从点网到Java的AES 256解密

Question

I have below do not code and trying to convert the same to java , but the result of the bot are quite different, In Dot net i get the actual value but in the Java i get the value result with same length but the values differs. The Decryption technique used is AES 256 , May i know where I am going wrong in the java code.

Dot Net Code:

public static string AESDecryptText(string input, string key)
    {
        // Get the bytes of the string
        byte[] bytesToBeDecrypted = Convert.FromBase64String(input);
        byte[] keyBytes = Encoding.UTF8.GetBytes(key);
        keyBytes = SHA256.Create().ComputeHash(keyBytes);

        byte[] bytesDecrypted = AESDecrypt(bytesToBeDecrypted, keyBytes);

        string result = Encoding.UTF8.GetString(bytesDecrypted);

        return result;
    }

    private static byte[] AESDecrypt(byte[] bytesToBeDecrypted, byte[] keyBytes)
    {
        byte[] decryptedBytes = null;

        // Set your salt here, change it to meet your flavor:
        // The salt bytes must be at least 8 bytes.
        byte[] saltBytes = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8 };

        using (MemoryStream ms = new MemoryStream())
        {
            using (RijndaelManaged AES = new RijndaelManaged())
            {
                AES.KeySize = 256;
                AES.BlockSize = 128;

                var key = new Rfc2898DeriveBytes(keyBytes, saltBytes, 1000);
                AES.Key = key.GetBytes(AES.KeySize / 8);
                AES.IV = key.GetBytes(AES.BlockSize / 8);

                AES.Mode = CipherMode.CBC;

                using (var cs = new CryptoStream(ms, AES.CreateDecryptor(), CryptoStreamMode.Write))
                {
                    cs.Write(bytesToBeDecrypted, 0, bytesToBeDecrypted.Length);
                    cs.Close();
                }
                decryptedBytes = ms.ToArray();
            }
        }

        return decryptedBytes;
    }

Below the Java Code :

byte[] salt = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8 };

        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");

        MessageDigest md = MessageDigest.getInstance("SHA-256" );

        md.update(KEY_IV.getBytes( StandardCharsets.UTF_8 ) );
        byte[] hashDigest = md.digest();


        String encryptedHashDigest = Base64.encodeBase64String(hashDigest);

        PBEKeySpec pbeKeySpec = new PBEKeySpec(encryptedHashDigest.toCharArray(),
                salt, 1000, 384);

        Key generatedKey = factory.generateSecret(pbeKeySpec);

        byte[] extractedKey = new byte[32];
        byte[] iv = new byte[16];


        System.arraycopy(generatedKey.getEncoded(), 0, extractedKey, 0, 32);
        System.arraycopy(generatedKey.getEncoded(), 32, iv, 0, 16);


        byte[] base64Decoded = Base64.decodeBase64(toBeDecrypted);

        Cipher c = Cipher.getInstance("AES/CBC/PKCS5Padding");

        c.init(2, new SecretKeySpec(extractedKey, "AES"), new IvParameterSpec(iv));

        byte[] decryptedBytes = c.doFinal(base64Decoded);

        System.out.println("Decrypted " + new String(Base64.encodeBase64(decryptedBytes), StandardCharsets.UTF_8));

Answer 1

Your problem appears to be here:

 byte[] decValue = c.doFinal(decoded);

 System.out.println("Pin "+new String(decValue, StandardCharsets.UTF_8));

You have a byte array: decValue filled with the decrypted bytes. Those bytes may, or may not, have been valid UTF-8 text before they were encrypted. You need to convert those bytes back into the correct format(s) for customerData whatever that is. If it comes from a database, then it may well not be UTF-8 but at least partly in binary. Numbers might be held as raw binary in the database for instance.

You need to check the precise format of the expected data, and convert your decrypted byte array into that same format.