python如何判断网络是否通

python如何判断网络是否通

目录

判断网络是否通

检测网络连接状态的几种方式

判断网络是否通

提供两种方法:

netstats.py

# -*- coding: gbk -*- import myarp import os class netStatus:     def internet_on(self,ip="192.168.150.1"):         os.system("arp -d 192.168.150.1")         if myarp.arp_resolve(ip, 0) == 0:   #使用ARP ping的方法             return True         else:             return False     def ping_netCheck(self, ip):           #直接ping的方法         os.system("arp -d 192.168.150.1")         cmd = "ping " +str(ip) + " -n 2"         exit_code = os.system(cmd)         if exit_code:             return False         return True if __name__ == "__main__":     net = netStatus()     print net.ping_netCheck("192.168.150.2")

myarp.py(这个是从ARP模块改来的) 

""" ARP / RARP module (version 1.0 rev 9/24/2011) for Python 2.7 Copyright (c) 2011 Andreas Urbanski. Contact the me via e-mail: urbanski.andreas@gmail.com This module is a collection of functions to send out ARP (or RARP) queries and replies, resolve physical addresses associated with specific ips and to convert mac and ip addresses to different representation formats. It also allows you to send out raw ethernet frames of your preferred protocol type. DESIGNED FOR USE ON WINDOWS. NOTE: Some functions in this module use winpcap for windows. Please make sure that wpcap.dll is present in your system to use them. LICENSING: This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/> """ __all__ = ['showhelp', 'find_device', 'open_device', 'close_device', 'send_raw', 'multisend_raw', 'arp_resolve', 'arp_reply', 'rarp_reply', 'mac_straddr', 'ip_straddr', 'ARP_REQUEST', 'ARP_REPLY', 'RARP_REQUEST', 'RARP_REPLY', 'FRAME_SAMPLE'] """ Set this to True you wish to see warning messages """ __warnings__ = False from ctypes import * import socket import struct import time FRAME_SAMPLE = """ Sample ARP frame +-----------------+------------------------+ | Destination MAC | Source MAC | +-----------------+------------------------+ | \\x08\\x06 (arp) | \\x00\\x01 (ethernet) | +-----------------+------------------------+ | \\x08\\x00 (internet protocol) | +------------------------------------------+ | \\x06\\x04 (hardware size & protocol size) | +------------------------------------------+ | \\x00\\x02 (type: arp reply) | +------------+-----------+-----------------+ | Source MAC | Source IP | Destination MAC | +------------+---+-------+-----------------+ | Destination IP | ... Frame Length: 42 ... +----------------+ """ """ Frame header bytes """ ARP_REQUEST = "\x08\x06\x00\x01\x08\x00\x06\x04\x00\x01" ARP_REPLY = "\x08\x06\x00\x01\x08\x00\x06\x04\x00\x02" RARP_REQUEST = "\x80\x35\x00\x01\x08\x00\x06\x04\x00\x03" RARP_REPLY = "\x80\x35\x00\x01\x08\x00\x06\x04\x00\x04" """ Defines """ ARP_LENGTH = 42 RARP_LENGTH = 42 DEFAULT = 0 """ Look for wpcap.dll """ try: wpcap = cdll.wpcap except WindowsError: print "Error loading wpcap.dll! Ensure that winpcap is properly installed." """ Loading Windows system libraries should not be a problem """ try: iphlpapi = windll.Iphlpapi ws2_32 = windll.ws2_32 except WindowsError: """ Should it still fail """ print "Error loading windows system libraries!" """ Import functions """ if wpcap: """ Looks up for devices """ pcap_lookupdev = wpcap.pcap_lookupdev """ Opens a device instance """ popen_live = wpcap.pcap_open_live """ Sends raw ethernet frames """ pcap_sendpacket = wpcap.pcap_sendpacket """ Close and cleanup """ pcap_close = wpcap.pcap_close """ Find the first device available for use. If this fails to retrieve the preferred network interface identifier, disable all other interfaces and it should work.""" def find_device(): errbuf = create_string_buffer(256) device = c_void_p device = pcap_lookupdev(errbuf) return device """ Get the handle to a network device. """ def open_device(device=DEFAULT): errbuf = create_string_buffer(256) if device == DEFAULT: device = find_device() """ Get a handle to the ethernet device """ eth = popen_live(device, 4096, 1, 1000, errbuf) return eth """ Close the device handle """ def close_device(device): pcap_close(device) """ Send a raw ethernet frame """ def send_raw(device, packet): if not pcap_sendpacket(device, packet, len(packet)): return len(packet) """ Send a list of packets at the specified interval """ def multisend_raw(device, packets=[], interval=0): """ Bytes sent """ sent = 0 for p in packets: sent += len(p) send_raw(device, p) time.sleep(interval) """ Return the number of bytes sent""" return sent """ Resolve the mac address associated with the destination ip address""" def arp_resolve(destination, strformat=True, source=None): mac_addr = (c_ulong * 2)() addr_len = c_ulong(6) dest_ip = ws2_32.inet_addr(destination) if not source: src_ip = ws2_32.inet_addr(socket.gethostbyname(socket.gethostname())) else: src_ip = ws2_32.inet_addr(source) """ Iphlpapi SendARP prototype DWORD SendARP( __in IPAddr DestIP, __in IPAddr SrcIP, __out PULONG pMacAddr, __inout PULONG PhyAddrLen ); """ error = iphlpapi.SendARP(dest_ip, src_ip, byref(mac_addr), byref(addr_len)) return error """ Send a (gratuitous) ARP reply """ def arp_reply(dest_ip, dest_mac, src_ip, src_mac): """ Test input formats """ if dest_ip.find('.') != -1: dest_ip = ip_straddr(dest_ip) if src_ip.find('.') != -1: src_ip = ip_straddr(src_ip) """ Craft the arp packet """ arp_packet = dest_mac + src_mac + ARP_REPLY + src_mac + src_ip + \ dest_mac + dest_ip if len(arp_packet) != ARP_LENGTH: return -1 return send_raw(open_device(), arp_packet) """ Include RARP for consistency :)""" def rarp_reply(dest_ip, dest_mac, src_ip, src_mac): """ Test input formats """ if dest_ip.find('.') != -1: dest_ip = ip_straddr(dest_ip) if src_ip.find('.') != -1: src_ip = ip_straddr(src_ip) """ Craft the rarp packet """ rarp_packet = dest_mac + src_mac + RARP_REPLY + src_mac + src_ip + \ src_mac + src_ip if len(rarp_packet) != RARP_LENGTH: return -1 return send_raw(open_device(), rarp_packet) """ Convert c_ulong*2 to a hexadecimal string or a printable ascii string delimited by the 3rd parameter""" def mac_straddr(mac, printable=False, delimiter=None): """ Expect a list of length 2 returned by arp_query """ if len(mac) != 2: return -1 if printable: if delimiter: m = "" for c in mac_straddr(mac): m += "%02x" % ord(c) + delimiter return m.rstrip(delimiter) return repr(mac_straddr(mac)).strip("\'") return struct.pack("L", mac[0]) + struct.pack("H", mac[1]) """ Convert address in an ip dotted decimal format to a hexadecimal string """ def ip_straddr(ip, printable=False): ip_l = ip.split(".") if len(ip_l) != 4: return -1 if printable: return repr(ip_straddr(ip)).strip("\'") return struct.pack( "BBBB", int(ip_l[0]), int(ip_l[1]), int(ip_l[2]), int(ip_l[3]) ) def showhelp(): helpmsg = """ARP MODULE HELP (Press ENTER for more or CTRL-C to break) Constants: Graphical representation of an ARP frame FRAME_SAMPLE Headers for crafting ARP / RARP packets ARP_REQUEST, ARP_REPLY, RARP_REQUEST, RARP_REPLY Other ARP_LENGTH, RARP_LENGTH, DEFAULT Functions: find_device() - Returns an identifier to the first available network interface. open_device(device=DEFAULT) - Returns a handle to an available network device. close_device() - Close the previously opened handle. send_raw(device, packet) - Send a raw ethernet frame. Returns the number of bytes sent. multisend_raw(device, packetlist=[], interval=0) - Send multiple packets across a network at the specified interval. Returns the number of bytes sent. arp_resolve(destination, strformat=True, source=None) - Returns the mac address associated with the ip specified by 'destination'. The destination ip is supplied in dotted decimal string format. strformat parameter specifies whether the return value is in a hexadecimal string format or in list format (c_ulong*2) which can further be formatted using the 'mac_straddr' function (see below). 'source' specifies the ip address of the sender, also supplied in dotted decimal string format. arp_reply(dest_ip, dest_mac, src_ip, src_mac) - Send gratuitous ARP replies. This can be used for ARP spoofing if the parameters are chosen correctly. dest_ip is the destination ip in either dotted decimal string format or hexadecimal string format (returned by 'ip_straddr'). dest_mac is the destination mac address and must be in hexadecimal string format. If 'arp_resolve' is used with strformat=True the return value can be used directly. src_ip specifies the ip address of the sender and src_mac the mac address of the sender. rarp_reply(dest_ip, dest_mac, src_ip, src_mac) - Send gratuitous RARP replies. Operates similar to 'arp_reply'. mac_straddr(mac, printable=False, delimiter=None) - Convert a mac address in list format (c_ulong*2) to normal hexadecimal string format or printable format. Alternatively a delimiter can be specified for printable formats, e.g ':' for ff:ff:ff:ff:ff:ff. ip_straddr(ip, printable=False) - Convert an ip address in dotted decimal string format to hexadecimal string format. Alternatively this function can output a printable representation of the hex string format. """ for line in helpmsg.split('\n'): print line, raw_input('') if __name__ == "__main__": """ Test the module by sending an ARP query """ ip = "10.0.0.8" result = arp_resolve(ip, 0) print ip, "is at", mac_straddr(result, 1, ":") 检测网络连接状态的几种方式

第一种

import socket ipaddress = socket.gethostbyname(socket.gethostname()) if ipaddress == '127.0.0.1':     return False else:     return True

缺点:如果IP是静态配置,无法使用,因为就算断网,返回的也是配置的静态IP

第二种

import urllib3 try:     http = urllib3.PoolManager()     http.request('GET', 'https://baidu.com')     return True except as e:     return False

第三种

import os ret = os.system("ping baidu.com -n 1") return True if res == 0 else False

第四种

import subprocess import os  ret = subprocess.run("ping baidu.com -n 1", shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE) return True if ret.returncode == 200 else False

以上为个人经验,希望能给大家一个参考,也希望大家多多支持易知道(ezd.cc)。

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