Lua obfuscation issue - lua

I have tried to decompile one of Lua script just for learning purposes, and I got the original code however the code was obfuscated like below:
local L0_0, L1_1, L2_2, L3_3, L4_4, L5_5, L6_6, L7_7, L8_8, L9_9, L10_10, L11_11, L12_12, L13_13, L14_14, L15_15, L16_16, L17_17, L18_18, L19_19, L20_20, L21_21, L22_22, L23_23, L24_24, L25_25, L26_26, L27_27, L28_28, L29_29
L0_0 = require
L1_1 = "comm.NetworkClock"
L0_0 = L0_0(L1_1)
L1_1 = require
L2_2 = "comm_ads.fullscreenAds"
L1_1 = L1_1(L2_2)
L2_2 = require
L15_15 = L14_14.init
L15_15()
L15_15 = L4_4.log
L16_16 = "IN main"
L15_15(L16_16)
function L15_15()
local L0_30, L1_31
end
print = L15_15
Is there any way to recover these code to reach the original one?

Can you get back to the original source? No, not likely.
Source code is optimized to be read by humans, byte code is optimized to be read by machines. Compiling usually results in a one-way conversion where information required to restore the original source is lost.
Best bet at this point is to simplify it by hand and a bunch of find & replace once you identify what a variable or function actually does.
If you did find (or build) a tool to simplify the decompiled source code to be more human-readable, it still would not really be reproducing the original source code.

Related

How to find the file paths of all namespace loaded in an application using tcl/TK under Unix?

For existing flow, there would be a whole bunch of namespaces loaded when running some script job.
However, if I want to check & trace the usage of some command in some namespace, I need to find the script path of the certain namespace.
Is there some way to get that? Particularly, I'm talking about Primetime scripts.
Technically, namespaces don't have script paths. But we can do something close enough:
proc report_current_file {call code result op} {
if {$code == 0} {
# If the [proc] call was successful...
set cmd [lindex $call 1]
set qualified_cmd [uplevel 1 [list namespace which $cmd]]
set file [file normalize [info script]]
puts "Defined $qualified_cmd in $file"
}
}
trace add execution proc leave report_current_file
It's not perfect if you've got procedures creating procedures dynamically — the current file might be wrong — but that's fortunately not what most code does.
Another option that might work for you is to use tcl::unsupported::getbytecode, which produces a lot of information in machine-readable format (a dictionary). One of the pieces of information is the sourcefile key. Here's an example running interactively on my machine:
% parray tcl_platform
tcl_platform(byteOrder) = littleEndian
tcl_platform(engine) = Tcl
tcl_platform(machine) = x86_64
tcl_platform(os) = Darwin
tcl_platform(osVersion) = 20.2.0
tcl_platform(pathSeparator) = :
tcl_platform(platform) = unix
tcl_platform(pointerSize) = 8
tcl_platform(threaded) = 1
tcl_platform(user) = dkf
tcl_platform(wordSize) = 8
% dict get [tcl::unsupported::getbytecode proc parray] sourcefile
/opt/local/lib/tcl8.6/parray.tcl
Note that the procedure has to be already defined for this to work. And if Tcl's become confused about what file the code was in (because of dynamic programming trickery) then that key is absent.

In PyTorch, how to convert the cuda() related codes into CPU version?

I have some existing PyTorch codes with cuda() as below, while net is a MainModel.KitModel object:
net = torch.load(model_path)
net.cuda()
and
im = cv2.imread(image_path)
im = Variable(torch.from_numpy(im).unsqueeze(0).float().cuda())
I want to test the code in a machine without any GPU, so I want to convert the cuda-code into CPU version. I tried to look at some relevant posts regarding the CPU/GPU switch of PyTorch, but they are related to the usage of device and thus doesn't apply to my case.
As pointed out by kHarshit in his comment, you can simply replace .cuda() call with .cpu():
net.cpu()
# ...
im = torch.from_numpy(im).unsqueeze(0).float().cpu()
However, this requires changing the code in multiple places every time you want to move from GPU to CPU and vice versa.
To alleviate this difficulty, pytorch has a more "general" method .to().
You may have a device variable defining where you want pytorch to run, this device can also be the CPU (!).
for instance:
if torch.cuda.is_available():
device = torch.device("cuda")
else:
device = torch.device("cpu")
Once you determined once in your code where you want/can run, simply use .to() to send your model/variables there:
net.to(device)
# ...
im = torch.from_numpy(im).unsqueeze(0).float().to(device)
BTW,
You can use .to() to control the data type (.float()) as well:
im = torch.from_numpy(im).unsqueeze(0).to(device=device, dtype=torch.float)
PS,
Note that the Variable API has been deprecated and is no longer required.
net = torch.load(model_path, map_location=torch.device('cpu'))
Pytorch docs: https://pytorch.org/tutorials/beginner/saving_loading_models.html#save-on-cpu-load-on-gpu

