());
 }
 
@@ -979,4 +1053,90 @@
       fake_system_state_.request_params()->target_version_prefix().empty());
 }
 
+TEST_F(UpdateAttempterTest, UpdateDeferredByPolicyTest) {
+  // Construct an OmahaResponseHandlerAction that has processed an InstallPlan,
+  // but the update is being deferred by the Policy.
+  OmahaResponseHandlerAction* response_action =
+      new OmahaResponseHandlerAction(&fake_system_state_);
+  response_action->install_plan_.version = "a.b.c.d";
+  response_action->install_plan_.system_version = "b.c.d.e";
+  response_action->install_plan_.payloads.push_back(
+      {.size = 1234ULL, .type = InstallPayloadType::kFull});
+  attempter_.response_handler_action_.reset(response_action);
+  // Inform the UpdateAttempter that the OmahaResponseHandlerAction has
+  // completed, with the deferred-update error code.
+  attempter_.ActionCompleted(
+      nullptr, response_action, ErrorCode::kOmahaUpdateDeferredPerPolicy);
+  {
+    UpdateEngineStatus status;
+    attempter_.GetStatus(&status);
+    EXPECT_EQ(UpdateStatus::UPDATE_AVAILABLE, status.status);
+    EXPECT_EQ(response_action->install_plan_.version, status.new_version);
+    EXPECT_EQ(response_action->install_plan_.system_version,
+              status.new_system_version);
+    EXPECT_EQ(response_action->install_plan_.payloads[0].size,
+              status.new_size_bytes);
+  }
+  // An "error" event should have been created to tell Omaha that the update is
+  // being deferred.
+  EXPECT_TRUE(nullptr != attempter_.error_event_);
+  EXPECT_EQ(OmahaEvent::kTypeUpdateComplete, attempter_.error_event_->type);
+  EXPECT_EQ(OmahaEvent::kResultUpdateDeferred, attempter_.error_event_->result);
+  ErrorCode expected_code = static_cast<ErrorCode>(
+      static_cast<int>(ErrorCode::kOmahaUpdateDeferredPerPolicy) |
+      static_cast<int>(ErrorCode::kTestOmahaUrlFlag));
+  EXPECT_EQ(expected_code, attempter_.error_event_->error_code);
+  // End the processing
+  attempter_.ProcessingDone(nullptr, ErrorCode::kOmahaUpdateDeferredPerPolicy);
+  // Validate the state of the attempter.
+  {
+    UpdateEngineStatus status;
+    attempter_.GetStatus(&status);
+    EXPECT_EQ(UpdateStatus::REPORTING_ERROR_EVENT, status.status);
+    EXPECT_EQ(response_action->install_plan_.version, status.new_version);
+    EXPECT_EQ(response_action->install_plan_.system_version,
+              status.new_system_version);
+    EXPECT_EQ(response_action->install_plan_.payloads[0].size,
+              status.new_size_bytes);
+  }
+}
+
+TEST_F(UpdateAttempterTest, UpdateIsNotRunningWhenUpdateAvailable) {
+  EXPECT_FALSE(attempter_.IsUpdateRunningOrScheduled());
+  // Verify in-progress update with UPDATE_AVAILABLE is running
+  attempter_.status_ = UpdateStatus::UPDATE_AVAILABLE;
+  EXPECT_TRUE(attempter_.IsUpdateRunningOrScheduled());
+}
+
+TEST_F(UpdateAttempterTest, UpdateAttemptFlagsCachedAtUpdateStart) {
+  attempter_.SetUpdateAttemptFlags(UpdateAttemptFlags::kFlagRestrictDownload);
+
+  UpdateCheckParams params = {.updates_enabled = true};
+  attempter_.OnUpdateScheduled(EvalStatus::kSucceeded, params);
+
+  EXPECT_EQ(UpdateAttemptFlags::kFlagRestrictDownload,
+            attempter_.GetCurrentUpdateAttemptFlags());
+}
+
+TEST_F(UpdateAttempterTest, InteractiveUpdateUsesPassedRestrictions) {
+  attempter_.SetUpdateAttemptFlags(UpdateAttemptFlags::kFlagRestrictDownload);
+
+  attempter_.CheckForUpdate("", "", UpdateAttemptFlags::kNone);
+  EXPECT_EQ(UpdateAttemptFlags::kNone,
+            attempter_.GetCurrentUpdateAttemptFlags());
+}
+
+TEST_F(UpdateAttempterTest, NonInteractiveUpdateUsesSetRestrictions) {
+  attempter_.SetUpdateAttemptFlags(UpdateAttemptFlags::kNone);
+
+  // This tests that when CheckForUpdate() is called with the non-interactive
+  // flag set, that it doesn't change the current UpdateAttemptFlags.
+  attempter_.CheckForUpdate("",
+                            "",
+                            UpdateAttemptFlags::kFlagNonInteractive |
+                                UpdateAttemptFlags::kFlagRestrictDownload);
+  EXPECT_EQ(UpdateAttemptFlags::kNone,
+            attempter_.GetCurrentUpdateAttemptFlags());
+}
+
 }  // namespace chromeos_update_engine
diff --git a/update_engine.conf b/update_engine.conf
index 449e669..e3f246f 100644
--- a/update_engine.conf
+++ b/update_engine.conf
@@ -1,2 +1,2 @@
 PAYLOAD_MAJOR_VERSION=2
-PAYLOAD_MINOR_VERSION=3
+PAYLOAD_MINOR_VERSION=4
diff --git a/update_engine.gyp b/update_engine.gyp
index 6b7e5f4..f312a1d 100644
--- a/update_engine.gyp
+++ b/update_engine.gyp
@@ -14,6 +14,10 @@
 # limitations under the License.
 #
 {
+  'variables': {
+    'USE_chrome_network_proxy': '1',
+    'USE_chrome_kiosk_app': '1',
+  },
   'target_defaults': {
     'variables': {
       'deps': [
@@ -47,7 +51,8 @@
       'USE_BINDER=<(USE_binder)',
       'USE_DBUS=<(USE_dbus)',
       'USE_HWID_OVERRIDE=<(USE_hwid_override)',
-      'USE_LIBCROS=<(USE_libcros)',
+      'USE_CHROME_KIOSK_APP=<(USE_chrome_kiosk_app)',
+      'USE_CHROME_NETWORK_PROXY=<(USE_chrome_network_proxy)',
       'USE_MTD=<(USE_mtd)',
       'USE_OMAHA=1',
       'USE_SHILL=1',
@@ -80,7 +85,7 @@
         },
       },
       'sources': [
-        'update_metadata.proto'
+        'update_metadata.proto',
       ],
       'includes': ['../../../platform2/common-mk/protoc.gypi'],
     },
@@ -98,32 +103,19 @@
       'includes': ['../../../platform2/common-mk/generate-dbus-adaptors.gypi'],
     },
     {
-      'target_name': 'update_engine-other-dbus-proxies',
+      'target_name': 'update_engine-dbus-libcros-client',
       'type': 'none',
-      'actions': [
-        {
-          'action_name': 'update_engine-dbus-libcros-client',
-          'variables': {
-            'mock_output_file': 'include/libcros/dbus-proxy-mocks.h',
-            'proxy_output_file': 'include/libcros/dbus-proxies.h'
-          },
-          'sources': [
-            'dbus_bindings/org.chromium.LibCrosService.dbus-xml',
-          ],
-          'includes': ['../../../platform2/common-mk/generate-dbus-proxies.gypi'],
+      'actions': [{
+        'action_name': 'update_engine-dbus-libcros-client-action',
+        'variables': {
+          'mock_output_file': 'include/libcros/dbus-proxy-mocks.h',
+          'proxy_output_file': 'include/libcros/dbus-proxies.h',
         },
-        {
-          'action_name': 'update_engine-dbus-network_proxy-client',
-          'variables': {
-            'mock_output_file': 'include/network_proxy/dbus-proxy-mocks.h',
-            'proxy_output_file': 'include/network_proxy/dbus-proxies.h'
-          },
-          'sources': [
-            'dbus_bindings/org.chromium.NetworkProxyService.dbus-xml',
-          ],
-          'includes': ['../../../platform2/common-mk/generate-dbus-proxies.gypi'],
-        },
-      ],
+        'sources': [
+          'dbus_bindings/org.chromium.LibCrosService.dbus-xml',
+        ],
+        'includes': ['../../../platform2/common-mk/generate-dbus-proxies.gypi'],
+      }],
     },
     # The payload application component and common dependencies.
     {
@@ -138,6 +130,7 @@
         'exported_deps': [
           'libcrypto',
           'xz-embedded',
+          'libpuffpatch',
         ],
         'deps': ['<@(exported_deps)'],
       },
@@ -178,10 +171,13 @@
         'common/terminator.cc',
         'common/utils.cc',
         'payload_consumer/bzip_extent_writer.cc',
+        'payload_consumer/cached_file_descriptor.cc',
         'payload_consumer/delta_performer.cc',
         'payload_consumer/download_action.cc',
+        'payload_consumer/extent_reader.cc',
         'payload_consumer/extent_writer.cc',
         'payload_consumer/file_descriptor.cc',
+        'payload_consumer/file_descriptor_utils.cc',
         'payload_consumer/file_writer.cc',
         'payload_consumer/filesystem_verifier_action.cc',
         'payload_consumer/install_plan.cc',
@@ -212,7 +208,6 @@
         'libpayload_consumer',
         'update_metadata-protos',
         'update_engine-dbus-adaptor',
-        'update_engine-other-dbus-proxies',
       ],
       'variables': {
         'exported_deps': [
@@ -226,6 +221,7 @@
           'libshill-client',
           'libssl',
           'libupdate_engine-client',
+          'vboot_host',
         ],
         'deps': ['<@(exported_deps)'],
       },
@@ -247,7 +243,6 @@
           '-lpolicy-<(libbase_ver)',
           '-lrootdev',
           '-lrt',
-          '-lvboot_host',
         ],
       },
       'sources': [
@@ -262,7 +257,7 @@
         'hardware_chromeos.cc',
         'image_properties_chromeos.cc',
         'libcurl_http_fetcher.cc',
-        'metrics.cc',
+        'metrics_reporter_omaha.cc',
         'metrics_utils.cc',
         'omaha_request_action.cc',
         'omaha_request_params.cc',
@@ -292,14 +287,16 @@
         'update_status_utils.cc',
       ],
       'conditions': [
-        ['USE_libcros == 1', {
-          'dependencies': [
-            'update_engine-other-dbus-proxies',
-          ],
+        ['USE_chrome_network_proxy == 1', {
           'sources': [
             'chrome_browser_proxy_resolver.cc',
           ],
         }],
+        ['USE_chrome_kiosk_app == 1', {
+          'dependencies': [
+            'update_engine-dbus-libcros-client',
+          ],
+        }],
       ],
     },
     # update_engine daemon.
@@ -343,7 +340,7 @@
         'common/error_code_utils.cc',
         'omaha_utils.cc',
         'update_engine_client.cc',
-     ],
+      ],
     },
     # server-side code. This is used for delta_generator and unittests but not
     # for any client code.
@@ -357,6 +354,7 @@
       'variables': {
         'exported_deps': [
           'ext2fs',
+          'libpuffdiff',
         ],
         'deps': ['<@(exported_deps)'],
       },
@@ -373,6 +371,9 @@
             '<@(exported_deps)',
           ],
         },
+        'libraries': [
+          '-lbsdiff',
+        ],
       },
       'sources': [
         'payload_generator/ab_generator.cc',
@@ -381,6 +382,7 @@
         'payload_generator/block_mapping.cc',
         'payload_generator/bzip.cc',
         'payload_generator/cycle_breaker.cc',
+        'payload_generator/deflate_utils.cc',
         'payload_generator/delta_diff_generator.cc',
         'payload_generator/delta_diff_utils.cc',
         'payload_generator/ext2_filesystem.cc',
@@ -395,6 +397,7 @@
         'payload_generator/payload_generation_config.cc',
         'payload_generator/payload_signer.cc',
         'payload_generator/raw_filesystem.cc',
+        'payload_generator/squashfs_filesystem.cc',
         'payload_generator/tarjan.cc',
         'payload_generator/topological_sort.cc',
         'payload_generator/xz_chromeos.cc',
@@ -468,7 +471,6 @@
         {
           'target_name': 'update_engine_unittests',
           'type': 'executable',
-          'includes': ['../../../platform2/common-mk/common_test.gypi'],
           'variables': {
             'deps': [
               'libbrillo-test-<(libbase_ver)',
@@ -508,6 +510,7 @@
             'fake_system_state.cc',
             'hardware_chromeos_unittest.cc',
             'image_properties_chromeos_unittest.cc',
+            'metrics_reporter_omaha_unittest.cc',
             'metrics_utils_unittest.cc',
             'omaha_request_action_unittest.cc',
             'omaha_request_params_unittest.cc',
@@ -515,10 +518,14 @@
             'omaha_utils_unittest.cc',
             'p2p_manager_unittest.cc',
             'payload_consumer/bzip_extent_writer_unittest.cc',
+            'payload_consumer/cached_file_descriptor_unittest.cc',
             'payload_consumer/delta_performer_integration_test.cc',
             'payload_consumer/delta_performer_unittest.cc',
             'payload_consumer/download_action_unittest.cc',
+            'payload_consumer/extent_reader_unittest.cc',
             'payload_consumer/extent_writer_unittest.cc',
+            'payload_consumer/fake_file_descriptor.cc',
+            'payload_consumer/file_descriptor_utils_unittest.cc',
             'payload_consumer/file_writer_unittest.cc',
             'payload_consumer/filesystem_verifier_action_unittest.cc',
             'payload_consumer/postinstall_runner_action_unittest.cc',
@@ -527,6 +534,7 @@
             'payload_generator/blob_file_writer_unittest.cc',
             'payload_generator/block_mapping_unittest.cc',
             'payload_generator/cycle_breaker_unittest.cc',
+            'payload_generator/deflate_utils_unittest.cc',
             'payload_generator/delta_diff_utils_unittest.cc',
             'payload_generator/ext2_filesystem_unittest.cc',
             'payload_generator/extent_ranges_unittest.cc',
@@ -539,11 +547,13 @@
             'payload_generator/payload_file_unittest.cc',
             'payload_generator/payload_generation_config_unittest.cc',
             'payload_generator/payload_signer_unittest.cc',
+            'payload_generator/squashfs_filesystem_unittest.cc',
             'payload_generator/tarjan_unittest.cc',
             'payload_generator/topological_sort_unittest.cc',
             'payload_generator/zip_unittest.cc',
             'payload_state_unittest.cc',
             'proxy_resolver_unittest.cc',
+            'testrunner.cc',
             'update_attempter_unittest.cc',
             'update_manager/boxed_value_unittest.cc',
             'update_manager/chromeos_policy_unittest.cc',
@@ -559,15 +569,6 @@
             'update_manager/umtest_utils.cc',
             'update_manager/update_manager_unittest.cc',
             'update_manager/variable_unittest.cc',
-            # Main entry point for runnning tests.
-            'testrunner.cc',
-          ],
-          'conditions': [
-            ['USE_libcros == 1', {
-              'sources': [
-                'chrome_browser_proxy_resolver_unittest.cc',
-              ],
-            }],
           ],
         },
       ],
diff --git a/update_engine.rc b/update_engine.rc
index b6a706a..a7d6235 100644
--- a/update_engine.rc
+++ b/update_engine.rc
@@ -1,5 +1,9 @@
-service update_engine /system/bin/update_engine --logtostderr --foreground
+service update_engine /system/bin/update_engine --logtostderr --logtofile --foreground
     class late_start
     user root
     group root system wakelock inet cache
     writepid /dev/cpuset/system-background/tasks
+    disabled
+
+on property:ro.boot.slot_suffix=*
+    enable update_engine
diff --git a/update_engine_client.cc b/update_engine_client.cc
index 44897e0..bb19632 100644
--- a/update_engine_client.cc
+++ b/update_engine_client.cc
@@ -26,6 +26,7 @@
 #include <base/command_line.h>
 #include <base/logging.h>
 #include <base/macros.h>
+#include <base/threading/platform_thread.h>
 #include <brillo/daemons/daemon.h>
 #include <brillo/flag_helper.h>
 
@@ -52,6 +53,11 @@
 // initialization.
 const int kContinueRunning = -1;
 
