In today’s digital landscape, securing sensitive information is more critical than ever. If you’re using ASP.NET Core, you might store configuration settings in appsettings.json. However, hardcoding sensitive data like connection strings or API keys in plain text can expose your application to serious risks.

ASP.NET Core has built-in support for encryption through its Data Protection API. This can be used to secure sensitive information. The Data Protection API in ASP.NET Core allows you to easily encrypt and decrypt sensitive data, such as user information, and configuration settings. This article will guide you through encrypting and decrypting sensitive information using ASP.NET Core Data Protection API in your application.

ASP.NET Core includes the Data Protection API by default. You do not need to install additional packages unless you’re storing keys externally (like Azure or Redis). Below are detailed steps for using this Data Protection API to protect sensitive information.

1. 定义加解密封装类

using Microsoft.AspNetCore.DataProtection;namespace EncrytionAndDecryption
{public class EncryptionService{private readonly IDataProtector _protector;// Constructor to initialize the IDataProtector using dependency injectionpublic EncryptionService(IDataProtectionProvider provider){// 'MyPurpose' is a unique string that ensures different protection policies for different purposes_protector = provider.CreateProtector("MyPurpose");}// Method to encrypt plain text datapublic string EncryptData(string plainText){return _protector.Protect(plainText);}// Method to decrypt the encrypted datapublic string DecryptData(string encryptedData){try{return _protector.Unprotect(encryptedData);}catch (Exception ex){// If decryption fails (e.g., data is tampered or invalid), handle the exceptionreturn $"Decryption failed: {ex.Message}";}}}
}

2. DI配置

//第一次运行使用这个配置，会在运行路径生成一个xml的key文件
builder.Services.AddDataProtection().PersistKeysToFileSystem(new DirectoryInfo(AppContext.BaseDirectory))  // Optional: Specify where to store keys.SetApplicationName("Ellis Test");//当你第一次生成xml后，请使用下面的配置，避免重复生成xml，你只需要在你发布完成后，将上面步骤生成的xml拷贝到运行目录下即可
//builder.Services.AddDataProtection()
//            .PersistKeysToFileSystem(new DirectoryInfo(AppContext.BaseDirectory))  // Optional: Specify where to store keys
//            .SetApplicationName("Ellis Test").DisableAutomaticKeyGeneration();// Register the EncryptionService for dependency injection
builder.Services.AddScoped<EncryptionService>();

3. 添加controller

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;namespace EncrytionAndDecryption.Controllers
{[Route("api/[controller]/[action]")][ApiController]public class EnDeController : ControllerBase{private readonly EncryptionService _encryptionService;public EnDeController(EncryptionService encryptionService){_encryptionService = encryptionService;}// Action to encrypt sensitive data[HttpPost]public IActionResult EncryptData(string sensitiveData){// Call the EncryptData method to encrypt the inputvar encryptedData = _encryptionService.EncryptData(sensitiveData);// For demonstration purposes, return the encrypted data to the viewreturn Content($"Encrypted data: {encryptedData}");}// Action to decrypt previously encrypted data[HttpPost]public IActionResult DecryptData(string encryptedData){// Call the DecryptData method to decrypt the encrypted datavar decryptedData = _encryptionService.DecryptData(encryptedData);// For demonstration purposes, return the decrypted data to the viewreturn Content($"Decrypted data: {decryptedData}");}}
}

4. 发布
   发布之前将DI修改如下。并将之前生成的xml文件copy到发布路径下

//当你第一次生成xml后，请使用下面的配置，避免重复生成xml，你只需要在你发布完成后，将上面步骤生成的xml拷贝到运行目录下即可
builder.Services.AddDataProtection().PersistKeysToFileSystem(new DirectoryInfo(AppContext.BaseDirectory))  // Optional: Specify where to store keys.SetApplicationName("Ellis Test").DisableAutomaticKeyGeneration();

5. 运行

dotnet EncrytionAndDecryption.dll --urls "http://localhost:8888"

https://github.com/xdqt/asp.net-core/tree/master/EncrytionAndDecryption

设置存储key的路径