BondStateMachine.java revision 11b41d8123241ba8e693e21c4db308bacff23f57 
1/*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.bluetooth.btservice;
18
19import android.bluetooth.BluetoothAdapter;
20import android.bluetooth.BluetoothClass;
21import android.bluetooth.BluetoothProfile;
22import android.bluetooth.BluetoothDevice;
23import com.android.bluetooth.a2dp.A2dpService;
24import com.android.bluetooth.hid.HidService;
25import com.android.bluetooth.hfp.HeadsetService;
26import android.content.Context;
27import android.content.Intent;
28import android.os.Message;
29import android.os.UserHandle;
30import android.util.Log;
31
32import com.android.bluetooth.Utils;
33import com.android.bluetooth.btservice.RemoteDevices.DeviceProperties;
34import com.android.internal.util.State;
35import com.android.internal.util.StateMachine;
36
37import java.util.ArrayList;
38
39/**
40 * This state machine handles Bluetooth Adapter State.
41 * States:
42 *      {@link StableState} :  No device is in bonding / unbonding state.
43 *      {@link PendingCommandState} : Some device is in bonding / unbonding state.
44 * TODO(BT) This class can be removed and this logic moved to the stack.
45 */
46
47final class BondStateMachine extends StateMachine {
48    private static final boolean DBG = false;
49    private static final String TAG = "BluetoothBondStateMachine";
50
51    static final int CREATE_BOND = 1;
52    static final int CANCEL_BOND = 2;
53    static final int REMOVE_BOND = 3;
54    static final int BONDING_STATE_CHANGE = 4;
55    static final int SSP_REQUEST = 5;
56    static final int PIN_REQUEST = 6;
57    static final int BOND_STATE_NONE = 0;
58    static final int BOND_STATE_BONDING = 1;
59    static final int BOND_STATE_BONDED = 2;
60
61    private AdapterService mAdapterService;
62    private AdapterProperties mAdapterProperties;
63    private RemoteDevices mRemoteDevices;
64    private BluetoothAdapter mAdapter;
65
66    private PendingCommandState mPendingCommandState = new PendingCommandState();
67    private StableState mStableState = new StableState();
68
69    private BondStateMachine(AdapterService service,
70            AdapterProperties prop, RemoteDevices remoteDevices) {
71        super("BondStateMachine:");
72        addState(mStableState);
73        addState(mPendingCommandState);
74        mRemoteDevices = remoteDevices;
75        mAdapterService = service;
76        mAdapterProperties = prop;
77        mAdapter = BluetoothAdapter.getDefaultAdapter();
78        setInitialState(mStableState);
79    }
80
81    public static BondStateMachine make(AdapterService service,
82            AdapterProperties prop, RemoteDevices remoteDevices) {
83        Log.d(TAG, "make");
84        BondStateMachine bsm = new BondStateMachine(service, prop, remoteDevices);
85        bsm.start();
86        return bsm;
87    }
88
89    public void doQuit() {
90        quitNow();
91    }
92
93    public void cleanup() {
94        mAdapterService = null;
95        mRemoteDevices = null;
96        mAdapterProperties = null;
97    }
98
99    private class StableState extends State {
100        @Override
101        public void enter() {
102            infoLog("StableState(): Entering Off State");
103        }
104
105        @Override
106        public boolean processMessage(Message msg) {
107
108            BluetoothDevice dev = (BluetoothDevice)msg.obj;
109
110            switch(msg.what) {
111
112              case CREATE_BOND:
113                  createBond(dev, msg.arg1, true);
114                  break;
115              case REMOVE_BOND:
116                  removeBond(dev, true);
117                  break;
118              case BONDING_STATE_CHANGE:
119                int newState = msg.arg1;
120                /* if incoming pairing, transition to pending state */
121                if (newState == BluetoothDevice.BOND_BONDING)
122                {
123                    sendIntent(dev, newState, 0);
124                    transitionTo(mPendingCommandState);
125                }
126                else
127                {
128                    Log.e(TAG, "In stable state, received invalid newState: " + newState);
129                }
130                break;
131
132              case CANCEL_BOND:
133              default:
134                   Log.e(TAG, "Received unhandled state: " + msg.what);
135                   return false;
136            }
137            return true;
138        }
139    }
140
141
142    private class PendingCommandState extends State {
143        private final ArrayList<BluetoothDevice> mDevices =
144            new ArrayList<BluetoothDevice>();
145
146        @Override
147        public void enter() {
148            infoLog("Entering PendingCommandState State");
149            BluetoothDevice dev = (BluetoothDevice)getCurrentMessage().obj;
150        }
151
152        @Override
153        public boolean processMessage(Message msg) {
