Proxy configurators

src/org/adblockplus/android/ProxyService.java

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2014 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 package org.adblockplus.android;
 
-import java.io.File;
-import java.io.FileNotFoundException;
 import java.io.IOException;
-import java.lang.reflect.Method;
 import java.net.InetAddress;
 import java.net.ServerSocket;
-import java.util.List;
+import java.net.UnknownHostException;
 import java.util.Properties;
-import java.util.concurrent.TimeoutException;
+
+import org.adblockplus.android.configurators.ProxyConfigurator;
+import org.adblockplus.android.configurators.ProxyConfigurators;
+import org.adblockplus.android.configurators.ProxyRegistrationType;
+import org.apache.commons.lang.StringUtils;
 
 import sunlabs.brazil.server.Server;
 import sunlabs.brazil.util.Base64;
 import android.annotation.SuppressLint;
 import android.app.Notification;
 import android.app.NotificationManager;
 import android.app.PendingIntent;
 import android.app.Service;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.SharedPreferences;
 import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
-import android.content.pm.PackageManager.NameNotFoundException;
-import android.content.res.Resources;
-import android.net.ConnectivityManager;
-import android.net.NetworkInfo;
-import android.net.Proxy;
 import android.os.Binder;
 import android.os.Build;
-import android.os.Handler;
 import android.os.IBinder;
 import android.os.StrictMode;
 import android.preference.PreferenceManager;
 import android.support.v4.app.NotificationCompat;
 import android.util.Log;
 
-import com.stericson.RootTools.RootTools;
-import com.stericson.RootTools.RootToolsException;
-
 public class ProxyService extends Service implements OnSharedPreferenceChangeListener
 {
+  private static final String TAG = Utils.getTag(ProxyService.class);
+
   private static final String LOCALHOST = "127.0.0.1";
-  /**
-   * Indicates that system supports native proxy configuration.
-   */
-  public static final boolean NATIVE_PROXY_SUPPORTED = Build.VERSION.SDK_INT >= 12; // Honeycomb 3.1
 
-  static
-  {
-    RootTools.debugMode = false;
-  }
+  private static final int[] PORT_VARIANTS = new int[] {-1, 2020, 3030, 4040, 5050, 6060, 7070, 9090, 1234, 12345, 4321, 0};
 
-  private static final String TAG = Utils.getTag(ProxyService.class);
-  private static final boolean logRequests = false;
-
-  // Do not use 8080 because it is a "dirty" port, Android uses it if something goes wrong
-  // first element is reserved for previously used port
-  private static final int[] portVariants = new int[] {-1, 2020, 3030, 4040, 5050, 6060, 7070, 9090, 1234, 12345, 4321, 0};
-
-  private static final int DEFAULT_TIMEOUT = 3000;
-  private static final int NO_TRAFFIC_TIMEOUT = 5 * 60 * 1000; // 5 minutes
+  private static final boolean LOG_REQUESTS = false;
 
   static final int ONGOING_NOTIFICATION_ID = R.string.app_name;
+
   private static final long POSITION_RIGHT = Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD ? Long.MIN_VALUE : Long.MAX_VALUE;
-  private static final int NOTRAFFIC_NOTIFICATION_ID = R.string.app_name + 3;
 
   /**
    * Broadcasted when service starts or stops.
    */
-  public static final String BROADCAST_STATE_CHANGED = "org.adblockplus.android.service.state";
+  public static final String BROADCAST_STATE_CHANGED = "org.adblockplus.android.SERVICE_STATE_CHANGED";
+
   /**
    * Broadcasted if proxy fails to start.
    */
-  public static final String BROADCAST_PROXY_FAILED = "org.adblockplus.android.proxy.failure";
+  public static final String BROADCAST_PROXY_FAILED = "org.adblockplus.android.PROXY_FAILURE";
 
-  private static final String IPTABLES_RETURN = " -t nat -m owner --uid-owner {{UID}} -A OUTPUT -p tcp -j RETURN\n";
-  private static final String IPTABLES_ADD_HTTP = " -t nat -A OUTPUT -p tcp --dport 80 -j REDIRECT --to {{PORT}}\n";
+  /**
+   * Common command bridge
+   */
+  public static final String PROXY_STATE_CHANGED_ACTION = "org.adblockplus.android.PROXY_STATE_CHANGED";
 
   boolean hideIcon;
-  private Handler notrafficHandler;
 
   protected ProxyServer proxy = null;
+
   protected int port;
+
   private final Properties proxyConfiguration = new Properties();
 
-  /**
-   * Indicates that service is working with root privileges.
-   */
-  private boolean transparent = false;
-  /**
-   * Indicates that service has autoconfigured Android proxy settings (version 3.1+).
-   */
-  private boolean nativeProxyAutoConfigured = false;
-  /**
-   * Indicates that Android proxy settings are correctly configured (version 4.1.2+ 4.2.2+).
-   */
-  private boolean proxyManualyConfigured = false;
-
-  private String iptables = null;
+  private ProxyConfigurator proxyConfigurator = null;
 
