Fakeftp server

fakeftp.py

@@ -0,0 +1,117 @@
+import SocketServer
+
+class FTPMessage:
+	def __init__(self,cmd,parameter):
+		self.cmd = cmd
+		self.parameter = parameter
+
+	def generate(self):
+		return "%s %s\r\n" % (self.cmd.upper(), self.parameter)
+
+	def __str__(self):
+		return self.generate()
+
+	@staticmethod
+	def parse(line):
+		pos = line.find(" ")
+		if pos == -1:
+			cmd = line
+			param = None
+		else:
+			cmd = line[:pos]
+			param = line[pos+1:]
+		return FTPMessage(cmd.upper(),param)
+
+class GeneralState:
+	@staticmethod
+	def handle(self, message):
+		if message.cmd == "QUIT":
+			self.debug("Client wants to quit")
+			self.send(FTPMessage("221","Goodbye."))
+			self.handler.running = False
+		else:
+			self.debug("Unknown command %s" % message.cmd)
+			self.send(FTPMessage("500", "%s not understood" % message.cmd ))
+
+class UserState:
+	@staticmethod
+	def handle(self, message):
+		if message.cmd == "USER":
+			self.debug("Initiating login for user %s" % message.parameter)
+			self.send(FTPMessage("331","Password required for %s" % message.parameter))
+			self.state = PassState
+		else:
+			GeneralState.handle(self, message)
+
+class PassState:
+	@staticmethod
+	def handle(self, message):
+		if message.cmd == "PASS":
+			self.debug("Denying access with password %s" % message.parameter)
+			self.send(FTPMessage("530","Login incorrect."))
+			self.state = UserState
+		else:
+			GeneralState.handle(self, message)
+
+class FTPMessageHandler:
+	def __init__(self, handler):
+		self.state = UserState
+		self.handler = handler
+
+	def send(self,data):
+		return self.handler.request.send( str(data) )
+
+	def debug(self,text):
+		self.handler.debug(text)
+
+	def handle(self, message):
+		self.state.handle(self, message)
+
+class LineReader:
+	def __init__(self):
+		self.buf = ""
+
+	def push(self,data):
+		self.buf += data
+
+	def get_lines(self):
+		pos = self.buf.find("\n")
+		while pos != -1:
+			line = self.buf[:pos]
+			if line[-1] == "\r":
+				line = line[:-2]
+			yield line
+			self.buf = self.buf[pos+1:]
+			pos = self.buf.find("\n")
+
+class FTPHandler(SocketServer.BaseRequestHandler):
+	def debug(self, text):
+		print ("[%s] " % self.client_address[0]) + text
+
+	def handle(self):
+		self.messagehandler = FTPMessageHandler(self)
+
+		self.debug("Client connected");
+
+		self.request.send(FTPMessage("220","FTP Server ready").generate())
+
+		linereader = LineReader()
+
+		self.running = True
+
+		while self.running:
+			data = self.request.recv(1024)
+			if len(data) == 0:
+				break
+
+			linereader.push(data)
+
+			for line in linereader.get_lines():
+				message = FTPMessage.parse(line)
+				self.messagehandler.handle(message)
+
+		self.debug("Client disconnected")
+
+server = SocketServer.ThreadingTCPServer(("",1234),FTPHandler)
+
+server.serve_forever()