+// The ShowStatus request will be retried `kShowStatusRetryCount` times at
+// `kShowStatusRetryInterval` second intervals on failure.
+const int kShowStatusRetryCount = 30;
+const int kShowStatusRetryIntervalInSeconds = 2;
+
 class UpdateEngineClient : public brillo::Daemon {
  public:
   UpdateEngineClient(int argc, char** argv) : argc_(argc), argv_(argv) {
@@ -73,7 +79,7 @@
 
     // We can't call QuitWithExitCode from OnInit(), so we delay the execution
     // of the ProcessFlags method after the Daemon initialization is done.
-    base::MessageLoop::current()->PostTask(
+    base::MessageLoop::current()->task_runner()->PostTask(
         FROM_HERE,
         base::Bind(&UpdateEngineClient::ProcessFlagsAndExit,
                    base::Unretained(this)));
@@ -151,9 +157,18 @@
   string new_version;
   int64_t new_size = 0;
 
-  if (!client_->GetStatus(&last_checked_time, &progress, &current_op,
-                          &new_version, &new_size)) {
-    return false;
+  int retry_count = kShowStatusRetryCount;
+  while (retry_count > 0) {
+    if (client_->GetStatus(&last_checked_time, &progress, &current_op,
+                           &new_version, &new_size)) {
+      break;
+    }
+    if (--retry_count == 0) {
+      return false;
+    }
+    LOG(WARNING) << "Will try " << retry_count << " more times!";
+    base::PlatformThread::Sleep(
+        base::TimeDelta::FromSeconds(kShowStatusRetryIntervalInSeconds));
   }
 
   printf("LAST_CHECKED_TIME=%" PRIi64
diff --git a/update_engine_client_android.cc b/update_engine_client_android.cc
index 989a97e..267f6e9 100644
--- a/update_engine_client_android.cc
+++ b/update_engine_client_android.cc
@@ -97,7 +97,10 @@
   ErrorCode code = static_cast<ErrorCode>(error_code);
   LOG(INFO) << "onPayloadApplicationComplete(" << utils::ErrorCodeToString(code)
             << " (" << error_code << "))";
-  client_->ExitWhenIdle(code == ErrorCode::kSuccess ? EX_OK : 1);
+  client_->ExitWhenIdle(
+      (code == ErrorCode::kSuccess || code == ErrorCode::kUpdatedButNotActive)
+          ? EX_OK
+          : 1);
   return Status::ok();
 }
 
diff --git a/update_manager/android_things_policy.cc b/update_manager/android_things_policy.cc
new file mode 100644
index 0000000..5fbda46
--- /dev/null
+++ b/update_manager/android_things_policy.cc
@@ -0,0 +1,180 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/update_manager/android_things_policy.h"
+
+#include <string>
+#include <vector>
+
+#include <base/logging.h>
+#include <base/time/time.h>
+
+#include "update_engine/update_manager/api_restricted_downloads_policy_impl.h"
+#include "update_engine/update_manager/enough_slots_ab_updates_policy_impl.h"
+#include "update_engine/update_manager/interactive_update_policy_impl.h"
+#include "update_engine/update_manager/official_build_check_policy_impl.h"
+
+using base::Time;
+using chromeos_update_engine::ErrorCode;
+using std::string;
+using std::vector;
+
+namespace chromeos_update_manager {
+
+const NextUpdateCheckPolicyConstants
+    AndroidThingsPolicy::kNextUpdateCheckPolicyConstants = {
+        .timeout_initial_interval = 7 * 60,
+        .timeout_periodic_interval = 5 * 60 * 60,
+        .timeout_max_backoff_interval = 26 * 60 * 60,
+        .timeout_regular_fuzz = 10 * 60,
+        .attempt_backoff_max_interval_in_days = 16,
+        .attempt_backoff_fuzz_in_hours = 12,
+};
+
+EvalStatus AndroidThingsPolicy::UpdateCheckAllowed(
+    EvaluationContext* ec,
+    State* state,
+    string* error,
+    UpdateCheckParams* result) const {
+  // Set the default return values.
+  result->updates_enabled = true;
+  result->target_channel.clear();
+  result->target_version_prefix.clear();
+  result->is_interactive = false;
+
+  // Build a list of policies to consult.  Note that each policy may modify the
+  // result structure, even if it signals kContinue.
+  EnoughSlotsAbUpdatesPolicyImpl enough_slots_ab_updates_policy;
+  OnlyUpdateOfficialBuildsPolicyImpl only_update_official_builds_policy;
+  InteractiveUpdatePolicyImpl interactive_update_policy;
+  NextUpdateCheckTimePolicyImpl next_update_check_time_policy(
+      kNextUpdateCheckPolicyConstants);
+
+  vector<Policy const*> policies_to_consult = {
+      // Do not perform any updates if there are not enough slots to do
+      // A/B updates
+      &enough_slots_ab_updates_policy,
+
+      // Unofficial builds should not perform periodic update checks.
+      &only_update_official_builds_policy,
+
+      // Check to see if an interactive update was requested.
+      &interactive_update_policy,
+
+      // Ensure that periodic update checks are timed properly.
+      &next_update_check_time_policy,
+  };
+
+  // Now that the list of policy implementations, and the order to consult them,
+  // as been setup, do that.  If none of the policies make a definitive
+  // decisions about whether or not to check for updates, then allow the update
+  // check to happen.
+  EvalStatus status = ConsultPolicies(policies_to_consult,
+                                      &Policy::UpdateCheckAllowed,
+                                      ec,
+                                      state,
+                                      error,
+                                      result);
+  if (status != EvalStatus::kContinue) {
+    return status;
+  } else {
+    // It is time to check for an update.
+    LOG(INFO) << "Allowing update check.";
+    return EvalStatus::kSucceeded;
+  }
+}
+
+// Uses the |UpdateRestrictions| to determine if the download and apply can
+// occur at this time.
+EvalStatus AndroidThingsPolicy::UpdateCanBeApplied(
+    EvaluationContext* ec,
+    State* state,
+    string* error,
+    ErrorCode* result,
+    chromeos_update_engine::InstallPlan* install_plan) const {
+  // Build a list of policies to consult.  Note that each policy may modify the
+  // result structure, even if it signals kContinue.
+  ApiRestrictedDownloadsPolicyImpl api_restricted_downloads_policy;
+
+  vector<Policy const*> policies_to_consult = {
+      // Do not apply the update if all updates are restricted by the API.
+      &api_restricted_downloads_policy,
+  };
+
+  // Now that the list of policy implementations, and the order to consult them,
+  // as been setup, do that.  If none of the policies make a definitive
+  // decisions about whether or not to check for updates, then allow the update
+  // check to happen.
+  EvalStatus status = ConsultPolicies(policies_to_consult,
+                                      &Policy::UpdateCanBeApplied,
+                                      ec,
+                                      state,
+                                      error,
+                                      result,
+                                      install_plan);
+  if (EvalStatus::kContinue != status) {
+    return status;
+  } else {
+    // The update can proceed.
+    LOG(INFO) << "Allowing update to be applied.";
+    *result = ErrorCode::kSuccess;
+    return EvalStatus::kSucceeded;
+  }
+}
+
+// Always returns |EvalStatus::kSucceeded|
+EvalStatus AndroidThingsPolicy::UpdateCanStart(EvaluationContext* ec,
+                                               State* state,
+                                               string* error,
+                                               UpdateDownloadParams* result,
+                                               UpdateState update_state) const {
+  // Update is good to go.
+  result->update_can_start = true;
+  return EvalStatus::kSucceeded;
+}
+
+// Always returns |EvalStatus::kSucceeded|
+EvalStatus AndroidThingsPolicy::UpdateDownloadAllowed(EvaluationContext* ec,
+                                                      State* state,
+                                                      string* error,
+                                                      bool* result) const {
+  // By default, we allow updates.
+  *result = true;
+  return EvalStatus::kSucceeded;
+}
+
+// P2P is always disabled.  Returns |result|==|false| and
+// |EvalStatus::kSucceeded|
+EvalStatus AndroidThingsPolicy::P2PEnabled(EvaluationContext* ec,
+                                           State* state,
+                                           string* error,
+                                           bool* result) const {
+  *result = false;
+  return EvalStatus::kSucceeded;
+}
+
+// This will return immediately with |EvalStatus::kSucceeded| and set
+// |result|==|false|
+EvalStatus AndroidThingsPolicy::P2PEnabledChanged(EvaluationContext* ec,
+                                                  State* state,
+                                                  string* error,
+                                                  bool* result,
+                                                  bool prev_result) const {
+  *result = false;
+  return EvalStatus::kSucceeded;
+}
+
+}  // namespace chromeos_update_manager
diff --git a/update_manager/android_things_policy.h b/update_manager/android_things_policy.h
new file mode 100644
index 0000000..9fd8bc4
--- /dev/null
+++ b/update_manager/android_things_policy.h
@@ -0,0 +1,92 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_UPDATE_MANAGER_ANDROID_THINGS_POLICY_H_
+#define UPDATE_ENGINE_UPDATE_MANAGER_ANDROID_THINGS_POLICY_H_
+
+#include <string>
+
+#include "update_engine/update_manager/next_update_check_policy_impl.h"
+#include "update_engine/update_manager/policy_utils.h"
+
+namespace chromeos_update_manager {
+
+// AndroidThingsPolicy implements the policy-related logic used in
+// AndroidThings.
+class AndroidThingsPolicy : public Policy {
+ public:
+  AndroidThingsPolicy() = default;
+  ~AndroidThingsPolicy() override = default;
+
+  // Policy overrides.
+  EvalStatus UpdateCheckAllowed(EvaluationContext* ec,
+                                State* state,
+                                std::string* error,
+                                UpdateCheckParams* result) const override;
+
+  // Uses the |UpdateRestrictions| to determine if the download and apply can
+  // occur at this time.
+  EvalStatus UpdateCanBeApplied(
+      EvaluationContext* ec,
+      State* state,
+      std::string* error,
+      chromeos_update_engine::ErrorCode* result,
+      chromeos_update_engine::InstallPlan* install_plan) const override;
+
+  // Always returns |EvalStatus::kSucceeded|
+  EvalStatus UpdateCanStart(EvaluationContext* ec,
+                            State* state,
+                            std::string* error,
+                            UpdateDownloadParams* result,
+                            UpdateState update_state) const override;
+
+  // Always returns |EvalStatus::kSucceeded|
+  EvalStatus UpdateDownloadAllowed(EvaluationContext* ec,
+                                   State* state,
+                                   std::string* error,
+                                   bool* result) const override;
+
+  // P2P is always disabled.  Returns |result|==|false| and
+  // |EvalStatus::kSucceeded|
+  EvalStatus P2PEnabled(EvaluationContext* ec,
+                        State* state,
+                        std::string* error,
+                        bool* result) const override;
+
+  // This will return immediately with |EvalStatus::kSucceeded| and set
+  // |result|==|false|
+  EvalStatus P2PEnabledChanged(EvaluationContext* ec,
+                               State* state,
+                               std::string* error,
+                               bool* result,
+                               bool prev_result) const override;
+
+ protected:
+  // Policy override.
+  std::string PolicyName() const override { return "AndroidThingsPolicy"; }
+
+ private:
+  friend class UmAndroidThingsPolicyTest;
+  FRIEND_TEST(UmAndroidThingsPolicyTest, UpdateCheckAllowedWaitsForTheTimeout);
+
+  static const NextUpdateCheckPolicyConstants kNextUpdateCheckPolicyConstants;
+
+  DISALLOW_COPY_AND_ASSIGN(AndroidThingsPolicy);
+};
+
+}  // namespace chromeos_update_manager
+
+#endif  // UPDATE_ENGINE_UPDATE_MANAGER_ANDROID_THINGS_POLICY_H_
diff --git a/update_manager/android_things_policy_unittest.cc b/update_manager/android_things_policy_unittest.cc
new file mode 100644
index 0000000..8a50bc2
--- /dev/null
+++ b/update_manager/android_things_policy_unittest.cc
@@ -0,0 +1,188 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/update_manager/android_things_policy.h"
+
+#include <memory>
+
+#include "update_engine/update_manager/next_update_check_policy_impl.h"
+#include "update_engine/update_manager/policy_test_utils.h"
+
+using base::Time;
+using base::TimeDelta;
+using chromeos_update_engine::ErrorCode;
+using chromeos_update_engine::InstallPlan;
+
+namespace chromeos_update_manager {
+
+class UmAndroidThingsPolicyTest : public UmPolicyTestBase {
+ protected:
+  UmAndroidThingsPolicyTest() {
+    policy_ = std::make_unique<AndroidThingsPolicy>();
+  }
+
+  void SetUpDefaultState() override {
+    UmPolicyTestBase::SetUpDefaultState();
+
+    // For the purpose of the tests, this is an official build
+    fake_state_.system_provider()->var_is_official_build()->reset(
+        new bool(true));
+    // NOLINTNEXTLINE(readability/casting)
+    fake_state_.system_provider()->var_num_slots()->reset(new unsigned int(2));
+  }
+
+  // Configures the policy to return a desired value from UpdateCheckAllowed by
+  // faking the current wall clock time as needed. Restores the default state.
+  // This is used when testing policies that depend on this one.
+  virtual void SetUpdateCheckAllowed(bool allow_check) {
+    Time next_update_check;
+    CallMethodWithContext(&NextUpdateCheckTimePolicyImpl::NextUpdateCheckTime,
+                          &next_update_check,
+                          AndroidThingsPolicy::kNextUpdateCheckPolicyConstants);
+    SetUpDefaultState();
+    Time curr_time = next_update_check;
+    if (allow_check)
+      curr_time += TimeDelta::FromSeconds(1);
+    else
+      curr_time -= TimeDelta::FromSeconds(1);
+    fake_clock_.SetWallclockTime(curr_time);
+  }
+};
+
+TEST_F(UmAndroidThingsPolicyTest, UpdateCheckAllowedWaitsForTheTimeout) {
+  // We get the next update_check timestamp from the policy's private method
+  // and then we check the public method respects that value on the normal
+  // case.
+  Time next_update_check;
+  Time last_checked_time =
+      fake_clock_.GetWallclockTime() + TimeDelta::FromMinutes(1234);
+
+  LOG(INFO) << "last_checked_time: " << last_checked_time;
+  fake_state_.updater_provider()->var_last_checked_time()->reset(
+      new Time(last_checked_time));
+  CallMethodWithContext(&NextUpdateCheckTimePolicyImpl::NextUpdateCheckTime,
+                        &next_update_check,
+                        AndroidThingsPolicy::kNextUpdateCheckPolicyConstants);
+  LOG(INFO) << "Next check allowed at: " << next_update_check;
+
+  // Check that the policy blocks until the next_update_check is reached.
+  SetUpDefaultClock();
+  SetUpDefaultState();
+  fake_state_.updater_provider()->var_last_checked_time()->reset(
+      new Time(last_checked_time));
+  fake_clock_.SetWallclockTime(next_update_check - TimeDelta::FromSeconds(1));
+
+  UpdateCheckParams result;
+  ExpectPolicyStatus(
+      EvalStatus::kAskMeAgainLater, &Policy::UpdateCheckAllowed, &result);
+
+  SetUpDefaultClock();
+  SetUpDefaultState();
+  fake_state_.updater_provider()->var_last_checked_time()->reset(
+      new Time(last_checked_time));
+  fake_clock_.SetWallclockTime(next_update_check + TimeDelta::FromSeconds(1));
+  ExpectPolicyStatus(
+      EvalStatus::kSucceeded, &Policy::UpdateCheckAllowed, &result);
+  EXPECT_TRUE(result.updates_enabled);
+  EXPECT_FALSE(result.is_interactive);
+}
+
+TEST_F(UmAndroidThingsPolicyTest,
+       UpdateCheckAllowedUpdatesDisabledForUnofficialBuilds) {
+  // UpdateCheckAllowed should return kAskMeAgainLater if this is an unofficial
+  // build; we don't want periodic update checks on developer images.
+
+  fake_state_.system_provider()->var_is_official_build()->reset(
+      new bool(false));
+
+  UpdateCheckParams result;
+  ExpectPolicyStatus(
+      EvalStatus::kAskMeAgainLater, &Policy::UpdateCheckAllowed, &result);
+}
+
+TEST_F(UmAndroidThingsPolicyTest,
+       UpdateCheckAllowedUpdatesDisabledWhenNotEnoughSlotsAbUpdates) {
+  // UpdateCheckAllowed should return false (kSucceeded) if the image booted
+  // without enough slots to do A/B updates.
+
+  // NOLINTNEXTLINE(readability/casting)
+  fake_state_.system_provider()->var_num_slots()->reset(new unsigned int(1));
+
+  UpdateCheckParams result;
+  ExpectPolicyStatus(
+      EvalStatus::kSucceeded, &Policy::UpdateCheckAllowed, &result);
+  EXPECT_FALSE(result.updates_enabled);
+}
+
+TEST_F(UmAndroidThingsPolicyTest,
+       UpdateCheckAllowedForcedUpdateRequestedInteractive) {
+  // UpdateCheckAllowed should return true because a forced update request was
+  // signaled for an interactive update.
+
+  SetUpdateCheckAllowed(true);
+  fake_state_.updater_provider()->var_forced_update_requested()->reset(
+      new UpdateRequestStatus(UpdateRequestStatus::kInteractive));
+
+  UpdateCheckParams result;
+  ExpectPolicyStatus(
+      EvalStatus::kSucceeded, &Policy::UpdateCheckAllowed, &result);
+  EXPECT_TRUE(result.updates_enabled);
+  EXPECT_TRUE(result.is_interactive);
+}
+
+TEST_F(UmAndroidThingsPolicyTest,
+       UpdateCheckAllowedForcedUpdateRequestedPeriodic) {
+  // UpdateCheckAllowed should return true because a forced update request was
+  // signaled for a periodic check.
+
+  SetUpdateCheckAllowed(true);
+  fake_state_.updater_provider()->var_forced_update_requested()->reset(
+      new UpdateRequestStatus(UpdateRequestStatus::kPeriodic));
+
+  UpdateCheckParams result;
+  ExpectPolicyStatus(
+      EvalStatus::kSucceeded, &Policy::UpdateCheckAllowed, &result);
+  EXPECT_TRUE(result.updates_enabled);
+  EXPECT_FALSE(result.is_interactive);
+}
+
+TEST_F(UmAndroidThingsPolicyTest, UpdateCanBeAppliedOk) {
+  // UpdateCanBeApplied should return kSucceeded in the base case
+
+  InstallPlan plan;
+  ErrorCode result;
+  ExpectPolicyStatus(
+      EvalStatus::kSucceeded, &Policy::UpdateCanBeApplied, &result, &plan);
+
+  EXPECT_EQ(ErrorCode::kSuccess, result);
+}
+
+TEST_F(UmAndroidThingsPolicyTest, UpdateCanBeAppliedRestricted) {
+  // UpdateCanBeApplied should return kOmahaUpdateDeferredPerPolicy in
+  // when the restricted flag is set in the Updater.
+
+  fake_state_.updater_provider()->var_update_restrictions()->reset(
+      new UpdateRestrictions(UpdateRestrictions::kRestrictDownloading));
+
+  InstallPlan plan;
+  ErrorCode result;
+  ExpectPolicyStatus(
+      EvalStatus::kSucceeded, &Policy::UpdateCanBeApplied, &result, &plan);
+
+  EXPECT_EQ(ErrorCode::kOmahaUpdateDeferredPerPolicy, result);
+}
+
+}  // namespace chromeos_update_manager
diff --git a/update_manager/api_restricted_downloads_policy_impl.cc b/update_manager/api_restricted_downloads_policy_impl.cc
new file mode 100644
index 0000000..d413cca
--- /dev/null
+++ b/update_manager/api_restricted_downloads_policy_impl.cc
@@ -0,0 +1,47 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/update_manager/api_restricted_downloads_policy_impl.h"
+
+using chromeos_update_engine::ErrorCode;
+using std::string;
+using std::vector;
+
+namespace chromeos_update_manager {
+
+// Allow the API to restrict the downloading of updates.
+EvalStatus ApiRestrictedDownloadsPolicyImpl::UpdateCanBeApplied(
+    EvaluationContext* ec,
+    State* state,
+    std::string* error,
+    ErrorCode* result,
+    chromeos_update_engine::InstallPlan* install_plan) const {
+  // Next, check to see if updates can be applied (in general).
+  const UpdateRestrictions* update_restrictions_p =
+      ec->GetValue(state->updater_provider()->var_update_restrictions());
+  if (update_restrictions_p) {
+    if (*update_restrictions_p & UpdateRestrictions::kRestrictDownloading) {
+      *result = ErrorCode::kOmahaUpdateDeferredPerPolicy;
+      return EvalStatus::kSucceeded;
+    }
+  }
+
+  // The API isn't restricting downloads, so implicitly allow them to happen
+  // but don't explicitly return success from this policy implementation.
+  return EvalStatus::kContinue;
+}
+
+}  // namespace chromeos_update_manager
diff --git a/update_manager/api_restricted_downloads_policy_impl.h b/update_manager/api_restricted_downloads_policy_impl.h
new file mode 100644
index 0000000..21457a5
--- /dev/null
+++ b/update_manager/api_restricted_downloads_policy_impl.h
@@ -0,0 +1,51 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_UPDATE_MANAGER_API_RESTRICTED_DOWNLOADS_POLICY_IMPL_H_
+#define UPDATE_ENGINE_UPDATE_MANAGER_API_RESTRICTED_DOWNLOADS_POLICY_IMPL_H_
+
+#include <string>
+
+#include "update_engine/update_manager/policy_utils.h"
+
+namespace chromeos_update_manager {
+
+// Allow the API to restrict the downloading of updates.
+class ApiRestrictedDownloadsPolicyImpl : public PolicyImplBase {
+ public:
+  ApiRestrictedDownloadsPolicyImpl() = default;
+  ~ApiRestrictedDownloadsPolicyImpl() override = default;
+
+  // Policy overrides.
+  EvalStatus UpdateCanBeApplied(
+      EvaluationContext* ec,
+      State* state,
+      std::string* error,
+      chromeos_update_engine::ErrorCode* result,
+      chromeos_update_engine::InstallPlan* install_plan) const override;
+
+ protected:
+  std::string PolicyName() const override {
+    return "ApiRestrictedDownloadsPolicyImpl";
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ApiRestrictedDownloadsPolicyImpl);
+};
+
+}  // namespace chromeos_update_manager
+
+#endif  // UPDATE_ENGINE_UPDATE_MANAGER_API_RESTRICTED_DOWNLOADS_POLICY_IMPL_H_
diff --git a/update_manager/boxed_value.cc b/update_manager/boxed_value.cc
index 9758d33..a437c02 100644
--- a/update_manager/boxed_value.cc
+++ b/update_manager/boxed_value.cc
@@ -176,4 +176,19 @@
   return "Unknown";
 }
 
