/// <summary>
        /// Create Trans2QueryFileInformation request for client to query information of file on server. 
        /// </summary>
        /// <param name = "messageId">the id of message, used to identity the request and the server response. </param>
        /// <param name = "sessionUid">the valid session id, must be response by server of the session setup request. </param>
        /// <param name = "treeId">the valid tree connect id, must be response by server of the tree connect. </param>
        /// <param name = "flags">
        /// The Flags field contains individual flags, as specified in [CIFS] sections 2.4.2 and 3.1.1. 
        /// </param>
        /// <param name = "flags2">
        /// The Flags2 field contains individual bit flags that, depending on the negotiated SMB dialect, indicate   
        /// various client and server capabilities. 
        /// </param>
        /// <param name = "fileId">the valid file id to operation on, response by server. </param>
        /// <param name = "transactOptions">
        /// A set of bit flags that alter the behavior of the requested operation. Unused bit fields MUST be set to  
        /// zero by the client sending the request, and MUST be ignored by the server receiving the request. The 
        /// client MAY set either or both of the following bit flags 
        /// </param>
        /// <param name = "timeOut">
        /// The maximum amount of time in milliseconds to wait for the operation to complete. The client SHOULD set  
        /// this to 0 to indicate that no time-out is given. If the operation does not complete within the specified  
        /// time, the server MAY abort the request and send a failure response. 
        /// </param>
        /// <param name = "isUsePathThrough">
        /// Indicates that the client is requesting a native Microsoft Windows NT operating system information level, 
        /// as specified in section 3.2.4.7 and in [MS-FSCC] section 2.4. 
        /// </param>
        /// <param name = "maxDataCount">
        /// This value MUST be the number of bytes that the client requests  to read from the file on server. 
        /// </param>
        /// <param name = "informationLevel">
        /// Indicates that client specifies the information it is requesting. Server return different data based on 
        /// the client's request. 
        /// </param>
        /// <param name = "extendedAttributeList">
        /// This field MUST contain an array of extended file attribute name value pairs. 
        /// </param>
        /// <returns>a query file information request packet </returns>
        private SmbTrans2QueryFileInformationRequestPacket CreateTrans2QueryFileInformationRequest(
            ushort messageId,
            ushort sessionUid,
            ushort treeId,
            SmbHeader_Flags_Values flags,
            SmbHeader_Flags2_Values flags2,
            ushort fileId,
            Trans2SmbParametersFlags transactOptions,
            uint timeOut,
            bool isUsePathThrough,
            ushort maxDataCount,
            QueryInformationLevel informationLevel,
            SMB_GEA[] extendedAttributeList)
        {
            // update information level
            if (isUsePathThrough)
            {
                informationLevel = (QueryInformationLevel)
                    (informationLevel + SmbCapability.CONST_SMB_INFO_PASSTHROUGH);
            }

            return new SmbTrans2QueryFileInformationRequestPacket(
                this.cifsClient.CreateTrans2QueryFileInformationRequest(
                messageId, sessionUid, treeId, (SmbFlags)flags, (SmbFlags2)flags2,
                this.capability.MaxParameterCount, maxDataCount, this.capability.MaxSetupCount,
                transactOptions, timeOut, "", fileId, informationLevel, extendedAttributeList));
        }
 /// <summary>
 /// to create a Trans2QueryPathInformation request packet.
 /// </summary>
 /// <param name="uid">This field SHOULD identify the authenticated instance of the user.</param>
 /// <param name="treeId">This field identifies the subdirectory (or tree) on the server that the client is
 /// accessing.</param>
 /// <param name="informationLevel">This field contains an information level code, which determines the
 /// information contained in the response.</param>
 /// <param name="name">A buffer containing the name of the file to be opened, created, or truncated. The
 /// string MUST be null terminated</param>
 /// <param name="extendedAttributeList">This field MUST contain an array of extended file attribute name value
 /// pairs. </param>
 /// <returns>a Trans2QueryPathInformation request packet</returns>
 /// <exception cref="System.NullReferenceException">There is no connection in context. </exception>
 public SmbTrans2QueryPathInformationRequestPacket CreateTrans2QueryPathInformationRequest(
     ushort uid,
     ushort treeId,
     QueryInformationLevel informationLevel,
     string name,
     SMB_GEA[] extendedAttributeList)
 {
     return this.CreateTrans2QueryPathInformationRequest(this.Context.GetMessageId(this.connectionId),
         uid, treeId, this.defaultParameters.Flag, this.defaultParameters.Flag2, this.defaultParameters.MaxParameterCount,
         this.defaultParameters.MaxDataCount, this.defaultParameters.MaxSetupCount, this.defaultParameters.Trans2SmbParametersFlags,
         this.defaultParameters.Timeout, informationLevel, name, extendedAttributeList);
 }
        /// <summary>
        /// to create a Trans2QueryPathInformation request packet.
        /// </summary>
        /// <param name="messageId">This field SHOULD be the multiplex ID that is used to associate a response with a
        /// request.</param>
        /// <param name="uid">This field SHOULD identify the authenticated instance of the user.</param>
        /// <param name="treeId">This field identifies the subdirectory (or tree) on the server that the client is
        /// accessing.</param>
        /// <param name="flags">An 8-bit field of 1-bit flags describing various features in effect for the
        /// message</param>
        /// <param name="flags2">A 16-bit field of 1-bit flags that represent various features in effect for the
        /// message. Unspecified bits are reserved and MUST be zero.</param>
        /// <param name="maxParameterCount">The maximum number of parameter bytes that the client will accept in the
        /// transaction reply. The server MUST NOT return more than this number of parameter bytes.</param>
        /// <param name="maxDataCount">The maximum number of data bytes that the client will accept in the transaction
        /// reply. The server MUST NOT return more than this number of data bytes.</param>
        /// <param name="maxSetupCount">Maximum number of setup bytes that the client will accept in the transaction
        /// reply. The server MUST NOT return more than this number of setup bytes</param>
        /// <param name="smbParametersFlags">A set of bit flags that alter the behavior of the requested operation.
        /// Unused bit fields MUST be set to zero by the client sending the request, and MUST be ignored by the server
        /// receiving the request. The client MAY set either or both of the following bit flags</param>
        /// <param name="timeout">The number of milliseconds the server SHOULD wait for completion of the transaction
        /// before generating a timeout. A value of zero indicates that the operation MUST NOT block.</param>
        /// <param name="informationLevel">This field contains an information level code, which determines the
        /// information contained in the response.</param>
        /// <param name="name">A buffer containing the name of the file to be opened, created, or truncated. The
        /// string MUST be null terminated</param>
        /// <param name="extendedAttributeList">This field MUST contain an array of extended file attribute name value
        /// pairs. </param>
        /// <returns>a Trans2QueryPathInformation request packet</returns>
        public SmbTrans2QueryPathInformationRequestPacket CreateTrans2QueryPathInformationRequest(
            ushort messageId,
            ushort uid,
            ushort treeId,
            SmbFlags flags,
            SmbFlags2 flags2,
            ushort maxParameterCount,
            ushort maxDataCount,
            byte maxSetupCount,
            Trans2SmbParametersFlags smbParametersFlags,
            uint timeout,
            QueryInformationLevel informationLevel,
            string name,
            SMB_GEA[] extendedAttributeList)
        {
            if (name == null)
            {
                name = string.Empty;
            }
            if (extendedAttributeList == null)
            {
                extendedAttributeList = new SMB_GEA[0];
            }

            SmbTrans2QueryPathInformationRequestPacket packet = new SmbTrans2QueryPathInformationRequestPacket();
            packet.SmbHeader = CifsMessageUtils.CreateSmbHeader(SmbCommand.SMB_COM_TRANSACTION2,
                messageId, uid, treeId, flags, flags2);

            // Set Smb_Parameters
            SMB_COM_TRANSACTION2_Request_SMB_Parameters smbParameters =
                new SMB_COM_TRANSACTION2_Request_SMB_Parameters();
            smbParameters.MaxParameterCount = maxParameterCount;
            smbParameters.MaxDataCount = maxDataCount;
            smbParameters.MaxSetupCount = maxSetupCount;
            smbParameters.Flags = (ushort)smbParametersFlags;
            smbParameters.Timeout = timeout;
            smbParameters.SetupCount = 1; // the correct count in word of the Setup is always 1.
            smbParameters.Setup = new ushort[] { (ushort)Trans2SubCommand.TRANS2_QUERY_PATH_INFORMATION };
            smbParameters.WordCount = (byte)(CifsMessageUtils.GetSize<SMB_COM_TRANSACTION2_Request_SMB_Parameters>(
                smbParameters) / NumBytesOfWord);

