python 实现端口扫描工具

# 简单的端口扫描工具
# 作者: Charles
# 公众号: Charles的皮卡丘
import time
import socket
import threading

# 判断是否为正确的IP地址。
def isIP(ip):
  ip_addr = ip.split('.')
  if len(ip_addr) != 4:
   return False
  for ipnum in ip_addr:
   if not (0 <= int(ipnum) < 255):
     return False
  else:
   return True


# 端口扫描工具
class scanThread(threading.Thread):
  def __init__(self, ip, port_min=0, port_max=65535):
   # 初始化。
   threading.Thread.__init__(self)
   self.port_max = port_max
   self.port_min = port_min
   self.ip = ip
   # assert isinstance(int,self.port_min) and isinstance(int,self.port_max)
  # 重写run
  def run(self):
   return self.__checker()
  # 检测
  def __checker(self):
   
   for port in range(self.port_min,self.port_max):
     self.__connect(port)
  # 连接
  def __connect(self,port):
   socket.setdefaulttimeout(1)
   self.sock = socket.socket()
   try:
     start_time = time.time()
     self.sock.connect((self.ip,port))
     end_time = time.time()
     connect_time = int(start_time - end_time)
     info = 'Find --> [IP]: %s, [PORT]: %s, [Connect Time]: %d' % (self.ip, port, connect_time)
     print(info)
     self.__save(info)
     self.sock.close()
   except:
     # print('出错误了')
     self.sock.close()
  def __save(self,info):
   try:
     with open('results.txt', 'a') as f:
      f.write(info + '\n')
   except:
     print('写文件出现了问题')
     time.sleep(0.1)

if __name__ == '__main__':
  # 输入IP地址。
  ip = input('Input IP(example <xxx.xxx.xxx.xxx>):\n')
  print(isIP(ip))
  while not isIP(ip):
   ip = input('请输入正确的IP地址:\n')
  # 输入最小端口、
  port_min = input('需要扫描的最小端口为：')
  while not (0 <= int(port_min) < 65535):
   port_min = input('请输入正确的需要扫描的最小端口：')
  port_max = input('需要扫描的最大端口为（65535）：')
  while not (0 <= int(port_min) < int(port_max) < 65535):
   port_min = input('请输入正确的需要扫描的最大端口（65535）：')
  num = 8
  port_max = int(port_max)
  port_min = int(port_min)
  interval = (port_max - port_min) // num
  for i in range(interval):
   scanThread(ip, i * num, (i + 1) * num).start()