URL encoding # sharp to Durandal SPA - asp.net-mvc

I know it is not necessary to specify a login URL to a Durandal login page. But I wonder how to fix the following problem I'm facing to redirect a Authentication to a specific Durandal Page that has a Sharp sign (i.e. #).
public void ConfigureAuth(IAppBuilder app)
{
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
AuthenticationType = DefaultAuthenticationTypes.ApplicationCookie,
//LoginPath = new PathString("/" + HttpUtility.UrlDecode("#") + "/login")
LoginPath = new PathString("/#/login")
});
...
}
When I paste:
http://localhost/#/login
to a browser URL I can navigate to the login page without any problems. I can login and it is working fine.
Because I'm mixing MVC with SPA in some scenarios, when I add [Authorize] attribute to an MVC controller, then I will be redirected as expected to
http://localhost/%23/login?ReturnUrl=%2Fe
and I get the error:
Server Error in '/' Application.
The resource cannot be found.
Description: HTTP 404. The resource you are looking for (or one of its dependencies) could have been removed, had its name changed, or is temporarily unavailable. Please review the following URL and make sure that it is spelled correctly.
Requested URL: /#/login
how to use the # sign instead of %23 char encoding? or maybe I'm messing something else!!!
FYI:
My question is related to character encoding not something line this: Login page on different domain because I may face the same problem in other situations in the future.

As far as I know it isn't possible to use a # from the server. A possible solution could be to redirect the user from the shell in durandal.js when the user isn't authenticated.

I don't know if it is too late in the life cycle but you could try to catch the redirect in the global asax file in the Application_EndRequest event and fix the response. I have code like this to change the actionresult to a jsonresult that my js can work with so that when a user attempts to reach an MVC controller resource that I have protected via java script ajax I can handle it properly.
protected void Application_EndRequest()
{
var context = new HttpContextWrapper(this.Context);
// If we're an ajax request and forms authentication caused a 302,
// then we actually need to do a 401
if (FormsAuthentication.IsEnabled && context.Response.StatusCode == 302
&& context.Request.IsAjaxRequest())
{
var jsRet = new JSONFunctionResult<Boolean>();
if (this.Request.IsAuthenticated)
{
jsRet.Messages.Add(new JSONFunctionResultMessage()
{
Text = string.Format("You must have one of these roles to perform the operation: {0}", context.Response.Headers["RolesRequired"]),
Title = "Security Violation",
Type = (int)JSONFunctionResultMessageTypes.authorization
});
}
else
{
jsRet.Messages.Add(new JSONFunctionResultMessage()
{
Text = "You must be logged into to access this resource",
Title = "Security Violation",
Type = (int)JSONFunctionResultMessageTypes.authentication
});
}
jsRet.OperationStatus = JSONFunctionResultOperationStatus.error.ToString();
string jresponse = JsonConvert.SerializeObject(jsRet);
context.Response.Clear();
context.Response.StatusCode = 200;
context.Response.ContentType = "application/json";
context.Response.Write(jresponse);
}
}
In my code I check for a redirect and if forms auth is enabled and if the user is Authenticated and change the response accordingly. For your code you could maybe change the response to go to your correct login page?

