diff --git a/cros/dbus_service.cc b/cros/dbus_service.cc
new file mode 100644
index 0000000..d115195
--- /dev/null
+++ b/cros/dbus_service.cc
@@ -0,0 +1,223 @@
+//
+// Copyright (C) 2012 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/cros/dbus_service.h"
+
+#include <string>
+#include <vector>
+
+#include <update_engine/dbus-constants.h>
+
+#include "update_engine/cros/dbus_connection.h"
+#include "update_engine/proto_bindings/update_engine.pb.h"
+#include "update_engine/update_status_utils.h"
+
+namespace chromeos_update_engine {
+
+using brillo::ErrorPtr;
+using chromeos_update_engine::UpdateEngineService;
+using std::string;
+using std::vector;
+using update_engine::Operation;
+using update_engine::StatusResult;
+using update_engine::UpdateEngineStatus;
+
+namespace {
+// Converts the internal |UpdateEngineStatus| to the protobuf |StatusResult|.
+void ConvertToStatusResult(const UpdateEngineStatus& ue_status,
+                           StatusResult* out_status) {
+  out_status->set_last_checked_time(ue_status.last_checked_time);
+  out_status->set_progress(ue_status.progress);
+  out_status->set_current_operation(static_cast<Operation>(ue_status.status));
+  out_status->set_new_version(ue_status.new_version);
+  out_status->set_new_size(ue_status.new_size_bytes);
+  out_status->set_is_enterprise_rollback(ue_status.is_enterprise_rollback);
+  out_status->set_is_install(ue_status.is_install);
+  out_status->set_eol_date(ue_status.eol_date);
+  out_status->set_will_powerwash_after_reboot(
+      ue_status.will_powerwash_after_reboot);
+}
+}  // namespace
+
+DBusUpdateEngineService::DBusUpdateEngineService(SystemState* system_state)
+    : common_(new UpdateEngineService{system_state}) {}
+
+// org::chromium::UpdateEngineInterfaceInterface methods implementation.
+
+bool DBusUpdateEngineService::AttemptUpdate(ErrorPtr* error,
+                                            const string& in_app_version,
+                                            const string& in_omaha_url) {
+  return AttemptUpdateWithFlags(
+      error, in_app_version, in_omaha_url, 0 /* no flags */);
+}
+
+bool DBusUpdateEngineService::AttemptUpdateWithFlags(
+    ErrorPtr* error,
+    const string& in_app_version,
+    const string& in_omaha_url,
+    int32_t in_flags_as_int) {
+  update_engine::AttemptUpdateFlags flags =
+      static_cast<update_engine::AttemptUpdateFlags>(in_flags_as_int);
+  bool interactive = !(flags & update_engine::kAttemptUpdateFlagNonInteractive);
+  bool result;
+  return common_->AttemptUpdate(
+      error,
+      in_app_version,
+      in_omaha_url,
+      interactive ? 0 : update_engine::UpdateAttemptFlags::kFlagNonInteractive,
+      &result);
+}
+
+bool DBusUpdateEngineService::AttemptInstall(ErrorPtr* error,
+                                             const string& in_omaha_url,
+                                             const vector<string>& dlc_ids) {
+  return common_->AttemptInstall(error, in_omaha_url, dlc_ids);
+}
+
+bool DBusUpdateEngineService::AttemptRollback(ErrorPtr* error,
+                                              bool in_powerwash) {
+  return common_->AttemptRollback(error, in_powerwash);
+}
+
+bool DBusUpdateEngineService::CanRollback(ErrorPtr* error,
+                                          bool* out_can_rollback) {
+  return common_->CanRollback(error, out_can_rollback);
+}
+
+bool DBusUpdateEngineService::ResetStatus(ErrorPtr* error) {
+  return common_->ResetStatus(error);
+}
+
+bool DBusUpdateEngineService::SetDlcActiveValue(brillo::ErrorPtr* error,
+                                                bool is_active,
+                                                const string& dlc_id) {
+  return common_->SetDlcActiveValue(error, is_active, dlc_id);
+}
+
+bool DBusUpdateEngineService::GetStatusAdvanced(ErrorPtr* error,
+                                                StatusResult* out_status) {
+  UpdateEngineStatus status;
+  if (!common_->GetStatus(error, &status)) {
+    return false;
+  }
+
+  ConvertToStatusResult(status, out_status);
