A type of PDU to indicate some errors.
Наследование: RdpbcgrClientPdu
        /// <summary>
        /// Decode RDPBCGR PDUs from the received message bytes
        /// </summary>
        /// <param name="endPoint">the endpoint from which the message bytes are received.</param>
        /// <param name="receivedBytes">the received message bytes to be decoded.</param>
        /// <param name="consumedLength">the length of message bytes consumed by decoder.</param>
        /// <param name="expectedLength">the length of message bytes the decoder expects to receive.</param>
        /// <returns>the stack packets decoded from the received message bytes.</returns>
        internal StackPacket[] DecodePacketCallback(
            object endPoint,
            byte[] receivedBytes,
            out int consumedLength,
            out int expectedLength)
        {
            StackPacket pdu = null;
            expectedLength = 0;

            // Get bytes for only one packet
            byte[] packetData = GetPacket(receivedBytes);
            if (null == packetData)
            {
                // Received bytes does not contain enough data
                consumedLength = 0;
                return null;
            }
            consumedLength = packetData.Length;

            // Decode PDU
            try
            {
                pdu = DecodePdu(packetData);
                if (pdu.GetType() == typeof(Server_X_224_Connection_Confirm_Pdu))
                {
                    // Negotiation-based security-enhanced Connection
                    client.UpdateTransport();
                }
            }
            catch (FormatException e)
            {
                pdu = new ErrorPdu(e);
            }

            // Update client context and client
            clientContext.UpdateContext(pdu);
            client.CheckDecryptionCount();
            return new StackPacket[] { pdu };
        }
        /// <summary>
        /// Decode RDPBCGR PDUs from the received message bytes
        /// </summary>
        /// <param name="endPoint">the endpoint from which the message bytes are received.</param>
        /// <param name="receivedBytes">the received message bytes to be decoded.</param>
        /// <param name="consumedLength">the length of message bytes consumed by decoder.</param>
        /// <param name="expectedLength">the length of message bytes the decoder expects to receive.</param>
        /// <returns>the stack packets decoded from the received message bytes.</returns>
        internal StackPacket[] DecodePacketCallback(
            object endPoint,
            byte[] receivedBytes,
            out int consumedLength,
            out int expectedLength)
        {
            StackPacket pdu = null;
            expectedLength = 0;

            // Get bytes for only one packet
            byte[] packetData = GetPacket(receivedBytes);
            if (null == packetData)
            {
                // Received bytes does not contain enough data
                consumedLength = 0;
                return null;
            }
            consumedLength = packetData.Length;

            for (int i = 0; i < server.ServerContext.SessionContexts.Count; i++)
            {
                if (endPoint == server.ServerContext.SessionContexts[i].Identity)
                {
                    try
                    {
                        // ETW Provider Dump Message
                        string messageName;
                        if (ConstValue.SLOW_PATH_PDU_INDICATOR_VALUE == packetData[ConstValue.SLOW_PATH_PDU_INDICATOR_INDEX])
                        {
                            // Slow-Path
                            messageName = "RDPBCGR:ReceivedSlowPathPDU";
                        }
                        else
                        {
                            // Fast-Path
                            messageName = "RDPBCGR:ReceivedFastPathPDU";
                        }
                        ExtendedLogger.DumpMessage(messageName, RdpbcgrUtility.DumpLevel_Layer0, "Received Original RDPBCGR Message", packetData);

                        pdu = DecodePdu(server.ServerContext.SessionContexts[i], packetData);
                    }
                    catch (FormatException e)
                    {
                        pdu = new ErrorPdu(e, packetData);
                    }

                    // Update client context and client
                    server.ServerContext.SessionContexts[i].UpdateContext(pdu);
                    server.CheckDecryptionCount(server.ServerContext.SessionContexts[i]);

                    break;
                }
                else
                {
                    pdu = null;
                }
            }
            return new StackPacket[] { pdu };
        }