154
155            BluetoothDevice dev = (BluetoothDevice)msg.obj;
156            DeviceProperties devProp = mRemoteDevices.getDeviceProperties(dev);
157            boolean result = false;
158             if (mDevices.contains(dev) && msg.what != CANCEL_BOND &&
159                   msg.what != BONDING_STATE_CHANGE && msg.what != SSP_REQUEST &&
160                   msg.what != PIN_REQUEST) {
161                 deferMessage(msg);
162                 return true;
163             }
164
165            Intent intent = new Intent(BluetoothDevice.ACTION_PAIRING_REQUEST);
166
167            switch (msg.what) {
168                case CREATE_BOND:
169                    result = createBond(dev, msg.arg1, false);
170                    break;
171                case REMOVE_BOND:
172                    result = removeBond(dev, false);
173                    break;
174                case CANCEL_BOND:
175                    result = cancelBond(dev);
176                    break;
177                case BONDING_STATE_CHANGE:
178                    int newState = msg.arg1;
179                    int reason = getUnbondReasonFromHALCode(msg.arg2);
180                    sendIntent(dev, newState, reason);
181                    if(newState != BluetoothDevice.BOND_BONDING )
182                    {
183                        /* this is either none/bonded, remove and transition */
184                        result = !mDevices.remove(dev);
185                        if (mDevices.isEmpty()) {
186                            // Whenever mDevices is empty, then we need to
187                            // set result=false. Else, we will end up adding
188                            // the device to the list again. This prevents us
189                            // from pairing with a device that we just unpaired
190                            result = false;
191                            transitionTo(mStableState);
192                        }
193                        if (newState == BluetoothDevice.BOND_NONE)
194                        {
195                            // Set the profile Priorities to undefined
196                            clearProfilePriorty(dev);
197                        }
198                        else if (newState == BluetoothDevice.BOND_BONDED)
199                        {
200                           // Do not set profile priority
201                           // Profile priority should be set after SDP completion
202
203                           // Restore the profile priorty settings
204                           //setProfilePriorty(dev);
205                        }
206                    }
207                    else if(!mDevices.contains(dev))
208                        result=true;
209                    break;
210                case SSP_REQUEST:
211                    int passkey = msg.arg1;
212                    int variant = msg.arg2;
213                    sendDisplayPinIntent(devProp.getAddress(), passkey, variant);
214                    break;
215                case PIN_REQUEST:
216                    BluetoothClass btClass = dev.getBluetoothClass();
217                    int btDeviceClass = btClass.getDeviceClass();
218                    if (btDeviceClass == BluetoothClass.Device.PERIPHERAL_KEYBOARD ||
219                         btDeviceClass == BluetoothClass.Device.PERIPHERAL_KEYBOARD_POINTING) {
220                        // Its a keyboard. Follow the HID spec recommendation of creating the
221                        // passkey and displaying it to the user. If the keyboard doesn't follow
222                        // the spec recommendation, check if the keyboard has a fixed PIN zero
223                        // and pair.
224                        //TODO: Maintain list of devices that have fixed pin
225                        // Generate a variable 6-digit PIN in range of 100000-999999
226                        // This is not truly random but good enough.
227                        int pin = 100000 + (int)Math.floor((Math.random() * (999999 - 100000)));
228                        sendDisplayPinIntent(devProp.getAddress(), pin,
229                                 BluetoothDevice.PAIRING_VARIANT_DISPLAY_PIN);
230                        break;
231                    }
232                    //In PIN_REQUEST, there is no passkey to display.So do not send the
233                    //EXTRA_PAIRING_KEY type in the intent( 0 in SendDisplayPinIntent() )
234                    sendDisplayPinIntent(devProp.getAddress(), 0,
235                                          BluetoothDevice.PAIRING_VARIANT_PIN);
236
237                    break;
238                default:
239                    Log.e(TAG, "Received unhandled event:" + msg.what);
240                    return false;
241            }
242            if (result) mDevices.add(dev);
243
244            return true;
245        }
