/// <summary>
/// Control thread
/// TODO: separate the functionalities into functions to reduce maintenance cost
/// </summary>
private void WorkerThread()
{
FtpCommand command;
FtpState state = FtpState.WaitUser;
string tempName = null; // store old name for "rename from" command
string response;
int timeout = 0;
try
{
while (m_IsAlive)
{
if (m_IsDisposed)
{
break;
}
else if (!m_Welcomed)
{
response = "220 MyFTP " + System.Reflection.Assembly.GetExecutingAssembly().GetName().Version.ToString() +
" Server [" + m_HostIp.ToString() + "] \r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
m_Welcomed = true;
}
else if (m_CommandSocket == null)
{
Logging.Print("Session socket has been closed.");
break;
}
else if (m_CommandSocket.Poll(1000, SelectMode.SelectRead))
{
if (m_CommandSocket.Available == 0)
{
Logging.Print("REMOTE DISCONNECT " + m_CommandSocket.RemoteEndPoint.ToString());
m_IsAlive = false;
break;
}
// read until find the end of a line
command = FtpCommandCreator.Create(ReadCommand());
if (command == null)
{
break;
}
else
{
switch (command.Type)
{
case FtpCommandType.User:
response = "331 " + command.Content + " login ok \r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
state = FtpState.WaitPwd;
tempName = command.Content;
break;
case FtpCommandType.Pass:
if (state != FtpState.WaitPwd)
{
response = "332 Need Account for Login.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else
{
UserAuthenticatorArgs args = new UserAuthenticatorArgs(tempName, command.Content);
FtpListener.RaiseEvent(this, args);
if (args.Result == UserAuthenticationResult.Approved)
{
User.UserName = tempName;
User.PassWord = command.Content;
response = "230 access granted for " + User.UserName + ", restrictions apply. \r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
state = FtpState.WaitCommand;
break;
}
else
{
response = "530 Login incorrect. \r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
state = FtpState.WaitCommand;
break;
}
}
case FtpCommandType.Cwd:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitUser)
{
response = "332 Need Account for Login.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
if (command.Content == null)
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else
{
FtpListenerRequest request = new FtpListenerRequest(WebRequestMethodsEx.Ftp.ChangeDirectory, m_CurrentDirectory.Combine(command.Content).GetNetPath(), this);
FtpListenerContext context = new FtpListenerContext(this, request);
m_SendContext.AddContext(context);
break;
}
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Quit:
m_IsAlive = false;
CloseDataChannel();
response = "221 Goodbye.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
m_CommandSocket.Close();
m_CommandSocket = null;
break;
case FtpCommandType.Pasv:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
CloseDataChannel();
m_DataThread = new Thread(PassiveThread);
m_DataThread.Start();
m_DataReadyEvent.WaitOne(); // wait until port has been successfully assigned
byte[] addrs = m_HostIp.GetAddressBytes();
int upper = m_HostPort / 256;
int lower = m_HostPort % 256;
if (addrs.Length == 4) //IPv4
{
response = "227 Entering Passive Mode (";
foreach (int i in addrs)
{
response += i.ToString() + ",";
}
response += upper.ToString() + "," + lower.ToString() + ")\r\n";
}
else // currently do not support IPv6
{
throw new NotImplementedException("currently does not support IPv6");
}
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Type:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
response = "200 Command OK.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.List:
if (!m_DataModeON)
{
response = "425 Use PORT or PASV first.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
response = "150 Opening UTF8 mode data connection for *** \r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
FtpListenerRequest request = new FtpListenerRequest(WebRequestMethods.Ftp.ListDirectoryDetails, m_CurrentDirectory.Combine(command.Content).GetNetPath(), this);
FtpListenerContext context = new FtpListenerContext(this, request);
m_SendContext.AddContext(context);
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.NList:
if (!m_DataModeON)
{
response = "425 Use PORT or PASV first.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
response = "150 Opening UTF8 mode data connection for *** \r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
FtpListenerRequest request = new FtpListenerRequest(WebRequestMethods.Ftp.ListDirectory, m_CurrentDirectory.Combine(command.Content).GetNetPath(), this);
FtpListenerContext context = new FtpListenerContext(this, request);
m_SendContext.AddContext(context);
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Port:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand && command.Content != null)
{
CloseDataChannel();
string[] epad = command.Content.Split(new char[] { ',' });
if (epad.Length != 6)
{
response = "500 Invalid PORT command.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
}
else
{
try
{
m_ClientIp = IPAddress.Parse(epad[0] + "." + epad[1] + "." + epad[2] + "." + epad[3]);
m_ClientPort = Int32.Parse(epad[4]) * 256 + Int32.Parse(epad[5]);
if (m_ClientPort <= 0 || m_ClientPort > 65535)
{
response = "500 Invalid PORT command.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
}
else
{
m_ActThreadW = true;
m_DataThread = new Thread(ActiveThread);
m_DataThread.Start();
response = "200 PORT command successful.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
}
}
catch (Exception)
{
response = "500 Invalid PORT command.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
}
}
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Sys:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
