马克斯(优秀)答案的变体

添加“使用” 将类设置为IDisposable 删除URL编码代码以简化示例。 添加一个简单的测试装置来演示使用方法

希望这能有所帮助

[TestFixture]
public class RijndaelHelperTests
{
    [Test]
    public void UseCase()
    {
        //These two values should not be hard coded in your code.
        byte[] key = {251, 9, 67, 117, 237, 158, 138, 150, 255, 97, 103, 128, 183, 65, 76, 161, 7, 79, 244, 225, 146, 180, 51, 123, 118, 167, 45, 10, 184, 181, 202, 190};
        byte[] vector = {214, 11, 221, 108, 210, 71, 14, 15, 151, 57, 241, 174, 177, 142, 115, 137};

        using (var rijndaelHelper = new RijndaelHelper(key, vector))
        {
            var encrypt = rijndaelHelper.Encrypt("StringToEncrypt");
            var decrypt = rijndaelHelper.Decrypt(encrypt);
            Assert.AreEqual("StringToEncrypt", decrypt);
        }
    }
}

public class RijndaelHelper : IDisposable
{
    Rijndael rijndael;
    UTF8Encoding encoding;

    public RijndaelHelper(byte[] key, byte[] vector)
    {
        encoding = new UTF8Encoding();
        rijndael = Rijndael.Create();
        rijndael.Key = key;
        rijndael.IV = vector;
    }

    public byte[] Encrypt(string valueToEncrypt)
    {
        var bytes = encoding.GetBytes(valueToEncrypt);
        using (var encryptor = rijndael.CreateEncryptor())
        using (var stream = new MemoryStream())
        using (var crypto = new CryptoStream(stream, encryptor, CryptoStreamMode.Write))
        {
            crypto.Write(bytes, 0, bytes.Length);
            crypto.FlushFinalBlock();
            stream.Position = 0;
            var encrypted = new byte[stream.Length];
            stream.Read(encrypted, 0, encrypted.Length);
            return encrypted;
        }
    }

    public string Decrypt(byte[] encryptedValue)
    {
        using (var decryptor = rijndael.CreateDecryptor())
        using (var stream = new MemoryStream())
        using (var crypto = new CryptoStream(stream, decryptor, CryptoStreamMode.Write))
        {
            crypto.Write(encryptedValue, 0, encryptedValue.Length);
            crypto.FlushFinalBlock();
            stream.Position = 0;
            var decryptedBytes = new Byte[stream.Length];
            stream.Read(decryptedBytes, 0, decryptedBytes.Length);
            return encoding.GetString(decryptedBytes);
        }
    }

    public void Dispose()
    {
        if (rijndael != null)
        {
            rijndael.Dispose();
        }
    }
}

我改了这个:

public string ByteArrToString(byte[] byteArr)
{
    byte val;
    string tempStr = "";
    for (int i = 0; i <= byteArr.GetUpperBound(0); i++)
    {
        val = byteArr[i];
        if (val < (byte)10)
            tempStr += "00" + val.ToString();
        else if (val < (byte)100)
            tempStr += "0" + val.ToString();
        else
            tempStr += val.ToString();
    }
    return tempStr;
}

:

    public string ByteArrToString(byte[] byteArr)
    {
        string temp = "";
        foreach (byte b in byteArr)
            temp += b.ToString().PadLeft(3, '0');
        return temp;
    }

加密很简单:正如其他人指出的那样，在System.Security.Cryptography名称空间中有一些类可以为您完成所有工作。使用它们，而不是任何自制的解决方案。

但是解密也很容易。您遇到的问题不是加密算法，而是保护对用于解密的密钥的访问。

我会使用以下解决方案之一:

DPAPI using the ProtectedData class with CurrentUser scope. This is easy as you don't need to worry about a key. Data can only be decrypted by the same user, so no good for sharing data between users or machines. DPAPI using the ProtectedData class with LocalMachine scope. Good for e.g. protecting configuration data on a single secure server. But anyone who can log into the machine can encrypt it, so no good unless the server is secure. Any symmetric algorithm. I typically use the static SymmetricAlgorithm.Create() method if I don't care what algorithm is used (in fact it's Rijndael by default). In this case you need to protect your key somehow. E.g. you can obfuscate it in some way and hide it in your code. But be aware that anyone who is smart enough to decompile your code will likely be able to find the key.

