/* * Copyright (C) 2011 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.cellbroadcastreceiver; import android.app.ActivityManagerNative; import android.app.Notification; import android.app.NotificationManager; import android.app.PendingIntent; import android.app.Service; import android.content.Context; import android.content.Intent; import android.content.SharedPreferences; import android.os.Binder; import android.os.Bundle; import android.os.IBinder; import android.os.PersistableBundle; import android.os.RemoteException; import android.os.SystemClock; import android.os.UserHandle; import android.preference.PreferenceManager; import android.provider.Telephony; import android.telephony.CarrierConfigManager; import android.telephony.CellBroadcastMessage; import android.telephony.SmsCbCmasInfo; import android.telephony.SmsCbEtwsInfo; import android.telephony.SmsCbLocation; import android.telephony.SmsCbMessage; import android.telephony.SubscriptionManager; import android.util.Log; import com.android.cellbroadcastreceiver.CellBroadcastAlertAudio.ToneType; import com.android.cellbroadcastreceiver.CellBroadcastOtherChannelsManager.CellBroadcastChannelRange; import com.android.internal.annotations.VisibleForTesting; import com.android.internal.telephony.PhoneConstants; import java.util.ArrayList; import java.util.LinkedHashMap; import java.util.Locale; import static android.text.format.DateUtils.DAY_IN_MILLIS; /** * This service manages the display and animation of broadcast messages. * Emergency messages display with a flashing animated exclamation mark icon, * and an alert tone is played when the alert is first shown to the user * (but not when the user views a previously received broadcast). */ public class CellBroadcastAlertService extends Service { private static final String TAG = "CBAlertService"; /** Intent action to display alert dialog/notification, after verifying the alert is new. */ static final String SHOW_NEW_ALERT_ACTION = "cellbroadcastreceiver.SHOW_NEW_ALERT"; /** Use the same notification ID for non-emergency alerts. */ static final int NOTIFICATION_ID = 1; /** Sticky broadcast for latest area info broadcast received. */ static final String CB_AREA_INFO_RECEIVED_ACTION = "android.cellbroadcastreceiver.CB_AREA_INFO_RECEIVED"; /** * Default message expiration time is 24 hours. Same message arrives within 24 hours will be * treated as a duplicate. */ private static final long DEFAULT_EXPIRATION_TIME = DAY_IN_MILLIS; /** * Container for service category, serial number, location, body hash code, and ETWS primary/ * secondary information for duplication detection. */ private static final class MessageServiceCategoryAndScope { private final int mServiceCategory; private final int mSerialNumber; private final SmsCbLocation mLocation; private final int mBodyHash; private final boolean mIsEtwsPrimary; MessageServiceCategoryAndScope(int serviceCategory, int serialNumber, SmsCbLocation location, int bodyHash, boolean isEtwsPrimary) { mServiceCategory = serviceCategory; mSerialNumber = serialNumber; mLocation = location; mBodyHash = bodyHash; mIsEtwsPrimary = isEtwsPrimary; } @Override public int hashCode() { return mLocation.hashCode() + 5 * mServiceCategory + 7 * mSerialNumber + 13 * mBodyHash + 17 * Boolean.hashCode(mIsEtwsPrimary); } @Override public boolean equals(Object o) { if (o == this) { return true; } if (o instanceof MessageServiceCategoryAndScope) { MessageServiceCategoryAndScope other = (MessageServiceCategoryAndScope) o; return (mServiceCategory == other.mServiceCategory && mSerialNumber == other.mSerialNumber && mLocation.equals(other.mLocation) && mBodyHash == other.mBodyHash && mIsEtwsPrimary == other.mIsEtwsPrimary); } return false; } @Override public String toString() { return "{mServiceCategory: " + mServiceCategory + " serial number: " + mSerialNumber + " location: " + mLocation.toString() + " body hash: " + mBodyHash + " mIsEtwsPrimary: " + mIsEtwsPrimary + "}"; } } /** Maximum number of message IDs to save before removing the oldest message ID. */ private static final int MAX_MESSAGE_ID_SIZE = 1024; /** Linked hash map of the message identities for duplication detection purposes. The key is the * the collection of different message keys used for duplication detection, and the value * is the timestamp of message arriving time. Some carriers may