            // Set Smb_Data
            SMB_COM_TRANSACTION2_Request_SMB_Data smbData = new SMB_COM_TRANSACTION2_Request_SMB_Data();
            smbData.Name = CifsMessageUtils.ToSmbStringBytes(name,
                (flags2 & SmbFlags2.SMB_FLAGS2_UNICODE) == SmbFlags2.SMB_FLAGS2_UNICODE);

            // Set Trans2_Parameters
            TRANS2_QUERY_PATH_INFORMATION_Request_Trans2_Parameters trans2Parameters =
                new TRANS2_QUERY_PATH_INFORMATION_Request_Trans2_Parameters();
            trans2Parameters.InformationLevel = informationLevel;
            trans2Parameters.FileName = CifsMessageUtils.ToSmbStringBytes(name,
                (flags2 & SmbFlags2.SMB_FLAGS2_UNICODE) == SmbFlags2.SMB_FLAGS2_UNICODE);

            // The size of the preceding SmbParameters part plus Header part is an odd number for all cifs messages
            // Use Name field to judge whether needs to add one 16-bits align pad.
            if ((flags2 & SmbFlags2.SMB_FLAGS2_UNICODE) == SmbFlags2.SMB_FLAGS2_UNICODE && smbData.Name.Length
                % twoBytesAlign == 0)
            {
                // pad 1 byte for 16-bits align:
                smbData.Pad1 = new byte[1];
            }
            else
            {
                smbData.Pad1 = new byte[0];
            }

            // Set Trans2_Data
            TRANS2_QUERY_PATH_INFORMATION_Request_Trans2_Data trans2Data =
                new TRANS2_QUERY_PATH_INFORMATION_Request_Trans2_Data();
            trans2Data.GetExtendedAttributeList.GEAList = extendedAttributeList;
            trans2Data.GetExtendedAttributeList.SizeOfListInBytes =
                (uint)CifsMessageUtils.GetSize<uint>(trans2Data.GetExtendedAttributeList.SizeOfListInBytes);
            trans2Data.GetExtendedAttributeList.SizeOfListInBytes +=
                CifsMessageUtils.GetSmbQueryEAListSize(extendedAttributeList);

            packet.SmbParameters = smbParameters;
            packet.SmbData = smbData;
            packet.Trans2Parameters = trans2Parameters;
            packet.Trans2Data = trans2Data;
            packet.UpdateCountAndOffset();

            return packet;
        }
        /// <summary>
        /// to create a Trans2QueryFileInformation request packet.
        /// </summary>
        /// <param name="messageId">This field SHOULD be the multiplex ID that is used to associate a response with a
        /// request.</param>
        /// <param name="uid">This field SHOULD identify the authenticated instance of the user.</param>
        /// <param name="treeId">This field identifies the subdirectory (or tree) on the server that the client is
        /// accessing.</param>
        /// <param name="flags">An 8-bit field of 1-bit flags describing various features in effect for the
        /// message</param>
        /// <param name="flags2">A 16-bit field of 1-bit flags that represent various features in effect for the
        /// message. Unspecified bits are reserved and MUST be zero.</param>
        /// <param name="maxParameterCount">The maximum number of parameter bytes that the client will accept in the
        /// transaction reply. The server MUST NOT return more than this number of parameter bytes.</param>
        /// <param name="maxDataCount">The maximum number of data bytes that the client will accept in the transaction
        /// reply. The server MUST NOT return more than this number of data bytes.</param>
        /// <param name="maxSetupCount">Maximum number of setup bytes that the client will accept in the transaction
        /// reply. The server MUST NOT return more than this number of setup bytes</param>
        /// <param name="smbParametersFlags">A set of bit flags that alter the behavior of the requested operation.
        /// Unused bit fields MUST be set to zero by the client sending the request, and MUST be ignored by the server
        /// receiving the request. The client MAY set either or both of the following bit flags</param>
        /// <param name="timeout">The number of milliseconds the server SHOULD wait for completion of the transaction
        /// before generating a timeout. A value of zero indicates that the operation MUST NOT block.</param>
        /// <param name="informationLevel">This field contains an information level code, which determines the
        /// information contained in the response.</param>
        /// <param name="fid">This field MUST contain a valid FID returned from a previously successful SMB open
        /// command</param>
        /// <param name="name">This field is present but not used in SMB_COM_TRANSACTION2 requests. If Unicode support
        /// has been negotiated, then this field MUST be aligned to a 16-bit boundary and MUST consist of two null bytes
        /// (a null-terminator). If Unicode support has not been negotiated this field will contain only one null
        /// byte.</param>
        /// <param name="extendedAttributeList">This field MUST contain an array of extended file attribute name value
        /// pairs.</param>
        /// <returns>a Trans2QueryFileInformation request packet</returns>
        public SmbTrans2QueryFileInformationRequestPacket CreateTrans2QueryFileInformationRequest(
            ushort messageId,
            ushort uid,
            ushort treeId,
            SmbFlags flags,
            SmbFlags2 flags2,
            ushort maxParameterCount,
            ushort maxDataCount,
            byte maxSetupCount,
            Trans2SmbParametersFlags smbParametersFlags,
            uint timeout,
            string name,
            ushort fid,
            QueryInformationLevel informationLevel,
            SMB_GEA[] extendedAttributeList)
        {
            if (name == null)
            {
                name = string.Empty;
            }
            if (extendedAttributeList == null)
            {
                extendedAttributeList = new SMB_GEA[0];
            }

