Authentication and Authorization

Well, it's Halloween, and in between going to answer the doorbell, I'm still studying for my Microsoft .NET 70-536 exam.

Can't think of anything I'd rather be doing on Halloween than studying and writing code. :-)

Authentication and Authorization classes reside in the System.Security.Principal namespace.

The following classes and interfaces exist in this namespace:

• WindowsIdentity - Represents a Windows or AD user account.
• WindowsPrincipal - Provides access to a user's group memberships. From my study book, "You can use the WindowsPrincipal class to determine which groups a user is a member of. To query for built-in groups, pass to the WindowsPrincipal.IsInRole method a member of the System.Security.Principal.WindowsBuiltInRole".
• GenericIdentity - For simple, non-Microsoft directory service user account.
• GenericPrincipal - For simple, non-Microsoft directory service groups.
• IIdentity - For custom users.
• IPrincipal - For custom groups.
• WindowsBuiltInRole (enum) - local Windows groups that are common in NT, 2000, XP. Include: User, PowerUser, Administrator, Guest, AccountOperator, SystemOperator, PrintOperator, BackupOperator, and Replicator.

Here is sample code to get the current user's group memberships:

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using System; using System.Threading; using System.Security.Principal;   namespace IdentityPrincipal {     class Program     {         static void Main(string[] args)         {             WindowsIdentity currentIdentity = WindowsIdentity.GetCurrent();             Console.WriteLine("Current User: '{0}", currentIdentity.Name);               // Two ways to get the currentPrincipal.             // 1. Through the WindowsPrincipal constructor passing in currentIdentity.             //WindowsPrincipal currentPrincipal = new WindowsPrincipal(currentIdentity);               // 2. Through the Thread.CurrentPrincipal property (after setting the Principal Policy of the             // current domain.  For this sample program, we will use this method.             AppDomain.CurrentDomain.SetPrincipalPolicy(PrincipalPolicy.WindowsPrincipal);             WindowsPrincipal currentPrincipal = (WindowsPrincipal) Thread.CurrentPrincipal;                           if (currentPrincipal.IsInRole(WindowsBuiltInRole.User))             {                 Console.WriteLine("Current User is a User");             }             if (currentPrincipal.IsInRole(WindowsBuiltInRole.Guest))             {                 Console.WriteLine("Current User is a Guest");             }             if (currentPrincipal.IsInRole(WindowsBuiltInRole.PowerUser))             {                 Console.WriteLine("Current User is a Power User");             }             if (currentPrincipal.IsInRole(WindowsBuiltInRole.Administrator))             {                 Console.WriteLine("Current User is an Administrator");             }             Console.ReadKey();         }     } }