+template <>
+string BoxedValue::ValuePrinter<UpdateRestrictions>(const void* value) {
+  const UpdateRestrictions* val =
+      reinterpret_cast<const UpdateRestrictions*>(value);
+
+  if (*val == UpdateRestrictions::kNone) {
+    return "None";
+  }
+  string retval = "Flags:";
+  if (*val & kRestrictDownloading) {
+    retval += " RestrictDownloading";
+  }
+  return retval;
+}
+
 }  // namespace chromeos_update_manager
diff --git a/update_manager/boxed_value_unittest.cc b/update_manager/boxed_value_unittest.cc
index 2a086a6..4aeaec8 100644
--- a/update_manager/boxed_value_unittest.cc
+++ b/update_manager/boxed_value_unittest.cc
@@ -21,6 +21,7 @@
 #include <map>
 #include <set>
 #include <string>
+#include <utility>
 
 #include <base/strings/stringprintf.h>
 #include <base/time/time.h>
@@ -231,4 +232,14 @@
   EXPECT_EQ("DeleterMarker:true", value.ToString());
 }
 
+TEST(UmBoxedValueTest, UpdateRestrictionsToString) {
+  EXPECT_EQ(
+      "None",
+      BoxedValue(new UpdateRestrictions(UpdateRestrictions::kNone)).ToString());
+  EXPECT_EQ("Flags: RestrictDownloading",
+            BoxedValue(new UpdateRestrictions(
+                           UpdateRestrictions::kRestrictDownloading))
+                .ToString());
+}
+
 }  // namespace chromeos_update_manager
diff --git a/update_manager/chromeos_policy.cc b/update_manager/chromeos_policy.cc
index 81a169f..b32b626 100644
--- a/update_manager/chromeos_policy.cc
+++ b/update_manager/chromeos_policy.cc
@@ -36,6 +36,7 @@
 using chromeos_update_engine::ConnectionTethering;
 using chromeos_update_engine::ConnectionType;
 using chromeos_update_engine::ErrorCode;
+using chromeos_update_engine::InstallPlan;
 using std::get;
 using std::max;
 using std::min;
@@ -135,6 +136,7 @@
     case ErrorCode::kOmahaRequestXMLHasEntityDecl:
     case ErrorCode::kFilesystemVerifierError:
     case ErrorCode::kUserCanceled:
+    case ErrorCode::kUpdatedButNotActive:
       LOG(INFO) << "Not changing URL index or failure count due to error "
                 << chromeos_update_engine::utils::ErrorCodeToString(err_code)
                 << " (" << static_cast<int>(err_code) << ")";
@@ -324,6 +326,15 @@
   return EvalStatus::kSucceeded;
 }
 
+EvalStatus ChromeOSPolicy::UpdateCanBeApplied(EvaluationContext* ec,
+                                              State* state,
+                                              std::string* error,
+                                              ErrorCode* result,
+                                              InstallPlan* install_plan) const {
+  *result = ErrorCode::kSuccess;
+  return EvalStatus::kSucceeded;
+}
+
 EvalStatus ChromeOSPolicy::UpdateCanStart(
     EvaluationContext* ec,
     State* state,
diff --git a/update_manager/chromeos_policy.h b/update_manager/chromeos_policy.h
index b4370c4..283bedc 100644
--- a/update_manager/chromeos_policy.h
+++ b/update_manager/chromeos_policy.h
@@ -59,6 +59,13 @@
       EvaluationContext* ec, State* state, std::string* error,
       UpdateCheckParams* result) const override;
 
+  EvalStatus UpdateCanBeApplied(
+      EvaluationContext* ec,
+      State* state,
+      std::string* error,
+      chromeos_update_engine::ErrorCode* result,
+      chromeos_update_engine::InstallPlan* install_plan) const override;
+
   EvalStatus UpdateCanStart(
       EvaluationContext* ec,
       State* state,
diff --git a/update_manager/chromeos_policy_unittest.cc b/update_manager/chromeos_policy_unittest.cc
index 0c38700..63fa0f7 100644
--- a/update_manager/chromeos_policy_unittest.cc
+++ b/update_manager/chromeos_policy_unittest.cc
@@ -93,6 +93,7 @@
         new bool(true));
     fake_state_.system_provider()->var_is_oobe_complete()->reset(
         new bool(true));
+    // NOLINTNEXTLINE(readability/casting)
     fake_state_.system_provider()->var_num_slots()->reset(new unsigned int(2));
 
     // Connection is wifi, untethered.
@@ -418,10 +419,11 @@
 }
 
 TEST_F(UmChromeOSPolicyTest,
-       UpdateCheckAllowedUpdatesDisabledForRemovableBootDevice) {
+       UpdateCheckAllowedUpdatesDisabledWhenNotEnoughSlotsAbUpdates) {
   // UpdateCheckAllowed should return false (kSucceeded) if the image booted
-  // from a removable device.
+  // without enough slots to do A/B updates.
 
+  // NOLINTNEXTLINE(readability/casting)
   fake_state_.system_provider()->var_num_slots()->reset(new unsigned int(1));
 
   UpdateCheckParams result;
diff --git a/update_manager/default_policy.cc b/update_manager/default_policy.cc
index 9a5ce7e..5da1520 100644
--- a/update_manager/default_policy.cc
+++ b/update_manager/default_policy.cc
@@ -16,6 +16,9 @@
 
 #include "update_engine/update_manager/default_policy.h"
 
+using chromeos_update_engine::ErrorCode;
+using chromeos_update_engine::InstallPlan;
+
 namespace {
 
 // A fixed minimum interval between consecutive allowed update checks. This
@@ -53,6 +56,15 @@
   return EvalStatus::kAskMeAgainLater;
 }
 
+EvalStatus DefaultPolicy::UpdateCanBeApplied(EvaluationContext* ec,
+                                             State* state,
+                                             std::string* error,
+                                             ErrorCode* result,
+                                             InstallPlan* install_plan) const {
+  *result = ErrorCode::kSuccess;
+  return EvalStatus::kSucceeded;
+}
+
 EvalStatus DefaultPolicy::UpdateCanStart(
     EvaluationContext* ec,
     State* state,
diff --git a/update_manager/default_policy.h b/update_manager/default_policy.h
index 3f41178..136ca35 100644
--- a/update_manager/default_policy.h
+++ b/update_manager/default_policy.h
@@ -69,6 +69,13 @@
       EvaluationContext* ec, State* state, std::string* error,
       UpdateCheckParams* result) const override;
 
+  EvalStatus UpdateCanBeApplied(
+      EvaluationContext* ec,
+      State* state,
+      std::string* error,
+      chromeos_update_engine::ErrorCode* result,
+      chromeos_update_engine::InstallPlan* install_plan) const override;
+
   EvalStatus UpdateCanStart(
       EvaluationContext* ec, State* state, std::string* error,
       UpdateDownloadParams* result,
diff --git a/update_manager/enough_slots_ab_updates_policy_impl.cc b/update_manager/enough_slots_ab_updates_policy_impl.cc
new file mode 100644
index 0000000..70f15d4
--- /dev/null
+++ b/update_manager/enough_slots_ab_updates_policy_impl.cc
@@ -0,0 +1,38 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/update_manager/enough_slots_ab_updates_policy_impl.h"
+
+namespace chromeos_update_manager {
+
+// Do not perform any updates if booted from removable device. This decision
+// is final.
+EvalStatus EnoughSlotsAbUpdatesPolicyImpl::UpdateCheckAllowed(
+    EvaluationContext* ec,
+    State* state,
+    std::string* error,
+    UpdateCheckParams* result) const {
+  const auto* num_slots_p =
+      ec->GetValue(state->system_provider()->var_num_slots());
+  if (num_slots_p == nullptr || *num_slots_p < 2) {
+    LOG(INFO) << "Not enough slots for A/B updates, disabling update checks.";
+    result->updates_enabled = false;
+    return EvalStatus::kSucceeded;
+  }
+  return EvalStatus::kContinue;
+}
+
+}  // namespace chromeos_update_manager
diff --git a/update_manager/enough_slots_ab_updates_policy_impl.h b/update_manager/enough_slots_ab_updates_policy_impl.h
new file mode 100644
index 0000000..1d45389
--- /dev/null
+++ b/update_manager/enough_slots_ab_updates_policy_impl.h
@@ -0,0 +1,49 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_UPDATE_MANAGER_ENOUGH_SLOTS_AB_UPDATES_POLICY_IMPL_H_
+#define UPDATE_ENGINE_UPDATE_MANAGER_ENOUGH_SLOTS_AB_UPDATES_POLICY_IMPL_H_
+
+#include <string>
+
+#include "update_engine/update_manager/policy_utils.h"
+
+namespace chromeos_update_manager {
+
+// Do not perform any updates if booted from removable device.
+class EnoughSlotsAbUpdatesPolicyImpl : public PolicyImplBase {
+ public:
+  EnoughSlotsAbUpdatesPolicyImpl() = default;
+  ~EnoughSlotsAbUpdatesPolicyImpl() override = default;
+
+  // Policy overrides.
+  EvalStatus UpdateCheckAllowed(EvaluationContext* ec,
+                                State* state,
+                                std::string* error,
+                                UpdateCheckParams* result) const override;
+
+ protected:
+  std::string PolicyName() const override {
+    return "EnoughSlotsAbUpdatesPolicyImpl";
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(EnoughSlotsAbUpdatesPolicyImpl);
+};
+
+}  // namespace chromeos_update_manager
+
+#endif  // UPDATE_ENGINE_UPDATE_MANAGER_ENOUGH_SLOTS_AB_UPDATES_POLICY_IMPL_H_
diff --git a/update_manager/evaluation_context.cc b/update_manager/evaluation_context.cc
index 98238f2..b6c7b91 100644
--- a/update_manager/evaluation_context.cc
+++ b/update_manager/evaluation_context.cc
@@ -24,7 +24,6 @@
 #include <base/bind.h>
 #include <base/json/json_writer.h>
 #include <base/location.h>
-#include <base/memory/ptr_util.h>
 #include <base/strings/string_util.h>
 #include <base/values.h>
 
