Tag: authentication

Silverlight 4–Out of Browser Authentication

One of the things that was very difficult to find, even in silverlight forums, was a way to know, in a simple way, what user is authenticated when a Silverlight 4 application is running Out-Of-Browser. I’ve found many information about using WCF, RIA, etc, buts it was not what I wanted. So, I investigated a little more about trying to find out how isolated was Silverlight from windows.

At first sight, Silverlight should act as flash, isolated  as possible from the OS, but when running in Windows (as out-of-browser, thank you Microsoft for this “Air” copy”), I should access windows stuff, since I’m exclusively running in Windows, so the isolated thing doesn’t matter anymore! Wrong! I can access only some windows stuff! The .NET framework for Silverlight it’s a little bit “small” in features!

My first try, was to connect to SharePoint using ClientContext from Sharepoint Client API for Silverlight (My application needs some SharePoint list items). When inside SharePoint I just ask about “who am I”, and SharePoint , running in a windows domain, should respond to me with the authenticated user! Was successful! But with some hick ups every time someone from systems staff changed IIS Windows Authentication configuration or some SharePoint tweaks. The problem: I want to run an application and I need to use a SharePoint just to ask about “Who I am”? Yes, you are right! As we say in Portugal, “A cannon to kill a fly”.

Since my Silverlight app its running out of browser I needed to find a way to use directly windows. I thinks it’s a logic thinking!

When a Silverlight App its running outside browser with Elevated Privileges it can access COM stuff! Well, with this “opening”, the sky it’s the limit!

Thanks to “dynamic” word from C# we can do this:

            using (dynamic ad = AutomationFactory.CreateObject("ADSystemInfo"))
            {
                var usernamedn = ad.UserName;
                var computernamedn = ad.ComputerName;
                var DomainDNSNamedn = ad.DomainShortName;

                string us = usernamedn.ToString();
                us = us.Substring(3, us.IndexOf(',') - 3);
                username = string.Format(@"{0}\{1}", DomainDNSNamedn, us);
            }

As you may see, I use a COM Object that returns Active Directory information, including the User logged in.  (OK, the format it’s the AD CN=xxx,CN=xxx, but I now we have a door to the windows, very useful!

Bad Behavior has blocked 93 access attempts in the last 7 days.

Hyper Smash