   @SuppressLint("NewApi")
   @Override
   public void onCreate()
   {
     super.onCreate();
 
-    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD)
-    {
-      // Proxy is running in separate thread, it's just some resolution request during initialization.
-      // Not worth spawning a separate thread for this.
-      final StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitNetwork().build();
-      StrictMode.setThreadPolicy(policy);
-    }
+    StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder()
+        .permitAll()
+        .penaltyLog()
+        .build());
 
-    // Get port for local proxy
     final SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
-    final Resources resources = getResources();
 
     // Try to read user proxy settings
-    String proxyHost = null;
-    String proxyPort = null;
-    String proxyExcl = null;
+    String proxyHost = System.getProperty("http.proxyHost");;
+    String proxyPort = System.getProperty("http.proxyPort");
+    final String proxyExcl = System.getProperty("http.nonProxyHosts");
     String proxyUser = null;
     String proxyPass = null;
 
-    if (NATIVE_PROXY_SUPPORTED)
-    {
-      // Read system settings
-      proxyHost = System.getProperty("http.proxyHost");
-      proxyPort = System.getProperty("http.proxyPort");
-      proxyExcl = System.getProperty("http.nonProxyHosts");
-
-      Log.d(TAG, "PRX: " + proxyHost + ":" + proxyPort + "(" + proxyExcl + ")");
-      // not used but left for future reference
-      final String[] px = ProxySettings.getUserProxy(getApplicationContext());
-      if (px != null)
-        Log.d(TAG, "PRX: " + px[0] + ":" + px[1] + "(" + px[2] + ")");
-    }
-    else
+    if (proxyHost == null || proxyPort == null)
     {
       // Read application settings
       proxyHost = prefs.getString(getString(R.string.pref_proxyhost), null);
       proxyPort = prefs.getString(getString(R.string.pref_proxyport), null);
       proxyUser = prefs.getString(getString(R.string.pref_proxyuser), null);
       proxyPass = prefs.getString(getString(R.string.pref_proxypass), null);
     }
 
-    // Check for root privileges and try to install transparent proxy
-    if (RootTools.isAccessGiven())
+    registerReceiver(this.proxyReceiver, new IntentFilter(ProxyService.BROADCAST_PROXY_FAILED));
+    registerReceiver(this.proxyStateChangedReceiver, new IntentFilter(ProxyService.PROXY_STATE_CHANGED_ACTION));
+
+    final InetAddress inetAddress;
+    try
     {
-      try
-      {
-        initIptables();
-
-        final StringBuffer cmd = new StringBuffer();
-        final int uid = getPackageManager().getPackageInfo(getPackageName(), 0).applicationInfo.uid;
-        cmd.append(iptables);
-        cmd.append(IPTABLES_RETURN.replace("{{UID}}", String.valueOf(uid)));
-        final String rules = cmd.toString();
-        RootTools.sendShell(rules, DEFAULT_TIMEOUT);
-        transparent = true;
-      }
-      catch (final FileNotFoundException e)
-      {
-        // ignore - this is "normal" case
-      }
-      catch (final NameNotFoundException e)
-      {
-        Log.e(TAG, "Failed to initialize iptables", e);
-      }
-      catch (final IOException e)
-      {
-        Log.e(TAG, "Failed to initialize iptables", e);
-      }
-      catch (final RootToolsException e)
-      {
-        Log.e(TAG, "Failed to initialize iptables", e);
-      }
-      catch (final TimeoutException e)
-      {
-        Log.e(TAG, "Failed to initialize iptables", e);
-      }
+      inetAddress = InetAddress.getByName(LOCALHOST);
     }
-
-    if (!transparent)
+    catch (final UnknownHostException e)
     {
-      // Try to set native proxy
-      nativeProxyAutoConfigured = ProxySettings.setConnectionProxy(getApplicationContext(), LOCALHOST, port, "");
-
-      if (NATIVE_PROXY_SUPPORTED)
-      {
-        registerReceiver(connectionReceiver, new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION));
-        registerReceiver(connectionReceiver, new IntentFilter(Proxy.PROXY_CHANGE_ACTION));
-      }
+      sendBroadcast(new Intent(BROADCAST_PROXY_FAILED)
+          .putExtra("msg", "Could not resolve 'localhost'"));
+      return;
     }
 
