Here I have simple private chat application in blazor server signalR where user logins, addfriend and chat with that friend.
For login I have used AspNetCore.Identity.
Now, the problem is that the application works perfectly fine in local machine but as I run application in ngrok() there is an error saying Error: System.Net.Http.HttpRequestException: Response status code does not indicate success: 401 (Unauthorized).ngrok is a cross-platform application that enables developers to expose a local development server to the Internet.
The software makes locally-hosted web server appear to be hosted on a subdomain of ngrok.com, meaning that no public IP or domain name on the local machine is needed
Below is what have done to authenticate user to signlar hub
In Host.cshtml
#{
var cookie = HttpContext.Request.Cookies[".AspNetCore.Identity.Application"];
}
<body>
#* Pass the captured Cookie to the App component as a paramter*#
<component type="typeof(App)" render-mode="Server" param-Cookie="cookie" />
</body>
In App.razor
#inject CookiesProvider CookiesProvider
#* code omitted here... *#
#code{
[Parameter]
public string Cookie { get; set; }
protected override Task OnInitializedAsync()
{
// Pass the Cookie parameter to the CookiesProvider service
// which is to be injected into the Chat component, and then
// passed to the Hub via the hub connection builder
CookiesProvider.Cookie = Cookie;
return base.OnInitializedAsync();
}
}
CookiesProvider.cs
public class CookiesProvider
{
public string Cookie { get; set; }
}
In webchat.razor
#attribute [Authorize]
#* code omitted here... *#
#code{
protected override async Task OnInitializedAsync()
{
var container = new CookieContainer();
var cookie = new Cookie()
{
Name = ".AspNetCore.Identity.Application",
Domain = "localhost",
Value = CookiesProvider.Cookie
};
container.Add(cookie);
hubConnection = new HubConnectionBuilder()
.WithUrl(NavigationManager.ToAbsoluteUri("/chathub"), options =>
{
// Pass the security cookie to the Hub.
options.Cookies = container;
}).Build();
await hubConnection.StartAsync();
}
}
In hub
[Authorize()]
public class ChatHub : Hub
{
}
Related
I have an application that authenticates using OpenId. The code in the startup is:
services.AddAuthentication(options =>
{
options.DefaultAuthenticateScheme = CookieAuthenticationDefaults.AuthenticationScheme;
options.DefaultSignInScheme = CookieAuthenticationDefaults.AuthenticationScheme;
options.DefaultChallengeScheme = CookieAuthenticationDefaults.AuthenticationScheme;
})
.AddCookie(options =>
{
options.LoginPath = new PathString("/account/login");
})
.AddOpenIdConnect("CustomScheme", options =>
{
// options configured
});
I have a hub and wire up the hub in the app.UseEndpoints as follows:
endpoints.MapHub<SpecialMessageHub>("myspecialhub");
Outside of posting my entire Startup.cs file, here is a quick overview:
app.UseAuthentication(); and app.UseAuthorization(); are before the app.UseEndpoints
services.AddSignalR(); and services.AddServerSideBlazor(); come after the services.AddAuthentication and services.AddAuthorization
I've simplified my Hub for this question:
using Example.Extensions;
using Example.Models;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.SignalR;
using System.Threading;
using System.Threading.Tasks;
namespace Example.Hubs
{
[Authorize]
public class SpecialMessageHub : Hub
{
public override Task OnConnectedAsync()
{
var customerId = Context.User.GetCustomerId();
Groups.AddToGroupAsync(Context.ConnectionId, GetCustomerGroupName(customerId));
return base.OnConnectedAsync();
}
public Task SendMessage(string customerId,
SpecialMessage message,
CancellationToken cancellationToken)
{
return Clients.Groups(GetCustomerGroupName(customerId)).SendAsync("ReceiveMessage", message, cancellationToken);
}
public static string GetCustomerGroupName(string customerId) => $"customers-{customerId}";
}
}
**Note: GetCustomerId is an extension method in my project
I have a simple component just to test this:
#page "/"