246    }
247
248    private boolean cancelBond(BluetoothDevice dev) {
249        if (dev.getBondState() == BluetoothDevice.BOND_BONDING) {
250            byte[] addr = Utils.getBytesFromAddress(dev.getAddress());
251            if (!mAdapterService.cancelBondNative(addr)) {
252               Log.e(TAG, "Unexpected error while cancelling bond:");
253            } else {
254                return true;
255            }
256        }
257        return false;
258    }
259
260    private boolean removeBond(BluetoothDevice dev, boolean transition) {
261        if (dev.getBondState() == BluetoothDevice.BOND_BONDED) {
262            byte[] addr = Utils.getBytesFromAddress(dev.getAddress());
263            if (!mAdapterService.removeBondNative(addr)) {
264               Log.e(TAG, "Unexpected error while removing bond:");
265            } else {
266                if (transition) transitionTo(mPendingCommandState);
267                return true;
268            }
269
270        }
271        return false;
272    }
273
274    private boolean createBond(BluetoothDevice dev, int transport, boolean transition) {
275        if (dev.getBondState() == BluetoothDevice.BOND_NONE) {
276            infoLog("Bond address is:" + dev);
277            byte[] addr = Utils.getBytesFromAddress(dev.getAddress());
278            if (!mAdapterService.createBondNative(addr, transport)) {
279                sendIntent(dev, BluetoothDevice.BOND_NONE,
280                           BluetoothDevice.UNBOND_REASON_REMOVED);
281                return false;
282            } else if (transition) {
283                transitionTo(mPendingCommandState);
284            }
285            return true;
286        }
287        return false;
288    }
289
290    private void sendDisplayPinIntent(byte[] address, int pin, int variant) {
291        Intent intent = new Intent(BluetoothDevice.ACTION_PAIRING_REQUEST);
292        intent.putExtra(BluetoothDevice.EXTRA_DEVICE, mRemoteDevices.getDevice(address));
293        if (pin != 0) {
294            intent.putExtra(BluetoothDevice.EXTRA_PAIRING_KEY, pin);
295        }
296        intent.putExtra(BluetoothDevice.EXTRA_PAIRING_VARIANT, variant);
297        mAdapterService.sendOrderedBroadcast(intent, mAdapterService.BLUETOOTH_ADMIN_PERM);
298    }
299
300    private void sendIntent(BluetoothDevice device, int newState, int reason) {
301        DeviceProperties devProp = mRemoteDevices.getDeviceProperties(device);
302        int oldState = BluetoothDevice.BOND_NONE;
303        if (devProp != null) {
304            oldState = devProp.getBondState();
305        }
306        if (oldState == newState) return;
307        mAdapterProperties.onBondStateChanged(device, newState);
308
309        Intent intent = new Intent(BluetoothDevice.ACTION_BOND_STATE_CHANGED);
310        intent.putExtra(BluetoothDevice.EXTRA_DEVICE, device);
311        intent.putExtra(BluetoothDevice.EXTRA_BOND_STATE, newState);
312        intent.putExtra(BluetoothDevice.EXTRA_PREVIOUS_BOND_STATE, oldState);
313        if (newState == BluetoothDevice.BOND_NONE)
314            intent.putExtra(BluetoothDevice.EXTRA_REASON, reason);
315        mAdapterService.sendBroadcastAsUser(intent, UserHandle.ALL,
316                AdapterService.BLUETOOTH_PERM);
317        infoLog("Bond State Change Intent:" + device + " OldState: " + oldState
318                + " NewState: " + newState);
319    }
320
321    void bondStateChangeCallback(int status, byte[] address, int newState) {
322        BluetoothDevice device = mRemoteDevices.getDevice(address);
323
324        if (device == null) {
325            infoLog("No record of the device:" + device);
326            // This device will be added as part of the BONDING_STATE_CHANGE intent processing
327            // in sendIntent above
328            device = mAdapter.getRemoteDevice(Utils.getAddressStringFromByte(address));
329        }
330
331        infoLog("bondStateChangeCallback: Status: " + status + " Address: " + device
332                + " newState: " + newState);
333
334        Message msg = obtainMessage(BONDING_STATE_CHANGE);
335        msg.obj = device;
336
337        if (newState == BOND_STATE_BONDED)
338            msg.arg1 = BluetoothDevice.BOND_BONDED;
339        else if (newState == BOND_STATE_BONDING)
340            msg.arg1 = BluetoothDevice.BOND_BONDING;
341        else
342            msg.arg1 = BluetoothDevice.BOND_NONE;
343        msg.arg2 = status;
344
345        sendMessage(msg);
346    }
347
348    void sspRequestCallback(byte[] address, byte[] name, int cod, int pairingVariant,
349            int passkey) {
350        //TODO(BT): Get wakelock and update name and cod
351        BluetoothDevice bdDevice = mRemoteDevices.getDevice(address);
352        if (bdDevice == null) {
353            mRemoteDevices.addDeviceProperties(address);
354        }
355        infoLog("sspRequestCallback: " + address + " name: " + name + " cod: " +
