Can my linksys router receive unsecure wifi with firmware upgrades?

I have a few linksys routers laying around and i'm looking at DD-WRT upgrades yet nowhere is it telling me if i can use my router to receive unsecured wifi. Does anyone know?|||Almost all Linksys routers come from the factory with the ad-hoc capability. That is the best way to use it as a wireless range extender but has to be wired out to the computers.