Question

我在C＃

中遇到AES Rijndael管理加密问题

我有一个大约110,000个图像文件名的列表，我想单独加密。我编写了一个算法，一起加密它们，然后是一个解密单个图像的方法。

加密方法如下：

var saltBytes = Encoding.UTF8.GetBytes(salt);

// The key size for encrypting the images
int KEY_SIZE = 256;

// The initialization vector for encrypting the images
byte[] _initialisationVectorBytes = Encoding.ASCII.GetBytes("EAzjVfNrCzOoE7AI");

//Derives the key from the phrase and the salt
using(var password = new Rfc2898DeriveBytes(password, saltBytes))
{
    //use the AES Rijndael algorithm
    using(var symmetricKey = new RijndaelManaged())
    {
        //set the mode
        symmetricKey.Mode = CipherMode.CBC;

        //create an encryption object
        using(var encryptor = symmetricKey.CreateEncryptor(password.GetBytes(KEY_SIZE / 8), _initialisationVectorBytes))
        {
            //loop through the images
            Parallel.ForEach(_sourceImages, image =>
            {
                //set the plain text bytes and the salt bytes
                var plainTextBytes = Encoding.UTF8.GetBytes(image.ImageID.ToString());
                var cipherText = string.Empty;

                if(_encryptImageFilenames)
                {
                    //create a memory stream
                    using(var cryptoMemoryStream = new MemoryStream())
                    {
                        //create a cryptographic stream
                        using(var cryptoStream = new CryptoStream(cryptoMemoryStream, encryptor, CryptoStreamMode.Write))
                        {
                            //encrypt the image id
                            cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
                            cryptoStream.FlushFinalBlock();
                            cipherText = Convert.ToBase64String(cryptoMemoryStream.ToArray());
                        }
                    }
                }
                else
                    cipherText = image.ImageID.ToString();
            }
        }
    }
}

据我所知，这很有效。但是，当我运行以下解密方法时，绝大多数图像都正确解密，但是有些图像使用奇怪的字符进行了不正确的解密，有些图像提供了“填充无效且无法删除”错误。

// The size of the key
const int KeySize = 256;

// Use the Rijndael Managed algorithm
RijndaelManaged SymmetricKey = new RijndaelManaged();

// The initialisation vector
byte[] initialisationVectorBytes = Encoding.ASCII.GetBytes("EAzjVfNrCzOoE7AI");

try
{
    //get the cipher text bytes and the salt bytes
    var cipherTextBytes = Convert.FromBase64String(cipherText);

    //Derives the key from the phrase and the salt
    using(var password = new Rfc2898DeriveBytes(passPhrase, Encoding.UTF8.GetBytes(salt)))
    {
        //set the mode
        SymmetricKey.Mode = CipherMode.CBC;

        //create an decryption object
        using(var decryptor = SymmetricKey.CreateDecryptor(password.GetBytes(KeySize / 8), initialisationVectorBytes))
        {
            //create a memory stream
            using(var memoryStream = new MemoryStream(cipherTextBytes))
            {
                //create a crypto stream
                using(var cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read))
                {
                    //decrypt the string
                    var plainTextBytes = new byte[cipherTextBytes.Length];
                    var decryptedByteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length);
                    return Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount);
                }
            }
        }
    }
}
catch(Exception ex)
{
    return string.Empty;
}

因此，对于110000张图像，我获得了大约20-30张图像的成功解密，失败是之前两个错误中的一个。

我不能为我的生活看到为什么如果加密方法中出现错误肯定会影响所有已加密的图像？

一些例子：

明文= 128784

Ciphertext = J2W / 5Y1 / nvnrpvaWIZhl6g ==

Decrypted = 128784

明文= 122875

Ciphertext = N + heUx57427Lk8 / Ew10rsA ==

解密= \ u0001 \ u0017275

明文= 121693

Ciphertext = Zf70jcYCbHQqhd23NqD6yA ==

Decrypted = 121693

明文= 133456

Ciphertext = wzBgoDaTnGBEyQokI + l6Uw ==

Decrypted = “填充无效，无法删除”

这些示例中使用的密码和盐是：

密码 =“！XbLg`p / 0.9nyF ?; jGf @ nA; e19'TtVk？Ik.l * 2 = zy.9MYH：7Jmj [| * 0N！”

盐 =“alkfdslkaj：H6D£ rWe！N，K;？sdoidnalks34334234 ＆amp;（*£';”

Rijndael管理问题

0 个答案: