1 /*
2  * Copyright (C) 2014 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 
17 package com.android.services.telephony;
18 
19 import android.net.Uri;
20 import android.os.AsyncResult;
21 import android.os.Bundle;
22 import android.os.Handler;
23 import android.os.Message;
24 import android.os.SystemClock;
25 import android.telecom.PhoneAccount;
26 import android.telecom.PhoneAccountHandle;
27 import android.telecom.TelecomManager;
28 import android.telephony.ims.ImsCallProfile;
29 import android.text.TextUtils;
30 
31 import com.android.ims.ImsCall;
32 import com.android.internal.telephony.Call;
33 import com.android.internal.telephony.CallStateException;
34 import com.android.internal.telephony.Connection;
35 import com.android.internal.telephony.GsmCdmaPhone;
36 import com.android.internal.telephony.Phone;
37 import com.android.internal.telephony.PhoneConstants;
38 import com.android.internal.telephony.cdma.CdmaCallWaitingNotification;
39 import com.android.internal.telephony.imsphone.ImsExternalCallTracker;
40 import com.android.internal.telephony.imsphone.ImsExternalConnection;
41 import com.android.internal.telephony.imsphone.ImsPhone;
42 import com.android.internal.telephony.imsphone.ImsPhoneCallTracker;
43 import com.android.internal.telephony.imsphone.ImsPhoneConnection;
44 import com.android.phone.NumberVerificationManager;
45 import com.android.phone.PhoneUtils;
46 import com.android.phone.callcomposer.CallComposerPictureManager;
47 import com.android.telephony.Rlog;
48 
49 import java.util.List;
50 import java.util.Objects;
51 import java.util.stream.Collectors;
52 
53 /**
54  * Listens to incoming-call events from the associated phone object and notifies Telecom upon each
55  * occurence. One instance of these exists for each of the telephony-based call services.
56  */
57 final class PstnIncomingCallNotifier {
58     private static final String LOG_TAG = "PstnIncomingCallNotifier";
59 
60     /** New ringing connection event code. */
61     private static final int EVENT_NEW_RINGING_CONNECTION = 100;
62     private static final int EVENT_CDMA_CALL_WAITING = 101;
63     private static final int EVENT_UNKNOWN_CONNECTION = 102;
64 
65     /**
66      * The max amount of time to wait before hanging up a call that was for number verification.
67      *
68      * The delay is so that the remote end has time to hang up the call after receiving the
69      * verification signal so that the call doesn't go to voicemail.
70      */
71     private static final int MAX_NUMBER_VERIFICATION_HANGUP_DELAY_MILLIS = 10000;
72 
73     /**
74      * Hardcoded extra for a call that's used to provide metrics information to the dialer app.
75      */
76     private static final String EXTRA_CALL_CREATED_TIME_MILLIS =
77             "android.telecom.extra.CALL_CREATED_TIME_MILLIS";
78 
79     /** The phone object to listen to. */
80     private final Phone mPhone;
81 
82     /**
83      * Used to listen to events from {@link #mPhone}.
84      */
85     private final Handler mHandler = new Handler() {
86         @Override
87         public void handleMessage(Message msg) {
88             switch(msg.what) {
89                 case EVENT_NEW_RINGING_CONNECTION:
90                     handleNewRingingConnection((AsyncResult) msg.obj);
91                     break;
92                 case EVENT_CDMA_CALL_WAITING:
93                     handleCdmaCallWaiting((AsyncResult) msg.obj);
94                     break;
95                 case EVENT_UNKNOWN_CONNECTION:
96                     handleNewUnknownConnection((AsyncResult) msg.obj);
97                     break;
98                 default:
99                     break;
100             }
101         }
102 
103         @Override
104         public String toString() {
105             return String.format("[PstnIncomingCallNotifierHandler; phoneId=[%s]",
106                     getPhoneIdAsString());
107         }
108     };
109 
110     /**
111      * Persists the specified parameters and starts listening to phone events.