-    // Save current native proxy situation. The service is always started on the first run so
-    // we will always have a correct value from the box
-    final SharedPreferences.Editor editor = prefs.edit();
-    editor.putBoolean(getString(R.string.pref_proxyautoconfigured), transparent || nativeProxyAutoConfigured);
-    editor.commit();
-
-    registerReceiver(proxyReceiver, new IntentFilter(ProxyService.BROADCAST_PROXY_FAILED));
-    registerReceiver(filterReceiver, new IntentFilter(AdblockPlus.BROADCAST_FILTERING_CHANGE));
-    registerReceiver(filterReceiver, new IntentFilter(AdblockPlus.BROADCAST_FILTER_MATCHES));
-
     // Start proxy
     if (proxy == null)
     {
       // Select available port and bind to it, use previously selected port by default
-      portVariants[0] = prefs.getInt(getString(R.string.pref_lastport), -1);
       ServerSocket listen = null;
       String msg = null;
-      for (final int p : portVariants)
+      for (final int p : PORT_VARIANTS)
       {
-        if (p < 0)
-          continue;
-        try
+        final int toCheck = (p == -1) ? prefs.getInt(getString(R.string.pref_lastport), -1) : p;
+
+        if (toCheck >= 0)
         {
-          // Fix for #232, bind proxy socket to loopback only
-          listen = new ServerSocket(p, 1024, InetAddress.getByName(LOCALHOST));
-          port = p;
-          break;
-        }
-        catch (final IOException e)
-        {
-          Log.e(TAG, null, e);
-          msg = e.getMessage();
+          try
+          {
+            // Fix for #232, bind proxy socket to loopback only
+            listen = new ServerSocket(toCheck, 1024, inetAddress);
+            this.port = listen.getLocalPort();
+            break;
+          }
+          catch (final IOException e)
+          {
+            Log.e(TAG, null, e);
+            msg = e.getMessage();
+          }
         }
       }
+
       if (listen == null)
       {
         sendBroadcast(new Intent(BROADCAST_PROXY_FAILED).putExtra("msg", msg));
         return;
       }
 
+      this.proxyConfigurator = ProxyConfigurators.registerProxy(this, inetAddress, this.port);
+
+      if (this.proxyConfigurator == null)
+      {
+        sendBroadcast(new Intent(BROADCAST_PROXY_FAILED)
+            .putExtra("msg", "Failed to register proxy"));
+        return;
+      }
+
       // Save selected port
+      final SharedPreferences.Editor editor = prefs.edit();
+      editor.putBoolean(getString(R.string.pref_proxyautoconfigured), this.getProxyRegistrationType().isAutoConfigured());
       editor.putInt(getString(R.string.pref_lastport), port);
       editor.commit();
 
       // Initialize proxy
       proxyConfiguration.put("handler", "main");
       proxyConfiguration.put("main.prefix", "");
       proxyConfiguration.put("main.class", "sunlabs.brazil.server.ChainHandler");
-      if (transparent)
+      switch (this.getProxyRegistrationType().getProxyType())
       {
+      case HTTP:
         proxyConfiguration.put("main.handlers", "urlmodifier adblock");
         proxyConfiguration.put("urlmodifier.class", "org.adblockplus.brazil.TransparentProxyHandler");
-      }
-      else
-      {
+        break;
+      case HTTPS:
         proxyConfiguration.put("main.handlers", "https adblock");
         proxyConfiguration.put("https.class", "org.adblockplus.brazil.SSLConnectionHandler");
+        break;
+      default:
+        sendBroadcast(new Intent(BROADCAST_PROXY_FAILED)
+            .putExtra("msg", "Unsupported proxy server type: " + this.getProxyRegistrationType().getProxyType()));
+        return;
       }
       proxyConfiguration.put("adblock.class", "org.adblockplus.brazil.RequestHandler");
-      if (logRequests)
+      if (LOG_REQUESTS)
         proxyConfiguration.put("adblock.proxylog", "yes");
 
       configureUserProxy(proxyConfiguration, proxyHost, proxyPort, proxyExcl, proxyUser, proxyPass);
 
       proxy = new ProxyServer();
-      proxy.logLevel = Server.LOG_DIAGNOSTIC;
+      proxy.logLevel = Server.LOG_LOG;
       proxy.setup(listen, proxyConfiguration.getProperty("handler"), proxyConfiguration);
       proxy.start();
     }
 
-    if (transparent)
-    {
-      // Redirect traffic via iptables
-      try
-      {
-        final StringBuffer cmd = new StringBuffer();
-        cmd.append(iptables);
-        cmd.append(IPTABLES_ADD_HTTP.replace("{{PORT}}", String.valueOf(port)));
-        final String rules = cmd.toString();
-        RootTools.sendShell(rules, DEFAULT_TIMEOUT);
-      }
-      catch (final FileNotFoundException e)
-      {
-        // ignore - this is "normal" case
-      }
-      catch (final IOException e)
-      {
-        Log.e(TAG, "Failed to initialize iptables", e);
-      }
-      catch (final RootToolsException e)
-      {
-        Log.e(TAG, "Failed to initialize iptables", e);
-      }
-      catch (final TimeoutException e)
-      {
-        Log.e(TAG, "Failed to initialize iptables", e);
-      }
-    }
-
     prefs.registerOnSharedPreferenceChangeListener(this);
 