How to call in C lua modules

To simplify things, let's assume, that there are two Lua scripts, one program and one module, e.g:
sample.lua
local sample = {}
sample.fun1 = function()
end;
return sample;
I'm using it in program, like this:
program.lua
local sample = require("sample");
sample.fun1();
And now i'm trying to use the same module in C (first running lua program, what is important here), something like this:
luaL_dofile(luaState, "program.lua");
...
lua_getglobal(luaState, "sample");
lua_getfield(luaState,-1, "fun1");
or
luaL_dofile(luaState, "program.lua");
...
lua_getglobal(luaState, "sample.fun1");
But both versions causing crash. My question here: Is it possible to use somehow module, which was previously used in program? For this example it is of course nonsense, but my system is far more complicated and i need this functionality. Maybe some other approach to achieve this?

Ctypes mozilla unknown error

In a mozille extension I run:
SecSess.Logger.info("ctypes test");
Components.utils.import("resource://gre/modules/ctypes.jsm");
SecSess.Logger.info("1");
this.lib = ctypes.open("libcrypto.so");
SecSess.Logger.info("2");
var a = new Uint8Array(1<<10);
SecSess.Logger.info("3");
var ptr = new ctypes.uint8_t.ptr(a.buffer);
SecSess.Logger.info("4");
Why this ugly logging after each step you might ask? Well this code fails without showing me an error. (or at least I can't find the error message)
This is printed:
ctypes test
1
2
3
So the 5th log message is never printed which means the following statement never completes:
var ptr = new ctypes.uint8_t.ptr(a.buffer);
This is a simplified version of some old code I have to work with and which I also found online as being valid. However it doesn't work. This add-on wasn't developped using the new SDK with jpm. Quite frankly I don't know how and when it was developped but I need to run some tests on it. It comes with a few source files ordered in a components and a modules directory and a chrome.manifest and install.rdf in the root. I copied these files to the extension directory of Mozilla in order for it to work. The extension executes but there seems to be a problem with ctypes. Aren't ctypes fully supported anymore or are these old style add-on no longer valid for the modern Firefox?
Regards,
Roel
I think they landed a a patch to disallow making a pointer from buffers. I'll double check.
Edit:
Ah per this: https://developer.mozilla.org/en-US/docs/Mozilla/js-ctypes/Using_js-ctypes/Working_with_ArrayBuffers, you don't have to wrap it with a ctypes.uint8_t.ptr just pass it like a.buffer to wherever you need it. :)

Lua check if a file is open or not

I'm trying to script a lua file to check if a certain file is open. Then I want it to close that file if it is open. I know how to check if the file exist but I need to know how to check if the file is open, meaning the file is running.
Lua, like C, C++, and pretty much every other language, can only close files that it opens itself. You cannot close files open by other people (not with standard Lua calls); this would be incredibly rude.
So you can't test to see if a file is opened by someone else. Nor can you close their file. There may be system API calls you could make to do this, but you would have to give Lua scripts access to those APIs yourself. Lua's standard libraries can't do this.
Sounds like you want to check which if any programs have a given file open.
first thing that comes to mind is parsing the output of lsof on linux.
fd = io.popen("lsof path/to/my/file")
fileopened = (#fd:read("a*") > 0)
Kind of a hacky way to do it, but it works:
processname = "process_name_here.exe"
filedata = io.popen("tasklist /NH /FO CSV /FI \"IMAGENAME eq "..processname.."\"")
output = filedata:read()
filedata:close()
if output ~= "INFO: No tasks are running which match the specified criteria." then
-- Program is running. Close the program
os.execute("taskkill -im "..processname)
else
-- Program is not running
end
Just make sure to replace "process_name_here.exe" with the process name that shows up in task manager
Alternatively you can just use this to close it without checking if it was actually running:
os.execute("taskkill -im process_name_here.exe")

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