diff --git a/newclient.py b/newclient.py
index 0dac576..9c8a15f 100644
--- a/newclient.py
+++ b/newclient.py
@@ -1,385 +1,331 @@
-#!/usr/bin/env python
+#! /usr/bin/env python
 # -*- coding: utf-8 -*-
-import socket, struct, time
+
+import socket, struct, random, time, re, os, datetime
 from hashlib import md5
-import sys
-import os
-import random
 
-# CONFIG
+########## Configuration ###############
+
+### Required ###
+username='USERNAME'  #用户名
+password='PASSWORD'  #密码
+host_ip = 'IP_ADDR'  #ip地址
+mac = 0x010203040506 #mac地址 echo 0x`ifconfig eth | egrep -io "([0-9a-f]{2}:){5}[0-9a-f]{2}" | tr -d ":"`
+
+### Optional ###
+host_name = '++++++++' #计算机名
+host_os = 'Windows XP' #操作系统
+bind_ip = '0.0.0.0'    #must be listed in your `ip a` results
+LOG_PATH = '/var/log/drcom.log'
+RETRY = False
+
+### for Development ###
+IS_DEBUG=False
+
 server = '10.100.61.3'
-username='#@#@#@#@#@'#用户名
-password='@###@#@#@#'#密码
-host_ip = '202.198.171.190'#ip地址
-mac = 0x888888888888#mac地址
-host_name = '++++++++'#计算机名
-host_os = 'Windows 10'#操作系统
+
+#used in mkpkt()
 CONTROLCHECKSTATUS = '\x20'
 ADAPTERNUM = '\x03'
 IPDOG = '\x01'
 PRIMARY_DNS = '10.10.10.10'
 dhcp_server = '0.0.0.0'
 AUTH_VERSION = '\x68\x00'
+
+# used in keep_alive
 KEEP_ALIVE_VERSION = '\xdc\x02'
-# CONFIG_END
+############## END #####################
 
-nic_name = '' #Indicate your nic, e.g. 'eth0.2'.nic_name
-bind_ip = '0.0.0.0'
+class LoginException (Exception):
+  def __init__(self):
+    pass
 
-class ChallengeException (Exception):
-    def __init__(self):
-        pass
+def setup_socket(bind_ip):
+  log('DEBUG', 'setup_socket()')
+  s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+  # s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+  s.bind((bind_ip, 61440))
+  s.settimeout(3)
+  return s
 
-class LoginException (Exception):
-    def __init__(self):
-        pass
 
-def bind_nic():
-    try:
-        import fcntl
-        def get_ip_address(ifname):
-            s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
-            return socket.inet_ntoa(fcntl.ioctl(
-                s.fileno(),
-                0x8915,  # SIOCGIFADDR
-                struct.pack('256s', ifname[:15])
-            )[20:24])
-        return get_ip_address(nic_name)
-    except ImportError as e:
-        print('Indicate nic feature need to be run under Unix based system.')
-        return '0.0.0.0'
-    except IOError as e:
-        print(nic_name + 'is unacceptable !')
-        return '0.0.0.0'
-    finally:
-        return '0.0.0.0'
-
-if nic_name != '':
-    bind_ip = bind_nic()
-
-s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
-# s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
-s.bind((bind_ip, 61440))
-
-s.settimeout(3)
-SALT = ''
-IS_TEST = True
-# specified fields based on version
-CONF = "/etc/drcom.conf"
-UNLIMITED_RETRY = True
-EXCEPTION = False
-DEBUG = False #log saves to file
-LOG_PATH = '/var/log/drcom_client.log'
-if IS_TEST:
-    DEBUG = True
-    LOG_PATH = 'drcom_client.log'
-
-
-def log(*args, **kwargs):
-    s = ' '.join(args)
-    print s
-    if DEBUG:
-        with open(LOG_PATH,'a') as f:
-            f.write(s + '\n')
-
-def challenge(svr,ran):
-    while True:
-        t = struct.pack("<H", int(ran)%(0xFFFF))
-        s.sendto("\x01\x02"+t+"\x09"+"\x00"*15, (svr, 61440))
-        try:
-            data, address = s.recvfrom(1024)
-            log('[challenge] recv',data.encode('hex'))
-        except:
-            log('[challenge] timeout, retrying...')