     // Lock service
-    hideIcon = prefs.getBoolean(getString(R.string.pref_hideicon), resources.getBoolean(R.bool.def_hideicon));
+    hideIcon = prefs.getBoolean(getString(R.string.pref_hideicon), getResources().getBoolean(R.bool.def_hideicon));
     startForeground(ONGOING_NOTIFICATION_ID, getNotification());
 
-    // If automatic setting of proxy was blocked, check if user has set it manually
-    final boolean manual = isManual();
-    if (manual && NATIVE_PROXY_SUPPORTED)
-    {
-      final ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
-      updateNoTrafficCheck(connectivityManager);
-    }
-
     sendStateChangedBroadcast();
     Log.i(TAG, "Service started");
   }
 
   @Override
   public int onStartCommand(final Intent intent, final int flags, final int startId)
   {
     return START_STICKY;
   }
 
   @Override
   public void onDestroy()
   {
     super.onDestroy();
 
-    stopNoTrafficCheck();
+    unregisterReceiver(this.proxyReceiver);
+    unregisterReceiver(this.proxyStateChangedReceiver);
 
-    unregisterReceiver(filterReceiver);
-    unregisterReceiver(proxyReceiver);
-
-    // Stop IP redirecting
-    if (transparent)
+    if (this.proxyConfigurator != null)
     {
-      new Thread()
-      {
-        @Override
-        public void run()
-        {
-          try
-          {
-            RootTools.sendShell(iptables + " -t nat -F OUTPUT", DEFAULT_TIMEOUT);
-          }
-          catch (final Exception e)
-          {
-            Log.e(TAG, "Failed to clear iptables", e);
-          }
-        }
-      }.start();
-    }
-
-    if (!transparent && NATIVE_PROXY_SUPPORTED)
-      unregisterReceiver(connectionReceiver);
-
-    // Clear native proxy
-    if (nativeProxyAutoConfigured)
-    {
-      clearConnectionProxy();
+      this.proxyConfigurator.unregisterProxy();
+      this.proxyConfigurator.shutdown();
     }
 
     sendBroadcast(new Intent(BROADCAST_STATE_CHANGED).putExtra("enabled", false));
 
     // Stop proxy server
     if (proxy != null)
+    {
       proxy.close();
+      proxy = null;
+    }
 
     // Release service lock
     stopForeground(true);
 
     Log.i(TAG, "Service stopped");
   }
 
   /**
-   * Restores system proxy settings via native call on Android 3.1+ devices
-   * using Java reflection.
-   */
-  private void clearConnectionProxy()
-  {
-    final String proxyHost = proxyConfiguration.getProperty("adblock.proxyHost");
-    final String proxyPort = proxyConfiguration.getProperty("adblock.proxyPort");
-    final String proxyExcl = proxyConfiguration.getProperty("adblock.proxyExcl");
-    int port = 0;
-    try
-    {
-      if (proxyHost != null)
-        port = Integer.valueOf(proxyPort);
-    }
-    catch (final NumberFormatException e)
-    {
-      Log.e(TAG, "Bad port setting", e);
-    }
-    ProxySettings.setConnectionProxy(getApplicationContext(), proxyHost, port, proxyExcl);
-  }
-
-  /**
    * Sets user proxy settings in proxy service properties.
    */
-  private void configureUserProxy(final Properties config, final String proxyHost, final String proxyPort, final String proxyExcl, final String proxyUser, final String proxyPass)
+  private void configureUserProxy(final Properties config, final String proxyHost, final String proxyPort, final String proxyExcl,
+      final String proxyUser, final String proxyPass)
   {
     // Clean previous settings
     config.remove("adblock.proxyHost");
     config.remove("adblock.proxyPort");
     config.remove("adblock.auth");
     config.remove("adblock.proxyExcl");
-    if (!transparent)
+    config.remove("https.proxyHost");
+    config.remove("https.proxyPort");
+    config.remove("https.auth");
+
+    final ProxyRegistrationType regType = this.getProxyRegistrationType();
+    if (regType == ProxyRegistrationType.NATIVE)
     {
-      config.remove("https.proxyHost");
-      config.remove("https.proxyPort");
-      config.remove("https.auth");
+      passProxySettings(proxyHost, proxyPort, proxyExcl);
     }
 
-    if (nativeProxyAutoConfigured)
-      passProxySettings(proxyHost, proxyPort, proxyExcl);
-
     // Check if there are any settings
-    if (proxyHost == null || "".equals(proxyHost))
+    if (StringUtils.isEmpty(proxyHost))
+    {
       return;
+    }
 
