public int ExtractData(NetworkTcpSession tcpSession, NetworkHost sourceHost, NetworkHost destinationHost, IEnumerable <Packets.AbstractPacket> packetList)
{
Packets.TcpPacket tcpPacket = null;
Packets.FtpPacket ftpPacket = null;
foreach (Packets.AbstractPacket p in packetList)
{
if (p.GetType() == typeof(Packets.TcpPacket))
{
tcpPacket = (Packets.TcpPacket)p;
}
else if (p.GetType() == typeof(Packets.FtpPacket))
{
ftpPacket = (Packets.FtpPacket)p;
}
}
FtpSession ftpSession = null;//we can only have one FtpSession per packet...
bool returnValue = false;
if (tcpSession.SynPacketReceived && tcpSession.SynAckPacketReceived)
{
//start by checking if this is an incoming file transfer through FTP
if (!tcpSession.SessionEstablished)
{
//we now have an upcoming session
//see if it matches the pending FTP data sessions
if (this.pendingFileTransferList.ContainsKey(PendingFileTransfer.GetKey(tcpSession.ClientHost, tcpSession.ClientTcpPort, tcpSession.ServerHost, tcpSession.ServerTcpPort)))
{
PendingFileTransfer pending = this.pendingFileTransferList[PendingFileTransfer.GetKey(tcpSession.ClientHost, tcpSession.ClientTcpPort, tcpSession.ServerHost, tcpSession.ServerTcpPort)];
pending.FileTransferSessionEstablished = true;
ftpSession = pending.FtpControlSession;
returnValue = true;//we managed to get some data out of this!
}
//see if the client port was unknown
else if (this.pendingFileTransferList.ContainsKey(PendingFileTransfer.GetKey(tcpSession.ClientHost, null, tcpSession.ServerHost, tcpSession.ServerTcpPort)))
{
PendingFileTransfer pending = this.pendingFileTransferList[PendingFileTransfer.GetKey(tcpSession.ClientHost, null, tcpSession.ServerHost, tcpSession.ServerTcpPort)];
this.pendingFileTransferList.Remove(pending.GetKey());
pending.DataSessionClientPort = tcpSession.ClientTcpPort;//the Key will now be changed!
pending.FileTransferSessionEstablished = true;
this.pendingFileTransferList.Add(pending.GetKey(), pending);
ftpSession = pending.FtpControlSession;
returnValue = true;
}
}//end check for new FTP DATA sessions
else if (tcpPacket != null && tcpPacket.FlagBits.Fin)
{
//check if there is an FTP data session being closed
if (this.MainPacketHandler.FileStreamAssemblerList.ContainsAssembler(sourceHost, tcpPacket.SourcePort, destinationHost, tcpPacket.DestinationPort, true, true, PacketParser.FileTransfer.FileStreamTypes.FTP))
{
PacketParser.FileTransfer.FileStreamAssembler assembler = this.MainPacketHandler.FileStreamAssemblerList.GetAssembler(sourceHost, tcpPacket.SourcePort, destinationHost, tcpPacket.DestinationPort, true);
if (assembler.FileContentLength == -1 && assembler.FileSegmentRemainingBytes == -1)
{
//TODO: see if all data has been received or if the FIN arrived before the final data packet
assembler.FinishAssembling();
}
}
}
}
if (ftpPacket != null && tcpPacket != null)
{
returnValue = true;
if (ftpSessionList.ContainsKey(tcpSession))
{
ftpSession = ftpSessionList[tcpSession];
}
else
{
ftpSession = new FtpSession(tcpSession.ClientHost, tcpSession.ServerHost);
this.ftpSessionList.Add(tcpSession, ftpSession);
}
if (ftpPacket.ClientToServer)
{
if (ftpPacket.RequestCommand != null)
{
if (ftpPacket.RequestArgument != null)
{
System.Collections.Specialized.NameValueCollection tmpCol = new System.Collections.Specialized.NameValueCollection();
tmpCol.Add(ftpPacket.RequestCommand, ftpPacket.RequestArgument);
base.MainPacketHandler.OnParametersDetected(new Events.ParametersEventArgs(ftpPacket.ParentFrame.FrameNumber, sourceHost, destinationHost, "TCP " + tcpPacket.SourcePort, "TCP " + tcpPacket.DestinationPort, tmpCol, ftpPacket.ParentFrame.Timestamp, "FTP Request"));
}
if (ftpPacket.RequestCommand.ToUpper() == "USER")//username
{
ftpSession.Username = ftpPacket.RequestArgument;
}
else if (ftpPacket.RequestCommand.ToUpper() == "PASS")//password
{
ftpSession.Password = ftpPacket.RequestArgument;
if (ftpSession.Username != null && ftpSession.Password != null)
{
base.MainPacketHandler.AddCredential(new NetworkCredential(tcpSession.ClientHost, tcpSession.ServerHost, ftpPacket.PacketTypeDescription, ftpSession.Username, ftpSession.Password, ftpPacket.ParentFrame.Timestamp));
