public static void Run()
{
DHCPPacket dh = new DHCPPacket(DHCPdata);
TFTPPacketReadReq pp = new TFTPPacketReadReq(TFTPReqData);
TFTPPacketError err = new TFTPPacketError(TFTPErrorData);
}
public bool Data(IPAddress client, int Port, byte[] data)
{
if (RunningSessions.ContainsKey(client) == false)
{
SessionData nses = new SessionData();
nses.Architecture = DHCPArchitecture.Undefined;
nses.IP = client;
nses.TFTPRootPath = Settings.TFTPRootPath + "Unknown\\";
lock (RunningSessions)
RunningSessions.Add(client, nses);
}
SessionData ses = RunningSessions[client];
if (data.Length < 2)
{
TFTPPacketError err = new TFTPPacketError(TFTPErrorCode.IllegalTFTPOP, "Illegal TFTP OP");
ses.SendData(Port, client, err.GetBytes);
return(false);
}
TFTPOpcode opcode = (TFTPOpcode)(((int)data[0] * 0x100) + ((int)data[1] * 0x1));
switch (opcode)
{
case TFTPOpcode.Read:
{
TFTPPacketReadReq rr = new TFTPPacketReadReq(data);
if (rr.Malformed == true)
{
TFTPPacketError err = new TFTPPacketError(TFTPErrorCode.IllegalTFTPOP, "Malformed packet");
ses.SendData(Port, client, err.GetBytes);
return(false);
}
if (string.IsNullOrWhiteSpace(rr.Filename) == true)
{
rr.Filename = ses.currentfilename;
}
if (string.IsNullOrWhiteSpace(rr.Filename) == true)
{
TFTPPacketError err = new TFTPPacketError(TFTPErrorCode.IllegalTFTPOP, "Malformed packet");
ses.SendData(Port, client, err.GetBytes);
return(false);
}
ses.LastUpdated = DateTime.Now;
if (ses.currentfile != null)
{
ses.currentfile.Close();
}
ses.currentfile = null;
ses.datatosend = null;
ses.OpenACK = false;
ses.currentfilename = rr.Filename;
Console.WriteLine(client.ToString() + "(" + ses.Architecture.ToString() + ") requesting file: " + rr.Filename);
rr.Filename = rr.Filename.Replace("/", "\\");
if (rr.Filename.StartsWith("\\") == true)
{
rr.Filename = rr.Filename.Substring(1, rr.Filename.Length - 1);
}
if (rr.Filename.EndsWith("\\") == true)
{
TFTPPacketError err = new TFTPPacketError(TFTPErrorCode.FileNotFound, "Invalid path");
ses.SendData(Port, client, err.GetBytes);
return(false);
}
if (File.Exists(ses.TFTPRootPath + rr.Filename) == false)
{
TFTPPacketError err = new TFTPPacketError(TFTPErrorCode.FileNotFound, "File does not exist");
ses.SendData(Port, client, err.GetBytes);
return(false);
}
ses.currentfile = File.Open(ses.TFTPRootPath + rr.Filename, FileMode.Open, FileAccess.Read, FileShare.Read);
ses.blksize = rr.blksize == null ? 512 : rr.blksize.Value;
if (ses.blksize > 1468)
{
ses.blksize = 1468;
}
ses.Sequence = null;
ses.CurrentPos = 0;
FileInfo info = new FileInfo(ses.TFTPRootPath + rr.Filename);
ses.TotalSize = info.Length;
ses.windowsize = rr.windowsize == null ? 1 : rr.windowsize.Value;
List <string> Options = new List <string>();
if (rr.blksize != null)
{
Options.Add("blksize");
Options.Add(ses.blksize.ToString());
}
if (rr.tsize != null)
{
Options.Add("tsize");
Options.Add(info.Length.ToString());
}
if (rr.windowsize != null)
{
Options.Add("windowsize");
Options.Add(ses.windowsize.ToString());
}
TFTPPacketOptAck oack = new TFTPPacketOptAck(Options);
ses.OpenACK = true;
ses.SendData(Port, client, oack.GetBytes);
Console.WriteLine(client.ToString() + "(" + ses.Architecture.ToString() + ") got file: " + ses.TFTPRootPath + rr.Filename);
break;
}
case TFTPOpcode.Write:
{
TFTPPacketError err = new TFTPPacketError(TFTPErrorCode.AccessViolation, "Writing not supported");
ses.SendData(Port, client, err.GetBytes);
break;
}
case TFTPOpcode.Error:
{
ses.LastUpdated = DateTime.Now;
if (ses.currentfile != null)
{
ses.currentfile.Close();
}
ses.currentfile = null;
ses.datatosend = null;
ses.OpenACK = false;
Console.WriteLine(client.ToString() + "(" + ses.Architecture.ToString() + ") got error from client");
break;
}
case TFTPOpcode.Ack:
{
TFTPPacketClientAck ack = new TFTPPacketClientAck(data);
if (ack.Malformed == true)
{
TFTPPacketError err = new TFTPPacketError(TFTPErrorCode.IllegalTFTPOP, "Malformed packet");
ses.SendData(69, client, err.GetBytes);
return(false);
}
ses.LastUpdated = DateTime.Now;
if (ses.Sequence == null)
{
ses.Sequence = ack.Ack;
}
if (ack.Ack < ses.Sequence)
{
return(true);
}
if (ack.Ack != ses.Sequence)
{
TFTPPacketError err = new TFTPPacketError(TFTPErrorCode.IllegalTFTPOP, "Invalid sequence");
ses.SendData(Port, client, err.GetBytes);
ses.LastSend = DateTime.Now;
return(false);
}
ses.datatosend = new List <byte[]>();
long Read = ses.blksize;
for (int i = 0; i < ses.windowsize; i++)
{
ses.LastSend = DateTime.Now;
if (ses.CurrentPos + Read > ses.TotalSize)
{
Read = ses.TotalSize - ses.CurrentPos;
}
if (Read == 0)
{
break;
}
else
{
byte[] filedata = new byte[Read];
ses.currentfile.Read(filedata, 0, (int)Read);
ses.Sequence++;
TFTPData d = new TFTPData(ses.Sequence.Value, filedata);
ses.OpenACK = true;
ses.LastSend = DateTime.Now;
ses.datatosendport = Port;
ses.CurrentPos += Read;
ses.datatosend.Add(d.GetBytes);
}
}
foreach (byte[] b in ses.datatosend)
{
ses.SendData(Port, client, b);
}
if (Read == 0)
{
ses.OpenACK = false;
ses.datatosend = null;
ses.LastSend = DateTime.Now;
}
break;
}
default:
{
TFTPPacketError err = new TFTPPacketError(TFTPErrorCode.NotDefined, "Not defined OP " + opcode.ToString());
ses.SendData(Port, client, err.GetBytes);
ses.OpenACK = false;
return(false);
}
}
return(true);
}