Beispiel #1
0
  public static byte[] intToNetworkByteOrder(int num, int count) {
    byte[] buf = new byte[count];
    intToNetworkByteOrder(num, buf, 0, count);

    return buf;
  }
  /**
   * Encodes the authentication packet for supported authentication methods.
   *
   * @param request the socks proxy request data
   * @return the encoded buffer
   * @throws GSSException when something fails while using GSSAPI
   */
  private IoBuffer encodeGSSAPIAuthenticationPacket(final SocksProxyRequest request)
      throws GSSException {
    GSSContext ctx = (GSSContext) getSession().getAttribute(GSS_CONTEXT);
    if (ctx == null) {
      // first step in the authentication process
      GSSManager manager = GSSManager.getInstance();
      GSSName serverName = manager.createName(request.getServiceKerberosName(), null);
      Oid krb5OID = new Oid(SocksProxyConstants.KERBEROS_V5_OID);

      if (LOGGER.isDebugEnabled()) {
        LOGGER.debug("Available mechs:");
        for (Oid o : manager.getMechs()) {
          if (o.equals(krb5OID)) {
            LOGGER.debug("Found Kerberos V OID available");
          }
          LOGGER.debug("{} with oid = {}", manager.getNamesForMech(o), o);
        }
      }

      ctx = manager.createContext(serverName, krb5OID, null, GSSContext.DEFAULT_LIFETIME);

      ctx.requestMutualAuth(true); // Mutual authentication
      ctx.requestConf(false);
      ctx.requestInteg(false);

      getSession().setAttribute(GSS_CONTEXT, ctx);
    }

    byte[] token = (byte[]) getSession().getAttribute(GSS_TOKEN);
    if (token != null) {
      LOGGER.debug("  Received Token[{}] = {}", token.length, ByteUtilities.asHex(token));
    }
    IoBuffer buf = null;

    if (!ctx.isEstablished()) {
      // token is ignored on the first call
      if (token == null) {
        token = new byte[32];
      }

      token = ctx.initSecContext(token, 0, token.length);

      // Send a token to the server if one was generated by
      // initSecContext
      if (token != null) {
        LOGGER.debug("  Sending Token[{}] = {}", token.length, ByteUtilities.asHex(token));

        getSession().setAttribute(GSS_TOKEN, token);
        buf = IoBuffer.allocate(4 + token.length);
        buf.put(
            new byte[] {
              SocksProxyConstants.GSSAPI_AUTH_SUBNEGOTIATION_VERSION,
              SocksProxyConstants.GSSAPI_MSG_TYPE
            });

        buf.put(ByteUtilities.intToNetworkByteOrder(token.length, 2));
        buf.put(token);
      }
    }

    return buf;
  }