python监听数据变化(python监听数据包)

Python是一种高级编程语言，常常用于网络编程。本文将介绍如何使用Python监听数据包。

# 导入所需模块
import socket
import struct
# 定义IP头格式
ip_header = struct.Struct('!BBHHHBBH4s4s')
def parse_ip_header(data):
"""解析IP头"""
version_header_length, tos, total_length, id_, flags_offset, ttl, protocol, checksum, source_address, dest_address = ip_header.unpack(data[:20])
version = version_header_length >>4
header_length = (version_header_length & 0xF) * 4
return version, header_length, ttl, protocol, source_address, dest_address, data[header_length:total_length]
# 定义TCP头格式
tcp_header = struct.Struct('!HHLLBBHHH')
def parse_tcp_header(data):
"""解析TCP头"""
source_port, dest_port, seq_num, ack_num, offset_reserved_flags, window_size, checksum, urgent_pointer = tcp_header.unpack(data[:20])
offset = (offset_reserved_flags >>4) * 4
flags = offset_reserved_flags & 0xF
return source_port, dest_port, seq_num, ack_num, flags, window_size, data[offset:]
# 创建套接字并监听
HOST = '127.0.0.1'
PORT = 8888
with socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_TCP) as s:
s.bind((HOST, PORT))
s.setsockopt(socket.IPPROTO_IP, socket.IP_HDRINCL, 1)
s.ioctl(socket.SIO_RCVALL, socket.RCVALL_ON)
while True:
data, addr = s.recvfrom(65535)
version, header_length, ttl, protocol, source_address, dest_address, payload = parse_ip_header(data)
if protocol == socket.IPPROTO_TCP:
source_port, dest_port, seq_num, ack_num, flags, window_size, tcp_payload = parse_tcp_header(payload)
print(f'source_address: {source_address}, source_port: {source_port}, dest_address: {dest_address}, dest_port: {dest_port}, flags: {flags}, tcp_payload: {tcp_payload}')

以上代码通过创建原始套接字，并监听TCP数据包，解析IP头和TCP头，输出相关信息。