response = "215 System Type: EMIC\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Feature:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
response = "211-Features:\r\n SIZE\r\n211 End\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Pwd:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
response = "257 \"" + m_CurrentDirectory.GetNetPath() + "\" is the current directory. \r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Retr:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
if (!m_DataModeON)
{
response = "425 Use PORT or PASV first.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
response = "150 Opening BINARY mode data connection for " + command.Content + ". \r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
FtpListenerRequest request = new FtpListenerRequest(WebRequestMethods.Ftp.DownloadFile, m_CurrentDirectory.Combine(command.Content).GetNetPath(), this);
FtpListenerContext context = new FtpListenerContext(this, request);
m_SendContext.AddContext(context);
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Opts:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
if (command.Content == "utf8")
{
response = "213 Always in utf8 mode \r\n";
}
else
{
response = "550 Requested action not taken. Mode not support. \r\n";
}
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Size:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
FtpListenerRequest request = new FtpListenerRequest(WebRequestMethods.Ftp.GetFileSize, m_CurrentDirectory.Combine(command.Content).GetNetPath(), this);
FtpListenerContext context = new FtpListenerContext(this, request);
m_SendContext.AddContext(context);
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Store:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
if (!m_DataModeON)
{
response = "425 Use PORT or PASV first.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
response = "150 Opening BINARY mode data connection for " + command.Content + ". \r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
FtpListenerRequest request = new FtpListenerRequest(WebRequestMethods.Ftp.UploadFile, m_CurrentDirectory.Combine(command.Content).GetNetPath(), this);
FtpListenerContext context = new FtpListenerContext(this, request);
m_SendContext.AddContext(context);
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Noop:
response = "200 NOOP command successful. \r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
case FtpCommandType.Delete:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
FtpListenerRequest request = new FtpListenerRequest(WebRequestMethods.Ftp.DeleteFile, m_CurrentDirectory.Combine(command.Content).GetNetPath(), this);
FtpListenerContext context = new FtpListenerContext(this, request);
m_SendContext.AddContext(context);
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.MkDir:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
FtpListenerRequest request = new FtpListenerRequest(WebRequestMethods.Ftp.MakeDirectory, m_CurrentDirectory.Combine(command.Content).GetNetPath(), this);
FtpListenerContext context = new FtpListenerContext(this, request);
m_SendContext.AddContext(context);
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Rmd:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
FtpListenerRequest request = new FtpListenerRequest(WebRequestMethods.Ftp.RemoveDirectory, m_CurrentDirectory.Combine(command.Content).GetNetPath(), this);
FtpListenerContext context = new FtpListenerContext(this, request);
m_SendContext.AddContext(context);
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Rnfr:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
FtpListenerRequest request = new FtpListenerRequest(WebRequestMethodsEx.Ftp.RenameFrom, m_CurrentDirectory.Combine(command.Content).GetNetPath(), this);
FtpListenerContext context = new FtpListenerContext(this, request);
m_SendContext.AddContext(context);
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
case FtpCommandType.Rnto:
if (state == FtpState.WaitPwd)
{
response = "331 Need Password.\r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
else if (state == FtpState.WaitCommand)
{
FtpListenerRequest request = new FtpListenerRequest(WebRequestMethodsEx.Ftp.RenameTo, m_CurrentDirectory.Combine(command.Content).GetNetPath(), this);
FtpListenerContext context = new FtpListenerContext(this, request);
m_SendContext.AddContext(context);
break;
}
else
{
response = m_BadSequence;
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
default:
response = "502 Command not implemented. \r\n";
if (state == FtpState.WaitPwd)
{
state = FtpState.WaitUser;
}
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
break;
}
}
// reset time out
timeout = 0;
}
else if (m_CommandSocket.Poll(1000, SelectMode.SelectError))
{
Logging.Print("Disconnected unproperly.");
break;
}
else
{
if (!m_Welcomed)
{
response = "220 MyFTP " + typeof(FtpListenerSession).Assembly.GetName().Version.ToString() +
" Server [" + m_HostIp.ToString() + "] \r\n";
m_CommandSocket.Send(Encoding.UTF8.GetBytes(response));
m_Welcomed = true;
}
else
{
if (SessionTimeOut != -1)
{
if (timeout > SessionTimeOut)
{
m_IsAlive = false;
Logging.Print("Connection time out.");
break;
}
timeout += 50;
}
Thread.Sleep(50);
}
}
}
}
catch (SocketException se)
{
Logging.Print("Control Socket Exception : " + se.ErrorCode.ToString());
}
catch (IOException ioe)
{
Logging.Print("IOException: " + ioe.Message);
}
finally
{
m_IsAlive = false;
if (m_CommandSocket != null)
{
m_CommandSocket.Close();
m_CommandSocket = null;
}
if (m_ListenSocket != null)
{
m_ListenSocket.Close();
m_CommandSocket = null;
}
Logging.Print("Client Disconnected.");
}
}