将 RSA 解密从 PyCrypto 迁移到 PyCryptodome

Question

使用 PyCrypto 库，以下代码打印 127:

from Crypto.PublicKey import RSA
import base64

# Private key in tuple form (obscured for privacy)
key = [1, 1, 1]

bk = "zJuG60z9Iv..." # (obscured for privacy)

privatekey = RSA.construct(key)
result = privatekey.decrypt(base64.b64decode(bk))
print(len(result))

据我所知，这相当于使用 PyCryptodome。但是得到的值只有16的长度，说明可能存在解密错误

from Crypto.PublicKey import RSA
from Crypto.Cipher import PKCS1_v1_5
import base64

# Private key in tuple form (obscured for privacy)
key = [1, 1, 1]

bk = "zJuG60z9Iv..." # (obscured for privacy)

privatekey = RSA.construct(key)
cipher = PKCS1_v1_5.new(privatekey)
result = cipher.decrypt(base64.b64decode(bk), None)
print(len(result))

我相信这是因为我的密文使用了教科书未填充的 RSA。有谁知道我如何使用 PyCryptodome 或其他维护的库解密此值？

Answer 1

PyCryptodome 不提供解密教科书 RSA 的内置方法，但可以使用标准库中的模幂来解密。

from Crypto.PublicKey import RSA
import base64

# Private key in tuple form (obscured for privacy)
key = [1, 1, 1]

bk = "zJuG60z9Iv..." # (obscured for privacy)

privatekey = RSA.construct(key)
ciphertext = base64.b64decode(bk)
ct_int = int.from_bytes(ciphertext, 'big')
pt_int = pow(ct_int, privatekey.d, privatekey.n)
plaintext = pt_int.to_bytes(privatekey.size_in_bytes(), 'big').lstrip(b'\x00')
print(len(plaintext))

将 RSA 解密从 PyCrypto 迁移到 PyCryptodome

Migrate RSA decryption from PyCrypto to PyCryptodome

python

pycrypto

pycryptodome