DO NOT MERGE Suppress notifications when device enter lockdown

This CL makes the following modifcations:
1. Add LockPatternUtils.StrongAuthTracker to monitor
the lockdown mode status of the phone.
2. Call mListeners.notifyRemovedLocked with all the
notifications in the mNotificationList when entering
the lockdown mode.
3. Call mListeners.notifyPostedLocked with all the
notifications in the mNotificationList when exiting
the lockdown mode.
4. Dismiss the function calls of notifyPostedLocked,
notifyRemovedLocked, and notifyRankingUpdateLocked
during the lockdown mode.

The CL also adds corresponding tests.

Bug: 173721373
Test: atest NotificationManagerServiceTest
Test: atest NotificationListenersTest
Test: manually verify the paired device cannot receive
notifications when the host phone is in lockdown mode.
Ignore-AOSP-First: pending fix for a security issue.

Change-Id: I7e83544863eeadf8272b6ff8a9bb8136d6466203
Merged-In: I7e83544863eeadf8272b6ff8a9bb8136d6466203
(cherry picked from commit 3cb6842a053e236cc98d7616ba4433c31ffda3ac)
diff --git a/services/core/java/com/android/server/notification/NotificationManagerService.java b/services/core/java/com/android/server/notification/NotificationManagerService.java
index 0309ddf..0c11d8f 100755
--- a/services/core/java/com/android/server/notification/NotificationManagerService.java
+++ b/services/core/java/com/android/server/notification/NotificationManagerService.java
@@ -252,6 +252,7 @@
 import android.util.Pair;
 import android.util.Slog;
 import android.util.SparseArray;
+import android.util.SparseBooleanArray;
 import android.util.StatsEvent;
 import android.util.TypedXmlPullParser;
 import android.util.TypedXmlSerializer;
@@ -284,6 +285,7 @@
 import com.android.internal.util.Preconditions;
 import com.android.internal.util.XmlUtils;
 import com.android.internal.util.function.TriPredicate;
+import com.android.internal.widget.LockPatternUtils;
 import com.android.server.DeviceIdleInternal;
 import com.android.server.EventLogTags;
 import com.android.server.IoThread;
@@ -1923,6 +1925,54 @@
     private SettingsObserver mSettingsObserver;
     protected ZenModeHelper mZenModeHelper;
 
+    protected class StrongAuthTracker extends LockPatternUtils.StrongAuthTracker {
+
+        SparseBooleanArray mUserInLockDownMode = new SparseBooleanArray();
+        boolean mIsInLockDownMode = false;
+
+        StrongAuthTracker(Context context) {
+            super(context);
+        }
+
+        private boolean containsFlag(int haystack, int needle) {
+            return (haystack & needle) != 0;
+        }
+
+        public boolean isInLockDownMode() {
+            return mIsInLockDownMode;
+        }
+
+        @Override
+        public synchronized void onStrongAuthRequiredChanged(int userId) {
+            boolean userInLockDownModeNext = containsFlag(getStrongAuthForUser(userId),
+                    STRONG_AUTH_REQUIRED_AFTER_USER_LOCKDOWN);
+            mUserInLockDownMode.put(userId, userInLockDownModeNext);
+            boolean isInLockDownModeNext = mUserInLockDownMode.indexOfValue(true) != -1;
+
+            if (mIsInLockDownMode == isInLockDownModeNext) {
+                return;
+            }
+
+            if (isInLockDownModeNext) {
+                cancelNotificationsWhenEnterLockDownMode();
+            }
+
+            // When the mIsInLockDownMode is true, both notifyPostedLocked and
+            // notifyRemovedLocked will be dismissed. So we shall call
+            // cancelNotificationsWhenEnterLockDownMode before we set mIsInLockDownMode
+            // as true and call postNotificationsWhenExitLockDownMode after we set
+            // mIsInLockDownMode as false.
+            mIsInLockDownMode = isInLockDownModeNext;
+
+            if (!isInLockDownModeNext) {
+                postNotificationsWhenExitLockDownMode();
+            }
+        }
+    }
+
+    private LockPatternUtils mLockPatternUtils;
+    private StrongAuthTracker mStrongAuthTracker;
+
     public NotificationManagerService(Context context) {
         this(context,
                 new NotificationRecordLoggerImpl(),
@@ -1952,6 +2002,11 @@
     }
 
     @VisibleForTesting
+    void setStrongAuthTracker(StrongAuthTracker strongAuthTracker) {
+        mStrongAuthTracker = strongAuthTracker;
+    }
+
+    @VisibleForTesting
     void setKeyguardManager(KeyguardManager keyguardManager) {
         mKeyguardManager = keyguardManager;
     }
@@ -2145,6 +2200,8 @@
         mPlatformCompat = IPlatformCompat.Stub.asInterface(
                 ServiceManager.getService(Context.PLATFORM_COMPAT_SERVICE));
 
+        mLockPatternUtils = new LockPatternUtils(getContext());
+        mStrongAuthTracker = new StrongAuthTracker(getContext());
         mUiHandler = new Handler(UiThread.get().getLooper());
         String[] extractorNames;
         try {
@@ -2641,6 +2698,7 @@
                 bubbsExtractor.setShortcutHelper(mShortcutHelper);
             }
             registerNotificationPreferencesPullers();
+            mLockPatternUtils.registerStrongAuthTracker(mStrongAuthTracker);
         } else if (phase == SystemService.PHASE_THIRD_PARTY_APPS_CAN_START) {
             // This observer will force an update when observe is called, causing us to
             // bind to listener services.
@@ -9537,6 +9595,29 @@
         }
     }
 
+    private void cancelNotificationsWhenEnterLockDownMode() {
+        synchronized (mNotificationLock) {
+            int numNotifications = mNotificationList.size();
+            for (int i = 0; i < numNotifications; i++) {
+                NotificationRecord rec = mNotificationList.get(i);
+                mListeners.notifyRemovedLocked(rec, REASON_CANCEL_ALL,
+                        rec.getStats());
+            }
+
+        }
+    }
+
+    private void postNotificationsWhenExitLockDownMode() {
+        synchronized (mNotificationLock) {
+            int numNotifications = mNotificationList.size();
+            for (int i = 0; i < numNotifications; i++) {
+                NotificationRecord rec = mNotificationList.get(i);
+                mListeners.notifyPostedLocked(rec, rec);
+            }
+
+        }
+    }
+
     private void updateNotificationPulse() {
         synchronized (mNotificationLock) {
             updateLightsLocked();
@@ -9753,6 +9834,10 @@
                 rankings.toArray(new NotificationListenerService.Ranking[0]));
     }
 
+    boolean isInLockDownMode() {
+        return mStrongAuthTracker.isInLockDownMode();
+    }
+
     boolean hasCompanionDevice(ManagedServiceInfo info) {
         if (mCompanionManager == null) {
             mCompanionManager = getCompanionManager();
@@ -10804,8 +10889,12 @@
          *                           targetting <= O_MR1
          */
         @GuardedBy("mNotificationLock")
-        private void notifyPostedLocked(NotificationRecord r, NotificationRecord old,
+        void notifyPostedLocked(NotificationRecord r, NotificationRecord old,
                 boolean notifyAllListeners) {
+            if (isInLockDownMode()) {
+                return;
+            }
+
             try {
                 // Lazily initialized snapshots of the notification.
                 StatusBarNotification sbn = r.getSbn();
@@ -10908,6 +10997,10 @@
         @GuardedBy("mNotificationLock")
         public void notifyRemovedLocked(NotificationRecord r, int reason,
                 NotificationStats notificationStats) {
+            if (isInLockDownMode()) {
+                return;
+            }
+
             final StatusBarNotification sbn = r.getSbn();
 