356                cod + " pairingVariant " + pairingVariant + " passkey: " + passkey);
357        int variant;
358        boolean displayPasskey = false;
359        switch(pairingVariant) {
360
361            case AbstractionLayer.BT_SSP_VARIANT_PASSKEY_CONFIRMATION :
362                variant = BluetoothDevice.PAIRING_VARIANT_PASSKEY_CONFIRMATION;
363                displayPasskey = true;
364            break;
365
366            case AbstractionLayer.BT_SSP_VARIANT_CONSENT :
367                variant = BluetoothDevice.PAIRING_VARIANT_CONSENT;
368            break;
369
370            case AbstractionLayer.BT_SSP_VARIANT_PASSKEY_ENTRY :
371                variant = BluetoothDevice.PAIRING_VARIANT_PASSKEY;
372            break;
373
374            case AbstractionLayer.BT_SSP_VARIANT_PASSKEY_NOTIFICATION :
375                variant = BluetoothDevice.PAIRING_VARIANT_DISPLAY_PASSKEY;
376                displayPasskey = true;
377            break;
378
379            default:
380                errorLog("SSP Pairing variant not present");
381                return;
382        }
383        BluetoothDevice device = mRemoteDevices.getDevice(address);
384        if (device == null) {
385           warnLog("Device is not known for:" + Utils.getAddressStringFromByte(address));
386           mRemoteDevices.addDeviceProperties(address);
387           device = mRemoteDevices.getDevice(address);
388        }
389
390        Message msg = obtainMessage(SSP_REQUEST);
391        msg.obj = device;
392        if(displayPasskey)
393            msg.arg1 = passkey;
394        msg.arg2 = variant;
395        sendMessage(msg);
396    }
397
398    void pinRequestCallback(byte[] address, byte[] name, int cod) {
399        //TODO(BT): Get wakelock and update name and cod
400        BluetoothDevice bdDevice = mRemoteDevices.getDevice(address);
401        if (bdDevice == null) {
402            mRemoteDevices.addDeviceProperties(address);
403        }
404        infoLog("pinRequestCallback: " + address + " name:" + name + " cod:" +
405                cod);
406
407        Message msg = obtainMessage(PIN_REQUEST);
408        msg.obj = bdDevice;
409
410        sendMessage(msg);
411    }
412
413    private void setProfilePriorty (BluetoothDevice device){
414        HidService hidService = HidService.getHidService();
415        A2dpService a2dpService = A2dpService.getA2dpService();
416        HeadsetService headsetService = HeadsetService.getHeadsetService();
417
418        if ((hidService != null) &&
419            (hidService.getPriority(device) == BluetoothProfile.PRIORITY_UNDEFINED)){
420            hidService.setPriority(device,BluetoothProfile.PRIORITY_ON);
421        }
422
423        if ((a2dpService != null) &&
424            (a2dpService.getPriority(device) == BluetoothProfile.PRIORITY_UNDEFINED)){
425            a2dpService.setPriority(device,BluetoothProfile.PRIORITY_ON);
426        }
427
428        if ((headsetService != null) &&
429            (headsetService.getPriority(device) == BluetoothProfile.PRIORITY_UNDEFINED)){
430            headsetService.setPriority(device,BluetoothProfile.PRIORITY_ON);
431        }
432    }
433
434    private void clearProfilePriorty (BluetoothDevice device){
435        HidService hidService = HidService.getHidService();
436        A2dpService a2dpService = A2dpService.getA2dpService();
437        HeadsetService headsetService = HeadsetService.getHeadsetService();
438
439        if (hidService != null)
440            hidService.setPriority(device,BluetoothProfile.PRIORITY_UNDEFINED);
441        if(a2dpService != null)
442            a2dpService.setPriority(device,BluetoothProfile.PRIORITY_UNDEFINED);
443        if(headsetService != null)
444            headsetService.setPriority(device,BluetoothProfile.PRIORITY_UNDEFINED);
445    }
446
447    private void infoLog(String msg) {
448        Log.i(TAG, msg);
449    }
450
451    private void errorLog(String msg) {
452        Log.e(TAG, msg);
453    }
454
455    private void warnLog(String msg) {
456        Log.w(TAG, msg);
457    }
458
459    private int getUnbondReasonFromHALCode (int reason) {
460        if (reason == AbstractionLayer.BT_STATUS_SUCCESS)
461            return BluetoothDevice.BOND_SUCCESS;
462        else if (reason == AbstractionLayer.BT_STATUS_RMT_DEV_DOWN)
463            return BluetoothDevice.UNBOND_REASON_REMOTE_DEVICE_DOWN;
464        else if (reason == AbstractionLayer.BT_STATUS_AUTH_FAILURE)
465            return BluetoothDevice.UNBOND_REASON_AUTH_FAILED;
466        else if (reason == AbstractionLayer.BT_STATUS_AUTH_REJECTED)
467            return BluetoothDevice.UNBOND_REASON_AUTH_REJECTED;
468        else if (reason == AbstractionLayer.BT_STATUS_AUTH_TIMEOUT)
469            return BluetoothDevice.UNBOND_REASON_AUTH_TIMEOUT;
470
471        /* default */
472        return BluetoothDevice.UNBOND_REASON_REMOVED;
473    }
474}
475