在 Python Paramiko 中执行 passwd 命令以更改 Linux 服务器上的密码

Question

我正在尝试编写一个 Python 3 脚本以实用 ssh 进入 Linux 服务器并更改密码。我已经使用 Paramiko 模块编写了一个脚本。

我在尝试运行多个 shell 命令时遇到了问题。我的脚本尝试执行命令，但 Paramiko 在一个 shell 命令后超时。

这是我目前正在编写的脚本。任何见解将不胜感激。

import paramiko

def change_pw():
    hostname = "IP" #IP Address of Linux Server
    username = "root" #username
    password = "oldpw!" #password for Linux Server

#NOTE - This variable is suppose to define 3 shell commands. I do not believe the script is sending these commands as listed because the password does not update.
    commands = [
        "passwd",
        "newpw!",
        "newpw!"
    ]

#NOTE - Attempted to utilize '\n' to execute multiple commands and failed
    # commands = [
    #     "passwd \n newpw! \n newpw!"
    # ]

    # initialize the SSH clientp0-
    client = paramiko.SSHClient()
    # add to known hosts
    client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    try:
        client.connect(hostname=hostname, username=username, password=password)
    except:
        print("[!] Cannot connect to the SSH Server")
        exit()

    # execute the commands
    for command in commands:
        print("="*50, command, "="*50)
        stdin, stdout, stderr = client.exec_command(command)
        print(stdout.read().decode())
        err = stderr.read().decode()
        if err:
            print(err)

change_pw()

Answer 1

您没有三个命令。你有一个命令，passwd，它需要两行输入。

这两个问题展示了如何使用 Paramiko 为命令提供输入：

• Pass input/variables to command/script over SSH using Python Paramiko
• Executing command using "su -l" in SSH using Python

所以专门针对passwd，需要使用：

stdin, stdout, stderr = client.exec_command('passwd')
# answer the new password prompts
stdin.write('newpw\n')
stdin.write('newpw\n')
stdin.flush()
# wait for the command to complete a print the output
stdout.channel.set_combine_stderr(True)
print(stdout.read().decode())

关于Channel.set_combine_stderr，请参阅Paramiko ssh die/hang with big output。

---

强制警告：不要使用AutoAddPolicy - 这样做会失去对MITM attacks 的保护。如需正确解决方案，请参阅Paramiko "Unknown Server"。

Answer 2

问题是我试图使用 3 个输入命令来更改 root 的密码。我只需要调用 passwd 命令，然后为“输入新密码”和“确认新密码”传递两个输入变量

import paramiko
import time

hostname = 'IP'
username = 'root'
password = 'oldpw'


commands = ['passwd']



# initialize the SSH clientp
client = paramiko.SSHClient()
# add to known hosts
client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
try:
    client.connect(hostname=hostname, username=username, password=password)
except:
    print("[!] Cannot connect to the SSH Server")
    exit()

# execute the commands
for command in commands:
    print("="*50, 'PW change executed', "="*50)
    stdin, stdout, stderr = client.exec_command(command)
    stdin.write('newpw' '\n' 'newpw' '\n') #input varuables for "Enter new PW" and "re-enter new PW"
    stdin.flush()
    print(stdout.read().decode())
    err = stderr.read().decode()
    if err:
        print(err)