Integrate Okta SDK in C# Project
- To start with Okta integration in C#, you should include the Okta SDK in your project by adding the NuGet package. Open the NuGet Package Manager Console and execute:
Install-Package Okta.Sdk
Configure Okta Client
- Create an `okta-appsettings.json` file to hold your Okta configurations. This should include your `OrgUrl`, `ClientId`, `ClientSecret`, and `AuthorizationServerId`.
{
"Okta": {
"OrgUrl": "https://{yourOktaDomain}",
"ClientId": "{yourClientId}",
"ClientSecret": "{yourClientSecret}",
"AuthorizationServerId": "default"
}
}
- Make sure to load these settings in your application startup using the `Microsoft.Extensions.Configuration` library.
Set Up Authentication Context
- Create a new service that implements Okta's authentication flow. Utilize dependency injection to create an Okta client using the configuration defined previously.
public class OktaAuthService
{
private readonly IOktaClient _oktaClient;
public OktaAuthService(IOktaClient oktaClient)
{
_oktaClient = oktaClient;
}
// Implement the method to authenticate users here
}
- Ensure to register the Okta client during the application startup:
services.AddSingleton<IOktaClient>(new OktaClient(new OktaClientConfiguration
{
OrgUrl = configuration["Okta:OrgUrl"],
Token = configuration["Okta:ClientSecret"],
}));
Generate Authorization URL
- To initiate the SSO process, generate an authorization URL that redirects the user to Okta for authentication. Okta uses OAuth/OpenID Connect for this.
public string GenerateAuthorizationUrl()
{
var authorizeUrl = new UriBuilder(_oktaClient.Configuration.OrgUrl)
{
Path = "/oauth2/default/v1/authorize",
Query = "client_id={yourClientId}&response_type=code&scope=openid&redirect_uri={yourRedirectUri}&state={state}&nonce={nonce}"
};
return authorizeUrl.ToString();
}
- This URL directs the user to Okta's login, and upon successful login, the user is redirected back with an authorization code in the query string.
Exchange Authorization Code for Tokens
- After receiving the authorization code, your application must exchange it for an access token. Use the Okta SDK to handle this OAuth flow.
public async Task<IOAuthTokenResponse> ExchangeCodeForTokenAsync(string authorizationCode, string redirectUri)
{
var tokenRequest = new AuthorizeRequest
{
GrantType = "authorization_code",
Code = authorizationCode,
RedirectUri = redirectUri,
ClientId = _oktaClient.Configuration.ClientId,
ClientSecret = _oktaClient.Configuration.ClientSecret,
};
return await _oktaClient.GetOAuthTokensAsync(tokenRequest);
}
- This completes the login process, and you can now use the tokens to authenticate API requests or retrieve user info.
Verify the ID Token
- Once you have the ID token, verify its signature and claims. This step ensures that the token is authentic and has not expired.
public bool VerifyIdToken(string idToken)
{
var handler = new JwtSecurityTokenHandler();
var token = handler.ReadJwtToken(idToken);
// Perform validation checks on the token (e.g., signature and expiration)
return token.ValidTo > DateTime.UtcNow;
}
- Use libraries such as `System.IdentityModel.Tokens.Jwt` and `Microsoft.IdentityModel.Tokens` to validate the token signature and claims.
Logout Implementation
- To log out the user, redirect them to the Okta sign-out URL, which terminates the session within Okta.
public string GetLogoutUrl()
{
return $"{_oktaClient.Configuration.OrgUrl}/oauth2/default/v1/logout?id_token_hint={idToken}&post_logout_redirect_uri={yourLogoutRedirectUri}";
}
- Ensure the ID token is valid and the post-logout redirect URI is configured in your Okta application settings.
By following these steps, you will have a comprehensive implementation of Single Sign-On using the Okta API in C#. Adjust the configurations and implementations as needed based on your application's specific requirements and infrastructure.
