Python和C＃密码学：我做错了什么？

Question

I need to encrypt text in python and decrypt in C #. In python, I have this code:

I have this code in Python:

def genKey():
    rsa = RSA.gen_key(2048, 65537)
    rsa.save_key('c:/temp/priv-key.pem', callback=passwordCallback)
    rsa.save_pub_key('c:/temp/pub-key.pem')

def encrypt():
    varkey = readkey('c:/temp/pub-key.pem')
    bio = BIO.MemoryBuffer(varkey)
    rsa = RSA.load_pub_key_bio(bio)

    encrypted = rsa.public_encrypt('My Text Here.', RSA.pkcs1_oaep_padding)

    f = open("c:/temp/cript.txt", "w")
    f.write(encrypted)
    f.close()

This code uses M2Crypto.

Like I said, I want to decrypt the result generated up in C #. Below is my code:

static void Main(string[] args)
{
    string text = GetText();
    System.Text.ASCIIEncoding  encoding=new System.Text.ASCIIEncoding();
    Byte[] payload = encoding.GetBytes(text);

    byte[] b = System.IO.File.ReadAllBytes(@"C:\temp\priv-key.pem");
    System.Text.ASCIIEncoding enc = new System.Text.ASCIIEncoding();

    OpenSSL.Core.BIO bio = new OpenSSL.Core.BIO(b);
    OpenSSL.Crypto.CryptoKey key = OpenSSL.Crypto.CryptoKey.FromPrivateKey(bio, "mypassword");
    RSA rsa = key.GetRSA();
    byte[] result = rsa.PrivateDecrypt(payload, RSA.Padding.OAEP);
}

The problem is this line:

byte[] result = rsa.PrivateDecrypt(payload, RSA.Padding.OAEP);

When it is executed, this error occurs:

error:0407A079:rsa routines:RSA_padding_check_PKCS1_OAEP:oaep decoding error
error:04065072:rsa routines:RSA_EAY_PRIVATE_DECRYPT:padding check failed

The gurus of Cryptography and C# can help me?

Answer 1

You are writing the encryption ciphertext as text. Instead you should open your file in binary mode in python. Then in C# you do the same thing, but the other way around. Here you should return bytes instead of a string as ciphertext.

If you want to use text mode instead of binary mode then you could use base 64 encoding/decoding.