AES加密-解密问题:填充无效，无法删除

Question

我面临AES填充问题。我使用的是Alcides Soares FIlho（用C#生成128位字符串）中建议的代码。请注意，我的加密侧码是。。。

private string Encrypt(string clearText)
         {

             string EncryptionKey = "I love chocolate";
             byte[] clearBytes = 
System.Text.Encoding.Unicode.GetBytes(clearText);
             using (Aes encryptor = Aes.Create())
             {

                 Rfc2898DeriveBytes pdb = new 
Rfc2898DeriveBytes(EncryptionKey, new byte[] { 0x49, 0x76, 0x61, 0x6e, 
0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
                 encryptor.Key = pdb.GetBytes(32);
                 encryptor.IV = pdb.GetBytes(16);
                 using (MemoryStream ms = new MemoryStream())
                 {
                     using (CryptoStream cs = new CryptoStream(ms, 
encryptor.CreateEncryptor(), CryptoStreamMode.Write))
                     {
                         cs.Write(clearBytes, 0, clearBytes.Length);
                         cs.Close();
                     }
                     clearText = Convert.ToBase64String(ms.ToArray());
                 }
             }
             return clearText;
         }

另外，我传递给明文的值是“Z4YAZZSQ 001F295E2589AWAN HANS”。加密正在进行。但解密失败了。

解密侧码

private string Decrypt(string cipherText)
    {
        string EncryptionKey = "I love chocolate";
        byte[] cipherBytes = Convert.FromBase64String(cipherText);
        using (Aes encryptor = Aes.Create())
        {

            Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, 
new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 
0x64, 0x65, 0x76 });
            encryptor.Key = pdb.GetBytes(32);
            encryptor.IV = pdb.GetBytes(16);
            using (MemoryStream ms = new MemoryStream())
            {
                using (CryptoStream cs = new CryptoStream(ms, 
encryptor.CreateDecryptor(), CryptoStreamMode.Write))
                {
                    cs.Write(cipherBytes, 0, cipherBytes.Length);
                    cs.Close();
                }
                cipherText = 
System.Text.Encoding.Unicode.GetString(ms.ToArray());
            }
        }
        return cipherText;
    }

我应该能拿回“Z4YAZZSQ 001F295E2589AWAN HANS”

但出现以下错误“填充无效，无法删除”请建议解决方案。

Answer 1

无论何时使用填充，都需要进行最后一次调用，让代码知道是时候添加填充了。这就是为什么您需要调用FlushFinalBlock。