@@ -229,7 +228,7 @@
 }
 
 string EvaluationContext::DumpContext() const {
-  auto variables = base::MakeUnique<base::DictionaryValue>();
+  auto variables = std::make_unique<base::DictionaryValue>();
   for (auto& it : value_cache_) {
     variables->SetString(it.first->GetName(), it.second.ToString());
   }
diff --git a/update_manager/fake_updater_provider.h b/update_manager/fake_updater_provider.h
index 44389f4..7295765 100644
--- a/update_manager/fake_updater_provider.h
+++ b/update_manager/fake_updater_provider.h
@@ -41,19 +41,15 @@
     return &var_update_completed_time_;
   }
 
-  FakeVariable<double>* var_progress() override {
-    return &var_progress_;
-  }
+  FakeVariable<double>* var_progress() override { return &var_progress_; }
 
-  FakeVariable<Stage>* var_stage() override {
-    return &var_stage_;
-  }
+  FakeVariable<Stage>* var_stage() override { return &var_stage_; }
 
   FakeVariable<std::string>* var_new_version() override {
     return &var_new_version_;
   }
 
-  FakeVariable<int64_t>* var_payload_size() override {
+  FakeVariable<uint64_t>* var_payload_size() override {
     return &var_payload_size_;
   }
 
@@ -65,9 +61,7 @@
     return &var_new_channel_;
   }
 
-  FakeVariable<bool>* var_p2p_enabled() override {
-    return &var_p2p_enabled_;
-  }
+  FakeVariable<bool>* var_p2p_enabled() override { return &var_p2p_enabled_; }
 
   FakeVariable<bool>* var_cellular_enabled() override {
     return &var_cellular_enabled_;
@@ -85,42 +79,35 @@
     return &var_forced_update_requested_;
   }
 
+  FakeVariable<UpdateRestrictions>* var_update_restrictions() override {
+    return &var_update_restrictions_;
+  }
+
  private:
-  FakeVariable<base::Time>
-      var_updater_started_time_{  // NOLINT(whitespace/braces)
-    "updater_started_time", kVariableModePoll};
-  FakeVariable<base::Time> var_last_checked_time_{  // NOLINT(whitespace/braces)
-    "last_checked_time", kVariableModePoll};
-  FakeVariable<base::Time>
-      var_update_completed_time_{  // NOLINT(whitespace/braces)
-    "update_completed_time", kVariableModePoll};
-  FakeVariable<double> var_progress_{  // NOLINT(whitespace/braces)
-    "progress", kVariableModePoll};
-  FakeVariable<Stage> var_stage_{  // NOLINT(whitespace/braces)
-    "stage", kVariableModePoll};
-  FakeVariable<std::string> var_new_version_{  // NOLINT(whitespace/braces)
-    "new_version", kVariableModePoll};
-  FakeVariable<int64_t> var_payload_size_{  // NOLINT(whitespace/braces)
-    "payload_size", kVariableModePoll};
-  FakeVariable<std::string> var_curr_channel_{  // NOLINT(whitespace/braces)
-    "curr_channel", kVariableModePoll};
-  FakeVariable<std::string> var_new_channel_{  // NOLINT(whitespace/braces)
-    "new_channel", kVariableModePoll};
-  FakeVariable<bool> var_p2p_enabled_{// NOLINT(whitespace/braces)
-                                      "p2p_enabled",
-                                      kVariableModeAsync};
-  FakeVariable<bool> var_cellular_enabled_{// NOLINT(whitespace/braces)
-                                           "cellular_enabled",
+  FakeVariable<base::Time> var_updater_started_time_{"updater_started_time",
+                                                     kVariableModePoll};
+  FakeVariable<base::Time> var_last_checked_time_{"last_checked_time",
+                                                  kVariableModePoll};
+  FakeVariable<base::Time> var_update_completed_time_{"update_completed_time",
+                                                      kVariableModePoll};
+  FakeVariable<double> var_progress_{"progress", kVariableModePoll};
+  FakeVariable<Stage> var_stage_{"stage", kVariableModePoll};
+  FakeVariable<std::string> var_new_version_{"new_version", kVariableModePoll};
+  FakeVariable<uint64_t> var_payload_size_{"payload_size", kVariableModePoll};
+  FakeVariable<std::string> var_curr_channel_{"curr_channel",
+                                              kVariableModePoll};
+  FakeVariable<std::string> var_new_channel_{"new_channel", kVariableModePoll};
+  FakeVariable<bool> var_p2p_enabled_{"p2p_enabled", kVariableModeAsync};
+  FakeVariable<bool> var_cellular_enabled_{"cellular_enabled",
                                            kVariableModeAsync};
-  FakeVariable<unsigned int>
-      var_consecutive_failed_update_checks_{  // NOLINT(whitespace/braces)
-    "consecutive_failed_update_checks", kVariableModePoll};
-  FakeVariable<unsigned int>
-      var_server_dictated_poll_interval_{  // NOLINT(whitespace/braces)
-    "server_dictated_poll_interval", kVariableModePoll};
-  FakeVariable<UpdateRequestStatus>
-      var_forced_update_requested_{  // NOLINT(whitespace/braces)
-    "forced_update_requested", kVariableModeAsync};
+  FakeVariable<unsigned int> var_consecutive_failed_update_checks_{
+      "consecutive_failed_update_checks", kVariableModePoll};
+  FakeVariable<unsigned int> var_server_dictated_poll_interval_{
+      "server_dictated_poll_interval", kVariableModePoll};
+  FakeVariable<UpdateRequestStatus> var_forced_update_requested_{
+      "forced_update_requested", kVariableModeAsync};
+  FakeVariable<UpdateRestrictions> var_update_restrictions_{
+      "update_restrictions", kVariableModePoll};
 
   DISALLOW_COPY_AND_ASSIGN(FakeUpdaterProvider);
 };
diff --git a/update_manager/interactive_update_policy_impl.cc b/update_manager/interactive_update_policy_impl.cc
new file mode 100644
index 0000000..df7f17b
--- /dev/null
+++ b/update_manager/interactive_update_policy_impl.cc
@@ -0,0 +1,44 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/update_manager/interactive_update_policy_impl.h"
+
+namespace chromeos_update_manager {
+
+// Check to see if an interactive update was requested.
+EvalStatus InteractiveUpdatePolicyImpl::UpdateCheckAllowed(
+    EvaluationContext* ec,
+    State* state,
+    std::string* error,
+    UpdateCheckParams* result) const {
+  UpdaterProvider* const updater_provider = state->updater_provider();
+
+  // First, check to see if an interactive update was requested.
+  const UpdateRequestStatus* forced_update_requested_p =
+      ec->GetValue(updater_provider->var_forced_update_requested());
+  if (forced_update_requested_p != nullptr &&
+      *forced_update_requested_p != UpdateRequestStatus::kNone) {
+    result->is_interactive =
+        (*forced_update_requested_p == UpdateRequestStatus::kInteractive);
+    LOG(INFO) << "Forced update signaled ("
+              << (result->is_interactive ? "interactive" : "periodic")
+              << "), allowing update check.";
+    return EvalStatus::kSucceeded;
+  }
+  return EvalStatus::kContinue;
+}
+
+}  // namespace chromeos_update_manager
diff --git a/update_manager/interactive_update_policy_impl.h b/update_manager/interactive_update_policy_impl.h
new file mode 100644
index 0000000..a431456
--- /dev/null
+++ b/update_manager/interactive_update_policy_impl.h
@@ -0,0 +1,49 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_UPDATE_MANAGER_INTERACTIVE_UPDATE_POLICY_IMPL_H_
+#define UPDATE_ENGINE_UPDATE_MANAGER_INTERACTIVE_UPDATE_POLICY_IMPL_H_
+
+#include <string>
+
+#include "update_engine/update_manager/policy_utils.h"
+
+namespace chromeos_update_manager {
+
+// Check to see if an interactive update was requested.
+class InteractiveUpdatePolicyImpl : public PolicyImplBase {
+ public:
+  InteractiveUpdatePolicyImpl() = default;
+  ~InteractiveUpdatePolicyImpl() override = default;
+
+  // Policy overrides.
+  EvalStatus UpdateCheckAllowed(EvaluationContext* ec,
+                                State* state,
+                                std::string* error,
+                                UpdateCheckParams* result) const override;
+
+ protected:
+  std::string PolicyName() const override {
+    return "InteractiveUpdatePolicyImpl";
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(InteractiveUpdatePolicyImpl);
+};
+
+}  // namespace chromeos_update_manager
+
+#endif  // UPDATE_ENGINE_UPDATE_MANAGER_OFFICIAL_BUILD_CHECK_POLICY_IMPL_H_
diff --git a/update_manager/mock_policy.h b/update_manager/mock_policy.h
index 14470e9..8060bf8 100644
--- a/update_manager/mock_policy.h
+++ b/update_manager/mock_policy.h
@@ -36,6 +36,11 @@
                                       testing::_))
         .WillByDefault(testing::Invoke(
                 &default_policy_, &DefaultPolicy::UpdateCheckAllowed));
+    ON_CALL(*this,
+            UpdateCanBeApplied(
+                testing::_, testing::_, testing::_, testing::_, testing::_))
+        .WillByDefault(testing::Invoke(&default_policy_,
+                                       &DefaultPolicy::UpdateCanBeApplied));
     ON_CALL(*this, UpdateCanStart(testing::_, testing::_, testing::_,
                                   testing::_, testing::_))
         .WillByDefault(testing::Invoke(
@@ -61,6 +66,13 @@
                      EvalStatus(EvaluationContext*, State*, std::string*,
                                 UpdateCheckParams*));
 
