c# AES Decryption

我正在使用SagePay Forms，目前正在将它们的VB示例转换为c#。我已经取得了很好的进展，所以我项目的加密部分运行良好（SagePay可以解密它）。

我遇到的问题是，当我试图解密字符串时，它会变成垃圾。如果有人以前做过这件事，我会非常感谢对我的解密代码的帮助。我已经包含了有效的加密代码，前两行是另一个方法的设置和调用。

我还没有添加VB代码，但如果这是必需的，我可以添加它。如果不需要的话，我不想要一个巨大的帖子。

实用方法：

public string byteArrayToHexString(byte[] ba)
    {
    return BitConverter.ToString(ba).Replace("-", "");
    }
public static byte[] StringToByteArray(string hex)
    {
        return Enumerable.Range(0, hex.Length)
                         .Where(x => x % 2 == 0)
                         .Select(x => Convert.ToByte(hex.Substring(x, 2), 16))
                         .ToArray();
    }

主加密方法，前几行是从一个较大的方法中提取的调用。

string crypt = "blahblahblah"
string EncryptAndEncode = "@" + byteArrayToHexString(aesEncrypt(crypt));

        private byte[] aesEncrypt(string inputText)
    {
        RijndaelManaged AES = new RijndaelManaged();
        //set the mode, padding and block size for the key
        AES.Padding = PaddingMode.PKCS7;
        AES.Mode = CipherMode.CBC;
        AES.KeySize = 128;
        AES.BlockSize = 128;
        //convert key and plain text input into byte arrays
        Byte[] keyAndIvBytes = UTF8Encoding.UTF8.GetBytes("tR7nR6wZHGjYMCuV");
        Byte[] inputBytes = UTF8Encoding.UTF8.GetBytes(inputText);//AbHLlc5uLone0D1q
        //create streams and encryptor object
        MemoryStream memoryStream = new MemoryStream();
        CryptoStream cryptoStream = new CryptoStream(memoryStream, AES.CreateEncryptor(keyAndIvBytes, keyAndIvBytes), CryptoStreamMode.Write);
        //perform encryption
        cryptoStream.Write(inputBytes, 0, inputBytes.Length);
        cryptoStream.FlushFinalBlock();
        //get encrypted stream into byte array
        Byte[] outBytes = memoryStream.ToArray();
        //close streams
        memoryStream.Close();
        cryptoStream.Close();
        AES.Clear();
        return outBytes;
    }

的解码和解密方法

public string DecodeAndDecrypt(string strIn)
    {
        //** HEX decoding then AES decryption, CBC blocking with PKCS5 padding - DEFAULT **

        string DecodeAndDecrypt = aesDecrypt(StringToByteArray(strIn.Substring(1)));
        return (DecodeAndDecrypt);
    }
    private string aesDecrypt(Byte[] inputBytes)
    {
    RijndaelManaged AES = new RijndaelManaged();
    Byte[] keyAndIvBytes = UTF8Encoding.UTF8.GetBytes("tR7nR6wZHGjYMCuV");
    Byte[] outputBytes = inputBytes;//Convert.FromBase64String(inputBytes);
    //set the mode, padding and block size
    AES.Padding = PaddingMode.PKCS7;
    AES.Mode = CipherMode.CBC;
    AES.KeySize = 128;
    AES.BlockSize = 128;
    //create streams and decryptor object
    MemoryStream memoryStream = new MemoryStream(outputBytes);
    CryptoStream cryptoStream = new CryptoStream(memoryStream, AES.CreateEncryptor(keyAndIvBytes, keyAndIvBytes), CryptoStreamMode.Read);
    //perform decryption
    cryptoStream.Read(outputBytes, 0, outputBytes.Length);
    Trace.WriteLine(outputBytes);
    //close streams
    memoryStream.Close();
    cryptoStream.Close();
    AES.Clear();
    //return System.Text.Encoding.UTF8.GetString(outputBytes);
    string plainText = Encoding.UTF8.GetString(outputBytes,
                                   0,
                                   outputBytes.Length);
    return plainText;
    }

public static class EncryptionHelper
{
    private static byte[] keyAndIvBytes;
    static EncryptionHelper()
    {
        // You'll need a more secure way of storing this, I hope this isn't
        // the real key
        keyAndIvBytes = UTF8Encoding.UTF8.GetBytes("tR7nR6wZHGjYMCuV");
    }
    public static string ByteArrayToHexString(byte[] ba)
    {
        return BitConverter.ToString(ba).Replace("-", "");
    }
    public static byte[] StringToByteArray(string hex)
    {
        return Enumerable.Range(0, hex.Length)
                         .Where(x => x % 2 == 0)
                         .Select(x => Convert.ToByte(hex.Substring(x, 2), 16))
                         .ToArray();
    }
    public static string DecodeAndDecrypt(string cipherText)
    {
        string DecodeAndDecrypt = AesDecrypt(StringToByteArray(cipherText));
        return (DecodeAndDecrypt);
    }
    public static string EncryptAndEncode(string plaintext)
    {
        return ByteArrayToHexString(AesEncrypt(plaintext));
    }
    public static string AesDecrypt(Byte[] inputBytes)
    {
        Byte[] outputBytes = inputBytes;
        string plaintext = string.Empty;
        using (MemoryStream memoryStream = new MemoryStream(outputBytes))
        {
            using (CryptoStream cryptoStream = new CryptoStream(memoryStream, GetCryptoAlgorithm().CreateDecryptor(keyAndIvBytes, keyAndIvBytes), CryptoStreamMode.Read))
            {
                using (StreamReader srDecrypt = new StreamReader(cryptoStream))
                {
                    plaintext = srDecrypt.ReadToEnd();
                }
            }
        }
        return plaintext;
    }
    public static byte[] AesEncrypt(string inputText)
    {
        byte[] inputBytes = UTF8Encoding.UTF8.GetBytes(inputText);//AbHLlc5uLone0D1q
        byte[] result = null;
        using (MemoryStream memoryStream = new MemoryStream())
        {
            using (CryptoStream cryptoStream = new CryptoStream(memoryStream, GetCryptoAlgorithm().CreateEncryptor(keyAndIvBytes, keyAndIvBytes), CryptoStreamMode.Write))
            {
                cryptoStream.Write(inputBytes, 0, inputBytes.Length);
                cryptoStream.FlushFinalBlock();
                result = memoryStream.ToArray();
            }
        }
        return result;
    }

    private static RijndaelManaged GetCryptoAlgorithm()
    {
        RijndaelManaged algorithm = new RijndaelManaged();
        //set the mode, padding and block size
        algorithm.Padding = PaddingMode.PKCS7;
        algorithm.Mode = CipherMode.CBC;
        algorithm.KeySize = 128;
        algorithm.BlockSize = 128;
        return algorithm;
    }
}

string crypt = "blahblahblah";
string EncryptAndEncode = EncryptionHelper.EncryptAndEncode(crypt);            
Console.WriteLine(EncryptAndEncode);
Console.WriteLine(EncryptionHelper.DecodeAndDecrypt(EncryptAndEncode));
Console.ReadLine();