在 C# 中加密和解密字符串？[关闭]

下面是使用 RSA 的示例。

重要：使用 RSA 加密可以加密的数据大小是有限制的。例如，256 字节（假设密钥为 2048 位）- 42 字节（最小 OEAP 填充）= 214 字节（最大明文大小）KeySize - MinimumPadding

将 your_rsa_key 替换为您的 RSA 密钥。

var provider = new System.Security.Cryptography.RSACryptoServiceProvider();
provider.ImportParameters(your_rsa_key);

var encryptedBytes = provider.Encrypt(
    System.Text.Encoding.UTF8.GetBytes("Hello World!"), true);

string decryptedTest = System.Text.Encoding.UTF8.GetString(
    provider.Decrypt(encryptedBytes, true));

有关详细信息，请访问 MSDN - RSACryptoServiceProvider

编辑 2013 年 10 月：尽管随着时间的推移，我已经编辑了这个答案以解决缺点，但请参阅 jbtule 的答案以获得更强大、更明智的解决方案。

https://stackoverflow.com/a/10366194/188474

原答案：

下面是从“RijndaelManaged Class”文档和 MCTS 培训工具包派生的工作示例。

编辑 2012 年 4 月：根据 jbtule 的建议，此答案经过编辑以预置 IV，如下所示：

http://msdn.microsoft.com/en-us/library/system.security.cryptography.aesmanaged%28v=vs.95%29.aspx

祝你好运！

public class Crypto
{

    //While an app specific salt is not the best practice for
    //password based encryption, it's probably safe enough as long as
    //it is truly uncommon. Also too much work to alter this answer otherwise.
    private static byte[] _salt = __To_Do__("Add a app specific salt here");

    /// <summary>
    /// Encrypt the given string using AES.  The string can be decrypted using 
    /// DecryptStringAES().  The sharedSecret parameters must match.
    /// </summary>
    /// <param name="plainText">The text to encrypt.</param>
    /// <param name="sharedSecret">A password used to generate a key for encryption.</param>
    public static string EncryptStringAES(string plainText, string sharedSecret)
    {
        if (string.IsNullOrEmpty(plainText))
            throw new ArgumentNullException("plainText");
        if (string.IsNullOrEmpty(sharedSecret))
            throw new ArgumentNullException("sharedSecret");

        string outStr = null;                       // Encrypted string to return
        RijndaelManaged aesAlg = null;              // RijndaelManaged object used to encrypt the data.

        try
        {
            // generate the key from the shared secret and the salt
            Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, _salt);

            // Create a RijndaelManaged object
            aesAlg = new RijndaelManaged();
            aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);

            // Create a decryptor to perform the stream transform.
            ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

            // Create the streams used for encryption.
            using (MemoryStream msEncrypt = new MemoryStream())
            {
                // prepend the IV
                msEncrypt.Write(BitConverter.GetBytes(aesAlg.IV.Length), 0, sizeof(int));
                msEncrypt.Write(aesAlg.IV, 0, aesAlg.IV.Length);
                using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                {
                    using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                    {
                        //Write all data to the stream.
                        swEncrypt.Write(plainText);
                    }
                }
                outStr = Convert.ToBase64String(msEncrypt.ToArray());
            }
        }
        finally
        {
            // Clear the RijndaelManaged object.
            if (aesAlg != null)
                aesAlg.Clear();
        }

        // Return the encrypted bytes from the memory stream.
        return outStr;
    }

    /// <summary>
    /// Decrypt the given string.  Assumes the string was encrypted using 
    /// EncryptStringAES(), using an identical sharedSecret.
    /// </summary>
    /// <param name="cipherText">The text to decrypt.</param>
    /// <param name="sharedSecret">A password used to generate a key for decryption.</param>
    public static string DecryptStringAES(string cipherText, string sharedSecret)
    {
        if (string.IsNullOrEmpty(cipherText))
            throw new ArgumentNullException("cipherText");
        if (string.IsNullOrEmpty(sharedSecret))
            throw new ArgumentNullException("sharedSecret");

        // Declare the RijndaelManaged object
        // used to decrypt the data.
        RijndaelManaged aesAlg = null;

        // Declare the string used to hold
        // the decrypted text.
        string plaintext = null;

        try
        {
            // generate the key from the shared secret and the salt
            Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, _salt);

            // Create the streams used for decryption.                
            byte[] bytes = Convert.FromBase64String(cipherText);
            using (MemoryStream msDecrypt = new MemoryStream(bytes))
            {
                // Create a RijndaelManaged object
                // with the specified key and IV.
                aesAlg = new RijndaelManaged();
                aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);
                // Get the initialization vector from the encrypted stream
                aesAlg.IV = ReadByteArray(msDecrypt);
                // Create a decrytor to perform the stream transform.
                ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
                using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                {
                    using (StreamReader srDecrypt = new StreamReader(csDecrypt))

                        // Read the decrypted bytes from the decrypting stream
                        // and place them in a string.
                        plaintext = srDecrypt.ReadToEnd();
                }
            }
        }
        finally
        {
            // Clear the RijndaelManaged object.
            if (aesAlg != null)
                aesAlg.Clear();
        }

        return plaintext;
    }

    private static byte[] ReadByteArray(Stream s)
    {
        byte[] rawLength = new byte[sizeof(int)];
        if (s.Read(rawLength, 0, rawLength.Length) != rawLength.Length)
        {
            throw new SystemException("Stream did not contain properly formatted byte array");
        }

        byte[] buffer = new byte[BitConverter.ToInt32(rawLength, 0)];
        if (s.Read(buffer, 0, buffer.Length) != buffer.Length)
        {
            throw new SystemException("Did not read byte array properly");
        }

        return buffer;
    }
}

using System;
using System.Data;
using System.Configuration;
using System.Text;
using System.Security.Cryptography;

namespace Encription
{
    class CryptorEngine
    {
        public static string Encrypt(string ToEncrypt, bool useHasing)
        {
            byte[] keyArray;
            byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(ToEncrypt);
            //System.Configuration.AppSettingsReader settingsReader = new     AppSettingsReader();
           string Key = "Bhagwati";
            if (useHasing)
            {
                MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
                keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(Key));
                hashmd5.Clear();  
            }
            else
            {
                keyArray = UTF8Encoding.UTF8.GetBytes(Key);
            }
            TripleDESCryptoServiceProvider tDes = new TripleDESCryptoServiceProvider();
            tDes.Key = keyArray;
            tDes.Mode = CipherMode.ECB;
            tDes.Padding = PaddingMode.PKCS7;
            ICryptoTransform cTransform = tDes.CreateEncryptor();
            byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0,     toEncryptArray.Length);
            tDes.Clear();
            return Convert.ToBase64String(resultArray, 0, resultArray.Length);
        }
        public static string Decrypt(string cypherString, bool useHasing)
        {
            byte[] keyArray;
            byte[] toDecryptArray = Convert.FromBase64String(cypherString);
            //byte[] toEncryptArray = Convert.FromBase64String(cypherString);
            //System.Configuration.AppSettingsReader settingReader = new     AppSettingsReader();
            string key = "Bhagwati";
            if (useHasing)
            {
                MD5CryptoServiceProvider hashmd = new MD5CryptoServiceProvider();
                keyArray = hashmd.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
                hashmd.Clear();
            }
            else
            {
                keyArray = UTF8Encoding.UTF8.GetBytes(key);
            }
            TripleDESCryptoServiceProvider tDes = new TripleDESCryptoServiceProvider();
            tDes.Key = keyArray;
            tDes.Mode = CipherMode.ECB;
            tDes.Padding = PaddingMode.PKCS7;
            ICryptoTransform cTransform = tDes.CreateDecryptor();
            try
            {
                byte[] resultArray = cTransform.TransformFinalBlock(toDecryptArray, 0,         toDecryptArray.Length);

                tDes.Clear();
                return UTF8Encoding.UTF8.GetString(resultArray,0,resultArray.Length);
            }
            catch (Exception ex)
            {
                throw ex;
             }
        }
    }
}

字符串的对称身份验证加密的现代示例。

对称加密的一般最佳做法是使用具有关联数据的经过身份验证的加密 （AEAD），但这不是标准 .net 加密库的一部分。因此，第一个示例使用 AES256，然后使用 HMAC256，即两步加密，然后使用 MAC，这需要更多的开销和更多的密钥。

第二个示例使用更简单的 AES256-GCM 实践，使用开源 Bouncy Castle（通过 nuget）。

这两个示例都有一个 main 函数，该函数采用机密消息字符串、密钥和可选的非机密有效负载，并返回和经过身份验证的加密字符串，可以选择在非机密数据前面添加。理想情况下，您可以将这些密钥与随机生成的 256 位密钥一起使用，请参阅。NewKey()

这两个示例还具有使用字符串密码生成密钥的帮助程序方法。提供这些帮助程序方法是为了方便与其他示例匹配，但它们的安全性要低得多，因为密码的强度将比 256 位密钥弱得多。

更新：添加了重载，由于 StackOverflow 答案限制，只有 Gist 具有 4 个空格缩进和 api 文档的完整格式。byte[]

---

.NET 内置加密 （AES）-Then-MAC（HMAC） [要点]

/*
 * This work (Modern Encryption of a String C#, by James Tuley), 
 * identified by James Tuley, is free of known copyright restrictions.
 * https://gist.github.com/4336842
 * http://creativecommons.org/publicdomain/mark/1.0/ 
 */

using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

namespace Encryption
{
  public static class AESThenHMAC
  {
    private static readonly RandomNumberGenerator Random = RandomNumberGenerator.Create();

    //Preconfigured Encryption Parameters
    public static readonly int BlockBitSize = 128;
    public static readonly int KeyBitSize = 256;

    //Preconfigured Password Key Derivation Parameters
    public static readonly int SaltBitSize = 64;
    public static readonly int Iterations = 10000;
    public static readonly int MinPasswordLength = 12;

    /// <summary>
    /// Helper that generates a random key on each call.
    /// </summary>
    /// <returns></returns>
    public static byte[] NewKey()
    {
      var key = new byte[KeyBitSize / 8];
      Random.GetBytes(key);
      return key;
    }

    /// <summary>
    /// Simple Encryption (AES) then Authentication (HMAC) for a UTF8 Message.
    /// </summary>
    /// <param name="secretMessage">The secret message.</param>
    /// <param name="cryptKey">The crypt key.</param>
    /// <param name="authKey">The auth key.</param>
    /// <param name="nonSecretPayload">(Optional) Non-Secret Payload.</param>
    /// <returns>
    /// Encrypted Message
    /// </returns>
    /// <exception cref="System.ArgumentException">Secret Message Required!;secretMessage</exception>
    /// <remarks>
    /// Adds overhead of (Optional-Payload + BlockSize(16) + Message-Padded-To-Blocksize +  HMac-Tag(32)) * 1.33 Base64
    /// </remarks>
    public static string SimpleEncrypt(string secretMessage, byte[] cryptKey, byte[] authKey,
                       byte[] nonSecretPayload = null)
    {
      if (string.IsNullOrEmpty(secretMessage))
        throw new ArgumentException("Secret Message Required!", "secretMessage");

      var plainText = Encoding.UTF8.GetBytes(secretMessage);
      var cipherText = SimpleEncrypt(plainText, cryptKey, authKey, nonSecretPayload);
      return Convert.ToBase64String(cipherText);
    }

