Implementing OAuth 2.0 and OpenID Connect in a .NET 8.0 web application:
// Startup.cs
public void ConfigureServices(IServiceCollection services)
{
services.AddAuthentication(options =>
{
options.DefaultScheme = CookieAuthenticationDefaults.AuthenticationScheme;
options.DefaultChallengeScheme = OpenIdConnectDefaults.AuthenticationScheme;
})
.AddCookie(CookieAuthenticationDefaults.AuthenticationScheme)
.AddOpenIdConnect(OpenIdConnectDefaults.AuthenticationScheme, options =>
{
options.Authority = "https://example.com/auth";
options.ClientId = "your_client_id";
options.ClientSecret = "your_client_secret";
options.ResponseType = "code";
options.SaveTokens = true;
// Configure token validation parameters
options.TokenValidationParameters = new TokenValidationParameters
{
ValidateIssuer = true,
ValidateAudience = true,
ValidateLifetime = true,
ValidateIssuerSigningKey = true,
ValidIssuer = "https://example.com/auth",
ValidAudience = "your_client_id",
IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("your_signing_key"))
};
// Configure token refresh
options.Events = new OpenIdConnectEvents
{
OnTokenValidated = async context =>
{
// Fetch the access token and refresh token
var accessToken = await context.HttpContext.GetTokenAsync("access_token");
var refreshToken = await context.HttpContext.GetTokenAsync("refresh_token");
// Implement your token refresh logic here
// e.g., check the expiration, fetch a new access token, and update the tokens
}
};
});
services.AddAuthorization(options =>
{
options.AddPolicy("RequireAdminRole", policy =>
policy.RequireRole("admin"));
});
}
// Controllers/HomeController.cs
public class HomeController : Controller
{
private readonly IHttpClientFactory _httpClientFactory;
public HomeController(IHttpClientFactory httpClientFactory)
{
_httpClientFactory = httpClientFactory;
}
[Authorize]
public async Task<IActionResult> Protected()
{
var httpClient = _httpClientFactory.CreateClient();
// Attach the access token to the request
httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", await HttpContext.GetTokenAsync("access_token"));
// Make a request to a protected API endpoint
var response = await httpClient.GetAsync("https://api.example.com/protected");
response.EnsureSuccessStatusCode();
return View();
}
[Authorize(Policy = "RequireAdminRole")]
public IActionResult AdminOnly()
{
return View();
}
}
Let's go through the code scenarios:
- Authentication: In the
Startup.csfile, we configure the authentication options to use the default cookie authentication scheme and the OpenID Connect challenge scheme. - OpenID: We then configure the OpenID Connect options, specifying the authority (identity provider), client ID, and client secret.
- Handling Token Refreshing:
- In the
Startup.csfile, we configure theOpenIdConnectEventsto handle theOnTokenValidatedevent. - Inside the event handler, we fetch the access token and refresh token from the current HTTP context.
- You can then implement your token refresh logic here, such as checking the token expiration, fetching a new access token using the refresh token, and updating the tokens in the HTTP context.
- In the
- Verifying Token Signatures:
- In the
Startup.csfile, we configure theTokenValidationParametersfor the OpenID Connect options. - We set the
ValidateIssuer,ValidateAudience,ValidateLifetime, andValidateIssuerSigningKeyparameters totrue. - We also specify the
ValidIssuer,ValidAudience, andIssuerSigningKeyvalues to ensure that the token signatures are properly validated.
- In the
- Implementing Additional Security Measures:
- In the
HomeController, we use theIHttpClientFactoryto create a new HTTP client instance for making requests to the protected API endpoint. - We attach the access token obtained from the current HTTP context to the request headers, ensuring that the protected API can verify the token.
- This approach helps maintain a separation of concerns between the authentication/authorization logic and the API consumption logic, making it easier to manage and update the application's security mechanisms.
- In the
By incorporating these additional code scenarios, you're adding more robust security measures to your .NET 8.0 web application. The token refresh logic ensures that your application can maintain long-lived user sessions without requiring the user to re-authenticate. The token signature verification helps protect against unauthorized access and token tampering. Finally, the use of the IHttpClientFactory and the attachment of the access token to the API requests demonstrate a best practice for securely communicating with protected resources.
Remember to replace the placeholders (e.g., "your_client_id", "your_client_secret", "your_signing_key") with your actual values obtained from the identity provider.
