DES将Java解密/加密为python（帮助翻译）

Question

我需要将Java中的简短代码转换为python 3。

import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.SecretKeySpec;

public class DesEncrypterPdys {
    private static DesEncrypterPdys desEncrypter;
    private static Cipher ecipher;
    private static Cipher dcipher;

    private DesEncrypterPdys() throws DesEncrypterException{
        try {
            if(ecipher == null || dcipher == null){
                String cryptoKey;
                cryptoKey = "RAMPOLO S.O. Plokity Lopiokiujhygh ;)";

                SecretKey k = SecretKeyFactory.getInstance("DES").generateSecret(new DESKeySpec(cryptoKey.getBytes()));

                ecipher = Cipher.getInstance("DES");
                dcipher = Cipher.getInstance("DES");
                ecipher.init(Cipher.ENCRYPT_MODE, k);
                dcipher.init(Cipher.DECRYPT_MODE, k);
            }
        }catch (Exception e) {
            throw new DesEncrypterException(e);
        }
    }

    public static DesEncrypterPdys getInstance() throws DesEncrypterException{
        if (desEncrypter == null || ecipher == null || dcipher == null) {
            desEncrypter = new DesEncrypterPdys();
        }
        return desEncrypter;
    }

    public String encrypt(String str) throws DesEncrypterException{
        try {
            if(str == null) return null;
            // Encode the string into bytes using utf-8
            byte[] utf8 = str.getBytes("UTF8");

            // Encrypt
            byte[] enc = ecipher.doFinal(utf8);

            // Encode bytes to base64 to get a string

            return new sun.misc.BASE64Encoder().encode(enc);
        } catch (javax.crypto.BadPaddingException e) {
            throw new DesEncrypterException(e);
        } catch (IllegalBlockSizeException e) {
            throw new DesEncrypterException(e);
        }
        catch (java.io.IOException e) {
            throw new DesEncrypterException(e);
        }
    }

    public String decrypt(String str) throws DesEncrypterException{
        try {
            if(str == null) return null;
            // Decode base64 to get bytes
            byte[] dec = new sun.misc.BASE64Decoder().decodeBuffer(str);

            // Decrypt
            byte[] utf8 = dcipher.doFinal(dec);

            // Decode using utf-8
            return new String(utf8, "UTF8");

        } catch (javax.crypto.BadPaddingException e) {
            throw new DesEncrypterException(e);
        } catch (IllegalBlockSizeException e) {
            throw new DesEncrypterException(e);
        } catch (java.io.IOException e) {
            throw new DesEncrypterException(e);
        }
    }

}

我试图使用类似这样的东西：

import pyDes as pds
import base64 as b64


cryptoKey = "RAMPOLO S.O. Plokity Lopiokiujhygh ;)";
data = b" " # here should be a data for decrypting

k = pds.des(secretKey, pds.ECB, b"\0\0\0\0\0\0\0\0", pad=None, padmode=pds.PAD_PKCS5)
d = k.encrypt(data)
print("Encrypted: %r" % d)
print("Decrypted: %r" % k.decrypt(d))
print(b64.b64encode(d))

但不幸的是没有运气：/

我想收到的是一个简短的程序，用于加密和解码密码。不幸的是，我遇到了太长的cryptokey（？）问题。一旦我能够翻译一段类似的代码，但是幸运的是，旧案例与pydes文档中的案例相对应。现在不一样了...有人可以帮助我将此Java代码翻译为python吗？

Answer 1

运行代码时，返回的错误是：

>>> import pyDes as pds
>>> import base64 as b64
>>> cryptoKey = "RAMPOLO S.O. Plokity Lopiokiujhygh ;)"
>>> data = b"qwertyuiop" # Random gibberish
>>> k = pds.des(cryptoKey, pds.ECB, b"\0\0\0\0\0\0\0\0", pad=None, padmode=pds.PAD_PKCS5)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/dist-packages/pyDes.py", line 400, in __init__
    raise ValueError("Invalid DES key size. Key must be exactly 8 bytes long.")
ValueError: Invalid DES key size. Key must be exactly 8 bytes long.

如果您查看pyDES的Github文档，它指定对于DES加密，密钥应为8字节长，而您的则更长。您需要使用较短的密钥，然后它才能正常工作。

>>> k = pds.des('12345678', pds.ECB, b"\0\0\0\0\0\0\0\0", pad=None, padmode=pds.PAD_PKCS5)
>>> k
<pyDes.des object at 0x7fc4ade1f9d0>

重要的旁注，从安全角度来看，您应该避免使用DES，因为它已完全破坏了当今的标准，即使是Wikipedia page（这不是加密知识的重要来源）也表明DES破解是可行的。由于每个块都以完全相同的方式加密，因此ECB模式也无法提供任何安全保证，因此它也被破坏了，请检查this。