    /// <summary>
    /// Simple Authentication (HMAC) then Decryption (AES) for a secrets UTF8 Message.
    /// </summary>
    /// <param name="encryptedMessage">The encrypted message.</param>
    /// <param name="cryptKey">The crypt key.</param>
    /// <param name="authKey">The auth key.</param>
    /// <param name="nonSecretPayloadLength">Length of the non secret payload.</param>
    /// <returns>
    /// Decrypted Message
    /// </returns>
    /// <exception cref="System.ArgumentException">Encrypted Message Required!;encryptedMessage</exception>
    public static string SimpleDecrypt(string encryptedMessage, byte[] cryptKey, byte[] authKey,
                       int nonSecretPayloadLength = 0)
    {
      if (string.IsNullOrWhiteSpace(encryptedMessage))
        throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");

      var cipherText = Convert.FromBase64String(encryptedMessage);
      var plainText = SimpleDecrypt(cipherText, cryptKey, authKey, nonSecretPayloadLength);
      return plainText == null ? null : Encoding.UTF8.GetString(plainText);
    }

    /// <summary>
    /// Simple Encryption (AES) then Authentication (HMAC) of a UTF8 message
    /// using Keys derived from a Password (PBKDF2).
    /// </summary>
    /// <param name="secretMessage">The secret message.</param>
    /// <param name="password">The password.</param>
    /// <param name="nonSecretPayload">The non secret payload.</param>
    /// <returns>
    /// Encrypted Message
    /// </returns>
    /// <exception cref="System.ArgumentException">password</exception>
    /// <remarks>
    /// Significantly less secure than using random binary keys.
    /// Adds additional non secret payload for key generation parameters.
    /// </remarks>
    public static string SimpleEncryptWithPassword(string secretMessage, string password,
                             byte[] nonSecretPayload = null)
    {
      if (string.IsNullOrEmpty(secretMessage))
        throw new ArgumentException("Secret Message Required!", "secretMessage");

      var plainText = Encoding.UTF8.GetBytes(secretMessage);
      var cipherText = SimpleEncryptWithPassword(plainText, password, nonSecretPayload);
      return Convert.ToBase64String(cipherText);
    }

    /// <summary>
    /// Simple Authentication (HMAC) and then Descryption (AES) of a UTF8 Message
    /// using keys derived from a password (PBKDF2). 
    /// </summary>
    /// <param name="encryptedMessage">The encrypted message.</param>
    /// <param name="password">The password.</param>
    /// <param name="nonSecretPayloadLength">Length of the non secret payload.</param>
    /// <returns>
    /// Decrypted Message
    /// </returns>
    /// <exception cref="System.ArgumentException">Encrypted Message Required!;encryptedMessage</exception>
    /// <remarks>
    /// Significantly less secure than using random binary keys.
    /// </remarks>
    public static string SimpleDecryptWithPassword(string encryptedMessage, string password,
                             int nonSecretPayloadLength = 0)
    {
      if (string.IsNullOrWhiteSpace(encryptedMessage))
        throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");

      var cipherText = Convert.FromBase64String(encryptedMessage);
      var plainText = SimpleDecryptWithPassword(cipherText, password, nonSecretPayloadLength);
      return plainText == null ? null : Encoding.UTF8.GetString(plainText);
    }

    public static byte[] SimpleEncrypt(byte[] secretMessage, byte[] cryptKey, byte[] authKey, byte[] nonSecretPayload = null)
    {
      //User Error Checks
      if (cryptKey == null || cryptKey.Length != KeyBitSize / 8)
        throw new ArgumentException(String.Format("Key needs to be {0} bit!", KeyBitSize), "cryptKey");

      if (authKey == null || authKey.Length != KeyBitSize / 8)
        throw new ArgumentException(String.Format("Key needs to be {0} bit!", KeyBitSize), "authKey");

      if (secretMessage == null || secretMessage.Length < 1)
        throw new ArgumentException("Secret Message Required!", "secretMessage");

      //non-secret payload optional
      nonSecretPayload = nonSecretPayload ?? new byte[] { };

      byte[] cipherText;
      byte[] iv;

      using (var aes = new AesManaged
      {
        KeySize = KeyBitSize,
        BlockSize = BlockBitSize,
        Mode = CipherMode.CBC,
        Padding = PaddingMode.PKCS7
      })
      {

        //Use random IV
        aes.GenerateIV();
        iv = aes.IV;

        using (var encrypter = aes.CreateEncryptor(cryptKey, iv))
        using (var cipherStream = new MemoryStream())
        {
          using (var cryptoStream = new CryptoStream(cipherStream, encrypter, CryptoStreamMode.Write))
          using (var binaryWriter = new BinaryWriter(cryptoStream))
          {
            //Encrypt Data
            binaryWriter.Write(secretMessage);
          }

          cipherText = cipherStream.ToArray();
        }

      }

      //Assemble encrypted message and add authentication
      using (var hmac = new HMACSHA256(authKey))
      using (var encryptedStream = new MemoryStream())
      {
        using (var binaryWriter = new BinaryWriter(encryptedStream))
        {
          //Prepend non-secret payload if any
          binaryWriter.Write(nonSecretPayload);
          //Prepend IV
          binaryWriter.Write(iv);
          //Write Ciphertext
          binaryWriter.Write(cipherText);
          binaryWriter.Flush();

          //Authenticate all data
          var tag = hmac.ComputeHash(encryptedStream.ToArray());
          //Postpend tag
          binaryWriter.Write(tag);
        }
        return encryptedStream.ToArray();
      }

    }

    public static byte[] SimpleDecrypt(byte[] encryptedMessage, byte[] cryptKey, byte[] authKey, int nonSecretPayloadLength = 0)
    {

      //Basic Usage Error Checks
      if (cryptKey == null || cryptKey.Length != KeyBitSize / 8)
        throw new ArgumentException(String.Format("CryptKey needs to be {0} bit!", KeyBitSize), "cryptKey");

      if (authKey == null || authKey.Length != KeyBitSize / 8)
        throw new ArgumentException(String.Format("AuthKey needs to be {0} bit!", KeyBitSize), "authKey");

      if (encryptedMessage == null || encryptedMessage.Length == 0)
        throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");

      using (var hmac = new HMACSHA256(authKey))
      {
        var sentTag = new byte[hmac.HashSize / 8];
        //Calculate Tag
        var calcTag = hmac.ComputeHash(encryptedMessage, 0, encryptedMessage.Length - sentTag.Length);
        var ivLength = (BlockBitSize / 8);

        //if message length is to small just return null
        if (encryptedMessage.Length < sentTag.Length + nonSecretPayloadLength + ivLength)
          return null;

        //Grab Sent Tag
        Array.Copy(encryptedMessage, encryptedMessage.Length - sentTag.Length, sentTag, 0, sentTag.Length);

        //Compare Tag with constant time comparison
        var compare = 0;
        for (var i = 0; i < sentTag.Length; i++)
          compare |= sentTag[i] ^ calcTag[i]; 

        //if message doesn't authenticate return null
        if (compare != 0)
          return null;

        using (var aes = new AesManaged
        {
          KeySize = KeyBitSize,
          BlockSize = BlockBitSize,
          Mode = CipherMode.CBC,
          Padding = PaddingMode.PKCS7
        })
        {

          //Grab IV from message
          var iv = new byte[ivLength];
          Array.Copy(encryptedMessage, nonSecretPayloadLength, iv, 0, iv.Length);

          using (var decrypter = aes.CreateDecryptor(cryptKey, iv))
          using (var plainTextStream = new MemoryStream())
          {
            using (var decrypterStream = new CryptoStream(plainTextStream, decrypter, CryptoStreamMode.Write))
            using (var binaryWriter = new BinaryWriter(decrypterStream))
            {
              //Decrypt Cipher Text from Message
              binaryWriter.Write(
                encryptedMessage,
                nonSecretPayloadLength + iv.Length,
                encryptedMessage.Length - nonSecretPayloadLength - iv.Length - sentTag.Length
              );
            }
            //Return Plain Text
            return plainTextStream.ToArray();
          }
        }
      }
    }

    public static byte[] SimpleEncryptWithPassword(byte[] secretMessage, string password, byte[] nonSecretPayload = null)
    {
      nonSecretPayload = nonSecretPayload ?? new byte[] {};

      //User Error Checks
      if (string.IsNullOrWhiteSpace(password) || password.Length < MinPasswordLength)
        throw new ArgumentException(String.Format("Must have a password of at least {0} characters!", MinPasswordLength), "password");

      if (secretMessage == null || secretMessage.Length ==0)
        throw new ArgumentException("Secret Message Required!", "secretMessage");

      var payload = new byte[((SaltBitSize / 8) * 2) + nonSecretPayload.Length];

      Array.Copy(nonSecretPayload, payload, nonSecretPayload.Length);
      int payloadIndex = nonSecretPayload.Length;

      byte[] cryptKey;
      byte[] authKey;
      //Use Random Salt to prevent pre-generated weak password attacks.
      using (var generator = new Rfc2898DeriveBytes(password, SaltBitSize / 8, Iterations))
      {
        var salt = generator.Salt;

        //Generate Keys
        cryptKey = generator.GetBytes(KeyBitSize / 8);

        //Create Non Secret Payload
        Array.Copy(salt, 0, payload, payloadIndex, salt.Length);
        payloadIndex += salt.Length;
      }

      //Deriving separate key, might be less efficient than using HKDF, 
      //but now compatible with RNEncryptor which had a very similar wireformat and requires less code than HKDF.
      using (var generator = new Rfc2898DeriveBytes(password, SaltBitSize / 8, Iterations))
      {
        var salt = generator.Salt;

        //Generate Keys
        authKey = generator.GetBytes(KeyBitSize / 8);

        //Create Rest of Non Secret Payload
        Array.Copy(salt, 0, payload, payloadIndex, salt.Length);
      }

      return SimpleEncrypt(secretMessage, cryptKey, authKey, payload);
    }

    public static byte[] SimpleDecryptWithPassword(byte[] encryptedMessage, string password, int nonSecretPayloadLength = 0)
    {
      //User Error Checks
      if (string.IsNullOrWhiteSpace(password) || password.Length < MinPasswordLength)
        throw new ArgumentException(String.Format("Must have a password of at least {0} characters!", MinPasswordLength), "password");

      if (encryptedMessage == null || encryptedMessage.Length == 0)
        throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");

      var cryptSalt = new byte[SaltBitSize / 8];
      var authSalt = new byte[SaltBitSize / 8];

      //Grab Salt from Non-Secret Payload
      Array.Copy(encryptedMessage, nonSecretPayloadLength, cryptSalt, 0, cryptSalt.Length);
      Array.Copy(encryptedMessage, nonSecretPayloadLength + cryptSalt.Length, authSalt, 0, authSalt.Length);

      byte[] cryptKey;
      byte[] authKey;

      //Generate crypt key
      using (var generator = new Rfc2898DeriveBytes(password, cryptSalt, Iterations))
      {
        cryptKey = generator.GetBytes(KeyBitSize / 8);
      }
      //Generate auth key
      using (var generator = new Rfc2898DeriveBytes(password, authSalt, Iterations))
      {
        authKey = generator.GetBytes(KeyBitSize / 8);
      }

      return SimpleDecrypt(encryptedMessage, cryptKey, authKey, cryptSalt.Length + authSalt.Length + nonSecretPayloadLength);
    }
  }
}

---

充气城堡 AES-GCM [要点]

/*
 * This work (Modern Encryption of a String C#, by James Tuley), 
 * identified by James Tuley, is free of known copyright restrictions.
 * https://gist.github.com/4336842
 * http://creativecommons.org/publicdomain/mark/1.0/ 
 */

using System;
using System.IO;
using System.Text;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Engines;
using Org.BouncyCastle.Crypto.Generators;
using Org.BouncyCastle.Crypto.Modes;
using Org.BouncyCastle.Crypto.Parameters;
using Org.BouncyCastle.Security;
namespace Encryption
{

  public static class AESGCM
  {
    private static readonly SecureRandom Random = new SecureRandom();