}
}
else if (ftpPacket.RequestCommand.ToUpper() == "PORT")
{
ushort clientListeningOnPort;
if (TryGetPort(ftpPacket.RequestArgument, out clientListeningOnPort))
{
//ftpSession.ActiveMode=true;
//ftpSession.ClientDataListenerTcpPort=this.GetPort(ftpPacket.RequestArgument);
//ftpSession.PendingFileTransfer=new PendingFileTransfer(ftpSession.ServerHost, (ushort)20, ftpSession.ClientHost, clientListeningOnPort, false, ftpSession);
ftpSession.PendingFileTransfer = new PendingFileTransfer(ftpSession.ServerHost, null, ftpSession.ClientHost, clientListeningOnPort, false, ftpSession);
if (this.pendingFileTransferList.ContainsKey(ftpSession.PendingFileTransfer.GetKey()))
{
this.pendingFileTransferList.Remove(ftpSession.PendingFileTransfer.GetKey());
}
this.pendingFileTransferList.Add(ftpSession.PendingFileTransfer.GetKey(), ftpSession.PendingFileTransfer);
}
}
else if (ftpPacket.RequestCommand.ToUpper() == "STOR")//file upload (client -> server)
//set filename and file direction
{
if (ftpSession.PendingFileTransfer != null)
{
ftpSession.PendingFileTransfer.Filename = ftpPacket.RequestArgument;
ftpSession.PendingFileTransfer.FileDirectionIsDataSessionServerToDataSessionClient = !ftpSession.PendingFileTransfer.DataSessionIsPassive;
ftpSession.PendingFileTransfer.Details = ftpPacket.RequestCommand + " " + ftpPacket.RequestArgument;
}
else
{
//ftpPacket.ParentFrame.Errors.Add(new Frame.Error(ftpPacket.ParentFrame, ftpPacket.PacketStartIndex, ftpPacket.PacketEndIndex, "STOR command without a pending ftp data session"));
this.MainPacketHandler.OnAnomalyDetected("STOR command without a pending ftp data session. Frame: " + ftpPacket.ParentFrame.ToString(), ftpPacket.ParentFrame.Timestamp);
//System.Diagnostics.Debugger.Break();//this should not occur!
}
}
else if (ftpPacket.RequestCommand.ToUpper() == "RETR")//file download (server -> client)
{
if (ftpSession.PendingFileTransfer != null)
{
ftpSession.PendingFileTransfer.Filename = ftpPacket.RequestArgument;
ftpSession.PendingFileTransfer.FileDirectionIsDataSessionServerToDataSessionClient = ftpSession.PendingFileTransfer.DataSessionIsPassive;
ftpSession.PendingFileTransfer.Details = ftpPacket.RequestCommand + " " + ftpPacket.RequestArgument;
}
else
{
//System.Diagnostics.Debugger.Break();//this should not iccur
//ftpPacket.ParentFrame.Errors.Add(new Frame.Error(ftpPacket.ParentFrame, ftpPacket.PacketStartIndex, ftpPacket.PacketEndIndex, "RETR command without a pending ftp data session"));
this.MainPacketHandler.OnAnomalyDetected("RETR command without a pending ftp data session. Frame: " + ftpPacket.ParentFrame.ToString(), ftpPacket.ParentFrame.Timestamp);
}
}
else if (ftpPacket.RequestCommand.ToUpper() == "SIZE")
{
ftpSession.PendingSizeRequestFileName = ftpPacket.RequestArgument;
}
}
}
else //server to client packet
{
if (ftpPacket.ResponseCode != 0 && ftpPacket.ResponseArgument != null)
{
System.Collections.Specialized.NameValueCollection tmpCol = new System.Collections.Specialized.NameValueCollection();
tmpCol.Add(ftpPacket.ResponseCode.ToString(), ftpPacket.ResponseArgument);
MainPacketHandler.OnParametersDetected(new Events.ParametersEventArgs(ftpPacket.ParentFrame.FrameNumber, sourceHost, destinationHost, "TCP " + tcpPacket.SourcePort, "TCP " + tcpPacket.DestinationPort, tmpCol, ftpPacket.ParentFrame.Timestamp, "FTP Response"));
//look for an FTP banner
if (ftpPacket.ResponseCode == 220 && ftpPacket.ResponseArgument.ToLower().Contains("ftp"))
{
sourceHost.AddFtpServerBanner(ftpPacket.ResponseArgument, tcpPacket.SourcePort);
}
}
if (ftpPacket.ResponseCode == 213 && ftpSession.PendingSizeRequestFileName != null)//File size response
{
int fileSize;
if (Int32.TryParse(ftpPacket.ResponseArgument, out fileSize))
{
ftpSession.FileSizes[ftpSession.PendingSizeRequestFileName] = fileSize;
}
//ftpSession.FileSizes.Add(ftpSession.PendingSizeRequestFileName, fileSize);
ftpSession.PendingSizeRequestFileName = null;
}
if (ftpPacket.ResponseCode == 226)//File receive OK
//close file stream assembler?
