public HandshakeServerHello(ProtocolVersion version)
     : base(HandshakeMessageType.ServerHello, version)
 {
     ServerVersion = version;
     Random = new HandshakeRandom();
     SessionID = new byte[0];
     CipherSuite = 0x0000;
     CompressionMethod = 0x00;
     Extensions = new List<HelloExtension>();
 }
        protected override void DecodeDataBytes(ProtocolVersion ver, byte[] data)
        {
            MemoryStream memStream = new MemoryStream(data);
            HandshakeStream stream = new HandshakeStream(memStream);

            byte major = stream.ReadUInt8();
            byte minor = stream.ReadUInt8();
            ServerVersion = new ProtocolVersion(major, minor);

            byte[] randomBytes = stream.ReadBytes(32);
            Random = new HandshakeRandom(randomBytes);

            int idLength = (int)stream.ReadUInt8();
            SessionID = stream.ReadBytes(idLength);
            Trace.WriteLine($"SessionId: {SessionID}");

            CipherSuite = (CipherSuiteId)stream.ReadUInt16();
            Trace.WriteLine($"Cipher Suite Id: {CipherSuite} refer to list at http://www.thesprawl.org/research/tls-and-ssl-cipher-suites/");
            CompressionMethod = stream.ReadUInt8();

            byte[] extensionList = new byte[0];
            if (!stream.EndOfStream && ServerVersion.HasExtensions)
            {
                UInt16 extensionListLength = stream.ReadUInt16();
                extensionList = stream.ReadBytes(extensionListLength);
            }
            stream.ConfirmEndOfStream();

            int pos = 0;
            while (pos + 4 <= extensionList.Length)
            {
                HelloExtensionType extensionType = (HelloExtensionType)(UInt16)((extensionList[pos] << 8) | extensionList[pos + 1]);
                Trace.WriteLine($"Extension Type { extensionType }");
                UInt16 extensionDataLength = (UInt16)((extensionList[pos + 2] << 8) | extensionList[pos + 3]);
                pos += 4;

                if (pos + extensionDataLength > extensionList.Length)
                {
                    throw new AlertException(AlertDescription.IllegalParameter,
                                             "ServerHello extension data length too large: " + extensionDataLength);
                }

                byte[] extensionData = new byte[extensionDataLength];
                Buffer.BlockCopy(extensionList, pos, extensionData, 0, extensionData.Length);
                pos += extensionData.Length;

                Extensions.Add(new HelloExtension(extensionType, extensionData));
            }
        }