Python:如何检查网络端口是否在Linux上打开？

Question

我如何知道某个端口是否在linux ubuntu上打开/关闭,而不是远程系统,使用python？如何在python中列出这些开放端口？

• Netstat:有没有办法将netstat输出与python集成？

Answer 1

您可以使用套接字模块来检查端口是否打开.

它看起来像这样.

import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
result = sock.connect_ex(('127.0.0.1',80))
if result == 0:
   print "Port is open"
else:
   print "Port is not open"
sock.close()

Answer 2

如果要在更一般的上下文中使用它,则应确保打开的套接字也已关闭.所以检查应该更像这样:

import socket
from contextlib import closing

def check_socket(host, port):
    with closing(socket.socket(socket.AF_INET, socket.SOCK_STREAM)) as sock:
        if sock.connect_ex((host, port)) == 0:
            print "Port is open"
        else:
            print "Port is not open"

Answer 3

对我来说,如果端口未打开,上面的示例将会挂起.第4行显示了使用settimeout来防止挂起

import socket

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.settimeout(2)                                      #2 Second Timeout
result = sock.connect_ex(('127.0.0.1',80))
if result == 0:
  print 'port OPEN'
else:
  print 'port CLOSED, connect_ex returned: '+str(result)

Answer 4

如果您只关心本地计算机,则可以依赖psutil包.你可以:

1. 检查特定pid使用的所有端口:

   proc = psutil.Process(pid)
   print proc.connections()
   

2. 检查本地计算机上使用的所有端口:

   print psutil.net_connections()
   

它也适用于Windows.

http://pythonhosted.org/psutil/

Answer 5

我在这篇文章中找到了多种解决方案。但某些解决方案存在挂起问题或在端口未打开的情况下花费太多时间。请尝试以下解决方案：

import socket 

def port_check(HOST):
   s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
   s.settimeout(2) #Timeout in case of port not open
   try:
      s.connect((HOST, 22)) #Port ,Here 22 is port 
      return True
   except:
      return False

port_check("127.0.1.1")

Answer 6

这是一个快速的多线程端口扫描器：

from time import sleep
import socket, ipaddress, threading

max_threads = 50
final = {}
def check_port(ip, port):
    try:
        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) # TCP
        #sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) # UDP
        socket.setdefaulttimeout(2.0) # seconds (float)
        result = sock.connect_ex((ip,port))
        if result == 0:
            # print ("Port is open")
            final[ip] = "OPEN"
        else:
            # print ("Port is closed/filtered")
            final[ip] = "CLOSED"
        sock.close()
    except:
        final[ip] = "EXCEPTION"
        
port = 22
for ip in ipaddress.IPv4Network('95.217.210.0/24'): 
    threading.Thread(target=check_port, args=[str(ip), port]).start()
    #sleep(0.1)

    # limit the number of threads.
    while threading.active_count() > max_threads :
        sleep(1)


sorted_ips = dict(sorted(final.items(), key=lambda item: tuple(map(int, item[0].split('.')))))

for ip, state in sorted_ips.items():
    print(ip, state)

现场演示

Answer 7

刚刚在 mrjandro 的解决方案中添加了一些改进，例如自动资源管理（确保打开的套接字也被关闭）、处理超时、消除简单的连接错误/超时以及打印结果：

import socket
from contextlib import closing

hosts = ["host1", "host2", "host3"]
port = 22
timeout_in_seconds = 2

hosts_with_opened_port = []
hosts_with_closed_port = []
hosts_with_errors = []


def check_port(host, port, timeout_in_seconds):
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.settimeout(timeout_in_seconds)
    with closing(socket.socket(socket.AF_INET, socket.SOCK_STREAM)) as sock:
        try:
            result = sock.connect_ex((host, port))
            if result == 0:
                print("Port {} is *** OPEN *** on host: {}".format(port, host))
                hosts_with_opened_port.append(host)
            else:
                print("Port {} is not open on host: {}".format(port, host))
                hosts_with_closed_port.append(host)
        except socket.gaierror:
            print("Port {} check returns a network *** ERROR *** on host: {}".format(port, host))
            hosts_with_errors.append(host)


for host in hosts:
    check_port(host, port, timeout_in_seconds)

print("\nHosts with opened port:")
print(hosts_with_opened_port)
print("\nHosts with closed port:")
print(hosts_with_closed_port)
print("\nHosts with errors:")
print(hosts_with_errors)

Answer 8

如果您探测 TCP 端口并打算侦听它，最好实际调用侦听。使用 tring 连接的方法是 don\xe2\x80\x99t“查看”已建立连接的客户端端口，因为没有人监听它。但这些端口不能用于监听它。

\n\n

import socket\n\n\ndef check_port(port, rais=True):\n    """ True -- it\'s possible to listen on this port for TCP/IPv4 or TCP/IPv6\n    connections. False -- otherwise.\n    """\n    try:\n        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)\n        sock.bind((\'127.0.0.1\', port))\n        sock.listen(5)\n        sock.close()\n        sock = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)\n        sock.bind((\'::1\', port))\n        sock.listen(5)\n        sock.close()\n    except socket.error as e:\n        return False\n        if rais:\n            raise RuntimeError(\n                "The server is already running on port {0}".format(port))\n    return True\n

\n

Answer 9

基于psutilJoe 提到的解决方案（仅适用于检查本地端口）：

import psutil
1111 in [i.laddr.port for i in psutil.net_connections()]

True如果当前使用端口 1111，则返回。

psutil不是 python stdlib 的一部分，所以你需要pip install psutil首先。它还需要 python 标头可用，因此您需要类似的东西python-devel