Fast-path revises server output packets from the first byte with the goal of improving bandwidth. The TPKT (see [T123]), X.224 (see [X224]) and MCS SDin (see [T125]) headers are replaced, the Security Header is collapsed into the fast-path output header, and the Share Data Header is replaced by a new fast-path format. The contents of the graphics and pointer updates (see sections and ) are also changed to reduce their size, particularly by removing or reducing headers. Support for fast-path output is advertised in the General Capability Set.
file:///C:/ts_dev/TestSuites/MS-RDPBCGR/TestSuite/Src/TD/latest_XMLS_16may/RDPBCGR/ _rfc_ms-rdpbcgr2_1_8_1_2.xml
Inheritance: RdpbcgrServerPdu
TS_FP_UPDATE_PDU Class Documentation
Example #1
0
        /// <summary>
        /// Decode Fast-path Update PDU
        /// </summary>
        /// <param name="data">data to be parsed</param>
        /// <returns>decoded Fast-path Update PDU</returns>
        public StackPacket DecodeTsFpUpdatePDU(byte[] data)
        {
            // initialize
            int currentIndex = 0;
            TS_FP_UPDATE_PDU pdu = new TS_FP_UPDATE_PDU();

            // TS_FP_UPDATE_PDU: fpOutputHeader
            pdu.fpOutputHeader = ParseByte(data, ref currentIndex);

            // Get infomation from fpOutputHeader
            nested_TS_FP_UPDATE_PDU_fpOutputHeader_actionCode_Values actionCode;
            encryptionFlagsChgd_Values encryptionFlags;
            GetFpOutputHeaderInfo(pdu.fpOutputHeader, out actionCode, out encryptionFlags);

            // TS_FP_UPDATE_PDU: length1
            pdu.length1 = ParseByte(data, ref currentIndex);

            // TS_FP_UPDATE_PDU: length2 (optional)
            if ((ConstValue.MOST_SIGNIFICANT_BIT_FILTER & pdu.length1) != pdu.length1)
            {
                // length2 is present (since the most significant bit of length1 is set)
                pdu.length2 = ParseByte(data, ref currentIndex);
            }

            // TS_FP_UPDATE_PDU: fipsInformation
            if (EncryptionLevel.ENCRYPTION_LEVEL_FIPS == clientContext.RdpEncryptionLevel)
            {
                pdu.fipsInformation = ParseTsFpFipsInfo(data, ref currentIndex);
            }

            // TS_FP_UPDATE_PDU: dataSignature
            if (IsFlagExist((byte)encryptionFlags, (byte)encryptionFlagsChgd_Values.FASTPATH_OUTPUT_ENCRYPTED))
            {
                // pdu were encrypted, data signature exists
                pdu.dataSignature = GetBytes(data, ref currentIndex,
                    ConstValue.TS_FP_UPDATE_PDU_DATA_SIGNATURE_LENGTH);
            }
            else
            {
                pdu.dataSignature = null;
            }

            // Decryption
            bool isSalted = IsFlagExist((byte)encryptionFlags,
                (byte)encryptionFlagsChgd_Values.FASTPATH_OUTPUT_SECURE_CHECKSUM);
            byte[] remainData = GetBytes(data, ref currentIndex, (data.Length - currentIndex));
            byte[] decryptedData = DecryptFastPathUpdateData(remainData, pdu.dataSignature, isSalted);

            // Decrypted data index
            int decryptedDataIndex = 0;

            // TS_FP_UPDATE_PDU: fpOutputUpdates
            pdu.fpOutputUpdates = ParseTsFpUpdates(decryptedData, ref decryptedDataIndex);

            // Check if data length exceeded expectation
            VerifyDataLength(decryptedData.Length, decryptedDataIndex, ConstValue.ERROR_MESSAGE_DATA_LENGTH_EXCEEDED);
            return pdu;
        }
Example #2
0
        public static TS_FP_UPDATE_PDU CreateFPUpdatePDU(RdpbcgrServerSessionContext context, TS_FP_UPDATE update)
        {
            TS_FP_UPDATE_PDU fpOutput = new TS_FP_UPDATE_PDU(context);

            fpOutput.fpOutputHeader = (byte)(((int)nested_TS_FP_UPDATE_PDU_fpOutputHeader_actionCode_Values.FASTPATH_OUTPUT_ACTION_FASTPATH & 0x03)
                | ((int)((int)reserved_Values.V1 & 0x0f) << 2));
            fpOutput.dataSignature = null;
            fpOutput.length1 = 0;
            fpOutput.length2 = 0;

            fpOutput.fpOutputUpdates = new TS_FP_UPDATE[1];
            fpOutput.fpOutputUpdates[0] = update;

            return fpOutput;
        }