| /* |
| * Copyright (C) 2019 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. |
| */ |
| |
| package com.android.car.connecteddevice.ble; |
| |
| import static com.android.car.connecteddevice.util.SafeLog.logd; |
| import static com.android.car.connecteddevice.util.SafeLog.loge; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.bluetooth.BluetoothAdapter; |
| import android.bluetooth.BluetoothDevice; |
| import android.bluetooth.BluetoothGattCharacteristic; |
| import android.bluetooth.BluetoothGattDescriptor; |
| import android.bluetooth.BluetoothGattService; |
| import android.bluetooth.le.AdvertiseCallback; |
| import android.bluetooth.le.AdvertiseData; |
| import android.bluetooth.le.AdvertiseSettings; |
| import android.car.encryptionrunner.EncryptionRunnerFactory; |
| import android.os.ParcelUuid; |
| |
| import com.android.car.connecteddevice.AssociationCallback; |
| import com.android.car.connecteddevice.model.AssociatedDevice; |
| import com.android.car.connecteddevice.storage.ConnectedDeviceStorage; |
| import com.android.car.connecteddevice.util.EventLog; |
| import com.android.internal.annotations.VisibleForTesting; |
| |
| import java.util.UUID; |
| import java.util.concurrent.Executors; |
| import java.util.concurrent.ScheduledExecutorService; |
| import java.util.concurrent.ScheduledFuture; |
| import java.util.concurrent.TimeUnit; |
| |
| /** |
| * Communication manager that allows for targeted connections to a specific device in the car. |
| */ |
| public class CarBlePeripheralManager extends CarBleManager { |
| |
| private static final String TAG = "CarBlePeripheralManager"; |
| |
| // Attribute protocol bytes attached to message. Available write size is MTU size minus att |
| // bytes. |
| private static final int ATT_PROTOCOL_BYTES = 3; |
| |
| // Arbitrary delay time for a retry of association advertising if bluetooth adapter name change |
| // fails. |
| private static final long ASSOCIATE_ADVERTISING_DELAY_MS = 10L; |
| |
| private static final UUID CLIENT_CHARACTERISTIC_CONFIG = |
| UUID.fromString("00002902-0000-1000-8000-00805f9b34fb"); |
| |
| private final BluetoothGattDescriptor mDescriptor = |
| new BluetoothGattDescriptor(CLIENT_CHARACTERISTIC_CONFIG, |
| BluetoothGattDescriptor.PERMISSION_READ |
| | BluetoothGattDescriptor.PERMISSION_WRITE); |
| |
| private final ScheduledExecutorService mScheduler = |
| Executors.newSingleThreadScheduledExecutor(); |
| |
| private final BlePeripheralManager mBlePeripheralManager; |
| |
| private final UUID mAssociationServiceUuid; |
| |
| private final BluetoothGattCharacteristic mWriteCharacteristic; |
| |
| private final BluetoothGattCharacteristic mReadCharacteristic; |
| |
| // BLE default is 23, minus 3 bytes for ATT_PROTOCOL. |
| private int mWriteSize = 20; |
| |
| private String mOriginalBluetoothName; |
| |
| private String mClientDeviceName; |
| |
| private String mClientDeviceAddress; |
| |
| private AssociationCallback mAssociationCallback; |
| |
| private AdvertiseCallback mAdvertiseCallback; |
| |
| /** |
| * Initialize a new instance of manager. |
| * |
| * @param blePeripheralManager {@link BlePeripheralManager} for establishing connection. |
| * @param connectedDeviceStorage Shared {@link ConnectedDeviceStorage} for companion features. |
| * @param associationServiceUuid {@link UUID} of association service. |
| * @param writeCharacteristicUuid {@link UUID} of characteristic the car will write to. |
| * @param readCharacteristicUuid {@link UUID} of characteristic the device will write to. |
| */ |
| public CarBlePeripheralManager(@NonNull BlePeripheralManager blePeripheralManager, |
