tcp端口扫描（python多线程）

1 使用单线程扫描单台主机

首先实现的是对单台主机中0-1024端口的扫描，发现差不多每秒扫描一个端口，很慢。

import socket

def tcp_scanner(host,port):
    client = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
    try:
        client.connect((host, port))
        print('connected to host %s,port %d successfully' %(host,port))
        return True
    except:
        # print('connected to host %s,port %d failed'  %(host,port))
        return False

if __name__ == '__main__':
    host = "192.168.10.10"
    for port in range(1024):
        tcp_scanner(host,port)

　　

2 使用多线程扫描单台主机

import threading,socket

def tcp_scanner(host,port):
    client = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
    try:
        client.connect((host, port))
        print('connected to host %s,port %d successfully' %(host,port))
        client.close()
        return True
    except:
        # print('connected to host %s,port %d failed'  %(host,port))
        return False

if __name__ == '__main__':
    host = "192.168.10.10"
    for port in range(1,1024):
        th = threading.Thread(target=tcp_scanner,args=(host,port))
        th.start()

　　

在运行以上代码时，出现报错：RuntimeError: can't start new thread，原因是超过了线程启动数的上限。

解决办法是修改最大文件描述符打开数。

3 使用多线程扫描多台主机

import threading,socket,subprocess

def tcp_scanner(host,port):
    client = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
    try:
        client.connect((host, port))
        print('connected to host %s,port %d successfully' %(host,port))
        client.close()
        return True
    except:
        # print('connected to host %s,port %d failed'  %(host,port))
        return False

def main():

    for i in range(2,255):

        # host = "10.224.32.%d" %i
        host = "192.168.136.%d" %i
        cmd = 'fping %s 1>/dev/null 2>&1;echo $?' %host
        p = subprocess.Popen(cmd,stdout=subprocess.PIPE,shell=True)
        ret = int(p.stdout.read())
        if ret == 0:
            for port in range(1,4000):
                th = threading.Thread(target=tcp_scanner,args=(host,port))
                th.start()
        else:
            print('status of %s:False' %host)

if __name__ == '__main__':
    main()

　　

上面的问题又出现了，可以用的文件描述符不够，即使改到655350。毕竟是全盘扫描。

解决办法是加信号threading.Semaphore，限制线程数

'''
create  2018/9/24
version 1.0
auth    jabbok
info    scan all the tcp port of the listed hosts by multithreading,to know is it listened
'''

import threading,socket,subprocess,time

screenLock = threading.Semaphore(value=1)

def tcp_scanner(host,port):

    socket.setdefaulttimeout(1)
    client = socket.socket(socket.AF_INET,socket.SOCK_STREAM)

    try:
        client.connect((host, port))
        print('connected to host %s,port %d successfully' %(host,port))
        client.close()
        screenLock.acquire()
        return True

    except:
        screenLock.acquire()
        return False

    finally:
        screenLock.release()
        client.close()

def main():

    for i in range(2,255):
        # host = "10.224.32.%d" %i
        host = "192.168.136.%d" %i
        cmd = 'fping %s 1>/dev/null 2>&1;echo $?' %host
        p = subprocess.Popen(cmd,stdout=subprocess.PIPE,shell=True)
        ret = int(p.stdout.read())

        if ret == 0:
            for port in range(1,4000):
                th = threading.Thread(target=tcp_scanner,args=(host,port))
                th.start()

        else:
            print('status of %s:False' %host)

if __name__ == '__main__':
    main()