From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Wenhao Wang <wenhaowang@google.com>
Date: Tue, 30 Aug 2022 11:09:46 -0700
Subject: [PATCH] Enable user graularity for lockdown mode
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The NotificationManagerService registers a LockPatternUtils.StrongAuthTracker
to observe the StrongAuth changes of every user.
More specifically, it’s the STRONG_AUTH_REQUIRED_AFTER_USER_LOCKDOWN flag.
Via this flag, NotificationManagerService can perform the following operations
when the user enter or exit lockdown mode:

Enter lockdown:
1. Remove all the notifications belonging to the user.
2. Set the local flag to indicate the lockdown is on for the user.
   The local flag will suppress the user's notifications on the
   post, remove and update functions.

Exit lockdown:
1. Clear the local flag to indicate the lockdown is off for the user.
2. Repost the user’s notifications (suppressed during lockdown mode).

The CL also updates corresponding tests.

Bug: 173721373
Bug: 250743174
Test: atest NotificationManagerServiceTest
Test: atest NotificationListenersTest
Ignore-AOSP-First: pending fix for a security issue.

Change-Id: I4f30e56550729db7d673a92d2a1250509713f36d
Merged-In: I4f30e56550729db7d673a92d2a1250509713f36d
(cherry picked from commit de3b12fca23178d8c821058261572449b67d5967)
(cherry picked from commit 5e40f39f5bd4ae769d79ce022a64f1345512b65d)
Merged-In: I4f30e56550729db7d673a92d2a1250509713f36d
---
 .../NotificationManagerService.java           |  75 ++++++----
 .../NotificationListenersTest.java            | 136 ++++++++++++------
 .../NotificationManagerServiceTest.java       |  64 ++++++++-
 3 files changed, 197 insertions(+), 78 deletions(-)

diff --git a/services/core/java/com/android/server/notification/NotificationManagerService.java b/services/core/java/com/android/server/notification/NotificationManagerService.java
index c9831781b543..7ae80d927aaa 100755
--- a/services/core/java/com/android/server/notification/NotificationManagerService.java
+++ b/services/core/java/com/android/server/notification/NotificationManagerService.java
@@ -1535,34 +1535,39 @@ public class NotificationManagerService extends SystemService {
             return (haystack & needle) != 0;
         }
 
-        public boolean isInLockDownMode() {
-            return mIsInLockDownMode;
+        // Return whether the user is in lockdown mode.
+        // If the flag is not set, we assume the user is not in lockdown.
+        public boolean isInLockDownMode(int userId) {
+            return mUserInLockDownMode.get(userId, false);
         }
 
         @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) {
+            // Nothing happens if the lockdown mode of userId keeps the same.
+            if (userInLockDownModeNext == isInLockDownMode(userId)) {
                 return;
             }
 
-            if (isInLockDownModeNext) {
-                cancelNotificationsWhenEnterLockDownMode();
+            // When the lockdown mode is changed, we perform the following steps.
+            // If the userInLockDownModeNext is true, all the function calls to
+            // notifyPostedLocked and notifyRemovedLocked will not be executed.
+            // The cancelNotificationsWhenEnterLockDownMode calls notifyRemovedLocked
+            // and postNotificationsWhenExitLockDownMode calls notifyPostedLocked.
+            // So we shall call cancelNotificationsWhenEnterLockDownMode before
+            // we set mUserInLockDownMode as true.
+            // On the other hand, if the userInLockDownModeNext is false, we shall call
+            // postNotificationsWhenExitLockDownMode after we put false into mUserInLockDownMode
+            if (userInLockDownModeNext) {
+                cancelNotificationsWhenEnterLockDownMode(userId);
             }
 
-            // 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;
+            mUserInLockDownMode.put(userId, userInLockDownModeNext);
 
-            if (!isInLockDownModeNext) {
-                postNotificationsWhenExitLockDownMode();
+            if (!userInLockDownModeNext) {
+                postNotificationsWhenExitLockDownMode(userId);
             }
         }
     }
@@ -7579,11 +7584,14 @@ public class NotificationManagerService extends SystemService {
         }
     }
 
-    private void cancelNotificationsWhenEnterLockDownMode() {
+    private void cancelNotificationsWhenEnterLockDownMode(int userId) {
         synchronized (mNotificationLock) {
             int numNotifications = mNotificationList.size();
             for (int i = 0; i < numNotifications; i++) {
                 NotificationRecord rec = mNotificationList.get(i);
+                if (rec.getUser().getIdentifier() != userId) {
+                    continue;
+                }
                 mListeners.notifyRemovedLocked(rec, REASON_CANCEL_ALL,
                         rec.getStats());
             }
@@ -7591,14 +7599,23 @@ public class NotificationManagerService extends SystemService {
         }
     }
 