| @NonNull ConnectedDeviceStorage connectedDeviceStorage, |
| @NonNull UUID associationServiceUuid, @NonNull UUID writeCharacteristicUuid, |
| @NonNull UUID readCharacteristicUuid) { |
| super(connectedDeviceStorage); |
| mBlePeripheralManager = blePeripheralManager; |
| mAssociationServiceUuid = associationServiceUuid; |
| mDescriptor.setValue(BluetoothGattDescriptor.ENABLE_INDICATION_VALUE); |
| mWriteCharacteristic = new BluetoothGattCharacteristic(writeCharacteristicUuid, |
| BluetoothGattCharacteristic.PROPERTY_NOTIFY, |
| BluetoothGattCharacteristic.PROPERTY_READ); |
| mReadCharacteristic = new BluetoothGattCharacteristic(readCharacteristicUuid, |
| BluetoothGattCharacteristic.PROPERTY_WRITE |
| | BluetoothGattCharacteristic.PROPERTY_WRITE_NO_RESPONSE, |
| BluetoothGattCharacteristic.PERMISSION_WRITE); |
| mReadCharacteristic.addDescriptor(mDescriptor); |
| } |
| |
| @Override |
| public void stop() { |
| super.stop(); |
| reset(); |
| } |
| |
| @Override |
| public void disconnectDevice(@NonNull String deviceId) { |
| BleDevice connectedDevice = getConnectedDevice(); |
| if (connectedDevice == null || !deviceId.equals(connectedDevice.mDeviceId)) { |
| return; |
| } |
| reset(); |
| } |
| |
| private void reset() { |
| resetBluetoothAdapterName(); |
| mClientDeviceAddress = null; |
| mClientDeviceName = null; |
| mAssociationCallback = null; |
| mBlePeripheralManager.cleanup(); |
| mConnectedDevices.clear(); |
| } |
| |
| /** Connect to device with provided id. */ |
| public void connectToDevice(@NonNull UUID deviceId) { |
| for (BleDevice device : mConnectedDevices) { |
| if (UUID.fromString(device.mDeviceId).equals(deviceId)) { |
| logd(TAG, "Already connected to device " + deviceId + "."); |
| // Already connected to this device. Ignore requests to connect again. |
| return; |
| } |
| } |
| |
| // Clear any previous session before starting a new one. |
| reset(); |
| |
| mAdvertiseCallback = new AdvertiseCallback() { |
| @Override |
| public void onStartSuccess(AdvertiseSettings settingsInEffect) { |
| super.onStartSuccess(settingsInEffect); |
| logd(TAG, "Successfully started advertising for device " + deviceId + "."); |
| } |
| }; |
| mBlePeripheralManager.unregisterCallback(mAssociationPeripheralCallback); |
| mBlePeripheralManager.registerCallback(mReconnectPeripheralCallback); |
| startAdvertising(deviceId, mAdvertiseCallback, /* includeDeviceName = */ false); |
| } |
| |
| @Nullable |
| private BleDevice getConnectedDevice() { |
| if (mConnectedDevices.isEmpty()) { |
| return null; |
| } |
| return mConnectedDevices.iterator().next(); |
| } |
| |
| /** Start the association with a new device */ |
| public void startAssociation(@NonNull String nameForAssociation, |
| @NonNull AssociationCallback callback) { |
| BluetoothAdapter adapter = BluetoothAdapter.getDefaultAdapter(); |
| if (adapter == null) { |
| loge(TAG, "Bluetooth is unavailable on this device. Unable to start associating."); |
| return; |
| } |
| |
| reset(); |
| mAssociationCallback = callback; |
| if (mOriginalBluetoothName == null) { |
| mOriginalBluetoothName = adapter.getName(); |
| } |
| adapter.setName(nameForAssociation); |
| logd(TAG, "Changing bluetooth adapter name from " + mOriginalBluetoothName + " to " |
| + nameForAssociation + "."); |
| mBlePeripheralManager.unregisterCallback(mReconnectPeripheralCallback); |
| mBlePeripheralManager.registerCallback(mAssociationPeripheralCallback); |
| mAdvertiseCallback = new AdvertiseCallback() { |
| @Override |
| public void onStartSuccess(AdvertiseSettings settingsInEffect) { |
