c++ - UAC prompt elevation - how does it work?

Question

Windows displays UAC prompts on the "secure desktop" when certain security-related operations need to be performed. There's obviously some API somewhere that creates the secure desktop and creates a window on it, but I have no idea where I would find out about the mechanisms involved. I guess I could reverse engineer the UAC mechanisms, but I'm not that good at that level of reverse engineering (and I'm pretty sure there's some legal ramifications involved...)

Anyway, I know there's an API to create new desktops on the current session, but there's no mention of secure desktops in any documentation I can find. Out of curiosity, I'd like to know how the whole secure desktop / UAC prompt creation works.

Disclaimer: This is purely theoretical, and I'm not looking to deploy this in any of my code.

Answer 1

It seems likely that, from the point of view of the system, the secure desktop is just a perfectly normal desktop with a suitable ACL. Note that CreateDesktop allows you to specify a security descriptor for the new desktop.

So far as I know, the secure desktop has no special behaviour, so I see no reason to suppose that any additional API (documented or not) is involved.