/// <summary>
/// Process FTP commands when the user is not yet logged in.
/// Mostly handles the login commands USER and PASS.
/// </summary>
private void HandleAuth(string verb, string args)
{
if (verb == "USER" && args != null)
{
if (authHandler.AllowLogin(args, null, password))
{
Respond(230, "Login successful.");
loggedIn = true;
}
else
{
loggedInUser = args;
Respond(331, "Password please.");
}
}
else if (verb == "PASS")
{
if (loggedInUser != null)
{
if (authHandler.AllowLogin(loggedInUser, args, password))
{
Respond(230, "Login successful.");
loggedIn = true;
}
else
{
loggedInUser = null;
Respond(530, "Login failed, please try again.");
}
}
else
{
Respond(530, "No USER specified.");
}
}
else
{
Respond(530, "Please login first.");
}
}
/// <summary>
/// Main method of the session thread.
/// Reads commands and executes them.
/// </summary>
private void Work()
{
if (logHandler != null)
{
logHandler.NewControlConnection();
}
try {
if (!authHandler.AllowControlConnection())
{
Respond(421, "Control connection refused.");
// first flush, then close
controlSocket.Shutdown(SocketShutdown.Both);
controlSocket.Close();
return;
}
Respond(220, String.Format("This is mooftpserv v{0}. {1}", LIB_VERSION, GetRandomText(HELLO_TEXT)));
// allow anonymous login?
if (authHandler.AllowLogin(null, null))
{
loggedIn = true;
}
while (controlSocket.Connected)
{
string verb;
string args;
if (!ReadCommand(out verb, out args))
{
if (controlSocket.Connected)
{
// assume clean disconnect if there are no buffered bytes
if (cmdRcvBytes != 0)
{
Respond(500, "Failed to read command, closing connection.");
}
controlSocket.Close();
}
break;
}
else if (verb.Trim() == "")
{
// ignore empty lines
continue;
}
try {
if (loggedIn)
{
ProcessCommand(verb, args);
}
else if (verb == "QUIT") // QUIT should always be allowed
{
Respond(221, "Bye.");
// first flush, then close
controlSocket.Shutdown(SocketShutdown.Both);
controlSocket.Close();
}
else
{
HandleAuth(verb, args);
}
} catch (Exception ex) {
Respond(500, ex);
}
}
} catch (Exception) {
// catch any uncaught stuff, the server should not throw anything
} finally {
if (controlSocket.Connected)
{
controlSocket.Close();
}
if (logHandler != null)
{
logHandler.ClosedControlConnection();
}
threadAlive = false;
}
}
