| /* |
| * 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. |
| */ |
| |
| package com.android.nfc.handover; |
| |
| import java.nio.BufferUnderflowException; |
| import java.nio.ByteBuffer; |
| import java.nio.charset.Charset; |
| import java.util.Arrays; |
| import java.util.HashMap; |
| import java.util.Random; |
| |
| import android.bluetooth.BluetoothAdapter; |
| import android.bluetooth.BluetoothDevice; |
| import android.content.BroadcastReceiver; |
| import android.content.ComponentName; |
| import android.content.Context; |
| import android.content.Intent; |
| import android.content.IntentFilter; |
| import android.content.ServiceConnection; |
| import android.net.Uri; |
| import android.nfc.FormatException; |
| import android.nfc.NdefMessage; |
| import android.nfc.NdefRecord; |
| import android.os.Bundle; |
| import android.os.Handler; |
| import android.os.IBinder; |
| import android.os.Message; |
| import android.os.Messenger; |
| import android.os.RemoteException; |
| import android.os.UserHandle; |
| import android.util.Log; |
| |
| /** |
| * Manages handover of NFC to other technologies. |
| */ |
| public class HandoverManager { |
| static final String TAG = "NfcHandover"; |
| static final boolean DBG = true; |
| |
| static final String ACTION_WHITELIST_DEVICE = |
| "android.btopp.intent.action.WHITELIST_DEVICE"; |
| |
| static final byte[] TYPE_NOKIA = "nokia.com:bt".getBytes(Charset.forName("US_ASCII")); |
| static final byte[] TYPE_BT_OOB = "application/vnd.bluetooth.ep.oob". |
| getBytes(Charset.forName("US_ASCII")); |
| |
| static final byte[] RTD_COLLISION_RESOLUTION = {0x63, 0x72}; // "cr"; |
| |
| static final int CARRIER_POWER_STATE_INACTIVE = 0; |
| static final int CARRIER_POWER_STATE_ACTIVE = 1; |
| static final int CARRIER_POWER_STATE_ACTIVATING = 2; |
| static final int CARRIER_POWER_STATE_UNKNOWN = 3; |
| |
| static final int MSG_HANDOVER_COMPLETE = 0; |
| static final int MSG_HEADSET_CONNECTED = 1; |
| static final int MSG_HEADSET_NOT_CONNECTED = 2; |
| |
| final Context mContext; |
| final BluetoothAdapter mBluetoothAdapter; |
| final Messenger mMessenger = new Messenger (new MessageHandler()); |
| |
| final Object mLock = new Object(); |
| // Variables below synchronized on mLock |
| HashMap<Integer, PendingHandoverTransfer> mPendingTransfers; |
| boolean mBluetoothHeadsetConnected; |
| int mHandoverTransferId; |
| Messenger mService = null; |
| boolean mBound; |
| String mLocalBluetoothAddress; |
| |
| static class BluetoothHandoverData { |
| public boolean valid = false; |
| public BluetoothDevice device; |
| public String name; |
| public boolean carrierActivating = false; |
| } |
| |
| class MessageHandler extends Handler { |
| @Override |
| public void handleMessage(Message msg) { |
| synchronized (mLock) { |
| switch (msg.what) { |
| case MSG_HANDOVER_COMPLETE: |
| int transferId = msg.arg1; |
| Log.d(TAG, "Completed transfer id: " + Integer.toString(transferId)); |
| if (mPendingTransfers.containsKey(transferId)) { |
| mPendingTransfers.remove(transferId); |
| } else { |
| Log.e(TAG, "Could not find completed transfer id: " + Integer.toString(transferId)); |
| } |
| break; |
| case MSG_HEADSET_CONNECTED: |
| mBluetoothHeadsetConnected = true; |
| break; |
| case MSG_HEADSET_NOT_CONNECTED: |
| mBluetoothHeadsetConnected = false; |
| break; |
| default: |
| break; |
| } |
| } |
| } |
| }; |
| |
| private ServiceConnection mConnection = new ServiceConnection() { |
| @Override |
| public void onServiceConnected(ComponentName name, IBinder service) { |
| synchronized (mLock) { |
| mService = new Messenger(service); |
| mBound = true; |
| // Register this client |
| Message msg = Message.obtain(null, HandoverService.MSG_REGISTER_CLIENT); |
| msg.replyTo = mMessenger; |
| try { |
| mService.send(msg); |