#using Microsoft.AspNetCore.SignalR.Client
#using Example.Models
#inject Microsoft.AspNetCore.Components.NavigationManager NavigationManager
#implements IAsyncDisposable
<h2>#myMessage.Id</h2>
<div>#myMessage.Message</div>
#code {
private HubConnection hubConnection;
private SpecialMessage myMessage = new SpecialMessage();
protected override async Task OnInitializedAsync()
{
if (!IsConnected)
{
hubConnection = new HubConnectionBuilder()
.WithUrl(NavigationManager.ToAbsoluteUri("/myspecialhub"))
.WithAutomaticReconnect()
.Build();
hubConnection.On<string, SpecialMessage>
("ReceiveMessage", (user, message) =>
{
myMessage = message;
StateHasChanged();
});
await hubConnection.StartAsync().ConfigureAwait(false);
}
}
public bool IsConnected => hubConnection != null
&& hubConnection.State == HubConnectionState.Connected;
public async ValueTask DisposeAsync()
{
await hubConnection?.DisposeAsync();
}
}
I then add that component into my view with the below:
<component type="typeof(SpecialMessageComponent)" render-mode="ServerPrerendered"/>
When I hit this view, it returns a 401:
Based on this https://learn.microsoft.com/en-us/aspnet/core/signalr/authn-and-authz?view=aspnetcore-3.1, the cookie should be passed to the hub:
In a browser-based app, cookie authentication allows your existing
user credentials to automatically flow to SignalR connections. When
using the browser client, no additional configuration is needed. If
the user is logged in to your app, the SignalR connection
automatically inherits this authentication.
I am able to verify the user is authenticated and has the claim I am looking for both in the controller and in the component. I feel like this should be fairly straightforward and wouldn't require multiple hops, so any help would be greatly appreciated.
Here are some of the things I have tried:
Pull both the "access_token" and "id_token" from the Context within the View and pass it to the component as a parameter. Then based on here https://learn.microsoft.com/en-us/aspnet/core/signalr/authn-and-authz?view=aspnetcore-3.1#bearer-token-authentication, I did something like this, but this still resulted in a 401:
[Parameter]
public string AccessToken { get; set; }
protected override async Task OnInitializedAsync()
{
if (!IsConnected)
{
hubConnection = new HubConnectionBuilder()
.WithUrl(NavigationManager.ToAbsoluteUri("/myspecialhub"), options =>
{
options.AccessTokenProvider = () => Task.FromResult(AccessToken);
})
.WithAutomaticReconnect()
.Build();
hubConnection.On<string, SpecialMessage>
("ReceiveMessage", (user, message) =>
{
myMessage = message;
StateHasChanged();
});
await hubConnection.StartAsync().ConfigureAwait(false);
}
}
}
I tried to manipulate the User by replacing the ClaimsPrincipal with a new IIdentity with the AuthenticationType set to CookieAuthenticationDefaults.AuthenticationScheme. This resulted in a nasty infinite loop but after restarting the app, the Identity was swapped, however, I still received a 401.
I have tried other options as well, but I cannot seem to get this to work with the OpenId.
In summary, the Blazor component is running on the server, so the HubConnection being made is from the server to the server.
await hubConnection.StartAsync().ConfigureAwait(false);
This establishes the server to server connection, which is why the HubCallerContext.User is not the user signed into the web application.
Personally, this was not intuitive to me. Because this is running on the server, there is not socket established with the browser. In order to accomplish this, one would have to use the Blazor WebAssembly to run the code on the client's browser. I've fallen back to handling this with JavaScript.
Here is the issue where Microsoft answers why this is not working: https://github.com/dotnet/aspnetcore/issues/36421
Goal:
I would like to have a kind of landing page if the user is not logged in (basically all other pages should be locked without the need of the [Authorize] attribute on all pages).
