关于3DES的解密,求助啊...

Question

public byte[] Decrypt3DES(string a_strString, string a_strKey) //解密
    {
        TripleDESCryptoServiceProvider DES = new TripleDESCryptoServiceProvider();
        DES.Key = Convert.FromBase64String(a_strKey);
        DES.Mode = CipherMode.ECB;
        DES.Padding = PaddingMode.PKCS7;        ICryptoTransform DESDecrypt = DES.CreateDecryptor();
        byte[] result;
        try
        {
            byte[] Buffer = Encoding.UTF8.GetBytes(a_strString);
            result = DESDecrypt.TransformFinalBlock(Buffer, 0, Buffer.Length);
        }
        catch (Exception e)
        {
            throw (new Exception("不是有效的 base64 字符串:{0}", e));
        }
        return result;
    }
运行后报Length of the data to decrypt is invalid.的错误...求助啊...这个大概是因为啥引起的?有嘛解决办法啊?
JAVA的解密方式是:public static String desDecrypt(String cipherText, String keyValue) throws Exception { BASE64Decoder base64d = new BASE64Decoder();
DESedeKeySpec p8ksp = null;
p8ksp = new DESedeKeySpec(base64d.decodeBuffer(keyValue));
Key key = SecretKeyFactory.getInstance("DESede").generateSecret(p8ksp); Cipher cipher = null;
byte[] inPut = base64d.decodeBuffer(cipherText);
// “算法/模式/填充”
cipher = Cipher.getInstance("DESede/ECB/PKCS5Padding");
SecretKeySpec myKey = new SecretKeySpec(key.getEncoded(), "DESede");
// IvParameterSpec ivspec = new IvParameterSpec(myIV);
cipher.init(2, myKey);
byte[] output = cipher.doFinal(inPut);
return new String(output, "UTF8");
}

Answer 1

byte[] Buffer = Convert.FromBase64String(a_strString);

Answer 2

byte[] Buffer = Convert.FromBase64String(a_strString);的话  会报
The input is not a valid Base-64 string as it contains a non-base 64 character, more than two padding characters, or a non-white space character among the padding characters.
我肯定是试过这样做的...如果用Convert.FromBase64String的话,这句就抛异常了,如果用Encoding.UTF8.GetBytes还可以执行到result = DESDecrypt.TransformFinalBlock(Buffer, 0, Buffer.Length);这说明转换出来的byte数组是正确的 而Convert出来的是错误的.

Answer 3

byte[] inPut = base64d.decodeBuffer(cipherText);看到JAVA怎么做了么？"The input is not a valid Base-64 string..."说明你的数据有问题。

Answer 4

 /// <summary>
        /// DES 加密(数据加密标准，速度较快，适用于加密大量数据的场合)
        /// </summary>
        /// <param name="EncryptString">待加密的密文</param>
        /// <param name="EncryptKey">加密的密钥</param>
        /// <returns>returns</returns>
        public static string DESEncrypt(string EncryptString, string EncryptKey)
        {
            if (string.IsNullOrEmpty(EncryptString)) { throw (new Exception("密文不得为空")); }            if (string.IsNullOrEmpty(EncryptKey)) { throw (new Exception("密钥不得为空")); }            if (EncryptKey.Length != 8) { throw (new Exception("密钥必须为8位")); }            byte[] m_btIV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };            string m_strEncrypt = "";            DESCryptoServiceProvider m_DESProvider = new DESCryptoServiceProvider();            try
            {
                byte[] m_btEncryptString = Encoding.Default.GetBytes(EncryptString);                MemoryStream m_stream = new MemoryStream();                CryptoStream m_cstream = new CryptoStream(m_stream, m_DESProvider.CreateEncryptor(Encoding.Default.GetBytes(EncryptKey), m_btIV), CryptoStreamMode.Write);                m_cstream.Write(m_btEncryptString, 0, m_btEncryptString.Length);                m_cstream.FlushFinalBlock();                m_strEncrypt = Convert.ToBase64String(m_stream.ToArray());                m_stream.Close(); m_stream.Dispose();                m_cstream.Close(); m_cstream.Dispose();
            }
            catch (IOException ex) { throw ex; }
            catch (CryptographicException ex) { throw ex; }
            catch (ArgumentException ex) { throw ex; }
            catch (Exception ex) { throw ex; }
            finally { m_DESProvider.Clear(); }            return m_strEncrypt;
        }  /// <summary>
        /// DES 解密(数据加密标准，速度较快，适用于加密大量数据的场合)
        /// </summary>
        /// <param name="DecryptString">待解密的密文</param>
        /// <param name="DecryptKey">解密的密钥</param>
        /// <returns>returns</returns>
        public static string DESDecrypt(string DecryptString, string DecryptKey)
        {
            if (string.IsNullOrEmpty(DecryptString)) { throw (new Exception("密文不得为空")); }            if (string.IsNullOrEmpty(DecryptKey)) { throw (new Exception("密钥不得为空")); }            if (DecryptKey.Length != 8) { throw (new Exception("密钥必须为8位")); }            byte[] m_btIV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };            string m_strDecrypt = "";            DESCryptoServiceProvider m_DESProvider = new DESCryptoServiceProvider();            try
            {
                byte[] m_btDecryptString = Convert.FromBase64String(DecryptString);                MemoryStream m_stream = new MemoryStream();
                
                CryptoStream m_cstream = new CryptoStream(m_stream, m_DESProvider.CreateDecryptor(Encoding.Default.GetBytes(DecryptKey), m_btIV), CryptoStreamMode.Write);                m_cstream.Write(m_btDecryptString, 0, m_btDecryptString.Length);                m_cstream.FlushFinalBlock();                m_strDecrypt = Encoding.Default.GetString(m_stream.ToArray());                m_stream.Close(); m_stream.Dispose();                m_cstream.Close(); m_cstream.Dispose();
            }
            catch (IOException ex) { throw ex; }
            catch (CryptographicException ex) { throw ex; }
            catch (ArgumentException ex) { throw ex; }
            catch (Exception ex) { throw ex; }
            finally { m_DESProvider.Clear(); }            return m_strDecrypt;
        }