| } catch (RemoteException e) { |
| Log.e(TAG, "Failed to register client"); |
| } |
| } |
| } |
| |
| @Override |
| public void onServiceDisconnected(ComponentName name) { |
| synchronized (mLock) { |
| if (mBound) { |
| try { |
| Message msg = Message.obtain(null, HandoverService.MSG_DEREGISTER_CLIENT); |
| msg.replyTo = mMessenger; |
| mService.send(msg); |
| } catch (RemoteException e) { |
| // Service may have crashed - ignore |
| } |
| } |
| mService = null; |
| mBound = false; |
| } |
| } |
| }; |
| |
| public HandoverManager(Context context) { |
| mContext = context; |
| mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter(); |
| |
| mPendingTransfers = new HashMap<Integer, PendingHandoverTransfer>(); |
| |
| IntentFilter filter = new IntentFilter(Intent.ACTION_USER_SWITCHED); |
| mContext.registerReceiver(mReceiver, filter, null, null); |
| |
| mContext.bindService(new Intent(mContext, HandoverService.class), mConnection, |
| Context.BIND_AUTO_CREATE, UserHandle.USER_CURRENT); |
| } |
| |
| final BroadcastReceiver mReceiver = new BroadcastReceiver() { |
| @Override |
| public void onReceive(Context context, Intent intent) { |
| String action = intent.getAction(); |
| if (action.equals(Intent.ACTION_USER_SWITCHED)) { |
| // Re-bind a service for the current user |
| mContext.unbindService(mConnection); |
| mContext.bindService(new Intent(mContext, HandoverService.class), mConnection, |
| Context.BIND_AUTO_CREATE, UserHandle.USER_CURRENT); |
| } |
| } |
| }; |
| |
| static NdefRecord createCollisionRecord() { |
| byte[] random = new byte[2]; |
| new Random().nextBytes(random); |
| return new NdefRecord(NdefRecord.TNF_WELL_KNOWN, RTD_COLLISION_RESOLUTION, null, random); |
| } |
| |
| NdefRecord createBluetoothAlternateCarrierRecord(boolean activating) { |
| byte[] payload = new byte[4]; |
| payload[0] = (byte) (activating ? CARRIER_POWER_STATE_ACTIVATING : |
| CARRIER_POWER_STATE_ACTIVE); // Carrier Power State: Activating or active |
| payload[1] = 1; // length of carrier data reference |
| payload[2] = 'b'; // carrier data reference: ID for Bluetooth OOB data record |
| payload[3] = 0; // Auxiliary data reference count |
| return new NdefRecord(NdefRecord.TNF_WELL_KNOWN, NdefRecord.RTD_ALTERNATIVE_CARRIER, null, payload); |
| } |
| |
| NdefRecord createBluetoothOobDataRecord() { |
| byte[] payload = new byte[8]; |
| // Note: this field should be little-endian per the BTSSP spec |
| // The Android 4.1 implementation used big-endian order here. |
| // No single Android implementation has ever interpreted this |
| // length field when parsing this record though. |
| payload[0] = (byte) (payload.length & 0xFF); |
| payload[1] = (byte) ((payload.length >> 8) & 0xFF); |
| |
| synchronized (mLock) { |
| if (mLocalBluetoothAddress == null) { |
| mLocalBluetoothAddress = mBluetoothAdapter.getAddress(); |
| } |
| |
| byte[] addressBytes = addressToReverseBytes(mLocalBluetoothAddress); |
| System.arraycopy(addressBytes, 0, payload, 2, 6); |
| } |
| |
| return new NdefRecord(NdefRecord.TNF_MIME_MEDIA, TYPE_BT_OOB, new byte[]{'b'}, payload); |
| } |
| |
| public boolean isHandoverSupported() { |
| return (mBluetoothAdapter != null); |
| } |
| |
| public NdefMessage createHandoverRequestMessage() { |
| if (mBluetoothAdapter == null) return null; |
| |
| return new NdefMessage(createHandoverRequestRecord(), createBluetoothOobDataRecord()); |
| } |
| |
| NdefMessage createHandoverSelectMessage(boolean activating) { |
| return new NdefMessage(createHandoverSelectRecord(activating), createBluetoothOobDataRecord()); |
| } |
| |
| NdefRecord createHandoverSelectRecord(boolean activating) { |
| NdefMessage nestedMessage = new NdefMessage(createBluetoothAlternateCarrierRecord(activating)); |
| byte[] nestedPayload = nestedMessage.toByteArray(); |