Related

Aspnet core cookie [Authorize] not redirecting on ajax calls

In an asp.net core 3.1 web app with cookie-based authorization I have created a custom validator which executes on the cookie authorization's OnValidatePrincipal event. The validator does a few things, one of those is check in the backend if the user has been blocked. If the user has been blocked, The CookieValidatePrincipalContext.RejectPrincipal() method is executed and the user is signed out using the CookieValidatePrincipalContext.HttpContext.SignOutAsyn(...) method, as per the MS docs.
Here is the relevant code for the validator:
public static async Task ValidateAsync(CookieValidatePrincipalContext cookieValidatePrincipalContext)
{
var userPrincipal = cookieValidatePrincipalContext.Principal;
var userService = cookieValidatePrincipalContext.GetUserService();
var databaseUser = await userService.GetUserBySidAsync(userPrincipal.GetSidAsByteArray());
if (IsUserInvalidOrBlocked(databaseUser))
{
await RejectUser(cookieValidatePrincipalContext);
return;
}
else if (IsUserPrincipalOutdated(userPrincipal, databaseUser))
{
var updatedUserPrincipal = await CreateUpdatedUserPrincipal(userPrincipal, userService);
cookieValidatePrincipalContext.ReplacePrincipal(updatedUserPrincipal);
cookieValidatePrincipalContext.ShouldRenew = true;
}
}
private static bool IsUserInvalidOrBlocked(User user)
=> user is null || user.IsBlocked;
private static async Task RejectUser(CookieValidatePrincipalContext context)
{
context.RejectPrincipal();
await context.HttpContext.SignOutAsync(CookieAuthenticationDefaults.AuthenticationScheme);
}
And here is the setup for the cookie-based authorization:
services.AddAuthentication(CookieAuthenticationDefaults.AuthenticationScheme)
.AddCookie(co =>
{
co.LoginPath = #$"/{ControllerHelpers.GetControllerName<AuthenticationController>()}/{nameof(AuthenticationController.Login)}";
co.LogoutPath = #$"/{ControllerHelpers.GetControllerName<AuthenticationController>()}/{nameof(AuthenticationController.Logout)}";
co.ExpireTimeSpan = TimeSpan.FromDays(30);
co.Cookie.SameSite = SameSiteMode.Strict;
co.Cookie.Name = "GioBQADashboard";
co.Events = new CookieAuthenticationEvents
{
OnValidatePrincipal = UserPrincipalValidator.ValidateAsync
};
co.Validate();
});
This actually gets called and executed as expected and redirects the user to the login page when they navigate to a new page after having been blocked.
Most of the views have ajax calls to api methods that execute on a timer every 10 seconds. For those calls the credentials also get validated and the user gets signed out. However, after the user has been signed out, a popup asking for user credentials appears on the page:
If the user doesn't enter their credentials and navigate to another page, they get taken to the login page as expected.
If they do enter their credentials, they stay logged in, but their identity appears to be their windows identity...
What is going on here? What I would really want to achieve is for users to be taken to the login page for any request made after they have been signed out.
I have obviously misconfigured something, so that the cookie-based authorization doesn't work properly for ajax requests, but I cannot figure out what it is.
Or is it the Authorization attribute which does not work the way I'm expecting it to?
The code lines look good to me.
This login dialog seems to be the default one for Windows Authentication. Usually, it comes from the iisSettings within the launchSettings.json file. Within Visual Studio you'll find find the latter within your Project > Properties > launchSettings.json
There set the windowsAuthentication to false.
{
"iisSettings": {
"windowsAuthentication": false,
}
}