-    private void postNotificationsWhenExitLockDownMode() {
+    private void postNotificationsWhenExitLockDownMode(int userId) {
         synchronized (mNotificationLock) {
             int numNotifications = mNotificationList.size();
+            // Set the delay to spread out the burst of notifications.
+            long delay = 0;
             for (int i = 0; i < numNotifications; i++) {
                 NotificationRecord rec = mNotificationList.get(i);
-                mListeners.notifyPostedLocked(rec, rec);
+                if (rec.getUser().getIdentifier() != userId) {
+                    continue;
+                }
+                mHandler.postDelayed(() -> {
+                    synchronized (mNotificationLock) {
+                        mListeners.notifyPostedLocked(rec, rec);
+                    }
+                }, delay);
+                delay += 20;
             }
-
         }
     }
 
@@ -7777,12 +7794,15 @@ public class NotificationManagerService extends SystemService {
      * notifications visible to the given listener.
      */
     @GuardedBy("mNotificationLock")
-    private NotificationRankingUpdate makeRankingUpdateLocked(ManagedServiceInfo info) {
+    NotificationRankingUpdate makeRankingUpdateLocked(ManagedServiceInfo info) {
         final int N = mNotificationList.size();
         final ArrayList<NotificationListenerService.Ranking> rankings = new ArrayList<>();
 
         for (int i = 0; i < N; i++) {
             NotificationRecord record = mNotificationList.get(i);
+            if (isInLockDownMode(record.getUser().getIdentifier())) {
+                continue;
+            }
             if (!isVisibleToListener(record.sbn, info)) {
                 continue;
             }
@@ -7818,8 +7838,8 @@ public class NotificationManagerService extends SystemService {
                 rankings.toArray(new NotificationListenerService.Ranking[0]));
     }
 
-    boolean isInLockDownMode() {
-        return mStrongAuthTracker.isInLockDownMode();
+    boolean isInLockDownMode(int userId) {
+        return mStrongAuthTracker.isInLockDownMode(userId);
     }
 
     boolean hasCompanionDevice(ManagedServiceInfo info) {
@@ -7854,7 +7874,8 @@ public class NotificationManagerService extends SystemService {
                 ServiceManager.getService(Context.COMPANION_DEVICE_SERVICE));
     }
 
-    private boolean isVisibleToListener(StatusBarNotification sbn, ManagedServiceInfo listener) {
+    @VisibleForTesting
+    boolean isVisibleToListener(StatusBarNotification sbn, ManagedServiceInfo listener) {
         if (!listener.enabledAndUserMatches(sbn.getUserId())) {
             return false;
         }
@@ -8454,7 +8475,7 @@ public class NotificationManagerService extends SystemService {
         @GuardedBy("mNotificationLock")
         void notifyPostedLocked(NotificationRecord r, NotificationRecord old,
                 boolean notifyAllListeners) {
-            if (isInLockDownMode()) {
+            if (isInLockDownMode(r.getUser().getIdentifier())) {
                 return;
             }
 
@@ -8520,7 +8541,7 @@ public class NotificationManagerService extends SystemService {
         @GuardedBy("mNotificationLock")
         public void notifyRemovedLocked(NotificationRecord r, int reason,
                 NotificationStats notificationStats) {
-            if (isInLockDownMode()) {
+            if (isInLockDownMode(r.getUser().getIdentifier())) {
                 return;
             }
 
@@ -8575,10 +8596,6 @@ public class NotificationManagerService extends SystemService {
          */
         @GuardedBy("mNotificationLock")
         public void notifyRankingUpdateLocked(List<NotificationRecord> changedHiddenNotifications) {
-            if (isInLockDownMode()) {
-                return;
-            }
-
             boolean isHiddenRankingUpdate = changedHiddenNotifications != null
                     && changedHiddenNotifications.size() > 0;
 
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 793739bfe8f5..66bacbbe7ed1 100644
--- a/services/tests/uiservicestests/src/com/android/server/notification/NotificationListenersTest.java
+++ b/services/tests/uiservicestests/src/com/android/server/notification/NotificationListenersTest.java
@@ -28,6 +28,7 @@ import static org.mockito.Mockito.when;
 import android.app.INotificationManager;
 import android.content.pm.IPackageManager;
 import android.content.pm.PackageManager;
+import android.os.UserHandle;
 import android.service.notification.NotificationStats;
 import android.service.notification.StatusBarNotification;
 import android.testing.TestableContext;
@@ -40,8 +41,6 @@ import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 import org.mockito.internal.util.reflection.FieldSetter;
 
