nGhost is open source,
RR is free
CF is neither free nor open source.
Open Source doesn't necessarily mean free as in cost. Free Open Source Software does however. Anything Open Source, once you obtain it either freely or by paying money for it, you are free to do with it as you like. That includes source code modification and all sorts of tweaking. Free Software while it doesn't cost anything, you aren't free to hack/tweak/modify any of the codes.
Obviously, closed non-free software is such that you pay to use, and aren't allowed to change.