C# 中的 Java AES/CBC/PKCS5Padding

Question

我收到了需要转换为 C# 的 Java 加密代码。我想我已经很接近了...但我不知道如何复制 IV 计算...有什么帮助吗？

Java 代码:

    public static string getAESencodingResult(String sSrc, String encrypt_key)
    {
        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        byte[] raw = encrypt_key.getBytes();
        SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
        IvParameterSpec iv = new IvParameterSpec(encrypt_key.getBytes());
        cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);
        byte[] encrypted = cipher.doFinal(sSrc.getBytes("utf-8"));
        return new BASE64Encoder().encode(encrypted);
    }

C# 代码:

    static string EncryptStringToBytes(string plainText, byte[] key)
    {
        byte[] encrypted;
        using (RijndaelManaged rijAlg = new RijndaelManaged())
        {
            rijAlg.Key = key;
            // rijAlg.IV = ???
            rijAlg.GenerateIV();
            rijAlg.Padding = PaddingMode.PKCS7;
            rijAlg.Mode = CipherMode.CBC;
            ICryptoTransform encryptor = rijAlg.CreateEncryptor(rijAlg.Key, rijAlg.IV);
            using (MemoryStream msEncrypt = new MemoryStream())
            using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
            using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
            {

                swEncrypt.Write(plainText);
                if (plainText.Length < 16)
                {
                    for (int i = plainText.Length; i < 16; i++)
                        swEncrypt.Write((byte)0x0);
                }
                swEncrypt.Flush();
                csEncrypt.FlushFinalBlock();
                encrypted = msEncrypt.ToArray();
            }
        }
        return Convert.ToBase64String(encrypted);
    }

Answer 1

如果我没有误解 Java 代码，您只需将键值分配给 IV:

rijAlg.Key = key;
rijAlg.IV = key;

并删除GenerateIV行:

rijAlg.GenerateIV();

我知道您无法控制 Java 代码，因此您无法修复此问题，但对于 future 的读者:您不应该在每次加密某些内容时都使用相同的 IV。请参阅this question了解更多信息。