Whitelist (alpha)

src/app/src/debug/res/drawable-anydpi/add.xml

@@ -0,0 +1,11 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24"
+    android:tint="#FFFFFF"
+    android:alpha="0.8">
+  <path
+      android:fillColor="@android:color/white"
+      android:pathData="M19,13h-6v6h-2v-6H5v-2h6V5h2v6h6v2z"/>
+</vector>

src/app/src/main/AndroidManifest.xml

@@ -23,6 +23,13 @@
         android:supportsRtl="true"
         android:theme="@style/Theme.LocateMyDevice"
         tools:targetApi="30">
+        <activity
+            android:name=".WhitelistContactsActivity"
+            android:exported="false">
+            <meta-data
+                android:name="android.app.lib_name"
+                android:value="" />
+        </activity>
         <activity
             android:name=".RingerActivity"
             android:exported="false">

src/app/src/main/java/com/xfarrow/locatemydevice/MainActivity.java

@@ -67,39 +67,6 @@ public class MainActivity extends AppCompatActivity {
         }
     }
 
-    @Override
-    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
-        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
-
-        // Grant Background location if and only if FINE_LOCATION is already granted
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
-            if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED
-            && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_BACKGROUND_LOCATION) != PackageManager.PERMISSION_GRANTED)
-            {
-                ActivityCompat.requestPermissions(this,
-                        new String[]{Manifest.permission.ACCESS_BACKGROUND_LOCATION},
-                        Utils.PERMISSION_ACCESS_BACKGROUND_LOCATION);
-            }
-        }
-    }
-
-    @Override
-    public boolean onCreateOptionsMenu(Menu menu) {
-        getMenuInflater().inflate(R.menu.menu, menu);
-        return super.onCreateOptionsMenu(menu);
-    }
-
-    @Override
-    public boolean onOptionsItemSelected(MenuItem item) {
-        int id = item.getItemId();
-
-        if (id == R.id.settings_button) {
-            Intent myIntent = new Intent(MainActivity.this, SettingsActivity.class);
-            MainActivity.this.startActivity(myIntent);
-        }
-        return super.onOptionsItemSelected(item);
-    }
-
     public void displayDrawOverlayPermissionDialog(){
         AlertDialog.Builder alert = new AlertDialog.Builder(this);
         alert.setTitle("Display over other apps");
@@ -129,4 +96,39 @@ public class MainActivity extends AppCompatActivity {
                 " permission to provide the 'lock' feature.");
         startActivity(intent);
     }
+
+    @Override
+    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
+        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
+
+        // Grant Background location if and only if FINE_LOCATION is already granted
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
+            if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED
+            && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_BACKGROUND_LOCATION) != PackageManager.PERMISSION_GRANTED)
+            {
+                ActivityCompat.requestPermissions(this,
+                        new String[]{Manifest.permission.ACCESS_BACKGROUND_LOCATION},
+                        Utils.PERMISSION_ACCESS_BACKGROUND_LOCATION);
+            }
+        }
+    }
+
+    // Add settings button on the top
+    @Override
+    public boolean onCreateOptionsMenu(Menu menu) {
+        getMenuInflater().inflate(R.menu.menu_settings, menu);
+        return super.onCreateOptionsMenu(menu);
+    }
+
+    // Settings button click
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        int id = item.getItemId();
+
+        if (id == R.id.settings_button) {
+            Intent myIntent = new Intent(MainActivity.this, SettingsActivity.class);
+            MainActivity.this.startActivity(myIntent);
+        }
+        return super.onOptionsItemSelected(item);
+    }
 }

src/app/src/main/java/com/xfarrow/locatemydevice/Settings.java

@@ -6,6 +6,7 @@ import android.content.SharedPreferences;
 public class Settings {
     public static final int PASSWORD = 0;
     public static final int SMS_COMMAND = 1;
+    public static final int WHITELIST_ENABLED = 2;
 
     private final SharedPreferences sharedPreferences;
 
@@ -29,6 +30,8 @@ public class Settings {
                 return CipherUtils.get256Sha("0000");
             case SMS_COMMAND:
                 return "LMD";
+            case WHITELIST_ENABLED:
+                return "false";
         }
         return null;
     }

src/app/src/main/java/com/xfarrow/locatemydevice/SettingsActivity.java

@@ -1,13 +1,17 @@
 package com.xfarrow.locatemydevice;
 
+import android.annotation.SuppressLint;
 import android.content.DialogInterface;
+import android.content.Intent;
 import android.os.Bundle;
 import android.text.Editable;
 import android.text.TextWatcher;
 import android.text.method.PasswordTransformationMethod;
 import android.view.View;
 import android.widget.Button;
+import android.widget.CompoundButton;
 import android.widget.EditText;
+import android.widget.Switch;
 import android.widget.Toast;
 
 import androidx.appcompat.app.AlertDialog;
@@ -17,6 +21,9 @@ public class SettingsActivity extends AppCompatActivity {
 
     private Button buttonEnterPin;
     private EditText editTextLmdCommand;
+    @SuppressLint("UseSwitchCompatOrMaterialCode")
+    private Switch whitelistSwitch;
+    private Button addContactsButton;
     private Settings settings;
 