| super.onStartSuccess(settingsInEffect); |
| callback.onAssociationStartSuccess(nameForAssociation); |
| logd(TAG, "Successfully started advertising for association."); |
| } |
| |
| @Override |
| public void onStartFailure(int errorCode) { |
| super.onStartFailure(errorCode); |
| callback.onAssociationStartFailure(); |
| logd(TAG, "Failed to start advertising for association. Error code: " + errorCode); |
| } |
| }; |
| attemptAssociationAdvertising(nameForAssociation, callback); |
| } |
| |
| /** Stop the association with any device. */ |
| public void stopAssociation(@NonNull AssociationCallback callback) { |
| if (!isAssociating() || callback != mAssociationCallback) { |
| return; |
| } |
| reset(); |
| } |
| |
| private void attemptAssociationAdvertising(@NonNull String adapterName, |
| @NonNull AssociationCallback callback) { |
| if (mOriginalBluetoothName != null |
| && adapterName.equals(BluetoothAdapter.getDefaultAdapter().getName())) { |
| startAdvertising(mAssociationServiceUuid, mAdvertiseCallback, |
| /* includeDeviceName = */ true); |
| return; |
| } |
| |
| ScheduledFuture future = mScheduler.schedule( |
| () -> attemptAssociationAdvertising(adapterName, callback), |
| ASSOCIATE_ADVERTISING_DELAY_MS, TimeUnit.MILLISECONDS); |
| if (future.isCancelled()) { |
| // Association failed to start. |
| callback.onAssociationStartFailure(); |
| return; |
| } |
| logd(TAG, "Adapter name change has not taken affect prior to advertising attempt. Trying " |
| + "again in " + ASSOCIATE_ADVERTISING_DELAY_MS + " milliseconds."); |
| } |
| |
| private void startAdvertising(@NonNull UUID serviceUuid, @NonNull AdvertiseCallback callback, |
| boolean includeDeviceName) { |
| BluetoothGattService gattService = new BluetoothGattService(serviceUuid, |
| BluetoothGattService.SERVICE_TYPE_PRIMARY); |
| gattService.addCharacteristic(mWriteCharacteristic); |
| gattService.addCharacteristic(mReadCharacteristic); |
| |
| AdvertiseData advertiseData = new AdvertiseData.Builder() |
| .setIncludeDeviceName(includeDeviceName) |
| .addServiceUuid(new ParcelUuid(serviceUuid)) |
| .build(); |
| mBlePeripheralManager.startAdvertising(gattService, advertiseData, callback); |
| } |
| |
| /** Notify that the user has accepted a pairing code or other out-of-band confirmation. */ |
| public void notifyOutOfBandAccepted() { |
| if (getConnectedDevice() == null) { |
| disconnectWithError("Null connected device found when out-of-band confirmation " |
| + "received."); |
| return; |
| } |
| |
| SecureBleChannel secureChannel = getConnectedDevice().mSecureChannel; |
| if (secureChannel == null) { |
| disconnectWithError("Null SecureBleChannel found for the current connected device " |
| + "when out-of-band confirmation received."); |
| return; |
| } |
| |
| secureChannel.notifyOutOfBandAccepted(); |
| } |
| |
| @VisibleForTesting |
| @Nullable |
| SecureBleChannel getConnectedDeviceChannel() { |
| BleDevice connectedDevice = getConnectedDevice(); |
| if (connectedDevice == null) { |
| return null; |
| } |
| |
| return connectedDevice.mSecureChannel; |
| } |
| |
| private void setDeviceId(@NonNull String deviceId) { |
| logd(TAG, "Setting device id: " + deviceId); |
| BleDevice connectedDevice = getConnectedDevice(); |
| if (connectedDevice == null) { |
| disconnectWithError("Null connected device found when device id received."); |
| return; |
| } |
| |
| connectedDevice.mDeviceId = deviceId; |
| mCallbacks.invoke(callback -> callback.onDeviceConnected(deviceId)); |
| } |
| |
| private void disconnectWithError(@NonNull String errorMessage) { |