| |
| ByteBuffer payload = ByteBuffer.allocate(nestedPayload.length + 1); |
| payload.put((byte)0x12); // connection handover v1.2 |
| payload.put(nestedPayload); |
| |
| byte[] payloadBytes = new byte[payload.position()]; |
| payload.position(0); |
| payload.get(payloadBytes); |
| return new NdefRecord(NdefRecord.TNF_WELL_KNOWN, NdefRecord.RTD_HANDOVER_SELECT, null, |
| payloadBytes); |
| } |
| |
| NdefRecord createHandoverRequestRecord() { |
| NdefMessage nestedMessage = new NdefMessage(createCollisionRecord(), |
| createBluetoothAlternateCarrierRecord(false)); |
| byte[] nestedPayload = nestedMessage.toByteArray(); |
| |
| ByteBuffer payload = ByteBuffer.allocate(nestedPayload.length + 1); |
| payload.put((byte)0x12); // connection handover v1.2 |
| payload.put(nestedMessage.toByteArray()); |
| |
| byte[] payloadBytes = new byte[payload.position()]; |
| payload.position(0); |
| payload.get(payloadBytes); |
| return new NdefRecord(NdefRecord.TNF_WELL_KNOWN, NdefRecord.RTD_HANDOVER_REQUEST, null, |
| payloadBytes); |
| } |
| |
| /** |
| * Return null if message is not a Handover Request, |
| * return the Handover Select response if it is. |
| */ |
| public NdefMessage tryHandoverRequest(NdefMessage m) { |
| if (m == null) return null; |
| if (mBluetoothAdapter == null) return null; |
| |
| if (DBG) Log.d(TAG, "tryHandoverRequest():" + m.toString()); |
| |
| NdefRecord r = m.getRecords()[0]; |
| if (r.getTnf() != NdefRecord.TNF_WELL_KNOWN) return null; |
| if (!Arrays.equals(r.getType(), NdefRecord.RTD_HANDOVER_REQUEST)) return null; |
| |
| // we have a handover request, look for BT OOB record |
| BluetoothHandoverData bluetoothData = null; |
| for (NdefRecord oob : m.getRecords()) { |
| if (oob.getTnf() == NdefRecord.TNF_MIME_MEDIA && |
| Arrays.equals(oob.getType(), TYPE_BT_OOB)) { |
| bluetoothData = parseBtOob(ByteBuffer.wrap(oob.getPayload())); |
| break; |
| } |
| } |
| if (bluetoothData == null) return null; |
| |
| // Note: there could be a race where we conclude |
| // that Bluetooth is already enabled, and shortly |
| // after the user turns it off. That will cause |
| // the transfer to fail, but there's nothing |
| // much we can do about it anyway. It shouldn't |
| // be common for the user to be changing BT settings |
| // while waiting to receive a picture. |
| boolean bluetoothActivating = !mBluetoothAdapter.isEnabled(); |
| synchronized (mLock) { |
| if (!mBound) { |
| Log.e(TAG, "Could not connect to handover service"); |
| return null; |
| } |
| Message msg = Message.obtain(null, HandoverService.MSG_START_INCOMING_TRANSFER); |
| PendingHandoverTransfer transfer = registerInTransferLocked(bluetoothData.device); |
| Bundle transferData = new Bundle(); |
| transferData.putParcelable(HandoverService.BUNDLE_TRANSFER, transfer); |
| msg.setData(transferData); |
| try { |
| mService.send(msg); |
| } catch (RemoteException e) { |
| Log.e(TAG, "Could not connect to handover service"); |
| removeTransferLocked(transfer.id); |
| return null; |
| } |
| } |
| // BT OOB found, whitelist it for incoming OPP data |
| whitelistOppDevice(bluetoothData.device); |
| |
| // return BT OOB record so they can perform handover |
| return (createHandoverSelectMessage(bluetoothActivating)); |
| } |
| |
| public boolean tryHandover(NdefMessage m) { |
| if (m == null) return false; |
| if (mBluetoothAdapter == null) return false; |
| |
| if (DBG) Log.d(TAG, "tryHandover(): " + m.toString()); |
| |
| BluetoothHandoverData handover = parse(m); |
| if (handover == null) return false; |
| if (!handover.valid) return true; |
| |
| synchronized (mLock) { |
| if (mBluetoothAdapter == null) { |
| if (DBG) Log.d(TAG, "BT handover, but BT not available"); |
| return true; |
| } |
| if (!mBound) { |
| Log.e(TAG, "Could not connect to handover service"); |
