python 通过 http、dns、icmp判断网络状态

#http使用requests发包bs4解析，dns、icmp 使用scapy发包
import time
import threading
import requests,bs4
from scapy.all import *
from requests.exceptions import ReadTimeout,ConnectTimeout,HTTPError,ConnectionError
import struct

def send_http_packet(url):
    requests.packages.urllib3.disable_warnings()
    user_agent = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.86 Safari/537.36"
    headers = {'User-Agent': user_agent}
    url = "http://" + url
    response_html= ""
    try:
        response = requests.get(url, headers)
        response_html = response.content.decode()
        return response_html
    except ReadTimeout:
        print('Read Timeout')
        return None
    except ConnectTimeout:
        print('Connect Timeout')
        return None
    except HTTPError:
        print('HTTP Error')
        return None
    except ConnectionError:
        print('Connection Error')
        return None

def check_http(html,title):
    if html != None  and title != None :
        soup = bs4.BeautifulSoup(html, 'lxml')
        html_title = ""
        html_title = soup.title.text
        if title in html_title:
            return True
        else:
            return None
    else:
        print('html or title is None')
        return None

def shend_icmp_packet(ip_address):
    request_time = time.time()
    request_time = struct.pack('>d',request_time)
    response_packet = sr1(IP(dst=ip_address)/ICMP()/request_time,timeout=1,verbose = False)
    return response_packet

def icmp_relay_time(ip_address):
    response_packet = shend_icmp_packet(ip_address)
    relay_time = time.time()
    if response_packet != None :
        response_time = response_packet.getlayer(Raw).load
        response_time = struct.unpack('>d',response_time)
        relay_time = (relay_time - response_time[0])*1000
        return relay_time
    else:
        return None

def real_icmp_relay_time(gateway,ip_address):
    time_ipadd = icmp_relay_time(ip_address)
    time_gateway = icmp_relay_time(gateway)
    if time_ipadd == None or time_gateway == None:
        return None
    else:
        return time_ipadd - time_gateway

def send_dns_packet(domainname,dnsserver):
    i = IP(dst=dnsserver)
    u = UDP(dport = 53)
    d = DNS(rd=1)
    d.qd = DNSQR(qname = domainname , qtype = 1 ,qclass = 1)
    dns_request_packet = i/u/d
    dns_response_packet = sr1(dns_request_packet,timeout=2,verbose = False)
    if dns_response_packet != None:
        dns_response_packet = dns_response_packet.getlayer(DNS).fields
        if dns_response_packet['rcode'] == 0 :
            return dns_response_packet
        elif dns_response_packet['rcode'] == 3 :
            print("Domain Name Error")
            return None
        elif dns_response_packet['rcode'] == 2 :
            print("Server Inside Failure")
            return None
    else:
        print("dns server no response")
        return None

def main():

    # res = send_http_packet("www.baidu.com")
    # print(check_http(res,"百度"))

    res = real_icmp_relay_time("172.17.1.1","192.168.101.2")
    print(res)

    # res = send_dns_packet("www.baidu.com","114.114.114.144")
    # print(res)

if __name__ == '__main__':
    main()