             // make a copy in case changes are made to the underlying Notification object
@@ -10953,6 +11046,10 @@
          */
         @GuardedBy("mNotificationLock")
         public void notifyRankingUpdateLocked(List<NotificationRecord> changedHiddenNotifications) {
+            if (isInLockDownMode()) {
+                return;
+            }
+
             boolean isHiddenRankingUpdate = changedHiddenNotifications != null
                     && changedHiddenNotifications.size() > 0;
             // TODO (b/73052211): if the ranking update changed the notification type,
diff --git a/services/tests/uiservicestests/AndroidManifest.xml b/services/tests/uiservicestests/AndroidManifest.xml
index 767857b..e8e3a8f 100644
--- a/services/tests/uiservicestests/AndroidManifest.xml
+++ b/services/tests/uiservicestests/AndroidManifest.xml
@@ -33,6 +33,7 @@
     <uses-permission android:name="android.permission.OBSERVE_ROLE_HOLDERS" />
     <uses-permission android:name="android.permission.GET_INTENT_SENDER_INTENT"/>
     <uses-permission android:name="android.permission.WRITE_DEVICE_CONFIG" />
+    <uses-permission android:name="android.permission.ACCESS_KEYGUARD_SECURE_STORAGE" />
 
     <application android:debuggable="true">
         <uses-library android:name="android.test.runner" />
diff --git a/services/tests/uiservicestests/src/com/android/server/notification/NotificationListenersTest.java b/services/tests/uiservicestests/src/com/android/server/notification/NotificationListenersTest.java
index 4a13050..c5131c8 100644
--- a/services/tests/uiservicestests/src/com/android/server/notification/NotificationListenersTest.java
+++ b/services/tests/uiservicestests/src/com/android/server/notification/NotificationListenersTest.java
@@ -31,8 +31,11 @@
 import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.ArgumentMatchers.nullable;
+import static org.mockito.Mockito.atLeast;
 import static org.mockito.Mockito.doNothing;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.reset;
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
@@ -42,18 +45,16 @@
 import android.app.NotificationChannel;
 import android.app.NotificationManager;
 import android.content.ComponentName;
-import android.content.Context;
 import android.content.pm.IPackageManager;
 import android.content.pm.PackageManager;
 import android.content.pm.ServiceInfo;
 import android.content.pm.VersionedPackage;
 import android.os.Bundle;
-import android.os.IBinder;
-import android.os.IInterface;
 import android.os.UserHandle;
 import android.service.notification.NotificationListenerFilter;
 import android.service.notification.NotificationListenerService;
 import android.service.notification.NotificationRankingUpdate;
+import android.service.notification.NotificationStats;
 import android.service.notification.StatusBarNotification;
 import android.testing.TestableContext;
 import android.util.ArraySet;
@@ -70,6 +71,7 @@
 import org.junit.Test;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
+import org.mockito.internal.util.reflection.FieldSetter;
 
