使用python实现netcat

以下是Python实现Netcat的样例代码：

import argparse
import socket
import threading
import subprocess

def send_recv(sock):
    while True:
        data = sock.recv(1024)
        if not data:
            break
        sock.sendall(data)
        print(data.decode())

def listen(port):
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.bind(('0.0.0.0', port))
    sock.listen(1)
    conn, addr = sock.accept()
    print(f'Connected by {addr}')
    send_recv(conn)
    conn.close()

def connect(host, port):
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.connect((host, port))
    send_recv(sock)
    sock.close()

def execute(cmd):
    result = subprocess.check_output(cmd, shell=True)
    return result

def main():
    parser = argparse.ArgumentParser(description='Netcat')
    parser.add_argument('-l', '--listen', action='store_true', help='listen mode')
    parser.add_argument('-c', '--connect', metavar='HOST', help='connect mode')
    parser.add_argument('-p', '--port', type=int, default=8888, help='port')
    parser.add_argument('-e', '--execute', metavar='CMD', help='execute command')
    args = parser.parse_args()

    if args.listen:
        listen(args.port)
    elif args.connect:
        connect(args.connect, args.port)
    elif args.execute:
        result = execute(args.execute)
        print(result.decode())

if __name__ == '__main__':
    main()

使用方法：

- 监听模式：`python netcat.py -l -p 8888`
- 连接模式：`python netcat.py -c 127.0.0.1 -p 8888`
- 执行命令：`python netcat.py -e "ls -la"`