私人笔记----竹叶青青

ICMP

1.windows python ———ICMP

import socket
import struct
def checksum(source_string):
    sum = 0
    countTo = (len(source_string)/2)*2
    count = 0
    while count<countTo:
        thisVal = ord(source_string[count + 1:count + 2])*256 + ord(source_string[count:count + 1])
        sum = sum + thisVal
        sum = sum & 0xffffffff 
        count = count + 2
    if countTo<len(source_string):
        sum = sum + ord(source_string[len(source_string) - 1])
        sum = sum & 0xffffffff 
    sum = (sum >> 16)  +  (sum & 0xffff)
    sum = sum + (sum >> 16)
    answer = ~sum
    answer = answer & 0xffff
    answer = answer >> 8 | (answer << 8 & 0xff00)
    return answer
def ping(ip):
    rawsocket1=socket.socket(socket.AF_INET,socket.SOCK_RAW,socket.getprotobyname("icmp"))
    packet = struct.pack('!BBHHH8s', 8, 0, 0, 0, 0, b'abcdefgh')
    chksum=checksum(packet)
    packet = struct.pack('!BBHHH8s', 8, 0, chksum, 0, 0, b'abcdefgh')
    rawsocket1.sendto(packet, (ip, 11111))
    data,addr = rawsocket1.recvfrom(1204)
    print type(data),addr,"\n",data
    by=""
    for k in range(1,17):
        by+=data[-(17-k)]
    print by
    pcket=struct.unpack('!BBHHH8s',by)
    print pcket

ping('xx.xx.xx.xx')

因为收到的包不仅仅包括ICMP Reply包的16个字节，所以先取出后面的16个

struct

2.关于struct
struct.pack(‘格式’,变量1,变量2…)
对应C语言的格式

注: unsigned char —-BYTE unsigned short—-USHORT