OWIN authentication middleware: logging off

OWIN beginner here. Please be patient...
I'm trying to build an OWIN authentication middleware which uses form posts to communicate with my external authentication provider. I've had some success with getting the authentication bits working. In other words, I can:
communicate with the remote provider through form post;
process the response returned by the remove provider
If everything is ok, I'm able to signal the default authentication provider
THis in turn gets picked up by the cookie middleware which ends up generating the authentication cookie
So far, so good. Now, what I'd like to know is how to handle a log off request. Currently, the controller will simply get the default authentication manager from the owin context and call its SingOut method. This does in fact end my current session (by removing the cookie), but it really does nothing to the existing "external" session.
So, here are my questions:
1. Is the authentication middleware also responsible for performing log off requests?
2. If that is the case, then can someone point me to some docs/examples of how it's done? I've found some links online which describe the logging in part, but haven't found anything about the log off process...
Thanks.
Luis
After some digging, I've managed to get everything working. I'll write a few tips that might help someone with similar problems in the future...
Regarding the first question, the answer is yes, you can delegate the logoff to the middleware. If you decide to do that, then your middleware handler should override the ApplyResponseGrantAsync method and check if there's a current revoke request. Here's some code that helps to illustrate the principle:
protected override async Task ApplyResponseGrantAsync() {
var revoke = Helper.LookupSignOut(Options.AuthenticationType,
Options.AuthenticationMode);
var shouldEndExternalSession = revoke != null;
if (!shouldEndExternalSession) {
return;
}
//more code here...
}
After checking if there's a revoke request, and if your external authentication provider is able to end the response through a redirect, then you can simply call the Response.Redirect method (don't forget to check for the existance of redirect - ex.: if you're using asp.net identity and MVC's automatically generated code, then the sign out will redirect you to the home page of your site).
In my scenario, things were a little more complicated because communication with my authentication provider was based of form posts (SAML2 messages with HTTP Post binding). I've started by trying to use Response.Write to inject the HTML with the autopostback form into the output buffer:
protected override async Task ApplyResponseGrantAsync() {
//previous code + setup removed
var htmlForm = BuildAndSubmitFormWithLogoutData(url,
Options.UrlInicioSessaoAutenticacaoGov);
Response.StatusCode = 200;
Response.ContentType = "text/html";
await Response.WriteAsync(htmlForm);
}
Unfortunately, it simply didn't work out. Not sure on why, but the browser insisted in redirecting the page to the URL defined by the Logoff's controller method (which was redirecting the page to its home page or '/'). I've even tried to remove the location HTTP header from within the ApplyResponseGrantAsync method, but it still ended up redirecting the user to the home page (instead of loading the predefined HTML I was writing).
I've ended up changing the redirect so that it gets handled by my middleware. Here's the final code I've ended up with in the ApplyResponseGrant method:
protected override async Task ApplyResponseGrantAsync() {
//previous code + setup removed
//setup urls for callbabk and correlation ids
var url = ...; //internal cb url that gets handled by this middleware
Response.Redirect(url);
}
This redirect forced me to change the InvokeAsync implementation so that it is now responsible for:
Checking for a new authentication session
Checking for the end of an existing authentication session (handle the logoff response from the external provider)
Checking if it should generate a new form post html message that ends the current session controlled by the external provider
Here's some pseudo code that tries to illustrate this:
public override async Task<bool> InvokeAsync() {
if (Options.InternalUrlForNewSession.HasValue &&
Options.InternalUrlForNewSession == Request.Path) {
return await HandleLoginReply(); /login response
}
if (Options.InternalUrlExternalSessionEnded.HasValue &&
Options.InternalUrlExternalSessionEnded == Request.Path) {
return await HandleLogoffReply();//logoff response
}
if (Options.InternalUrlForEndingSession.HasValue &&
Options.InternalUrlForEndingSession == Request.Path) {
return await HandleStartLogoutRequest(); //start logoff request
}
return false;
}
Yes, in the end, I've ended with an extra request, which IMO shouldn't be needed. Again, I might have missed something. If someone manages to get the ApplyResponseGrantAsync to return the auto submit post (instead of the redirect), please let me know how.
Thanks.

MVC Windows Authentication causing querystring too long error

I have an MVC web site that I’d like to modify so instead of using forms to log the user in, it picks up their windows id then passes this to a local Active Directory using LDAP.
However, when I change IIS from Anonymous to Windows Authentication and change the code in Start.Auth.cs with the following (where LoginUser is the script that picks up the user and connects to AD)…
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
AuthenticationType = DefaultAuthenticationTypes.ApplicationCookie,
LoginPath = new PathString("/Account/LoginUser")
});
…it causes a querystring is too long browser error …
http://localhost:80/UserAuthentication/Account/LoginUser?ReturnUrl=%2FUserAuthentication%2FAccount%2FLoginUser%3FReturnUrl%3D%252FUserAuthentication%252FAccount%252FLoginUser%253FReturnUrl%253D%25252FUserAuthentication%25252FAccount%25252FLoginUser%25253FReturnUrl%25253D%2525252FUserAuthentication%2525252FAccount%2525252FLoginUser%2525253FReturnUrl%2525253D%252525252FUserAuthentication%252525252FAccount%252525252FLoginUser%252525253FReturnUrl%252525253D% (etc)
I have placed [AllowAnonymous] above the LoginUser script so I’m really not sure why it won’t go into it (as this what looks like is happening again and again).
Any help would really really be most appreciated.
Updated to include LoginUser script:
I've included a stripped down version of it that just logs a user in.
[AllowAnonymous]
public async Task<ActionResult> LoginUser()
{
var status = await SignInManager.PasswordSignInAsync("ATHORNE", "Something123!", false, false);
return View();
}
I am using PasswordSignInAsync with a constant password because there would not be a password for Windows Authentication. If there is a better way, please let me know!
The View is the blank default view at the moment.
Typically I would override OnActionExcuting(ActionExecutingContext filterContext)
You can do this in a base Controller class or in an Action Filter
If IIS is set to deny Anonymous Access and enable Windows authentication then within the filter context you can access the users' identity via HttpContext.User.Identity.Name;
To be a bit safer you could write some code like
var user = (filterContext.HttpContext.User.Identity != null
&& filterContext.HttpContext.User.Identity.IsAuthenticated) ?
HttpContext.User.Identity.Name : null;
If username is not null then you have the currently logged on authenticated user, in the form domain\username. You can query Active Directory based on this to get any other information you need.

