ASP.NET MVC Roles Authorization - asp.net-mvc

I want to make the roles default for my controller class to "Administrators, Content Editors"
[Authorize(Roles = "Administrators, Content Editor")]
I've done this by adorning the controller with the attribute above. However, there is one action that I want to be available to all (namely "View"). How can I reset the Roles so that everyone (including completely unauthorized users) have access for this action.
Note: I know I could adorn every single action other action with the authorize attribute above but I don't want to have to do that all the time. I want all of the controllers actions to be unacessible by default so that if anyone adds an action they have to make a considered decision to make it available to the general public.

MVC4 has a new attribute exactly meant for this [AllowAnonymous]
[AllowAnonymous]
public ActionResult Register()
http://blogs.msdn.com/b/rickandy/archive/2012/03/23/securing-your-asp-net-mvc-4-app-and-the-new-allowanonymous-attribute.aspx

You can place the Authorize attribute on the action methods. Not just at the class level.
So, move the attribute from the controller class to just the action methods you want to secure.

The only solution I can think of so far is to create and register another controller so that I have one for anonymous access, and one for authorized access but that's not quite as elegant as I would have liked.

Related

What are filters in asp.net mvc

What are the filters in asp.net mvc, can any one explain clearly.
How to create a custom filters in asp.net mvc 4
[Authorize]
Public ActionResults Index()
{
return View()
};
In ASP.NET MVC, controllers define action methods that usually have a one-to-one relationship with possible user interactions, such as clicking a link or submitting a form. For example, when the user clicks a link, a request is routed to the designated controller, and the corresponding action method is called.
Sometimes you want to perform logic either before an action method is called or after an action method runs. To support this, ASP.NET MVC provides action filters. Action filters are custom attributes that provide a declarative means to add pre-action and post-action behavior to controller action methods.
Check Filters-and-Attributes-in-ASPNET-MVC
The filter attribute has the Order property which can be used to manage the orders. The order needs to be the order the business process to be followed. For example if HandleError attribute is given higher order than the Authorize attribute then even an unauthorized users will be getting application errors. It would be better saying "Please Login".

How do I set permissions for my CRUD?

I am learning ASP.NET MVC3, and I just created a controller for my Model/Context. However, anyone can navigate to these pages and use them. How can I set permissions for these pages?
AuthorizeAttribute will be your first line of defense. You can grant access based on group membership or username. Works a lot like Code Access Security / Principal Permission Attributes but isn't as hard to work with.
Example:
// Allow Everybody in
public ActionResult Index ()
{}
// Allow only Editors/Admin to post edits back to controller.
[HttpPost]
[Authorize(Roles="Admin,Editor"]
public ActionResult Edit(EditViewModel vm)
{}
You can use them at the Class or Method Level, so you can have a base controller that only lets authorized users use certain controllers of your app.
If you find yourself using the same groups or users over and over, I would create an override of the AuthorizeAttribute that has those groups predefined, that way you don't misspell or forget them. This will also DRY up your code, which is always great.
You can use the Authorize attribute to rstrict permission, often this is inherited from the base class. This is the most common and recommended.
You can use the ActionFilter attribute and override the OnActionExecuting and set custom logic in there. Possible, but not the recommended.
There are lots of other ways too, but the prior two are the main ones for MVC.

I need to re route action based on some criteria

If a user is logged in and the ChangePasswordRequired flag is set, i need to disregard the current action and redirect them to the ChangePassword action.
In other words, I do not want the user to be able to do anything until he or she changes his or her password.
Which method should my base controller override and how should I handle the redirect?
You should create your own action filter.
The exact type of action filter you want to use is one that implements IAuthorizationFilter and the method you want to use it the OnAuthorizing() or close. This filter type is executed before all the others.
Instead of the [Authorize] filter you would use your own filter. Be sure to make your flag check and whether the user is authenticated (Request.IsAuthenticated)
Kindness,
Dan
I would use an actionfilter that you add to every controller class that should implement this behaviour. You can read some more on at this blog post by Phil Haack

Is it possible to override an attribute which has been applied at controller level on a specific method?

If I've applied an authorisation attribute at controller level, is it possible to override this on one of the methods on that controller?
Thanks
James
That depends upon what kind of "override" you want. You cannot remove the attribute which is on the class, but you can add the attribute to the method again in order to make things more restrictive.
Update in response to comments. First, making your own AuthorizeAttribute is somewhat dangerous. AuthorizeAttribute contains code which interacts with the caching attributes in order to ensure that the cache cannot serve protected content to a non-authorized user. At a minimum, you should subtype the existing AuthorizeAttribute rather than creating something wholly new. Generally, however, it's a better idea to use the existing AuthorizeAttribute and specialize your authorization by creating a new/finding an existing ASP.NET membership provider.
I don't think it would be good design to have a filter on an action which "overrides" a filter on a controller. However, you could change the design of the filter on the controller to not require authorization on an action of a certain name. You could, for example, override the AuthorizeAttribute.AuthorizeCore method to test for an action name in the same way the existing method tests for the user name and the roles. Take very careful note of the comments in this method regarding thread safety.
I'm not sure if this is exactly the same question, but it may help...
How to make ActionFilter on action method take precedence over same ActionFilter on controller

asp.net mvc newbie question

I recently started to look into asp.net mvc. Here is my issue.
Say every page on an application needs a variable set by the user, e.g. a date. If the user starts from url I provide, it is all good as I ask for that date and save it for the session. How can I redirect the user to the first page if they save the some other url (to a different controller and action).
In other words, I guess I am looking for something like [Authorize] attribute but on an application level.
Thanks for any help.
I would probably create a base controller that all of my controllers derive from. In the base controller I'd override the OnActionExecuting method to check the session for the required variable. If the variable isn't present, I would set the ActionExecutingContext Result property to a RedirectToRouteResult to the appropriate controller/action to set the variable.
Another alternative is to create a custom FilterAttribute that you decorate the appropriate controllers/actions with that does basically the same thing. I would only do this if the filter was to apply only to certain controllers or actions and not all as you describe in your question.

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