     @Override
@@ -24,6 +31,7 @@ public class SettingsActivity extends AppCompatActivity {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.settings);
         settings = new Settings(this);
+
         setViews();
         setValues();
         setListeners();
@@ -32,6 +40,11 @@ public class SettingsActivity extends AppCompatActivity {
     private void setViews(){
         buttonEnterPin = findViewById(R.id.buttonEnterPassword);
         editTextLmdCommand = findViewById(R.id.editTextLmdCommand);
+        whitelistSwitch = findViewById(R.id.SwitchWhitelist);
+        addContactsButton = findViewById(R.id.buttonAddContacts);
+
+        addContactsButton.setEnabled(Boolean.parseBoolean(settings.get(Settings.WHITELIST_ENABLED)));
+        whitelistSwitch.setChecked(Boolean.parseBoolean(settings.get(Settings.WHITELIST_ENABLED)));
     }
 
     private void setValues(){
@@ -105,5 +118,22 @@ public class SettingsActivity extends AppCompatActivity {
                 }
             }
         });
+
+        whitelistSwitch.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
+            @Override
+            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
+                addContactsButton.setEnabled(isChecked);
+                settings.set(Settings.WHITELIST_ENABLED, String.valueOf(isChecked));
+            }
+        });
+
+        addContactsButton.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                Intent myIntent = new Intent(SettingsActivity.this, WhitelistContactsActivity.class);
+                SettingsActivity.this.startActivity(myIntent);
+            }
+        });
+
     }
 }

src/app/src/main/java/com/xfarrow/locatemydevice/SmsHandler.java

@@ -50,6 +50,12 @@ public class SmsHandler {
         String providedOption = "";
         String providedPassword = "";
 
+        // Deny communication to those not in the whitelist, if enabled
+        WhitelistDbHandler whitelistDbHandler = new WhitelistDbHandler(context);
+        if(Boolean.parseBoolean(settings.get(Settings.WHITELIST_ENABLED)) && !whitelistDbHandler.isContactPresent(sender)){
+            return;
+        }
+
         String regexToMatch = "^"
                 + command
                 + "\\s"

src/app/src/main/java/com/xfarrow/locatemydevice/WhitelistContactsActivity.java

@@ -0,0 +1,89 @@
+package com.xfarrow.locatemydevice;
+
+import androidx.appcompat.app.AppCompatActivity;
+
+import android.app.Activity;
+import android.content.Intent;
+import android.database.Cursor;
+import android.net.Uri;
+import android.os.Bundle;
+import android.provider.ContactsContract;
+import android.view.Menu;
+import android.view.MenuItem;
+import android.widget.ArrayAdapter;
+import android.widget.ListView;
+import android.widget.Toast;
+
+import java.util.ArrayList;
+
+public class WhitelistContactsActivity extends AppCompatActivity {
+
+    ListView contactsListView;
+    ArrayList<String> contacts;
+    ArrayAdapter<String> listviewAdapter;
+    WhitelistDbHandler whitelistDbHandler = new WhitelistDbHandler(this);
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_whitelist_contacts);
+        setTitle("Whitelist");
+        setViews();
+
+        contacts = whitelistDbHandler.getAllContacts();
+        listviewAdapter = new ArrayAdapter<String>(this,
+                android.R.layout.simple_list_item_1,
+                contacts);
+        contactsListView.setAdapter(listviewAdapter);
+    }
+
+    private void setViews(){
+        contactsListView = findViewById(R.id.ContactsListView);
+    }
+
+    // Add "add" button on the top
+    @Override
+    public boolean onCreateOptionsMenu(Menu menu) {
+        getMenuInflater().inflate(R.menu.menu_add, menu);
+        return super.onCreateOptionsMenu(menu);
+    }
+
+    // "Add contact" click
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        int id = item.getItemId();
+
+        if (id == R.id.add_button) {
+            Intent pickContact = new Intent(Intent.ACTION_PICK, ContactsContract.Contacts.CONTENT_URI);
+            pickContact.setType(ContactsContract.CommonDataKinds.Phone.CONTENT_TYPE);
+            startActivityForResult(pickContact, 123);
+        }
+        return super.onOptionsItemSelected(item);
+    }
+
+    // Gets fired when the user has chosen the contact
+    @Override
+    protected void onActivityResult (int requestCode, int resultCode, Intent data) {
+        super.onActivityResult(requestCode, resultCode, data);
+        if (resultCode == Activity.RESULT_OK && requestCode == 123) {
+            Uri contactData = data.getData();
+            Cursor c = getContentResolver().query(contactData, null, null, null, null);
+            if (c.moveToFirst()) {
+                int phoneIndex = c.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER);
+                String number = c.getString(phoneIndex).trim().replace("\\s+", "");
+                contactSelected(number);
+            }
+            c.close();
+        }
+    }
+
+    private void contactSelected(String number){
+        if(whitelistDbHandler.isContactPresent(number)){
+            Toast.makeText(this, "Contact already in the list", Toast.LENGTH_SHORT).show();
+            return;
+        }
+        whitelistDbHandler.addContact(number);
+        contacts.add(number);
+        listviewAdapter.notifyDataSetChanged();
+    }
+}

