用Python解密Windows EC2密码

Question

我想启动一个WindowsEC2实例，并使用Python以编程方式获取管理员密码。我知道这可以通过像这样的CLI来完成，但我更愿意在本地解密，以避免通过internet发送私钥

aws ec2 get-password-data --instance-id i-0d4d8273cadcae0a0 --priv-launch-key .ssh/elliott2.pem

在阅读Cryptodome文档后，我试着这样做：

import boto3
from Crypto.PublicKey import RSA
from Crypto.Cipher import PKCS1_OAEP

ec2 = boto3.resource('ec2', 'us-west-2')
i = ec2.Instance('i-028dee2acb533fc59')

encrypted_str = i.password_data()['PasswordData']
with open('mykey.pem') as fp:
  key = RSA.importKey(fp.read())

cipher = PKCS1_OAEP.new(key)
print(cipher.decrypt(enc_str))

此操作失败并出现错误：

Traceback (most recent call last):
  File "test.py", line 14, in <module>
    print(cipher.decrypt(encrypted_str))
  File "/Users/elliott/Library/Python/3.8/lib/python/site-packages/Crypto/Cipher/PKCS1_OAEP.py", line 167, in decrypt
    raise ValueError("Ciphertext with incorrect length.")
ValueError: Ciphertext with incorrect length.

我认为cipherkey必须正好是256字节。但是密码数据比这个长，所以我不知道该怎么办