    //Preconfigured Encryption Parameters
    public static readonly int NonceBitSize = 128;
    public static readonly int MacBitSize = 128;
    public static readonly int KeyBitSize = 256;

    //Preconfigured Password Key Derivation Parameters
    public static readonly int SaltBitSize = 128;
    public static readonly int Iterations = 10000;
    public static readonly int MinPasswordLength = 12;


    /// <summary>
    /// Helper that generates a random new key on each call.
    /// </summary>
    /// <returns></returns>
    public static byte[] NewKey()
    {
      var key = new byte[KeyBitSize / 8];
      Random.NextBytes(key);
      return key;
    }

    /// <summary>
    /// Simple Encryption And Authentication (AES-GCM) of a UTF8 string.
    /// </summary>
    /// <param name="secretMessage">The secret message.</param>
    /// <param name="key">The key.</param>
    /// <param name="nonSecretPayload">Optional non-secret payload.</param>
    /// <returns>
    /// Encrypted Message
    /// </returns>
    /// <exception cref="System.ArgumentException">Secret Message Required!;secretMessage</exception>
    /// <remarks>
    /// Adds overhead of (Optional-Payload + BlockSize(16) + Message +  HMac-Tag(16)) * 1.33 Base64
    /// </remarks>
    public static string SimpleEncrypt(string secretMessage, byte[] key, byte[] nonSecretPayload = null)
    {
      if (string.IsNullOrEmpty(secretMessage))
        throw new ArgumentException("Secret Message Required!", "secretMessage");

      var plainText = Encoding.UTF8.GetBytes(secretMessage);
      var cipherText = SimpleEncrypt(plainText, key, nonSecretPayload);
      return Convert.ToBase64String(cipherText);
    }


    /// <summary>
    /// Simple Decryption & Authentication (AES-GCM) of a UTF8 Message
    /// </summary>
    /// <param name="encryptedMessage">The encrypted message.</param>
    /// <param name="key">The key.</param>
    /// <param name="nonSecretPayloadLength">Length of the optional non-secret payload.</param>
    /// <returns>Decrypted Message</returns>
    public static string SimpleDecrypt(string encryptedMessage, byte[] key, int nonSecretPayloadLength = 0)
    {
      if (string.IsNullOrEmpty(encryptedMessage))
        throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");

      var cipherText = Convert.FromBase64String(encryptedMessage);
      var plainText = SimpleDecrypt(cipherText, key, nonSecretPayloadLength);
      return plainText == null ? null : Encoding.UTF8.GetString(plainText);
    }

    /// <summary>
    /// Simple Encryption And Authentication (AES-GCM) of a UTF8 String
    /// using key derived from a password (PBKDF2).
    /// </summary>
    /// <param name="secretMessage">The secret message.</param>
    /// <param name="password">The password.</param>
    /// <param name="nonSecretPayload">The non secret payload.</param>
    /// <returns>
    /// Encrypted Message
    /// </returns>
    /// <remarks>
    /// Significantly less secure than using random binary keys.
    /// Adds additional non secret payload for key generation parameters.
    /// </remarks>
    public static string SimpleEncryptWithPassword(string secretMessage, string password,
                             byte[] nonSecretPayload = null)
    {
      if (string.IsNullOrEmpty(secretMessage))
        throw new ArgumentException("Secret Message Required!", "secretMessage");

      var plainText = Encoding.UTF8.GetBytes(secretMessage);
      var cipherText = SimpleEncryptWithPassword(plainText, password, nonSecretPayload);
      return Convert.ToBase64String(cipherText);
    }


    /// <summary>
    /// Simple Decryption and Authentication (AES-GCM) of a UTF8 message
    /// using a key derived from a password (PBKDF2)
    /// </summary>
    /// <param name="encryptedMessage">The encrypted message.</param>
    /// <param name="password">The password.</param>
    /// <param name="nonSecretPayloadLength">Length of the non secret payload.</param>
    /// <returns>
    /// Decrypted Message
    /// </returns>
    /// <exception cref="System.ArgumentException">Encrypted Message Required!;encryptedMessage</exception>
    /// <remarks>
    /// Significantly less secure than using random binary keys.
    /// </remarks>
    public static string SimpleDecryptWithPassword(string encryptedMessage, string password,
                             int nonSecretPayloadLength = 0)
    {
      if (string.IsNullOrWhiteSpace(encryptedMessage))
        throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");

      var cipherText = Convert.FromBase64String(encryptedMessage);
      var plainText = SimpleDecryptWithPassword(cipherText, password, nonSecretPayloadLength);
      return plainText == null ? null : Encoding.UTF8.GetString(plainText);
    }

    public static byte[] SimpleEncrypt(byte[] secretMessage, byte[] key, byte[] nonSecretPayload = null)
    {
      //User Error Checks
      if (key == null || key.Length != KeyBitSize / 8)
        throw new ArgumentException(String.Format("Key needs to be {0} bit!", KeyBitSize), "key");

      if (secretMessage == null || secretMessage.Length == 0)
        throw new ArgumentException("Secret Message Required!", "secretMessage");

      //Non-secret Payload Optional
      nonSecretPayload = nonSecretPayload ?? new byte[] { };

      //Using random nonce large enough not to repeat
      var nonce = new byte[NonceBitSize / 8];
      Random.NextBytes(nonce, 0, nonce.Length);

      var cipher = new GcmBlockCipher(new AesFastEngine());
      var parameters = new AeadParameters(new KeyParameter(key), MacBitSize, nonce, nonSecretPayload);
      cipher.Init(true, parameters);

      //Generate Cipher Text With Auth Tag
      var cipherText = new byte[cipher.GetOutputSize(secretMessage.Length)];
      var len = cipher.ProcessBytes(secretMessage, 0, secretMessage.Length, cipherText, 0);
      cipher.DoFinal(cipherText, len);

      //Assemble Message
      using (var combinedStream = new MemoryStream())
      {
        using (var binaryWriter = new BinaryWriter(combinedStream))
        {
          //Prepend Authenticated Payload
          binaryWriter.Write(nonSecretPayload);
          //Prepend Nonce
          binaryWriter.Write(nonce);
          //Write Cipher Text
          binaryWriter.Write(cipherText);
        }
        return combinedStream.ToArray();
      }
    }

    public static byte[] SimpleDecrypt(byte[] encryptedMessage, byte[] key, int nonSecretPayloadLength = 0)
    {
      //User Error Checks
      if (key == null || key.Length != KeyBitSize / 8)
        throw new ArgumentException(String.Format("Key needs to be {0} bit!", KeyBitSize), "key");

      if (encryptedMessage == null || encryptedMessage.Length == 0)
        throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");

      using (var cipherStream = new MemoryStream(encryptedMessage))
      using (var cipherReader = new BinaryReader(cipherStream))
      {
        //Grab Payload
        var nonSecretPayload = cipherReader.ReadBytes(nonSecretPayloadLength);

        //Grab Nonce
        var nonce = cipherReader.ReadBytes(NonceBitSize / 8);

        var cipher = new GcmBlockCipher(new AesFastEngine());
        var parameters = new AeadParameters(new KeyParameter(key), MacBitSize, nonce, nonSecretPayload);
        cipher.Init(false, parameters);

        //Decrypt Cipher Text
        var cipherText = cipherReader.ReadBytes(encryptedMessage.Length - nonSecretPayloadLength - nonce.Length);
        var plainText = new byte[cipher.GetOutputSize(cipherText.Length)];  

        try
        {
          var len = cipher.ProcessBytes(cipherText, 0, cipherText.Length, plainText, 0);
          cipher.DoFinal(plainText, len);

        }
        catch (InvalidCipherTextException)
        {
          //Return null if it doesn't authenticate
          return null;
        }

        return plainText;
      }

    }

    public static byte[] SimpleEncryptWithPassword(byte[] secretMessage, string password, byte[] nonSecretPayload = null)
    {
      nonSecretPayload = nonSecretPayload ?? new byte[] {};

      //User Error Checks
      if (string.IsNullOrWhiteSpace(password) || password.Length < MinPasswordLength)
        throw new ArgumentException(String.Format("Must have a password of at least {0} characters!", MinPasswordLength), "password");

      if (secretMessage == null || secretMessage.Length == 0)
        throw new ArgumentException("Secret Message Required!", "secretMessage");

      var generator = new Pkcs5S2ParametersGenerator();

      //Use Random Salt to minimize pre-generated weak password attacks.
      var salt = new byte[SaltBitSize / 8];
      Random.NextBytes(salt);

      generator.Init(
        PbeParametersGenerator.Pkcs5PasswordToBytes(password.ToCharArray()),
        salt,
        Iterations);

      //Generate Key
      var key = (KeyParameter)generator.GenerateDerivedMacParameters(KeyBitSize);

      //Create Full Non Secret Payload
      var payload = new byte[salt.Length + nonSecretPayload.Length];
      Array.Copy(nonSecretPayload, payload, nonSecretPayload.Length);
      Array.Copy(salt,0, payload,nonSecretPayload.Length, salt.Length);

      return SimpleEncrypt(secretMessage, key.GetKey(), payload);
    }

    public static byte[] SimpleDecryptWithPassword(byte[] encryptedMessage, string password, int nonSecretPayloadLength = 0)
    {
      //User Error Checks
      if (string.IsNullOrWhiteSpace(password) || password.Length < MinPasswordLength)
        throw new ArgumentException(String.Format("Must have a password of at least {0} characters!", MinPasswordLength), "password");

      if (encryptedMessage == null || encryptedMessage.Length == 0)
        throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");

      var generator = new Pkcs5S2ParametersGenerator();

      //Grab Salt from Payload
      var salt = new byte[SaltBitSize / 8];
      Array.Copy(encryptedMessage, nonSecretPayloadLength, salt, 0, salt.Length);

      generator.Init(
        PbeParametersGenerator.Pkcs5PasswordToBytes(password.ToCharArray()),
        salt,
        Iterations);

      //Generate Key
      var key = (KeyParameter)generator.GenerateDerivedMacParameters(KeyBitSize);

      return SimpleDecrypt(encryptedMessage, key.GetKey(), salt.Length + nonSecretPayloadLength);
    }
  }
}

我想给你我的贡献，我的 AES 代码（这里是文档）algorhytm，用 C# （.NET Framework 4） 编写，也完全适用于有限的平台，如 .NET Compact Framework for Windows Phone 7.0+（并非所有平台都支持 .NET Framework 的所有 criptographic 方法！Rfc2898DeriveBytes