+  return true;
+}
+
+bool DBusUpdateEngineService::RebootIfNeeded(ErrorPtr* error) {
+  return common_->RebootIfNeeded(error);
+}
+
+bool DBusUpdateEngineService::SetChannel(ErrorPtr* error,
+                                         const string& in_target_channel,
+                                         bool in_is_powerwash_allowed) {
+  return common_->SetChannel(error, in_target_channel, in_is_powerwash_allowed);
+}
+
+bool DBusUpdateEngineService::GetChannel(ErrorPtr* error,
+                                         bool in_get_current_channel,
+                                         string* out_channel) {
+  return common_->GetChannel(error, in_get_current_channel, out_channel);
+}
+
+bool DBusUpdateEngineService::GetCohortHint(ErrorPtr* error,
+                                            string* out_cohort_hint) {
+  return common_->GetCohortHint(error, out_cohort_hint);
+}
+
+bool DBusUpdateEngineService::SetCohortHint(ErrorPtr* error,
+                                            const string& in_cohort_hint) {
+  return common_->SetCohortHint(error, in_cohort_hint);
+}
+
+bool DBusUpdateEngineService::SetP2PUpdatePermission(ErrorPtr* error,
+                                                     bool in_enabled) {
+  return common_->SetP2PUpdatePermission(error, in_enabled);
+}
+
+bool DBusUpdateEngineService::GetP2PUpdatePermission(ErrorPtr* error,
+                                                     bool* out_enabled) {
+  return common_->GetP2PUpdatePermission(error, out_enabled);
+}
+
+bool DBusUpdateEngineService::SetUpdateOverCellularPermission(ErrorPtr* error,
+                                                              bool in_allowed) {
+  return common_->SetUpdateOverCellularPermission(error, in_allowed);
+}
+
+bool DBusUpdateEngineService::SetUpdateOverCellularTarget(
+    brillo::ErrorPtr* error,
+    const std::string& target_version,
+    int64_t target_size) {
+  return common_->SetUpdateOverCellularTarget(
+      error, target_version, target_size);
+}
+
+bool DBusUpdateEngineService::GetUpdateOverCellularPermission(
+    ErrorPtr* error, bool* out_allowed) {
+  return common_->GetUpdateOverCellularPermission(error, out_allowed);
+}
+
+bool DBusUpdateEngineService::GetDurationSinceUpdate(
+    ErrorPtr* error, int64_t* out_usec_wallclock) {
+  return common_->GetDurationSinceUpdate(error, out_usec_wallclock);
+}
+
+bool DBusUpdateEngineService::GetPrevVersion(ErrorPtr* error,
+                                             string* out_prev_version) {
+  return common_->GetPrevVersion(error, out_prev_version);
+}
+
+bool DBusUpdateEngineService::GetRollbackPartition(
+    ErrorPtr* error, string* out_rollback_partition_name) {
+  return common_->GetRollbackPartition(error, out_rollback_partition_name);
+}
+
+bool DBusUpdateEngineService::GetLastAttemptError(
+    ErrorPtr* error, int32_t* out_last_attempt_error) {
+  return common_->GetLastAttemptError(error, out_last_attempt_error);
+}
+
+UpdateEngineAdaptor::UpdateEngineAdaptor(SystemState* system_state)
+    : org::chromium::UpdateEngineInterfaceAdaptor(&dbus_service_),
+      bus_(DBusConnection::Get()->GetDBus()),
+      dbus_service_(system_state),
+      dbus_object_(nullptr,
+                   bus_,
+                   dbus::ObjectPath(update_engine::kUpdateEngineServicePath)) {}
+
+void UpdateEngineAdaptor::RegisterAsync(
+    const base::Callback<void(bool)>& completion_callback) {
+  RegisterWithDBusObject(&dbus_object_);
+  dbus_object_.RegisterAsync(completion_callback);
+}
+
+bool UpdateEngineAdaptor::RequestOwnership() {
+  return bus_->RequestOwnershipAndBlock(update_engine::kUpdateEngineServiceName,
+                                        dbus::Bus::REQUIRE_PRIMARY);
+}
+
+void UpdateEngineAdaptor::SendStatusUpdate(
+    const UpdateEngineStatus& update_engine_status) {
+  StatusResult status;
+  ConvertToStatusResult(update_engine_status, &status);
+
+  // Send |StatusUpdateAdvanced| signal.
+  SendStatusUpdateAdvancedSignal(status);
+}
+
+}  // namespace chromeos_update_engine