Add initial export function to save the database as plain-text JSON file

app/src/main/AndroidManifest.xml

@@ -2,6 +2,9 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools"
     package="org.shadowice.flocke.andotp">
 
+    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
+
     <application
         android:allowBackup="false"
         android:icon="@mipmap/ic_launcher"

app/src/main/java/org/shadowice/flocke/andotp/MainActivity.java

@@ -26,6 +26,7 @@ import android.Manifest;
 import android.animation.ObjectAnimator;
 import android.app.Activity;
 import android.app.AlertDialog;
+import android.content.DialogInterface;
 import android.content.Intent;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
@@ -65,6 +66,7 @@ public class MainActivity extends AppCompatActivity {
     private Runnable handlerTask;
 
     private static final int PERMISSIONS_REQUEST_CAMERA = 42;
+    private static final int PERMISSIONS_REQUEST_WRITE_EXPORT = 24;
 
     private void doScanQRCode(){
         new IntentIntegrator(MainActivity.this)
@@ -74,17 +76,14 @@ public class MainActivity extends AppCompatActivity {
     }
 
     private void scanQRCode(){
-        // check Android 6 permission
         if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED) {
             doScanQRCode();
         } else {
-            ActivityCompat.requestPermissions(this,
+            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA}, PERMISSIONS_REQUEST_CAMERA);
-                    new String[]{Manifest.permission.CAMERA}, PERMISSIONS_REQUEST_CAMERA);
         }
     }
 
     private void showAbout() {
-        // Inflate the dialog_about message contents
         View messageView = getLayoutInflater().inflate(R.layout.dialog_about, null, false);
 
         String versionName = "";
@@ -106,31 +105,72 @@ public class MainActivity extends AppCompatActivity {
         builder.show();
     }
 
+    private void doExportJSON() {
+        boolean success = SettingsHelper.exportAsJSON(this);
+
+        if (success)
+            showSimpleSnackbar(R.string.msg_export_success);
+    }
+
+    private void exportJSON() {
+        if (ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
+            doExportJSON();
+        } else {
+            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, PERMISSIONS_REQUEST_WRITE_EXPORT);
+        }
+    }
+
+    private void exportJSONWithWarning() {
+        AlertDialog.Builder builder = new AlertDialog.Builder(this);
+
+        builder.setTitle(getString(R.string.msg_security_warning))
+                .setMessage(getString(R.string.msg_export_warning))
+                .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialogInterface, int i) {
+                        exportJSON();
+                    }
+                })
+                .setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialogInterface, int i) {}
+                })
+                .setIcon(android.R.drawable.ic_dialog_alert)
+                .show();
+    }
+
     @Override
     public void onRequestPermissionsResult(int requestCode, @NonNull String permissions[], @NonNull int[] grantResults) {
        if(requestCode == PERMISSIONS_REQUEST_CAMERA) {
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
-               // permission was granted
                doScanQRCode();
            } else {
-               Snackbar.make(fab, R.string.msg_camera_permission, Snackbar.LENGTH_LONG).setCallback(new Snackbar.Callback() {
+               showSimpleSnackbar(R.string.msg_camera_permission);
-                   @Override
-                   public void onDismissed(Snackbar snackbar, int event) {
-                       super.onDismissed(snackbar, event);
-
-                       if (entries.isEmpty()) {
-                           showNoAccount();
-                       }
-                   }
-               }).show();
            }
-       }
+       } else if (requestCode == PERMISSIONS_REQUEST_WRITE_EXPORT) {
-       else {
+           if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
+               doExportJSON();
+           } else {
+               showSimpleSnackbar(R.string.msg_storage_permissions);
+           }
+       } else {
            super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        }
     }
 
-    private Entry nextSelection = null;
+    private void showSimpleSnackbar(int string_res) {
+        Snackbar.make(fab, string_res, Snackbar.LENGTH_LONG).setCallback(new Snackbar.Callback() {
+            @Override
+            public void onDismissed(Snackbar snackbar, int event) {
+                super.onDismissed(snackbar, event);
+
+                if (entries.isEmpty()) {
+                    showNoAccount();
+                }
+            }
+        }).show();
+    }
+
     private void showNoAccount(){
         Snackbar noAccountSnackbar = Snackbar.make(fab, R.string.no_accounts, Snackbar.LENGTH_INDEFINITE)
                 .setAction(R.string.button_add, new View.OnClickListener() {
@@ -286,7 +326,15 @@ public class MainActivity extends AppCompatActivity {
     public boolean onOptionsItemSelected(MenuItem item) {
         int id = item.getItemId();
 
