- Thank you!
16 hours 3 min ago - Lucky... should have never taken IB...
4 days 4 hours ago - awesome :)
1 week 2 days ago - Very nice!
1 week 6 days ago - What a nice job
3 weeks 6 days ago - Amazing work
5 weeks 3 days ago - Haskell is fun
6 weeks 1 day ago - Gotta love Brainfsck xD
6 weeks 1 day ago - help me plz
6 weeks 1 day ago - wxRibbon
7 weeks 6 days ago
Obfuscated Lua
Sun, 19 Apr 2009 - 12:09pm — Corsix
I like Lua as a programming language for its beauty and simplicity, but sometimes you have to defile a language with horribly obfuscated code:
L= {} for k,v
in next ,_G ._G
do L[#k ]=v end
L[10 ](([[p =prin t;for
'q=99, 1,-1'do' gg'q>1' th{n'p(
q.."'Bs' {f'!:::'{n 'th{'<114 ,'"..q.."
'Bs'of'!:: [.")gg'q>2't h{n's=(q-1) .."'Bs'{f'[
!::'{n'th{ '<!+$."{lse' s="1'B'{f'$ !::'{n'th{'
<onx."{nd; elsegg'q==1' then'p"1'B' {f'x!::'{n'
th{'wall,' 1'B'of'[!::. "s="no'mor{ '!::''{n'th
e'<'!4!"en d;p("Take'{n {'down,'pas s'it'around
,'"..s)p"- "{nd]]):gsub ("["..[==[$ 4[]==]..[[x
]].."]","" ):gsub([[B]] ,"bottle"): gsub("''?",
" "):gsub( "!:+","beer" ):gsub("gg" ,"if"):rep(
3-2):gsub( "<..","wall" ):gsub("{", function(_)
B=((B)or(3 ))+1;return( "eooe"):sub (B%4+1,(B+1
+2+9)%4+(# L[1]-13),(B* 2)%7)end))( L[#L]or...)Despite what it looks like, it is valid Lua 5.1 code. If it isn't immediately obvious what it does, then you can see the output.
The overall form of the code is loadstring(([[code]]):decrypt())(). Of course, putting a straight loadstring call into the code would make things obvious (and it would break the nice formatting). Hence there is this lovely piece of code instead:
L = {}
for key, value in pairs(_G) do
L[#key] = value
end
-- L[10] is now loadstring (and L[1] is L)This relies on the fact that loadstring is the only global variable whose name is 10 characters long:
| Length | Globals |
|---|---|
| 1 | L |
| 2 | _G os |
| 4 | load math type next |
| 5 | debug error pairs pcall print table |
| 6 | dofile ipairs module rawget rawset select string unpack xpcall |
| 7 | getfenv package require setfenv |
| 8 | _VERSION loadfile newproxy tostring |
| 9 | coroutine |
| 10 | loadstring |
| 12 | getmetatable setmetatable |
| 14 | collectgarbage |
Next comes a long string containing the true program code (although not in plaintext), and then after it come a number of calls to string.gsub to turn the string back into valid Lua code. The calls to gsub are:
| Pattern | Replacement |
|---|---|
| [$4[x%s] | (nothing) |
| B | bottle |
| ''? | (space) |
| !:+ | beer |
| gg | if |
| <.. | wall |
| { |
function()
B = (B or 3) + 1
return ("eooe"):sub((B % 4) + 1, (B % 4) + 1)
end |
After all of these replacements, the code that gets send to loadstring is: (linebreaks and indentation added for clarity)
p=print;
for q=99,1,-1 do
if q>1 then
p(q.." bottles of beer on the wall, "..q.." bottles of beer.")
if q>2 then
s=(q-1).." bottles of beer on the wall."
else
s="1 bottle of beer on the wall."
end;
elseif q==1 then
p"1 bottle of beer on the wall, 1 bottle of beer."
s="no more beer on the wall!"
end;
p("Take one down, pass it around, "..s)
p"-"
endThis code is loaded, and then executed, and the result is (obviously) the 99 bottles of beer song.
Comments
DoW DC modding
about the copying units thing, i cant just simply copy, paste. This is because whenever i add anything into the mod folder created by mod studio or if i made it myself, i cant load my mod, it just exits DoW DC. so how would i put new units in without making them from scratch?
DoW DC modding
im using your mod studio to mod DoW DC, and its so much easier than using relics mod tools, but i have a problem, i want to add new units to my mod, but they are also in the "annihilation mod", so i want to copy them from there and put them in my mod. How wud i go about doing this?
(please bear in mind i dont know very much about computers or modding)
Dude!
Well done! If only you could teach me how to do things like this haha. I've downloaded your studio to try messing around with CoH mods, but, because I'm mod challenged, I can barely figure out how to do anything. I couldn't even get my engineer squads to be 5 num with 6 max like the very first tutorial said. I tried everything I could think of to no avail :/. Great work though, in everything I've seen about you. I'm quite envious of your talent.
:)
That's cool :D
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