WPF application with Windows authentication

Question

I have a simple wpf client (few text boxes) that uploads some data to a web service. And I want to use windows authentication to go with my application.

I am checking in OnStartup of App.xaml, whether or not the user is authenticated. My question is around what is the meaning of Thread.CurrentPrincipal.Identity.IsAuthenticated.

I don't want my application to be used from outside my network as it is connecting to a web service and uploads data. But my assumption is as long as you run this application from inside any windows network the above mentioned property will always return true?

So how do I find out if the application is being run from inside my network. I don't think checking domain name or role name is any different, because I can always setup a domain and name it whatever I want. I don't want to prompt user for username or password of any sort.

How do you check Identity of user against a particular AD (AD might not be publically available). Basically the application should only works from my local network or through VPN.

Answer 1

var context = new PrincipalContext(ContextType.Domain, "DOMAINNAME");
var result = UserPrincipal.FindByIdentity(domainContext, IdentityType.SamAccountName, userName);

If the result is null, then the user does not exists in the AD domain.

You can also user DirectorySearcher class to query AD based on a filter criteria. This is more useful only if you would like to retrieve additional details about the user like contact, email address etc.