我希望这可以帮助任何人！

using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

public static class Crypto
{
    private static readonly byte[] IVa = new byte[] { 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x11, 0x11, 0x12, 0x13, 0x14, 0x0e, 0x16, 0x17 };


    public static string Encrypt(this string text, string salt)
    {
        try
        {
            using (Aes aes = new AesManaged())
            {
                Rfc2898DeriveBytes deriveBytes = new Rfc2898DeriveBytes(Encoding.UTF8.GetString(IVa, 0, IVa.Length), Encoding.UTF8.GetBytes(salt));
                aes.Key = deriveBytes.GetBytes(128 / 8);
                aes.IV = aes.Key;
                using (MemoryStream encryptionStream = new MemoryStream())
                {
                    using (CryptoStream encrypt = new CryptoStream(encryptionStream, aes.CreateEncryptor(), CryptoStreamMode.Write))
                    {
                        byte[] cleanText = Encoding.UTF8.GetBytes(text);
                        encrypt.Write(cleanText, 0, cleanText.Length);
                        encrypt.FlushFinalBlock();
                    }

                    byte[] encryptedData = encryptionStream.ToArray();
                    string encryptedText = Convert.ToBase64String(encryptedData);


                    return encryptedText;
                }
            }
        }
        catch
        {
            return String.Empty;
        }
    }

    public static string Decrypt(this string text, string salt)
    {
        try
        {
            using (Aes aes = new AesManaged())
            {
                Rfc2898DeriveBytes deriveBytes = new Rfc2898DeriveBytes(Encoding.UTF8.GetString(IVa, 0, IVa.Length), Encoding.UTF8.GetBytes(salt));
                aes.Key = deriveBytes.GetBytes(128 / 8);
                aes.IV = aes.Key;

                using (MemoryStream decryptionStream = new MemoryStream())
                {
                    using (CryptoStream decrypt = new CryptoStream(decryptionStream, aes.CreateDecryptor(), CryptoStreamMode.Write))
                    {
                        byte[] encryptedData = Convert.FromBase64String(text);


                        decrypt.Write(encryptedData, 0, encryptedData.Length);
                        decrypt.Flush();
                    }

                    byte[] decryptedData = decryptionStream.ToArray();
                    string decryptedText = Encoding.UTF8.GetString(decryptedData, 0, decryptedData.Length);


                    return decryptedText;
                }
            }
        }
        catch
        {
            return String.Empty;
        }
        }
    }
}

BouncyCastle 是一个很棒的 .NET 加密库，它以 Nuget 包的形式提供，可安装到您的项目中。我更喜欢它，而不是 System.Security.Cryptography 库中当前可用的内容。它在可用算法方面为您提供了更多选择，并为这些算法提供了更多模式。

这是 TwoFish 实现的一个示例，它由 Bruce Schneier（我们所有偏执狂的英雄）编写。这是一种像 Rijndael 一样的对称算法 （又名 AES）。它是AES标准的三个决赛入围者之一，也是布鲁斯·施奈尔（Bruce Schneier）编写的另一种著名算法BlowFish的兄弟姐妹。

bouncycastle 的第一件事是创建一个加密器类，这将使在库中实现其他分组密码变得更加容易。以下加密器类采用泛型参数 T，其中 T 实现 IBlockCipher 并具有默认构造函数。

更新：由于大众的需求，我决定实现生成随机 IV 并将 HMAC 包含在此类中。虽然从风格的角度来看，这违背了单一责任的 SOLID 原则，但由于这个类的性质，我放弃了。这个类现在将采用两个泛型参数，一个用于密码，一个用于摘要。它使用 RNGCryptoServiceProvider 自动生成 IV 以提供良好的 RNG 熵，并允许您使用 BouncyCastle 中所需的任何摘要算法来生成 MAC。

using System;
using System.Security.Cryptography;
using System.Text;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Macs;
using Org.BouncyCastle.Crypto.Modes;
using Org.BouncyCastle.Crypto.Paddings;
using Org.BouncyCastle.Crypto.Parameters;

public sealed class Encryptor<TBlockCipher, TDigest>
    where TBlockCipher : IBlockCipher, new()
    where TDigest : IDigest, new()
{
    private Encoding encoding;

    private IBlockCipher blockCipher;

    private BufferedBlockCipher cipher;

    private HMac mac;

    private byte[] key;

    public Encryptor(Encoding encoding, byte[] key, byte[] macKey)
    {
        this.encoding = encoding;
        this.key = key;
        this.Init(key, macKey, new Pkcs7Padding());
    }

    public Encryptor(Encoding encoding, byte[] key, byte[] macKey, IBlockCipherPadding padding)
    {
        this.encoding = encoding;
        this.key = key;
        this.Init(key, macKey, padding);
    }

    private void Init(byte[] key, byte[] macKey, IBlockCipherPadding padding)
    {
        this.blockCipher = new CbcBlockCipher(new TBlockCipher());
        this.cipher = new PaddedBufferedBlockCipher(this.blockCipher, padding);
        this.mac = new HMac(new TDigest());
        this.mac.Init(new KeyParameter(macKey));
    }

    public string Encrypt(string plain)
    {
        return Convert.ToBase64String(EncryptBytes(plain));
    }

    public byte[] EncryptBytes(string plain)
    {
        byte[] input = this.encoding.GetBytes(plain);

        var iv = this.GenerateIV();

        var cipher = this.BouncyCastleCrypto(true, input, new ParametersWithIV(new KeyParameter(key), iv));
        byte[] message = CombineArrays(iv, cipher);

        this.mac.Reset();
        this.mac.BlockUpdate(message, 0, message.Length);
        byte[] digest = new byte[this.mac.GetUnderlyingDigest().GetDigestSize()];
        this.mac.DoFinal(digest, 0);

        var result = CombineArrays(digest, message);
        return result;
    }

    public byte[] DecryptBytes(byte[] bytes)
    {
        // split the digest into component parts
        var digest = new byte[this.mac.GetUnderlyingDigest().GetDigestSize()];
        var message = new byte[bytes.Length - digest.Length];
        var iv = new byte[this.blockCipher.GetBlockSize()];
        var cipher = new byte[message.Length - iv.Length];

        Buffer.BlockCopy(bytes, 0, digest, 0, digest.Length);
        Buffer.BlockCopy(bytes, digest.Length, message, 0, message.Length);
        if (!IsValidHMac(digest, message))
        {
            throw new CryptoException();
        }

        Buffer.BlockCopy(message, 0, iv, 0, iv.Length);
        Buffer.BlockCopy(message, iv.Length, cipher, 0, cipher.Length);

        byte[] result = this.BouncyCastleCrypto(false, cipher, new ParametersWithIV(new KeyParameter(key), iv));
        return result;
    }

    public string Decrypt(byte[] bytes)
    {
        return this.encoding.GetString(DecryptBytes(bytes));
    }

    public string Decrypt(string cipher)
    {
        return this.Decrypt(Convert.FromBase64String(cipher));
    }

    private bool IsValidHMac(byte[] digest, byte[] message)
    {
        this.mac.Reset();
        this.mac.BlockUpdate(message, 0, message.Length);
        byte[] computed = new byte[this.mac.GetUnderlyingDigest().GetDigestSize()];
        this.mac.DoFinal(computed, 0);

        return AreEqual(digest,computed);
    }

    private static bool AreEqual(byte [] digest, byte[] computed)
    {
        if(digest.Length != computed.Length)
        {
            return false;
        }

        int result = 0;
        for (int i = 0; i < digest.Length; i++)
        {
            // compute equality of all bytes before returning.
            //   helps prevent timing attacks: 
            //   https://codahale.com/a-lesson-in-timing-attacks/
            result |= digest[i] ^ computed[i];
        }

        return result == 0;
    }

    private byte[] BouncyCastleCrypto(bool forEncrypt, byte[] input, ICipherParameters parameters)
    {
        try
        {
            cipher.Init(forEncrypt, parameters);

            return this.cipher.DoFinal(input);
        }
        catch (CryptoException)
        {
            throw;
        }
    }

    private byte[] GenerateIV()
    {
        using (var provider = new RNGCryptoServiceProvider())
        {
            // 1st block
            byte[] result = new byte[this.blockCipher.GetBlockSize()];
            provider.GetBytes(result);

            return result;
        }
    }

    private static byte[] CombineArrays(byte[] source1, byte[] source2)
    {
        byte[] result = new byte[source1.Length + source2.Length];
        Buffer.BlockCopy(source1, 0, result, 0, source1.Length);
        Buffer.BlockCopy(source2, 0, result, source1.Length, source2.Length);

        return result;
    }
}

接下来，只需在新类上调用 encrypt 和 decrypt 方法，下面是使用 twofish 的示例：

var encrypt = new Encryptor<TwofishEngine, Sha1Digest>(Encoding.UTF8, key, hmacKey);

string cipher = encrypt.Encrypt("TEST");   
string plainText = encrypt.Decrypt(cipher);

替换另一个分组密码（如 TripleDES）同样容易：

var des = new Encryptor<DesEdeEngine, Sha1Digest>(Encoding.UTF8, key, hmacKey);

string cipher = des.Encrypt("TEST");
string plainText = des.Decrypt(cipher);

最后，如果要将AES与SHA256 HMAC一起使用，可以执行以下操作：

var aes = new Encryptor<AesEngine, Sha256Digest>(Encoding.UTF8, key, hmacKey);

cipher = aes.Encrypt("TEST");
plainText = aes.Decrypt(cipher);

加密最难的部分实际上涉及密钥而不是算法。您必须考虑将密钥存储在哪里，如果必须，如何交换它们。这些算法都经受住了时间的考验，而且极难破解。想要从您那里窃取信息的人不会花费永恒的时间对您的消息进行密码分析，他们会试图弄清楚您的密钥是什么或在哪里。因此，#1 明智地选择您的密钥，#2 将它们存储在安全的地方，如果您使用 web.config 和 IIS，则可以加密 web.config 的一部分，最后，如果您必须交换密钥，请确保交换密钥的协议是安全的。

更新 2更改了比较方法以缓解定时攻击。在此处查看更多信息 http://codahale.com/a-lesson-in-timing-attacks/ .还更新为默认为 PKCS7 填充，并添加了新的构造函数，以允许最终用户选择他们想要使用的填充。感谢@CodesInChaos的建议。

如果您使用的是 ASP.Net 现在可以使用 .Net 4.0 及更高版本中的内置功能。

System.Web.Security.MachineKey

.Net 4.5 具有 和 .MachineKey.Protect()MachineKey.Unprotect()

.Net 4.0 具有 和 .您只需将 MachineKeyProtection 设置为“All”。MachineKey.Encode()MachineKey.Decode()

除此之外 ASP.Net 此类似乎会在每次应用程序重新启动时生成一个新密钥，因此不起作用。快速浏览一下 ILSpy，在我看来，如果缺少适当的 app.settings，它会生成自己的默认值。因此，您实际上可以在 ASP.Net 之外设置它。

我无法在 System.Web 命名空间之外找到等效 non-ASP.Net。

这是 Brett 放在这里的类。但是，我做了一些轻微的编辑，因为在将其用于 URL 字符串进行加密和解密时，我收到错误“Base-64 char 数组的长度无效”。

public class CryptoURL
{
    private static byte[] _salt = Encoding.ASCII.GetBytes("Catto_Salt_Enter_Any_Value99");

    /// <summary>
    /// Encrypt the given string using AES.  The string can be decrypted using 
    /// DecryptStringAES().  The sharedSecret parameters must match. 
    /// The SharedSecret for the Password Reset that is used is in the next line
    ///  string sharedSecret = "OneUpSharedSecret9";
    /// </summary>
    /// <param name="plainText">The text to encrypt.</param>
    /// <param name="sharedSecret">A password used to generate a key for encryption.</param>
    public static string EncryptString(string plainText, string sharedSecret)
    {
        if (string.IsNullOrEmpty(plainText))
            throw new ArgumentNullException("plainText");
        if (string.IsNullOrEmpty(sharedSecret))
            throw new ArgumentNullException("sharedSecret");

        string outStr = null;                       // Encrypted string to return
        RijndaelManaged aesAlg = null;              // RijndaelManaged object used to encrypt the data.

        try
        {
            // generate the key from the shared secret and the salt
            Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, _salt);

            // Create a RijndaelManaged object
            aesAlg = new RijndaelManaged();
            aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);

            // Create a decryptor to perform the stream transform.
            ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