| loge(TAG, errorMessage); |
| reset(); |
| } |
| |
| private void resetBluetoothAdapterName() { |
| if (mOriginalBluetoothName == null) { |
| return; |
| } |
| logd(TAG, "Changing bluetooth adapter name back to " + mOriginalBluetoothName + "."); |
| BluetoothAdapter.getDefaultAdapter().setName(mOriginalBluetoothName); |
| mOriginalBluetoothName = null; |
| } |
| |
| private void addConnectedDevice(BluetoothDevice device, boolean isReconnect) { |
| EventLog.onDeviceConnected(); |
| mBlePeripheralManager.stopAdvertising(mAdvertiseCallback); |
| mClientDeviceAddress = device.getAddress(); |
| mClientDeviceName = device.getName(); |
| if (mClientDeviceName == null) { |
| logd(TAG, "Device connected, but name is null; issuing request to retrieve device " |
| + "name."); |
| mBlePeripheralManager.retrieveDeviceName(device); |
| } |
| |
| BleDeviceMessageStream secureStream = new BleDeviceMessageStream(mBlePeripheralManager, |
| device, mWriteCharacteristic, mReadCharacteristic); |
| secureStream.setMaxWriteSize(mWriteSize); |
| SecureBleChannel secureChannel = new SecureBleChannel(secureStream, mStorage, isReconnect, |
| EncryptionRunnerFactory.newRunner()); |
| secureChannel.registerCallback(mSecureChannelCallback); |
| BleDevice bleDevice = new BleDevice(device, /* gatt = */ null); |
| bleDevice.mSecureChannel = secureChannel; |
| addConnectedDevice(bleDevice); |
| } |
| |
| private void setMtuSize(int mtuSize) { |
| mWriteSize = mtuSize - ATT_PROTOCOL_BYTES; |
| BleDevice connectedDevice = getConnectedDevice(); |
| if (connectedDevice != null |
| && connectedDevice.mSecureChannel != null |
| && connectedDevice.mSecureChannel.getStream() != null) { |
| connectedDevice.mSecureChannel.getStream().setMaxWriteSize(mWriteSize); |
| } |
| } |
| |
| private boolean isAssociating() { |
| return mAssociationCallback != null; |
| } |
| |
| private final BlePeripheralManager.Callback mReconnectPeripheralCallback = |
| new BlePeripheralManager.Callback() { |
| |
| @Override |
| public void onDeviceNameRetrieved(String deviceName) { |
| // Ignored. |
| } |
| |
| @Override |
| public void onMtuSizeChanged(int size) { |
| setMtuSize(size); |
| } |
| |
| @Override |
| public void onRemoteDeviceConnected(BluetoothDevice device) { |
| addConnectedDevice(device, /* isReconnect= */ true); |
| } |
| |
| @Override |
| public void onRemoteDeviceDisconnected(BluetoothDevice device) { |
| String deviceId = null; |
| BleDevice connectedDevice = getConnectedDevice(device); |
| // Reset before invoking callbacks to avoid a race condition with reconnect |
| // logic. |
| reset(); |
| if (connectedDevice != null) { |
| deviceId = connectedDevice.mDeviceId; |
| } |
| final String finalDeviceId = deviceId; |
| if (finalDeviceId != null) { |
| logd(TAG, "Connected device " + finalDeviceId + " disconnected."); |
| mCallbacks.invoke(callback -> callback.onDeviceDisconnected(finalDeviceId)); |
| } |
| } |
| }; |
| |
| private final BlePeripheralManager.Callback mAssociationPeripheralCallback = |
| new BlePeripheralManager.Callback() { |
| @Override |
| public void onDeviceNameRetrieved(String deviceName) { |
| if (deviceName == null) { |
| return; |
| } |
| mClientDeviceName = deviceName; |
| BleDevice connectedDevice = getConnectedDevice(); |
| if (connectedDevice == null || connectedDevice.mDeviceId == null) { |
| return; |
| } |
| mStorage.updateAssociatedDeviceName(connectedDevice.mDeviceId, deviceName); |
| } |
| |
| @Override |
| public void onMtuSizeChanged(int size) { |
| setMtuSize(size); |
| } |
| |
| @Override |
| public void onRemoteDeviceConnected(BluetoothDevice device) { |
