Develop Reference

Populating User.Identity in ASP.NET MVC 5

I'm writing a simple chat application using ASP.NET MVC 5 and SignalR. The application doesn't require any complicated authentication logic. User simply enters their login and enters the system (if there was no such user in the db before, it's created).
My intent was to use Session to hold the logged in user and their information (id from the database and login/username) and write a global filter to check if user is authenticated on each request. I've got some problems with SignalR though. It's not possible to access the Session from the SignalR Hub, while I need it to find out the login of the user who sent the message.
As fas as I found out, it's possible to work with the User.Identity using SignalR's Context. However, in my case Uder.Identity is completely empty. Presumably because I've created the app as 'no authentication' and the mechanism that User.Identity uses to get user data is not aware of my manipulation with session.
The question is, is it possible to elegantly intergate User.Identity into my application and make it aware of the Session? Creating ASP.NET MVC project with individual user accounts creates a mess with stuff like
public AccountController() :
this(new UserManager<ApplicationUser>(new UserStore<ApplicationUser>(new ApplicationDbContext())))
{
}
and that's what I don't want to have in my application by any means, since I want to write it as clean as possible and not use any solutions I am not familiar with. I also don't need any external login providers, cookies, etc.
I was thinking about implementing some in-memory storage on my own. However, I would still have to clean this store up at some point of time. I though of cleaning it up when the Session_End event is fired. However, this event will only be fired if there is data in Session which I don't want to have since it would be quite awkward to have standalone in-memory storage and rely on Session events to clean it up and, moreover, to set some data in Session just to make sure Session_End will fire.

Here's the solution I came up with. It's still not as clear as I would like it to be and it uses cookies, so any additions are welcome.
First of all, I had to install Microsoft.AspNet.Identity.Owin package and all its dependencies.
Then I registered my auth as follows:
private void ConfigureAuth(IAppBuilder app)
{
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
AuthenticationType = DefaultAuthenticationTypes.ApplicationCookie,
LoginPath = new PathString("/Account/Login")
});
}
This method is then called in Configuration method of Startup.cs file.
In order to work with the authentication, an instance of IAuthenticationManager is required. I inject it into my controller and use Ninject to resolve the dependency
kernel.Bind<IAuthenticationManager>().ToMethod(_ => HttpContext.Current.GetOwinContext().Authentication).InRequestScope();
Here's the Login method of Account controller which user is redirected to when auth is required (thanks to LoginPath in ConfigureAuth method):
[HttpPost]
public ActionResult Login(LoginViewModel model)
{
if (!ModelState.IsValid)
{
return View(model);
}
var user = authenticationService.AuthenticateUser(model.Login);
IdentitySignIn(user.Id, user.Login);
return RedirectToAction("Index", "Home");
}
AuthenticationService is my own class which communicates with the database and performs the login to create or return a user.
IdentitySignIn is declared as follows:
private void IdentitySignIn(int userId, string userLogin)
{
var claims = new List<Claim>();
claims.Add(new Claim(ClaimTypes.PrimarySid, userId.ToString()));
claims.Add(new Claim(ClaimTypes.Name, userLogin));
var identity = new ClaimsIdentity(claims, DefaultAuthenticationTypes.ApplicationCookie);
authenticationManager.SignIn(new AuthenticationProperties()
{
ExpiresUtc = DateTime.UtcNow.AddDays(200),
IsPersistent = true
}, identity);
}
This method creates a cookie with appropriate info. There is one thing, though. When I check the cookie expiration date, it's not the current date plus 200 days, which is kinda awkward.
SignOut method is quite simple:
public void IdentitySignout()
{
authenticationManager.SignOut(DefaultAuthenticationTypes.ApplicationCookie);
}
So, User.Identity is now accessible in the SignalR hub with the Identity.Name property.
To do: it would be also nice to get access to the Id property via something like User.Identity.Id. As far as I know, it requires implementing custom Principal.
I am also still thinking of implementing some sort of session of my own using cookies to store the session id on client side, though it will definitely take more time than using Identity.
Addition:
in order to get user id, one might use the extension method of IdentityExtensions:
(Inside the Hub)
Context.User.Identity.GetUserId()
In order for this to work, the Claim with the value of user's id should have the type ClaimTypes.NameIdentifier.
var claims = new List<Claim>();
claims.Add(new Claim(ClaimTypes.NameIdentifier, userId.ToString()));
claims.Add(new Claim(ClaimTypes.Name, userLogin));
Update 2:
Here are some additional links on the subject that greatly helped me. I do not include links to MS guides since they are quite easy to find.
http://leastprivilege.com/2015/07/21/the-state-of-security-in-asp-net-5-and-mvc-6-claims-authentication/
http://weblog.west-wind.com/posts/2015/Apr/29/Adding-minimal-OWIN-Identity-Authentication-to-an-Existing-ASPNET-MVC-Application