            // Create the streams used for encryption.
            using (MemoryStream msEncrypt = new MemoryStream())
            {
                // prepend the IV
                msEncrypt.Write(BitConverter.GetBytes(aesAlg.IV.Length), 0, sizeof(int));
                msEncrypt.Write(aesAlg.IV, 0, aesAlg.IV.Length);
                using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                {
                    using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                    {
                        //Write all data to the stream.
                        swEncrypt.Write(plainText);
                    }
                }

                outStr = HttpServerUtility.UrlTokenEncode(msEncrypt.ToArray());
                //outStr = Convert.ToBase64String(msEncrypt.ToArray());
                // you may need to add a reference. right click reference in solution explorer => "add Reference" => .NET tab => select "System.Web"
            }
        }
        finally
        {
            // Clear the RijndaelManaged object.
            if (aesAlg != null)
                aesAlg.Clear();
        }

        // Return the encrypted bytes from the memory stream.
        return outStr;
    }

    /// <summary>
    /// Decrypt the given string.  Assumes the string was encrypted using 
    /// EncryptStringAES(), using an identical sharedSecret.
    /// </summary>
    /// <param name="cipherText">The text to decrypt.</param>
    /// <param name="sharedSecret">A password used to generate a key for decryption.</param>
    public static string DecryptString(string cipherText, string sharedSecret)
    {
        if (string.IsNullOrEmpty(cipherText))
            throw new ArgumentNullException("cipherText");
        if (string.IsNullOrEmpty(sharedSecret))
            throw new ArgumentNullException("sharedSecret");

        // Declare the RijndaelManaged object
        // used to decrypt the data.
        RijndaelManaged aesAlg = null;

        // Declare the string used to hold
        // the decrypted text.
        string plaintext = null;

        byte[] inputByteArray;

        try
        {
            // generate the key from the shared secret and the salt
            Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, _salt);

            // Create the streams used for decryption.                
            //byte[] bytes = Convert.FromBase64String(cipherText);
            inputByteArray = HttpServerUtility.UrlTokenDecode(cipherText);

            using (MemoryStream msDecrypt = new MemoryStream(inputByteArray))
            {
                // Create a RijndaelManaged object
                // with the specified key and IV.
                aesAlg = new RijndaelManaged();
                aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);
                // Get the initialization vector from the encrypted stream
                aesAlg.IV = ReadByteArray(msDecrypt);
                // Create a decrytor to perform the stream transform.
                ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
                using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                {
                    using (StreamReader srDecrypt = new StreamReader(csDecrypt))

                        // Read the decrypted bytes from the decrypting stream
                        // and place them in a string.
                        plaintext = srDecrypt.ReadToEnd();
                }
            }
        }
        catch (System.Exception ex)
        {
            return "ERROR";
            //throw ex;

        }
        finally
        {
            // Clear the RijndaelManaged object.
            if (aesAlg != null)
                aesAlg.Clear();
        }

        return plaintext;
    }

    static string ConvertStringArrayToString(string[] array)
    {
        //
        // Concatenate all the elements into a StringBuilder.
        //
        StringBuilder builder = new StringBuilder();
        foreach (string value in array)
        {
            builder.Append(value);
            builder.Append('.');
        }
        return builder.ToString();
    }

    private static byte[] ReadByteArray(Stream s)
    {
        byte[] rawLength = new byte[sizeof(int)];
        if (s.Read(rawLength, 0, rawLength.Length) != rawLength.Length)
        {
            throw new SystemException("Stream did not contain properly formatted byte array");
        }

        byte[] buffer = new byte[BitConverter.ToInt32(rawLength, 0)];
        if (s.Read(buffer, 0, buffer.Length) != buffer.Length)
        {
            throw new SystemException("Did not read byte array properly");
        }

        return buffer;
    }

}

            using System;
            using System.Collections.Generic;
            using System.Text;
            using System.Text.RegularExpressions;  // This is for password validation
            using System.Security.Cryptography;
            using System.Configuration;  // This is where the hash functions reside

            namespace BullyTracker.Common
            {
                public class HashEncryption
                {
                    //public string GenerateHashvalue(string thisPassword)
                    //{
                    //    MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
                    //    byte[] tmpSource;
                    //    byte[] tmpHash;

                    //    tmpSource = ASCIIEncoding.ASCII.GetBytes(thisPassword); // Turn password into byte array
                    //    tmpHash = md5.ComputeHash(tmpSource);

                    //    StringBuilder sOutput = new StringBuilder(tmpHash.Length);
                    //    for (int i = 0; i < tmpHash.Length; i++)
                    //    {
                    //        sOutput.Append(tmpHash[i].ToString("X2"));  // X2 formats to hexadecimal
                    //    }
                    //    return sOutput.ToString();
                    //}
                    //public Boolean VerifyHashPassword(string thisPassword, string thisHash)
                    //{
                    //    Boolean IsValid = false;
                    //    string tmpHash = GenerateHashvalue(thisPassword); // Call the routine on user input
                    //    if (tmpHash == thisHash) IsValid = true;  // Compare to previously generated hash
                    //    return IsValid;
                    //}
                    public string GenerateHashvalue(string toEncrypt, bool useHashing)
                    {
                        byte[] keyArray;
                        byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(toEncrypt);

                        System.Configuration.AppSettingsReader settingsReader = new AppSettingsReader();
                        // Get the key from config file
                        string key = (string)settingsReader.GetValue("SecurityKey", typeof(String));
                        //System.Windows.Forms.MessageBox.Show(key);
                        if (useHashing)
                        {
                            MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
                            keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
                            hashmd5.Clear();
                        }
                        else
                            keyArray = UTF8Encoding.UTF8.GetBytes(key);

                        TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
                        tdes.Key = keyArray;
                        tdes.Mode = CipherMode.ECB;
                        tdes.Padding = PaddingMode.PKCS7;

                        ICryptoTransform cTransform = tdes.CreateEncryptor();
                        byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
                        tdes.Clear();
                        return Convert.ToBase64String(resultArray, 0, resultArray.Length);
                    }
                    /// <summary>
                    /// DeCrypt a string using dual encryption method. Return a DeCrypted clear string
                    /// </summary>
                    /// <param name="cipherString">encrypted string</param>
                    /// <param name="useHashing">Did you use hashing to encrypt this data? pass true is yes</param>
                    /// <returns></returns>
                    public string Decrypt(string cipherString, bool useHashing)
                    {
                        byte[] keyArray;
                        byte[] toEncryptArray = Convert.FromBase64String(cipherString);

                        System.Configuration.AppSettingsReader settingsReader = new AppSettingsReader();
                        //Get your key from config file to open the lock!
                        string key = (string)settingsReader.GetValue("SecurityKey", typeof(String));

                        if (useHashing)
                        {
                            MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
                            keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
                            hashmd5.Clear();
                        }
                        else
                            keyArray = UTF8Encoding.UTF8.GetBytes(key);

                        TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
                        tdes.Key = keyArray;
                        tdes.Mode = CipherMode.ECB;
                        tdes.Padding = PaddingMode.PKCS7;

                        ICryptoTransform cTransform = tdes.CreateDecryptor();
                        byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

                        tdes.Clear();
                        return UTF8Encoding.UTF8.GetString(resultArray);
                    }


                }

            }

为简单起见，我为自己制作了这个用于非加密目的的函数：将“yourpassphrase”替换为您的密码......

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Security.Cryptography;
using System.IO;

 namespace My
{
    public class strCrypto
    {
        // This constant string is used as a "salt" value for the PasswordDeriveBytes function calls.
    // This size of the IV (in bytes) must = (keysize / 8).  Default keysize is 256, so the IV must be
    // 32 bytes long.  Using a 16 character string here gives us 32 bytes when converted to a byte array.
    private const string initVector = "r5dm5fgm24mfhfku";
    private const string passPhrase = "yourpassphrase"; // email password encryption password

    // This constant is used to determine the keysize of the encryption algorithm.
    private const int keysize = 256;

    public static string encryptString(string plainText)
    {
        //if the plaintext  is empty or null string just return an empty string
        if (plainText == "" || plainText == null )
        {
            return "";
        }

        byte[] initVectorBytes = Encoding.UTF8.GetBytes(initVector);
        byte[] plainTextBytes = Encoding.UTF8.GetBytes(plainText);
        PasswordDeriveBytes password = new PasswordDeriveBytes(passPhrase, null);
        byte[] keyBytes = password.GetBytes(keysize / 8);
        RijndaelManaged symmetricKey = new RijndaelManaged();
        symmetricKey.Mode = CipherMode.CBC;
        ICryptoTransform encryptor = symmetricKey.CreateEncryptor(keyBytes, initVectorBytes);
        MemoryStream memoryStream = new MemoryStream();
        CryptoStream cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write);
        cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
        cryptoStream.FlushFinalBlock();
        byte[] cipherTextBytes = memoryStream.ToArray();
        memoryStream.Close();
        cryptoStream.Close();
        return Convert.ToBase64String(cipherTextBytes);
    }

    public static string decryptString(string cipherText)
    {
        //if the ciphertext is empty or null string just return an empty string
        if (cipherText == "" || cipherText == null )
        {
            return "";
        }

        byte[] initVectorBytes = Encoding.ASCII.GetBytes(initVector);
        byte[] cipherTextBytes = Convert.FromBase64String(cipherText);
        PasswordDeriveBytes password = new PasswordDeriveBytes(passPhrase, null);
        byte[] keyBytes = password.GetBytes(keysize / 8);
        RijndaelManaged symmetricKey = new RijndaelManaged();
        symmetricKey.Mode = CipherMode.CBC;
        ICryptoTransform decryptor = symmetricKey.CreateDecryptor(keyBytes, initVectorBytes);
        MemoryStream memoryStream = new MemoryStream(cipherTextBytes);
        CryptoStream cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read);
        byte[] plainTextBytes = new byte[cipherTextBytes.Length];
        int decryptedByteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length);
        memoryStream.Close();
        cryptoStream.Close();
        return Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount);
    }


}

}

下面是使用 AES CBC 模式在 C# 中加密字符串的简单示例，该模式具有随机 IV 和 HMAC 以及密码派生密钥，以显示基本的移动部件：

private byte[] EncryptBytes(byte[] key, byte[] plaintext)
{
    using (var cipher = new RijndaelManaged { Key = key })
    {
        using (var encryptor = cipher.CreateEncryptor())
        {
            var ciphertext = encryptor.TransformFinalBlock(plaintext, 0, plaintext.Length);

            // IV is prepended to ciphertext
            return cipher.IV.Concat(ciphertext).ToArray();
        }
    }
}

private byte[] DecryptBytes(byte[] key, byte[] packed)
{
    using (var cipher = new RijndaelManaged { Key = key })
    {
        int ivSize = cipher.BlockSize / 8;

        cipher.IV = packed.Take(ivSize).ToArray();

        using (var encryptor = cipher.CreateDecryptor())
        {
            return encryptor.TransformFinalBlock(packed, ivSize, packed.Length - ivSize);
        }
    }
}

private byte[] AddMac(byte[] key, byte[] data)
{
    using (var hmac = new HMACSHA256(key))
    {
        var macBytes = hmac.ComputeHash(data);

        // HMAC is appended to data
        return data.Concat(macBytes).ToArray();
    }
}

private bool BadMac(byte[] found, byte[] computed)
{
    int mismatch = 0;

