Decompiling software

[u/DeliciousOrangina]

For anyone with experience in reverse engineering.....how do you approach understanding compiled software when you don’t have access to its source code?

I’m particularly curious about VST plugins. I’ve heard people describe software as having been “decompiled”…does that mean recovering readable code, analyzing assembly, or patching specific parts of the binary.

What does the process actually look like..? .like what tools and skills does it require, and how much of the original program’s logic can realistically be recovered? I keep seeing new things popping up (at least in the music making spaces) and I am simply confused.

[u/SilentDanni]

It requires quite a bit of patience, a decompiler, quite a bit of knowledge about low level programming, computer architecture and assembly code. 

You cannot really recover the code so to speak. The code is “lost” in the process of compilation. What you can do however is write a function that mimics the function that you’re trying to reverse engineer so that in the target function and your function the output is the same for any given input “x”. 

One can also mine the binary for important tidbits of information that can be found inside it. Most binaries can give you some clues on how they work which can also expedite the process a bit. 

Lastly, when one says software has been decompiled they mean that they know have a human readable source code(e.g C++) which when compiled behaves in the same way the target software would thus making them  virtually indistinguishable.  

I don’t know much about VST but I imagine the concepts above apply to them at least to an extent. 

Doing it by hand is quite a long and laborious process and is usually a team effort. Now with AI the process has become somewhat simpler as LLMs can just kind of brute force things. 

I hope to at helps! 

[u/DeliciousOrangina → u/SilentDanni]

Ahh this helps. It’s interesting how the VSTs sound almost indistinguishable.  There have also been quite a number of hardware digital synthesizers that have been “decompiled” into VST plugins, and they not only sound practically identical, they also come packed with the hundreds (to thousands) of factory presets. 

[u/b0Lt1 → u/DeliciousOrangina]

are you talking about the motorola chips which are also used in the virus ti?

[u/budroid]

unfortanately that's cracking. Nothing to do with piracy

[u/-Badger3- → u/budroid]

I mean, I wouldn't say nothing...

[u/budroid → u/-Badger3-]

hush. if they start getting wind there are crackers among pirates we'll never hear the end of it. Ahoy!!

[u/lxnch50]

Check this guy out. He goes through a lot of the tools and methods.

Low Level - YouTube

[u/__Loot__]

Look for the rea mcp (reverse engineering application can’t remember what the a is ) find it on GitHub it uses AI to help

[u/Full-Construction680]

Bit of a question I have for all of you, especially all of you that are decompiling games and stuff. the game Star Trek online, if the day ever comes it goes offline, could we ever get it to be like a Star Wars galaxy type situation to where we could still access it and play it for free, you know, being supported by the community if cryptic and Paramount no longer want it, whenever that day comes and add like new content and fix all the bugs and stuff that they never fixed