Setup:
Blazor WASM
ASP.NET Hosted (with IdentityServer authorization)
Code:
I have rewritten the MainLayout.razor to redirect all not authorized requests to my redirect handler
<NotAuthorized>
<RedirectToLogin />
</NotAuthorized>
My RedirectToLogin.razor contains the landing page named Index.razor and the RemoteAuthenticatorView for auth requests
#inject NavigationManager Navigation
#using Microsoft.AspNetCore.Components.WebAssembly.Authentication
#if (!string.IsNullOrEmpty(action))
{
<RemoteAuthenticatorView Action="#action" />
}
else
{
<div>
Landing page...<br />
Login<br />
register
</div>
}
My RedirectToLogin.razor.cs does listen to location changes and forwards authentication request to the RemoteAuthenticatorView
public partial class RedirectToLogin : IDisposable
{
[CascadingParameter] private Task<AuthenticationState> AuthenticationStateTask { get; set; }
[Inject] private NavigationManager NavigationManager { get; set; }
string action = "";
protected override async Task OnInitializedAsync()
{
NavigationManager.LocationChanged += LocationChanged;
}
public void Dispose()
{
NavigationManager.LocationChanged -= LocationChanged;
}
async void LocationChanged(object sender, LocationChangedEventArgs e)
{
action = "";
var authenticationState = await AuthenticationStateTask;
if (authenticationState?.User?.Identity is not null)
{
var url = Navigation.ToBaseRelativePath(Navigation.Uri);
if (!authenticationState.User.Identity.IsAuthenticated)
{
if (url == "authentication/logged-out")
{
NavigationManager.NavigateTo("", true);
return;
}
if (url.Contains("authentication"))
{
var index = url.IndexOf("authentication") + 15;
if (url.Contains("?"))
action = url.Substring(index, url.IndexOf('?') - index);
else
action = url.Substring(index);
}
this.StateHasChanged();
}
}
}
}
The Problem:
The whole system works fine for basically all authentication requests with the exception of login callbacks.
Instead of loading the authorized view it still shows the landing page.
You need to refresh the page or click a second time on the login button to be redirected to the authorized view.
I tried to navigate the user manually on navigation change with login callback in url or when the user is authorized, but nothing seems to work.
Have you any idea why this behavior occurs and/or how this can be fixed?
Please comment if there's an easier way to accomplish my goal. I didn't find anything on the net and tried my best.
The problem is you are passing everything relating to authentication to this landing page. You need to have two separate pages for what you are trying to do, one landing page for unauthorized users and one for the authorized ones.
To change this, you'll need to update your Program.cs file and set the AuthenticationPaths under builder.Services.AddApiAuthorization. Here's an example:
builder.Services.AddApiAuthorization(options =>
{
options.AuthenticationPaths.LogInPath = "auth/login";
options.AuthenticationPaths.LogInCallbackPath = "auth/login-callback";
options.AuthenticationPaths.LogInFailedPath = "auth/login-failed";
options.AuthenticationPaths.LogOutPath = "auth/logout";
options.AuthenticationPaths.LogOutCallbackPath = "auth/logout-callback";
options.AuthenticationPaths.LogOutFailedPath = "auth/logout-failed";
options.AuthenticationPaths.LogOutSucceededPath = "auth/logged-out";
options.AuthenticationPaths.ProfilePath = "auth/profile";
options.AuthenticationPaths.RegisterPath = "auth/register";
options.AuthenticationPaths.RemoteProfilePath = "/profile";
options.AuthenticationPaths.RemoteRegisterPath = "/register";
});
Then the Authentication.razor page:
#page "/auth/{action}"
#using Microsoft.AspNetCore.Components.WebAssembly.Authentication
<RemoteAuthenticatorView Action="#Action">
<LoggingIn></LoggingIn>
<CompletingLoggingIn></CompletingLoggingIn>
<LogInFailed>Failed to log in.</LogInFailed>
<LogOut></LogOut>
<LogOutFailed>Failed to log out.</LogOutFailed>
<CompletingLogOut></CompletingLogOut>
<LogOutSucceeded><RedirectToLogin ReturnUrl="Dashboard"/></LogOutSucceeded>
<UserProfile></UserProfile>
<Registering></Registering>
</RemoteAuthenticatorView>
#code{
[Parameter] public string Action { get; set; }
}
For more info on the RemoteAuthenticatorView, check out this Microsoft documentation: https://learn.microsoft.com/en-us/aspnet/core/blazor/security/webassembly/additional-scenarios?view=aspnetcore-5.0#customize-app-routes
and just below that section: https://learn.microsoft.com/en-us/aspnet/core/blazor/security/webassembly/additional-scenarios?view=aspnetcore-5.0#customize-the-authentication-user-interface
I have a simple .net core web api with angular app on the client side.