-            continue
-        
-        if address == (svr, 61440):
-            break
-        else:
-            continue
-    log('[DEBUG] challenge:\n' + data.encode('hex'))
-    if data[0] != '\x02':
-        raise ChallengeException
-    log('[challenge] challenge packet sent.')
-    return data[4:8]
-
-def md5sum(s):
-    m = md5()
-    m.update(s)
-    return m.digest()
+def do_login(user, pwd, salt, mac, svr, socket):
+  log('DEBUG', 'do_login()')
+  packet = mkpkt(salt, user, pwd, mac)
+  log('DEBUG', '[login] send:' + packet.encode('hex'))
+  socket.sendto(packet, (svr, 61440))
+  data, address = socket.recvfrom(1024)
+  log('DEBUG', '[login] recv:' + data.encode('hex'))
+  if address == (svr, 61440):
+    if data[0] == '\x04':
+      log('INFO', 'auth success.')
+    else:
+      log('WARN', 'auth failed.')
+      raise LoginException
+  else:
+    log('WARN', 'exception occured. address not match')
+    raise Exception
+            
+  #0.8 changed:
+  return data[23:39]
+  #return data[-22:-6]
+
+
+def get_salt(socket, svr, rand):
+  log('DEBUG', 'get_salt()')
+  t = struct.pack("<H", int(rand)%(0xFFFF))
+  socket.sendto("\x01\x02"+t+"\x09"+"\x00"*15, (svr, 61440))
+  log('DEBUG', 'send: blabla ')
+  data, address = socket.recvfrom(1024)
+  log('DEBUG', 'sending:' + data.encode('hex'))
+  if data[0] != '\x02':
+    raise Exception
+  return data[4:8]
+
+
+def mkpkt(salt, usr, pwd, mac):
+  log('DEBUG', 'mkpkt()')
+  data = '\x03\x01\x00'+chr(len(usr)+20)
+  data += md5sum('\x03\x01'+salt+pwd)
+  data += usr.ljust(36, '\x00')
+  data += CONTROLCHECKSTATUS
+  data += ADAPTERNUM
+  data += dump(int(data[4:10].encode('hex'),16)^mac).rjust(6,'\x00') #mac xor md51
+  data += md5sum("\x01" + pwd + salt + '\x00'*4) #md52
+  data += '\x01' # number of ip
+  #data += '\x0a\x1e\x16\x11' #your ip address1, 10.30.22.17
+  data += ''.join([chr(int(i)) for i in host_ip.split('.')]) #x.x.x.x -> 
+  data += '\00'*4 #your ipaddress 2
+  data += '\00'*4 #your ipaddress 3
+  data += '\00'*4 #your ipaddress 4
+  data += md5sum(data + '\x14\x00\x07\x0b')[:8] #md53
+  data += IPDOG
+  data += '\x00'*4 #delimeter
+  data += host_name.ljust(32, '\x00')
+  data += ''.join([chr(int(i)) for i in PRIMARY_DNS.split('.')]) #primary dns
+  data += ''.join([chr(int(i)) for i in dhcp_server.split('.')]) #DHCP server
+  data += '\x00\x00\x00\x00' #secondary dns:0.0.0.0
+  data += '\x00' * 8 #delimeter
+  data += '\x94\x00\x00\x00' # unknow
+  data += '\x06\x00\x00\x00' # os major
+  data += '\x02\x00\x00\x00' # os minor
+  data += '\xf0\x23\x00\x00' # OS build
+  data += '\x02\x00\x00\x00' #os unknown
+  data += '\x44\x72\x43\x4f\x4d\x00\xcf\x07\x68'
+  data += '\x00' * 55#unknown string
+  data += '\x33\x64\x63\x37\x39\x66\x35\x32\x31\x32\x65\x38\x31\x37\x30\x61\x63\x66\x61\x39\x65\x63\x39\x35\x66\x31\x64\x37\x34\x39\x31\x36\x35\x34\x32\x62\x65\x37\x62\x31'