ASP.NET Web Api Authentication Methods

I am trying to implement authentication for my web api.
I have read about different techniques of api authentication and the token technique is the most reasonable for me.
I read different articles about how to implement token based authentication in asp.net but they all rely on different libraries such as OAuth or Owin which also provide their own method of database interactions.
The thing is that I have already implemented database interaction with abstract repositories and entities and I would like to find out how can I implement api authentication easily and simply without interfering with my current design.
(By the way, my project is built on top of an empty web api project, so it doesn't come with all the bootstrap and authentication classes).
Thank you

One solution I've seen is to use .NET's HttpApplicationState class and store tokens in appstate; this way you're not directly messing with Session (which would be a REST antipattern), but you can still track all currently logged in users and use HttpContext/HttpActionContext to x-ref active tokens in the app. The benefit to using HttpActionContext is that it is thread-safe, whereas HttpContext is not, so you can lock the appstate, mess with the HttpContext of an individual request, and then unlock the appstate to allow other threads in.
Since locking/unlocking appstate does tie up the app, I'm not sure how well this solution scales, but here it is anyway . . .
General outline:
When a user first logs in, a token is generated for him/her and stored in appstate. Then you can tag any API calls that require authentication (or that need other information stored on that user) with a custom attribute that checks for that token in the appstate, sending the token name as a header in the API call (e.g. "{token-name: TOKEN}").
Here's a brief example:
[in Controller method first activated at login:]
CustomUserObject user = new CustomUserObject();
//store user props
string token = Guid.NewGuid().ToString();
//create AppState instance, mine's called _appState
//...
_appState.Lock();
_appState[token] = user;
_appState.UnLock();
//...
[Then in global.asax:]
public class CustomAuthorize : System.Web.Http.AuthorizeAttribute
{
HttpRequestMessage request = actionContext.ControllerContext.Request;
string token = string.Empty;
if (request.Headers.GetValues("token-name") != null)
{
token = request.Headers.GetValues("token-name").FirstOrDefault().ToString();
IAppStateService appService; //<--- I've created a custom service tier class for appstate stuff
//Get appState instance, however makes sense for you.
//I'm using repo pattern with UnitOfWork, so mine looks like this...
//"IContainer ioc = DependencyResolution.IoC.Initialize();"
//"IAppStateService appService = ioc.GetInstance<IAppStateService>();"
appService.SetHttpApplicationState(HttpContext.Current.Application);
bool isAuthorized = appService.CheckTokenAndDoStuff(token);
//inside that method ^^^ you'll do stuff like
//"_appState.Lock();"
//"if (_appState[token] == null) return false" (or whatever)
//"_appState.Unlock();"
}
if (isAuthorized)
{
HttpResponseMessage resp = request.CreateResponse(HttpStatusCode.OK);
resp.Headers.Add("AuthenticationToken", token);
resp.Headers.Add("WWW-Authenticate", "Basic");
resp.Headers.Add("AuthenticationStatus", "Authorized");
}
return isAuthorized;
}
[then in webapi]
[HttpPost]
[CustomAuthorize]
public HttpResponseMessage NameOfMethod(...)...
...and that should x-check your appstate for your user token for you. Just make sure to include your token in your request header, and make sure to include the Basic Auth info in your response header.