 import java.io.BufferedInputStream;
 import java.io.BufferedOutputStream;
@@ -430,4 +432,66 @@
         verify(mPmi).grantImplicitAccess(sbn.getUserId(), null, UserHandle.getAppId(33),
                 sbn.getUid(), false, false);
     }
+
+    @Test
+    public void testNotifyPostedLockedInLockdownMode() {
+        NotificationRecord r = mock(NotificationRecord.class);
+        NotificationRecord old = mock(NotificationRecord.class);
+
+        // before the lockdown mode
+        when(mNm.isInLockDownMode()).thenReturn(false);
+        mListeners.notifyPostedLocked(r, old, true);
+        mListeners.notifyPostedLocked(r, old, false);
+        verify(r, atLeast(2)).getSbn();
+
+        // in the lockdown mode
+        reset(r);
+        reset(old);
+        when(mNm.isInLockDownMode()).thenReturn(true);
+        mListeners.notifyPostedLocked(r, old, true);
+        mListeners.notifyPostedLocked(r, old, false);
+        verify(r, never()).getSbn();
+    }
+
+    @Test
+    public void testnotifyRankingUpdateLockedInLockdownMode() {
+        List chn = mock(List.class);
+
+        // before the lockdown mode
+        when(mNm.isInLockDownMode()).thenReturn(false);
+        mListeners.notifyRankingUpdateLocked(chn);
+        verify(chn, atLeast(1)).size();
+
+        // in the lockdown mode
+        reset(chn);
+        when(mNm.isInLockDownMode()).thenReturn(true);
+        mListeners.notifyRankingUpdateLocked(chn);
+        verify(chn, never()).size();
+    }
+
+    @Test
+    public void testNotifyRemovedLockedInLockdownMode() throws NoSuchFieldException {
+        NotificationRecord r = mock(NotificationRecord.class);
+        NotificationStats rs = mock(NotificationStats.class);
+        StatusBarNotification sbn = mock(StatusBarNotification.class);
+        FieldSetter.setField(mNm,
+                NotificationManagerService.class.getDeclaredField("mHandler"),
+                mock(NotificationManagerService.WorkerHandler.class));
+
+        // before the lockdown mode
+        when(mNm.isInLockDownMode()).thenReturn(false);
+        when(r.getSbn()).thenReturn(sbn);
+        mListeners.notifyRemovedLocked(r, 0, rs);
+        mListeners.notifyRemovedLocked(r, 0, rs);
+        verify(r, atLeast(2)).getSbn();
+
+        // in the lockdown mode
+        reset(r);
+        reset(rs);
+        when(mNm.isInLockDownMode()).thenReturn(true);
+        when(r.getSbn()).thenReturn(sbn);
+        mListeners.notifyRemovedLocked(r, 0, rs);
+        mListeners.notifyRemovedLocked(r, 0, rs);
+        verify(r, never()).getSbn();
+    }
 }
diff --git a/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java b/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
index b987c69..348e015 100755
--- a/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
+++ b/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
@@ -63,10 +63,13 @@
 import static android.service.notification.NotificationListenerService.FLAG_FILTER_TYPE_ALERTING;
 import static android.service.notification.NotificationListenerService.FLAG_FILTER_TYPE_CONVERSATIONS;
 import static android.service.notification.NotificationListenerService.FLAG_FILTER_TYPE_ONGOING;
+import static android.service.notification.NotificationListenerService.REASON_CANCEL_ALL;
 import static android.service.notification.NotificationListenerService.Ranking.USER_SENTIMENT_NEGATIVE;
 import static android.service.notification.NotificationListenerService.Ranking.USER_SENTIMENT_NEUTRAL;
 import static android.view.WindowManager.LayoutParams.TYPE_TOAST;
 
+import static com.android.internal.widget.LockPatternUtils.StrongAuthTracker.STRONG_AUTH_REQUIRED_AFTER_USER_LOCKDOWN;
+
 import static com.google.common.truth.Truth.assertThat;
 
 import static junit.framework.Assert.assertEquals;
@@ -352,6 +355,7 @@
     MultiRateLimiter mToastRateLimiter;
     BroadcastReceiver mPackageIntentReceiver;
     NotificationRecordLoggerFake mNotificationRecordLogger = new NotificationRecordLoggerFake();
+    TestableNotificationManagerService.StrongAuthTrackerFake mStrongAuthTracker;
     private InstanceIdSequence mNotificationInstanceIdSequence = new InstanceIdSequenceFake(
             1 << 30);
     @Mock
@@ -508,6 +512,9 @@
 
         mService.setAudioManager(mAudioManager);
 