+  data += '\x00' * 24
+  data += AUTH_VERSION
+  data += '\x00' + chr(len(pwd))
+  data += ror(md5sum('\x03\x01'+salt+pwd), pwd)
+  data += '\x02\x0c'
+  data += checksum(data+'\x01\x26\x07\x11\x00\x00'+dump(mac))
+  data += '\x00\x00' #delimeter
+  data += dump(mac)
+  if (len(pwd) / 4) != 4:
+    data += '\x00' * (len(pwd) / 4)#strange。。。
+  data += '\x60\xa2' #unknown, filled numbers randomly =w=
+  data += '\x00' * 28
+  return data
+
+
+def md5sum(str):
+  log('DEBUG', 'md5sum()')
+  m = md5()
+  m.update(str)
+  return m.digest()
+
 
 def dump(n):
-    s = '%x' % n
-    if len(s) & 1:
-        s = '0' + s
-    return s.decode('hex')
+  log('DEBUG', 'dump()')
+  s = '%x' % n
+  if len(s) & 1:
+    s = '0' + s
+  return s.decode('hex')
+
 
 def ror(md5, pwd):
-    ret = ''
-    for i in range(len(pwd)):
-        x = ord(md5[i]) ^ ord(pwd[i])
-        ret += chr(((x<<3)&0xFF) + (x>>5))
-    return ret
-
-def keep_alive_package_builder(number,random,tail,type=1,first=False):
-    data = '\x07'+ chr(number) + '\x28\x00\x0b' + chr(type)
-    if first :
-        data += '\x0f\x27'
-    else:
-        data += KEEP_ALIVE_VERSION
-    data += '\x2f\x12' + '\x00' * 6
-    data += tail
-    data += '\x00' * 4
-    #data += struct.pack("!H",0xdc02)
-    if type == 3:
-        foo = ''.join([chr(int(i)) for i in host_ip.split('.')]) # host_ip
-        #CRC
-        # edited on 2014/5/12, filled zeros to checksum
-        # crc = packet_CRC(data+foo)
-        crc = '\x00' * 4
-        #data += struct.pack("!I",crc) + foo + '\x00' * 8
-        data += crc + foo + '\x00' * 8
-    else: #packet type = 1
-        data += '\x00' * 16
-    return data
-
-# def packet_CRC(s):
-#     ret = 0
-#     for i in re.findall('..', s):
-#         ret ^= struct.unpack('>h', i)[0]
-#         ret &= 0xFFFF
-#     ret = ret * 0x2c7
-#     return ret
-
-def keep_alive2(*args):
-    #first keep_alive:
-    #number = number (mod 7)
-    #status = 1: first packet user sended
-    #         2: first packet user recieved
-    #         3: 2nd packet user sended
-    #         4: 2nd packet user recieved
-    #   Codes for test
-    tail = ''
-    packet = ''
-    svr = server
-    ran = random.randint(0,0xFFFF)
-    ran += random.randint(1,10)   
-    # 2014/10/15 add by latyas, maybe svr sends back a file packet
-    svr_num = 0
-    packet = keep_alive_package_builder(svr_num,dump(ran),'\x00'*4,1,True)
-    while True:
-        log('[keep-alive2] send1',packet.encode('hex'))
-        s.sendto(packet, (svr, 61440))
-        data, address = s.recvfrom(1024)
-        log('[keep-alive2] recv1',data.encode('hex'))
-        if data.startswith('\x07\x00\x28\x00') or data.startswith('\x07' + chr(svr_num)  + '\x28\x00'):
-            break
-        elif data[0] == '\x07' and data[2] == '\x10':
-            log('[keep-alive2] recv file, resending..')