-import java.util.List;
-
 public class NotificationListenersTest extends UiServiceTestCase {
 
     @Mock
@@ -70,66 +69,117 @@ public class NotificationListenersTest extends UiServiceTestCase {
 
     @Test
     public void testNotifyPostedLockedInLockdownMode() {
-        NotificationRecord r = mock(NotificationRecord.class);
-        NotificationRecord old = mock(NotificationRecord.class);
+        NotificationRecord r0 = mock(NotificationRecord.class);
+        NotificationRecord old0 = mock(NotificationRecord.class);
+        UserHandle uh0 = mock(UserHandle.class);
+
+        NotificationRecord r1 = mock(NotificationRecord.class);
+        NotificationRecord old1 = mock(NotificationRecord.class);
+        UserHandle uh1 = mock(UserHandle.class);
+
+        // Neither user0 and user1 is in the lockdown mode
+        when(r0.getUser()).thenReturn(uh0);
+        when(uh0.getIdentifier()).thenReturn(0);
+        when(mNm.isInLockDownMode(0)).thenReturn(false);
+
+        when(r1.getUser()).thenReturn(uh1);
+        when(uh1.getIdentifier()).thenReturn(1);
+        when(mNm.isInLockDownMode(1)).thenReturn(false);
+
+        mListeners.notifyPostedLocked(r0, old0, true);
+        mListeners.notifyPostedLocked(r0, old0, false);
+        verify(mListeners, times(2)).getServices();
 
-        // before the lockdown mode
-        when(mNm.isInLockDownMode()).thenReturn(false);
-        mListeners.notifyPostedLocked(r, old, true);
-        mListeners.notifyPostedLocked(r, old, false);
+        mListeners.notifyPostedLocked(r1, old1, true);
+        mListeners.notifyPostedLocked(r1, old1, false);
         verify(mListeners, times(2)).getServices();
 
-        // in the lockdown mode
-        reset(r);
-        reset(old);
+        // Reset
+        reset(r0);
+        reset(old0);
+        reset(r1);
+        reset(old1);
         reset(mListeners);
-        when(mNm.isInLockDownMode()).thenReturn(true);
-        mListeners.notifyPostedLocked(r, old, true);
-        mListeners.notifyPostedLocked(r, old, false);
+
+        // Only user 0 is in the lockdown mode
+        when(r0.getUser()).thenReturn(uh0);
+        when(uh0.getIdentifier()).thenReturn(0);
+        when(mNm.isInLockDownMode(0)).thenReturn(true);
+
+        when(r1.getUser()).thenReturn(uh1);
+        when(uh1.getIdentifier()).thenReturn(1);
+        when(mNm.isInLockDownMode(1)).thenReturn(false);
+
+        mListeners.notifyPostedLocked(r0, old0, true);
+        mListeners.notifyPostedLocked(r0, old0, false);
         verify(mListeners, never()).getServices();
-    }
 
-    @Test
-    public void testnotifyRankingUpdateLockedInLockdownMode() {
-        List chn = mock(List.class);
-
-        // before the lockdown mode
-        when(mNm.isInLockDownMode()).thenReturn(false);
-        mListeners.notifyRankingUpdateLocked(chn);
-        verify(chn, times(1)).size();
-
-        // in the lockdown mode
-        reset(chn);
-        when(mNm.isInLockDownMode()).thenReturn(true);
-        mListeners.notifyRankingUpdateLocked(chn);
-        verify(chn, never()).size();
+        mListeners.notifyPostedLocked(r1, old1, true);
+        mListeners.notifyPostedLocked(r1, old1, false);
+        verify(mListeners, times(2)).getServices();
     }
 
     @Test
     public void testNotifyRemovedLockedInLockdownMode() throws NoSuchFieldException {
+        NotificationRecord r0 = mock(NotificationRecord.class);
+        NotificationStats rs0 = mock(NotificationStats.class);
+        UserHandle uh0 = mock(UserHandle.class);
+
+        NotificationRecord r1 = mock(NotificationRecord.class);
+        NotificationStats rs1 = mock(NotificationStats.class);
+        UserHandle uh1 = mock(UserHandle.class);
+
         StatusBarNotification sbn = mock(StatusBarNotification.class);
-        NotificationRecord r = mock(NotificationRecord.class);
-        NotificationStats rs = mock(NotificationStats.class);
-        FieldSetter.setField(r,
+        FieldSetter.setField(r0,
+                NotificationRecord.class.getDeclaredField("sbn"),
+                sbn);
+        FieldSetter.setField(r1,
                 NotificationRecord.class.getDeclaredField("sbn"),
                 sbn);
         FieldSetter.setField(mNm,
                 NotificationManagerService.class.getDeclaredField("mHandler"),
                 mock(NotificationManagerService.WorkerHandler.class));
 
