CryptoStream 报错 Padding is invalid and cannot be removed

Question

我的代码有问题。函数 Decryptor 出现问题。

FlushFinalBlock 抛出 "Padding is invalid and cannot be removed"

在函数 Decryptor 中，我得到长度为 6048 的 myData，当行 cryptoStream.Write(myData, 0, myData.Length);完成后我在 memoryStream 中得到长度 6032 然后是行 cryptoStream.FlushFinalBlock();抛出错误 "Padding is invalid and cannot be removed."

如您所见，我正在使用 Padding = PaddingMode.PKCS7;

static RijndaelManaged rmCrypto;
static object lockCryptoStream = new object();

public static void SetrmCrypto()
{
    rmCrypto = new RijndaelManaged();
    rmCrypto.Padding = PaddingMode.PKCS7;
    rmCrypto.KeySize = 128;
    rmCrypto.Key = new ASCIIEncoding().GetBytes("xxxxxxxxxxxxxxxx");
    rmCrypto.IV = new ASCIIEncoding().GetBytes("yyyyyyyyyyyyyyyy");
}

public static byte[] Encryptor(byte[] myData)
{
    lock (lockCryptoStream)
    {
        using (var memoryStream = new MemoryStream())
        {
            using (var cryptoStream = new CryptoStream(memoryStream, rmCrypto.CreateEncryptor(rmCrypto.Key, rmCrypto.IV), CryptoStreamMode.Write))
            {
                cryptoStream.Write(myData, 0, myData.Length);
                cryptoStream.FlushFinalBlock();
                cryptoStream.Close();
                return memoryStream.ToArray();
            }
        }
    }
}

public static byte[] Decryptor(byte[] myData)
{
    lock (lockCryptoStream)
    {
        using (var memoryStream = new MemoryStream())
        {
            using (var cryptoStream = new CryptoStream(memoryStream, rmCrypto.CreateDecryptor(rmCrypto.Key, rmCrypto.IV), CryptoStreamMode.Write))
            {
                cryptoStream.Write(myData, 0, myData.Length);
                cryptoStream.FlushFinalBlock();
                cryptoStream.Close();
                return memoryStream.ToArray();
            }
        }
    }
}

服务器使用加密器，数据通过UDP发送。客户端使用 Decryptor 而不是解密数据。代码适用于大多数数据包，可以说它可以工作几个小时，但之后我在法拉盛上遇到了那个错误。

Answer 1

上面的代码效果很好。在我的案例中，问题出在用 C++ 键入的服务器上，我在加密方面遇到了问题（接收和发送时的线程问题）

CryptoStream 报错 Padding is invalid and cannot be removed

CryptoStream error Padding is invalid and cannot be removed

c#

rijndaelmanaged

cryptostream

pkcs#7