一个用python写的简单的端口扫描器，python环境为 3.7.0，windows系统

扫描给定主机是否开放了指定的端口
TCP连接扫描是利用TCP的三次握手来确定主机的端口是否开放。确定主机端口开放之后，给端口发送消息，接收端口返回的消息，然后判断该端口运行的服务。
使用时，-H 参数可以提供主机的域名或者ip地址，-p/-P 写要扫描的端口，多个端口用逗号分隔

'''@Author:yw参考书籍:《python绝技：运用python成为顶级***》'''import optparsefrom socket import *import threadingthreadlock = threading.Lock() #实例化threadlock对象def Conn_scan(Host, Port): try: conn = socket(AF_INET,SOCK_STREAM) conn.connect((Host, Port)) #conn.send('ywboy'.encode('utf-8')) #发送测试 #results = conn.recv(100) #接收主机返回的信息 threadlock.acquire() #加锁 print("[+]%d/tcp Open" % Port) #print('[+]'+results.decode('utf-8')) conn.close() except Exception as e: threadlock.acquire() #释放锁 print('[-]%d/Tcp Closed' % Port) finally: threadlock.release() conn.close()def Port_scan(Host, Ports): try: IP = gethostbyname(Host) ##获得对应主机的ip地址 except: print("[-] Cannot resolve '%s':Unknow host" % Host) return try: Name = gethostbyaddr(Host) ##获得对应主机的信息,返回主机名、主机别名列表、主机IP地址列表 print("\n[+] Scan result for:"+Name[0]) except: print("\n[+] Scan Results for:"+IP) setdefaulttimeout(1) for Port in Ports: print("Scan port:"+Port) Conn_scan(Host, int(Port))def main(): usage = "usage %prog -H <target Host> -p/-P <target ports>" parse = optparse.OptionParser(usage) parse.add_option('-H', dest='Host', type='string', help='target Host') parse.add_option('-p','-P', dest='Ports', type='string', help='SCan Port') (options, args) = parse.parse_args() Host = options.Host Ports = str(options.Ports).split(',') if (Host==None)|(Ports==None): print(parse.usage) exit(0) Port_scan(Host,Ports)if __name__ == '__main__': main()

上述代码，因为我只是做了端口扫描，所以注释掉的判断端口扫描服务的代码

运行结果：