模拟ssh, hashlib模块, struct模块, subprocess模块

一. 模拟ssh

# ===================================== 服务器端 =====================================import socket
import subprocess    # 系统操作server = socket.socket()server.bind(('127.0.0.1',8008))server.listen(5)while True:print("server is working.....")conn,addr = server.accept()# 字节类型while True:# 针对window系统try:cmd = conn.recv(1024).decode("utf8") # 阻塞if cmd == b'exit':breakres=subprocess.Popen(cmd,shell=True,stderr=subprocess.PIPE,stdout=subprocess.PIPE,)# print("stdout",res.stdout.read())# print("stderr",res.stderr.read().decode("gbk"))out=res.stdout.read()err=res.stderr.read()print("out响应长度",len(out))print("err响应长度",len(err))if err:import structheader_pack = struct.pack("i", len(err))conn.send(header_pack)conn.send(err)else:#构建报头import structheader_pack=struct.pack("i",len(out))print("header_pack",header_pack)# # 发送报头conn.send(str(len(out)).encode("utf8"))# 发送数据conn.send(out)except Exception as e:breakconn.close()# ===================================== 客户端 =====================================
import socket
import structsk = socket.socket()sk.connect(('127.0.0.1', 8008))while 1:cmd = input("请输入命令：")sk.send(cmd.encode('utf-8'))  # 字节if cmd == "":  # 空字符串无法发送continueif cmd == 'exit':breakheader_pack = sk.recv(4)data_length = struct.unpack("i", header_pack)[0]  # unpack是一个元组print("data_length", data_length)data_length = int(sk.recv(1024).decode("utf8"))print("data_length", data_length)recv_data_length = 0recv_data = b""while recv_data_length < data_length:data = sk.recv(1024)recv_data_length += len(data)recv_data += dataprint(recv_data.decode("gbk"))sk.close()

　　

二. hashlib模块

import hashlibmd5=hashlib.md5()
md5.update(b"hello")
md5.update(b"yuan")print(md5.hexdigest())
print(len(md5.hexdigest()))#helloyuan:   d843cc930aa76f7799bba1780f578439
#             d843cc930aa76f7799bba1780f578439       # 多次update和单次update结果一样#############################################md5=hashlib.md5()with open("ssh_client.py","rb") as f:for line in f:md5.update(line)     # 多次update和单次update结果一样print(md5.hexdigest()) # f.read()

　　

三. struct模块

import structres=struct.pack("i",2934781)print(res)
print(len(res))obj=struct.unpack("i",res)
print(obj[0])

　　

四. subprocess模块 # windows系统明命令

import subprocessres=subprocess.Popen("dir",shell=True,stderr=subprocess.PIPE,stdout=subprocess.PIPE)print(res.stdout.read().decode("gbk"))