slave.lua

--Version: 2.1
--[[
MIT License

Copyright (c) 2019 Caleb Serafin

Permission is hereby granted, free of charge, to any person obtaining a copy
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]]

----------------------Config----------------------
local addr=nil	--Provide the master's network card address
local port=2852	--Listen and send on this port
local dist=nil	--For restricting the maximium distance
local pass="P0r2DruPG7xokYqh"	--Should be the 2nd data packet
-------------------Declarations-------------------
--OpenOS hides these. This will allow component calls to be the same as for BIOS slaves.
_G.component = require("component")
_G.computer = require("computer")
_G.process = require("process")
_G.unicode = require("unicode")
local event = require("event")
local modem = component.modem
-----------------------Body-----------------------
modem.open(port)
--They are registered here to avoid being destroyed and created every loop.
local addrX,distX,cmdX,passX
local func, feedback
while true do
	_,_,addrX,_,distX,cmdX,passX=event.pull(math.huge, "modem_message")
	if not((addr and addrX~=addr)or(dist and distX>dist)or(passX~=pass))then
		func, feedback = load(cmdX)
		if func then --If there was a malformed func this will stop execution to avoid crashing the slave.
			_,feedback=pcall(func) 
		end
		modem.send(addrX, port, feedback, pass)	--This has to pass back to the orignal master to prevent sniffing.
	end
end