112      *
113      * @param phone The phone object for listening to incoming calls.
114      */
PstnIncomingCallNotifier(Phone phone)115     PstnIncomingCallNotifier(Phone phone) {
116         if (phone == null) {
117             throw new NullPointerException();
118         }
119 
120         mPhone = phone;
121 
122         registerForNotifications();
123     }
124 
teardown()125     void teardown() {
126         unregisterForNotifications();
127     }
128 
129     /**
130      * Register for notifications from the base phone.
131      */
registerForNotifications()132     private void registerForNotifications() {
133         if (mPhone != null) {
134             Log.i(this, "Registering: [%s]", getPhoneIdAsString());
135             mPhone.registerForNewRingingConnection(mHandler, EVENT_NEW_RINGING_CONNECTION, null);
136             mPhone.registerForCallWaiting(mHandler, EVENT_CDMA_CALL_WAITING, null);
137             mPhone.registerForUnknownConnection(mHandler, EVENT_UNKNOWN_CONNECTION, null);
138         }
139     }
140 
unregisterForNotifications()141     private void unregisterForNotifications() {
142         if (mPhone != null) {
143             Log.i(this, "Unregistering: [%s]", getPhoneIdAsString());
144             mPhone.unregisterForNewRingingConnection(mHandler);
145             mPhone.unregisterForCallWaiting(mHandler);
146             mPhone.unregisterForUnknownConnection(mHandler);
147         }
148     }
149 
150     /**
151      * Verifies the incoming call and triggers sending the incoming-call intent to Telecom.
152      *
153      * @param asyncResult The result object from the new ringing event.
154      */
handleNewRingingConnection(AsyncResult asyncResult)155     private void handleNewRingingConnection(AsyncResult asyncResult) {
156         Log.i(this, "handleNewRingingConnection: phoneId=[%s]", getPhoneIdAsString());
157         Connection connection = (Connection) asyncResult.result;
158         if (connection != null) {
159             Call call = connection.getCall();
160             // Check if we have a pending number verification request.
161             if (connection.getAddress() != null) {
162                 if (NumberVerificationManager.getInstance()
163                         .checkIncomingCall(connection.getAddress())) {
164                     // Disconnect the call if it matches, after a delay
165                     mHandler.postDelayed(() -> {
166                         try {
167                             connection.hangup();
168                         } catch (CallStateException e) {
169                             Log.i(this, "Remote end hung up call verification call");
170                         }
171                         // TODO: use an app-supplied delay (needs new API), not to exceed the
172                         // existing max.
173                     }, MAX_NUMBER_VERIFICATION_HANGUP_DELAY_MILLIS);
174                     return;
175                 }
176             }
177 
178             // Final verification of the ringing state before sending the intent to Telecom.
179             if (call != null && call.getState().isRinging()) {
180                 sendIncomingCallIntent(connection);
181             }
182         }
183     }
184 
handleCdmaCallWaiting(AsyncResult asyncResult)185     private void handleCdmaCallWaiting(AsyncResult asyncResult) {
186         Log.i(this, "handleCdmaCallWaiting: phoneId=[%s]", getPhoneIdAsString());
187         CdmaCallWaitingNotification ccwi = (CdmaCallWaitingNotification) asyncResult.result;
188         Call call = mPhone.getRingingCall();
189         if (call.getState() == Call.State.WAITING) {
190             Connection connection = call.getLatestConnection();
191             if (connection != null) {
192                 String number = connection.getAddress();
193                 int presentation = connection.getNumberPresentation();
194 
195                 if (presentation != PhoneConstants.PRESENTATION_ALLOWED
196                         && presentation == ccwi.numberPresentation) {
197                     // Presentation of number not allowed, but the presentation of the Connection
198                     // and the call waiting presentation match.