| return false; |
| } |
| |
| Message msg = Message.obtain(null, HandoverService.MSG_HEADSET_HANDOVER, 0, 0); |
| Bundle headsetData = new Bundle(); |
| headsetData.putParcelable(HandoverService.EXTRA_HEADSET_DEVICE, handover.device); |
| headsetData.putString(HandoverService.EXTRA_HEADSET_NAME, handover.name); |
| msg.setData(headsetData); |
| try { |
| mService.send(msg); |
| } catch (RemoteException e) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| // This starts sending an Uri over BT |
| public void doHandoverUri(Uri[] uris, NdefMessage m) { |
| if (mBluetoothAdapter == null) return; |
| |
| BluetoothHandoverData data = parse(m); |
| if (data != null && data.valid) { |
| // Register a new handover transfer object |
| synchronized (mLock) { |
| if (!mBound) { |
| Log.e(TAG, "Could not connect to handover service"); |
| return; |
| } |
| |
| Message msg = Message.obtain(null, HandoverService.MSG_START_OUTGOING_TRANSFER, 0, 0); |
| PendingHandoverTransfer transfer = registerOutTransferLocked(data, uris); |
| Bundle transferData = new Bundle(); |
| transferData.putParcelable(HandoverService.BUNDLE_TRANSFER, transfer); |
| msg.setData(transferData); |
| try { |
| mService.send(msg); |
| } catch (RemoteException e) { |
| removeTransferLocked(transfer.id); |
| } |
| } |
| } |
| } |
| |
| PendingHandoverTransfer registerInTransferLocked(BluetoothDevice remoteDevice) { |
| PendingHandoverTransfer transfer = new PendingHandoverTransfer( |
| mHandoverTransferId++, true, remoteDevice, false, null); |
| mPendingTransfers.put(transfer.id, transfer); |
| |
| return transfer; |
| } |
| |
| PendingHandoverTransfer registerOutTransferLocked(BluetoothHandoverData data, |
| Uri[] uris) { |
| PendingHandoverTransfer transfer = new PendingHandoverTransfer( |
| mHandoverTransferId++, false, data.device, data.carrierActivating, uris); |
| mPendingTransfers.put(transfer.id, transfer); |
| return transfer; |
| } |
| |
| void removeTransferLocked(int id) { |
| mPendingTransfers.remove(id); |
| } |
| |
| void whitelistOppDevice(BluetoothDevice device) { |
| if (DBG) Log.d(TAG, "Whitelisting " + device + " for BT OPP"); |
| Intent intent = new Intent(ACTION_WHITELIST_DEVICE); |
| intent.putExtra(BluetoothDevice.EXTRA_DEVICE, device); |
| mContext.sendBroadcastAsUser(intent, UserHandle.CURRENT); |
| } |
| |
| boolean isCarrierActivating(NdefRecord handoverRec, byte[] carrierId) { |
| byte[] payload = handoverRec.getPayload(); |
| if (payload == null || payload.length <= 1) return false; |
| // Skip version |
| byte[] payloadNdef = new byte[payload.length - 1]; |
| System.arraycopy(payload, 1, payloadNdef, 0, payload.length - 1); |
| NdefMessage msg; |
| try { |
| msg = new NdefMessage(payloadNdef); |
| } catch (FormatException e) { |
| return false; |
| } |
| |
| for (NdefRecord alt : msg.getRecords()) { |
| byte[] acPayload = alt.getPayload(); |
| if (acPayload != null) { |
| ByteBuffer buf = ByteBuffer.wrap(acPayload); |
| int cps = buf.get() & 0x03; // Carrier Power State is in lower 2 bits |
| int carrierRefLength = buf.get() & 0xFF; |
| if (carrierRefLength != carrierId.length) return false; |
| |
| byte[] carrierRefId = new byte[carrierRefLength]; |
| buf.get(carrierRefId); |
| if (Arrays.equals(carrierRefId, carrierId)) { |
| // Found match, returning whether power state is activating |
| return (cps == CARRIER_POWER_STATE_ACTIVATING); |
| } |
| } |
| } |
| |
| return true; |
| } |
| |
| BluetoothHandoverData parseHandoverSelect(NdefMessage m) { |
| // TODO we could parse this a lot more strictly; right now |
| // we just search for a BT OOB record, and try to cross-reference |
| // the carrier state inside the 'hs' payload. |
| for (NdefRecord oob : m.getRecords()) { |
| if (oob.getTnf() == NdefRecord.TNF_MIME_MEDIA && |