Login page on different domain

I am completely new to OWIN authentication, and I must be misunderstanding how everything works, but I can't find this mentioned anywhere.
All I want is to be able to use a central domain for authentication. If someone tries to access apps.domain.com when not authenticated, they will be redirected to accounts.domain.com/login so that all the authentication is separated into it's own domain and application. This was very easy with MVC 4 forms authentication where you can specify a full URL, but doesn't seem to be with OWIN.
In Startup.Auth.cs:
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
LoginPath = new PathString("/account/login")
}
It's easy to specify the domain when setting the cookie with the CookieDomain option. However, when you specify the login path to redirect to, it has to be relative to the current application, so how do I go about accomplishing what was so easy in MVC 4 forms authentication?
Without getting too deep into what OWIN authentication is all about, I could not find anything addressing this after a couple hours of searching.

public class Startup
{
public void Configuration(IAppBuilder app)
{
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
AuthenticationMode = AuthenticationMode.Active,
LoginPath = new PathString("/account/login"),
LogoutPath = new PathString("/account/logout"),
Provider = new CookieAuthenticationProvider
{
OnApplyRedirect = ApplyRedirect
},
});
}
private static void ApplyRedirect(CookieApplyRedirectContext context)
{
Uri absoluteUri;
if (Uri.TryCreate(context.RedirectUri, UriKind.Absolute, out absoluteUri))
{
var path = PathString.FromUriComponent(absoluteUri);
if (path == context.OwinContext.Request.PathBase + context.Options.LoginPath)
{
context.RedirectUri = "http://accounts.domain.com/login" +
new QueryString(
context.Options.ReturnUrlParameter,
context.Request.Uri.AbsoluteUri);
}
}
context.Response.Redirect(context.RedirectUri);
}
}
If apps.domain.com is the only return URL base possible, you should strongly consider replacing context.Request.Uri.AbsoluteUri with context.Request.PathBase + context.Request.Path + context.Request.QueryString and build an absolute return URL in your authentication server to protect your apps from abusive redirects.
Hope this helps ;)
EDIT: you might ask yourself why I don't directly apply the redirect using the context.RedirectUri property. In fact, ICookieAuthenticationProvider.ApplyRedirect is responsible of multiple redirects, corresponding to the log-in and log-out flows (yep, I know, it breaks the single responsibility principle...). But there's even worse: context.RedirectUri can either represent the authentication endpoint's absolute URL in the beginning of the log-in flow or the final browser's destination (ie. the real relative "return URL") when the cookie is effectively being sent back to the browser... that's why we need to make sure that context.RedirectUri is absolute and corresponds to the registered context.Options.LoginPath.

I am working through the examples for https://github.com/IdentityServer/IdentityServer3 and I have a different answer. In the example at https://www.scottbrady91.com/Identity-Server/Identity-Server-3-Standalone-Implementation-Part-2 they show an MVC app that uses a standalone IdP and cookies authentication. The example hasn't included getting 401 redirects working, but I stumbled on a way.
The basic scheme is to create an action in the AccountController for logging on.
public ActionResult SignIn() {
// set up some bookkeeping and construct the URL to the central auth service
return Redirect(authURL);
}
Now you have a local URL that can be used in the Startup
public class Startup {
public void Configuration(IAppBuilder app) {
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
AuthenticationType = "Cookies",
LoginPath = new PathString("/Account/SignIn")
});
}
You also have the added benefit that you can put an action link to the SignIn on the menu bar, for people who want to log on before there is a 401. What we've done here is decoupled the decision of what to do when an unathenticated user asks for a resource from how the authentication is obtained.

ServiceStack Authorization - Access Route Information

In the documentation for ServiceStack, it says that the best practice is:
Normally ServiceStack calls the method bool HasPermission(string
permission) in IAuthSession. This method checks if the list
List Permissions in IAuthSession contains the required
permission.
IAuthSession is stored in a cache client as explained above You can
fill this list in the method OnAuthenticated you've overriden in the
first part of this tutorial.
I am integrating with an existing system, and have my custom BasicAuthProvider working (inherited from the base BasicAuthProvider). Authentication is working perfectly, now I am building out the Authorization portion. I plan on using the Permissions list as listed above, but I need access to the Route information to determine if a user has access to a particular resource. I see in the IAuthServiceBase there is an IRequestContext which has the absolute URL, but before going through and parsing that out, I figured there has to be a way to gain access to the ServiceStack Route structure to give me either the class name of the Service being requested, or the DTO the requested service is related to.
Here is the OnAuthenticated method from my BasicAuthProvider class:
public override void OnAuthenticated(IServiceBase authService, IAuthSession session, IOAuthTokens tokens, Dictionary<string, string> authInfo)
{
UserSession sess = (UserSession)session;
Model.User currentUser = UserRepository.GetUserByUsername(session.UserAuthName);
//Fill the IAuthSession with data which you want to retrieve in the app eg:
session.FirstName = currentUser.Person.FirstName;
session.LastName = currentUser.Person.LastName;
session.UserName = currentUser.User1;
sess.CurrentUser = currentUser;
//Important: You need to save the session!
authService.SaveSession(session, TimeSpan.FromDays(1));
}
Under MVC I have used some of the Raw Request Data to get the Controller and Action name before, to determine resource authorization, but this is the first project I am using ServiceStack with.

