ICMP Ping实现

第一关 Ping客户端创建原始套接字

#ICMPPing.py
 
import socket
import os
import struct
import time
import select
 
ICMP_ECHO_REQUEST = 8
 
#生成校验和
def checksum(str):
    csum = 0
    countTo = (len(str) / 2) * 2
    count = 0
    while count < countTo:
        thisVal = str[count + 1] * 256 + str[count]
        csum = csum + thisVal
        csum = csum & 0xffffffff
        count = count + 2
    if countTo < len(str):
        csum = csum + str[len(str) - 1].decode()
        csum = csum & 0xffffffff
    csum = (csum >> 16) + (csum & 0xffff)
    csum = csum + (csum >> 16)
    answer = ~csum
    answer = answer & 0xffff
    answer = answer >&