| /* |
| * 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. |
| */ |
| |
| package com.android.bluetooth.pan; |
| |
| import android.bluetooth.BluetoothDevice; |
| import android.content.Context; |
| import android.net.ConnectivityManager; |
| import android.net.DhcpResults; |
| import android.net.LinkProperties; |
| import android.net.NetworkAgent; |
| import android.net.NetworkCapabilities; |
| import android.net.NetworkFactory; |
| import android.net.NetworkInfo; |
| import android.net.NetworkInfo.DetailedState; |
| import android.net.NetworkUtils; |
| import android.os.Looper; |
| import android.text.TextUtils; |
| import android.util.Slog; |
| |
| import com.android.bluetooth.pan.PanService; |
| import com.android.internal.util.AsyncChannel; |
| |
| /** |
| * This class tracks the data connection associated with Bluetooth |
| * reverse tethering. PanService calls it when a reverse tethered |
| * connection needs to be activated or deactivated. |
| * |
| * @hide |
| */ |
| public class BluetoothTetheringNetworkFactory extends NetworkFactory { |
| private static final String NETWORK_TYPE = "Bluetooth Tethering"; |
| private static final String TAG = "BluetoothTetheringNetworkFactory"; |
| private static final int NETWORK_SCORE = 69; |
| |
| private final NetworkCapabilities mNetworkCapabilities; |
| private final Context mContext; |
| private final PanService mPanService; |
| |
| // All accesses to these must be synchronized(this). |
| private final NetworkInfo mNetworkInfo; |
| private LinkProperties mLinkProperties; |
| private NetworkAgent mNetworkAgent; |
| |
| public BluetoothTetheringNetworkFactory(Context context, Looper looper, PanService panService) { |
| super(looper, context, NETWORK_TYPE, new NetworkCapabilities()); |
| |
| mContext = context; |
| mPanService = panService; |
| |
| mNetworkInfo = new NetworkInfo(ConnectivityManager.TYPE_BLUETOOTH, 0, NETWORK_TYPE, ""); |
| mLinkProperties = new LinkProperties(); |
| mNetworkCapabilities = new NetworkCapabilities(); |
| initNetworkCapabilities(); |
| setCapabilityFilter(mNetworkCapabilities); |
| } |
| |
| // Called by NetworkFactory when PanService and NetworkFactory both desire a Bluetooth |
| // reverse-tether connection. A network interface for Bluetooth reverse-tethering can be |
| // assumed to be available because we only register our NetworkFactory when it is so. |
| @Override |
| protected void startNetwork() { |
| // TODO: Handle DHCP renew. |
| Thread dhcpThread = new Thread(new Runnable() { |
| public void run() { |
| LinkProperties linkProperties; |
| synchronized (BluetoothTetheringNetworkFactory.this) { |
| linkProperties = mLinkProperties; |
| if (linkProperties.getInterfaceName() == null) { |
| Slog.e(TAG, "attempted to reverse tether without interface name"); |
| return; |
| } |
| log("dhcpThread(+" + linkProperties.getInterfaceName() + |
| "): mNetworkInfo=" + mNetworkInfo); |
| } |
| |
| DhcpResults dhcpResults = new DhcpResults(); |
| // TODO: Handle DHCP renewals better. |
| // In general runDhcp handles DHCP renewals for us, because |
| // the dhcp client stays running, but if the renewal fails, |
| // we will lose our IP address and connectivity without |
| // noticing. |
| if (!NetworkUtils.runDhcp(linkProperties.getInterfaceName(), dhcpResults)) { |
| Slog.e(TAG, "DHCP request error:" + NetworkUtils.getDhcpError()); |
| synchronized(BluetoothTetheringNetworkFactory.this) { |
| setScoreFilter(-1); |
| } |
| return; |
| } |
| |
| synchronized(BluetoothTetheringNetworkFactory.this) { |
| mLinkProperties = dhcpResults.toLinkProperties( |
| linkProperties.getInterfaceName()); |
| mNetworkInfo.setIsAvailable(true); |
| mNetworkInfo.setDetailedState(DetailedState.CONNECTED, null, null); |
| |
| // Create our NetworkAgent. |
| mNetworkAgent = new NetworkAgent(getLooper(), mContext, NETWORK_TYPE, |
| mNetworkInfo, mNetworkCapabilities, mLinkProperties, NETWORK_SCORE) { |
| public void unwanted() { |
| BluetoothTetheringNetworkFactory.this.onCancelRequest(); |
| }; |
| }; |
| } |
| } |
| }); |
| dhcpThread.start(); |
| } |
| |
| // Called from NetworkFactory to indicate ConnectivityService no longer desires a Bluetooth |
| // reverse-tether network. |
| @Override |
| protected void stopNetwork() { |
| // Let NetworkAgent disconnect do the teardown. |
| } |
| |
| // Called by the NetworkFactory, NetworkAgent or PanService to tear down network. |
| private synchronized void onCancelRequest() { |
| if (!TextUtils.isEmpty(mLinkProperties.getInterfaceName())) { |
| NetworkUtils.stopDhcp(mLinkProperties.getInterfaceName()); |
| } |
| mLinkProperties.clear(); |
| mNetworkInfo.setDetailedState(DetailedState.DISCONNECTED, null, null); |
| if (mNetworkAgent != null) { |
| mNetworkAgent.sendNetworkInfo(mNetworkInfo); |
| mNetworkAgent = null; |
| } |
| for (BluetoothDevice device : mPanService.getConnectedDevices()) { |
| mPanService.disconnect(device); |
| } |
| } |
| |
| // Called by PanService when a network interface for Bluetooth reverse-tethering |
| // becomes available. We register our NetworkFactory at this point. |
| public void startReverseTether(final String iface) { |
| if (iface == null || TextUtils.isEmpty(iface)) { |
| Slog.e(TAG, "attempted to reverse tether with empty interface"); |
| return; |
| } |
| synchronized(this) { |
| if (mLinkProperties.getInterfaceName() != null) { |
| Slog.e(TAG, "attempted to reverse tether while already in process"); |
| return; |
| } |
| mLinkProperties = new LinkProperties(); |
| mLinkProperties.setInterfaceName(iface); |
| // Advertise ourselves to ConnectivityService. |
| register(); |
| setScoreFilter(NETWORK_SCORE); |
| } |
| } |
| |
| // Called by PanService when a network interface for Bluetooth reverse-tethering |
| // goes away. We stop advertising ourselves to ConnectivityService at this point. |
| public synchronized void stopReverseTether() { |
| if (TextUtils.isEmpty(mLinkProperties.getInterfaceName())) { |
| Slog.e(TAG, "attempted to stop reverse tether with nothing tethered"); |
| return; |
| } |
| onCancelRequest(); |
| setScoreFilter(-1); |
| unregister(); |
| } |
| |
| private void initNetworkCapabilities() { |
| mNetworkCapabilities.addTransportType(NetworkCapabilities.TRANSPORT_BLUETOOTH); |
| mNetworkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET); |
| mNetworkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED); |
| // Bluetooth v3 and v4 go up to 24 Mbps. |
| // TODO: Adjust this to actual connection bandwidth. |
| mNetworkCapabilities.setLinkUpstreamBandwidthKbps(24 * 1000); |
| mNetworkCapabilities.setLinkDownstreamBandwidthKbps(24 * 1000); |
| } |
| } |