-            svr_num = svr_num + 1
-            packet = keep_alive_package_builder(svr_num,dump(ran),'\x00'*4,1, False)
-        else:
-            log('[keep-alive2] recv1/unexpected',data.encode('hex'))
-    #log('[keep-alive2] recv1',data.encode('hex'))
-    
-    ran += random.randint(1,10)   
-    packet = keep_alive_package_builder(svr_num, dump(ran),'\x00'*4,1,False)
-    log('[keep-alive2] send2',packet.encode('hex'))
-    s.sendto(packet, (svr, 61440))
-    while True:
-        data, address = s.recvfrom(1024)
-        if data[0] == '\x07':
-            svr_num = svr_num + 1
-            break
-        else:
-            log('[keep-alive2] recv2/unexpected',data.encode('hex'))
-    log('[keep-alive2] recv2',data.encode('hex'))
-    tail = data[16:20]
-    
-
-    ran += random.randint(1,10)   
-    packet = keep_alive_package_builder(svr_num,dump(ran),tail,3,False)
-    log('[keep-alive2] send3',packet.encode('hex'))
-    s.sendto(packet, (svr, 61440))
-    while True:
-        data, address = s.recvfrom(1024)
-        if data[0] == '\x07':
-            svr_num = svr_num + 1
-            break
-        else:
-            log('[keep-alive2] recv3/unexpected',data.encode('hex'))
-    log('[keep-alive2] recv3',data.encode('hex'))
-    tail = data[16:20]
-    log("[keep-alive2] keep-alive2 loop was in daemon.")
-    
-    i = svr_num
-    while True:
-        try:
-            ran += random.randint(1,10)   
-            packet = keep_alive_package_builder(i,dump(ran),tail,1,False)
-            #log('DEBUG: keep_alive2,packet 4\n',packet.encode('hex'))
-            log('[keep_alive2] send',str(i),packet.encode('hex'))
-            s.sendto(packet, (svr, 61440))
-            data, address = s.recvfrom(1024)
-            log('[keep_alive2] recv',data.encode('hex'))
-            tail = data[16:20]
-            #log('DEBUG: keep_alive2,packet 4 return\n',data.encode('hex'))
-        
-            ran += random.randint(1,10)   
-            packet = keep_alive_package_builder(i+1,dump(ran),tail,3,False)
-            #log('DEBUG: keep_alive2,packet 5\n',packet.encode('hex'))
-            s.sendto(packet, (svr, 61440))
-            log('[keep_alive2] send',str(i+1),packet.encode('hex'))
-            data, address = s.recvfrom(1024)
-            log('[keep_alive2] recv',data.encode('hex'))
-            tail = data[16:20]
-            #log('DEBUG: keep_alive2,packet 5 return\n',data.encode('hex'))
-            i = (i+2) % 0xFF
-            time.sleep(20)
-            keep_alive1(*args)
-        except:
-            pass
-
-    
-import re
+  log('DEBUG', 'ror()')
+  ret = ''
+  for i in range(len(pwd)):
+    x = ord(md5[i]) ^ ord(pwd[i])
+    ret += chr(((x<<3)&0xFF) + (x>>5))
+  return ret
+
+
 def checksum(s):
-    ret = 1234
-    for i in re.findall('....', s):
-        ret ^= int(i[::-1].encode('hex'), 16)
-    ret = (1968 * ret) & 0xffffffff
-    return struct.pack('<I', ret)
+  log('DEBUG', 'checksum()')
+  ret = 1234
+  for i in re.findall('....', s):
+    ret ^= int(i[::-1].encode('hex'), 16)
+  ret = (1968 * ret) & 0xffffffff
+  return struct.pack('<I', ret)
 
-def mkpkt(salt, usr, pwd, mac):
-    data = '\x03\x01\x00'+chr(len(usr)+20)
-    data += md5sum('\x03\x01'+salt+pwd)
-    data += usr.ljust(36, '\x00')
-    data += CONTROLCHECKSTATUS
-    data += ADAPTERNUM