199                     Log.i(this, "handleCdmaCallWaiting: inform telecom of waiting call; "
200                             + "presentation = %d", presentation);
201                     sendIncomingCallIntent(connection);
202                 } else if (!TextUtils.isEmpty(number) && Objects.equals(number, ccwi.number)) {
203                     // Presentation of the number is allowed, so we ensure the number matches the
204                     // one in the call waiting information.
205                     Log.i(this, "handleCdmaCallWaiting: inform telecom of waiting call; "
206                             + "number = %s", Rlog.pii(LOG_TAG, number));
207                     sendIncomingCallIntent(connection);
208                 } else {
209                     Log.i(this, "handleCdmaCallWaiting: presentation or number do not match, not"
210                             + " informing telecom of call: %s", ccwi);
211                 }
212             }
213         }
214     }
215 
handleNewUnknownConnection(AsyncResult asyncResult)216     private void handleNewUnknownConnection(AsyncResult asyncResult) {
217         Log.i(this, "handleNewUnknownConnection: phoneId=[%s]", getPhoneIdAsString());
218         if (!(asyncResult.result instanceof Connection)) {
219             Log.i(this, "handleNewUnknownConnection called with non-Connection object");
220             return;
221         }
222         Connection connection = (Connection) asyncResult.result;
223         if (connection != null) {
224             // Because there is a handler between telephony and here, it causes this action to be
225             // asynchronous which means that the call can switch to DISCONNECTED by the time it gets
226             // to this code. Check here to ensure we are not adding a disconnected or IDLE call.
227             Call.State state = connection.getState();
228             if (state == Call.State.DISCONNECTED || state == Call.State.IDLE) {
229                 Log.i(this, "Skipping new unknown connection because it is idle. " + connection);
230                 return;
231             }
232 
233             Call call = connection.getCall();
234             if (call != null && call.getState().isAlive()) {
235                 addNewUnknownCall(connection);
236             } else {
237                 Log.i(this, "Skipping new unknown connection because its call is null or dead."
238                         + " connection=" + connection);
239             }
240         }
241     }
242 
addNewUnknownCall(Connection connection)243     private void addNewUnknownCall(Connection connection) {
244         Log.i(this, "addNewUnknownCall, connection is: %s", connection);
245 
246         if (!maybeSwapAnyWithUnknownConnection(connection)) {
247             Log.i(this, "determined new connection is: %s", connection);
248             Bundle extras = new Bundle();
249             if (connection.getNumberPresentation() == TelecomManager.PRESENTATION_ALLOWED &&
250                     !TextUtils.isEmpty(connection.getAddress())) {
251                 Uri uri = Uri.fromParts(PhoneAccount.SCHEME_TEL, connection.getAddress(), null);
252                 extras.putParcelable(TelecomManager.EXTRA_UNKNOWN_CALL_HANDLE, uri);
253             }
254             // ImsExternalConnections are keyed by a unique mCallId; include this as an extra on
255             // the call to addNewUknownCall in Telecom.  This way when the request comes back to the
256             // TelephonyConnectionService, we will be able to determine which unknown connection is
257             // being added.
258             if (connection instanceof ImsExternalConnection) {
259                 ImsExternalConnection externalConnection = (ImsExternalConnection) connection;
260                 extras.putInt(ImsExternalCallTracker.EXTRA_IMS_EXTERNAL_CALL_ID,
261                         externalConnection.getCallId());
262             }
263 
264             // Specifies the time the call was added. This is used by the dialer for analytics.
265             extras.putLong(EXTRA_CALL_CREATED_TIME_MILLIS, SystemClock.elapsedRealtime());
266 
267             PhoneAccountHandle handle = findCorrectPhoneAccountHandle();
268             if (handle == null) {
269                 try {
270                     connection.hangup();
271                 } catch (CallStateException e) {
272                     // connection already disconnected. Do nothing
273                 }
274             } else {
275                 TelecomManager tm = mPhone.getContext().getSystemService(TelecomManager.class);
276                 tm.addNewUnknownCall(handle, extras);
277             }
278         } else {
279             Log.i(this, "swapped an old connection, new one is: %s", connection);
280         }
281     }
282 
283     /**
284      * Sends the incoming call intent to telecom.
285      */
sendIncomingCallIntent(Connection connection)286     private void sendIncomingCallIntent(Connection connection) {
287         Bundle extras = new Bundle();
288         if (connection.getNumberPresentation() == TelecomManager.PRESENTATION_ALLOWED &&
289                 !TextUtils.isEmpty(connection.getAddress())) {
290             Uri uri = Uri.fromParts(PhoneAccount.SCHEME_TEL, connection.getAddress(), null);
291             extras.putParcelable(TelecomManager.EXTRA_INCOMING_CALL_ADDRESS, uri);
292         }
293 
294         // Specifies the time the call was added. This is used by the dialer for analytics.
295         extras.putLong(EXTRA_CALL_CREATED_TIME_MILLIS, SystemClock.elapsedRealtime());
296 
297         if (connection.getPhoneType() == PhoneConstants.PHONE_TYPE_IMS) {
298             if (((ImsPhoneConnection) connection).isRttEnabledForCall()) {
299                 extras.putBoolean(TelecomManager.EXTRA_START_CALL_WITH_RTT, true);
300             }
301             if (((ImsPhoneConnection) connection).isIncomingCallAutoRejected()) {
302                 extras.putString(TelecomManager.EXTRA_CALL_DISCONNECT_MESSAGE,
303                         TelecomManager.CALL_AUTO_DISCONNECT_MESSAGE_STRING);
304             }
305             ImsCall imsCall = ((ImsPhoneConnection) connection).getImsCall();
306             if (imsCall != null) {
307                 ImsCallProfile imsCallProfile = imsCall.getCallProfile();
308                 if (imsCallProfile != null) {
309                     if (CallComposerPictureManager.sTestMode) {
310                         imsCallProfile.setCallExtra(ImsCallProfile.EXTRA_PICTURE_URL,
311                                 CallComposerPictureManager.FAKE_SERVER_URL);
312                         imsCallProfile.setCallExtraInt(ImsCallProfile.EXTRA_PRIORITY,
313                                 TelecomManager.PRIORITY_URGENT);
314                         imsCallProfile.setCallExtra(ImsCallProfile.EXTRA_CALL_SUBJECT,
315                                 CallComposerPictureManager.FAKE_SUBJECT);
316                         imsCallProfile.setCallExtraParcelable(ImsCallProfile.EXTRA_LOCATION,
317                                 CallComposerPictureManager.FAKE_LOCATION);
318                     }
319 
320                     extras.putInt(TelecomManager.EXTRA_PRIORITY,
321                             imsCallProfile.getCallExtraInt(ImsCallProfile.EXTRA_PRIORITY));
322                     extras.putString(TelecomManager.EXTRA_CALL_SUBJECT,
323                             imsCallProfile.getCallExtra(ImsCallProfile.EXTRA_CALL_SUBJECT));
324                     extras.putParcelable(TelecomManager.EXTRA_LOCATION,
325                             imsCallProfile.getCallExtraParcelable(ImsCallProfile.EXTRA_LOCATION));
326                     if (!TextUtils.isEmpty(
327                             imsCallProfile.getCallExtra(ImsCallProfile.EXTRA_PICTURE_URL))) {
328                         extras.putBoolean(TelecomManager.EXTRA_HAS_PICTURE, true);
329                     }
330                 }
331             }
332         }
333 
334         PhoneAccountHandle handle = findCorrectPhoneAccountHandle();
335         if (handle == null) {
336             try {
337                 connection.hangup();
338             } catch (CallStateException e) {
339                 // connection already disconnected. Do nothing
340             }
341             Log.wtf(LOG_TAG, "sendIncomingCallIntent: failed to add new call because no phone"
342                     + " account could be found for the call");
343         } else {
344             TelecomManager tm = mPhone.getContext().getSystemService(TelecomManager.class);
345             try {
346                 if (connection.isMultiparty()) {
347                     tm.addNewIncomingConference(handle, extras);
348                 } else {
349                     tm.addNewIncomingCall(handle, extras);
350                 }
351             } catch (SecurityException se) {
352                 // If we get a security exception, the most likely cause is:
353                 // "This PhoneAccountHandle is not registered for this user"
354                 // If this happens, then it means that for whatever reason the phone account which
355                 // we are trying to use to add the new incoming call no longer exists in Telecom.
