adIdentity.cs

public class PutInGlobalAsaxCS {
    protected void Application_PostAuthenticateRequest()
    {
      var user = HttpContext.Current.User as WindowsPrincipal;
      if (user != null)
      {
        HttpContext.Current.User = new SpecPrincipal((WindowsIdentity) user.Identity);
      }
    }
  }

  public class SpecPrincipal : WindowsPrincipal
  {
    public SpecPrincipal(WindowsIdentity ntIdentity) : base(ntIdentity)
    {
    }

    public override bool IsInRole(string role)
    {
      var roleMgr = DependencyResolver.Current.GetService<ApplicationRoleManager>();
      var userMgr = DependencyResolver.Current.GetService<ApplicationUserManager>();
      var user = userMgr.GetCurrentUser();
      var rolesForUser = roleMgr.GetRolesForUser(user.Id);
      return rolesForUser.Select(r => r.Name).Contains(role);
    }
  }