| Arrays.equals(oob.getType(), TYPE_BT_OOB)) { |
| BluetoothHandoverData data = parseBtOob(ByteBuffer.wrap(oob.getPayload())); |
| if (data != null && isCarrierActivating(m.getRecords()[0], oob.getId())) { |
| data.carrierActivating = true; |
| } |
| return data; |
| } |
| } |
| |
| return null; |
| } |
| |
| BluetoothHandoverData parse(NdefMessage m) { |
| NdefRecord r = m.getRecords()[0]; |
| short tnf = r.getTnf(); |
| byte[] type = r.getType(); |
| |
| // Check for BT OOB record |
| if (r.getTnf() == NdefRecord.TNF_MIME_MEDIA && Arrays.equals(r.getType(), TYPE_BT_OOB)) { |
| return parseBtOob(ByteBuffer.wrap(r.getPayload())); |
| } |
| |
| // Check for Handover Select, followed by a BT OOB record |
| if (tnf == NdefRecord.TNF_WELL_KNOWN && |
| Arrays.equals(type, NdefRecord.RTD_HANDOVER_SELECT)) { |
| return parseHandoverSelect(m); |
| } |
| |
| // Check for Nokia BT record, found on some Nokia BH-505 Headsets |
| if (tnf == NdefRecord.TNF_EXTERNAL_TYPE && Arrays.equals(type, TYPE_NOKIA)) { |
| return parseNokia(ByteBuffer.wrap(r.getPayload())); |
| } |
| |
| return null; |
| } |
| |
| BluetoothHandoverData parseNokia(ByteBuffer payload) { |
| BluetoothHandoverData result = new BluetoothHandoverData(); |
| result.valid = false; |
| |
| try { |
| payload.position(1); |
| byte[] address = new byte[6]; |
| payload.get(address); |
| result.device = mBluetoothAdapter.getRemoteDevice(address); |
| result.valid = true; |
| payload.position(14); |
| int nameLength = payload.get(); |
| byte[] nameBytes = new byte[nameLength]; |
| payload.get(nameBytes); |
| result.name = new String(nameBytes, Charset.forName("UTF-8")); |
| } catch (IllegalArgumentException e) { |
| Log.i(TAG, "nokia: invalid BT address"); |
| } catch (BufferUnderflowException e) { |
| Log.i(TAG, "nokia: payload shorter than expected"); |
| } |
| if (result.valid && result.name == null) result.name = ""; |
| return result; |
| } |
| |
| BluetoothHandoverData parseBtOob(ByteBuffer payload) { |
| BluetoothHandoverData result = new BluetoothHandoverData(); |
| result.valid = false; |
| |
| try { |
| payload.position(2); |
| byte[] address = new byte[6]; |
| payload.get(address); |
| // ByteBuffer.order(LITTLE_ENDIAN) doesn't work for |
| // ByteBuffer.get(byte[]), so manually swap order |
| for (int i = 0; i < 3; i++) { |
| byte temp = address[i]; |
| address[i] = address[5 - i]; |
| address[5 - i] = temp; |
| } |
| result.device = mBluetoothAdapter.getRemoteDevice(address); |
| result.valid = true; |
| |
| while (payload.remaining() > 0) { |
| byte[] nameBytes; |
| int len = payload.get(); |
| int type = payload.get(); |
| switch (type) { |
| case 0x08: // short local name |
| nameBytes = new byte[len - 1]; |
| payload.get(nameBytes); |
| result.name = new String(nameBytes, Charset.forName("UTF-8")); |
| break; |
| case 0x09: // long local name |
| if (result.name != null) break; // prefer short name |
| nameBytes = new byte[len - 1]; |
| payload.get(nameBytes); |
| result.name = new String(nameBytes, Charset.forName("UTF-8")); |
| break; |
| default: |
| payload.position(payload.position() + len - 1); |
| break; |
| } |
| } |
| } catch (IllegalArgumentException e) { |
| Log.i(TAG, "BT OOB: invalid BT address"); |
| } catch (BufferUnderflowException e) { |
| Log.i(TAG, "BT OOB: payload shorter than expected"); |
| } |
| if (result.valid && result.name == null) result.name = ""; |
| return result; |
| } |
| |
| static byte[] addressToReverseBytes(String address) { |
| String[] split = address.split(":"); |
| byte[] result = new byte[split.length]; |
| |
| for (int i = 0; i < split.length; i++) { |
| // need to parse as int because parseByte() expects a signed byte |
| result[split.length - 1 - i] = (byte)Integer.parseInt(split[i], 16); |
| } |
| |
| return result; |
| } |
| } |
