socket通信中校验客户端的合法性

hmac模块 —— 推荐

# client
from socket import *
import hmac,os

secret_key=b'linhaifeng bang bang bang'
def conn_auth(conn):
    '''
    验证客户端到服务器的链接
    :param conn:
    :return:
    '''
    msg=conn.recv(32)
    h=hmac.new(secret_key,msg)
    digest=h.digest()
    conn.sendall(digest)

def client_handler(ip_port,bufsize=1024):
    tcp_socket_client=socket(AF_INET,SOCK_STREAM)
    tcp_socket_client.connect(ip_port)

    conn_auth(tcp_socket_client)

    while True:
        data=input('>>: ').strip()
        if not data:continue
        if data == 'quit':break

        tcp_socket_client.sendall(data.encode('utf-8'))
        respone=tcp_socket_client.recv(bufsize)
        print(respone.decode('utf-8'))
    tcp_socket_client.close()

if __name__ == '__main__':
    ip_port=('127.0.0.1',9999)
    bufsize=1024
    client_handler(ip_port,bufsize)


# server
# -*- coding:utf-8 -*-
from socket import *
import hmac,os

secret_key=b'linhaifeng bang bang bang'

def conn_auth(conn):
    '''
    认证客户端链接
    :param conn:
    :return:
    '''
    print('开始验证新链接的合法性')
    # 返回一个bytes类型的32字节的随机串
    msg_bytes=os.urandom(32)
    # 发给客户端
    conn.sendall(msg_bytes)
    # hmac.new方法
    h=hmac.new(secret_key,msg_bytes)
    digest=h.digest()
    respone=conn.recv(len(digest))
    return hmac.compare_digest(respone,digest)

def data_handler(conn,bufsize=1024):
    if not conn_auth(conn):
        print('该链接不合法,关闭')
        conn.close()
        return
    print('链接合法,开始通信')
    while True:
        data=conn.recv(bufsize)
        if not data:break
        conn.sendall(data.upper())

def server_handler(ip_port,bufsize,backlog=5):
    '''
    只处理链接
    :param ip_port:
    :return:
    '''
    tcp_socket_server=socket(AF_INET,SOCK_STREAM)
    tcp_socket_server.bind(ip_port)
    tcp_socket_server.listen(backlog)
    while True:
        conn,addr=tcp_socket_server.accept()
        print('新连接[%s:%s]' %(addr[0],addr[1]))
        data_handler(conn,bufsize)

if __name__ == '__main__':
    ip_port=('127.0.0.1',9999)
    bufsize=1024
    server_handler(ip_port,bufsize)

hashlib方法

# client
import socket
import hashlib

secret_key = b'wanghw'

client = socket.socket()
client.connect(('127.0.0.1'))

# 生成的是固定的32位字节
random_bytes = client.recv(32)


md5 = hashlib.md5(secret_key)
md5.update(random_bytes)
res = md5.hexdigest()

client.send(res.encode('utf-8'))

client.close()


# server
# -*- coding:utf-8 -*-
import os
import socket
import hashlib


## 随机的字节
## 给每一个客户端发一个随机的字符串，来保证即使数据被拦截了，也不能使用这个消息
random_bytes = os.urandom(32)
## 秘钥
secret_key = b'wanghw'

server = socket.socket()
server.bind(('127.0.0.1',9001))
server.listen()

conn,addr = server.accept()
conn.send(random_bytes)

md5 = hashlib.md5(secret_key)
md5.update(random_bytes)
res = md5.hexdigest()

# MD5位32位
# sha1位40位
ret = conn.recv(1024).decode('utf-8')

if ret == res:
    print('是合法的客户端')
    print('do sth')
else:
    print('不合法！')
    conn.close()