You may find the [RequiredPermission] attribute or even the implementation of it will help you, e.g. the 3rd parameter passed in a RequestFilter is the Request DTO.
And since a Request DTO maps 1:1 with the service, you can be sure that the request is destined for the IService<TRequest> (or its subclasses e.g. ServiceBase<T>, RestServiceBase<T>).
You can access the type of the service programatically as done in the FilterAttributeCache:
var serviceType = EndpointHost.Metadata.GetServiceTypeByRequest(requestDtoType);
I'm not sure of the exact context/use-case you're trying to support but using the [RequiredPermission] or [RequiredRole] attributes may have what you need which by default validates against the list of roles and permissions available in the built-in UserAuth table.
Externally you can use the /assignroles and /unassignroles web services (as part of the AuthorizationFeature plugin) to assign roles and permissions to users (it requires a user with the Admin role by default).
For more info see the documentation pages on Authentication/Authorization and Validation on the ServiceStack GitHub project wiki.

ASP.NET User Authentication across multiple projects

I am building an ASP.NET UI on an existing system, which consists of separate SQL server databases for each project. An "enterprise" database lists all current projects which allows anonymous users to select the project to work in. The project name is stored in a session variable. When log in is required the username/password/roles etc are obtained from the database indicated by the project name. I have implemented my own basic membership and role providers to do this, with changes in web.config to specify the roles required for specific pages. (I do not use the standard ASP.NET Configuration tool to manage users, I have existing apps that work with my user tables).
This all seemed to work initially but I discovered that the session variables are not yet loaded at the time when the authorization system checks the roles the current user belongs to in order to determine if the page is accessible. So if we have a < allow roles="xxx" > in web.config then the authorization system fires before session data is loaded and thus before I know which project database should be used.
[Specifically: HttpContext.Current.Session is null when the call to RoleProvider.GetRolesForUser is made]
Anybody who has tackled this problem should know exactly what I'm talking about. My questions therefore are:
A) What is the "Best Practise" solution to this scenario?
B) Could I be storing the project name somewhere else (not in session variable) that is available during the authorization phase?
[Update: Yes - we can use cookies, assuming we do not require cookieless operation]
C) Is there a way to manually get the session variable at this earlier time?
I tried an option to cache roles in cookies, but after a few minutes of testing with that option on I found GetRolesForUsers was still being called.
Thanks
Update:
Here is another description of the root problem which suggests "The application could cache this information in the Cache or Application objects.":
http://connect.microsoft.com/VisualStudio/feedback/details/104452/session-is-null-in-call-to-getrolesforuser
Update:
This looks like the same problem found here:
Extending the RoleProvider GetRolesForUser()
Update:
There was a suggestion about using UserData in FormsAuthenticationTicket, but I require this data even when not logged on.