            SmbTrans2QueryFileInformationRequestPacket packet = new SmbTrans2QueryFileInformationRequestPacket();
            packet.SmbHeader = CifsMessageUtils.CreateSmbHeader(SmbCommand.SMB_COM_TRANSACTION2,
                messageId, uid, treeId, flags, flags2);

            // Set Smb_Parameters
            SMB_COM_TRANSACTION2_Request_SMB_Parameters smbParameters =
                new SMB_COM_TRANSACTION2_Request_SMB_Parameters();
            smbParameters.MaxParameterCount = maxParameterCount;
            smbParameters.MaxDataCount = maxDataCount;
            smbParameters.MaxSetupCount = maxSetupCount;
            smbParameters.Flags = (ushort)smbParametersFlags;
            smbParameters.Timeout = timeout;
            smbParameters.SetupCount = 1; // the correct count in word of the Setup is always 1.
            smbParameters.Setup = new ushort[] { (ushort)Trans2SubCommand.TRANS2_QUERY_FILE_INFORMATION };
            smbParameters.WordCount = (byte)(CifsMessageUtils.GetSize<SMB_COM_TRANSACTION2_Request_SMB_Parameters>(
                smbParameters) / NumBytesOfWord);

            // Set Smb_Data
            SMB_COM_TRANSACTION2_Request_SMB_Data smbData = new SMB_COM_TRANSACTION2_Request_SMB_Data();
            smbData.Name = CifsMessageUtils.ToSmbStringBytes(name,
                (flags2 & SmbFlags2.SMB_FLAGS2_UNICODE) == SmbFlags2.SMB_FLAGS2_UNICODE);

            // Set Trans2_Parameters
            TRANS2_QUERY_FILE_INFORMATION_Request_Trans2_Parameters trans2Parameters =
                new TRANS2_QUERY_FILE_INFORMATION_Request_Trans2_Parameters();
            trans2Parameters.FID = fid;
            trans2Parameters.InformationLevel = informationLevel;

            // Set Trans2_Data
            TRANS2_QUERY_PATH_INFORMATION_Request_Trans2_Data trans2Data =
                new TRANS2_QUERY_PATH_INFORMATION_Request_Trans2_Data();
            trans2Data.GetExtendedAttributeList.GEAList = extendedAttributeList;
            trans2Data.GetExtendedAttributeList.SizeOfListInBytes =
                (uint)CifsMessageUtils.GetSize<uint>(trans2Data.GetExtendedAttributeList.SizeOfListInBytes);
            trans2Data.GetExtendedAttributeList.SizeOfListInBytes +=
                CifsMessageUtils.GetSmbQueryEAListSize(extendedAttributeList);

            packet.SmbParameters = smbParameters;
            packet.SmbData = smbData;
            packet.Trans2Parameters = trans2Parameters;
            packet.Trans2Data = trans2Data;
            packet.UpdateCountAndOffset();

