Update BackupEligibilityRules

1. Remove unused appIgnoresIncludeExcludeRules() and associated tests
2. Remove logic for enforcing full backup for apps with k/v agents and
   associated tests
3. Only ignore allowBackup for non-system apps in D2D and guard the
   behavior by target SDK

Bug: 183147249
Test: atest BackupEligibilityRulesTest
Change-Id: Id8b0862dae492de69c553858e27859970278d7db

2 files changed, 15 insertions, 92 deletions

diff --git a/services/backup/java/com/android/server/backup/utils/BackupEligibilityRules.java b/services/backup/java/com/android/server/backup/utils/BackupEligibilityRules.java
index 002f6d7e7790..818155c6c14b 100644
--- a/services/backup/java/com/android/server/backup/utils/BackupEligibilityRules.java
+++ b/services/backup/java/com/android/server/backup/utils/BackupEligibilityRules.java
@@ -71,6 +71,14 @@ public class BackupEligibilityRules {
     @EnabledSince(targetSdkVersion = Build.VERSION_CODES.S)
     static final long RESTRICT_ADB_BACKUP = 171032338L;
 
+    /**
+     * When  this change is enabled, {@code android:allowBackup}  is ignored for apps during D2D
+     * (device-to-device) migrations.
+     */
+    @ChangeId
+    @EnabledSince(targetSdkVersion = Build.VERSION_CODES.S)
+    static final long IGNORE_ALLOW_BACKUP_IN_D2D = 183147249L;
+
     public static BackupEligibilityRules forBackup(PackageManager packageManager,
             PackageManagerInternal packageManagerInternal,
             int userId) {
@@ -148,13 +156,15 @@ public class BackupEligibilityRules {
     * @return boolean indicating whether backup is allowed.
     */
     public boolean isAppBackupAllowed(ApplicationInfo app) {
-        boolean isSystemApp = UserHandle.isCore(app.uid);
         boolean allowBackup = (app.flags & ApplicationInfo.FLAG_ALLOW_BACKUP) != 0;
         switch (mOperationType) {
             case OperationType.MIGRATION:
                 // Backup / restore of all non-system apps is force allowed during
                 // device-to-device migration.
-                return !isSystemApp || allowBackup;
+                boolean isSystemApp = (app.flags & ApplicationInfo.FLAG_SYSTEM) != 0;
+                boolean ignoreAllowBackup = !isSystemApp && CompatChanges.isChangeEnabled(
+                        IGNORE_ALLOW_BACKUP_IN_D2D, app.packageName, UserHandle.of(mUserId));
+                return ignoreAllowBackup || allowBackup;
             case OperationType.ADB_BACKUP:
                 String packageName = app.packageName;
                 if (packageName == null) {
@@ -176,7 +186,7 @@ public class BackupEligibilityRules {
 
                 boolean isPrivileged = (app.flags & ApplicationInfo.PRIVATE_FLAG_PRIVILEGED) != 0;
                 boolean isDebuggable = (app.flags & ApplicationInfo.FLAG_DEBUGGABLE) != 0;
-                if (isSystemApp || isPrivileged) {
+                if (UserHandle.isCore(app.uid) || isPrivileged) {
                     try {
                         return mPackageManager.getProperty(PackageManager.PROPERTY_ALLOW_ADB_BACKUP,
                                 packageName).getBoolean();
@@ -283,11 +293,6 @@ public class BackupEligibilityRules {
      */
     @VisibleForTesting
     public boolean appGetsFullBackup(PackageInfo pkg) {
-        if (forceFullBackup(pkg.applicationInfo.uid, mOperationType)) {
-            // If this is a migration, all non-system packages get full backup.
-            return true;
-        }
-
         if (pkg.applicationInfo.backupAgentName != null) {
             // If it has an agent, it gets full backups only if it says so
             return (pkg.applicationInfo.flags & ApplicationInfo.FLAG_FULL_BACKUP_ONLY) != 0;
@@ -297,15 +302,6 @@ public class BackupEligibilityRules {
         return true;
     }
 
-    public boolean appIgnoresIncludeExcludeRules(ApplicationInfo app) {
-        return forceFullBackup(app.uid, mOperationType);
-    }
-
-    private boolean forceFullBackup(int appUid, @OperationType int operationType) {
-        return operationType == OperationType.MIGRATION &&
-                !UserHandle.isCore(appUid);
-    }
-
     /**
      * Returns whether the app is only capable of doing key/value. We say it's not if it allows full
      * backup, and it is otherwise.
diff --git a/services/tests/servicestests/src/com/android/server/backup/utils/BackupEligibilityRulesTest.java b/services/tests/servicestests/src/com/android/server/backup/utils/BackupEligibilityRulesTest.java
index 738527e1df0b..7323096121c4 100644
--- a/services/tests/servicestests/src/com/android/server/backup/utils/BackupEligibilityRulesTest.java
+++ b/services/tests/servicestests/src/com/android/server/backup/utils/BackupEligibilityRulesTest.java
@@ -219,6 +219,7 @@ public class BackupEligibilityRulesTest {
     }
 