-        if(id == R.id.action_about){
+        if (id == R.id.action_export) {
+            exportJSONWithWarning();
+
+            return true;
+        } else if (id == R.id.action_import) {
+            SettingsHelper.importFromJSON(this);
+
+            return true;
+        } else if (id == R.id.action_about){
             showAbout();
 
             return true;

app/src/main/java/org/shadowice/flocke/andotp/SettingsHelper.java

@@ -27,11 +27,15 @@ import android.content.Context;
 import org.json.JSONArray;
 import org.json.JSONException;
 
+import java.io.BufferedWriter;
 import java.io.File;
+import java.io.FileWriter;
+import java.io.Writer;
 import java.util.ArrayList;
 
 import javax.crypto.SecretKey;
 
+import static android.os.Environment.getExternalStorageDirectory;
 import static org.shadowice.flocke.andotp.Utils.readFully;
 import static org.shadowice.flocke.andotp.Utils.writeFully;
 
@@ -39,6 +43,8 @@ public class SettingsHelper {
     public static final String KEY_FILE = "otp.key";
     public static final String SETTINGS_FILE = "secrets.dat";
 
+    public static final String EXPORT_FILE = "otp_accounts.json";
+
     public static void store(Context context, ArrayList<Entry> entries){
         JSONArray a = new JSONArray();
 
@@ -81,4 +87,44 @@ public class SettingsHelper {
         }
         return entries;
     }
+
+    public static JSONArray readJSON(Context context) {
+        JSONArray json = new JSONArray();
+
+        try {
+            byte[] data = readFully(new File(context.getFilesDir() + "/" + SETTINGS_FILE));
+
+            SecretKey key = EncryptionHelper.loadOrGenerateKeys(context, new File(context.getFilesDir() + "/" + KEY_FILE));
+            data = EncryptionHelper.decrypt(key, data);
+
+            json = new JSONArray(new String(data));
+        }
+        catch (Exception e) {
+        }
+
+        return json;
+    }
+
+    public static boolean exportAsJSON(Context context) {
+        File outputFile = new File(getExternalStorageDirectory() + "/" + EXPORT_FILE);
+
+        JSONArray data = readJSON(context);
+
+        boolean success = true;
+
+        try {
+            Writer output = new BufferedWriter(new FileWriter(outputFile));
+            output.write(data.toString());
+            output.close();
+        } catch (Exception e) {
+            success = false;
+            e.printStackTrace();
+        }
+
+        return success;
+    }
+
+    public static void importFromJSON(Context context) {
+
+    }
 }

app/src/main/res/menu/menu_main.xml

@@ -1,6 +1,25 @@
 <menu xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto">
 
+    <item
+        android:id="@+id/submenu_backup"
+        android:title="@string/menu_submenu_backup">
+
+        <menu>
+            <item
+                android:id="@+id/action_export"
+                android:orderInCategory="100"
+                android:title="@string/menu_export"
+                app:showAsAction="never" />
+
+            <item
+                android:id="@+id/action_import"
+                android:orderInCategory="100"
+                android:title="@string/menu_import"
+                app:showAsAction="never" />
+        </menu>
+    </item>
+
     <item
         android:id="@+id/action_about"
         android:orderInCategory="100"

app/src/main/res/values/strings.xml

@@ -6,6 +6,9 @@
     <string name="menu_edit">Edit</string>
     <string name="menu_scan">Scan QR Code</string>
     <string name="menu_about">About</string>
+    <string name="menu_submenu_backup">Import / Export</string>
+    <string name="menu_export">Export as JSON</string>
+    <string name="menu_import">Import from JSON</string>
     <string name="msg_invalid_qr_code">Invalid QR Code</string>
     <string name="msg_account_added">Account added</string>
     <string name="button_cancel">Cancel</string>
@@ -17,6 +20,13 @@
     <string name="alert_rename">Rename</string>
     <string name="alert_remove">"Remove "</string>
     <string name="msg_camera_permission">Camera permission not granted</string>
+    <string name="msg_storage_permissions">Storage permissions not granted</string>
+    <string name="msg_security_warning">Security warning</string>
+    <string name="msg_export_warning">
+        Do you really want to export the database as plain-text JSON file?
+        This file contains all your secret keys, please keep it safe!
+    </string>
+    <string name="msg_export_success">Export to external storage successful</string>
 
     <!-- About dialog -->
     <string name="about_description">An open-source two-factor authentication App for Android 4.3+</string>