require shorter expiration time. */ private static final LinkedHashMap sMessagesMap = new LinkedHashMap<>(); @Override public int onStartCommand(Intent intent, int flags, int startId) { String action = intent.getAction(); Log.d(TAG, "onStartCommand: " + action); if (Telephony.Sms.Intents.SMS_EMERGENCY_CB_RECEIVED_ACTION.equals(action) || Telephony.Sms.Intents.SMS_CB_RECEIVED_ACTION.equals(action)) { handleCellBroadcastIntent(intent); } else if (SHOW_NEW_ALERT_ACTION.equals(action)) { try { if (UserHandle.myUserId() == ActivityManagerNative.getDefault().getCurrentUser().id) { showNewAlert(intent); } else { Log.d(TAG,"Not active user, ignore the alert display"); } } catch (RemoteException e) { e.printStackTrace(); } } else { Log.e(TAG, "Unrecognized intent action: " + action); } return START_NOT_STICKY; } /** * Get the carrier specific message duplicate expiration time. * * @param subId Subscription index * @return The expiration time in milliseconds. Small values like 0 (or negative values) * indicate expiration immediately (meaning the duplicate will always be displayed), while large * values indicate the duplicate will always be ignored. The default value would be 24 hours. */ private long getDuplicateExpirationTime(int subId) { CarrierConfigManager configManager = (CarrierConfigManager) getApplicationContext().getSystemService(Context.CARRIER_CONFIG_SERVICE); Log.d(TAG, "manager = " + configManager); if (configManager == null) { Log.e(TAG, "carrier config is not available."); return DEFAULT_EXPIRATION_TIME; } PersistableBundle b = configManager.getConfigForSubId(subId); if (b == null) { Log.e(TAG, "expiration key does not exist."); return DEFAULT_EXPIRATION_TIME; } long time = b.getLong(CarrierConfigManager.KEY_MESSAGE_EXPIRATION_TIME_LONG, DEFAULT_EXPIRATION_TIME); return time; } private void handleCellBroadcastIntent(Intent intent) { Bundle extras = intent.getExtras(); if (extras == null) { Log.e(TAG, "received SMS_CB_RECEIVED_ACTION with no extras!"); return; } SmsCbMessage message = (SmsCbMessage) extras.get("message"); if (message == null) { Log.e(TAG, "received SMS_CB_RECEIVED_ACTION with no message extra"); return; } final CellBroadcastMessage cbm = new CellBroadcastMessage(message); int subId = intent.getExtras().getInt(PhoneConstants.SUBSCRIPTION_KEY); if (SubscriptionManager.isValidSubscriptionId(subId)) { cbm.setSubId(subId); } else { Log.e(TAG, "Invalid subscription id"); } if (!isMessageEnabledByUser(cbm)) { Log.d(TAG, "ignoring alert of type " + cbm.getServiceCategory() + " by user preference"); return; } // If this is an ETWS message, then we want to include the body message to be a factor for // duplication detection. We found that some Japanese carriers send ETWS messages // with the same serial number, therefore the subsequent messages were all ignored. // In the other hand, US carriers have the requirement that only serial number, location, // and category should be used for duplicate detection. int hashCode = message.isEtwsMessage() ? message.getMessageBody().hashCode() : 0; // If this is an ETWS message, we need to include primary/secondary message information to // be a factor for duplication detection as well. Per 3GPP TS 23.041 section 8.2, // duplicate message detection shall be performed independently for primary and secondary // notifications. boolean isEtwsPrimary = false; if (message.isEtwsMessage()) { SmsCbEtwsInfo etwsInfo = message.getEtwsWarningInfo(); if (etwsInfo != null) { isEtwsPrimary = etwsInfo.isPrimary(); } else { Log.w(TAG, "ETWS info is not available."); } } // Check for duplicate message IDs according to CMAS carrier requirements. Message IDs // are stored in volatile memory. If the maximum of 1024 messages is reached, the // message ID of the oldest message is deleted from the list. MessageServiceCategoryAndScope newCmasId = new MessageServiceCategoryAndScope( message.getServiceCategory(), message.getSerialNumber(), message.getLocation(), hashCode, isEtwsPrimary); Log.d(TAG, "message ID = " + newCmasId); long nowTime = SystemClock.elapsedRealtime(); // Check if the identical message arrives again if (sMessagesMap.get(newCmasId) != null) { // And if the previous one has not expired yet, treat it as a duplicate message. long previousTime = sMessagesMap.get(newCmasId); long expirationTime = getDuplicateExpirationTime(subId); if (nowTime - previousTime < expirationTime) { Log.d(TAG, "ignoring the duplicate alert " + newCmasId + ", nowTime=" + nowTime + ", previous=" + previousTime + ", expiration=" + expirationTime); return; } // otherwise, we don't treat it as a duplicate and will show the same message again. Log.d(TAG, "The same message shown up " + (nowTime - previousTime) + " milliseconds ago. Not a duplicate."); } else if (sMessagesMap.size() >= MAX_MESSAGE_ID_SIZE){ // If we reach the maximum, remove the first inserted message key. MessageServiceCategoryAndScope oldestCmasId = sMessagesMap.keySet().iterator().next(); Log.d(TAG, "message ID limit reached, removing oldest message ID " + oldestCmasId); sMessagesMap.remove(oldestCmasId); } else { Log.d(TAG, "New message. Not a duplicate. Map size = " + sMessagesMap.size()); } sMessagesMap.put(newCmasId, nowTime); final Intent alertIntent = new Intent(SHOW_NEW_ALERT_ACTION); alertIntent.setClass(this, CellBroadcastAlertService.class); alertIntent.putExtra("message", cbm); // write to database on a background thread new CellBroadcastContentProvider.AsyncCellBroadcastTask(getContentResolver()) .execute(new CellBroadcastContentProvider.CellBroadcastOperation() { @Override public boolean execute(CellBroadcastContentProvider provider) { if (provider.insertNewBroadcast(cbm)) { // new message, show the alert or notification on UI thread startService(alertIntent); return true; } else { return false; } } }); } private void showNewAlert(Intent intent) { Bundle extras = intent.getExtras(); if (extras == null) { Log.e(TAG, "received SHOW_NEW_ALERT_ACTION with no extras!"); return; } CellBroadcastMessage cbm = (CellBroadcastMessage) intent.getParcelableExtra("message"); if (cbm == null) { Log.e(TAG, "received SHOW_NEW_ALERT_ACTION with no message extra"); return; } if (isEmergencyMessage(this, cbm)) { // start alert sound / vibration / TTS and display full-screen alert openEmergencyAlertNotification(cbm); } else { // add notification to the bar by passing the list of unread non-emergency // CellBroadcastMessages ArrayList messageList = CellBroadcastReceiverApp .addNewMessageToList(cbm); addToNotificationBar(cbm, messageList, this, false); } } /** * Filter out broadcasts on the test channels that the user has not enabled, * and types of notifications that the user is not interested in receiving. * This allows us to enable an entire range of message identifiers in the * radio and not have to explicitly disable the message identifiers for * test broadcasts. In the unlikely event that the default shared preference * values were not initialized in CellBroadcastReceiverApp, the second parameter * to the getBoolean() calls match the default values in res/xml/preferences.xml. * * @param message the message to check * @return true if the user has enabled this message type; false otherwise */ private boolean isMessageEnabledByUser(CellBroadcastMessage message) { // Check if all emergency alerts are disabled. boolean emergencyAlertEnabled = PreferenceManager.getDefaultSharedPreferences(this). getBoolean(CellBroadcastSettings.KEY_ENABLE_EMERGENCY_ALERTS, true); // Check if ETWS/CMAS test message is forced to disabled on the device. boolean forceDisableEtwsCmasTest = CellBroadcastSettings.isFeatureEnabled(this, CarrierConfigManager.KEY_CARRIER_FORCE_DISABLE_ETWS_CMAS_TEST_BOOL, false); if (message.isEtwsTestMessage()) { return emergencyAlertEnabled && !forceDisableEtwsCmasTest && PreferenceManager.getDefaultSharedPreferences(this) .getBoolean(CellBroadcastSettings.KEY_ENABLE_ETWS_TEST_ALERTS, false); } if (message.isEtwsMessage()) { // ETWS messages. // Turn on/off emergency notifications is the only way to turn on/off ETWS messages. return emergencyAlertEnabled; } if (message.isCmasMessage()) { switch (message.getCmasMessageClass()) { case SmsCbCmasInfo.CMAS_CLASS_EXTREME_THREAT: return emergencyAlertEnabled && PreferenceManager.getDefaultSharedPreferences(this).getBoolean( CellBroadcastSettings.KEY_ENABLE_CMAS_EXTREME_THREAT_ALERTS, true); case SmsCbCmasInfo.CMAS_CLASS_SEVERE_THREAT: return emergencyAlertEnabled && PreferenceManager.getDefaultSharedPreferences(this).getBoolean( CellBroadcastSettings.KEY_ENABLE_CMAS_SEVERE_THREAT_ALERTS, true); case SmsCbCmasInfo.CMAS_CLASS_CHILD_ABDUCTION_EMERGENCY: return emergencyAlertEnabled && PreferenceManager.getDefaultSharedPreferences(this) .getBoolean(CellBroadcastSettings.KEY_ENABLE_CMAS_AMBER_ALERTS, true); case SmsCbCmasInfo.CMAS_CLASS_REQUIRED_MONTHLY_TEST: case SmsCbCmasInfo.CMAS_CLASS_CMAS_EXERCISE: case SmsCbCmasInfo.CMAS_CLASS_OPERATOR_DEFINED_USE: return emergencyAlertEnabled && !forceDisableEtwsCmasTest && PreferenceManager.getDefaultSharedPreferences(this) .getBoolean(CellBroadcastSettings.KEY_ENABLE_CMAS_TEST_ALERTS, false); default: return true; // presidential-level CMAS alerts are always enabled } } if (message.getServiceCategory() == 50) { // save latest area info broadcast for Settings display and send as broadcast CellBroadcastReceiverApp.setLatestAreaInfo(message); Intent intent = new Intent(CB_AREA_INFO_RECEIVED_ACTION); intent.putExtra("message", message); // Send broadcast twice, once for apps that have PRIVILEGED permission and once // for those that have the runtime one sendBroadcastAsUser(intent, UserHandle.ALL, android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE); sendBroadcastAsUser(intent, UserHandle.ALL, android.Manifest.permission.READ_PHONE_STATE); return false; // area info broadcasts are displayed in Settings status screen } return true; // other broadcast messages are always enabled } /** * Display a full-screen alert message for emergency alerts. * @param message the alert to display */ private void openEmergencyAlertNotification(CellBroadcastMessage message) { // Acquire a CPU wake lock until the alert dialog and audio start playing. CellBroadcastAlertWakeLock.acquireScreenCpuWakeLock(this); // Close dialogs and window shade Intent closeDialogs = new Intent(Intent.ACTION_CLOSE_SYSTEM_DIALOGS); sendBroadcast(closeDialogs); // start audio/vibration/speech service for emergency alerts Intent audioIntent = new Intent(this, CellBroadcastAlertAudio.class); audioIntent.setAction(CellBroadcastAlertAudio.ACTION_START_ALERT_AUDIO); SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this); ToneType toneType = ToneType.CMAS_DEFAULT; if (message.isEtwsMessage()) { // For ETWS, always vibrate, even in silent mode. audioIntent.putExtra(CellBroadcastAlertAudio.ALERT_AUDIO_VIBRATE_EXTRA, true); audioIntent.putExtra(CellBroadcastAlertAudio.ALERT_AUDIO_ETWS_VIBRATE_EXTRA, true); toneType = ToneType.ETWS_DEFAULT; if (message.getEtwsWarningInfo() != null) { int warningType = message.getEtwsWarningInfo().getWarningType(); switch (warningType) { case SmsCbEtwsInfo.ETWS_WARNING_TYPE_EARTHQUAKE: case SmsCbEtwsInfo.ETWS_WARNING_TYPE_EARTHQUAKE_AND_TSUNAMI: toneType = ToneType.EARTHQUAKE; break; case SmsCbEtwsInfo.ETWS_WARNING_TYPE_TSUNAMI: toneType = ToneType.TSUNAMI; break; case SmsCbEtwsInfo.ETWS_WARNING_TYPE_OTHER_EMERGENCY: toneType = ToneType.OTHER; break; } } } else { // For other alerts, vibration can be disabled in app settings. audioIntent.putExtra(CellBroadcastAlertAudio.ALERT_AUDIO_VIBRATE_EXTRA, prefs.getBoolean(CellBroadcastSettings.KEY_ENABLE_ALERT_VIBRATE, true)); int channel = message.getServiceCategory(); ArrayList ranges= CellBroadcastOtherChannelsManager. getInstance().getCellBroadcastChannelRanges(getApplicationContext(), message.getSubId()); if (ranges != null) { for (CellBroadcastChannelRange range : ranges) { if (channel >= range.mStartId && channel <= range.mEndId) { toneType = range.mToneType; break; } } } } audioIntent.putExtra(CellBroadcastAlertAudio.ALERT_AUDIO_TONE_TYPE, toneType); String messageBody = message.getMessageBody(); if (prefs.getBoolean(CellBroadcastSettings.KEY_ENABLE_ALERT_SPEECH, true)) { audioIntent.putExtra(CellBroadcastAlertAudio.ALERT_AUDIO_MESSAGE_BODY, messageBody); String preferredLanguage = message.getLanguageCode(); String defaultLanguage = null; if (message.isEtwsMessage()) { // Only do TTS for ETWS secondary message. // There is no text in ETWS primary message. When we construct the ETWS primary // message, we hardcode "ETWS" as the body hence we don't want to speak that out // here. // Also in many cases we see the secondary message comes few milliseconds after // the primary one. If we play TTS for the primary one, It will be overwritten by // the secondary one immediately anyway. if (!message.getEtwsWarningInfo().isPrimary()) { // Since only Japanese carriers are using ETWS, if there is no language // specified in the ETWS message, we'll use Japanese as the default language. defaultLanguage = "ja"; } } else { // If there is no