    // Aim for consistent timing regardless of inputs
    for (int i = 0; i < found.Length; i++)
    {
        mismatch += found[i] == computed[i] ? 0 : 1;
    }

    return mismatch != 0;
}

private byte[] RemoveMac(byte[] key, byte[] data)
{
    using (var hmac = new HMACSHA256(key))
    {
        int macSize = hmac.HashSize / 8;

        var packed = data.Take(data.Length - macSize).ToArray();

        var foundMac = data.Skip(packed.Length).ToArray();

        var computedMac = hmac.ComputeHash(packed);

        if (this.BadMac(foundMac, computedMac))
        {
            throw new Exception("Bad MAC");
        }

        return packed;
    }            
}

private List<byte[]> DeriveTwoKeys(string password)
{
    var salt = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8 };

    var kdf = new Rfc2898DeriveBytes(password, salt, 10000);

    var bytes = kdf.GetBytes(32); // Two keys 128 bits each

    return new List<byte[]> { bytes.Take(16).ToArray(), bytes.Skip(16).ToArray() };
}

public byte[] EncryptString(string password, String message)
{
    var keys = this.DeriveTwoKeys(password);

    var plaintext = Encoding.UTF8.GetBytes(message);

    var packed = this.EncryptBytes(keys[0], plaintext);

    return this.AddMac(keys[1], packed);
}

public String DecryptString(string password, byte[] secret)
{
    var keys = this.DeriveTwoKeys(password);

    var packed = this.RemoveMac(keys[1], secret);

    var plaintext = this.DecryptBytes(keys[0], packed);

    return Encoding.UTF8.GetString(plaintext);
}

public void Example()
{
    var password = "correcthorsebatterystaple";

    var secret = this.EncryptString(password, "Hello World");

    Console.WriteLine("secret: " + BitConverter.ToString(secret));

    var recovered = this.DecryptString(password, secret);

    Console.WriteLine(recovered);
}

从类似的问题复制了我的答案：C#的简单双向加密。

基于多个答案和评论。

• 加密文本前面的随机初始化向量 （@jbtule）
• 使用 TransformFinalBlock（） 而不是 MemoryStream （@RenniePet）
• 没有预先填充的密钥，以避免任何人复制和粘贴灾难
• 正确处置和使用模式

法典：

/// <summary>
/// Simple encryption/decryption using a random initialization vector
/// and prepending it to the crypto text.
/// </summary>
/// <remarks>Based on multiple answers in https://stackoverflow.com/questions/165808/simple-two-way-encryption-for-c-sharp </remarks>
public class SimpleAes : IDisposable
{
    /// <summary>
    ///     Initialization vector length in bytes.
    /// </summary>
    private const int IvBytes = 16;

    /// <summary>
    ///     Must be exactly 16, 24 or 32 characters long.
    /// </summary>
    private static readonly byte[] Key = Convert.FromBase64String("FILL ME WITH 16, 24 OR 32 CHARS");

    private readonly UTF8Encoding _encoder;
    private readonly ICryptoTransform _encryptor;
    private readonly RijndaelManaged _rijndael;

    public SimpleAes()
    {
        _rijndael = new RijndaelManaged {Key = Key};
        _rijndael.GenerateIV();
        _encryptor = _rijndael.CreateEncryptor();
        _encoder = new UTF8Encoding();
    }

    public string Decrypt(string encrypted)
    {
        return _encoder.GetString(Decrypt(Convert.FromBase64String(encrypted)));
    }

    public void Dispose()
    {
        _rijndael.Dispose();
        _encryptor.Dispose();
    }

    public string Encrypt(string unencrypted)
    {
        return Convert.ToBase64String(Encrypt(_encoder.GetBytes(unencrypted)));
    }

    private byte[] Decrypt(byte[] buffer)
    {
        // IV is prepended to cryptotext
        byte[] iv = buffer.Take(IvBytes).ToArray();
        using (ICryptoTransform decryptor = _rijndael.CreateDecryptor(_rijndael.Key, iv))
        {
            return decryptor.TransformFinalBlock(buffer, IvBytes, buffer.Length - IvBytes);
        }
    }

    private byte[] Encrypt(byte[] buffer)
    {
        // Prepend cryptotext with IV
        byte[] inputBuffer = _rijndael.IV.Concat(buffer).ToArray();
        return _encryptor.TransformFinalBlock(inputBuffer, IvBytes, buffer.Length);
    }
}

您必须使用 System.Security.Cryptography 使用命名空间;useHashing 是 bool 类型，可以是 true 或 false。字符串变量“key”对于加密和解密应相同

//Encryption
public string EncryptText(string toEncrypt, bool useHashing)
    {
        try
        {
            byte[] keyArray;
            byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(toEncrypt);

            string key = "String Key Value"; //Based on this key stirng is encrypting
            //System.Windows.Forms.MessageBox.Show(key);
            //If hashing use get hashcode regards to your key
            if (useHashing)
            {
                MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
                keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
                //Always release the resources and flush data
                //of the Cryptographic service provide. Best Practice

                hashmd5.Clear();
            }
            else
                keyArray = UTF8Encoding.UTF8.GetBytes(key);

            TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
            //set the secret key for the tripleDES algorithm
            tdes.Key = keyArray;
            //mode of operation. there are other 4 modes. We choose ECB(Electronic code Book)
            tdes.Mode = CipherMode.ECB;
            //padding mode(if any extra byte added)
            tdes.Padding = PaddingMode.PKCS7;

            ICryptoTransform cTransform = tdes.CreateEncryptor();
            //transform the specified region of bytes array to resultArray
            byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0,          toEncryptArray.Length);
            //Release resources held by TripleDes Encryptor
            tdes.Clear();
            //Return the encrypted data into unreadable string format
            return Convert.ToBase64String(resultArray, 0, resultArray.Length);
        }
        catch (Exception e)
        {
            throw e;
        }
    }

    //Decryption
    public string DecryptText(string cipherString, bool useHashing)
    {

        try
        {
            byte[] keyArray;
            //get the byte code of the string

            byte[] toEncryptArray = Convert.FromBase64String(cipherString);

            string key = "String Key Value"; //Based on this key string is decrypted

            if (useHashing)
            {
                //if hashing was used get the hash code with regards to your key
                MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
                keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
                //release any resource held by the MD5CryptoServiceProvider

                hashmd5.Clear();
            }
            else
            {
                //if hashing was not implemented get the byte code of the key
                keyArray = UTF8Encoding.UTF8.GetBytes(key);
            }

            TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
            //set the secret key for the tripleDES algorithm
            tdes.Key = keyArray;
            //mode of operation. there are other 4 modes.
            //We choose ECB(Electronic code Book)

            tdes.Mode = CipherMode.ECB;
            //padding mode(if any extra byte added)
            tdes.Padding = PaddingMode.PKCS7;

            ICryptoTransform cTransform = tdes.CreateDecryptor();
            byte[] resultArray = cTransform.TransformFinalBlock
                    (toEncryptArray, 0, toEncryptArray.Length);
            //Release resources held by TripleDes Encryptor
            tdes.Clear();
            //return the Clear decrypted TEXT
            return UTF8Encoding.UTF8.GetString(resultArray);
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

这是最初由 ASP Snippets 提供的简单代码段

using System.Text;
using System.Security.Cryptography;
using System.IO;


 private string Encrypt(string clearText)
    {
        string EncryptionKey = "yourkey";
        byte[] clearBytes = 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;
    }

 private string Decrypt(string cipherText)
    {
        string EncryptionKey = "yourkey";
        cipherText = cipherText.Replace(" ", "+");
        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 = Encoding.Unicode.GetString(ms.ToArray());
            }
        }
        return cipherText;
    }

加密

public string EncryptString(string inputString)
{
    MemoryStream memStream = null;
    try
    {
        byte[] key = { };
        byte[] IV = { 12, 21, 43, 17, 57, 35, 67, 27 };
        string encryptKey = "aXb2uy4z"; // MUST be 8 characters
        key = Encoding.UTF8.GetBytes(encryptKey);
        byte[] byteInput = Encoding.UTF8.GetBytes(inputString);
        DESCryptoServiceProvider provider = new DESCryptoServiceProvider();
        memStream = new MemoryStream();
        ICryptoTransform transform = provider.CreateEncryptor(key, IV);
        CryptoStream cryptoStream = new CryptoStream(memStream, transform, CryptoStreamMode.Write);
        cryptoStream.Write(byteInput, 0, byteInput.Length);
        cryptoStream.FlushFinalBlock();
    }
    catch (Exception ex)
    {
        Response.Write(ex.Message);
    }
    return Convert.ToBase64String(memStream.ToArray());
}

解密：

public string DecryptString(string inputString)
{
    MemoryStream memStream = null;
    try
    {
        byte[] key = { };
        byte[] IV = { 12, 21, 43, 17, 57, 35, 67, 27 };
        string encryptKey = "aXb2uy4z"; // MUST be 8 characters
        key = Encoding.UTF8.GetBytes(encryptKey);
        byte[] byteInput = new byte[inputString.Length];
        byteInput = Convert.FromBase64String(inputString);
        DESCryptoServiceProvider provider = new DESCryptoServiceProvider();
        memStream = new MemoryStream();
        ICryptoTransform transform = provider.CreateDecryptor(key, IV);
        CryptoStream cryptoStream = new CryptoStream(memStream, transform, CryptoStreamMode.Write);
        cryptoStream.Write(byteInput, 0, byteInput.Length);
        cryptoStream.FlushFinalBlock();
    }
    catch (Exception ex)
    {
        Response.Write(ex.Message);
    }

    Encoding encoding1 = Encoding.UTF8;
    return encoding1.GetString(memStream.ToArray());
}

一个安全哈希数据的好算法是 BCrypt：

除了加入盐来防止彩虹桌攻击外， bcrypt 是一个自适应函数：随着时间的推移，迭代计数可以是 增加以使其速度变慢，因此它仍然能抵抗蛮力 即使计算能力不断提高，搜索攻击也是如此。

BCrypt 有一个很好的 .NET 实现，也可以作为 NuGet 包使用。

免责声明：此解决方案应仅用于未向公众公开的静态数据（例如，配置文件或数据库）。只有在这种情况下，由于维护成本较低，快速和脏的解决方案才能被认为比 @jbtule 的解决方案更好。

原文： 我发现 jbtule 的答案对于快速而肮脏的安全 AES 字符串加密有点复杂，而 Brett 的答案有一个错误，初始化向量是一个固定值，使其容易受到填充攻击，所以我修复了 Brett 的代码并添加了一个随机 IV，该 IV 被添加到芯片字符串中，每次加密都为相同值创建不同的加密值：

加密：

public static string Encrypt(string clearText)
{            
    byte[] clearBytes = Encoding.Unicode.GetBytes(clearText);
    using (Aes encryptor = Aes.Create())
    {
        byte[] IV = new byte[15];
        rand.NextBytes(IV);
        Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, IV);
        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(IV) + Convert.ToBase64String(ms.ToArray());
        }
    }
    return clearText;
}

解密：

public static string Decrypt(string cipherText)
{
    byte[] IV = Convert.FromBase64String(cipherText.Substring(0, 20));
    cipherText = cipherText.Substring(20).Replace(" ", "+");
    byte[] cipherBytes = Convert.FromBase64String(cipherText);
    using (Aes encryptor = Aes.Create())
    {
        Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, IV);
        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 = Encoding.Unicode.GetString(ms.ToArray());
        }
    }
    return cipherText;
}