+  MOCK_CONST_METHOD5(UpdateCanBeApplied,
+                     EvalStatus(EvaluationContext*,
+                                State*,
+                                std::string*,
+                                chromeos_update_engine::ErrorCode*,
+                                chromeos_update_engine::InstallPlan*));
+
   MOCK_CONST_METHOD5(UpdateCanStart,
                      EvalStatus(EvaluationContext*, State*, std::string*,
                                 UpdateDownloadParams*, UpdateState));
diff --git a/update_manager/next_update_check_policy_impl.cc b/update_manager/next_update_check_policy_impl.cc
new file mode 100644
index 0000000..6f9748e
--- /dev/null
+++ b/update_manager/next_update_check_policy_impl.cc
@@ -0,0 +1,150 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/update_manager/next_update_check_policy_impl.h"
+
+#include <algorithm>
+
+#include "update_engine/common/utils.h"
+
+using base::Time;
+using base::TimeDelta;
+using std::max;
+using std::string;
+
+namespace chromeos_update_manager {
+
+NextUpdateCheckTimePolicyImpl::NextUpdateCheckTimePolicyImpl(
+    const NextUpdateCheckPolicyConstants& constants)
+    : policy_constants_(constants) {}
+
+EvalStatus NextUpdateCheckTimePolicyImpl::UpdateCheckAllowed(
+    EvaluationContext* ec,
+    State* state,
+    string* error,
+    UpdateCheckParams* result) const {
+  // Ensure that periodic update checks are timed properly.
+  Time next_update_check;
+
+  if (NextUpdateCheckTime(
+          ec, state, error, &next_update_check, policy_constants_) !=
+      EvalStatus::kSucceeded) {
+    return EvalStatus::kFailed;
+  }
+  if (!ec->IsWallclockTimeGreaterThan(next_update_check)) {
+    LOG(INFO) << "Periodic check interval not satisfied, blocking until "
+              << chromeos_update_engine::utils::ToString(next_update_check);
+    return EvalStatus::kAskMeAgainLater;
+  }
+
+  return EvalStatus::kContinue;
+}
+
+EvalStatus NextUpdateCheckTimePolicyImpl::NextUpdateCheckTime(
+    EvaluationContext* ec,
+    State* state,
+    string* error,
+    Time* next_update_check,
+    const NextUpdateCheckPolicyConstants& constants) {
+  UpdaterProvider* const updater_provider = state->updater_provider();
+
+  // Don't check for updates too often. We limit the update checks to once every
+  // some interval. The interval is kTimeoutInitialInterval the first time and
+  // kTimeoutPeriodicInterval for the subsequent update checks. If the update
+  // check fails, we increase the interval between the update checks
+  // exponentially until kTimeoutMaxBackoffInterval. Finally, to avoid having
+  // many chromebooks running update checks at the exact same time, we add some
+  // fuzz to the interval.
+  const Time* updater_started_time =
+      ec->GetValue(updater_provider->var_updater_started_time());
+  POLICY_CHECK_VALUE_AND_FAIL(updater_started_time, error);
+
+  const Time* last_checked_time =
+      ec->GetValue(updater_provider->var_last_checked_time());
+
+  const auto* seed = ec->GetValue(state->random_provider()->var_seed());
+  POLICY_CHECK_VALUE_AND_FAIL(seed, error);
+
+  PRNG prng(*seed);
+
+  // If this is the first attempt, compute and return an initial value.
+  if (last_checked_time == nullptr ||
+      *last_checked_time < *updater_started_time) {
+    *next_update_check = *updater_started_time +
+                         FuzzedInterval(&prng,
+                                        constants.timeout_initial_interval,
+                                        constants.timeout_regular_fuzz);
+    return EvalStatus::kSucceeded;
+  }
+
+  // Check whether the server is enforcing a poll interval; if not, this value
+  // will be zero.
+  const unsigned int* server_dictated_poll_interval =
+      ec->GetValue(updater_provider->var_server_dictated_poll_interval());
+  POLICY_CHECK_VALUE_AND_FAIL(server_dictated_poll_interval, error);
+
+  int interval = *server_dictated_poll_interval;
+  int fuzz = 0;
+
+  // If no poll interval was dictated by server compute a back-off period,
+  // starting from a predetermined base periodic interval and increasing
+  // exponentially by the number of consecutive failed attempts.
+  if (interval == 0) {
+    const unsigned int* consecutive_failed_update_checks =
+        ec->GetValue(updater_provider->var_consecutive_failed_update_checks());
+    POLICY_CHECK_VALUE_AND_FAIL(consecutive_failed_update_checks, error);
+
+    interval = constants.timeout_periodic_interval;
+    unsigned int num_failures = *consecutive_failed_update_checks;
+    while (interval < constants.timeout_max_backoff_interval && num_failures) {
+      interval *= 2;
+      num_failures--;
+    }
+  }
+
+  // We cannot back off longer than the predetermined maximum interval.
+  if (interval > constants.timeout_max_backoff_interval)
+    interval = constants.timeout_max_backoff_interval;
+
+  // We cannot back off shorter than the predetermined periodic interval. Also,
+  // in this case set the fuzz to a predetermined regular value.
+  if (interval <= constants.timeout_periodic_interval) {
+    interval = constants.timeout_periodic_interval;
+    fuzz = constants.timeout_regular_fuzz;
+  }
+
+  // If not otherwise determined, defer to a fuzz of +/-(interval / 2).
+  if (fuzz == 0)
+    fuzz = interval;
+
+  *next_update_check =
+      *last_checked_time + FuzzedInterval(&prng, interval, fuzz);
+  return EvalStatus::kSucceeded;
+}
+
+TimeDelta NextUpdateCheckTimePolicyImpl::FuzzedInterval(PRNG* prng,
+                                                        int interval,
+                                                        int fuzz) {
+  DCHECK_GE(interval, 0);
+  DCHECK_GE(fuzz, 0);
+  int half_fuzz = fuzz / 2;
+  // This guarantees the output interval is non negative.
+  int interval_min = max(interval - half_fuzz, 0);
+  int interval_max = interval + half_fuzz;
+  return TimeDelta::FromSeconds(prng->RandMinMax(interval_min, interval_max));
+}
+
+}  // namespace chromeos_update_manager
diff --git a/update_manager/next_update_check_policy_impl.h b/update_manager/next_update_check_policy_impl.h
new file mode 100644
index 0000000..291ea0f
--- /dev/null
+++ b/update_manager/next_update_check_policy_impl.h
@@ -0,0 +1,98 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_UPDATE_MANAGER_NEXT_UPDATE_CHECK_POLICY_IMPL_H_
+#define UPDATE_ENGINE_UPDATE_MANAGER_NEXT_UPDATE_CHECK_POLICY_IMPL_H_
+
+#include <string>
+
+#include <base/time/time.h>
+
+#include "update_engine/update_manager/policy_utils.h"
+#include "update_engine/update_manager/prng.h"
+
+namespace chromeos_update_manager {
+
+// Constants that are provided to the policy implementation.
+struct NextUpdateCheckPolicyConstants {
+  // Default update check timeout interval/fuzz values used to compute the
+  // NextUpdateCheckTime(), in seconds. Actual fuzz is within +/- half of the
+  // indicated value.
+  int timeout_initial_interval;
+  int timeout_periodic_interval;
+  int timeout_max_backoff_interval;
+  int timeout_regular_fuzz;
+
+  // Maximum update attempt backoff interval and fuzz.
+  int attempt_backoff_max_interval_in_days;
+  int attempt_backoff_fuzz_in_hours;
+};
+
+// Ensure that periodic update checks are timed properly.
+class NextUpdateCheckTimePolicyImpl : public PolicyImplBase {
+ public:
+  explicit NextUpdateCheckTimePolicyImpl(
+      const NextUpdateCheckPolicyConstants& constants);
+
+  // Policy overrides.
+  EvalStatus UpdateCheckAllowed(EvaluationContext* ec,
+                                State* state,
+                                std::string* error,
+                                UpdateCheckParams* result) const override;
+
+  // A private policy implementation returning the wallclock timestamp when
+  // the next update check should happen.
+  // TODO(garnold) We should probably change that to infer a monotonic
+  // timestamp, which will make the update check intervals more resilient to
+  // clock skews. Might require switching some of the variables exported by the
+  // UpdaterProvider to report monotonic time, as well.
+  //
+  // NOTE:
+  // Exposed as a public static so that it's logic can be used to test
+  // Policy implementations that utilize this fragment for their
+  // timing, without needing to list them all with FRIEND_TEST (so that
+  // those Policy implementations can exist without modifying this
+  // class's definition.
+  //
+  // The output value from this method (|next_update_check|), isn't
+  // available via the UpdateCheckParams |result| of the Policy
+  // method, and so this timing logic needs to be otherwise exposed.
+  static EvalStatus NextUpdateCheckTime(
+      EvaluationContext* ec,
+      State* state,
+      std::string* error,
+      base::Time* next_update_check,
+      const NextUpdateCheckPolicyConstants& constants);
+
+  // Returns a TimeDelta based on the provided |interval| seconds +/- half
+  // |fuzz| seconds. The return value is guaranteed to be a non-negative
+  // TimeDelta.
+  static base::TimeDelta FuzzedInterval(PRNG* prng, int interval, int fuzz);
+
+ protected:
+  std::string PolicyName() const override {
+    return "NextUpdateCheckTimePolicyImpl";
+  }
+
+ private:
+  const NextUpdateCheckPolicyConstants policy_constants_;
+
+  DISALLOW_COPY_AND_ASSIGN(NextUpdateCheckTimePolicyImpl);
+};
+
+}  // namespace chromeos_update_manager
+
+#endif  // UPDATE_ENGINE_UPDATE_MANAGER_NEXT_UPDATE_CHECK_POLICY_IMPL_H_
diff --git a/update_manager/next_update_check_policy_impl_unittest.cc b/update_manager/next_update_check_policy_impl_unittest.cc
new file mode 100644
index 0000000..58aff66
--- /dev/null
+++ b/update_manager/next_update_check_policy_impl_unittest.cc
@@ -0,0 +1,163 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/update_manager/next_update_check_policy_impl.h"
+
+#include <memory>
+
+#include "update_engine/update_manager/policy_test_utils.h"
+
+using base::Time;
+using base::TimeDelta;
+using std::string;
+
+namespace chromeos_update_manager {
+
+const NextUpdateCheckPolicyConstants policy_test_constants = {
+    // these are specifically NOT the values used by real Policy
+    // implementations.
+    .timeout_initial_interval = 3 * 60,
+    .timeout_periodic_interval = 2 * 60 * 60,
+    .timeout_max_backoff_interval = 8 * 60 * 60,
+    .timeout_regular_fuzz = 5 * 60,
+    .attempt_backoff_max_interval_in_days = 12,
+    .attempt_backoff_fuzz_in_hours = 10,
+};
+
+class UmNextUpdateCheckTimePolicyImplTest : public UmPolicyTestBase {
+ protected:
+  UmNextUpdateCheckTimePolicyImplTest() {
+    policy_ =
+        std::make_unique<NextUpdateCheckTimePolicyImpl>(policy_test_constants);
+  }
+};
+
+TEST_F(UmNextUpdateCheckTimePolicyImplTest,
+       FirstCheckIsAtMostInitialIntervalAfterStart) {
+  Time next_update_check;
+
+  // Set the last update time so it'll appear as if this is a first update check
+  // in the lifetime of the current updater.
+  fake_state_.updater_provider()->var_last_checked_time()->reset(
+      new Time(fake_clock_.GetWallclockTime() - TimeDelta::FromMinutes(10)));
+
+  CallMethodWithContext(&NextUpdateCheckTimePolicyImpl::NextUpdateCheckTime,
+                        &next_update_check,
+                        policy_test_constants);
+
+  EXPECT_LE(fake_clock_.GetWallclockTime(), next_update_check);
+  EXPECT_GE(fake_clock_.GetWallclockTime() +
+                TimeDelta::FromSeconds(
+                    policy_test_constants.timeout_initial_interval +
+                    policy_test_constants.timeout_regular_fuzz / 2),
+            next_update_check);
+}
+
+TEST_F(UmNextUpdateCheckTimePolicyImplTest, RecurringCheckBaseIntervalAndFuzz) {
+  // Ensure that we're using the correct interval (kPeriodicInterval) and fuzz
+  // (ktimeout_regular_fuzz) as base values for period updates.
+  Time next_update_check;
+
+  CallMethodWithContext(&NextUpdateCheckTimePolicyImpl::NextUpdateCheckTime,
+                        &next_update_check,
+                        policy_test_constants);
+
+  EXPECT_LE(fake_clock_.GetWallclockTime() +
+                TimeDelta::FromSeconds(
+                    policy_test_constants.timeout_periodic_interval -
+                    policy_test_constants.timeout_regular_fuzz / 2),
+            next_update_check);
+  EXPECT_GE(fake_clock_.GetWallclockTime() +
+                TimeDelta::FromSeconds(
+                    policy_test_constants.timeout_periodic_interval +
+                    policy_test_constants.timeout_regular_fuzz / 2),
+            next_update_check);
+}
+
+TEST_F(UmNextUpdateCheckTimePolicyImplTest,
+       RecurringCheckBackoffIntervalAndFuzz) {
+  // Ensure that we're properly backing off and fuzzing in the presence of
+  // failed updates attempts.
+  Time next_update_check;
+
+  fake_state_.updater_provider()->var_consecutive_failed_update_checks()->reset(
+      new unsigned int{2});
+
+  ExpectStatus(EvalStatus::kSucceeded,
+               NextUpdateCheckTimePolicyImpl::NextUpdateCheckTime,
+               &next_update_check,
+               policy_test_constants);
+
+  int expected_interval = policy_test_constants.timeout_periodic_interval * 4;
+  EXPECT_LE(
+      fake_clock_.GetWallclockTime() +
+          TimeDelta::FromSeconds(expected_interval - expected_interval / 2),
+      next_update_check);
+  EXPECT_GE(
+      fake_clock_.GetWallclockTime() +
+          TimeDelta::FromSeconds(expected_interval + expected_interval / 2),
+      next_update_check);
+}
+
+TEST_F(UmNextUpdateCheckTimePolicyImplTest,
+       RecurringCheckServerDictatedPollInterval) {
+  // Policy honors the server provided check poll interval.
+  Time next_update_check;
+
+  const auto kInterval = policy_test_constants.timeout_periodic_interval * 4;
+  fake_state_.updater_provider()->var_server_dictated_poll_interval()->reset(
+      new unsigned int(kInterval));  // NOLINT(readability/casting)
+  // We should not be backing off in this case.
+  fake_state_.updater_provider()->var_consecutive_failed_update_checks()->reset(
+      new unsigned int(2));  // NOLINT(readability/casting)
+
+  ExpectStatus(EvalStatus::kSucceeded,
+               &NextUpdateCheckTimePolicyImpl::NextUpdateCheckTime,
+               &next_update_check,
+               policy_test_constants);
+
+  EXPECT_LE(fake_clock_.GetWallclockTime() +
+                TimeDelta::FromSeconds(kInterval - kInterval / 2),
+            next_update_check);
+  EXPECT_GE(fake_clock_.GetWallclockTime() +
+                TimeDelta::FromSeconds(kInterval + kInterval / 2),
+            next_update_check);
+}
+
+TEST_F(UmNextUpdateCheckTimePolicyImplTest, ExponentialBackoffIsCapped) {
+  Time next_update_check;
+
+  fake_state_.updater_provider()->var_consecutive_failed_update_checks()->reset(
+      new unsigned int(100));  // NOLINT(readability/casting)
+
+  ExpectStatus(EvalStatus::kSucceeded,
+               &NextUpdateCheckTimePolicyImpl::NextUpdateCheckTime,
+               &next_update_check,
+               policy_test_constants);
+
+  EXPECT_LE(fake_clock_.GetWallclockTime() +
+                TimeDelta::FromSeconds(
+                    policy_test_constants.timeout_max_backoff_interval -
+                    policy_test_constants.timeout_max_backoff_interval / 2),
+            next_update_check);
+  EXPECT_GE(fake_clock_.GetWallclockTime() +
+                TimeDelta::FromSeconds(
+                    policy_test_constants.timeout_max_backoff_interval +
+                    policy_test_constants.timeout_max_backoff_interval / 2),
+            next_update_check);
+}
+
+}  // namespace chromeos_update_manager
diff --git a/update_manager/official_build_check_policy_impl.cc b/update_manager/official_build_check_policy_impl.cc
new file mode 100644
index 0000000..096f7bf
--- /dev/null
+++ b/update_manager/official_build_check_policy_impl.cc
@@ -0,0 +1,36 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/update_manager/official_build_check_policy_impl.h"
+
+namespace chromeos_update_manager {
+
+// Unofficial builds should not perform periodic update checks.
+EvalStatus OnlyUpdateOfficialBuildsPolicyImpl::UpdateCheckAllowed(
+    EvaluationContext* ec,
+    State* state,
+    std::string* error,
+    UpdateCheckParams* result) const {
+  const bool* is_official_build_p =
+      ec->GetValue(state->system_provider()->var_is_official_build());
+  if (is_official_build_p != nullptr && !(*is_official_build_p)) {
+    LOG(INFO) << "Unofficial build, blocking periodic update checks.";
+    return EvalStatus::kAskMeAgainLater;
+  }
+  return EvalStatus::kContinue;
+}
+
+}  // namespace chromeos_update_manager
diff --git a/update_manager/official_build_check_policy_impl.h b/update_manager/official_build_check_policy_impl.h
new file mode 100644
index 0000000..6257209
--- /dev/null
+++ b/update_manager/official_build_check_policy_impl.h
@@ -0,0 +1,49 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_UPDATE_MANAGER_OFFICIAL_BUILD_CHECK_POLICY_IMPL_H_
+#define UPDATE_ENGINE_UPDATE_MANAGER_OFFICIAL_BUILD_CHECK_POLICY_IMPL_H_
+
+#include <string>
+
+#include "update_engine/update_manager/policy_utils.h"
+
+namespace chromeos_update_manager {
+
+// Unofficial builds should not perform periodic update checks.
+class OnlyUpdateOfficialBuildsPolicyImpl : public PolicyImplBase {
+ public:
+  OnlyUpdateOfficialBuildsPolicyImpl() = default;
+  ~OnlyUpdateOfficialBuildsPolicyImpl() override = default;
+
+  // Policy overrides.
+  EvalStatus UpdateCheckAllowed(EvaluationContext* ec,
+                                State* state,
+                                std::string* error,
+                                UpdateCheckParams* result) const override;
+
+ protected:
+  std::string PolicyName() const override {
+    return "OnlyUpdateOfficialBuildsPolicyImpl";
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(OnlyUpdateOfficialBuildsPolicyImpl);
+};
+
+}  // namespace chromeos_update_manager
+
+#endif  // UPDATE_ENGINE_UPDATE_MANAGER_OFFICIAL_BUILD_CHECK_POLICY_IMPL_H_
diff --git a/update_manager/policy.cc b/update_manager/policy.cc
index 151c225..5f79a68 100644
--- a/update_manager/policy.cc
+++ b/update_manager/policy.cc
@@ -30,6 +30,8 @@
       return "kSucceeded";
     case EvalStatus::kAskMeAgainLater:
       return "kAskMeAgainLater";
+    case EvalStatus::kContinue:
+      return "kContinue";
   }
   return "Invalid";
 }
diff --git a/update_manager/policy.h b/update_manager/policy.h
index fae1494..b60c4da 100644
--- a/update_manager/policy.h
+++ b/update_manager/policy.h
@@ -22,6 +22,7 @@
 #include <vector>
 
 #include "update_engine/common/error_code.h"
+#include "update_engine/payload_consumer/install_plan.h"
 #include "update_engine/update_manager/evaluation_context.h"
 #include "update_engine/update_manager/state.h"
 
@@ -32,6 +33,7 @@
   kFailed,
   kSucceeded,
   kAskMeAgainLater,
+  kContinue,
 };
 
 std::string ToString(EvalStatus status);
@@ -204,6 +206,9 @@
     if (reinterpret_cast<typeof(&Policy::UpdateCheckAllowed)>(
             policy_method) == &Policy::UpdateCheckAllowed)
       return class_name + "UpdateCheckAllowed";
+    if (reinterpret_cast<typeof(&Policy::UpdateCanBeApplied)>(policy_method) ==
+        &Policy::UpdateCanBeApplied)
+      return class_name + "UpdateCanBeApplied";
     if (reinterpret_cast<typeof(&Policy::UpdateCanStart)>(
             policy_method) == &Policy::UpdateCanStart)
       return class_name + "UpdateCanStart";
@@ -235,6 +240,17 @@
       EvaluationContext* ec, State* state, std::string* error,
       UpdateCheckParams* result) const = 0;
 