如果你只是想要简单的加密(即，一个坚定的破解者可能会破解，但会锁定大多数普通用户)，只需选择两个长度相等的密码短语，例如:

deoxyribonucleicacid
while (x>0) { x-- };

和xor你的数据与他们(循环密码短语，如果需要)(a)。例如:

1111-2222-3333-4444-5555-6666-7777
deoxyribonucleicaciddeoxyribonucle
while (x>0) { x-- };while (x>0) { 

搜索二进制文件的人很可能认为DNA字符串是一个密钥，但他们不太可能认为C代码是用二进制文件保存的未初始化内存。

(a)请记住，这是非常简单的加密，根据某些定义，可能根本不被认为是加密(因为加密的目的是防止未经授权的访问，而不仅仅是使其更加困难)。当然，即使是最强的加密也不安全因为有人拿着钢管站在钥匙持有人旁边。

正如第一句所述，这是一种让随意的攻击者变得足够困难的方法，他们会继续前进。这类似于防止入室盗窃——你不需要让它变得坚不可摧，你只需要让它比隔壁的房子不那么坚不可摧:-)

我想发布我的解决方案，因为上面的解决方案都不像我的那么简单。让我知道你的想法:

 // This will return an encrypted string based on the unencrypted parameter
 public static string Encrypt(this string DecryptedValue)
 {
      HttpServerUtility.UrlTokenEncode(MachineKey.Protect(Encoding.UTF8.GetBytes(DecryptedValue.Trim())));
 }

 // This will return an unencrypted string based on the parameter
 public static string Decrypt(this string EncryptedValue)
 {
      Encoding.UTF8.GetString(MachineKey.Unprotect(HttpServerUtility.UrlTokenDecode(EncryptedValue)));
 }

可选

这里假设用于加密该值的服务器的MachineKey与用于解密该值的MachineKey相同。如果需要，您可以在Web中指定一个静态MachineKey。配置，使您的应用程序可以解密/加密数据，而不管它在哪里运行(例如开发还是生产服务器)。您可以按照这些说明生成一个静态机器密钥。

这里的其他答案都可以，但AES是一种更安全、最新的加密算法。这是我几年前获得的一个类，用于执行AES加密，随着时间的推移，我已经对其进行了修改，以使其对web应用程序(例如，g)更加友好。我已经构建了加密/解密方法，用于url友好的字符串)。它还有处理字节数组的方法。

注意:你应该在Key(32字节)和Vector(16字节)数组中使用不同的值!您不会希望别人通过假设您按原样使用此代码来找出您的密钥!你所要做的就是改变Key和Vector数组中的一些数字(必须是<= 255)(我在Vector数组中留下了一个无效的值，以确保你这样做…)你可以使用https://www.random.org/bytes/生成一个新的集合:

生成密钥 生成向量

使用它很简单:只需实例化类，然后调用(通常)EncryptToString(string StringToEncrypt)和DecryptString(string StringToDecrypt)作为方法。一旦有了这个类，就不会更容易(或更安全)了。

using System;
using System.Data;
using System.Security.Cryptography;
using System.IO;


public class SimpleAES
{
    // Change these keys
    private byte[] Key = __Replace_Me__({ 123, 217, 19, 11, 24, 26, 85, 45, 114, 184, 27, 162, 37, 112, 222, 209, 241, 24, 175, 144, 173, 53, 196, 29, 24, 26, 17, 218, 131, 236, 53, 209 });

    // a hardcoded IV should not be used for production AES-CBC code
    // IVs should be unpredictable per ciphertext
    private byte[] Vector = __Replace_Me__({ 146, 64, 191, 111, 23, 3, 113, 119, 231, 121, 2521, 112, 79, 32, 114, 156 });


    private ICryptoTransform EncryptorTransform, DecryptorTransform;
    private System.Text.UTF8Encoding UTFEncoder;

    public SimpleAES()
    {
        //This is our encryption method
        RijndaelManaged rm = new RijndaelManaged();

        //Create an encryptor and a decryptor using our encryption method, key, and vector.
        EncryptorTransform = rm.CreateEncryptor(this.Key, this.Vector);
        DecryptorTransform = rm.CreateDecryptor(this.Key, this.Vector);

        //Used to translate bytes to text and vice versa
        UTFEncoder = new System.Text.UTF8Encoding();
    }

