MtdKey.Cipher 2.0.2

MTD Key Cipher

<a href="https://www.nuget.org/packages/MtdKey.Cipher">Nuget Package 2.0.1</a>

🔐 Secure Encrypted Message Exchange Library

Overview

This library provides a robust solution for exchanging encrypted messages between applications that share a predefined object structure. It is ideal for microservices, remote backend servers, APIs, and other distributed systems where structured data integrity is crucial.

By ensuring that both sender and receiver applications recognize the data format, this solution enables seamless integration, secure token validation, and efficient object conversion, reducing complexity in multi-application environments.

🔹 Key Features

• IV Embedded in Encrypted Data → Unlike conventional methods that send the Initialization Vector (IV) separately, this approach embeds the IV within the encrypted message, streamlining transmission and processing.

• Object Conversion & Token Lifetime Validation → Converts structured objects into encrypted tokens while embedding an expiration marker, ensuring tokens remain valid only when properly validated within a predefined timeframe.

• Supports Primitive Types & Arrays → While nested objects are not supported, the system securely handles primitive types (string, int, bool, etc.) and arrays/lists for structured data exchange.

The special AesManager class can be used as a dependent injection in the Asp.Net Web App.

appsettings.json

  "AesOptions": {
    "SecretKey": "[Your secret key]",
    "KeySize": "256"
  },

Program.cs

  builder.Services.AddAesMangerService(options => {
        options.SecretKey = builder.Configuration.GetValue<string>("AesOptions:SecretKey");
        options.KeySize = builder.Configuration.GetValue<int>("AesOptions:KeySize");
  });

Index.cshtml.cs

  public class IndexModel : PageModel
  {
      private readonly IAesManager aesManager;

      public IndexModel(IAesManager aesManager)
      {
          this.aesManager = aesManager;
      }

      public IActionResult OnGet()
      {
            var tokenModel = new TestTokenModel()
            {
                UserName = "John Doe",
                Password = "securekey",
                Items = ["first", "second"]
            }; 

            var encryptedData = aesManager.EncryptStrongToken(tokenModel, TimeSpan.FromSeconds(60));
            if (ValidateStrongToken(encryptedData))
            {
                var decryptedModel = DecryptStrongToken.DecryptModel(encryptedData);
            }}      
        ....
      }

  ....

  }

You can also use extensions for the Aes library

var tokenModel = new TestTokenModel()
{
    UserName = "John Doe",
    Password = "password",
    Items = [ "first", "second" ] 
};

var secretKey = AesCore.GenerateSecretKey();


using Aes aes = Aes.Create();

// It's an extension of the System.Security.Cryptography.Aes class
var tokenEncrypted = aes.EncryptStrongToken(tokenModel, secretKey, TimeSpan.FromSeconds(60));
var tokenDecrypted = aes.DecryptStrongToken<TestTokenModel>(tokenEncrypted, secretKey);

Console.WriteLine($"Decrypted User: {tokenDecrypted.UserName}");
Console.WriteLine($"Decrypted Password: {tokenDecrypted.Password}");
Console.WriteLine($"Decrypted Items: {string.Join(", ", tokenDecrypted.Items)}");

🛠 Installation

Clone the repository and ensure you have **.NET 9 ** installed:

git clone https://github.com/mtdkey/MtdKey.Cipher.git
cd your-repository

Examples of usage are located in the Tests, Api and Web folders.

✅ Limitations

• Supports only primitive types (string, int, bool, etc.).
• Warning! DateTime will be parsed in UTC format. Ensure DateTime is in UTC before encrypting.
• Nested classes are not supported.
• Allows arrays and lists for structured data handling.

🏗 Contributing

Feel free to fork, create issues, and submit pull requests! 🚀
We welcome improvements, feature additions, and optimizations to enhance the library.

License

Copyright (c) – presented by Oleg Bruev.
MTDKey Cipher is free and open-source software licensed under the MIT License.