Require password to FR in carrier demo mode

Bug: 34341567
Test: manual - password is not required for regular user factory
resets and is required in carrier demo mode.

Change-Id: Ic594ebafdac02fc467dc6b2e46dfbd520db3ce9f

src/com/android/settings/MasterClear.java

@@ -20,6 +20,7 @@ import android.accounts.Account;
 import android.accounts.AccountManager;
 import android.accounts.AuthenticatorDescription;
 import android.app.Activity;
+import android.app.FragmentManager;
 import android.content.Context;
 import android.content.Intent;
 import android.content.pm.PackageManager;
@@ -46,6 +47,7 @@ import android.widget.ScrollView;
 import android.widget.TextView;
 
 import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
+import com.android.settings.widget.CarrierDemoPasswordDialogFragment;
 import com.android.settingslib.RestrictedLockUtils;
 
 import java.util.List;
@@ -62,7 +64,8 @@ import static com.android.settingslib.RestrictedLockUtils.EnforcedAdmin;
  *
  * This is the initial screen.
  */
-public class MasterClear extends OptionsMenuFragment {
+public class MasterClear extends OptionsMenuFragment
+        implements CarrierDemoPasswordDialogFragment.Callback {
     private static final String TAG = "MasterClear";
 
     private static final int KEYGUARD_REQUEST = 55;
@@ -127,12 +130,23 @@ public class MasterClear extends OptionsMenuFragment {
     private final Button.OnClickListener mInitiateListener = new Button.OnClickListener() {
 
         public void onClick(View v) {
-            if (!runKeyguardConfirmation(KEYGUARD_REQUEST)) {
+            if ( Utils.isCarrierDemoUser(v.getContext())) {
+                // Require the carrier password before displaying the final confirmation.
+                final FragmentManager fm = getChildFragmentManager();
+                if (fm != null && !fm.isDestroyed()) {
+                    new CarrierDemoPasswordDialogFragment().show(fm, null /* tag */);
+                }
+            } else if (!runKeyguardConfirmation(KEYGUARD_REQUEST)) {
                 showFinalConfirmation();
             }
         }
     };
 
+    @Override
+    public void onPasswordVerified() {
+        showFinalConfirmation();
+    }
+
     /**
      * In its initial state, the activity presents a button for the user to
      * click in order to initiate a confirmation sequence.  This method is

src/com/android/settings/widget/CarrierDemoPasswordDialogFragment.java

@@ -0,0 +1,144 @@
+/*
+ * Copyright (C) 2017 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.settings.widget;
+
+import android.app.AlertDialog;
+import android.app.Dialog;
+import android.app.Fragment;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.content.res.TypedArray;
+import android.os.Bundle;
+import android.text.Editable;
+import android.text.InputType;
+import android.text.TextUtils;
+import android.text.TextWatcher;
+import android.util.Log;
+import android.view.inputmethod.InputMethodManager;
+import android.widget.Button;
+import android.widget.EditText;
+
+import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
+import com.android.internal.util.HexDump;
+import com.android.settings.R;
+
+import com.android.settings.core.instrumentation.InstrumentedDialogFragment;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
+public class CarrierDemoPasswordDialogFragment extends InstrumentedDialogFragment {
+
+    private static final String TAG = "CarrierDemoPasswordDF";
+
+    private MessageDigest mMessageDigest;
+
+    public CarrierDemoPasswordDialogFragment() {
+        try {
+            mMessageDigest = MessageDigest.getInstance("SHA-256");
+        } catch (NoSuchAlgorithmException e) {
+            Log.e(TAG, "Unable to verify demo mode password", e);
+        }
+    }
+
+    @Override
+    public Dialog onCreateDialog(Bundle savedInstanceState) {
+        final AlertDialog dialog = new AlertDialog.Builder(getContext())
+                .setPositiveButton(R.string.retail_demo_reset_next,
+                        new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int which) {
+                        final Fragment parentFragment = getParentFragment();
+                        if (parentFragment instanceof Callback
+                                && which == DialogInterface.BUTTON_POSITIVE) {
+                            ((Callback) parentFragment).onPasswordVerified();
+                        }
+                    }
+                })
+                .setNegativeButton(android.R.string.cancel, null)
+                .setMessage(R.string.retail_demo_reset_message)
+                .setTitle(R.string.retail_demo_reset_title)
+                .create();
+
+        final Context context = dialog.getContext();
+        final EditText passwordField = new EditText(context);
+        passwordField.setSingleLine();
+        passwordField.setInputType(InputType.TYPE_CLASS_TEXT
+                | InputType.TYPE_TEXT_VARIATION_PASSWORD);
+        passwordField.addTextChangedListener(new TextWatcher() {
+            @Override
+            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
+                // no-op
+            }
+
+            @Override
+            public void onTextChanged(CharSequence s, int start, int before, int count) {
+                verifyPassword(dialog, passwordField.getText().toString());
+            }
+
+            @Override
+            public void afterTextChanged(Editable s) {
+                // no-op
+            }
+        });
+
+        dialog.setOnShowListener(new DialogInterface.OnShowListener() {
+            @Override
+            public void onShow(DialogInterface dialogInterface) {
+                verifyPassword(dialog, passwordField.getText().toString());
+                passwordField.requestFocus();
+                final InputMethodManager imm = (InputMethodManager) getContext().getSystemService(
+                        Context.INPUT_METHOD_SERVICE);
+                imm.showSoftInput(passwordField, InputMethodManager.SHOW_IMPLICIT);
+            }
+        });
+        dialog.setCanceledOnTouchOutside(false);
+
+        final TypedArray a = context.obtainStyledAttributes(
+                new int[] { android.R.attr.dialogPreferredPadding });
+        final int sidePadding = a.getDimensionPixelSize(0, 0);
+        dialog.setView(passwordField, sidePadding, 0, sidePadding, 0);
+        a.recycle();
+
+        return dialog;
+    }
+
+    private void verifyPassword(AlertDialog dialog, String input) {
+        final Button positiveButton = dialog.getButton(DialogInterface.BUTTON_POSITIVE);
+        if (mMessageDigest == null || TextUtils.isEmpty(input)) {
+            positiveButton.setEnabled(false);
+            return;
+        }
+        final String passwordHash = getContext().getString(
+                com.android.internal.R.string.config_carrierDemoModePassword);
+        if (passwordHash == null || TextUtils.isEmpty(passwordHash)) {
+            // This device does not support carrier demo mode.
+            return;
+        }
+        final byte[] inputDigest = mMessageDigest.digest(input.getBytes());
+        final String inputHash = HexDump.toHexString(inputDigest, 0, inputDigest.length, false);
+        positiveButton.setEnabled(TextUtils.equals(passwordHash, inputHash));
+    }
+
+    @Override
+    public int getMetricsCategory() {
+        return MetricsEvent.CARRIER_DEMO_MODE_PASSWORD;
+    }
+
+    public interface Callback {
+        void onPasswordVerified();
+    }
+}