{
}
else if (ftpPacket.ResponseCode == 227)//Entering Passive Mode
//From: http://cr.yp.to/ftp/retr.html
//Many servers put different strings before h1 and after p2.
//I recommend that clients use the following strategy to parse the
//response line: look for the first digit after the initial space;
//look for the fourth comma after that digit; read two (possibly negative)
//integers, separated by a comma; the TCP port number is p1*256+p2,
//where p1 is the first integer modulo 256 and p2 is the second integer
//modulo 256.
//it is probably simpler to do this with RegEx, but this is simple enough so I wont bother with RegEx for now...
{
char[] digits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };
string ipAndPort = ftpPacket.ResponseArgument.Substring(ftpPacket.ResponseArgument.IndexOfAny(digits));
//string ipAndPort=ftpPacket.ResponseArgument.Substring(ftpPacket.ResponseArgument.IndexOf('(')+1);
ipAndPort = ipAndPort.Substring(0, ipAndPort.LastIndexOfAny(digits) + 1);
//ipAndPort=ipAndPort.Substring(0, ipAndPort.IndexOf(')'));
ushort serverListeningOnPort;
if (this.TryGetPort(ipAndPort, out serverListeningOnPort))
{
ftpSession.PendingFileTransfer = new PendingFileTransfer(ftpSession.ClientHost, null, ftpSession.ServerHost, serverListeningOnPort, true, ftpSession);
if (this.pendingFileTransferList.ContainsKey(ftpSession.PendingFileTransfer.GetKey()))
{
this.pendingFileTransferList.Remove(ftpSession.PendingFileTransfer.GetKey());
}
this.pendingFileTransferList.Add(ftpSession.PendingFileTransfer.GetKey(), ftpSession.PendingFileTransfer);
}
}
if (ftpPacket.ResponseCode == 230)//Login successful
//ftpSession.=ftpPacket.RequestArgument;
{
if (ftpSession.Username != null && ftpSession.Password != null)
{
base.MainPacketHandler.AddCredential(new NetworkCredential(tcpSession.ClientHost, tcpSession.ServerHost, ftpPacket.PacketTypeDescription, ftpSession.Username, ftpSession.Password, true, ftpPacket.ParentFrame.Timestamp));
}
}
}//end server to client
}
if (ftpSession != null && ftpSession.PendingFileTransfer != null)
{
//I guess returnValue is already set to true by now, but I'll do it again just to be sure...
returnValue = true;
PendingFileTransfer pending = ftpSession.PendingFileTransfer;
//see if the pending file transfer could be transformed into a real file stream assembler
if (pending.FileTransferSessionEstablished && pending.FileDirectionIsDataSessionServerToDataSessionClient != null && pending.DataSessionClientPort != null)
{
//Server->Client ?
FileTransfer.FileStreamAssembler assembler = null;
if (pending.FileDirectionIsDataSessionServerToDataSessionClient.Value)
{
assembler = new FileTransfer.FileStreamAssembler(MainPacketHandler.FileStreamAssemblerList, pending.DataSessionServer, pending.DataSessionServerPort, pending.DataSessionClient, pending.DataSessionClientPort.Value, true, FileTransfer.FileStreamTypes.FTP, pending.Filename, "/", pending.Details, tcpPacket.ParentFrame.FrameNumber, tcpPacket.ParentFrame.Timestamp);
}
else
{
assembler = new FileTransfer.FileStreamAssembler(MainPacketHandler.FileStreamAssemblerList, pending.DataSessionClient, pending.DataSessionClientPort.Value, pending.DataSessionServer, pending.DataSessionServerPort, true, FileTransfer.FileStreamTypes.FTP, pending.Filename, "/", pending.Details, tcpPacket.ParentFrame.FrameNumber, tcpPacket.ParentFrame.Timestamp);
}
string fileCompletePath = "";
if (assembler.Filename != null && assembler.FileLocation != null)
{
fileCompletePath = assembler.FileLocation + "/" + assembler.Filename;
}
if (ftpSession.FileSizes.ContainsKey(fileCompletePath))
{
assembler.FileContentLength = ftpSession.FileSizes[fileCompletePath];
assembler.FileSegmentRemainingBytes = ftpSession.FileSizes[fileCompletePath];
}
else
{
//-1 is set instead of null if Content-Length is not defined
assembler.FileContentLength = -1;
assembler.FileSegmentRemainingBytes = -1;
}
if (assembler.TryActivate())
{
MainPacketHandler.FileStreamAssemblerList.Add(assembler);
}
//assembler.Activate();
//the file transfer is no longer pending since the assembler is started!
pendingFileTransferList.Remove(pending.GetKey());
ftpSession.PendingFileTransfer = null;
}
}
if (returnValue)
{
return(tcpPacket.PayloadDataLength);
}
else
{
return(0);
}
}
