private bool TryCreateNewAssembler(out FileTransfer.FileStreamAssembler assembler, FileTransfer.FileStreamAssemblerList fileStreamAssemblerList, Packets.TftpPacket tftpPacket, NetworkHost sourceHost, ushort sourcePort, NetworkHost destinationHost) //destinationPort is not needed
{
assembler = null;
//create new assembler if it is a RRQ or WRQ
if (tftpPacket.OpCode == Packets.TftpPacket.OpCodes.ReadRequest)
{
try {
FiveTuple tmpFiveTuple = new FiveTuple(destinationHost, Packets.TftpPacket.DefaultUdpPortNumber, sourceHost, sourcePort, FiveTuple.TransportProtocol.UDP);
assembler = new FileTransfer.FileStreamAssembler(fileStreamAssemblerList, tmpFiveTuple, true, FileTransfer.FileStreamTypes.TFTP, tftpPacket.Filename, "", tftpPacket.OpCode.ToString() + " " + tftpPacket.Mode.ToString() + " " + tftpPacket.Filename, tftpPacket.ParentFrame.FrameNumber, tftpPacket.ParentFrame.Timestamp);
fileStreamAssemblerList.Add(assembler);
}
catch (Exception e) {
SharedUtils.Logger.Log("Error creating assembler for TFTP file transfer in " + tftpPacket.ParentFrame.ToString() + ". " + e.ToString(), SharedUtils.Logger.EventLogEntryType.Information);
//throw new Exception("Error creating assembler for TFTP file transfer", e);
//this.parentForm.ShowError("Error creating assembler for TFTP file transfer: "+e.Message);
if (assembler != null)
{
assembler.Clear();
assembler = null;
}
return(false);
}
return(true);
}
else if (tftpPacket.OpCode == Packets.TftpPacket.OpCodes.WriteRequest)
{
try {
FiveTuple tmpFiveTuple = new FiveTuple(sourceHost, sourcePort, destinationHost, Packets.TftpPacket.DefaultUdpPortNumber, FiveTuple.TransportProtocol.UDP);
assembler = new FileTransfer.FileStreamAssembler(fileStreamAssemblerList, tmpFiveTuple, true, FileTransfer.FileStreamTypes.TFTP, tftpPacket.Filename, "", tftpPacket.OpCode.ToString() + " " + tftpPacket.Mode.ToString() + " " + tftpPacket.Filename, tftpPacket.ParentFrame.FrameNumber, tftpPacket.ParentFrame.Timestamp);
fileStreamAssemblerList.Add(assembler);
}
catch (Exception e) {
SharedUtils.Logger.Log("Error creating assembler for TFTP file transfer in " + tftpPacket.ParentFrame.ToString() + ". " + e.ToString(), SharedUtils.Logger.EventLogEntryType.Information);
//throw new Exception("Error creating assembler for TFTP file transfer", e);
//this.parentForm.ShowError("Error creating assembler for TFTP file transfer: "+e.Message);
if (assembler != null)
{
assembler.Clear();
assembler = null;
}
return(false);
}
return(true);
}
else
{
assembler = null;
return(false);
}
}
private void ExtractFileData(FileTransfer.FileStreamAssembler assembler, FileTransfer.FileStreamAssemblerList fileStreamAssemblerList, NetworkHost sourceHost, ushort sourcePort, NetworkHost destinationHost, ushort destinationPort, Packets.TftpPacket tftpPacket)
{
if (tftpPacket.OpCode == Packets.TftpPacket.OpCodes.Data)
{
if (!assembler.IsActive)
{
//create a new active assembler if ports need to be changed!
if (assembler.SourcePort != sourcePort || assembler.DestinationPort != destinationPort)
{
fileStreamAssemblerList.Remove(assembler, true);
//now change the port number in the AssemblerPool
FiveTuple tmpFiveTuple = new FiveTuple(sourceHost, sourcePort, destinationHost, destinationPort, FiveTuple.TransportProtocol.UDP);
assembler = new FileTransfer.FileStreamAssembler(fileStreamAssemblerList, tmpFiveTuple, true, FileTransfer.FileStreamTypes.TFTP, assembler.Filename, assembler.FileLocation, assembler.Details, tftpPacket.ParentFrame.FrameNumber, tftpPacket.ParentFrame.Timestamp);
fileStreamAssemblerList.Add(assembler);
}
//activate the assembler
assembler.TryActivate();
}
if (assembler.SourceHost == sourceHost && assembler.SourcePort == sourcePort && assembler.DestinationHost == destinationHost && assembler.DestinationPort == destinationPort)
{
assembler.AddData(tftpPacket.DataBlock, tftpPacket.DataBlockNumber);
if (tftpPacket.DataBlockIsLast)
{
assembler.FinishAssembling();//we now have the complete file
}
}
}
}