When I call my api locally (http://localhost:5000/api/auth/register) it works without any problems. After deploying app to azure and calling it (https://myapp.azurewebsites.net/api/auth/register), I get a 400 Bad Request error without any message.
I was trying to configure app service and sql server on azure portal but I'm not sure what to change.
AuthController.cs
[HttpPost("register")]
public async Task<IActionResult> Register(UserToRegisterDto userToRegister)
{
if (await AuthService.UserExists(userToRegister.UserName))
{
return BadRequest("Username already exists");
}
var userToCreate = new User() { UserName = userToRegister.UserName };
await AuthService.Register(userToCreate, userToRegister.Password);
// TODO: Change to return CreatedAtRoute
return StatusCode(201);
}
AuthService.cs
public async Task<User> Register(User user, string password)
{
GenerateHashedPassword(user, password);
await usersRepository.Create(user);
return user;
}
auth.service.ts
private baseUrl = environment.apiUrl + 'auth/';
public register(userToRegister: UserToRegister) {
return this.http.post(this.baseUrl + 'register', userToRegister);
}
environment.ts
export const environment = {
production: false,
apiUrl: 'http://localhost:5000/api/'
};
environment.prod.ts
export const environment = {
production: true,
apiUrl: 'api/'
};
First check your log in your azure web app there would be log when you accessing your web app
Second check exception capture in your azure web app any exeception occur will be capture with status code and the detail
Finally try to change your api url like this. But I dont think the error come from this setting
export const environment = {
production: true,
apiUrl: 'https://myapp.azurewebsites.net/api/'
};
Update to auto run migrate when you deploy new version in azure web app you can add these code snippet
public class Startup
{
...
public void ConfigureServices(IServiceCollection services)
{
services.AddDbContext<MyDbContext>(...);
...
}
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
UpdateDatabase(app);
...
}
private static void UpdateDatabase(IApplicationBuilder app)
{
using (var serviceScope = app.ApplicationServices
.GetRequiredService<IServiceScopeFactory>()
.CreateScope())
{
using (var context = serviceScope.ServiceProvider.GetService<MyDbContext>())
{
context.Database.Migrate();
}
}
}
}
I followed this tutorial: https://medium.com/#st.mas29/microsoft-blazor-web-api-with-jwt-authentication-part-1-f33a44abab9d
I downloaded the example: https://github.com/StuwiiDev/DotnetCoreJwtAuthentication/tree/Part2
I can see that the token is created but I don't understand how it is or should be saved on the client side as each time I access the SampleDataController, which has the Authorize tag, it returns a 401.
When calling and adding the token using Postman it works.
What am I missing for my user to be authenticated? Doesn't Microsoft.AspNetCore.Authentication.JwtBearer handle the client part (storing the token)?
What am I missing for my user to be authenticated? Doesn't Microsoft.AspNetCore.Authentication.JwtBearer handle the client part (storing the token)?
The JwtBearer runs on server side , it will only validate the authorization header of request, namely Authorization: Bearer your_access_token, and won't care about how you WebAssembly codes runs . So you need send the request with a jwt accessToken . Since the tutorial suggests you should use localStorage , let's store the accessToken with localStorage .
Because WebAssembly has no access to BOM yet, we need some javascript codes served as glue . To do that, add a helper.js under the JwtAuthentication.Client/wwwroot/js/ :
var wasmHelper = {};
wasmHelper.ACCESS_TOKEN_KEY ="__access_token__";
wasmHelper.saveAccessToken = function (tokenStr) {
localStorage.setItem(wasmHelper.ACCESS_TOKEN_KEY,tokenStr);
};
wasmHelper.getAccessToken = function () {
return localStorage.getItem(wasmHelper.ACCESS_TOKEN_KEY);
};
And reference the script in your JwtAuthentication.Client/wwwroot/index.html
<body>
<app>Loading...</app>
<script src="js/helper.js"></script>
<script src="_framework/blazor.webassembly.js"></script>
</body>
Now, let's wrap the javascript codes into C# . Create a new file Client/Services/TokenService.cs:
public class TokenService
{
public Task SaveAccessToken(string accessToken) {
return JSRuntime.Current.InvokeAsync<object>("wasmHelper.saveAccessToken",accessToken);
}
public Task<string> GetAccessToken() {
return JSRuntime.Current.InvokeAsync<string>("wasmHelper.getAccessToken");
}
}
Register this service by :
// file: Startup.cs
services.AddSingleton<TokenService>(myTokenService);
And now we can inject the TokenService into Login.cshtml and use it to save token :
#using JwtAuthentication.Client.Services
// ...