With ASP.NET membership, how can I show a 403?

By default, ASP.NET's membership provider redirects to a loginUrl when a user is not authorized to access a protected page.
Is there a way to display a custom 403 error page without redirecting the user?
I'd like to avoid sending users to the login page and having the ReturnUrl query string in the address bar.
I'm using MVC (and the Authorize attribute) if anyone has any MVC-specific advice.
Thanks!
I ended up just creating a custom Authorize class that returns my Forbidden view.
It works perfectly.
public class ForbiddenAuthorizeAttribute : AuthorizeAttribute
{
public override void OnAuthorization(AuthorizationContext filterContext)
{
if (filterContext == null)
{
throw new ArgumentNullException("filterContext");
}
if (AuthorizeCore(filterContext.HttpContext))
{
// ** IMPORTANT **
// Since we're performing authorization at the action level, the authorization code runs
// after the output caching module. In the worst case this could allow an authorized user
// to cause the page to be cached, then an unauthorized user would later be served the
// cached page. We work around this by telling proxies not to cache the sensitive page,
// then we hook our custom authorization code into the caching mechanism so that we have
// the final say on whether a page should be served from the cache.
HttpCachePolicyBase cachePolicy = filterContext.HttpContext.Response.Cache;
cachePolicy.SetProxyMaxAge(new TimeSpan(0));
cachePolicy.AddValidationCallback(CacheValidateHandler, null /* data */);
}
else
{
// auth failed, display 403 page
filterContext.HttpContext.Response.StatusCode = 403;
ViewResult forbiddenView = new ViewResult();
forbiddenView.ViewName = "Forbidden";
filterContext.Result = forbiddenView;
}
}
private void CacheValidateHandler(HttpContext context, object data, ref HttpValidationStatus validationStatus)
{
validationStatus = OnCacheAuthorization(new HttpContextWrapper(context));
}
}
Asp.net has had what I consider a bug in the formsauth handling of unauthenticated vs underauthenticated requests since 2.0.
After hacking around like everyone else for years I finally got fed up and fixed it. You may be able to use it out of the box but if not I am certain that with minor mods it will suit your needs.
be sure to report success or failure if you do decide to use it and I will update the article.
http://www.codeproject.com/Articles/39062/Salient-Web-Security-AccessControlModule.aspx

Why does AuthorizeAttribute redirect to the login page for authentication and authorization failures?