+  // UpdateCanBeApplied returns whether the given |install_plan| can be acted
+  // on at this time.  The reason for not applying is returned in |result|.
+  // The Policy may modify the passed-in |install_plan|, based on the
+  // implementation in the Policy and values provided by the EvaluationContext.
+  virtual EvalStatus UpdateCanBeApplied(
+      EvaluationContext* ec,
+      State* state,
+      std::string* error,
+      chromeos_update_engine::ErrorCode* result,
+      chromeos_update_engine::InstallPlan* install_plan) const = 0;
+
   // Returns EvalStatus::kSucceeded if either an update can start being
   // processed, or the attempt needs to be aborted. In cases where the update
   // needs to wait for some condition to be satisfied, but none of the values
diff --git a/update_manager/policy_test_utils.cc b/update_manager/policy_test_utils.cc
new file mode 100644
index 0000000..fbfcb82
--- /dev/null
+++ b/update_manager/policy_test_utils.cc
@@ -0,0 +1,110 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/update_manager/policy_test_utils.h"
+
+#include <memory>
+#include <tuple>
+#include <vector>
+
+#include "update_engine/update_manager/next_update_check_policy_impl.h"
+
+using base::Time;
+using base::TimeDelta;
+using chromeos_update_engine::ErrorCode;
+using std::string;
+using std::tuple;
+using std::vector;
+
+namespace chromeos_update_manager {
+
+void UmPolicyTestBase::SetUp() {
+  loop_.SetAsCurrent();
+  SetUpDefaultClock();
+  eval_ctx_ = new EvaluationContext(&fake_clock_, TimeDelta::FromSeconds(5));
+  SetUpDefaultState();
+}
+
+void UmPolicyTestBase::TearDown() {
+  EXPECT_FALSE(loop_.PendingTasks());
+}
+
+// Sets the clock to fixed values.
+void UmPolicyTestBase::SetUpDefaultClock() {
+  fake_clock_.SetMonotonicTime(Time::FromInternalValue(12345678L));
+  fake_clock_.SetWallclockTime(Time::FromInternalValue(12345678901234L));
+}
+
+void UmPolicyTestBase::SetUpDefaultState() {
+  fake_state_.updater_provider()->var_updater_started_time()->reset(
+      new Time(fake_clock_.GetWallclockTime()));
+  fake_state_.updater_provider()->var_last_checked_time()->reset(
+      new Time(fake_clock_.GetWallclockTime()));
+  fake_state_.updater_provider()->var_consecutive_failed_update_checks()->reset(
+      new unsigned int(0));  // NOLINT(readability/casting)
+  fake_state_.updater_provider()->var_server_dictated_poll_interval()->reset(
+      new unsigned int(0));  // NOLINT(readability/casting)
+  fake_state_.updater_provider()->var_forced_update_requested()->reset(
+      new UpdateRequestStatus{UpdateRequestStatus::kNone});
+
+  // Chosen by fair dice roll.  Guaranteed to be random.
+  fake_state_.random_provider()->var_seed()->reset(new uint64_t(4));
+}
+
+// Returns a default UpdateState structure:
+UpdateState UmPolicyTestBase::GetDefaultUpdateState(
+    TimeDelta first_seen_period) {
+  Time first_seen_time = fake_clock_.GetWallclockTime() - first_seen_period;
+  UpdateState update_state = UpdateState();
+
+  // This is a non-interactive check returning a delta payload, seen for the
+  // first time (|first_seen_period| ago). Clearly, there were no failed
+  // attempts so far.
+  update_state.is_interactive = false;
+  update_state.is_delta_payload = false;
+  update_state.first_seen = first_seen_time;
+  update_state.num_checks = 1;
+  update_state.num_failures = 0;
+  update_state.failures_last_updated = Time();  // Needs to be zero.
+  // There's a single HTTP download URL with a maximum of 10 retries.
+  update_state.download_urls = vector<string>{"http://fake/url/"};
+  update_state.download_errors_max = 10;
+  // Download was never attempted.
+  update_state.last_download_url_idx = -1;
+  update_state.last_download_url_num_errors = 0;
+  // There were no download errors.
+  update_state.download_errors = vector<tuple<int, ErrorCode, Time>>();
+  // P2P is not disabled by Omaha.
+  update_state.p2p_downloading_disabled = false;
+  update_state.p2p_sharing_disabled = false;
+  // P2P was not attempted.
+  update_state.p2p_num_attempts = 0;
+  update_state.p2p_first_attempted = Time();
+  // No active backoff period, backoff is not disabled by Omaha.
+  update_state.backoff_expiry = Time();
+  update_state.is_backoff_disabled = false;
+  // There is no active scattering wait period (max 7 days allowed) nor check
+  // threshold (none allowed).
+  update_state.scatter_wait_period = TimeDelta();
+  update_state.scatter_check_threshold = 0;
+  update_state.scatter_wait_period_max = TimeDelta::FromDays(7);
+  update_state.scatter_check_threshold_min = 0;
+  update_state.scatter_check_threshold_max = 0;
+
+  return update_state;
+}
+
+}  // namespace chromeos_update_manager
diff --git a/update_manager/policy_test_utils.h b/update_manager/policy_test_utils.h
new file mode 100644
index 0000000..5b93f7b
--- /dev/null
+++ b/update_manager/policy_test_utils.h
@@ -0,0 +1,99 @@
+//
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_UPDATE_MANAGER_POLICY_TEST_UTILS_H_
+#define UPDATE_ENGINE_UPDATE_MANAGER_POLICY_TEST_UTILS_H_
+
+#include <memory>
+#include <string>
+
+#include <base/time/time.h>
+#include <brillo/message_loops/fake_message_loop.h>
+#include <gtest/gtest.h>
+
+#include "update_engine/common/fake_clock.h"
+#include "update_engine/update_manager/evaluation_context.h"
+#include "update_engine/update_manager/fake_state.h"
+#include "update_engine/update_manager/policy_utils.h"
+
+namespace chromeos_update_manager {
+
+class UmPolicyTestBase : public ::testing::Test {
+ protected:
+  UmPolicyTestBase() = default;
+
+  void SetUp() override;
+
+  void TearDown() override;
+
+  // Sets the clock to fixed values.
+  virtual void SetUpDefaultClock();
+
+  // Sets up the default state in fake_state_.  override to add Policy-specific
+  // items, but only after calling this class's implementation.
+  virtual void SetUpDefaultState();
+
+  // Returns a default UpdateState structure:
+  virtual UpdateState GetDefaultUpdateState(base::TimeDelta first_seen_period);
+
+  // Runs the passed |method| after resetting the EvaluationContext and expects
+  // it to return the |expected| return value.
+  template <typename T, typename R, typename... Args>
+  void ExpectStatus(EvalStatus expected, T method, R* result, Args... args) {
+    std::string error = "<None>";
+    eval_ctx_->ResetEvaluation();
+    EXPECT_EQ(expected,
+              (*method)(eval_ctx_.get(), &fake_state_, &error, result, args...))
+        << "Returned error: " << error
+        << "\nEvaluation context: " << eval_ctx_->DumpContext();
+  }
+
+  // Runs the passed |method| after resetting the EvaluationContext, in order
+  // to use the method to get a value for other testing (doesn't validate the
+  // return value, just returns it).
+  template <typename T, typename R, typename... Args>
+  EvalStatus CallMethodWithContext(T method, R* result, Args... args) {
+    std::string error = "<None>";
+    eval_ctx_->ResetEvaluation();
+    return (*method)(eval_ctx_.get(), &fake_state_, &error, result, args...);
+  }
+
+  // Runs the passed |policy_method| on the framework policy and expects it to
+  // return the |expected| return value.
+  template <typename T, typename R, typename... Args>
+  void ExpectPolicyStatus(EvalStatus expected,
+                          T policy_method,
+                          R* result,
+                          Args... args) {
+    std::string error = "<None>";
+    eval_ctx_->ResetEvaluation();
+    EXPECT_EQ(expected,
+              (policy_.get()->*policy_method)(
+                  eval_ctx_.get(), &fake_state_, &error, result, args...))
+        << "Returned error: " << error
+        << "\nEvaluation context: " << eval_ctx_->DumpContext();
+  }
+
+  brillo::FakeMessageLoop loop_{nullptr};
+  chromeos_update_engine::FakeClock fake_clock_;
+  FakeState fake_state_;
+  scoped_refptr<EvaluationContext> eval_ctx_;
+  std::unique_ptr<Policy> policy_;
+};
+
+}  // namespace chromeos_update_manager
+
+#endif  // UPDATE_ENGINE_UPDATE_MANAGER_POLICY_TEST_UTILS_H_
diff --git a/update_manager/policy_utils.h b/update_manager/policy_utils.h
index 960987e..eaf9ee9 100644
--- a/update_manager/policy_utils.h
+++ b/update_manager/policy_utils.h
@@ -17,6 +17,9 @@
 #ifndef UPDATE_ENGINE_UPDATE_MANAGER_POLICY_UTILS_H_
 #define UPDATE_ENGINE_UPDATE_MANAGER_POLICY_UTILS_H_
 
+#include <string>
+#include <vector>
+
 #include "update_engine/update_manager/policy.h"
 
 // Checks that the passed pointer value is not null, returning kFailed on the
@@ -35,4 +38,84 @@
       } \
     } while (false)
 
+namespace chromeos_update_manager {
+
+// Call the passed-in Policy method on a series of Policy implementations, until
+// one of them renders a decision by returning a value other than
+// |EvalStatus::kContinue|.
+template <typename T, typename R, typename... Args>
+EvalStatus ConsultPolicies(const std::vector<Policy const*> policies,
+                           T policy_method,
+                           EvaluationContext* ec,
+                           State* state,
+                           std::string* error,
+                           R* result,
+                           Args... args) {
+  for (auto policy : policies) {
+    EvalStatus status =
+        (policy->*policy_method)(ec, state, error, result, args...);
+    if (status != EvalStatus::kContinue) {
+      LOG(INFO) << "decision by " << policy->PolicyRequestName(policy_method);
+      return status;
+    }
+  }
+  return EvalStatus::kContinue;
+}
+
+// Base class implementation that returns |EvalStatus::kContinue| for all
+// decisions, to be used as a base-class for various Policy facets that only
+// pertain to certain situations. This might be better folded into Policy
+// instead of using pure-virtual methods on that class.
+class PolicyImplBase : public Policy {
+ public:
+  // Policy overrides.
+  EvalStatus UpdateCheckAllowed(EvaluationContext* ec,
+                                State* state,
+                                std::string* error,
+                                UpdateCheckParams* result) const override {
+    return EvalStatus::kContinue;
+  };
+
+  EvalStatus UpdateCanBeApplied(
+      EvaluationContext* ec,
+      State* state,
+      std::string* error,
+      chromeos_update_engine::ErrorCode* result,
+      chromeos_update_engine::InstallPlan* install_plan) const override {
+    return EvalStatus::kContinue;
+  };
+
+  EvalStatus UpdateCanStart(EvaluationContext* ec,
+                            State* state,
+                            std::string* error,
+                            UpdateDownloadParams* result,
+                            UpdateState update_state) const override {
+    return EvalStatus::kContinue;
+  };
+
+  EvalStatus UpdateDownloadAllowed(EvaluationContext* ec,
+                                   State* state,
+                                   std::string* error,
+                                   bool* result) const override {
+    return EvalStatus::kContinue;
+  };
+
+  EvalStatus P2PEnabled(EvaluationContext* ec,
+                        State* state,
+                        std::string* error,
+                        bool* result) const override {
+    return EvalStatus::kContinue;
+  };
+
+  EvalStatus P2PEnabledChanged(EvaluationContext* ec,
+                               State* state,
+                               std::string* error,
+                               bool* result,
+                               bool prev_result) const override {
+    return EvalStatus::kContinue;
+  };
+};
+
+}  // namespace chromeos_update_manager
+
 #endif  // UPDATE_ENGINE_UPDATE_MANAGER_POLICY_UTILS_H_
diff --git a/update_manager/real_device_policy_provider_unittest.cc b/update_manager/real_device_policy_provider_unittest.cc
index 71c95bb..167cbd9 100644
--- a/update_manager/real_device_policy_provider_unittest.cc
+++ b/update_manager/real_device_policy_provider_unittest.cc
@@ -18,7 +18,7 @@
 
 #include <memory>
 
-#include <brillo/make_unique_ptr.h>
+#include <base/memory/ptr_util.h>
 #include <brillo/message_loops/fake_message_loop.h>
 #include <brillo/message_loops/message_loop.h>
 #include <brillo/message_loops/message_loop_utils.h>
@@ -63,8 +63,7 @@
     auto session_manager_proxy_mock =
         new org::chromium::SessionManagerInterfaceProxyMock();
     provider_.reset(new RealDevicePolicyProvider(
-        brillo::make_unique_ptr(session_manager_proxy_mock),
-        &mock_policy_provider_));
+        base::WrapUnique(session_manager_proxy_mock), &mock_policy_provider_));
 #else
     provider_.reset(new RealDevicePolicyProvider(&mock_policy_provider_));
 #endif  // USE_DBUS
diff --git a/update_manager/real_shill_provider_unittest.cc b/update_manager/real_shill_provider_unittest.cc
index e821dc7..6506923 100644
--- a/update_manager/real_shill_provider_unittest.cc
+++ b/update_manager/real_shill_provider_unittest.cc
@@ -18,8 +18,8 @@
 #include <memory>
 #include <utility>
 
+#include <base/memory/ptr_util.h>
 #include <base/time/time.h>
-#include <brillo/make_unique_ptr.h>
 #include <brillo/message_loops/fake_message_loop.h>
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
@@ -94,7 +94,9 @@
     now_exp.minute = 5;
     now_exp.second = 33;
     now_exp.millisecond = 675;
-    return Time::FromLocalExploded(now_exp);
+    Time time;
+    ignore_result(Time::FromLocalExploded(now_exp, &time));
+    return time;
   }
 
   Time ConnChangedTime() {
@@ -261,9 +263,9 @@
   EXPECT_CALL(*service_proxy_mock, GetProperties(_, _, _))
       .WillOnce(DoAll(SetArgPointee<0>(reply_dict), Return(true)));
 
-  fake_shill_proxy_->SetServiceForPath(
-      dbus::ObjectPath(service_path),
-      brillo::make_unique_ptr(service_proxy_mock));
+  fake_shill_proxy_->SetServiceForPath(dbus::ObjectPath(service_path),
+                                       base::WrapUnique(service_proxy_mock));
+
   return service_proxy_mock;
 }
 
diff --git a/update_manager/real_system_provider.cc b/update_manager/real_system_provider.cc
index 9b968ca..fdf7e86 100644
--- a/update_manager/real_system_provider.cc
+++ b/update_manager/real_system_provider.cc
@@ -20,9 +20,9 @@
 #include <base/callback.h>
 #include <base/logging.h>
 #include <base/time/time.h>
-#if USE_LIBCROS
+#if USE_CHROME_KIOSK_APP
 #include <libcros/dbus-proxies.h>
-#endif
+#endif  // USE_CHROME_KIOSK_APP
 
 #include "update_engine/common/utils.h"
 #include "update_engine/update_manager/generic_variables.h"
@@ -124,7 +124,7 @@
 
 bool RealSystemProvider::GetKioskAppRequiredPlatformVersion(
     string* required_platform_version) {
-#if USE_LIBCROS
+#if USE_CHROME_KIOSK_APP
   brillo::ErrorPtr error;
   if (!libcros_proxy_->GetKioskAppRequiredPlatformVersion(
           required_platform_version, &error)) {
@@ -132,7 +132,7 @@
     required_platform_version->clear();
     return false;
   }
-#endif
+#endif  // USE_CHROME_KIOSK_APP
 
   return true;
 }
diff --git a/update_manager/real_system_provider.h b/update_manager/real_system_provider.h
index a62e1ae..80a8615 100644
--- a/update_manager/real_system_provider.h
+++ b/update_manager/real_system_provider.h
@@ -40,8 +40,12 @@
       chromeos_update_engine::BootControlInterface* boot_control,
       org::chromium::LibCrosServiceInterfaceProxyInterface* libcros_proxy)
       : hardware_(hardware),
+#if USE_CHROME_KIOSK_APP
         boot_control_(boot_control),
         libcros_proxy_(libcros_proxy) {}
+#else
+        boot_control_(boot_control) {}
+#endif  // USE_CHROME_KIOSK_APP
 
   // Initializes the provider and returns whether it succeeded.
   bool Init();
@@ -78,8 +82,9 @@
 
   chromeos_update_engine::HardwareInterface* const hardware_;
   chromeos_update_engine::BootControlInterface* const boot_control_;
-  org::chromium::LibCrosServiceInterfaceProxyInterface* const libcros_proxy_
-      ALLOW_UNUSED_TYPE;
+#if USE_CHROME_KIOSK_APP
+  org::chromium::LibCrosServiceInterfaceProxyInterface* const libcros_proxy_;
+#endif  // USE_CHROME_KIOSK_APP
 
   DISALLOW_COPY_AND_ASSIGN(RealSystemProvider);
 };
diff --git a/update_manager/real_system_provider_unittest.cc b/update_manager/real_system_provider_unittest.cc
index 821a6cc..103a35f 100644
--- a/update_manager/real_system_provider_unittest.cc
+++ b/update_manager/real_system_provider_unittest.cc
@@ -19,37 +19,36 @@
 #include <memory>
 
 #include <base/time/time.h>
-#include <brillo/make_unique_ptr.h>
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
 #include "update_engine/common/fake_boot_control.h"
 #include "update_engine/common/fake_hardware.h"
 #include "update_engine/update_manager/umtest_utils.h"
-#if USE_LIBCROS
+#if USE_CHROME_KIOSK_APP
 #include "libcros/dbus-proxies.h"
 #include "libcros/dbus-proxy-mocks.h"
 
 using org::chromium::LibCrosServiceInterfaceProxyMock;
-#endif  // USE_LIBCROS
+#endif  // USE_CHROME_KIOSK_APP
 using std::unique_ptr;
 using testing::_;
 using testing::DoAll;
 using testing::Return;
 using testing::SetArgPointee;
 