#page "/login"
// ...
#inject TokenService tokenService
// ...
#functions {
public string Email { get; set; } = "";
public string Password { get; set; } = "";
public string Token { get; set; } = "";
/// <summary>
/// response from server
/// </summary>
private class TokenResponse{
public string Token;
}
private async Task SubmitForm()
{
var vm = new TokenViewModel
{
Email = Email,
Password = Password
};
var response = await Http.PostJsonAsync<TokenResponse>("http://localhost:57778/api/Token", vm);
await tokenService.SaveAccessToken(response.Token);
}
}
Let's say you want to send data within FetchData.cshtml
#functions {
WeatherForecast[] forecasts;
protected override async Task OnInitAsync()
{
var token = await tokenService.GetAccessToken();
Http.DefaultRequestHeaders.Add("Authorization",String.Format("Bearer {0} ",token));
forecasts = await Http.GetJsonAsync<WeatherForecast[]>("api/SampleData/WeatherForecasts");
}
}
and the result will be :
Apologies in advance as this is somewhat responding to a previous answer, but I don't have the rep to comment on that.
If it helps anyone else who was similarly looking for a solution to using JWT in a Blazor app, I found #itminus answer incredibly useful, but it also pointed me to another course.
One problem I found was that calling FetchData.cshtml a second time would blow up when it tries to add the Authorization header a second time.
Instead of adding the default header there, I added it to the HttpClient singleton after a successful login (which I believe Blazor creates for you automatically). So changing SubmitForm in Login.cshtml from #itminus' answer.
protected async Task SubmitForm()
{
// Remove any existing Authorization headers
Http.DefaultRequestHeaders.Remove("Authorization");
TokenViewModel vm = new TokenViewModel()
{
Email = Email,
Password = Password
};
TokenResponse response = await Http.PostJsonAsync<TokenResponse>("api/Token/Login", vm);
// Now add the token to the Http singleton
Http.DefaultRequestHeaders.Add("Authorization", string.Format("Bearer {0} ", response.Token));
}
Then I realised, than as I'm building a SPA, so I didn't need to persist the token across requests at all - it's just in attached to the HttpClient.
The following class handle the login process on the client, storing the JWT token in local storage. Note: It is the developer responsibility to store the JWT token, and passes it to the server. The client (Blazor, Angular, etc.) does not do that for him automatically.
public class SignInManager
{
// Receive 'http' instance from DI
private readonly HttpClient http;
public SignInManager(HttpClient http)
{
this.http = http;
}
[Inject]
protected LocalStorage localStorage;
public bool IsAuthenticated()
{
var token = localStorage.GetItem<string>("token");
return (token != null);
}
public string getToken()
{
return localStorage.GetItem<string>("token");
}
public void Clear()
{
localStorage.Clear();
}
// model.Email, model.Password, model.RememberMe, lockoutOnFailure: false
public async Task<bool> PasswordSignInAsync(LoginViewModel model)
{
SearchInProgress = true;
NotifyStateChanged();
var result = await http.PostJsonAsync<Object>("/api/Account", model);
if (result)// result.Succeeded
{
_logger.LogInformation("User logged in.");
// Save the JWT token in the LocalStorage
// https://github.com/BlazorExtensions/Storage
await localStorage.SetItem<Object>("token", result);
// Returns true to indicate the user has been logged in and the JWT token
// is saved on the user browser
return true;
}
}
}
// This is how you call your Web API, sending it the JWT token for // the current user
public async Task<IList<Profile>> GetProfiles()
{
SearchInProgress = true;
NotifyStateChanged();
var token = signInManager.getToken();
if (token == null) {
throw new ArgumentNullException(nameof(AppState)); //"No token";
}
this.http.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
// .set('Content-Type', 'application/json')
// this.http.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
Profiles = await this.http.GetJsonAsync<Profile[]>("/api/Profiles");
SearchInProgress = false;
NotifyStateChanged();
}
// You also have to set the Startup class on the client as follows:
public void ConfigureServices(IServiceCollection services)
{
// Add Blazor.Extensions.Storage
// Both SessionStorage and LocalStorage are registered
// https://github.com/BlazorExtensions/Storage
**services.AddStorage();**
...
