Gist by paste.py @ 2014-11-02 01:28:06.038742

smtp.py

#!/usr/bin/python3

import sys
import threading
import socket
import time

def usage():
	print('Usage:', sys.argv[0], '[Threads]')

class err(Exception):
	pass

def getline(socket):
	ch = ' '
	buff = ''.encode("ascii")
	first = True
	#sys.stderr.write('Debug:')
	while True:
		ch = socket.recv(1)
		#sys.stderr.write(str(ch))
		if len(ch) == 0 and first:
			raise err
		first = False
		if ch == '\n'.encode("ascii") or len(ch) == 0:
			break
		elif ch == '\r'.encode("ascii"):
			socket.recv(1)
			break
		else:
			buff = buff + ch
	if first and len(ch) == 0:
		raise err
	print('Client:', buff)
	return buff

class Queue(object):
	def __init__(self):
		self.data = []
		self.flag = False
	def get(self):
		while self.flag:
			time.sleep(0.05)
		self.flag = True
		try:
			t = self.data[0]
			del self.data[0]
			self.flag = False
			return t
		except:
			self.flag = False
			return False
	def put(self, obj):
		while self.flag:
			time.sleep(0.05)
		self.flag = True
		self.data.append(obj)
		self.flag = False
	def empty(self):
		return len(self.data) == 0
	def size(self):
		return len(self.data)

class Server(object):
	def __init__(self, port = 25, thread = 10):
		self.thread = thread
		self.filebase = '/home/mails/'
		print('Server Loading...')
		self.ssock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
		self.ssock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
		try:
			self.ssock.bind(('', port))
		except:
			print('Unable to bind to port', port, ',somebody is using this port?')
			exit()
		print('Bind to port', port, 'successfully')
		self.ssock.listen(thread * 2)
		print('Start listening on port', port)
		self.running = True
	def mainThread(self):
		self.connection = Queue()
		self.threads = []
		print('Starting', server.thread, 'thread(s)...')
		for _ in range(1, self.thread + 1):
			self.threads.append(threading.Thread(target = self.processThread, args = (_, )))
			self.threads[_ - 1].start()
		print('Threads started.')
		while self.running:
			try:
				(conn, addr) = self.ssock.accept()
			except:
				exit()
			self.connection.put(conn)
			print('['+addr[0]+':'+str(addr[1])+'] connected, awaiting process...')
			print('Currently Load: '+str(self.connection.size())+' connection pending')
	def processUnit(self, socket):
		socket.sendall('220 labs.jackyyf.com SMTP Server Ready\r\n'.encode('ascii'))
		print('Server: 220 labs.jackyyf.com SMTP Server Ready')
		try:
			st = getline(socket)
		except err:
			return True
		try:
			lst = st.split(' '.encode("ascii"), 1)
			command = lst[0].upper()
			domain = lst[1]
		except:
			domain = ''.encode("ascii")
			command = st.upper()
		if (command != 'EHLO'.encode("ascii")) and (command != 'HELO'.encode("ascii")):
			print(command)
			return True
		socket.send('250 labs.jackyyf.com greets '.encode('ascii') + domain + '\r\n'.encode('ascii'))
		print('Server:', '250 labs.jackyyf.com greets '.encode('ascii') + domain + '\r\n'.encode('ascii'))
		while True:
			try:
				st = getline(socket)
			except err:
				break
			try:
				lst = st.split(' '.encode("ascii"), 1)
				command = lst[0].upper()
			except:
				command = st.upper()
			if len(command) == 0:
				continue
			if command == 'QUIT'.encode("ascii") or command == b'RSET':
				break
			elif command == 'RCPT'.encode("ascii"):
				socket.sendall('250 OK\r\n'.encode('ascii'))
				print('Server: 250 OK')
			elif command == 'MAIL'.encode("ascii"):
				socket.sendall('250 OK\r\n'.encode('ascii'))
				print('Server: 250 OK')
				continue
			elif command == 'DATA'.encode("ascii"):
				socket.sendall('354 End Transmission with <CRLF>.<CRLF>\r\n'.encode('ascii'))
				print('Server: 354 End Transmission with <CRLF>.<CRLF>')
				try:
					cntf = open(self.filebase + '.cnt', 'r')
					cnt = int(cntf.readline()) + 1
					cntf.close()
					cntf = open(self.filebase + '.cnt', 'w')
					cntf.write(str(cnt))
					cntf.close()
				except:
					cnt = 0
					cntf = open(self.filebase + '.cnt', 'w')
					cntf.write(str(cnt))
					cntf.close()
				f = open(self.filebase + str(cnt), 'wb')
				while True:
					line = getline(socket)
					if line == b'.':
						f.close()
						socket.sendall('250 Saved\r\n'.encode('ascii'))
						print('Server: 250 Saved')
						return True
						break
					f.write(line+'\n'.encode('utf-8'))
			else :
				socket.sendall('500 Error...\r\n'.encode('ascii'))
				print('Server: 500 Error...')
				break
		socket.sendall('221 Goodbye.\r\n'.encode('ascii'))
		print('Server 221 Goodbye.')
		return True

	def processThread(self, pid):
		while self.running:
			if self.connection.empty():
				time.sleep(0.5)
			else:
				socket = self.connection.get()
				if not socket:
					continue
				print('Thread', pid, 'processing...')
				while not(self.processUnit(socket)):
					continue
				socket.close()
				print('Thread', pid, 'finished.')
	def close(self):
		print('Server shutting down...')
		self.running = False
		self.ssock.close()
	
if __name__ == '__main__':
	if len(sys.argv) == 2:
		try:
			threadcnt = int(sys.argv[1]);
		except:
			usage()
			exit()
		if str(threadcnt) != sys.argv[1]:
			usage()
			exit()
	elif len(sys.argv) > 2:
		usage()
		exit()
	else:
		threadcnt = 10
		print('Will use 10 threads as default.')
	server = Server(thread = threadcnt)
	serverThread = threading.Thread(target = server.mainThread)
	serverThread.start()
	while 1:
		command = input().strip().upper()
		if command == 'SHUTDOWN' or command == 'STOP':
			server.close()
			time.sleep(0.5)
			exit()