            return packet;
        }
 /// <summary>
 /// to create a Trans2FindNext2 request packet.
 /// </summary>
 /// <param name="uid">This field SHOULD identify the authenticated instance of the user.</param>
 /// <param name="treeId">This field identifies the subdirectory (or tree) on the server that the client is
 /// accessing.</param>
 /// <param name="sid">This field MUST be the search identifier (SID) returned in TRANS2_FIND_FIRST2
 /// response.</param>
 /// <param name="searchCount">The server MUST NOT return more entries than indicated by the value of this
 /// field.</param>
 /// <param name="informationLevel">This field contains an information level code, which determines the
 /// information contained in the response.</param>
 /// <param name="resumeKey">This field MUST be the value of a ResumeKey field returned in the response from a
 /// TRANS2_FIND_FIRST2 or TRANS2_FIND_NEXT2 that is part of the same search (same SID).</param>
 /// <param name="findFlags">This 16-bit field of flags is used to request that the server take
 /// certain actions.</param>
 /// <param name="name">A buffer containing the name of the file to be opened, created, or truncated. The
 /// string MUST be null terminated</param>
 /// <param name="extendedAttributeList">Array of SMB_EA A list of extended file attribute name/value pairs.
 /// </param>
 /// <returns>a Trans2FindNext2 request packet</returns>
 /// <exception cref="System.NullReferenceException">There is no connection in context. </exception>
 public SmbTrans2FindNext2RequestPacket CreateTrans2FindNext2Request(
     ushort uid,
     ushort treeId,
     ushort sid,
     ushort searchCount,
     FindInformationLevel informationLevel,
     uint resumeKey,
     Trans2FindFlags findFlags,
     string name,
     SMB_GEA[] extendedAttributeList)
 {
     return this.CreateTrans2FindNext2Request(this.Context.GetMessageId(this.connectionId),
         uid, treeId, this.defaultParameters.Flag, this.defaultParameters.Flag2, this.defaultParameters.MaxParameterCount,
         this.defaultParameters.MaxDataCount, this.defaultParameters.MaxSetupCount, this.defaultParameters.Trans2SmbParametersFlags,
         this.defaultParameters.Timeout, sid, searchCount, informationLevel, resumeKey, findFlags, name,
         extendedAttributeList);
 }
 /// <summary>
 /// to create a Trans2FindFirst2 request packet.
 /// </summary>
 /// <param name="uid">This field SHOULD identify the authenticated instance of the user.</param>
 /// <param name="treeId">This field identifies the subdirectory (or tree) on the server that the client is
 /// accessing.</param>
 /// <param name="extendedAttributeList">A list of extended file attribute name/value pairs. </param>
 /// <param name="searchCount">The server MUST NOT return more entries than indicated by the value of this
 /// field.</param>
 /// <param name="searchAttributes">File attributes to apply as a constraint to the file search.</param>
 /// <param name="findFlags">This 16-bit field of flags is used to request that the server take
 /// certain actions.</param>
 /// <param name="informationLevel">This field contains an information level code, which determines the
 /// information contained in the response.</param>
 /// <param name="searchStorageType">This field specifies if the find is searching for directories or for files.
 /// This field MUST be one of two values</param>
 /// <param name="name">A buffer containing the name of the file to be opened, created, or truncated. The
 /// string MUST be null terminated</param>
 /// <returns>a Trans2FindFirst2 request packet</returns>
 /// <exception cref="System.NullReferenceException">There is no connection in context. </exception>
 public SmbTrans2FindFirst2RequestPacket CreateTrans2FindFirst2Request(
     ushort uid,
     ushort treeId,
     SmbFileAttributes searchAttributes,
     Trans2FindFlags findFlags,
     ushort searchCount,
     FindInformationLevel informationLevel,
     Trans2FindFirst2SearchStorageType searchStorageType,
     string name,
     SMB_GEA[] extendedAttributeList)
 {
     return this.CreateTrans2FindFirst2Request(this.Context.GetMessageId(this.connectionId),
         uid, treeId, this.defaultParameters.Flag, this.defaultParameters.Flag2, this.defaultParameters.MaxParameterCount,
         this.defaultParameters.MaxDataCount, this.defaultParameters.MaxSetupCount, this.defaultParameters.Trans2SmbParametersFlags,
         this.defaultParameters.Timeout, searchAttributes, searchCount, findFlags, informationLevel,
         searchStorageType, name, extendedAttributeList);
 }