重定向未授权用户asp net

Question

I'm working on a simple website in asp.net. I would like to restric access to the side, so that only users in a specific AD group is allowed. I have done that and it is working fine. But when a user that's not in the AD group tries to access the site, they are getting a login prompt. How do I redirect the unauthorized user to a custom page, instead of they getting the login prompt?

Below is my web.config. The lowest part of the code, is something i tried but did not work.

<configuration>
<system.web>
  <compilation debug="true" targetFramework="4.0" />
  <authentication mode="Windows"/>
  <authorization>
    <allow roles="DOMAIN\GROUP"/>
    <deny users="*"/>
  </authorization>
</system.web>

<location path="AccessDenied.aspx">
<system.web>
<authorization>
  <allow users="*"/>
</authorization>
</system.web>
</location>
</configuration>

I have added this to the Global.asax.cs:

protected void Application_EndRequest(Object sender, EventArgs e)
    {
        if (HttpContext.Current.Response.Status.StartsWith("401"))
            {
                HttpContext.Current.Response.ClearContent();
                Server.Execute("AccessDenied.aspx");
            }
}

Any ideas ?

EDIT: I tried some of the posted solutions, but they did not work. But I got it working with this code:

void Application_EndRequest(object sender, System.EventArgs e)
    {
        if (((Response.StatusCode == 401)
        && (Request.IsAuthenticated == true)))
        {
            Response.ClearContent();
            Response.Redirect("~/AccessDenied.aspx");
        }
    }
}

Answer 1

You can use Response.Redirect or Server.Transfer

Response.Redirect("AccessDenied.aspx");

Full example:

protected void Application_EndRequest(Object sender, EventArgs e)
{
  if (HttpContext.Current.Response.Status.StartsWith("401"))
  {
      HttpContext.Current.Response.ClearContent();
      Response.Redirect("AccessDenied.aspx");
  }
}

Answer 2

Assuming you want to handle all "Unauthorized" errors:

<customErrors defaultRedirect="Error.aspx" mode="On">
    <error statusCode="401" redirect="Unauthorized.aspx" />
    <error statusCode="403" redirect="Forbidden.aspx" />
</customErrors>

Any 401 (unauthorized) requests will be forwarded to Unauthorized.aspx.

Answer 3

I had more success with this:

      // This is a workaround for the fact that we are not using MVC and its attributes
      // This is the situation where a user is logged in - but not authorized for this page
      void Application_EndRequest (object sender, System.EventArgs e)
      {
         if (((Response.StatusCode == 302) && (Request.IsAuthenticated == true)))
         {
            try
            {
               string sLoc = Response.Headers ["Location"];
               if (sLoc.Contains ("Login"))
               {
                  Response.ClearContent ();
                  Response.Redirect ("~/AccessDenied.aspx");
               }
            }
            catch
            {
            }
         }
      }

Answer 4

<authorization>
 <!--<allow users="*"/>-->This here means allow everyone .
 <allow users="AD"/> -- Add this group to AD domain .  
 <deny users="?"/> --Deny unknown users(Not authenticated)
 <allow roles="Admins"/> --If you have created roles .    

If you have local group than use <allow user ="AD"> but you have to register it to AD domain . <allow roles ="AD" /> will work only with Domain AD groups not for local groups .

 protected void Application_EndRequest(Object sender,EventArgs e) 

  { 
     HttpContext context = HttpContext.Current;
     if (context.Response.Status.Substring(0,3).Equals("401"))
     {
        context.Response.ClearContent();
         //do redirect here 
     } 
  }