使用Aes加密对字符串进行加密和解密-C＃

Question

我想将一个加密的字符串作为字节数组存储在SQL数据库中，但无法弄清楚自己在做什么错。 代码是这样的：

    private void loginBtn_Click(object sender, EventArgs e)
    {
        try
        {
            string password = passwordBox.Text.ToString();

            using (Aes algorithm = Aes.Create())
            {
                byte[] encryptedPassword = EncryptString(password, algorithm.Key, algorithm.IV);

                string roundTrip = DecryptString(encryptedPassword, algorithm.Key, algorithm.IV);

                MessageBox.Show("Encrypted Password: " + encryptedPassword.ToString() + '\n' + "Round Trip: " + roundTrip.ToString());
            }
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
    }

用于'EncryptString'和'DecryptString'的代码是Microsoft的Aes类参考 （该示例位于页面末尾）中的代码。

我执行了我的代码，在消息框中提供的所有内容是这样的：

加密密码：System.Byte []

往返：（空白处）

    static byte[] EncryptString(string str, byte[] key, byte[] IV)
    {
        if (str == null || str.Length <= 0)
            throw new ArgumentNullException("string");
        if (key == null || key.Length <= 0)
            throw new ArgumentNullException("key");
        if (IV == null || IV.Length <= 0)
            throw new ArgumentNullException("IV");

        byte[] encrypted;

        using (Aes algorithm = Aes.Create())
        {
            algorithm.Key = key;
            algorithm.IV = IV;

            ICryptoTransform encryptor = algorithm.CreateEncryptor(algorithm.Key, algorithm.IV);

            using (MemoryStream msEncrypt = new MemoryStream())
            {
                using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                {
                    using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                    {
                        swEncrypt.Write(str);
                    }
                    encrypted = msEncrypt.ToArray();
                }
            }
        }

        return encrypted;
    }

    static string DecryptString(byte[] cipher, byte[] key, byte[] IV)
    {
        if (cipher == null || cipher.Length <= 0)
            throw new ArgumentNullException("cipher");
        if (key == null || key.Length <= 0)
            throw new ArgumentNullException("key");
        if (IV == null || IV.Length <= 0)
            throw new ArgumentNullException("IV");

        string decrypted;

        using (Aes algorithm = Aes.Create())
        {
            algorithm.Key = key;
            algorithm.IV = IV;

            ICryptoTransform decryptor = algorithm.CreateDecryptor(algorithm.Key, algorithm.IV);

            using (MemoryStream msDecrypt = new MemoryStream())
            {
                using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                {
                    using (StreamReader srDecrypt = new StreamReader(csDecrypt))
                    {
                        decrypted = srDecrypt.ReadToEnd();
                    }
                }
            }
        }

        return decrypted;
    }

有人可以帮我解决这个问题吗？

PS文本框的密码字符设置为*

Answer 1

在DecryptString方法中，您忘记将cipher参数传递给msDecrypt内存流的构造函数作为输入，因此该方法实际上解密了空的输入流，因此结果也为空。

线

using (MemoryStream msDecrypt = new MemoryStream())

实际上应该是：

using (MemoryStream msDecrypt = new MemoryStream(cipher))

然后一切正常。