356                 // This can happen if the handle of the phone account changes.  The likely root
357                 // cause of this would be a change in active SIM profile for an MVNO style carrier
358                 // which aggregates multiple carriers together.
359 
360                 // We will log a list of the available handles ourselves here; PhoneAccountHandle
361                 // oscures the ID in the toString.  Rlog.pii will do a secure hash on userdebug
362                 // builds so at least we could tell if the handle we tried is different from the one
363                 // which we attempted to use.
364                 List<PhoneAccountHandle> handles = tm.getCallCapablePhoneAccounts();
365                 String availableHandles = handles.stream()
366                         .map(h -> "[" + h.getComponentName() + " "
367                                 + Rlog.pii(LOG_TAG, h.getId()) + "]")
368                         .collect(Collectors.joining(","));
369                 String attemptedHandle = "[" + handle.getComponentName() + " "
370                         + Rlog.pii(LOG_TAG, handle.getId()) + "]";
371                 Log.wtf(LOG_TAG, "sendIncomingCallIntent: failed to add new call " + connection
372                         + " because the handle " + attemptedHandle
373                         + " is not in the list of registered handles " + availableHandles
374                         + " - call was rejected.");
375 
376                 // Since the phone account handle we're trying to use is not valid, we have no other
377                 // recourse but to reject the incoming call.
378                 try {
379                     connection.hangup();
380                 } catch (CallStateException e) {
381                     // connection already disconnected. Do nothing
382                 }
383             }
384         }
385     }
386 
387     /**
388      * Returns the PhoneAccount associated with this {@code PstnIncomingCallNotifier}'s phone. On a
389      * device with No SIM or in airplane mode, it can return an Emergency-only PhoneAccount. If no
390      * PhoneAccount is registered with telecom, return null.
391      * @return A valid PhoneAccountHandle that is registered to Telecom or null if there is none
392      * registered.
393      */
findCorrectPhoneAccountHandle()394     private PhoneAccountHandle findCorrectPhoneAccountHandle() {
395         TelecomAccountRegistry telecomAccountRegistry = TelecomAccountRegistry.getInstance(null);
396         // Check to see if a SIM PhoneAccountHandle Exists for the Call.
397         PhoneAccountHandle handle = telecomAccountRegistry.getPhoneAccountHandleForSubId(
398                 mPhone.getSubId());
399         if (telecomAccountRegistry.hasAccountEntryForPhoneAccount(handle)) {
400             return handle;
401         }
402         // The PhoneAccountHandle does not match any PhoneAccount registered in Telecom.
403         // This is only known to happen if there is no SIM card in the device and the device
404         // receives an MT call while in ECM. Use the Emergency PhoneAccount to receive the account
405         // if it exists.
406         PhoneAccountHandle emergencyHandle =
407                 PhoneUtils.makePstnPhoneAccountHandleWithPrefix(mPhone,
408                         "", true, mPhone.getUserHandle());
409         if(telecomAccountRegistry.hasAccountEntryForPhoneAccount(emergencyHandle)) {
410             Log.i(this, "Receiving MT call in ECM. Using Emergency PhoneAccount Instead.");
411             return emergencyHandle;
412         }
413         Log.i(this, "PhoneAccount not found.");
414         return null;
415     }
416 
417     /**
418      * Define cait.Connection := com.android.internal.telephony.Connection
419      *
420      * Given a previously unknown cait.Connection, check to see if it's likely a replacement for
421      * another cait.Connnection we already know about. If it is, then we silently swap it out
422      * underneath within the relevant {@link TelephonyConnection}, using
423      * {@link TelephonyConnection#setOriginalConnection(Connection)}, and return {@code true}.