language specified in the CMAS message, use device's // default language. defaultLanguage = Locale.getDefault().getLanguage(); } Log.d(TAG, "Preferred language = " + preferredLanguage + ", Default language = " + defaultLanguage); audioIntent.putExtra(CellBroadcastAlertAudio.ALERT_AUDIO_MESSAGE_PREFERRED_LANGUAGE, preferredLanguage); audioIntent.putExtra(CellBroadcastAlertAudio.ALERT_AUDIO_MESSAGE_DEFAULT_LANGUAGE, defaultLanguage); } startService(audioIntent); ArrayList messageList = new ArrayList(1); messageList.add(message); Intent alertDialogIntent = createDisplayMessageIntent(this, CellBroadcastAlertDialog.class, messageList); alertDialogIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); startActivity(alertDialogIntent); } /** * Add the new alert to the notification bar (non-emergency alerts), or launch a * high-priority immediate intent for emergency alerts. * @param message the alert to display */ static void addToNotificationBar(CellBroadcastMessage message, ArrayList messageList, Context context, boolean fromSaveState) { int channelTitleId = CellBroadcastResources.getDialogTitleResource(context, message); CharSequence channelName = context.getText(channelTitleId); String messageBody = message.getMessageBody(); // Create intent to show the new messages when user selects the notification. Intent intent = createDisplayMessageIntent(context, CellBroadcastAlertDialog.class, messageList); intent.putExtra(CellBroadcastAlertDialog.FROM_NOTIFICATION_EXTRA, true); intent.putExtra(CellBroadcastAlertDialog.FROM_SAVE_STATE_NOTIFICATION_EXTRA, fromSaveState); PendingIntent pi = PendingIntent.getActivity(context, NOTIFICATION_ID, intent, PendingIntent.FLAG_ONE_SHOT | PendingIntent.FLAG_UPDATE_CURRENT); // use default sound/vibration/lights for non-emergency broadcasts Notification.Builder builder = new Notification.Builder(context) .setSmallIcon(R.drawable.ic_notify_alert) .setTicker(channelName) .setWhen(System.currentTimeMillis()) .setContentIntent(pi) .setCategory(Notification.CATEGORY_SYSTEM) .setPriority(Notification.PRIORITY_HIGH) .setColor(context.getResources().getColor(R.color.notification_color)) .setVisibility(Notification.VISIBILITY_PUBLIC) .setDefaults(Notification.DEFAULT_ALL); builder.setDefaults(Notification.DEFAULT_ALL); // increment unread alert count (decremented when user dismisses alert dialog) int unreadCount = messageList.size(); if (unreadCount > 1) { // use generic count of unread broadcasts if more than one unread builder.setContentTitle(context.getString(R.string.notification_multiple_title)); builder.setContentText(context.getString(R.string.notification_multiple, unreadCount)); } else { builder.setContentTitle(channelName).setContentText(messageBody); } NotificationManager notificationManager = NotificationManager.from(context); notificationManager.notify(NOTIFICATION_ID, builder.build()); } static Intent createDisplayMessageIntent(Context context, Class intentClass, ArrayList messageList) { // Trigger the list activity to fire up a dialog that shows the received messages Intent intent = new Intent(context, intentClass); intent.putParcelableArrayListExtra(CellBroadcastMessage.SMS_CB_MESSAGE_EXTRA, messageList); return intent; } @VisibleForTesting @Override public IBinder onBind(Intent intent) { return new LocalBinder(); } @VisibleForTesting class LocalBinder extends Binder { public CellBroadcastAlertService getService() { return CellBroadcastAlertService.this; } } /** * Check if the cell broadcast message is an emergency message or not * @param context Device context * @param cbm Cell broadcast message * @return True if the message is an emergency message, otherwise false. */ public static boolean isEmergencyMessage(Context context, CellBroadcastMessage cbm) { boolean isEmergency = false; if (cbm == null) { return false; } int id = cbm.getServiceCategory(); int subId = cbm.getSubId(); if (cbm.isEmergencyAlertMessage()) { isEmergency = true; } else { ArrayList ranges = CellBroadcastOtherChannelsManager. getInstance().getCellBroadcastChannelRanges(context, subId); if (ranges != null) { for (CellBroadcastChannelRange range : ranges) { if (range.mStartId <= id && range.mEndId >= id) { isEmergency = range.mIsEmergency; break; } } } } Log.d(TAG, "isEmergencyMessage: " + isEmergency + ", subId = " + subId + ", " + "message id = " + id); return isEmergency; } }