-    data += dump(int(data[4:10].encode('hex'),16)^mac).rjust(6,'\x00') #mac xor md51
-    data += md5sum("\x01" + pwd + salt + '\x00'*4) #md52
-    data += '\x01' # number of ip
-    #data += '\x0a\x1e\x16\x11' #your ip address1, 10.30.22.17
-    data += ''.join([chr(int(i)) for i in host_ip.split('.')]) #x.x.x.x -> 
-    data += '\00'*4 #your ipaddress 2
-    data += '\00'*4 #your ipaddress 3
-    data += '\00'*4 #your ipaddress 4
-    data += md5sum(data + '\x14\x00\x07\x0b')[:8] #md53
-    data += IPDOG
-    data += '\x00'*4 #delimeter
-    data += host_name.ljust(32, '\x00')
-    data += ''.join([chr(int(i)) for i in PRIMARY_DNS.split('.')]) #primary dns
-    data += ''.join([chr(int(i)) for i in dhcp_server.split('.')]) #DHCP server
-    data += '\x00\x00\x00\x00' #secondary dns:0.0.0.0
-    data += '\x00' * 8 #delimeter
-    data += '\x94\x00\x00\x00' # unknow
-    data += '\x06\x00\x00\x00' # os major
-    data += '\x02\x00\x00\x00' # os minor
-    data += '\xf0\x23\x00\x00' # OS build
-    data += '\x02\x00\x00\x00' #os unknown
-    data += '\x44\x72\x43\x4f\x4d\x00\xcf\x07\x68'
-    data += '\x00' * 55#unknown string
-    data += '\x33\x64\x63\x37\x39\x66\x35\x32\x31\x32\x65\x38\x31\x37\x30\x61\x63\x66\x61\x39\x65\x63\x39\x35\x66\x31\x64\x37\x34\x39\x31\x36\x35\x34\x32\x62\x65\x37\x62\x31'
-    data += '\x00' * 24
-    data += AUTH_VERSION
-    data += '\x00' + chr(len(pwd))
-    data += ror(md5sum('\x03\x01'+salt+pwd), pwd)
-    data += '\x02\x0c'
-    data += checksum(data+'\x01\x26\x07\x11\x00\x00'+dump(mac))
-    data += '\x00\x00' #delimeter
-    data += dump(mac)
-    if (len(pwd) / 4) != 4:
-        data += '\x00' * (len(pwd) / 4)#strange。。。
-    data += '\x60\xa2' #unknown, filled numbers randomly =w=
-    data += '\x00' * 28
-    log('[mkpkt]',data.encode('hex'))
-    return data
-
-def login(usr, pwd, svr):
-    import random
-    global SALT
+
+def keep_alive(pwd, salt, cookie, svr, socket):
+  log('DEBUG', 'keep_alive')
+  old_cookie = cookie
+  keep_alive1(salt, old_cookie, pwd, svr, socket)
+
+  svr_num = 0
+
+  svr_num, cookie = keep_alive_pre_1(svr_num, cookie, svr, socket)
+  svr_num, cookie = keep_alive_pre_2(svr_num, cookie, svr, socket)
+  svr_num, cookie = keep_alive_pre_3(svr_num, cookie, svr, socket)
+
+  i = svr_num
+  while True:
+    packet = keep_alive_package_builder(i, cookie, 1, False)
+    socket.sendto(packet, (svr, 61440))
+    data, address = socket.recvfrom(1024)
+    cookie = data[16:20]
  
-    i = 0
-    while True:
-        salt = challenge(svr,time.time()+random.randint(0xF,0xFF))
-        SALT = salt
-        packet = mkpkt(salt, usr, pwd, mac)
-        log('[login] send',packet.encode('hex'))
-        s.sendto(packet, (svr, 61440))
-        data, address = s.recvfrom(1024)
-        log('[login] recv',data.encode('hex'))
-        log('[login] packet sent.')
-        if address == (svr, 61440):
-            if data[0] == '\x04':
-                log('[login] loged in')
-                break
-            else:
-                log('[login] login failed.')
-                if IS_TEST:
-                    time.sleep(3)
-                else:
-                    time.sleep(30)
-                continue
-        else:
-            if i >= 5 and UNLIMITED_RETRY == False :
-                log('[login] exception occured.')
