Skip backup/restore of wallpaper package

Do not backup or restore wallpaper package when
'backup_skip_user_facing_data' is set. See https://b.corp.google.com/issues/153940088#comment2 for context.

Bug: 153940088
Test: 1. atest UserBackupManagerServiceTest
      2. atest PerformUnifiedRestoreTaskTest
      3. atest CtsBackupTestCases
      4. atest CtsBackupHostTestCases
      5. Manual:
          1) adb shell settings secure put backup_skip_user_facing_data
	  1
	  2) adb shell bmgr backupnow com.android.wallpaperbackup ->
	  verify skipped
	  3) adb shell bmgr restore 1 com.android.wallpaperbackup ->
	  verify skipped
	  4) adb shell settings secure put backup_skip_user_facing_data
	  0 -> verify com.android.wallpaperbackup is backed up /
	  restored

Change-Id: Iedd0c4030a635e294a04d35bd525ca852c929b92

3 files changed, 43 insertions, 1 deletions

diff --git a/services/backup/java/com/android/server/backup/UserBackupManagerService.java b/services/backup/java/com/android/server/backup/UserBackupManagerService.java
index 992e98473ae7..dc35c774f71e 100644
--- a/services/backup/java/com/android/server/backup/UserBackupManagerService.java
+++ b/services/backup/java/com/android/server/backup/UserBackupManagerService.java
@@ -318,6 +318,9 @@ public class UserBackupManagerService {
 
     private static final String SERIAL_ID_FILE = "serial_id";
 
+    private static final String SKIP_USER_FACING_DATA = "backup_skip_user_facing_data";
+    private static final String WALLPAPER_PACKAGE = "com.android.wallpaperbackup";
+
     private final @UserIdInt int mUserId;
     private final BackupAgentTimeoutParameters mAgentTimeoutParameters;
     private final TransportManager mTransportManager;
@@ -3553,6 +3556,40 @@ public class UserBackupManagerService {
         }
     }
 
+    /**
+     * We want to skip backup/restore of certain packages if 'backup_skip_user_facing_data' is
+     * set to true in secure settings. See b/153940088 for details.
+     *
+     * TODO(b/154822946): Remove this logic in the next release.
+     */
+    public List<PackageInfo> filterUserFacingPackages(List<PackageInfo> packages) {
+        if (!shouldSkipUserFacingData()) {
+            return packages;
+        }
+
+        List<PackageInfo> filteredPackages = new ArrayList<>(packages.size());
+        for (PackageInfo packageInfo : packages)  {
+            if (!shouldSkipPackage(packageInfo.packageName)) {
+                filteredPackages.add(packageInfo);
+            } else {
+                Slog.i(TAG, "Will skip backup/restore for " + packageInfo.packageName);
+            }
+        }
+
+        return filteredPackages;
+    }
+
+    @VisibleForTesting
+    public boolean shouldSkipUserFacingData() {
+        return Settings.Secure.getInt(mContext.getContentResolver(), SKIP_USER_FACING_DATA,
+                /* def */ 0) != 0;
+    }
+
+    @VisibleForTesting
+    public boolean shouldSkipPackage(String packageName) {
+        return WALLPAPER_PACKAGE.equals(packageName);
+    }
+
     private void updateStateForTransport(String newTransportName) {
         // Publish the name change
         Settings.Secure.putStringForUser(mContext.getContentResolver(),
diff --git a/services/backup/java/com/android/server/backup/fullbackup/PerformFullTransportBackupTask.java b/services/backup/java/com/android/server/backup/fullbackup/PerformFullTransportBackupTask.java
index f7f01387cf78..738dd9bf0f0d 100644
--- a/services/backup/java/com/android/server/backup/fullbackup/PerformFullTransportBackupTask.java
+++ b/services/backup/java/com/android/server/backup/fullbackup/PerformFullTransportBackupTask.java
@@ -61,6 +61,7 @@ import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.List;
 import java.util.Objects;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
@@ -131,7 +132,7 @@ public class PerformFullTransportBackupTask extends FullBackupTask implements Ba
     private UserBackupManagerService mUserBackupManagerService;
     private final Object mCancelLock = new Object();
 
-    ArrayList<PackageInfo> mPackages;
+    List<PackageInfo> mPackages;
     PackageInfo mCurrentPackage;
     boolean mUpdateSchedule;
     CountDownLatch mLatch;
@@ -249,6 +250,8 @@ public class PerformFullTransportBackupTask extends FullBackupTask implements Ba
                         null);
             }
         }
+
+        mPackages = backupManagerService.filterUserFacingPackages(mPackages);
     }
 
     private void registerTask() {
diff --git a/services/backup/java/com/android/server/backup/restore/PerformUnifiedRestoreTask.java b/services/backup/java/com/android/server/backup/restore/PerformUnifiedRestoreTask.java
index e434be648dcb..12113fea12a4 100644
--- a/services/backup/java/com/android/server/backup/restore/PerformUnifiedRestoreTask.java
+++ b/services/backup/java/com/android/server/backup/restore/PerformUnifiedRestoreTask.java
@@ -270,6 +270,8 @@ public class PerformUnifiedRestoreTask implements BackupRestoreTask {
             }
         }
 
+        mAcceptSet = backupManagerService.filterUserFacingPackages(mAcceptSet);
+
         if (MORE_DEBUG) {
             Slog.v(TAG, "Restore; accept set size is " + mAcceptSet.size());
             for (PackageInfo info : mAcceptSet) {