[REQUEST] Server security system

-- This is a special table that holds the environment.
-- There is a tutorial on metatables here: http://lua-users.org/wiki/MetamethodsTutorial
local sandEnv = setmetatable({}, {__index = getfenv(), __metatable = {}})

local function banned() error("Cannot use this function", 2) end -- Use for disabled functions

-- Disable filesystem. I don''t know what you want to do but it is an example
sandEnv.loadfile = banned
sandEnv._G = sandEnv

local envs = setmetatable({sandEnv = true}, {__mode="k"})
function sandEnv.getfenv(arg)
local env
if type(arg) == "function" then
env = getfenv(arg)
elseif arg == 0 then -- 'Global'
return sandEnv
elseif arg ~= nil then
env = getfenv(arg + 1) -- Increment stack by one
else
env = getfenv(2)
end

-- If we have never created this environment
-- then it must be outside the sandbox
-- hence we can use it
if not envs[env] then
print(env, " is invalid using ", sandEnv)
return sandEnv
end

return env
end

function sandEnv.setfenv(arg, env)
envs[env] = true
if type(arg) == "function" then
return setfenv(arg, env)
else
return setfenv(arg + 1, env) -- Increment stack by one
end
end

setfenv(function()

print("PRINT")
local newEnv = getfenv(print)
--newEnv.loadfile('Scrap.lua')
print("CURRENT")
local current = getfenv()
print(current)

setfenv(function()
print("INTERNAL")
print(getfenv())
end, setmetatable({}, {__index = current}))()

end, sandEnv)()