/**
   * Открытие слушающего сокета для входящих соединений.
   * 
   * @param port - слушаемый порт.
   */
  protected ServerSocket openListenSocket(int port) throws IOException {
    SSLContext ctx = getContext();
    String bindIp = config.getParam("bindIp");
    ServerSocket socket;
    if ("*".equals(bindIp)) {
      socket = ctx.getServerSocketFactory().createServerSocket(port);
    } else {
      socket = ctx.getServerSocketFactory().createServerSocket(
        port, 10000, InetAddress.getByName(config.getParam("bindIp")));
    }
    ((SSLServerSocket) socket).setNeedClientAuth(true);
    ((SSLServerSocket) socket).setPerformancePreferences(2, 1, 0);
    return socket;
  }

  /**
   * Инициализация ssl-контекста для ГОСТ и RSA,
   * 
   * @return SSLContext контекст соединения
   * @throws IOException при ошибке
   */
  public SSLContext getContext() throws IOException {
    try {
      KeyManagerFactory kmf = null;
      TrustManagerFactory tmf = null;
      KeyStore ts = null;
      String sslContext = config.getParam("sslContext");
      if ("GostTLS".equals(sslContext)) {
        KeyStore ks = KeyStore.getInstance("HDImageStore");
        ks.load(null, null);
        kmf = KeyManagerFactory.getInstance("GostX509");
        kmf.init(ks, config.getParam("keyStorePassword").toCharArray());
        ts = KeyStore.getInstance("HDImageStore");
        tmf = TrustManagerFactory.getInstance("GostX509");
      } else {
        FileInputStream ksStream = null;
        try {
          KeyStore ks = KeyStore.getInstance("JKS");
          ksStream = new FileInputStream(config.getParam("keyStore"));
          ks.load(ksStream, config.getParam("keyStorePassword").toCharArray());
          kmf = KeyManagerFactory.getInstance("SunX509");
          kmf.init(ks, config.getParam("keyStorePassword").toCharArray());
        } finally {
          IOUtils.closeQuietly(ksStream);
        }
        ts = KeyStore.getInstance("JKS");
        tmf = TrustManagerFactory.getInstance("SunX509");
      }
      FileInputStream tsFile = null;
      try {
        tsFile = new FileInputStream(config.getParam("trustStore"));
        ts.load(tsFile, config.getParam("trustStorePassword").toCharArray());
        tmf.init(ts);
      } finally {
        IOUtils.closeQuietly(tsFile);
      }
      SSLContext ctx = SSLContext.getInstance(sslContext);
      ctx.init(kmf.getKeyManagers(), tmf.getTrustManagers(), null);
      return ctx;
    } catch (IOException e) {
      throw new IOException(e.getMessage(), e);
    } catch (GeneralSecurityException e) {
      throw new IOException(e.getMessage(), e);
    }
  }