     @Test
+    @EnableCompatChanges({BackupEligibilityRules.IGNORE_ALLOW_BACKUP_IN_D2D})
     public void appIsEligibleForBackup_backupNotAllowedAndInMigration_returnsTrue()
             throws Exception {
         ApplicationInfo applicationInfo = getApplicationInfo(Process.FIRST_APPLICATION_UID,
@@ -235,7 +236,7 @@ public class BackupEligibilityRulesTest {
     public void appIsEligibleForBackup_backupNotAllowedForSystemAppAndInMigration_returnsFalse()
             throws Exception {
         ApplicationInfo applicationInfo = getApplicationInfo(Process.SYSTEM_UID,
-                /* flags */ 0, CUSTOM_BACKUP_AGENT_NAME);
+                ApplicationInfo.FLAG_SYSTEM, CUSTOM_BACKUP_AGENT_NAME);
         BackupEligibilityRules eligibilityRules = getBackupEligibilityRules(
                 OperationType.MIGRATION);
         boolean isEligible = eligibilityRules.appIsEligibleForBackup(applicationInfo);
@@ -478,34 +479,6 @@ public class BackupEligibilityRulesTest {
     }
 
     @Test
-    public void appGetsFullBackup_withCustomBackupAgentAndWithoutFullBackupOnlyFlagAndInMigration_returnsTrue()
-            throws Exception {
-        PackageInfo packageInfo = new PackageInfo();
-        packageInfo.applicationInfo = getApplicationInfo(Process.FIRST_APPLICATION_UID,
-                ~ApplicationInfo.FLAG_FULL_BACKUP_ONLY, CUSTOM_BACKUP_AGENT_NAME);
-
-        BackupEligibilityRules eligibilityRules = getBackupEligibilityRules(
-                OperationType.MIGRATION);
-        boolean result = eligibilityRules.appGetsFullBackup(packageInfo);
-
-        assertThat(result).isTrue();
-    }
-
-    @Test
-    public void appGetsFullBackup_systemAppWithCustomBackupAgentAndWithoutFullBackupOnlyFlagAndInMigration_returnsFalse()
-            throws Exception {
-        PackageInfo packageInfo = new PackageInfo();
-        packageInfo.applicationInfo = getApplicationInfo(Process.SYSTEM_UID,
-                ~ApplicationInfo.FLAG_FULL_BACKUP_ONLY, CUSTOM_BACKUP_AGENT_NAME);
-
-        BackupEligibilityRules eligibilityRules = getBackupEligibilityRules(
-                OperationType.MIGRATION);
-        boolean result = eligibilityRules.appGetsFullBackup(packageInfo);
-
-        assertThat(result).isFalse();
-    }
-
-    @Test
     public void appIsKeyValueOnly_noCustomBackupAgent_returnsTrue() throws Exception {
         PackageInfo packageInfo = new PackageInfo();
         packageInfo.applicationInfo = new ApplicationInfo();
@@ -543,52 +516,6 @@ public class BackupEligibilityRulesTest {
     }
 
     @Test
-    public void appIgnoresIncludeExcludeRules_systemAppAndInMigration_returnsFalse() {
-        ApplicationInfo applicationInfo = new ApplicationInfo();
-        applicationInfo.uid = Process.SYSTEM_UID;
-
-        BackupEligibilityRules eligibilityRules = getBackupEligibilityRules(
-                OperationType.MIGRATION);
-        boolean result = eligibilityRules.appIgnoresIncludeExcludeRules(applicationInfo);
-
-        assertThat(result).isFalse();
-    }
-
-    @Test
-    public void appIgnoresIncludeExcludeRules_systemAppInBackup_returnsFalse() {
-        ApplicationInfo applicationInfo = new ApplicationInfo();
-        applicationInfo.uid = Process.SYSTEM_UID;
-
-        BackupEligibilityRules eligibilityRules = getBackupEligibilityRules(
-                OperationType.MIGRATION);
-        boolean result = eligibilityRules.appIgnoresIncludeExcludeRules(applicationInfo);
-
-        assertThat(result).isFalse();
-    }
-
-    @Test
-    public void appIgnoresIncludeExcludeRules_nonSystemAppInMigration_returnsTrue() {
-        ApplicationInfo applicationInfo = new ApplicationInfo();
-        applicationInfo.uid = Process.FIRST_APPLICATION_UID;
-
-        BackupEligibilityRules eligibilityRules = getBackupEligibilityRules(
-                OperationType.MIGRATION);
-        boolean result = eligibilityRules.appIgnoresIncludeExcludeRules(applicationInfo);
-
-        assertThat(result).isTrue();
-    }
-
-    @Test
-    public void appIgnoresIncludeExcludeRules_nonSystemInBackup_returnsFalse() {
-        ApplicationInfo applicationInfo = new ApplicationInfo();
-        applicationInfo.uid = Process.FIRST_APPLICATION_UID;
-
-        boolean result = mBackupEligibilityRules.appIgnoresIncludeExcludeRules(applicationInfo);
-
-        assertThat(result).isFalse();
-    }
-
-    @Test
     public void signaturesMatch_targetIsNull_returnsFalse() throws Exception {
         boolean result = mBackupEligibilityRules.signaturesMatch(new Signature[] {SIGNATURE_1}, null);