How can I limit lua possibilities (calling OS functions, modules, etc.)

Question

I am using Lua as a script language inside my C application.

It suits me well, but I can't understand how can I limit Lua not to call system functions, include other modules, etc.

I want Lua to be able to call only functions that are allowed by me, because user can do all kind of bad things with full Lua + Lua modules power.

Answer 1

Take a look at the Simple Sandbox on the Lua-users wiki: http://lua-users.org/wiki/SandBoxes

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Answer 2

Sandbox is the term you're looking for. In a nutshell, only export to Lua the functions you want the users to call. It's that simple, really.