424      * Otherwise, we return {@code false}.
425      */
maybeSwapAnyWithUnknownConnection(Connection unknown)426     private boolean maybeSwapAnyWithUnknownConnection(Connection unknown) {
427         if (!unknown.isIncoming()) {
428             TelecomAccountRegistry registry = TelecomAccountRegistry.getInstance(null);
429             if (registry != null) {
430                 TelephonyConnectionService service = registry.getTelephonyConnectionService();
431                 if (service != null) {
432                     for (android.telecom.Connection telephonyConnection : service
433                             .getAllConnections()) {
434                         if (telephonyConnection instanceof TelephonyConnection) {
435                             if (maybeSwapWithUnknownConnection(
436                                     (TelephonyConnection) telephonyConnection,
437                                     unknown)) {
438                                 return true;
439                             }
440                         }
441                     }
442                 }
443             }
444         }
445         return false;
446     }
447 
maybeSwapWithUnknownConnection( TelephonyConnection telephonyConnection, Connection unknown)448     private boolean maybeSwapWithUnknownConnection(
449             TelephonyConnection telephonyConnection,
450             Connection unknown) {
451         Connection original = telephonyConnection.getOriginalConnection();
452         if (original != null && !original.isIncoming()
453                 && Objects.equals(original.getAddress(), unknown.getAddress())) {
454             // If the new unknown connection is an external connection, don't swap one with an
455             // actual connection.  This means a call got pulled away.  We want the actual connection
456             // to disconnect.
457             if (unknown instanceof ImsExternalConnection &&
458                     !(telephonyConnection
459                             .getOriginalConnection() instanceof ImsExternalConnection)) {
460                 Log.i(this, "maybeSwapWithUnknownConnection - not swapping "
461                         + "regular connection with external connection.");
462                 return false;
463             }
464 
465             Log.i(this, "maybeSwapWithUnknownConnection: swapping %s with %s", original, unknown);
466             telephonyConnection.setOriginalConnection(unknown);
467 
468             // Do not call hang up if the original connection is an ImsExternalConnection, it is
469             // not supported.
470             if (original instanceof ImsExternalConnection) {
471                 return true;
472             }
473             // If the connection we're replacing was a GSM or CDMA connection, call upon the call
474             // tracker to perform cleanup of calls.  This ensures that we don't end up with a
475             // call stuck in the call tracker preventing other calls from being placed.
476             if (original.getCall() != null && original.getCall().getPhone() != null &&
477                     original.getCall().getPhone() instanceof GsmCdmaPhone) {
478 
479                 GsmCdmaPhone phone = (GsmCdmaPhone) original.getCall().getPhone();
480                 phone.getCallTracker().cleanupCalls();
481                 Log.i(this, "maybeSwapWithUnknownConnection - Invoking call tracker cleanup "
482                         + "for connection: " + original);
483             } else if (original.getCall() != null && original.getCall().getPhone() != null
484                     && original.getCall().getPhone() instanceof ImsPhone
485                     && original instanceof ImsPhoneConnection) {
486                 // We're replacing an existing ImsPhoneConnection; ensure we don't orhan the
487                 // original connection.
488                 ImsPhone phone = (ImsPhone) original.getCall().getPhone();
489                 ImsPhoneCallTracker tracker = (ImsPhoneCallTracker) phone.getCallTracker();
490                 tracker.cleanupAndRemoveConnection((ImsPhoneConnection) original);
491                 Log.i(this, "maybeSwapWithUnknownConnection - cleanup/remove: " + original);
492             }
493             return true;
494         }
495         return false;
496     }
497 
getPhoneIdAsString()498     private String getPhoneIdAsString() {
499         if (mPhone == null) {
500             return "-1";
501         }
502         return String.valueOf(mPhone.getPhoneId());
503     }
504 }