| resetBluetoothAdapterName(); |
| addConnectedDevice(device, /* isReconnect = */ false); |
| BleDevice connectedDevice = getConnectedDevice(); |
| if (connectedDevice == null || connectedDevice.mSecureChannel == null) { |
| return; |
| } |
| connectedDevice.mSecureChannel.setShowVerificationCodeListener( |
| code -> { |
| if (!isAssociating()) { |
| loge(TAG, "No valid callback for association."); |
| return; |
| } |
| mAssociationCallback.onVerificationCodeAvailable(code); |
| }); |
| } |
| |
| @Override |
| public void onRemoteDeviceDisconnected(BluetoothDevice device) { |
| BleDevice connectedDevice = getConnectedDevice(device); |
| // Reset before invoking callbacks to avoid a race condition with reconnect |
| // logic. |
| reset(); |
| if (connectedDevice != null && connectedDevice.mDeviceId != null) { |
| mCallbacks.invoke(callback -> callback.onDeviceDisconnected( |
| connectedDevice.mDeviceId)); |
| } |
| } |
| }; |
| |
| private final SecureBleChannel.Callback mSecureChannelCallback = |
| new SecureBleChannel.Callback() { |
| @Override |
| public void onSecureChannelEstablished() { |
| BleDevice connectedDevice = getConnectedDevice(); |
| if (connectedDevice == null || connectedDevice.mDeviceId == null) { |
| disconnectWithError("Null device id found when secure channel " |
| + "established."); |
| return; |
| } |
| String deviceId = connectedDevice.mDeviceId; |
| if (mClientDeviceAddress == null) { |
| disconnectWithError("Null device address found when secure channel " |
| + "established."); |
| return; |
| } |
| if (isAssociating()) { |
| logd(TAG, "Secure channel established for un-associated device. Saving " |
| + "association of that device for current user."); |
| mStorage.addAssociatedDeviceForActiveUser( |
| new AssociatedDevice(deviceId, mClientDeviceAddress, |
| mClientDeviceName)); |
| if (mAssociationCallback != null) { |
| mAssociationCallback.onAssociationCompleted(deviceId); |
| mAssociationCallback = null; |
| } |
| } |
| mCallbacks.invoke(callback -> callback.onSecureChannelEstablished(deviceId)); |
| } |
| |
| @Override |
| public void onEstablishSecureChannelFailure(int error) { |
| BleDevice connectedDevice = getConnectedDevice(); |
| if (connectedDevice == null || connectedDevice.mDeviceId == null) { |
| disconnectWithError("Null device id found when secure channel failed to " |
| + "establish."); |
| return; |
| } |
| String deviceId = connectedDevice.mDeviceId; |
| mCallbacks.invoke(callback -> callback.onSecureChannelError(deviceId)); |
| |
| if (isAssociating()) { |
| mAssociationCallback.onAssociationError(error); |
| disconnectWithError("Error while establishing secure connection."); |
| } |
| } |
| |
| @Override |
| public void onMessageReceived(DeviceMessage deviceMessage) { |
| BleDevice connectedDevice = getConnectedDevice(); |
| if (connectedDevice == null || connectedDevice.mDeviceId == null) { |
| disconnectWithError("Null device id found when message received."); |
| return; |
| } |
| |
| logd(TAG, "Received new message from " + connectedDevice.mDeviceId |
| + " with " + deviceMessage.getMessage().length + " in its payload. " |
| + "Notifying " + mCallbacks.size() + " callbacks."); |
| mCallbacks.invoke( |
| callback ->callback.onMessageReceived(connectedDevice.mDeviceId, |
| deviceMessage)); |
| } |
| |
| @Override |
| public void onMessageReceivedError(Exception exception) { |
| // TODO(b/143879960) Extend the message error from here to continue up the |
| // chain. |
| } |
| |
| @Override |
| public void onDeviceIdReceived(String deviceId) { |
| setDeviceId(deviceId); |
| } |
| }; |
| } |