将 EncryptionKey 替换为您的密钥。 在我的实现中，密钥保存在配置文件 （web.config\app.config） 中，因为您不应该将其硬编码保存。配置文件也应加密，以便密钥不会以明文形式保存在其中。

protected static string _Key = "";
protected static string EncryptionKey
{
    get
    {
        if (String.IsNullOrEmpty(_Key))
        {
            _Key = ConfigurationManager.AppSettings["AESKey"].ToString();
        }

        return _Key;
    }
}

AES算法：

public static class CryptographyProvider
    {
        public static string EncryptString(string plainText, out string Key)
        {
            if (plainText == null || plainText.Length <= 0)
                throw new ArgumentNullException("plainText");

            using (Aes _aesAlg = Aes.Create())
            {
                Key = Convert.ToBase64String(_aesAlg.Key);
                ICryptoTransform _encryptor = _aesAlg.CreateEncryptor(_aesAlg.Key, _aesAlg.IV);

                using (MemoryStream _memoryStream = new MemoryStream())
                {
                    _memoryStream.Write(_aesAlg.IV, 0, 16);
                    using (CryptoStream _cryptoStream = new CryptoStream(_memoryStream, _encryptor, CryptoStreamMode.Write))
                    {
                        using (StreamWriter _streamWriter = new StreamWriter(_cryptoStream))
                        {
                            _streamWriter.Write(plainText);
                        }
                        return Convert.ToBase64String(_memoryStream.ToArray());
                    }
                }
            }
        }
        public static string DecryptString(string cipherText, string Key)
        {

            if (string.IsNullOrEmpty(cipherText))
                throw new ArgumentNullException("cipherText");
            if (string.IsNullOrEmpty(Key))
                throw new ArgumentNullException("Key");

            string plaintext = null;

            byte[] _initialVector = new byte[16];
            byte[] _Key = Convert.FromBase64String(Key);
            byte[] _cipherTextBytesArray = Convert.FromBase64String(cipherText);
            byte[] _originalString = new byte[_cipherTextBytesArray.Length - 16];

            Array.Copy(_cipherTextBytesArray, 0, _initialVector, 0, _initialVector.Length);
            Array.Copy(_cipherTextBytesArray, 16, _originalString, 0, _cipherTextBytesArray.Length - 16);

            using (Aes _aesAlg = Aes.Create())
            {
                _aesAlg.Key = _Key;
                _aesAlg.IV = _initialVector;
                ICryptoTransform decryptor = _aesAlg.CreateDecryptor(_aesAlg.Key, _aesAlg.IV);

                using (MemoryStream _memoryStream = new MemoryStream(_originalString))
                {
                    using (CryptoStream _cryptoStream = new CryptoStream(_memoryStream, decryptor, CryptoStreamMode.Read))
                    {
                        using (StreamReader _streamReader = new StreamReader(_cryptoStream))
                        {
                            plaintext = _streamReader.ReadToEnd();
                        }
                    }
                }
            }
            return plaintext;
        }
    }

支持mattmanser回答。下面是一个使用 MachineKey 类加密/解密 URL 安全值的示例。

请记住，如前所述，这将使用计算机配置设置 （https://msdn.microsoft.com/en-us/library/ff649308.aspx）。您可以在 web.config 文件中手动设置加密和解密密钥/算法（如果您的站点在多个服务器上运行，则特别需要此密钥/算法）。您可以从 IIS 生成密钥（请参阅此处：https://blogs.msdn.microsoft.com/vijaysk/2009/05/13/iis-7-tip-10-you-can-generate-machine-keys-from-the-iis-manager/），也可以使用联机密钥生成器，例如：http://www.developerfusion.com/tools/generatemachinekey/

    private static readonly UTF8Encoding Encoder = new UTF8Encoding();

    public static string Encrypt(string unencrypted)
    {
        if (string.IsNullOrEmpty(unencrypted)) 
            return string.Empty;

        try
        {
            var encryptedBytes = MachineKey.Protect(Encoder.GetBytes(unencrypted));

            if (encryptedBytes != null && encryptedBytes.Length > 0)
                return HttpServerUtility.UrlTokenEncode(encryptedBytes);    
        }
        catch (Exception)
        {
            return string.Empty;
        }

        return string.Empty;
    }

    public static string Decrypt(string encrypted)
    {
        if (string.IsNullOrEmpty(encrypted)) 
            return string.Empty;

        try
        {
            var bytes = HttpServerUtility.UrlTokenDecode(encrypted);
            if (bytes != null && bytes.Length > 0)
            {
                var decryptedBytes = MachineKey.Unprotect(bytes);
                if(decryptedBytes != null && decryptedBytes.Length > 0)
                    return Encoder.GetString(decryptedBytes);
            }

        }
        catch (Exception)
        {
            return string.Empty;
        }

        return string.Empty;
    }

加密是编程中非常普遍的问题。我认为最好安装一个软件包来为您完成任务。也许是一个简单的开源 NuGet 项目，例如 Simple Aes Encryption

密钥在配置文件中，因此在生产环境中很容易更改，我看不出任何缺点。

<MessageEncryption>
  <EncryptionKey KeySize="256" Key="3q2+796tvu/erb7v3q2+796tvu/erb7v3q2+796tvu8="/>
</MessageEncryption>

用于 AES-GCM 加密的 BouncyCastle 的替代方案是 libsodium-net。它包装了 libsodium C 库。一个很好的优点是它在 CPU 中使用 AES-NI 扩展进行非常快速的加密。不利的一面是，如果 CPU 没有扩展，它根本无法工作。没有软件回退。

参考 c# 中的加密和解密字符串，我找到了一个很好的解决方案：

static readonly string PasswordHash = "P@@Sw0rd";
static readonly string SaltKey = "S@LT&KEY";
static readonly string VIKey = "@1B2c3D4e5F6g7H8";

对于加密

public static string Encrypt(string plainText)
{
    byte[] plainTextBytes = Encoding.UTF8.GetBytes(plainText);

    byte[] keyBytes = new Rfc2898DeriveBytes(PasswordHash, Encoding.ASCII.GetBytes(SaltKey)).GetBytes(256 / 8);
    var symmetricKey = new RijndaelManaged() { Mode = CipherMode.CBC, Padding = PaddingMode.Zeros };
    var encryptor = symmetricKey.CreateEncryptor(keyBytes, Encoding.ASCII.GetBytes(VIKey));

    byte[] cipherTextBytes;

    using (var memoryStream = new MemoryStream())
    {
        using (var cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
        {
            cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
            cryptoStream.FlushFinalBlock();
            cipherTextBytes = memoryStream.ToArray();
            cryptoStream.Close();
        }
        memoryStream.Close();
    }
    return Convert.ToBase64String(cipherTextBytes);
}

用于解密

public static string Decrypt(string encryptedText)
{
    byte[] cipherTextBytes = Convert.FromBase64String(encryptedText);
    byte[] keyBytes = new Rfc2898DeriveBytes(PasswordHash, Encoding.ASCII.GetBytes(SaltKey)).GetBytes(256 / 8);
    var symmetricKey = new RijndaelManaged() { Mode = CipherMode.CBC, Padding = PaddingMode.None };

    var decryptor = symmetricKey.CreateDecryptor(keyBytes, Encoding.ASCII.GetBytes(VIKey));
    var memoryStream = new MemoryStream(cipherTextBytes);
    var cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read);
    byte[] plainTextBytes = new byte[cipherTextBytes.Length];

    int decryptedByteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length);
    memoryStream.Close();
    cryptoStream.Close();
    return Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount).TrimEnd("\0".ToCharArray());
}

using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

public class Program
{
    public static void Main()
    {
        var key = Encoding.UTF8.GetBytes("SUkbqO2ycDo7QwpR25kfgmC7f8CoyrZy");
        var data = Encoding.UTF8.GetBytes("testData");

        //Encrypt data
        var encrypted = CryptoHelper.EncryptData(data,key);

        //Decrypt data
        var decrypted = CryptoHelper.DecryptData(encrypted,key);

        //Display result
        Console.WriteLine(Encoding.UTF8.GetString(decrypted));
    }
}

public static class CryptoHelper
{
    public static byte[] EncryptData(byte[] data, byte[] key)
    {
        using (var aesAlg = Aes.Create())
        {
            aesAlg.Mode = CipherMode.CBC;
            using (var encryptor = aesAlg.CreateEncryptor(key, aesAlg.IV))
            {
                using (var msEncrypt = new MemoryStream())
                {
                    msEncrypt.Write(aesAlg.IV, 0, aesAlg.IV.Length);

                    using (var csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                        csEncrypt.Write(data, 0, data.Length);

                    return msEncrypt.ToArray();
                }
            }
        }

    }

    public static byte[] DecryptData(byte[] encrypted, byte[] key)
    {
        var iv = new byte[16];
        Buffer.BlockCopy(encrypted, 0, iv, 0, iv.Length);
        using (var aesAlg = Aes.Create())
        {
            aesAlg.Mode = CipherMode.CBC;
            using (var decryptor = aesAlg.CreateDecryptor(key, iv))
            {
                using (var msDecrypt = new MemoryStream(encrypted, iv.Length, encrypted.Length - iv.Length))
                {
                    using (var csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                    {
                        using (var resultStream = new MemoryStream())
                        {
                            csDecrypt.CopyTo(resultStream);
                            return resultStream.ToArray();
                        }
                    }
                }
            }
        }
    }
}

下面是如何使用 Bouncy castle 包完成 AES-GCM 加密/解密的示例。

我在谷歌上搜索了从 GOlang api 解密数据的可能性时发现了该示例：crypto/aes

const (
    gcmBlockSize         = 16 // this is key size
    gcmTagSize           = 16 // this is mac
    gcmStandardNonceSize = 12 // this is nonce
)

func encrypt(data []byte, passphrase string) []byte {
    block, _ := aes.NewCipher([]byte(createHash(passphrase)))
    gcm, err := cipher.NewGCM(block)
    if err != nil {
        panic(err.Error())
    }
    nonce := make([]byte, gcm.NonceSize())
    if _, err = io.ReadFull(rand.Reader, nonce); err != nil {
        panic(err.Error())
    }
    ciphertext := gcm.Seal(nonce, nonce, data, nil)
    return ciphertext
}

.Net 示例的工作方式类似于带有密钥（256 位）、mac（128 位）和随机数（96 位）的超级按钮。

以下代码是 Ghazal 对类似问题的回答的改进版本。

public class EncryptionHelper
{
    private Aes aesEncryptor;

    public EncryptionHelper()
    {
    }

    private void BuildAesEncryptor(string key)
    {
        aesEncryptor = Aes.Create();
        var pdb = new Rfc2898DeriveBytes(key, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
        aesEncryptor.Key = pdb.GetBytes(32);
        aesEncryptor.IV = pdb.GetBytes(16);
    }

    public string EncryptString(string clearText, string key)
    {
        BuildAesEncryptor(key);
        var clearBytes = Encoding.Unicode.GetBytes(clearText);
        using (var ms = new MemoryStream())
        {
            using (var cs = new CryptoStream(ms, aesEncryptor.CreateEncryptor(), CryptoStreamMode.Write))
            {
                cs.Write(clearBytes, 0, clearBytes.Length);
            }
            var encryptedText = Convert.ToBase64String(ms.ToArray());
            return encryptedText;
        }
    }

    public string DecryptString(string cipherText, string key)
    {
        BuildAesEncryptor(key);
        cipherText = cipherText.Replace(" ", "+");
        var cipherBytes = Convert.FromBase64String(cipherText);
        using (var ms = new MemoryStream())
        {
            using (var cs = new CryptoStream(ms, aesEncryptor.CreateDecryptor(), CryptoStreamMode.Write))
            {
                cs.Write(cipherBytes, 0, cipherBytes.Length);
            }
            var clearText = Encoding.Unicode.GetString(ms.ToArray());
            return clearText;
        }
    }
}