-#if USE_LIBCROS
+#if USE_CHROME_KIOSK_APP
 namespace {
 const char kRequiredPlatformVersion[] ="1234.0.0";
 }  // namespace
-#endif  // USE_LIBCROS
+#endif  // USE_CHROME_KIOSK_APP
 
 namespace chromeos_update_manager {
 
 class UmRealSystemProviderTest : public ::testing::Test {
  protected:
   void SetUp() override {
-#if USE_LIBCROS
+#if USE_CHROME_KIOSK_APP
     libcros_proxy_mock_.reset(new LibCrosServiceInterfaceProxyMock());
     ON_CALL(*libcros_proxy_mock_,
             GetKioskAppRequiredPlatformVersion(_, _, _))
@@ -61,7 +60,7 @@
 #else
     provider_.reset(
         new RealSystemProvider(&fake_hardware_, &fake_boot_control_, nullptr));
-#endif  // USE_LIBCROS
+#endif  // USE_CHROME_KIOSK_APP
     EXPECT_TRUE(provider_->Init());
   }
 
@@ -69,9 +68,9 @@
   chromeos_update_engine::FakeBootControl fake_boot_control_;
   unique_ptr<RealSystemProvider> provider_;
 
-#if USE_LIBCROS
+#if USE_CHROME_KIOSK_APP
   unique_ptr<LibCrosServiceInterfaceProxyMock> libcros_proxy_mock_;
-#endif  // USE_LIBCROS
+#endif  // USE_CHROME_KIOSK_APP
 };
 
 TEST_F(UmRealSystemProviderTest, InitTest) {
@@ -91,7 +90,7 @@
   UmTestUtils::ExpectVariableHasValue(false, provider_->var_is_oobe_complete());
 }
 
-#if USE_LIBCROS
+#if USE_CHROME_KIOSK_APP
 TEST_F(UmRealSystemProviderTest, KioskRequiredPlatformVersion) {
   UmTestUtils::ExpectVariableHasValue(
       std::string(kRequiredPlatformVersion),
@@ -129,6 +128,6 @@
   UmTestUtils::ExpectVariableHasValue(
       std::string(), provider_->var_kiosk_required_platform_version());
 }
-#endif
+#endif  // USE_CHROME_KIOSK_APP
 
 }  // namespace chromeos_update_manager
diff --git a/update_manager/real_time_provider.cc b/update_manager/real_time_provider.cc
index ca3acad..db26816 100644
--- a/update_manager/real_time_provider.cc
+++ b/update_manager/real_time_provider.cc
@@ -43,7 +43,10 @@
     Time::Exploded now_exp;
     clock_->GetWallclockTime().LocalExplode(&now_exp);
     now_exp.hour = now_exp.minute = now_exp.second = now_exp.millisecond = 0;
-    return new Time(Time::FromLocalExploded(now_exp));
+    Time* now = new Time();
+    bool success = Time::FromLocalExploded(now_exp, now);
+    DCHECK(success);
+    return now;
   }
 
  private:
diff --git a/update_manager/real_time_provider_unittest.cc b/update_manager/real_time_provider_unittest.cc
index 0e1ef34..f8db30b 100644
--- a/update_manager/real_time_provider_unittest.cc
+++ b/update_manager/real_time_provider_unittest.cc
@@ -51,7 +51,9 @@
     now_exp.minute = 5;
     now_exp.second = 33;
     now_exp.millisecond = 675;
-    return Time::FromLocalExploded(now_exp);
+    Time time;
+    ignore_result(Time::FromLocalExploded(now_exp, &time));
+    return time;
   }
 
   FakeClock fake_clock_;
@@ -66,7 +68,8 @@
   exploded.minute = 0;
   exploded.second = 0;
   exploded.millisecond = 0;
-  const Time expected = Time::FromLocalExploded(exploded);
+  Time expected;
+  ignore_result(Time::FromLocalExploded(exploded, &expected));
 
   fake_clock_.SetWallclockTime(now);
   UmTestUtils::ExpectVariableHasValue(expected, provider_->var_curr_date());
diff --git a/update_manager/real_updater_provider.cc b/update_manager/real_updater_provider.cc
index 1a3e65a..050bd42 100644
--- a/update_manager/real_updater_provider.cc
+++ b/update_manager/real_updater_provider.cc
@@ -25,10 +25,12 @@
 #include <base/time/time.h>
 #include <update_engine/dbus-constants.h>
 
+#include "update_engine/client_library/include/update_engine/update_status.h"
 #include "update_engine/common/clock_interface.h"
 #include "update_engine/common/prefs.h"
 #include "update_engine/omaha_request_params.h"
 #include "update_engine/update_attempter.h"
+#include "update_engine/update_status_utils.h"
 
 using base::StringPrintf;
 using base::Time;
@@ -36,6 +38,8 @@
 using chromeos_update_engine::OmahaRequestParams;
 using chromeos_update_engine::SystemState;
 using std::string;
+using update_engine::UpdateAttemptFlags;
+using update_engine::UpdateEngineStatus;
 
 namespace chromeos_update_manager {
 
@@ -60,27 +64,32 @@
 class GetStatusHelper {
  public:
   GetStatusHelper(SystemState* system_state, string* errmsg) {
-    is_success_ = system_state->update_attempter()->GetStatus(
-        &last_checked_time_, &progress_, &update_status_, &new_version_,
-        &payload_size_);
-    if (!is_success_ && errmsg)
+    is_success_ =
+        system_state->update_attempter()->GetStatus(&update_engine_status_);
+    if (!is_success_ && errmsg) {
       *errmsg = "Failed to get a status update from the update engine";
+    }
   }
 
   inline bool is_success() { return is_success_; }
-  inline int64_t last_checked_time() { return last_checked_time_; }
-  inline double progress() { return progress_; }
-  inline const string& update_status() { return update_status_; }
-  inline const string& new_version() { return new_version_; }
-  inline int64_t payload_size() { return payload_size_; }
+  inline int64_t last_checked_time() {
+    return update_engine_status_.last_checked_time;
+  }
+  inline double progress() { return update_engine_status_.progress; }
+  inline const string update_status() {
+    return chromeos_update_engine::UpdateStatusToString(
+        update_engine_status_.status);
+  }
+  inline const string& new_version() {
+    return update_engine_status_.new_version;
+  }
+  inline uint64_t payload_size() {
+    return update_engine_status_.new_size_bytes;
+  }
 
  private:
   bool is_success_;
-  int64_t last_checked_time_;
-  double progress_;
-  string update_status_;
-  string new_version_;
-  int64_t payload_size_;
+  UpdateEngineStatus update_engine_status_;
 };
 
 // A variable reporting the time when a last update check was issued.
@@ -196,24 +205,18 @@
 };
 
 // A variable reporting the size of the update being processed in bytes.
-class PayloadSizeVariable : public UpdaterVariableBase<int64_t> {
+class PayloadSizeVariable : public UpdaterVariableBase<uint64_t> {
  public:
   PayloadSizeVariable(const string& name, SystemState* system_state)
-      : UpdaterVariableBase<int64_t>(name, kVariableModePoll, system_state) {}
+      : UpdaterVariableBase<uint64_t>(name, kVariableModePoll, system_state) {}
 
  private:
-  const int64_t* GetValue(TimeDelta /* timeout */, string* errmsg) override {
+  const uint64_t* GetValue(TimeDelta /* timeout */, string* errmsg) override {
     GetStatusHelper raw(system_state(), errmsg);
     if (!raw.is_success())
       return nullptr;
 
-    if (raw.payload_size() < 0) {
-      if (errmsg)
-        *errmsg = string("Invalid payload size: %" PRId64, raw.payload_size());
-      return nullptr;
-    }
-
-    return new int64_t(raw.payload_size());
+    return new uint64_t(raw.payload_size());
   }
 
   DISALLOW_COPY_AND_ASSIGN(PayloadSizeVariable);
@@ -414,40 +417,66 @@
   DISALLOW_COPY_AND_ASSIGN(ForcedUpdateRequestedVariable);
 };
 
+// A variable returning the current update restrictions that are in effect.
+class UpdateRestrictionsVariable
+    : public UpdaterVariableBase<UpdateRestrictions> {
+ public:
+  UpdateRestrictionsVariable(const string& name, SystemState* system_state)
+      : UpdaterVariableBase<UpdateRestrictions>(
+            name, kVariableModePoll, system_state) {}
+
+ private:
+  const UpdateRestrictions* GetValue(TimeDelta /* timeout */,
+                                     string* /* errmsg */) override {
+    UpdateAttemptFlags attempt_flags =
+        system_state()->update_attempter()->GetCurrentUpdateAttemptFlags();
+    UpdateRestrictions restriction_flags = UpdateRestrictions::kNone;
+    // Don't blindly copy the whole value, test and set bits that should
+    // transfer from one set of flags to the other.
+    if (attempt_flags & UpdateAttemptFlags::kFlagRestrictDownload) {
+      restriction_flags = static_cast<UpdateRestrictions>(
+          restriction_flags | UpdateRestrictions::kRestrictDownloading);
+    }
+
+    return new UpdateRestrictions(restriction_flags);
+  }
+
+  DISALLOW_COPY_AND_ASSIGN(UpdateRestrictionsVariable);
+};
+
 // RealUpdaterProvider methods.
 
 RealUpdaterProvider::RealUpdaterProvider(SystemState* system_state)
-  : system_state_(system_state),
-    var_updater_started_time_("updater_started_time",
-                              system_state->clock()->GetWallclockTime()),
-    var_last_checked_time_(
-        new LastCheckedTimeVariable("last_checked_time", system_state_)),
-    var_update_completed_time_(
-        new UpdateCompletedTimeVariable("update_completed_time",
-                                        system_state_)),
-    var_progress_(new ProgressVariable("progress", system_state_)),
-    var_stage_(new StageVariable("stage", system_state_)),
-    var_new_version_(new NewVersionVariable("new_version", system_state_)),
-    var_payload_size_(new PayloadSizeVariable("payload_size", system_state_)),
-    var_curr_channel_(new CurrChannelVariable("curr_channel", system_state_)),
-    var_new_channel_(new NewChannelVariable("new_channel", system_state_)),
-    var_p2p_enabled_(
-        new BooleanPrefVariable("p2p_enabled", system_state_->prefs(),
-                                chromeos_update_engine::kPrefsP2PEnabled,
-                                false)),
-    var_cellular_enabled_(
-        new BooleanPrefVariable(
-            "cellular_enabled", system_state_->prefs(),
-            chromeos_update_engine::kPrefsUpdateOverCellularPermission,
-            false)),
-    var_consecutive_failed_update_checks_(
-        new ConsecutiveFailedUpdateChecksVariable(
-            "consecutive_failed_update_checks", system_state_)),
-    var_server_dictated_poll_interval_(
-        new ServerDictatedPollIntervalVariable(
-            "server_dictated_poll_interval", system_state_)),
-    var_forced_update_requested_(
-        new ForcedUpdateRequestedVariable(
-            "forced_update_requested", system_state_)) {}
-
+    : system_state_(system_state),
+      var_updater_started_time_("updater_started_time",
+                                system_state->clock()->GetWallclockTime()),
+      var_last_checked_time_(
+          new LastCheckedTimeVariable("last_checked_time", system_state_)),
+      var_update_completed_time_(new UpdateCompletedTimeVariable(
+          "update_completed_time", system_state_)),
+      var_progress_(new ProgressVariable("progress", system_state_)),
+      var_stage_(new StageVariable("stage", system_state_)),
+      var_new_version_(new NewVersionVariable("new_version", system_state_)),
+      var_payload_size_(new PayloadSizeVariable("payload_size", system_state_)),
+      var_curr_channel_(new CurrChannelVariable("curr_channel", system_state_)),
+      var_new_channel_(new NewChannelVariable("new_channel", system_state_)),
+      var_p2p_enabled_(
+          new BooleanPrefVariable("p2p_enabled",
+                                  system_state_->prefs(),
+                                  chromeos_update_engine::kPrefsP2PEnabled,
+                                  false)),
+      var_cellular_enabled_(new BooleanPrefVariable(
+          "cellular_enabled",
+          system_state_->prefs(),
+          chromeos_update_engine::kPrefsUpdateOverCellularPermission,
+          false)),
+      var_consecutive_failed_update_checks_(
+          new ConsecutiveFailedUpdateChecksVariable(
+              "consecutive_failed_update_checks", system_state_)),
+      var_server_dictated_poll_interval_(new ServerDictatedPollIntervalVariable(
+          "server_dictated_poll_interval", system_state_)),
+      var_forced_update_requested_(new ForcedUpdateRequestedVariable(
+          "forced_update_requested", system_state_)),
+      var_update_restrictions_(new UpdateRestrictionsVariable(
+          "update_restrictions", system_state_)) {}
 }  // namespace chromeos_update_manager
diff --git a/update_manager/real_updater_provider.h b/update_manager/real_updater_provider.h
index b99bcc5..5e3e27b 100644
--- a/update_manager/real_updater_provider.h
+++ b/update_manager/real_updater_provider.h
@@ -64,7 +64,7 @@
     return var_new_version_.get();
   }
 
-  Variable<int64_t>* var_payload_size() override {
+  Variable<uint64_t>* var_payload_size() override {
     return var_payload_size_.get();
   }
 
@@ -96,6 +96,10 @@
     return var_forced_update_requested_.get();
   }
 
+  Variable<UpdateRestrictions>* var_update_restrictions() override {
+    return var_update_restrictions_.get();
+  }
+
  private:
   // A pointer to the update engine's system state aggregator.
   chromeos_update_engine::SystemState* system_state_;
@@ -107,7 +111,7 @@
   std::unique_ptr<Variable<double>> var_progress_;
   std::unique_ptr<Variable<Stage>> var_stage_;
   std::unique_ptr<Variable<std::string>> var_new_version_;
-  std::unique_ptr<Variable<int64_t>> var_payload_size_;
+  std::unique_ptr<Variable<uint64_t>> var_payload_size_;
   std::unique_ptr<Variable<std::string>> var_curr_channel_;
   std::unique_ptr<Variable<std::string>> var_new_channel_;
   std::unique_ptr<Variable<bool>> var_p2p_enabled_;
@@ -115,6 +119,7 @@
   std::unique_ptr<Variable<unsigned int>> var_consecutive_failed_update_checks_;
   std::unique_ptr<Variable<unsigned int>> var_server_dictated_poll_interval_;
   std::unique_ptr<Variable<UpdateRequestStatus>> var_forced_update_requested_;
+  std::unique_ptr<Variable<UpdateRestrictions>> var_update_restrictions_;
 
   DISALLOW_COPY_AND_ASSIGN(RealUpdaterProvider);
 };
diff --git a/update_manager/real_updater_provider_unittest.cc b/update_manager/real_updater_provider_unittest.cc
index 14eb30b..b653885 100644
--- a/update_manager/real_updater_provider_unittest.cc
+++ b/update_manager/real_updater_provider_unittest.cc
@@ -38,9 +38,11 @@
 using chromeos_update_engine::OmahaRequestParams;
 using std::string;
 using std::unique_ptr;
+using testing::_;
+using testing::DoAll;
 using testing::Return;
 using testing::SetArgPointee;
-using testing::_;
+using update_engine::UpdateAttemptFlags;
 
 namespace {
 
@@ -55,7 +57,9 @@
   now_exp.minute = 5;
   now_exp.second = 33;
   now_exp.millisecond = 675;
-  return Time::FromLocalExploded(now_exp);
+  Time time;
+  ignore_result(Time::FromLocalExploded(now_exp, &time));
+  return time;
 }
 
 // Rounds down a timestamp to the nearest second. This is useful when faking
@@ -64,7 +68,29 @@
   Time::Exploded exp;
   time.LocalExplode(&exp);
   exp.millisecond = 0;
-  return Time::FromLocalExploded(exp);
+  Time rounded_time;
+  ignore_result(Time::FromLocalExploded(exp, &rounded_time));
+  return rounded_time;
+}
+
+ACTION_P(ActionSetUpdateEngineStatusLastCheckedTime, time) {
+  arg0->last_checked_time = time;
+};
+
+ACTION_P(ActionSetUpdateEngineStatusProgress, progress) {
+  arg0->progress = progress;
+};
+
+ACTION_P(ActionSetUpdateEngineStatusStatus, status) {
+  arg0->status = status;
+}
+
+ACTION_P(ActionSetUpdateEngineStatusNewVersion, new_version) {
+  arg0->new_version = new_version;
+}
+
+ACTION_P(ActionSetUpdateEngineStatusNewSizeBytes, new_size_bytes) {
+  arg0->new_size_bytes = new_size_bytes;
 }
 
