Implement WebBluetooth descriptor.readValue()

content/browser/bluetooth/web_bluetooth_service_impl.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // ID Not In Map Note: A service, characteristic, or descriptor ID not in the
 // corresponding WebBluetoothServiceImpl map [service_id_to_device_address_,
 // characteristic_id_to_service_id_, descriptor_id_to_characteristic_id_]
 // implies a hostile renderer because a renderer obtains the corresponding ID
 // from this class and it will be added to the map at that time.
 
@@ skipping 134 matching lines @@
       case CacheQueryOutcome::BAD_RENDERER:
         NOTREACHED();
         return blink::mojom::WebBluetoothResult::DEVICE_NO_LONGER_IN_RANGE;
       case CacheQueryOutcome::NO_DEVICE:
         return blink::mojom::WebBluetoothResult::DEVICE_NO_LONGER_IN_RANGE;
       case CacheQueryOutcome::NO_SERVICE:
         return blink::mojom::WebBluetoothResult::SERVICE_NO_LONGER_EXISTS;
       case CacheQueryOutcome::NO_CHARACTERISTIC:
         return blink::mojom::WebBluetoothResult::
             CHARACTERISTIC_NO_LONGER_EXISTS;
+      case CacheQueryOutcome::NO_DESCRIPTOR:
+        return blink::mojom::WebBluetoothResult::DESCRIPTOR_NO_LONGER_EXISTS;
     }
     NOTREACHED();
     return blink::mojom::WebBluetoothResult::DEVICE_NO_LONGER_IN_RANGE;
   }
 
   device::BluetoothDevice* device = nullptr;
   device::BluetoothRemoteGattService* service = nullptr;
   device::BluetoothRemoteGattCharacteristic* characteristic = nullptr;
+  device::BluetoothRemoteGattDescriptor* descriptor = nullptr;
   CacheQueryOutcome outcome;
 };
 
 WebBluetoothServiceImpl::WebBluetoothServiceImpl(
     RenderFrameHost* render_frame_host,
     blink::mojom::WebBluetoothServiceRequest request)
     : WebContentsObserver(WebContents::FromRenderFrameHost(render_frame_host)),
       connected_devices_(new FrameConnectedBluetoothDevices(render_frame_host)),
       render_frame_host_(render_frame_host),
       binding_(this, std::move(request)),
@@ skipping 557 matching lines @@
     // If the frame hasn't subscribed to notifications before we just
     // run the callback.
     callback.Run();
     return;
   }
   notify_session_iter->second->Stop(base::Bind(
       &WebBluetoothServiceImpl::OnStopNotifySessionComplete,
       weak_ptr_factory_.GetWeakPtr(), characteristic_instance_id, callback));
 }
 
+void WebBluetoothServiceImpl::RemoteDescriptorReadValue(
+    const std::string& descriptor_instance_id,
+    const RemoteDescriptorReadValueCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+
+  const CacheQueryResult query_result =
+      QueryCacheForDescriptor(descriptor_instance_id);
+
+  if (query_result.outcome == CacheQueryOutcome::BAD_RENDERER) {
+    return;
+  }
+
+  if (query_result.outcome != CacheQueryOutcome::SUCCESS) {
+    callback.Run(query_result.GetWebResult(), base::nullopt /* value */);
+    return;
+  }
+
+  if (BluetoothBlocklist::Get().IsExcludedFromReads(
+          query_result.descriptor->GetUUID())) {
+    callback.Run(blink::mojom::WebBluetoothResult::BLOCKLISTED_READ,
+                 base::nullopt /* value */);
+    return;
+  }
+
+  query_result.descriptor->ReadRemoteDescriptor(
+      base::Bind(&WebBluetoothServiceImpl::OnDescriptorReadValueSuccess,
+                 weak_ptr_factory_.GetWeakPtr(), callback),
+      base::Bind(&WebBluetoothServiceImpl::OnDescriptorReadValueFailed,
+                 weak_ptr_factory_.GetWeakPtr(), callback));
+}
+
 void WebBluetoothServiceImpl::RequestDeviceImpl(
     blink::mojom::WebBluetoothRequestDeviceOptionsPtr options,
     const RequestDeviceCallback& callback,
     device::BluetoothAdapter* adapter) {
   // requestDevice() can only be called when processing a user-gesture and any
   // user gesture outside of a chooser should close the chooser. This does
   // not happen on all platforms so we don't DCHECK that the old one is closed.
   // We destroy the old chooser before constructing the new one to make sure
   // they can't conflict.
   device_chooser_controller_.reset();
@@ skipping 181 matching lines @@
       error_code, UMAGATTOperation::START_NOTIFICATIONS));
 }
 
 void WebBluetoothServiceImpl::OnStopNotifySessionComplete(
     const std::string& characteristic_instance_id,
     const RemoteCharacteristicStopNotificationsCallback& callback) {
   characteristic_id_to_notify_session_.erase(characteristic_instance_id);
   callback.Run();
 }
 
