大概框架

多加判断和异常处理！！！**
解析主机

解析端口

端口扫描

定义主模块（帮助文档）

入口文件调用

  1. import socket,sys,re,threading,optparse
  2. def resolve_host(target_host):   #三种情况  1：IP地址、域名、都不是
  3.     try:
  4.         pattern = re.compile(r'\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}')
  5.         res = pattern.match(target_host)
  6.         if res:
  7.             return res.group()
  8.         else:
  9.             try:
  10.                 target_host = socket.gethostbyname(target_host)  #会报错，所以用try except
  11.                 exit(0)
  12.             except Exception as err:
  13.                 print("地址解析错误",err)
  14.     except Exception as err:
  15.         print(sys.exc_info()[0],err)   #sys.exc_info()[0]获取异常类型，err获取异常内容
  16.         exit(0)
  18. def resovle_port(target_port):   #三种情况 1：start_port-end_port 2：xxx,xxx,xxx 3：都不是(不用加try except，因为for循环会自动检测)
  19.     try:
  20.         pattern = re.compile(r'(\d+)-(\d+)')
  21.         res = pattern.match(target_port)
  22.         if res:
  23.             start_port =  int(res.group(1))
  24.             end_port =  int(res.group(2))
  25.             return [x for x in range(start_port,end_port+1)]   #end_port+1是因为要包含end_port，range默认不包含最后一个值
  26.         else:
  27.             return [x for x in target_port.split(',')]
  28.     except Exception as err:
  29.         print(sys.exc_info()[0],err)
  30.         exit(0)
  32. def scan(target_host,target_port):   #创建对象，设置超时时间，做try、except
  33.     scan = socket.socket()
  34.     scan.settimeout(5)
  35.     try:
  36.         scan.connect((target_host,target_port))  #传入的参数为元组形式
  37.         print('[+]%s的%3s端口:open' % (target_host,target_port))  #%3s填充字符串，留3个位置，不够空格填充
  38.         scan.close()
  39.     except socket.timeout:
  40.         print("[-]%s的%3s端口:close" % (target_host,target_port))
  41.     except Exception as err:
  42.         #print(sys.exc_info()[0],err)
  43.         exit(0)
  45. def main():
  46.     usage = 'python3 %prog --host <host> --port <port>'
  47.     parser = optparse.OptionParser(usage,version="%prog v1.0")
  48.     parser.add_option('--host',dest='target_host',type=str,help='目标主机地址，IP或域名')
  49.     parser.add_option('--port',dest='target_port',type=str,help='目标主机端口，x-x或x,x,x')
  50.     (options,args) = parser.parse_args()
  52.     if options.target_host == None or options.target_port == None:
  53.         print(parser.usage)
  54.         exit(0)
  55.     else:
  56.         target_host = resolve_host(options.target_host)
  57.         target_port = resovle_port(options.target_port)
  59.     for port in target_port:
  60.         # 传入的参数为元组形式 | 一个参数后面加逗号！！
  61.         t = threading.Thread(target=scan,args=(target_host,port)).start()
  63. if __name__ == '__main__':
  64.     main()