 }  // namespace
@@ -116,225 +142,189 @@
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetLastCheckedTimeOkay) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<0>(FixedTime().ToTimeT()), Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(
+          ActionSetUpdateEngineStatusLastCheckedTime(FixedTime().ToTimeT()),
+          Return(true)));
   UmTestUtils::ExpectVariableHasValue(RoundedToSecond(FixedTime()),
                                       provider_->var_last_checked_time());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetLastCheckedTimeFailNoValue) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
       .WillOnce(Return(false));
   UmTestUtils::ExpectVariableNotSet(provider_->var_last_checked_time());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetProgressOkayMin) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<1>(0.0), Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusProgress(0.0), Return(true)));
   UmTestUtils::ExpectVariableHasValue(0.0, provider_->var_progress());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetProgressOkayMid) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<1>(0.3), Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusProgress(0.3), Return(true)));
   UmTestUtils::ExpectVariableHasValue(0.3, provider_->var_progress());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetProgressOkayMax) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<1>(1.0), Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusProgress(1.0), Return(true)));
   UmTestUtils::ExpectVariableHasValue(1.0, provider_->var_progress());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetProgressFailNoValue) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
       .WillOnce(Return(false));
   UmTestUtils::ExpectVariableNotSet(provider_->var_progress());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetProgressFailTooSmall) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<1>(-2.0), Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusProgress(-2.0), Return(true)));
   UmTestUtils::ExpectVariableNotSet(provider_->var_progress());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetProgressFailTooBig) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<1>(2.0), Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusProgress(2.0), Return(true)));
   UmTestUtils::ExpectVariableNotSet(provider_->var_progress());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetStageOkayIdle) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<2>(update_engine::kUpdateStatusIdle),
-                      Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(
+          ActionSetUpdateEngineStatusStatus(update_engine::UpdateStatus::IDLE),
+          Return(true)));
   UmTestUtils::ExpectVariableHasValue(Stage::kIdle, provider_->var_stage());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetStageOkayCheckingForUpdate) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(
-              SetArgPointee<2>(update_engine::kUpdateStatusCheckingForUpdate),
-              Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusStatus(
+                          update_engine::UpdateStatus::CHECKING_FOR_UPDATE),
+                      Return(true)));
   UmTestUtils::ExpectVariableHasValue(Stage::kCheckingForUpdate,
                                       provider_->var_stage());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetStageOkayUpdateAvailable) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(
-              SetArgPointee<2>(update_engine::kUpdateStatusUpdateAvailable),
-              Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusStatus(
+                          update_engine::UpdateStatus::UPDATE_AVAILABLE),
+                      Return(true)));
   UmTestUtils::ExpectVariableHasValue(Stage::kUpdateAvailable,
                                       provider_->var_stage());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetStageOkayDownloading) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<2>(update_engine::kUpdateStatusDownloading),
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusStatus(
+                          update_engine::UpdateStatus::DOWNLOADING),
                       Return(true)));
   UmTestUtils::ExpectVariableHasValue(Stage::kDownloading,
                                       provider_->var_stage());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetStageOkayVerifying) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<2>(update_engine::kUpdateStatusVerifying),
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusStatus(
+                          update_engine::UpdateStatus::VERIFYING),
                       Return(true)));
   UmTestUtils::ExpectVariableHasValue(Stage::kVerifying,
                                       provider_->var_stage());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetStageOkayFinalizing) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<2>(update_engine::kUpdateStatusFinalizing),
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusStatus(
+                          update_engine::UpdateStatus::FINALIZING),
                       Return(true)));
   UmTestUtils::ExpectVariableHasValue(Stage::kFinalizing,
                                       provider_->var_stage());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetStageOkayUpdatedNeedReboot) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(
-              SetArgPointee<2>(update_engine::kUpdateStatusUpdatedNeedReboot),
-              Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusStatus(
+                          update_engine::UpdateStatus::UPDATED_NEED_REBOOT),
+                      Return(true)));
   UmTestUtils::ExpectVariableHasValue(Stage::kUpdatedNeedReboot,
                                       provider_->var_stage());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetStageOkayReportingErrorEvent) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(
-              SetArgPointee<2>(update_engine::kUpdateStatusReportingErrorEvent),
-              Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusStatus(
+                          update_engine::UpdateStatus::REPORTING_ERROR_EVENT),
+                      Return(true)));
   UmTestUtils::ExpectVariableHasValue(Stage::kReportingErrorEvent,
                                       provider_->var_stage());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetStageOkayAttemptingRollback) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(
-              SetArgPointee<2>(update_engine::kUpdateStatusAttemptingRollback),
-              Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusStatus(
+                          update_engine::UpdateStatus::ATTEMPTING_ROLLBACK),
+                      Return(true)));
   UmTestUtils::ExpectVariableHasValue(Stage::kAttemptingRollback,
                                       provider_->var_stage());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetStageFailNoValue) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
       .WillOnce(Return(false));
   UmTestUtils::ExpectVariableNotSet(provider_->var_stage());
 }
 
-TEST_F(UmRealUpdaterProviderTest, GetStageFailUnknown) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<2>("FooUpdateEngineState"),
-                      Return(true)));
-  UmTestUtils::ExpectVariableNotSet(provider_->var_stage());
-}
-
-TEST_F(UmRealUpdaterProviderTest, GetStageFailEmpty) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<2>(""), Return(true)));
-  UmTestUtils::ExpectVariableNotSet(provider_->var_stage());
-}
-
 TEST_F(UmRealUpdaterProviderTest, GetNewVersionOkay) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<3>("1.2.0"), Return(true)));
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(
+          DoAll(ActionSetUpdateEngineStatusNewVersion("1.2.0"), Return(true)));
   UmTestUtils::ExpectVariableHasValue(string("1.2.0"),
                                       provider_->var_new_version());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetNewVersionFailNoValue) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
       .WillOnce(Return(false));
   UmTestUtils::ExpectVariableNotSet(provider_->var_new_version());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetPayloadSizeOkayZero) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<4>(static_cast<int64_t>(0)), Return(true)));
-  UmTestUtils::ExpectVariableHasValue(static_cast<int64_t>(0),
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(
+          ActionSetUpdateEngineStatusNewSizeBytes(static_cast<uint64_t>(0)),
+          Return(true)));
+  UmTestUtils::ExpectVariableHasValue(static_cast<uint64_t>(0),
                                       provider_->var_payload_size());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetPayloadSizeOkayArbitrary) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<4>(static_cast<int64_t>(567890)),
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusNewSizeBytes(
+                          static_cast<uint64_t>(567890)),
                       Return(true)));
-  UmTestUtils::ExpectVariableHasValue(static_cast<int64_t>(567890),
+  UmTestUtils::ExpectVariableHasValue(static_cast<uint64_t>(567890),
                                       provider_->var_payload_size());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetPayloadSizeOkayTwoGigabytes) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<4>(static_cast<int64_t>(1) << 31),
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
+      .WillOnce(DoAll(ActionSetUpdateEngineStatusNewSizeBytes(
+                          static_cast<uint64_t>(1) << 31),
                       Return(true)));
-  UmTestUtils::ExpectVariableHasValue(static_cast<int64_t>(1) << 31,
+  UmTestUtils::ExpectVariableHasValue(static_cast<uint64_t>(1) << 31,
                                       provider_->var_payload_size());
 }
 
 TEST_F(UmRealUpdaterProviderTest, GetPayloadSizeFailNoValue) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(), GetStatus(_))
       .WillOnce(Return(false));
   UmTestUtils::ExpectVariableNotSet(provider_->var_payload_size());
 }
 
-TEST_F(UmRealUpdaterProviderTest, GetPayloadSizeFailNegative) {
-  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
-              GetStatus(_, _, _, _, _))
-      .WillOnce(DoAll(SetArgPointee<4>(static_cast<int64_t>(-1024)),
-                      Return(true)));
-  UmTestUtils::ExpectVariableNotSet(provider_->var_payload_size());
-}
-
 TEST_F(UmRealUpdaterProviderTest, GetCurrChannelOkay) {
   const string kChannelName("foo-channel");
   OmahaRequestParams request_params(&fake_sys_state_);
@@ -440,4 +430,20 @@
       kPollInterval, provider_->var_server_dictated_poll_interval());
 }
 
+TEST_F(UmRealUpdaterProviderTest, GetUpdateRestrictions) {
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
+              GetCurrentUpdateAttemptFlags())
+      .WillRepeatedly(Return(UpdateAttemptFlags::kFlagRestrictDownload |
+                             UpdateAttemptFlags::kFlagNonInteractive));
+  UmTestUtils::ExpectVariableHasValue(UpdateRestrictions::kRestrictDownloading,
+                                      provider_->var_update_restrictions());
+}
+
+TEST_F(UmRealUpdaterProviderTest, GetUpdateRestrictionsNone) {
+  EXPECT_CALL(*fake_sys_state_.mock_update_attempter(),
+              GetCurrentUpdateAttemptFlags())
+      .WillRepeatedly(Return(UpdateAttemptFlags::kNone));
+  UmTestUtils::ExpectVariableHasValue(UpdateRestrictions::kNone,
+                                      provider_->var_update_restrictions());
+}
 }  // namespace chromeos_update_manager
diff --git a/update_manager/state_factory.cc b/update_manager/state_factory.cc
index 70fc80b..208ed51 100644
--- a/update_manager/state_factory.cc
+++ b/update_manager/state_factory.cc
@@ -19,7 +19,6 @@
 #include <memory>
 
 #include <base/logging.h>
-#include <brillo/make_unique_ptr.h>
 #if USE_DBUS
 #include <session_manager/dbus-proxies.h>
 #endif  // USE_DBUS
@@ -57,8 +56,7 @@
       chromeos_update_engine::DBusConnection::Get()->GetDBus();
   unique_ptr<RealDevicePolicyProvider> device_policy_provider(
       new RealDevicePolicyProvider(
-          brillo::make_unique_ptr(
-              new org::chromium::SessionManagerInterfaceProxy(bus)),
+          std::make_unique<org::chromium::SessionManagerInterfaceProxy>(bus),
           policy_provider));
 #else
   unique_ptr<RealDevicePolicyProvider> device_policy_provider(
@@ -73,6 +71,7 @@
   unique_ptr<RealRandomProvider> random_provider(new RealRandomProvider());
   unique_ptr<RealSystemProvider> system_provider(new RealSystemProvider(
       system_state->hardware(), system_state->boot_control(), libcros_proxy));
+
   unique_ptr<RealTimeProvider> time_provider(new RealTimeProvider(clock));
   unique_ptr<RealUpdaterProvider> updater_provider(
       new RealUpdaterProvider(system_state));
diff --git a/update_manager/update_manager.cc b/update_manager/update_manager.cc
index 8e9b221..25f3216 100644
--- a/update_manager/update_manager.cc
+++ b/update_manager/update_manager.cc
@@ -16,7 +16,11 @@
 
 #include "update_engine/update_manager/update_manager.h"
 
+#ifdef __ANDROID__
+#include "update_engine/update_manager/android_things_policy.h"
+#else
 #include "update_engine/update_manager/chromeos_policy.h"
+#endif  // __ANDROID__
 #include "update_engine/update_manager/state.h"
 
 namespace chromeos_update_manager {
@@ -28,9 +32,11 @@
         evaluation_timeout_(evaluation_timeout),
         expiration_timeout_(expiration_timeout),
         weak_ptr_factory_(this) {
-  // TODO(deymo): Make it possible to replace this policy with a different
-  // implementation with a build-time flag.
+#ifdef __ANDROID__
+  policy_.reset(new AndroidThingsPolicy());
+#else
   policy_.reset(new ChromeOSPolicy());
+#endif  // __ANDROID__
 }
 
 UpdateManager::~UpdateManager() {
diff --git a/update_manager/update_manager_unittest.cc b/update_manager/update_manager_unittest.cc
index 03f1610..c2766ea 100644
--- a/update_manager/update_manager_unittest.cc
+++ b/update_manager/update_manager_unittest.cc
@@ -67,7 +67,9 @@
   now_exp.minute = 5;
   now_exp.second = 33;
   now_exp.millisecond = 675;
-  return Time::FromLocalExploded(now_exp);
+  Time time;
+  ignore_result(Time::FromLocalExploded(now_exp, &time));
+  return time;
 }
 
 }  // namespace
diff --git a/update_manager/updater_provider.h b/update_manager/updater_provider.h
index 8048d38..cb62623 100644
--- a/update_manager/updater_provider.h
+++ b/update_manager/updater_provider.h
@@ -44,6 +44,12 @@
   kPeriodic,
 };
 
+// These enum values are a bit-field.
+enum UpdateRestrictions : int {
+  kNone,
+  kRestrictDownloading = (1 << 0),
+};
+
 // Provider for Chrome OS update related information.
 class UpdaterProvider : public Provider {
  public:
@@ -79,7 +85,7 @@
 
   // A variable returning the update payload size. The payload size is
   // guaranteed to be non-negative.
-  virtual Variable<int64_t>* var_payload_size() = 0;
+  virtual Variable<uint64_t>* var_payload_size() = 0;
 
   // A variable returning the current channel.
   virtual Variable<std::string>* var_curr_channel() = 0;
@@ -105,6 +111,10 @@
   // scheduled update.
   virtual Variable<UpdateRequestStatus>* var_forced_update_requested() = 0;
 
+  // A variable that returns the update restriction flags that are set
+  // for all updates.
+  virtual Variable<UpdateRestrictions>* var_update_restrictions() = 0;
+
  protected:
   UpdaterProvider() {}
 
diff --git a/update_metadata.proto b/update_metadata.proto
index 596a04e..b5d6c59 100644
--- a/update_metadata.proto
+++ b/update_metadata.proto
@@ -77,10 +77,15 @@
 // - REPLACE_XZ: Replace the dst_extents with the contents of the attached
 //   xz file after decompression. The xz file should only use crc32 or no crc at
 //   all to be compatible with xz-embedded.
+// - PUFFDIFF: Read the data in src_extents in the old partition, perform
+//   puffpatch with the attached data and write the new data to dst_extents in
+//   the new partition.
 //
 // The operations allowed in the payload (supported by the client) depend on the
 // major and minor version. See InstallOperation.Type bellow for details.
 
+syntax = "proto2";
+
 package chromeos_update_engine;
 option optimize_for = LITE_RUNTIME;
 
@@ -159,12 +164,13 @@
 
     // On minor version 3 or newer and on major version 2 or newer, these
     // operations are supported:
-    ZERO = 6;  // Write zeros in the destination.
-    DISCARD = 7;  // Discard the destination blocks, reading as undefined.
     REPLACE_XZ = 8; // Replace destination extents w/ attached xz data.
 
     // On minor version 4 or newer, these operations are supported:
-    IMGDIFF = 9; // The data is in imgdiff format.
+    ZERO = 6;  // Write zeros in the destination.
+    DISCARD = 7;  // Discard the destination blocks, reading as undefined.
+    PUFFDIFF = 9;  // The data is in puffdiff format.
+    BROTLI_BSDIFF = 10;  // Like SOURCE_BSDIFF, but compressed with brotli.
   }
   required Type type = 1;
   // The offset into the delta file (after the protobuf)
@@ -176,14 +182,15 @@
   // Ordered list of extents that are read from (if any) and written to.
   repeated Extent src_extents = 4;
   // Byte length of src, equal to the number of blocks in src_extents *
-  // block_size. It is used for BSDIFF, because we need to pass that
-  // external program the number of bytes to read from the blocks we pass it.
-  // This is not used in any other operation.
+  // block_size. It is used for BSDIFF and SOURCE_BSDIFF, because we need to
+  // pass that external program the number of bytes to read from the blocks we
+  // pass it.  This is not used in any other operation.
   optional uint64 src_length = 5;
 
   repeated Extent dst_extents = 6;
   // Byte length of dst, equal to the number of blocks in dst_extents *
-  // block_size. Used for BSDIFF, but not in any other operation.
+  // block_size. Used for BSDIFF and SOURCE_BSDIFF, but not in any other
+  // operation.
   optional uint64 dst_length = 7;
 
   // Optional SHA 256 hash of the blob associated with this operation.
diff --git a/utils_android.cc b/utils_android.cc
index 38d62ea..393e65a 100644
--- a/utils_android.cc
+++ b/utils_android.cc
@@ -16,7 +16,6 @@
 
 #include "update_engine/utils_android.h"
 
-#include <cutils/properties.h>
 #include <fs_mgr.h>
 
 using std::string;