+        mStrongAuthTracker = mService.new StrongAuthTrackerFake(mContext);
+        mService.setStrongAuthTracker(mStrongAuthTracker);
+
         mShortcutHelper = mService.getShortcutHelper();
         mShortcutHelper.setLauncherApps(mLauncherApps);
         mShortcutHelper.setShortcutServiceInternal(mShortcutServiceInternal);
@@ -9247,4 +9254,44 @@
         // make sure the summary was removed and not re-posted
         assertThat(mService.getNotificationRecordCount()).isEqualTo(0);
     }
+
+    @Test
+    public void testStrongAuthTracker_isInLockDownMode() {
+        mStrongAuthTracker.setGetStrongAuthForUserReturnValue(
+                STRONG_AUTH_REQUIRED_AFTER_USER_LOCKDOWN);
+        mStrongAuthTracker.onStrongAuthRequiredChanged(mContext.getUserId());
+        assertTrue(mStrongAuthTracker.isInLockDownMode());
+        mStrongAuthTracker.setGetStrongAuthForUserReturnValue(0);
+        mStrongAuthTracker.onStrongAuthRequiredChanged(mContext.getUserId());
+        assertFalse(mStrongAuthTracker.isInLockDownMode());
+    }
+
+    @Test
+    public void testCancelAndPostNotificationsWhenEnterAndExitLockDownMode() {
+        // post 2 notifications from 2 packages
+        NotificationRecord pkgA = new NotificationRecord(mContext,
+                generateSbn("a", 1000, 9, 0), mTestNotificationChannel);
+        mService.addNotification(pkgA);
+        NotificationRecord pkgB = new NotificationRecord(mContext,
+                generateSbn("b", 1001, 9, 0), mTestNotificationChannel);
+        mService.addNotification(pkgB);
+
+        // when entering the lockdown mode, cancel the 2 notifications.
+        mStrongAuthTracker.setGetStrongAuthForUserReturnValue(
+                STRONG_AUTH_REQUIRED_AFTER_USER_LOCKDOWN);
+        mStrongAuthTracker.onStrongAuthRequiredChanged(mContext.getUserId());
+        assertTrue(mStrongAuthTracker.isInLockDownMode());
+
+        // the notifyRemovedLocked function is called twice due to REASON_CANCEL_ALL.
+        ArgumentCaptor<Integer> captor = ArgumentCaptor.forClass(Integer.class);
+        verify(mListeners, times(2)).notifyRemovedLocked(any(), captor.capture(), any());
+        assertEquals(REASON_CANCEL_ALL, captor.getValue().intValue());
+
+        // exit lockdown mode.
+        mStrongAuthTracker.setGetStrongAuthForUserReturnValue(0);
+        mStrongAuthTracker.onStrongAuthRequiredChanged(mContext.getUserId());
+
+        // the notifyPostedLocked function is called twice.
+        verify(mListeners, times(2)).notifyPostedLocked(any(), any());
+    }
 }
diff --git a/services/tests/uiservicestests/src/com/android/server/notification/TestableNotificationManagerService.java b/services/tests/uiservicestests/src/com/android/server/notification/TestableNotificationManagerService.java
index bde0485..4ed7d35 100644
--- a/services/tests/uiservicestests/src/com/android/server/notification/TestableNotificationManagerService.java
+++ b/services/tests/uiservicestests/src/com/android/server/notification/TestableNotificationManagerService.java
@@ -113,4 +113,20 @@
     protected void doChannelWarningToast(int uid, CharSequence toastText) {
         mChannelToastsSent.add(uid);
     }
+
+    public class StrongAuthTrackerFake extends NotificationManagerService.StrongAuthTracker {
+        private int mGetStrongAuthForUserReturnValue = 0;
+        StrongAuthTrackerFake(Context context) {
+            super(context);
+        }
+
+        public void setGetStrongAuthForUserReturnValue(int val) {
+            mGetStrongAuthForUserReturnValue = val;
+        }
+
+        @Override
+        public int getStrongAuthForUser(int userId) {
+            return mGetStrongAuthForUserReturnValue;
+        }
+    }
 }