+void WebBluetoothServiceImpl::OnDescriptorReadValueSuccess(
+    const RemoteDescriptorReadValueCallback& callback,
+    const std::vector<uint8_t>& value) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);

[ortuno, 2017/01/20 04:30:52]

Add todo for metrics.

[dougt, 2017/01/23 21:40:35]

Acknowledged.

There are probably a dozen places that I need to add metrics. I would rather not
add these TODOs in this CL and instead, just add them when I fix 667319.

+  callback.Run(blink::mojom::WebBluetoothResult::SUCCESS, value);
+}
+
+void WebBluetoothServiceImpl::OnDescriptorReadValueFailed(
+    const RemoteDescriptorReadValueCallback& callback,
+    device::BluetoothRemoteGattService::GattErrorCode error_code) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  // TODO(667319) We are reporting failures to UMA but not reporting successes.
+  callback.Run(TranslateGATTErrorAndRecord(error_code,
+                                           UMAGATTOperation::DESCRIPTOR_READ),
+               base::nullopt /* value */);
+}
+
 CacheQueryResult WebBluetoothServiceImpl::QueryCacheForDevice(
     const WebBluetoothDeviceId& device_id) {
   const std::string& device_address =
       allowed_devices_map_.GetDeviceAddress(GetOrigin(), device_id);
   if (device_address.empty()) {
     CrashRendererAndClosePipe(bad_message::BDH_DEVICE_NOT_ALLOWED_FOR_ORIGIN);
     return CacheQueryResult(CacheQueryOutcome::BAD_RENDERER);
   }
 
   CacheQueryResult result;
@@ skipping 62 matching lines @@
   result.characteristic =
       result.service->GetCharacteristic(characteristic_instance_id);
 
   if (result.characteristic == nullptr) {
     result.outcome = CacheQueryOutcome::NO_CHARACTERISTIC;
   }
 
   return result;
 }
 
+CacheQueryResult WebBluetoothServiceImpl::QueryCacheForDescriptor(
+    const std::string& descriptor_instance_id) {
+  auto descriptor_iter =
+      descriptor_id_to_characteristic_id_.find(descriptor_instance_id);
+
+  // Kill the render, see "ID Not in Map Note" above.
+  if (descriptor_iter == descriptor_id_to_characteristic_id_.end()) {
+    CrashRendererAndClosePipe(bad_message::BDH_INVALID_DESCRIPTOR_ID);
+    return CacheQueryResult(CacheQueryOutcome::BAD_RENDERER);
+  }
+
+  CacheQueryResult result =
+      QueryCacheForCharacteristic(descriptor_iter->second);
+
+  if (result.outcome != CacheQueryOutcome::SUCCESS) {
+    return result;
+  }
+
+  result.descriptor =
+      result.characteristic->GetDescriptor(descriptor_instance_id);
+
+  if (result.descriptor == nullptr) {
+    result.outcome = CacheQueryOutcome::NO_DESCRIPTOR;
+  }
+
+  return result;
+}
+
 RenderProcessHost* WebBluetoothServiceImpl::GetRenderProcessHost() {
   return render_frame_host_->GetProcess();
 }
 
 device::BluetoothAdapter* WebBluetoothServiceImpl::GetAdapter() {
   return BluetoothAdapterFactoryWrapper::Get().GetAdapter(this);
 }
 
 void WebBluetoothServiceImpl::CrashRendererAndClosePipe(
     bad_message::BadMessageReason reason) {
@@ skipping 12 matching lines @@
   characteristic_id_to_service_id_.clear();
   service_id_to_device_address_.clear();
   connected_devices_.reset(
       new FrameConnectedBluetoothDevices(render_frame_host_));
   allowed_devices_map_ = BluetoothAllowedDevicesMap();
   device_chooser_controller_.reset();
   BluetoothAdapterFactoryWrapper::Get().ReleaseAdapter(this);
 }
 
 }  // namespace content