-        // before the lockdown mode
-        when(mNm.isInLockDownMode()).thenReturn(false);
-        mListeners.notifyRemovedLocked(r, 0, rs);
-        mListeners.notifyRemovedLocked(r, 0, rs);
-        verify(sbn, times(2)).cloneLight();
+        // Neither user0 and user1 is in the lockdown mode
+        when(r0.getUser()).thenReturn(uh0);
+        when(uh0.getIdentifier()).thenReturn(0);
+        when(mNm.isInLockDownMode(0)).thenReturn(false);
+
+        when(r1.getUser()).thenReturn(uh1);
+        when(uh1.getIdentifier()).thenReturn(1);
+        when(mNm.isInLockDownMode(1)).thenReturn(false);
+
+        mListeners.notifyRemovedLocked(r0, 0, rs0);
+        mListeners.notifyRemovedLocked(r0, 0, rs0);
+        verify(sbn, atLeast(2)).cloneLight();
 
-        // in the lockdown mode
         reset(sbn);
-        reset(r);
-        reset(rs);
-        when(mNm.isInLockDownMode()).thenReturn(true);
-        mListeners.notifyRemovedLocked(r, 0, rs);
-        mListeners.notifyRemovedLocked(r, 0, rs);
+	mListeners.notifyRemovedLocked(r1, 0, rs1);
+        mListeners.notifyRemovedLocked(r1, 0, rs1);
+        verify(sbn, atLeast(2)).cloneLight();
+
+        // Reset
+	reset(sbn);
+        reset(r0);
+        reset(rs0);
+        reset(r1);
+        reset(rs1);
+
+        // Only user 0 is in the lockdown mode
+        when(r0.getUser()).thenReturn(uh0);
+        when(uh0.getIdentifier()).thenReturn(0);
+        when(mNm.isInLockDownMode(0)).thenReturn(true);
+
+        when(r1.getUser()).thenReturn(uh1);
+        when(uh1.getIdentifier()).thenReturn(1);
+        when(mNm.isInLockDownMode(1)).thenReturn(false);
+
+        mListeners.notifyRemovedLocked(r0, 0, rs0);
+        mListeners.notifyRemovedLocked(r0, 0, rs0);
         verify(sbn, never()).cloneLight();
+
+        mListeners.notifyRemovedLocked(r1, 0, rs1);
+        mListeners.notifyRemovedLocked(r1, 0, rs1);
+        verify(sbn, atLeast(2)).cloneLight();
     }
 }
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 5030e124e4ce..6c1620751866 100755
--- a/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
+++ b/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
@@ -124,6 +124,7 @@ import android.provider.MediaStore;
 import android.provider.Settings;
 import android.service.notification.Adjustment;
 import android.service.notification.NotificationListenerService;
+import android.service.notification.NotificationRankingUpdate;
 import android.service.notification.NotificationStats;
 import android.service.notification.StatusBarNotification;
 import android.service.notification.ZenPolicy;
@@ -149,6 +150,7 @@ import com.android.server.SystemService;
 import com.android.server.UiServiceTestCase;
 import com.android.server.lights.Light;
 import com.android.server.lights.LightsManager;
+import com.android.server.notification.ManagedServices.ManagedServiceInfo;
 import com.android.server.notification.NotificationManagerService.NotificationAssistants;
 import com.android.server.notification.NotificationManagerService.NotificationListeners;
 import com.android.server.pm.PackageManagerService;
@@ -264,6 +266,9 @@ public class NotificationManagerServiceTest extends UiServiceTestCase {
         @Nullable
         NotificationAssistantAccessGrantedCallback mNotificationAssistantAccessGrantedCallback;
 
+        @Nullable
+        Boolean mIsVisibleToListenerReturnValue = null;
+
         TestableNotificationManagerService(Context context) {
             super(context);
         }
@@ -333,6 +338,18 @@ public class NotificationManagerServiceTest extends UiServiceTestCase {
             return true;
         }
 