以下示例演示如何加密和解密示例数据：

    // This constant is used to determine the keysize of the encryption algorithm in bits.
    // We divide this by 8 within the code below to get the equivalent number of bytes.
    private const int Keysize = 128;

    // This constant determines the number of iterations for the password bytes generation function.
    private const int DerivationIterations = 1000;

    public static string Encrypt(string plainText, string passPhrase)
    {
        // Salt and IV is randomly generated each time, but is preprended to encrypted cipher text
        // so that the same Salt and IV values can be used when decrypting.  
        var saltStringBytes = GenerateBitsOfRandomEntropy(16);
        var ivStringBytes = GenerateBitsOfRandomEntropy(16);
        var plainTextBytes = Encoding.UTF8.GetBytes(plainText);
        using (var password = new Rfc2898DeriveBytes(passPhrase, saltStringBytes, DerivationIterations))
        {
            var keyBytes = password.GetBytes(Keysize / 8);
            using (var symmetricKey = new RijndaelManaged())
            {
                symmetricKey.BlockSize = 128;
                symmetricKey.Mode = CipherMode.CBC;
                symmetricKey.Padding = PaddingMode.PKCS7;
                using (var encryptor = symmetricKey.CreateEncryptor(keyBytes, ivStringBytes))
                {
                    using (var memoryStream = new MemoryStream())
                    {
                        using (var cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
                        {
                            cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
                            cryptoStream.FlushFinalBlock();
                            // Create the final bytes as a concatenation of the random salt bytes, the random iv bytes and the cipher bytes.
                            var cipherTextBytes = saltStringBytes;
                            cipherTextBytes = cipherTextBytes.Concat(ivStringBytes).ToArray();
                            cipherTextBytes = cipherTextBytes.Concat(memoryStream.ToArray()).ToArray();
                            memoryStream.Close();
                            cryptoStream.Close();
                            return Convert.ToBase64String(cipherTextBytes);
                        }
                    }
                }
            }
        }
    }

    public static string Decrypt(string cipherText, string passPhrase)
    {
        // Get the complete stream of bytes that represent:
        // [32 bytes of Salt] + [32 bytes of IV] + [n bytes of CipherText]
        var cipherTextBytesWithSaltAndIv = Convert.FromBase64String(cipherText);
        // Get the saltbytes by extracting the first 32 bytes from the supplied cipherText bytes.
        var saltStringBytes = cipherTextBytesWithSaltAndIv.Take(Keysize / 8).ToArray();
        // Get the IV bytes by extracting the next 32 bytes from the supplied cipherText bytes.
        var ivStringBytes = cipherTextBytesWithSaltAndIv.Skip(Keysize / 8).Take(Keysize / 8).ToArray();
        // Get the actual cipher text bytes by removing the first 64 bytes from the cipherText string.
        var cipherTextBytes = cipherTextBytesWithSaltAndIv.Skip((Keysize / 8) * 2).Take(cipherTextBytesWithSaltAndIv.Length - ((Keysize / 8) * 2)).ToArray();

        using (var password = new Rfc2898DeriveBytes(passPhrase, saltStringBytes, DerivationIterations))
        {
            var keyBytes = password.GetBytes(Keysize / 8);
            using (var symmetricKey = new RijndaelManaged())
            {
                symmetricKey.BlockSize = 128;
                symmetricKey.Mode = CipherMode.CBC;
                symmetricKey.Padding = PaddingMode.PKCS7;
                using (var decryptor = symmetricKey.CreateDecryptor(keyBytes, ivStringBytes))
                {
                    using (var memoryStream = new MemoryStream(cipherTextBytes))
                    {
                        using (var cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read))
                        {
                            var plainTextBytes = new byte[cipherTextBytes.Length];
                            var decryptedByteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length);
                            memoryStream.Close();
                            cryptoStream.Close();
                            return Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount);
                        }
                    }
                }
            }
        }
    }

    private static byte[] GenerateBitsOfRandomEntropy(int size)
    {
        // 32 Bytes will give us 256 bits.
        // 16 Bytes will give us 128 bits.
        var randomBytes = new byte[size]; 
        using (var rngCsp = new RNGCryptoServiceProvider())
        {
            // Fill the array with cryptographically secure random bytes.
            rngCsp.GetBytes(randomBytes);
        }
        return randomBytes;
    }

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Security.Cryptography;
using System.IO;
using System.Text;  

/// <summary>
/// Summary description for Encryption
/// </summary>
public class Encryption
{
    public TripleDES CreateDES(string key)
    {
        MD5 md5 = new MD5CryptoServiceProvider();
        TripleDES des = new TripleDESCryptoServiceProvider();
        des.Key = md5.ComputeHash(Encoding.Unicode.GetBytes(key));
        des.IV = new byte[des.BlockSize / 8];
        return des;
    }
    public  byte[] Encryptiondata(string PlainText)
    {
        TripleDES des = CreateDES("DreamMLMKey");
        ICryptoTransform ct = des.CreateEncryptor();
        byte[] input = Encoding.Unicode.GetBytes(PlainText);
        return ct.TransformFinalBlock(input, 0, input.Length);
    }

    public string Decryptiondata(string CypherText)
    {
        string stringToDecrypt = CypherText.Replace(" ", "+");
        int len = stringToDecrypt.Length;
        byte[] inputByteArray = Convert.FromBase64String(stringToDecrypt); 

        byte[] b = Convert.FromBase64String(CypherText);
        TripleDES des = CreateDES("DreamMLMKey");
        ICryptoTransform ct = des.CreateDecryptor();
        byte[] output = ct.TransformFinalBlock(b, 0, b.Length);
        return Encoding.Unicode.GetString(output);
    }
    public string Decryptiondataurl(string CypherText)
    {
        string newcyperttext=CypherText.Replace(' ', '+');
        byte[] b = Convert.FromBase64String(newcyperttext);
        TripleDES des = CreateDES("DreamMLMKey");
        ICryptoTransform ct = des.CreateDecryptor();
        byte[] output = ct.TransformFinalBlock(b, 0, b.Length);
        return Encoding.Unicode.GetString(output);
    }


    #region  encryption & Decription
    public  string Encrypt(string input, string key)
    {
        byte[] inputArray = UTF8Encoding.UTF8.GetBytes(input);
        TripleDESCryptoServiceProvider tripleDES = new TripleDESCryptoServiceProvider();
        tripleDES.Key = UTF8Encoding.UTF8.GetBytes(key);
        tripleDES.Mode = CipherMode.ECB;
        tripleDES.Padding = PaddingMode.PKCS7;
        ICryptoTransform cTransform = tripleDES.CreateEncryptor();
        byte[] resultArray = cTransform.TransformFinalBlock(inputArray, 0, inputArray.Length);
        tripleDES.Clear();
        return Convert.ToBase64String(resultArray, 0, resultArray.Length);
    }
    public  string Decrypt(string input, string key)
    {
        byte[] inputArray = Convert.FromBase64String(input);
        TripleDESCryptoServiceProvider tripleDES = new TripleDESCryptoServiceProvider();
        tripleDES.Key = UTF8Encoding.UTF8.GetBytes(key);
        tripleDES.Mode = CipherMode.ECB;
        tripleDES.Padding = PaddingMode.PKCS7;
        ICryptoTransform cTransform = tripleDES.CreateDecryptor();
        byte[] resultArray = cTransform.TransformFinalBlock(inputArray, 0, inputArray.Length);
        tripleDES.Clear();
        return UTF8Encoding.UTF8.GetString(resultArray);
    }

    public string encrypt(string encryptString)
    {
        string EncryptionKey = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        byte[] clearBytes = Encoding.Unicode.GetBytes(encryptString);
        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();
                }
                encryptString = Convert.ToBase64String(ms.ToArray());
            }
        }
        return encryptString;
    }

    public string Decrypt(string cipherText)
    {
        string EncryptionKey = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        cipherText = cipherText.Replace(" ", "+");
        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 = Encoding.Unicode.GetString(ms.ToArray());
            }
        }
        return cipherText;
    }

    #endregion
}

如何使用带有 BouncyCastle 的 PGPCore 来做到这一点的好例子，非常简单的解决方案：https://blog.bitscry.com/2018/07/05/pgp-encryption-and-decryption-in-c/

我尝试了不同的解决方案，但这最适合我，有些有错误，但这对我来说是完美的。

using (PGP pgp = new PGP())
{
// Generate keys
pgp.GenerateKey(@"C:\TEMP\keys\public.asc", @"C:\TEMP\keys\private.asc", "[email protected]", "password");
// Encrypt file
pgp.EncryptFile(@"C:\TEMP\keys\content.txt", @"C:\TEMP\keys\content__encrypted.pgp", @"C:\TEMP\keys\public.asc", true, true);
// Encrypt and sign file
pgp.EncryptFileAndSign(@"C:\TEMP\keys\content.txt", @"C:\TEMP\keys\content__encrypted_signed.pgp", @"C:\TEMP\keys\public.asc", @"C:\TEMP\keys\private.asc", "password", true, true);
// Decrypt file
pgp.DecryptFile(@"C:\TEMP\keys\content__encrypted.pgp", @"C:\TEMP\keys\content__decrypted.txt", @"C:\TEMP\keys\private.asc", "password");
// Decrypt signed file
pgp.DecryptFile(@"C:\TEMP\keys\content__encrypted_signed.pgp", @"C:\TEMP\keys\content__decrypted_signed.txt", @"C:\TEMP\keys\private.asc", "password");

// Encrypt stream
using (FileStream inputFileStream = new FileStream(@"C:\TEMP\keys\content.txt", FileMode.Open))
using (Stream outputFileStream = File.Create(@"C:\TEMP\keys\content__encrypted2.pgp"))
using (Stream publicKeyStream = new FileStream(@"C:\TEMP\keys\public.asc", FileMode.Open))
    pgp.EncryptStream(inputFileStream, outputFileStream, publicKeyStream, true, true);

// Decrypt stream
using (FileStream inputFileStream = new FileStream(@"C:\TEMP\keys\content__encrypted2.pgp", FileMode.Open))
using (Stream outputFileStream = File.Create(@"C:\TEMP\keys\content__decrypted2.txt"))
using (Stream privateKeyStream = new FileStream(@"C:\TEMP\keys\private.asc", FileMode.Open))
    pgp.DecryptStream(inputFileStream, outputFileStream, privateKeyStream, "password");
}

我有一个名为 X509Crypto 的开源项目，它利用证书来加密和解密字符串。它非常易于使用。以下是如何使用它的示例：

1. 使用 X509Crypto 命令行界面 （CLI） 生成新的加密证书和密钥对

>x509crypto.exe
X509Crypto> makecert -context user -keysize medium -alias myvault

Certificate with thumbprint B31FE7E7AE5229F8186782742CF579197FA859FD was added to X509Alias "myvault" in the user X509Context

X509Crypto>

2. 使用 Encrypt CLI 命令向新的 X509Alias 添加密钥

X509Crypto> encrypt -text -alias myvault -context user -secret apikey -in "80EAF03248965AC2B78090"

Secret apikey has been added to X509Alias myvault in the user X509Context

X509Crypto>

3. 在程序中引用密钥

一旦建立了 X509Alias 并添加了机密，就可以在安装了 Org.X509Crypto nuget 包的程序中检索它们：

using Org.X509Crypto;

namespace SampleApp
{
    class Program
    {
        static void Main(string[] args)
        {
            var Alias = new X509Alias(@"myvault", X509Context.UserReadOnly);
            var apiKey = Alias.RecoverSecret(@"apikey");
        }
    }
}