     // Check for dirty proxy settings - this indicated previous crash:
     // proxy points to ourselves
     // proxy port is null, 0 or not a number
     // proxy is 127.0.0.1:8080
     if (proxyPort == null)
+    {
       return;
-    int p = 0;
+    }
+
+    final int p;
     try
     {
       p = Integer.valueOf(proxyPort);
     }
     catch (final NumberFormatException e)
     {
       return;
     }
-    if (p == 0 || isLocalHost(proxyHost) && (p == port || p == 8080))
+
+    if (p == 0 || isLocalhost(proxyHost) && (p == port || p == 8080))
     {
-      if (nativeProxyAutoConfigured)
+      if (regType == ProxyRegistrationType.NATIVE)
+      {
         passProxySettings(null, null, null);
+      }
       return;
     }
 
     config.put("adblock.proxyHost", proxyHost);
     config.put("adblock.proxyPort", proxyPort);
-    if (!transparent)
+    if (regType.getProxyType() == ProxyServerType.HTTPS)
     {
       config.put("https.proxyHost", proxyHost);
       config.put("https.proxyPort", proxyPort);
     }
 
     // TODO Not implemented in our proxy but needed to restore settings
     if (proxyExcl != null)
+    {
       config.put("adblock.proxyExcl", proxyExcl);
+    }
 
-    if (proxyUser != null && !"".equals(proxyUser) && proxyPass != null && !"".equals(proxyPass))
+    if (StringUtils.isNotEmpty(proxyUser) && StringUtils.isNotEmpty(proxyPass))
     {
       // Base64 encode user:password
       final String proxyAuth = "Basic " + new String(Base64.encode(proxyUser + ":" + proxyPass));
       config.put("adblock.auth", proxyAuth);
-      if (!transparent)
+      if (regType.getProxyType() == ProxyServerType.HTTPS)
+      {
         config.put("https.auth", proxyAuth);
+      }
     }
   }
 
+  /**
+   * @return {@code true} if the given host string resolves to {@code localhost}
+   */
+  public static boolean isLocalhost(final String host)
+  {
+    try
+    {
+      if (StringUtils.isEmpty(host))
+      {
+        return false;
+      }
+
+      if (host.equals("127.0.0.1") || host.equalsIgnoreCase("localhost"))
+      {
+        return true;
+      }
+
+      return InetAddress.getByName(host).isLoopbackAddress();
+    }
+    catch (final Exception e)
+    {
+      return false;
+    }
+  }
+
   private void passProxySettings(final String proxyHost, final String proxyPort, final String proxyExcl)
   {
     try
     {
       final CrashHandler handler = (CrashHandler) Thread.getDefaultUncaughtExceptionHandler();
       handler.saveProxySettings(proxyHost, proxyPort, proxyExcl);
     }
     catch (final ClassCastException e)
     {
       // ignore - default handler in use
     }
   }
 
   @Override
   public void onSharedPreferenceChanged(final SharedPreferences sharedPreferences, final String key)
   {
-    if (!NATIVE_PROXY_SUPPORTED)
+    // TODO verify this

[Felix Dahlke, 2014/08/24 11:51:19]

Can we remove the TODO or turn it into an issue?

[René Jeschke, 2014/08/24 11:54:14]

Done.

+    if (this.getProxyRegistrationType() != ProxyRegistrationType.NATIVE)
     {
-      final String ketHost = getString(R.string.pref_proxyhost);
+      final String keyHost = getString(R.string.pref_proxyhost);
       final String keyPort = getString(R.string.pref_proxyport);
       final String keyUser = getString(R.string.pref_proxyuser);
       final String keyPass = getString(R.string.pref_proxypass);
-      if (key.equals(ketHost) || key.equals(keyPort) || key.equals(keyUser) || key.equals(keyPass))
+      if (key.equals(keyHost) || key.equals(keyPort) || key.equals(keyUser) || key.equals(keyPass))
       {
-        final String proxyHost = sharedPreferences.getString(ketHost, null);
+        final String proxyHost = sharedPreferences.getString(keyHost, null);
         final String proxyPort = sharedPreferences.getString(keyPort, null);
         final String proxyUser = sharedPreferences.getString(keyUser, null);
         final String proxyPass = sharedPreferences.getString(keyPass, null);
         if (proxy != null)
         {
           configureUserProxy(proxyConfiguration, proxyHost, proxyPort, null, proxyUser, proxyPass);
           proxy.restart(proxyConfiguration.getProperty("handler"));
         }
       }
     }
   }
 