+        protected void setIsVisibleToListenerReturnValue(boolean value) {
+            mIsVisibleToListenerReturnValue = value;
+        }
+
+        @Override
+        boolean isVisibleToListener(StatusBarNotification sbn, ManagedServiceInfo listener) {
+            if (mIsVisibleToListenerReturnValue != null) {
+                return mIsVisibleToListenerReturnValue;
+            }
+            return super.isVisibleToListener(sbn, listener);
+        }
+
         class StrongAuthTrackerFake extends NotificationManagerService.StrongAuthTracker {
             private int mGetStrongAuthForUserReturnValue = 0;
             StrongAuthTrackerFake(Context context) {
@@ -5607,10 +5624,10 @@ public class NotificationManagerServiceTest extends UiServiceTestCase {
         mStrongAuthTracker.setGetStrongAuthForUserReturnValue(
                 STRONG_AUTH_REQUIRED_AFTER_USER_LOCKDOWN);
         mStrongAuthTracker.onStrongAuthRequiredChanged(mContext.getUserId());
-        assertTrue(mStrongAuthTracker.isInLockDownMode());
-        mStrongAuthTracker.setGetStrongAuthForUserReturnValue(0);
+        assertTrue(mStrongAuthTracker.isInLockDownMode(mContext.getUserId()));
+        mStrongAuthTracker.setGetStrongAuthForUserReturnValue(mContext.getUserId());
         mStrongAuthTracker.onStrongAuthRequiredChanged(mContext.getUserId());
-        assertFalse(mStrongAuthTracker.isInLockDownMode());
+        assertFalse(mStrongAuthTracker.isInLockDownMode(mContext.getUserId()));
     }
 
     @Test
@@ -5626,8 +5643,8 @@ public class NotificationManagerServiceTest extends UiServiceTestCase {
         // when entering the lockdown mode, cancel the 2 notifications.
         mStrongAuthTracker.setGetStrongAuthForUserReturnValue(
                 STRONG_AUTH_REQUIRED_AFTER_USER_LOCKDOWN);
-        mStrongAuthTracker.onStrongAuthRequiredChanged(mContext.getUserId());
-        assertTrue(mStrongAuthTracker.isInLockDownMode());
+        mStrongAuthTracker.onStrongAuthRequiredChanged(0);
+        assertTrue(mStrongAuthTracker.isInLockDownMode(0));
 
         // the notifyRemovedLocked function is called twice due to REASON_LOCKDOWN.
         ArgumentCaptor<Integer> captor = ArgumentCaptor.forClass(Integer.class);
@@ -5636,9 +5653,44 @@ public class NotificationManagerServiceTest extends UiServiceTestCase {
 
         // exit lockdown mode.
         mStrongAuthTracker.setGetStrongAuthForUserReturnValue(0);
-        mStrongAuthTracker.onStrongAuthRequiredChanged(mContext.getUserId());
+        mStrongAuthTracker.onStrongAuthRequiredChanged(0);
+        assertFalse(mStrongAuthTracker.isInLockDownMode(0));
 
         // the notifyPostedLocked function is called twice.
         verify(mListeners, times(2)).notifyPostedLocked(any(), any());
     }
+
+    @Test
+    public void testMakeRankingUpdateLockedInLockDownMode() {
+        // post 2 notifications from a same package
+        NotificationRecord pkgA = new NotificationRecord(mContext,
+                generateSbn("a", 1000, 9, 0), mTestNotificationChannel);
+        mService.addNotification(pkgA);
+        NotificationRecord pkgB = new NotificationRecord(mContext,
+                generateSbn("a", 1000, 9, 1), mTestNotificationChannel);
+        mService.addNotification(pkgB);
+
+        mService.setIsVisibleToListenerReturnValue(true);
+        NotificationRankingUpdate nru = mService.makeRankingUpdateLocked(null);
+        assertEquals(2, nru.getRankingMap().getOrderedKeys().length);
+
+        // when only user 0 entering the lockdown mode, its notification will be suppressed.
+        mStrongAuthTracker.setGetStrongAuthForUserReturnValue(
+                STRONG_AUTH_REQUIRED_AFTER_USER_LOCKDOWN);
+        mStrongAuthTracker.onStrongAuthRequiredChanged(0);
+        assertTrue(mStrongAuthTracker.isInLockDownMode(0));
+        assertFalse(mStrongAuthTracker.isInLockDownMode(1));
+
+        nru = mService.makeRankingUpdateLocked(null);
+        assertEquals(1, nru.getRankingMap().getOrderedKeys().length);
+
+        // User 0 exits lockdown mode. Its notification will be resumed.
+        mStrongAuthTracker.setGetStrongAuthForUserReturnValue(0);
+        mStrongAuthTracker.onStrongAuthRequiredChanged(0);
+        assertFalse(mStrongAuthTracker.isInLockDownMode(0));
+        assertFalse(mStrongAuthTracker.isInLockDownMode(1));
+
+        nru = mService.makeRankingUpdateLocked(null);
+        assertEquals(2, nru.getRankingMap().getOrderedKeys().length);
+    }
 }