-                sys.exit(1)
-            else:
-                continue
-            
-    log('[login] login sent')
-    #0.8 changed:
-    return data[23:39]
-    #return data[-22:-6]
-
-def keep_alive1(salt,tail,pwd,svr):
-    foo = struct.pack('!H',int(time.time())%0xFFFF)
-    data = '\xff' + md5sum('\x03\x01'+salt+pwd) + '\x00\x00\x00'
-    data += tail
-    data += foo + '\x00\x00\x00\x00'
-    log('[keep_alive1] send',data.encode('hex'))
-
-    s.sendto(data, (svr, 61440))
+    packet = keep_alive_package_builder(i+1, cookie, 3, False)
+    socket.sendto(packet, (svr, 61440))
+    data, address = socket.recvfrom(1024)
+    cookie = data[16:20]
+
+    i = (i+2) % 0xFF
+    time.sleep(20)
+    keep_alive1(salt, old_cookie, pwd, svr, socket)
+
+
+def keep_alive1(salt, cookie, pwd, svr, socket):
+  log('DEBUG', 'keep_alive1()')
+  foo = struct.pack('!H',int(time.time())%0xFFFF)
+  data = '\xff' + md5sum('\x03\x01'+salt+pwd) + '\x00\x00\x00'
+  data += cookie
+  data += foo + '\x00\x00\x00\x00'
+  log('DEBUG', 'send:'+data.encode('hex'))
+  socket.sendto(data, (svr, 61440))
+  while True:
+    data, address = socket.recvfrom(1024)
+    log('DEBUG', 'recv:'+data.encode('hex'))
+    if data[0] == '\x07':
+      break
+    else:
+      log('WARN', 'unexpected recv:'+data.encode('hex'))
+
+
+def keep_alive_pre_1(svr_num, cookie, svr, socket):
+  log('DEBUG', 'keep_alive_pre_1()')
+  packet = keep_alive_package_builder(svr_num, '\x00'*4, 1, True)
+  log('DEBUG', 'send:'+packet.encode('hex'))
+  while True:
+    socket.sendto(packet, (svr, 61440))
+    data, address = socket.recvfrom(1024)
+    log('DEBUG', 'recv:'+data.encode('hex'))
+    if data.startswith('\x07\x00\x28\x00') or data.startswith('\x07' + chr(svr_num)  + '\x28\x00'):
+      break
+    # 2014/10/15 add by latyas, maybe svr sends back a file packet
+    elif data[0] == '\x07' and data[2] == '\x10':
+      svr_num = svr_num + 1
+      packet = keep_alive_package_builder(svr_num, '\x00'*4, 1, False)
+    else:
+      log('WARN', 'unexpected recv:'+data.encode('hex'))
+  return svr_num, None
+
+def keep_alive_pre_2(svr_num, cookie, svr, socket):
+  log('DEBUG', 'keep_alive_pre_2()')
+  packet = keep_alive_package_builder(svr_num, '\x00'*4, 1, False)
+  log('DEBUG', 'send:'+packet.encode('hex'))
+  socket.sendto(packet, (svr, 61440))
+  while True:
+    data, address = socket.recvfrom(1024)
+    log('DEBUG', 'recv:'+data.encode('hex'))
+    if data[0] == '\x07':
+      svr_num = svr_num + 1
+      break
+    else:
+      log('WARN', 'unexpected recv:'+data.encode('hex'))
+  cookie = data[16:20]
+  return svr_num, cookie
+
+def keep_alive_pre_3(svr_num, cookie, svr, socket):
+  log('DEBUG', 'keep_alive_pre_3')
+  packet = keep_alive_package_builder(svr_num, cookie, 3, False)
+  log('DEBUG', 'send:'+packet.encode('hex'))
+  socket.sendto(packet, (svr, 61440))
+  while True:
+    data, address = socket.recvfrom(1024)
+    log('DEBUG', 'recv:'+data.encode('hex'))
+    if data[0] == '\x07':
+      svr_num = svr_num + 1
+      break
+    else:
+      log('WARN', 'unexpected recv:'+data.encode('hex'))
+  cookie = data[16:20]
+  return svr_num, cookie
+
+
+def keep_alive_package_builder(svr_number, cookie, type=1, first=False):
+  log('DEBUG', 'keep_alive_package_builder()')