In ASP.NET MVC, you can mark up a controller method with AuthorizeAttribute, like this:
[Authorize(Roles = "CanDeleteTags")]
public void Delete(string tagName)
{
// ...
}
This means that, if the currently logged-in user is not in the "CanDeleteTags" role, the controller method will never be called.
Unfortunately, for failures, AuthorizeAttribute returns HttpUnauthorizedResult, which always returns HTTP status code 401. This causes a redirection to the login page.
If the user isn't logged in, this makes perfect sense. However, if the user is already logged in, but isn't in the required role, it's confusing to send them back to the login page.
It seems that AuthorizeAttribute conflates authentication and authorization.
This seems like a bit of an oversight in ASP.NET MVC, or am I missing something?
I've had to cook up a DemandRoleAttribute that separates the two. When the user isn't authenticated, it returns HTTP 401, sending them to the login page. When the user is logged in, but isn't in the required role, it creates a NotAuthorizedResult instead. Currently this redirects to an error page.
Surely I didn't have to do this?
When it was first developed, System.Web.Mvc.AuthorizeAttribute was doing the right thing -
older revisions of the HTTP specification used status code 401 for both "unauthorized" and "unauthenticated".
From the original specification:
If the request already included Authorization credentials, then the 401 response indicates that authorization has been refused for those credentials.
In fact, you can see the confusion right there - it uses the word "authorization" when it means "authentication". In everyday practice, however, it makes more sense to return a 403 Forbidden when the user is authenticated but not authorized. It's unlikely the user would have a second set of credentials that would give them access - bad user experience all around.
Consider most operating systems - when you attempt to read a file you don't have permission to access, you aren't shown a login screen!
Thankfully, the HTTP specifications were updated (June 2014) to remove the ambiguity.
From "Hyper Text Transport Protocol (HTTP/1.1): Authentication" (RFC 7235):
The 401 (Unauthorized) status code indicates that the request has not been applied because it lacks valid authentication credentials for the target resource.
From "Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content" (RFC 7231):
The 403 (Forbidden) status code indicates that the server understood the request but refuses to authorize it.
Interestingly enough, at the time ASP.NET MVC 1 was released the behavior of AuthorizeAttribute was correct. Now, the behavior is incorrect - the HTTP/1.1 specification was fixed.
Rather than attempt to change ASP.NET's login page redirects, it's easier just to fix the problem at the source. You can create a new attribute with the same name (AuthorizeAttribute) in your website's default namespace (this is very important) then the compiler will automatically pick it up instead of MVC's standard one. Of course, you could always give the attribute a new name if you'd rather take that approach.
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, Inherited = true, AllowMultiple = true)]
public class AuthorizeAttribute : System.Web.Mvc.AuthorizeAttribute
{
protected override void HandleUnauthorizedRequest(System.Web.Mvc.AuthorizationContext filterContext)
{
if (filterContext.HttpContext.Request.IsAuthenticated)
{
filterContext.Result = new System.Web.Mvc.HttpStatusCodeResult((int)System.Net.HttpStatusCode.Forbidden);
}
else
{
base.HandleUnauthorizedRequest(filterContext);
}
}
}
Add this to your Login Page_Load function:
// User was redirected here because of authorization section
if (User.Identity != null && User.Identity.IsAuthenticated)
Response.Redirect("Unauthorized.aspx");
When the user is redirected there but is already logged in, it shows the unauthorized page. If they are not logged in, it falls through and shows the login page.
I always thought this did make sense. If you're logged in and you try to hit a page that requires a role you don't have, you get forwarded to the login screen asking you to log in with a user who does have the role.
You might add logic to the login page that checks to see if the user is already authenticated. You could add a friendly message that explains why they've been bumbed back there again.
Unfortunately, you're dealing with the default behavior of ASP.NET forms authentication. There is a workaround (I haven't tried it) discussed here:
http://www.codeproject.com/KB/aspnet/Custon401Page.aspx
(It's not specific to MVC)
I think in most cases the best solution is to restrict access to unauthorized resources prior to the user trying to get there. By removing/graying out the link or button that might take them to this unauthorized page.
It probably would be nice to have an additional parameter on the attribute to specify where to redirect an unauthorized user. But in the meantime, I look at the AuthorizeAttribute as a safety net.
Try this in your in the Application_EndRequest handler of your Global.ascx file
if (HttpContext.Current.Response.Status.StartsWith("302") && HttpContext.Current.Request.Url.ToString().Contains("/<restricted_path>/"))
{
HttpContext.Current.Response.ClearContent();
Response.Redirect("~/AccessDenied.aspx");
}
If your using aspnetcore 2.0, use this:
using System;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Filters;
namespace Core
{
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, Inherited = true, AllowMultiple = true)]
public class AuthorizeApiAttribute : Microsoft.AspNetCore.Authorization.AuthorizeAttribute, IAuthorizationFilter
{
public void OnAuthorization(AuthorizationFilterContext context)
{
var user = context.HttpContext.User;
if (!user.Identity.IsAuthenticated)
{
context.Result = new UnauthorizedResult();
return;
}
}
}
}
In my case the problem was "HTTP specification used status code 401 for both "unauthorized" and "unauthenticated"". As ShadowChaser said.
This solution works for me:
if (User != null && User.Identity.IsAuthenticated && Response.StatusCode == 401)
{
//Do whatever
//In my case redirect to error page
Response.RedirectToRoute("Default", new { controller = "Home", action = "ErrorUnauthorized" });
}

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