-  public boolean isTransparent()
-  {
-    return transparent;
-  }
-
-  public boolean isNativeProxyAutoConfigured()
-  {
-    return nativeProxyAutoConfigured;
-  }
-
-  /**
-   * Checks if user has to set proxy settings manually
-   */
-  public boolean isManual()
-  {
-    return !transparent && !nativeProxyAutoConfigured;
-  }
-
-  /**
-   * Checks whether traffic check is pending
-   */
-  public boolean noTraffic()
-  {
-    return notrafficHandler != null;
-  }
-
-  /**
-   * Checks if specified host is local.
-   */
-  private static final boolean isLocalHost(final String host)
-  {
-    if (host == null)
-      return false;
-
-    try
-    {
-      if (host.equalsIgnoreCase("localhost"))
-        return true;
-
-      final String className = "android.net.NetworkUtils";
-      final Class<?> c = Class.forName(className);
-      /*
-       * InetAddress address = NetworkUtils.numericToInetAddress(host);
-       */
-      final Method method = c.getMethod("numericToInetAddress", String.class);
-      final InetAddress address = (InetAddress) method.invoke(null, host);
-
-      if (address.isLoopbackAddress())
-        return true;
-    }
-    catch (final Exception e)
-    {
-      Log.w(TAG, null, e);
-    }
-    return false;
-  }
-
-  /**
-   * Initializes iptables executable.
-   *
-   * @throws FileNotFoundException
-   *           If iptables initialization failed due to provided reasons.
-   */
-  private void initIptables() throws IOException, RootToolsException, TimeoutException, FileNotFoundException
-  {
-    if (!RootTools.isAccessGiven())
-      throw new FileNotFoundException("No root access");
-
-    final File ipt = getFileStreamPath("iptables");
-
-    if (!ipt.exists())
-    {
-      Log.e(TAG, "No iptables excutable found");
-      throw new FileNotFoundException("No iptables executable");
-    }
-
-    final String path = ipt.getAbsolutePath();
-
-    RootTools.sendShell("chmod 700 " + path, DEFAULT_TIMEOUT);
-
-    boolean compatible = false;
-    boolean version = false;
-
-    final String command = path + " --version\n" + path + " -L -t nat -n\n";
-
-    final List<String> result = RootTools.sendShell(command, DEFAULT_TIMEOUT);
-    for (final String line : result)
-    {
-      if (line.contains("OUTPUT"))
-        compatible = true;
-      if (line.contains("v1.4."))
-        version = true;
-    }
-
-    if (!compatible || !version)
-    {
-      Log.e(TAG, "Incompatible iptables excutable");
-      throw new FileNotFoundException("Incompatible iptables excutable");
-    }
-
-    iptables = path;
-  }
-
-  public List<String> getIptablesOutput()
-  {
-    if (iptables == null)
-      return null;
-
-    final String command = iptables + " -L -t nat -n\n";
-    try
-    {
-      return RootTools.sendShell(command, DEFAULT_TIMEOUT);
-    }
-    catch (final Exception e)
-    {
-      Log.e(TAG, "Failed to get iptables configuration", e);
-      return null;
-    }
-  }
-
   /**
-   * Raises or removes no traffic notification based on current link proxy
-   * settings
+   * @return the active proxy configuration's type or {@link ProxyRegistrationType#UNKNOWN} if none is configured
    */
-  private void updateNoTrafficCheck(final ConnectivityManager connectivityManager)
+  private ProxyRegistrationType getProxyRegistrationType()
   {
-    try
-    {
-      final Object pp = ProxySettings.getActiveLinkProxy(connectivityManager);
-      final String[] userProxy = ProxySettings.getUserProxy(pp);
-      if (userProxy != null)
-        Log.i(TAG, "Proxy settings: " + userProxy[0] + ":" + userProxy[1] + "(" + userProxy[2] + ")");
-      updateNoTrafficCheck(userProxy);
-    }
-    catch (final Exception e)
-    {
-      // This should not happen
-      Log.e(TAG, null, e);
-    }
+    return this.proxyConfigurator != null ? this.proxyConfigurator.getType() : ProxyRegistrationType.UNKNOWN;
   }
 
   /**
-   * Raises or removes no traffic notification based on the user proxy settings
+   * @return {@code true} if there is a valid proxy configurator and registration succeeded
    */
-  private void updateNoTrafficCheck(final String[] userProxy)
+  public boolean isRegistered()
   {
-    final boolean ourProxy = userProxy != null && isLocalHost(userProxy[0]) && Integer.valueOf(userProxy[1]) == port;
-    if (ourProxy != proxyManualyConfigured)
-    {
-      proxyManualyConfigured = ourProxy;
-      sendStateChangedBroadcast();
-    }
-    if (ourProxy)
-    {
-      stopNoTrafficCheck();
-    }
-    else
-    {
-      // Initiate no traffic check
-      notrafficHandler = new Handler();
-      notrafficHandler.postDelayed(noTraffic, NO_TRAFFIC_TIMEOUT);
-    }
-    final NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
-    notificationManager.notify(ONGOING_NOTIFICATION_ID, getNotification());
+    return this.proxyConfigurator != null && this.proxyConfigurator.isRegistered();
   }
 
   /**
-   * Stops no traffic check and resets notification message.
+   * @return {@code true} if registration type is {@link ProxyRegistrationType#NATIVE} and registration succeeded
    */
-  private void stopNoTrafficCheck()
+  public boolean isNativeProxyAutoConfigured()
   {
-    if (notrafficHandler != null)
-    {
-      notrafficHandler.removeCallbacks(noTraffic);
-      sendStateChangedBroadcast();
-      final NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
-      notificationManager.notify(ONGOING_NOTIFICATION_ID, getNotification());
-      notificationManager.cancel(NOTRAFFIC_NOTIFICATION_ID);
-    }
-    notrafficHandler = null;
+    return this.getProxyRegistrationType() == ProxyRegistrationType.NATIVE && this.isRegistered();
+  }
+
+  /**
+   * @return {@code true} if registration type is {@link ProxyRegistrationType#MANUAL}
+   */
+  public boolean isManual()
+  {
+    return this.getProxyRegistrationType() == ProxyRegistrationType.MANUAL;
+  }
+
+  /**
+   * @return {@code true} if registration type is {@link ProxyRegistrationType#IPTABLES}
+   */
+  public boolean isIptables()
+  {
+    return this.getProxyRegistrationType() == ProxyRegistrationType.IPTABLES;
   }
 