+  data = '\x07'+ chr(svr_number) + '\x28\x00\x0b' + chr(type)
+  if first :
+    data += '\x0f\x27'
+  else:
+    data += KEEP_ALIVE_VERSION
+  data += '\x2f\x12' + '\x00' * 6
+  data += cookie
+  data += '\x00' * 4
+  if type == 3:
+    foo = ''.join([chr(int(i)) for i in host_ip.split('.')]) # host_ip
+    crc = '\x00' * 4
+    data += crc + foo + '\x00' * 8
+  else: #packet type = 1
+    data += '\x00' * 16
+  return data
+
+
+def empty_socket_buffer(socket):
+  #empty buffer for some fucking schools
+  log('DEBUG', 'starting to empty socket buffer')
+  try:
     while True:
-        data, address = s.recvfrom(1024)
-        if data[0] == '\x07':
-            break
-        else:
-            log('[keep-alive1]recv/not expected',data.encode('hex'))
-    log('[keep-alive1] recv',data.encode('hex'))
-
-def empty_socket_buffer():
-#empty buffer for some fucking schools
-    log('starting to empty socket buffer')
-    try:
-        while True:
-            data, address = s.recvfrom(1024)
-            log('recived sth unexpected',data.encode('hex'))
-            if s == '':
-                break
-    except:
-        # get exception means it has done.
-        log('exception in empty_socket_buffer')
-        pass
-    log('emptyed')
-def daemon():
-    with open('/var/run/jludrcom.pid','w') as f:
-        f.write(str(os.getpid()))
-        
+      data, address = socket.recvfrom(1024)
+      log('DEBUG', 'recived sth unexpected'+data.encode('hex'))
+      if socket == '':
+        break
+  except:
+    # get exception means it has done.
+    log('DEBUG', 'exception in empty_socket_buffer')
+  log('DEBUG', 'emptyed')
+
+
+def log(level, msg):
+  log_msg = '[%s]: %s (%s)' % (level, msg, datetime.datetime.now() )
+  if IS_DEBUG:
+    print log_msg
+    return 
+  if level == 'DEBUG':
+    return
+  try:
+    with open(LOG_PATH, 'a') as f:
+      f.write(log_msg+'\n')
+  except Exception as e:
+    print "Unable to log, %s" % e
+
 def main():
-    if not IS_TEST:
-        daemon()
-        execfile(CONF, globals())
-    log("auth svr:"+server+"\nusername:"+username+"\npassword:"+password+"\nmac:"+str(hex(mac)))
-    log(bind_ip)
-    while True:
-      try:
-        package_tail = login(username, password, server)
-      except LoginException:
-        continue
-      log('package_tail',package_tail.encode('hex'))
-      #keep_alive1 is fucking bullshit!
-      empty_socket_buffer()
-      keep_alive1(SALT,package_tail,password,server)
-      keep_alive2(SALT,package_tail,password,server)
+  os.environ["TZ"] = 'Asia/Shanghai'
+  time.tzset()
+  log('INFO', 'starting...')
+  is_first_time = True
+  while RETRY or is_first_time:
+    is_first_time = False
+    try:
+      socket = setup_socket(bind_ip)
+      salt = get_salt(socket, server, random.randint(0xF,0xFF))
+      cookie = do_login(username, password, salt, mac, server, socket)
+      empty_socket_buffer(socket)
+      keep_alive(password, salt, cookie, server, socket)
+    except LoginException as e:
+      pass
+    except Exception as e: #normal exception is timeout, which mostly caused by multiplace login and this session is ticked out
+      log('WARN', e)
+      socket.close()
+      log('INFO', 'release socket')
+    time.sleep(15)
+  log('INFO', 'process quit')
+
 if __name__ == "__main__":
-    main()
+  main()