Manipulate Privileges In Managed Code Reliably, Securely, And Efficiently

摘要

Like many developers of managed code, I frequently interact with system internals. One day, while working on the managed access control list (ACL) class library for the Microsoft~®.NET Framework 2.0 (see my article in the November 2004 issue of MSDN~® Magazine at msdn.microsoft.com/msdnmag/issues/04/11/ AccessControlinNET), I had to implement support for changing a security descriptor on an object. In some situations, this operation requires enabling Take Ownership and Security privileges. I poked around and discovered that there was no existing support in the .NET Framework for performing this task. Simple enough, I thought—a P/Invoke of the AdjustToken-Privileges API, and I'd be on my way. Little did I know how complex this task would become. I quickly discarded my original implementation due to several critical flaws, and about a dozen iterations later, I bring you the story of one of the coolest system programming quests in my recent memory. This article contains two solutions to the problem: the first, simpler one, is tailored to the .NET Framework 1.1 and can be used today. The second solution incorporates several advanced features available only in the .NET Framework 2.0. Regardless of which version of the Framework you are developing for, and irrespective of whether you want to understand the many technical complexities of the implementation, the solution presented here is going to be a valuable addition to your programming toolbox.