Allow to blacklist numbers in the telephony plugin

Summary:
Depends on D10519

Allow to specify a newline separated list of blocked numbers. This can be useful for 2FA/TAN that could be leaked to the desktop.

The protection is incomplete because the notification might be leaked trough the notificationsplugin anyway (T6651).

Test Plan:
Block my number, send SMS to self -> only notification from Notificationsplugin is shown.
Unblock it again -> both notifications are shown

Reviewers: #kde_connect, albertvaka, mtijink

Reviewed By: #kde_connect, albertvaka, mtijink

Subscribers: mtijink, albertvaka, #kde_connect

Tags: #kde_connect

Differential Revision: https://phabricator.kde.org/D10520

res/values/strings.xml

@@ -217,5 +217,7 @@
     <string name="telephony_permission_explanation">To see phone calls and SMS from the desktop you need to give permission to phone calls and SMS</string>
     <string name="telephony_optional_permission_explanation">To see a contact name instead of a phone number you need to give access to the phone\'s contacts</string>
     <string name="select_ringtone">Select a ringtone</string>
+    <string name="telephony_pref_blocked_title">Blocked numbers</string>
+    <string name="telephony_pref_blocked_dialog_desc">Don\'t show calls and SMS from these numbers. Please specify one number per line</string>
 
 </resources>

res/xml/telephonyplugin_preferences.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <EditTextPreference
+        android:key="telephony_blocked_numbers"
+        android:title="@string/telephony_pref_blocked_title"
+        android:dialogMessage="@string/telephony_pref_blocked_dialog_desc">
+    </EditTextPreference>
+
+</PreferenceScreen>

src/org/kde/kdeconnect/Plugins/TelephonyPlugin/TelephonyPlugin.java

@@ -25,11 +25,14 @@ import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
+import android.content.SharedPreferences;
 import android.content.pm.PackageManager;
 import android.media.AudioManager;
 import android.os.Build;
 import android.os.Bundle;
+import android.preference.PreferenceManager;
 import android.support.v4.content.ContextCompat;
+import android.telephony.PhoneNumberUtils;
 import android.telephony.SmsMessage;
 import android.telephony.TelephonyManager;
 import android.util.Log;
@@ -49,6 +52,7 @@ public class TelephonyPlugin extends Plugin {
 
     private final static String PACKAGE_TYPE_TELEPHONY = "kdeconnect.telephony";
     public final static String PACKAGE_TYPE_TELEPHONY_REQUEST = "kdeconnect.telephony.request";
+    private static final String KEY_PREF_BLOCKED_NUMBERS = "telephony_blocked_numbers";
 
     private int lastState = TelephonyManager.CALL_STATE_IDLE;
     private NetworkPackage lastPackage = null;
@@ -114,6 +118,9 @@ public class TelephonyPlugin extends Plugin {
 
     private void callBroadcastReceived(int state, String phoneNumber) {
 
+        if (isNumberBlocked(phoneNumber))
+            return;
+
         NetworkPackage np = new NetworkPackage(PACKAGE_TYPE_TELEPHONY);
 
         int permissionCheck = ContextCompat.checkSelfPermission(context,
@@ -234,6 +241,9 @@ public class TelephonyPlugin extends Plugin {
 
         String phoneNumber = messages.get(0).getOriginatingAddress();
 
+        if (isNumberBlocked(phoneNumber))
+            return;
+
         int permissionCheck = ContextCompat.checkSelfPermission(context,
                 Manifest.permission.READ_CONTACTS);
 
@@ -289,6 +299,18 @@ public class TelephonyPlugin extends Plugin {
         return true;
     }
 
+    private boolean isNumberBlocked(String number) {
+        SharedPreferences sharedPref = PreferenceManager.getDefaultSharedPreferences(context);
+        String[] blockedNumbers = sharedPref.getString(KEY_PREF_BLOCKED_NUMBERS, "").split("\n");
+
+        for (String s: blockedNumbers) {
+            if (PhoneNumberUtils.compare(number, s))
+                return true;
+        }
+
+        return false;
+    }
+
     @Override
     public String[] getSupportedPackageTypes() {
         return new String[]{PACKAGE_TYPE_TELEPHONY_REQUEST};
@@ -308,4 +330,9 @@ public class TelephonyPlugin extends Plugin {
     public String[] getOptionalPermissions() {
         return new String[]{Manifest.permission.READ_CONTACTS};
     }
+
+    @Override
+    public boolean hasSettings() {
+        return true;
+    }
 }