UPDATE: I solve this these days in a much simpler way by using a wildcard SSL certificate that allows me to configure subdomains for each project, thus the project selection is specified directly in the URL (and each project gets its own subdomain). I still use a cookie hack purely for testing purposes when running on localhost where we have no subdomains.
Original solution:
I have not found any "best practise" write up on this scenario, but here is what I have settled on:
1) In order to support anonymous users switching between projects (i.e. SQL databases) I simply use a session variable to track the project selection. I have a global property that uses this project selection to serve the corresponding SQL connection string as and when it is required.
2) In order to support the call to GetRolesForUser() on pages that have role restrictions applied to them we cannot use the session variable, because as stated the session variable has not been initialized yet when GetRolesForUser() is actually called (and I have found no way to force it into being at this early point in the request cycle).
3) The only option is to use a cookie, or use the Forms Authentication ticket's UserData field. I trawled through many theories about using session/cookie/IDs linked to an object stored in the application cache (which is available when the session is not) but ultimately the correct choice is to place this data in the authentication ticket.
4) If a user is logged on to a project it is via a ProjectName/UserName pair, hence anywhere we are tracking the user's authentication we require both these data. In trivial testing we can get away with the username in the ticket and the projectname in a separate cookie, however it is possible for these to get out of synch. For example if we use a session cookie for the projectname and tick "remember me" when we logon (creating a permanent cookie for the authentication ticket) then we can end up with a username but no projectname when the session cookie expires (browser is closed). Hence I manually add the project name to the UserData field of the authentication ticket.
5) I have not figured out how to manipulate the UserData field without explicitly setting a cookie, which means that my solution cannot work in "cookieless" session mode.
The final code turned out to be relatively simple.
I override the Authenticate event of the LoginView in the login page:
//
// Add project name as UserData to the authentication ticket.
// This is especially important regarding the "Remembe Me" cookie - when the authentication
// is remembered we need to know the project and user name, otherwise we end up trying to
// use the default project instead of the one the user actually logged on to.
//
// http://msdn.microsoft.com/en-us/library/kybcs83h.aspx
// http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.login.remembermeset(v=vs.100).aspx
// http://www.hanselman.com/blog/AccessingTheASPNETFormsAuthenticationTimeoutValue.aspx
// http://www.csharpaspnetarticles.com/2009/02/formsauthentication-ticket-roles-aspnet.html
// http://www.hanselman.com/blog/HowToGetCookielessFormsAuthenticationToWorkWithSelfissuedFormsAuthenticationTicketsAndCustomUserData.aspx
// http://stackoverflow.com/questions/262636/cant-set-formsauthenicationticket-userdata-in-cookieless-mode
//
protected void LoginUser_Authenticate(object sender, AuthenticateEventArgs e)
{
string userName = LoginUser.UserName;
string password = LoginUser.Password;
bool rememberMe = LoginUser.RememberMeSet;
if ( [ValidateUser(userName, password)] )
{
// Create the Forms Authentication Ticket
FormsAuthenticationTicket ticket = new FormsAuthenticationTicket(
1,
userName,
DateTime.Now,
DateTime.Now.AddMinutes(FormsAuthentication.Timeout.TotalMinutes),
rememberMe,
[ ProjectName ],
FormsAuthentication.FormsCookiePath);
// Create the encrypted cookie
HttpCookie cookie = new HttpCookie(FormsAuthentication.FormsCookieName, FormsAuthentication.Encrypt(ticket));
if (rememberMe)
cookie.Expires = DateTime.Now.AddMinutes(FormsAuthentication.Timeout.TotalMinutes);
// Add the cookie to user browser
Response.Cookies.Set(cookie);
// Redirect back to original URL
// Note: the parameters to GetRedirectUrl are ignored/irrelevant
Response.Redirect(FormsAuthentication.GetRedirectUrl(userName, rememberMe));
}
}
I have this global method to return the project name:
/// <summary>
/// SQL Server database name of the currently selected project.
/// This name is merged into the connection string in EventConnectionString.
/// </summary>
public static string ProjectName
{
get
{
String _ProjectName = null;
// See if we have it already
if (HttpContext.Current.Items["ProjectName"] != null)
{
_ProjectName = (String)HttpContext.Current.Items["ProjectName"];
}
// Only have to do this once in each request
if (String.IsNullOrEmpty(_ProjectName))
{
// Do we have it in the authentication ticket?
if (HttpContext.Current.User != null)
{
if (HttpContext.Current.User.Identity.IsAuthenticated)
{
if (HttpContext.Current.User.Identity is FormsIdentity)
{
FormsIdentity identity = (FormsIdentity)HttpContext.Current.User.Identity;
FormsAuthenticationTicket ticket = identity.Ticket;
_ProjectName = ticket.UserData;
}
}
}
// Do we have it in the session (user not logged in yet)
if (String.IsNullOrEmpty(_ProjectName))
{
if (HttpContext.Current.Session != null)
{
_ProjectName = (string)HttpContext.Current.Session["ProjectName"];
}
}
// Default to the test project
if (String.IsNullOrEmpty(_ProjectName))
{
_ProjectName = "Test_Project";
}
// Place it in current items so we do not have to figure it out again
HttpContext.Current.Items["ProjectName"] = _ProjectName;
}
return _ProjectName;
}
set
{
HttpContext.Current.Items["ProjectName"] = value;
if (HttpContext.Current.Session != null)
{
HttpContext.Current.Session["ProjectName"] = value;
}
}
}

Can't you postback the project selection to some page, add that selection to the session, then redirect to appropriate protected page, where auth will kick in and force login?
ASP.NET session doesn't get created in the form of a cookie until you place at least one item in it.