Disable user switching when the device is factory resetting.

On automotive, a factory reset request from the device admin can be
delayed as it would be a driving hazard, but the user should not be
switchable during this state.

Test: atest FrameworksMockingServicesTests:FactoryResetterTest
Test: manual verification using TestDpc

Fixes: 205874492
Bug: 225012970

Change-Id: I2b6cd7c56bf3714ccf79b9b092c8b67dd5817f0c

services/core/java/com/android/server/FactoryResetter.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2022 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.server;
+
+import android.content.Context;
+import android.content.pm.PackageManager;
+
+import com.android.internal.util.Preconditions;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/**
+ * TODO(b/225012970): add javadoc from {@code com.android.server.devicepolicy.FactoryResetter}
+ */
+public final class FactoryResetter {
+
+    private static final AtomicBoolean sFactoryResetting = new AtomicBoolean(false);
+
+    /**
+     * Checks whether a factory reset is in progress.
+     */
+    public static boolean isFactoryResetting() {
+        return sFactoryResetting.get();
+    }
+
+    /**
+     * @deprecated called by {@code com.android.server.devicepolicy.FactoryResetter}, won't be
+     * needed once that class logic is moved into this.
+     */
+    @Deprecated
+    public static void setFactoryResetting(Context context) {
+        Preconditions.checkCallAuthorization(context.checkCallingOrSelfPermission(
+                android.Manifest.permission.MASTER_CLEAR) == PackageManager.PERMISSION_GRANTED);
+        sFactoryResetting.set(true);
+    }
+
+    private FactoryResetter() {
+        throw new UnsupportedOperationException("Provides only static methods");
+    }
+}

services/core/java/com/android/server/am/UserController.java

@@ -106,6 +106,7 @@ import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.util.ArrayUtils;
 import com.android.internal.util.FrameworkStatsLog;
 import com.android.internal.widget.LockPatternUtils;
+import com.android.server.FactoryResetter;
 import com.android.server.FgThread;
 import com.android.server.LocalServices;
 import com.android.server.SystemServiceManager;
@@ -1765,6 +1766,10 @@ class UserController implements Handler.Callback {
             Slogf.w(TAG, "Cannot switch to User #" + targetUserId + ": not a full user");
             return false;
         }
+        if (FactoryResetter.isFactoryResetting()) {
+            Slogf.w(TAG, "Cannot switch to User #" + targetUserId + ": factory reset in progress");
+            return false;
+        }
         boolean userSwitchUiEnabled;
         synchronized (mLock) {
             if (!mInitialized) {

services/devicepolicy/java/com/android/server/devicepolicy/FactoryResetter.java

@@ -16,6 +16,8 @@
 
 package com.android.server.devicepolicy;
 
+import static com.android.server.FactoryResetter.setFactoryResetting;
+
 import android.annotation.Nullable;
 import android.app.admin.DevicePolicySafetyChecker;
 import android.content.Context;
@@ -36,7 +38,10 @@ import java.util.Objects;
 
 /**
  * Entry point for "factory reset" requests.
+ *
+ * @deprecated TODO(b/225012970): should be moved to {@code com.android.server.FactoryResetter}
  */
+@Deprecated
 public final class FactoryResetter {
 
     private static final String TAG = FactoryResetter.class.getSimpleName();
@@ -60,6 +65,8 @@ public final class FactoryResetter {
         Preconditions.checkCallAuthorization(mContext.checkCallingOrSelfPermission(
                 android.Manifest.permission.MASTER_CLEAR) == PackageManager.PERMISSION_GRANTED);
 
+        setFactoryResetting(mContext);
+
         if (mSafetyChecker == null) {
             factoryResetInternalUnchecked();
             return true;

services/tests/mockingservicestests/src/com/android/server/devicepolicy/FactoryResetterTest.java

@@ -14,11 +14,13 @@
  * limitations under the License.
  */
 
+// TODO(b/225012970): should be moved to com.android.server
 package com.android.server.devicepolicy;
 
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.doAnswer;
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.mockitoSession;
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.verify;
+import static com.android.server.FactoryResetter.isFactoryResetting;
 
 import static com.google.common.truth.Truth.assertThat;
 
@@ -165,6 +167,7 @@ public final class FactoryResetterTest {
                 .factoryReset();
 
         assertThat(success).isTrue();
+        assertThat(isFactoryResetting()).isTrue();
         verifyWipeAdoptableStorageCalled();
         verifyWipeFactoryResetProtectionNotCalled();
         verifyRebootWipeUserDataMinimumArgsCalled();
@@ -179,6 +182,7 @@ public final class FactoryResetterTest {
                 .build().factoryReset();
 
         assertThat(success).isTrue();
+        assertThat(isFactoryResetting()).isTrue();
         verifyWipeAdoptableStorageNotCalled();
         verifyWipeFactoryResetProtectionCalled();
         verifyRebootWipeUserDataMinimumArgsCalled();
@@ -198,6 +202,7 @@ public final class FactoryResetterTest {
                 .build().factoryReset();
 
         assertThat(success).isTrue();
+        assertThat(isFactoryResetting()).isTrue();
         verifyWipeAdoptableStorageCalled();
         verifyWipeFactoryResetProtectionCalled();
         verifyRebootWipeUserDataAllArgsCalled();
@@ -211,6 +216,7 @@ public final class FactoryResetterTest {
                 .setSafetyChecker(mSafetyChecker).build().factoryReset();
 
         assertThat(success).isFalse();
+        assertThat(isFactoryResetting()).isTrue();
         verifyWipeAdoptableStorageNotCalled();
         verifyWipeFactoryResetProtectionNotCalled();
         verifyRebootWipeUserDataNotCalled();
@@ -238,6 +244,7 @@ public final class FactoryResetterTest {
                 .build().factoryReset();
 
         assertThat(success).isFalse();
+        assertThat(isFactoryResetting()).isTrue();
         verifyWipeAdoptableStorageCalled();
         verifyWipeFactoryResetProtectionCalled();
         verifyRebootWipeUserDataAllArgsCalled();