    /// -------------- Two Utility Methods (not used but may be useful) -----------
    /// Generates an encryption key.
    static public byte[] GenerateEncryptionKey()
    {
        //Generate a Key.
        RijndaelManaged rm = new RijndaelManaged();
        rm.GenerateKey();
        return rm.Key;
    }

    /// Generates a unique encryption vector
    static public byte[] GenerateEncryptionVector()
    {
        //Generate a Vector
        RijndaelManaged rm = new RijndaelManaged();
        rm.GenerateIV();
        return rm.IV;
    }


    /// ----------- The commonly used methods ------------------------------    
    /// Encrypt some text and return a string suitable for passing in a URL.
    public string EncryptToString(string TextValue)
    {
        return ByteArrToString(Encrypt(TextValue));
    }

    /// Encrypt some text and return an encrypted byte array.
    public byte[] Encrypt(string TextValue)
    {
        //Translates our text value into a byte array.
        Byte[] bytes = UTFEncoder.GetBytes(TextValue);

        //Used to stream the data in and out of the CryptoStream.
        MemoryStream memoryStream = new MemoryStream();

        /*
         * We will have to write the unencrypted bytes to the stream,
         * then read the encrypted result back from the stream.
         */
        #region Write the decrypted value to the encryption stream
        CryptoStream cs = new CryptoStream(memoryStream, EncryptorTransform, CryptoStreamMode.Write);
        cs.Write(bytes, 0, bytes.Length);
        cs.FlushFinalBlock();
        #endregion

        #region Read encrypted value back out of the stream
        memoryStream.Position = 0;
        byte[] encrypted = new byte[memoryStream.Length];
        memoryStream.Read(encrypted, 0, encrypted.Length);
        #endregion

        //Clean up.
        cs.Close();
        memoryStream.Close();

        return encrypted;
    }

    /// The other side: Decryption methods
    public string DecryptString(string EncryptedString)
    {
        return Decrypt(StrToByteArray(EncryptedString));
    }

    /// Decryption when working with byte arrays.    
    public string Decrypt(byte[] EncryptedValue)
    {
        #region Write the encrypted value to the decryption stream
        MemoryStream encryptedStream = new MemoryStream();
        CryptoStream decryptStream = new CryptoStream(encryptedStream, DecryptorTransform, CryptoStreamMode.Write);
        decryptStream.Write(EncryptedValue, 0, EncryptedValue.Length);
        decryptStream.FlushFinalBlock();
        #endregion

        #region Read the decrypted value from the stream.
        encryptedStream.Position = 0;
        Byte[] decryptedBytes = new Byte[encryptedStream.Length];
        encryptedStream.Read(decryptedBytes, 0, decryptedBytes.Length);
        encryptedStream.Close();
        #endregion
        return UTFEncoder.GetString(decryptedBytes);
    }

    /// Convert a string to a byte array.  NOTE: Normally we'd create a Byte Array from a string using an ASCII encoding (like so).
    //      System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding();
    //      return encoding.GetBytes(str);
    // However, this results in character values that cannot be passed in a URL.  So, instead, I just
    // lay out all of the byte values in a long string of numbers (three per - must pad numbers less than 100).
    public byte[] StrToByteArray(string str)
    {
        if (str.Length == 0)
            throw new Exception("Invalid string value in StrToByteArray");

        byte val;
        byte[] byteArr = new byte[str.Length / 3];
        int i = 0;
        int j = 0;
        do
        {
            val = byte.Parse(str.Substring(i, 3));
            byteArr[j++] = val;
            i += 3;
        }
        while (i < str.Length);
        return byteArr;
    }

    // Same comment as above.  Normally the conversion would use an ASCII encoding in the other direction:
    //      System.Text.ASCIIEncoding enc = new System.Text.ASCIIEncoding();
    //      return enc.GetString(byteArr);    
    public string ByteArrToString(byte[] byteArr)
    {
        byte val;
        string tempStr = "";
        for (int i = 0; i <= byteArr.GetUpperBound(0); i++)
        {
            val = byteArr[i];
            if (val < (byte)10)
                tempStr += "00" + val.ToString();
            else if (val < (byte)100)
                tempStr += "0" + val.ToString();
            else
                tempStr += val.ToString();
        }
        return tempStr;
    }
}