   @SuppressLint("NewApi")
   private Notification getNotification()
   {
     final boolean filtering = AdblockPlus.getApplication().isFilteringEnabled();
 
-    int msgId = R.string.notif_waiting;
-    if (nativeProxyAutoConfigured || proxyManualyConfigured)
+    final int msgId;
+    switch(this.getProxyRegistrationType())
+    {
+    case MANUAL:
+      if (this.isRegistered())
+      {
+        msgId = filtering ? R.string.notif_wifi : R.string.notif_wifi_nofiltering;
+      }
+      else
+      {
+        msgId = filtering ? R.string.notif_waiting : R.string.notif_wifi_nofiltering;
+      }
+      break;
+    case NATIVE:
       msgId = filtering ? R.string.notif_wifi : R.string.notif_wifi_nofiltering;
-    if (transparent)
+      break;
+    case IPTABLES:
+    case CYANOGENMOD:
       msgId = R.string.notif_all;
+      break;
+    default:
+      msgId = R.string.notif_waiting;
+      break;
+    }
 
     final NotificationCompat.Builder builder = new NotificationCompat.Builder(this);
     if (hideIcon && msgId != R.string.notif_waiting)
     {
       builder.setWhen(POSITION_RIGHT);
       builder.setSmallIcon(R.drawable.transparent);
-      // builder.setContent(new RemoteViews(getPackageName(), R.layout.notif_hidden));
     }
     else
     {
       builder.setWhen(0);
       builder.setSmallIcon(R.drawable.ic_stat_blocking);
     }
-    final PendingIntent contentIntent = PendingIntent.getActivity(this, 0, new Intent(this, Preferences.class).addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_NEW_TASK), 0);
+    final PendingIntent contentIntent = PendingIntent.getActivity(this, 0,
+        new Intent(this, Preferences.class).addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_NEW_TASK), 0);
+
     builder.setContentIntent(contentIntent);
     builder.setContentTitle(getText(R.string.app_name));
     builder.setContentText(getString(msgId, port));
     builder.setOngoing(true);
 
-    final Notification notification = builder.getNotification();
-    return notification;
+    return builder.getNotification();
   }
 
   public void setEmptyIcon(final boolean hide)
   {
     hideIcon = hide;
     final NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
     notificationManager.notify(ONGOING_NOTIFICATION_ID, getNotification());
   }
 
   public void sendStateChangedBroadcast()
   {
-    Log.i(TAG, "Broadcasting " + BROADCAST_STATE_CHANGED);
     final boolean manual = isManual();
-    final Intent stateIntent = new Intent(BROADCAST_STATE_CHANGED).putExtra("enabled", true).putExtra("port", port).putExtra("manual", manual);
+    final Intent stateIntent = new Intent(BROADCAST_STATE_CHANGED)
+        .putExtra("enabled", true)
+        .putExtra("port", port)
+        .putExtra("manual", manual);
+
     if (manual)
-      stateIntent.putExtra("configured", proxyManualyConfigured);
+    {
+      stateIntent.putExtra("configured", this.isRegistered());
+    }
+
     sendBroadcast(stateIntent);
   }
 
   private final IBinder binder = new LocalBinder();
 
   public final class LocalBinder extends Binder
   {
     public ProxyService getService()
     {
       return ProxyService.this;
     }
   }
 
   @Override
   public IBinder onBind(final Intent intent)
   {
     return binder;
   }
 
   /**
-   * Executed if no traffic is detected after a period of time. Notifies user
-   * about possible configuration problems.
-   */
-  private final Runnable noTraffic = new Runnable()
-  {
-    @Override
-    public void run()
-    {
-      // It's weird but notrafficHandler.removeCallbacks(noTraffic) does not remove this callback
-      if (notrafficHandler == null)
-        return;
-      // Show warning notification
-      final NotificationCompat.Builder builder = new NotificationCompat.Builder(ProxyService.this);
-      builder.setSmallIcon(R.drawable.ic_stat_warning);
-      builder.setWhen(System.currentTimeMillis());
-      builder.setAutoCancel(true);
-      final Intent intent = new Intent(ProxyService.this, ConfigurationActivity.class).addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
-      intent.putExtra("port", port);
-      final PendingIntent contentIntent = PendingIntent.getActivity(ProxyService.this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
-      builder.setContentIntent(contentIntent);
-      builder.setContentTitle(getText(R.string.app_name));
-      builder.setContentText(getText(R.string.notif_notraffic));
-      final NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
-      notificationManager.notify(NOTRAFFIC_NOTIFICATION_ID, builder.getNotification());
-    }
-  };
-
-  /**
-   * Stops no traffic check if traffic is detected by proxy service.
-   */
-  private final BroadcastReceiver filterReceiver = new BroadcastReceiver()
-  {
-    @Override
-    public void onReceive(final Context context, final Intent intent)
-    {
-      if (intent.getAction().equals(AdblockPlus.BROADCAST_FILTERING_CHANGE))
-      {
-        // It's rather a hack but things are happening simultaneously and we
-        // receive this broadcast despite the fact we have unsubscribed from
-        // it and notification is not removed because it is changed to new one
-        // during removal.
-        if (!isNativeProxyAutoConfigured())
-        {
-          final NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
-          notificationManager.notify(ONGOING_NOTIFICATION_ID, getNotification());
-        }
-      }
-      if (intent.getAction().equals(AdblockPlus.BROADCAST_FILTER_MATCHES))
-      {
-        proxyManualyConfigured = true;
-        stopNoTrafficCheck();
-      }
-    }
-  };
-
-  /**
    * Stops service if proxy fails.
    */
   private final BroadcastReceiver proxyReceiver = new BroadcastReceiver()
   {
     @Override
     public void onReceive(final Context context, final Intent intent)
     {
       if (intent.getAction().equals(ProxyService.BROADCAST_PROXY_FAILED))
       {
         stopSelf();
       }
     }
   };
 
   /**
-   * Monitors system network connection settings changes and updates proxy
-   * settings accordingly.
+   * <p>
+   * Proxy state change receiver.
+   * </p>
    */
-  private final BroadcastReceiver connectionReceiver = new BroadcastReceiver()
+  private final BroadcastReceiver proxyStateChangedReceiver = new BroadcastReceiver()
   {
     @Override
-    public void onReceive(final Context ctx, final Intent intent)
+    public void onReceive(final Context context, final Intent intent)
     {
-      final String action = intent.getAction();
-      Log.i(TAG, "Action: " + action);
-      // Connectivity change
-      if (ConnectivityManager.CONNECTIVITY_ACTION.equals(action))
+      if (intent != null && PROXY_STATE_CHANGED_ACTION.equals(intent.getAction()))
       {
-        final ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
-        // TODO Should we use ConnectivityManagerCompat.getNetworkInfoFromBroadcast() instead?
-        final NetworkInfo info = connectivityManager.getActiveNetworkInfo();
-        if (info == null)
-          return;
-        final String typeName = info.getTypeName();
-        final String subtypeName = info.getSubtypeName();
-        final boolean available = info.isAvailable();
-
-        Log.i(TAG, "Network Type: " + typeName + ", subtype: " + subtypeName + ", available: " + available);
-        if (info.getType() == ConnectivityManager.TYPE_WIFI)
-        {
-          if (nativeProxyAutoConfigured)
-          {
-            ProxySettings.setConnectionProxy(getApplicationContext(), LOCALHOST, port, "");
-          }
-          else
-          {
-            updateNoTrafficCheck(connectivityManager);
-          }
-        }
-      }
-      // Proxy change
-      else if (Proxy.PROXY_CHANGE_ACTION.equals(action))
-      {
-        final Object pp = intent.getParcelableExtra("proxy");
-        try
-        {
-          final String[] userProxy = ProxySettings.getUserProxy(pp);
-          if (nativeProxyAutoConfigured)
-          {
-            if (userProxy != null && Integer.valueOf(userProxy[1]) != port)
-            {
-              Log.i(TAG, "User has set new proxy: " + userProxy[0] + ":" + userProxy[1] + "(" + userProxy[2] + ")");
-              if (proxy != null)
-              {
-                configureUserProxy(proxyConfiguration, userProxy[0], userProxy[1], userProxy[2], null, null);
-                proxy.restart(proxyConfiguration.getProperty("handler"));
-              }
-            }
-          }
-          else
-          {
-            Log.i(TAG, "User has set proxy: " + userProxy[0] + ":" + userProxy[1] + "(" + userProxy[2] + ")");
-            updateNoTrafficCheck(userProxy);
-          }
-        }
-        catch (final Exception e)
-        {
-          // This should not happen
-          Log.e(TAG, null, e);
-        }
+        final NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
+        notificationManager.notify(ONGOING_NOTIFICATION_ID, getNotification());
+        ProxyService.this.sendStateChangedBroadcast();
       }
     }
   };
 
   final class ProxyServer extends Server
   {
     @Override
     public void close()
     {
       try
@@ skipping 12 matching lines @@
     @Override
     public void log(final int level, final Object obj, final String message)
     {
       if (level <= logLevel)
       {
         Log.println(7 - level, obj != null ? obj.toString() : TAG, message);
       }
     }
   }
 }