}
// Generally speaking this is what you've got to do on the client. // On the server, you've got to have a method, say in the Account controller, whose function is to generate the JWT token, you've to configure the JWT middleware, to annotate your controllers with the necessary attribute, as for instance:
[Authorize(AuthenticationSchemes = JwtBearerDefaults.AuthenticationScheme)]
and so on...
Hope this helps...
I am using a webapi project as my auth Server and also resource server. The intention is to access the serivice form an Android app. I also want a web front end which is being written in an MVC app. I originally used the default MVC auth but have moved to web pai handing out tokens. I can recieve the auth token form the webapi service and I am sending the token to the client in a cookie although I may just cache is client side. I currently have the following OAuthBearerAuthenticationProvider running:
public class CookieOAuthBearerProvider : OAuthBearerAuthenticationProvider
{
public override Task RequestToken(OAuthRequestTokenContext context)
{
base.RequestToken(context);
var value = context.Request.Cookies["AuthToken"];
if (!string.IsNullOrEmpty(value))
{
context.Token = value;
}
return Task.FromResult<object>(null);
}
}
and in my startup class I have this method:
private void ConfigureAuth(IAppBuilder app)
{
app.UseOAuthBearerAuthentication(new OAuthBearerAuthenticationOptions()
{
Provider = new CookieOAuthBearerProvider(),
});
}
which I call in the Configuration method.
The bit I seem to be missing is how to tap into converting my token into the logged in user. I cant seem to figure out where the deserializtion happens. I have tried changing my configueAuth to:
private void ConfigureAuth(IAppBuilder app)
{
app.UseOAuthBearerAuthentication(new OAuthBearerAuthenticationOptions()
{
Provider = new CookieOAuthBearerProvider(),
AccessTokenProvider = new AuthenticationTokenProvider()
{
OnReceive = receive
}
});
}
public static Action<AuthenticationTokenReceiveContext> receive = new Action<AuthenticationTokenReceiveContext>(c =>
{
c.DeserializeTicket(c.Token);
c.OwinContext.Environment["Properties"] = c.Ticket.Properties;
});
and my receive method is being called. The AuthenticationTokenReceiveContext has my token attached but the DeserializeTicket is returning null. Can anyone advise what I am missing to get the User details form this token?
UPDATE as per suggested answer below. The Statrup code and OAuthBearerAuthenticationOptions now like like this:
public class Startup
{
public void Configuration(IAppBuilder app)
{
ConfigureAuth(app);
AreaRegistration.RegisterAllAreas();
FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
RouteConfig.RegisterRoutes(RouteTable.Routes);
BundleConfig.RegisterBundles(BundleTable.Bundles);
}
private void ConfigureAuth(IAppBuilder app)
{
OAuthOpt = new OAuthBearerAuthenticationOptions()
{
Provider = new CookieOAuthBearerProvider(),
AccessTokenProvider = new AuthenticationTokenProvider()
{
OnReceive = receive
}
};
app.UseOAuthBearerAuthentication(OAuthOpt);
}
public static Action<AuthenticationTokenReceiveContext> receive = new Action<AuthenticationTokenReceiveContext>(c =>
{
var ticket = OAuthOpt.AccessTokenFormat.Unprotect(c.Token);
});
public static OAuthBearerAuthenticationOptions OAuthOpt { get; private set; }
}
but I am still getting a null value out. Could I be missing some relevant option on the OAuthBearerAuthenticationOptions?
Try this.
Save the OAuthBearerAuthenticationOptions you are instantiating inline to a static variable named OAuthOpt (or anything you like) in Startup.Auth and use the code below wherever you want to retrieve the user information.
Microsoft.Owin.Security.AuthenticationTicket ticket = Startup.OAuthOpt.AccessTokenFormat.Unprotect(token);`
I suggest you make use of Json Web Tokens (JWT) and customize the token generation using a CustomOAuthProvider. Here is a good resource from Taiseer Joudeh on how to do this. You will have to use this nuget package to decode the bearer tokens.