src/app/src/main/java/com/xfarrow/locatemydevice/WhitelistDbHandler.java

@@ -0,0 +1,83 @@
+package com.xfarrow.locatemydevice;
+
+import android.content.ContentValues;
+import android.content.Context;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteOpenHelper;
+
+import androidx.annotation.Nullable;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class WhitelistDbHandler extends SQLiteOpenHelper {
+
+    private static final int DATABASE_VERSION = 1;
+    private static final String DATABASE_NAME = "WhitelistDb";
+    private static final String TABLE_CONTACTS = "Contacts";
+    private static final String KEY_ID = "id";
+    private static final String KEY_PH_NO = "phone_number";
+
+    public WhitelistDbHandler(@Nullable Context context) {
+        super(context, DATABASE_NAME, null, DATABASE_VERSION);
+    }
+
+    @Override
+    public void onCreate(SQLiteDatabase db) {
+        String CREATE_CONTACTS_TABLE = "CREATE TABLE " + TABLE_CONTACTS + "("
+                + KEY_ID + " " + "INTEGER PRIMARY KEY,"
+                + KEY_PH_NO + " " +  "TEXT" + ")";
+        db.execSQL(CREATE_CONTACTS_TABLE);
+    }
+
+    @Override
+    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
+        db.execSQL("DROP TABLE IF EXISTS " + TABLE_CONTACTS);
+        onCreate(db);
+    }
+
+    // Add a contact
+    void addContact(String phoneNo){
+        SQLiteDatabase db = this.getWritableDatabase();
+        ContentValues values = new ContentValues();
+        values.put(KEY_PH_NO, phoneNo); // Contact Phone
+        db.insert(TABLE_CONTACTS, null, values);
+        db.close(); // Closing database connection
+    }
+
+    // Deleting single contact
+    public void deleteContact(String phoneNo) {
+        SQLiteDatabase db = this.getWritableDatabase();
+        db.delete(TABLE_CONTACTS, KEY_ID + " = ?", new String[] { phoneNo });
+        db.close();
+    }
+
+    public ArrayList<String> getAllContacts() {
+        ArrayList<String> array_list = new ArrayList<String>();
+
+        //hp = new HashMap();
+        SQLiteDatabase db = this.getReadableDatabase();
+        Cursor cursor =  db.rawQuery( "select * from " + TABLE_CONTACTS, null );
+        cursor.moveToFirst();
+
+        int columnIndex = cursor.getColumnIndex(KEY_PH_NO);
+
+        while(!cursor.isAfterLast()){
+            array_list.add(cursor.getString(columnIndex));
+            cursor.moveToNext();
+        }
+        cursor.close();
+        return array_list;
+    }
+
+    public boolean isContactPresent(String phoneNo){
+        SQLiteDatabase db = this.getWritableDatabase();
+        String query = "Select * from " + TABLE_CONTACTS + " where " + KEY_PH_NO + " = " + "\"" + phoneNo + "\"";
+        Cursor cursor = db.rawQuery(query, null);
+        int count = cursor.getCount();
+        cursor.close();
+        return count > 0;
+    }
+
+}

src/app/src/main/res/layout/activity_whitelist_contacts.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".WhitelistContactsActivity">
+
+    <ListView
+        android:id="@+id/ContactsListView"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent"
+        android:divider="#AAAAAA"
+        android:dividerHeight="1dp"/>
+
+</androidx.constraintlayout.widget.ConstraintLayout>

src/app/src/main/res/layout/settings.xml

@@ -60,11 +60,48 @@
             <EditText
                 android:id="@+id/editTextLmdCommand"
                 android:layout_width="match_parent"
-                android:layout_height="wrap_content"
+                android:layout_height="50dp"
                 android:ems="10"
                 android:layout_marginStart="10dp"
                 android:layout_marginEnd="10dp"
                 android:text="LMD" />
+
+            <View
+                android:layout_width="match_parent"
+                android:layout_height="1dp"
+                android:background="?android:attr/listDivider" />
+
+            <TextView
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:textStyle="bold"
+                android:textSize="17sp"
+                android:layout_marginStart="10dp"
+                android:layout_marginTop="10dp"
+                android:text="Whitelist" />
+
+            <Switch
+                android:id="@+id/SwitchWhitelist"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="Enabled"
+                android:layout_marginStart="10dp"
+                tools:ignore="UseSwitchCompatOrMaterialXml" />
+
+            <TextView
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginStart="10dp"
+                android:text="Only contacts in the whitelist are allowed to communicate with this smartphone"/>
+
+            <Button
+                android:id="@+id/buttonAddContacts"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginStart="10dp"
+                android:layout_marginEnd="10dp"
+                android:text="Add contacts"/>
+
         </LinearLayout>
     </ScrollView>
 

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

@@ -0,0 +1,9 @@
+<menu xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+    <item
+        android:id="@+id/add_button"
+        android:title=""
+        app:showAsAction="always"
+        android:icon="@drawable/add"
+        />
+</menu>