Develop Reference

Python3 Search the virtual memory of a running windows process

begin TLDR;
I want to write a python3 script to scan through the memory of a running windows process and find strings.
end TLDR;
This is for a CTF binary. It's a typical Windows x86 PE file. The goal is simply to get a flag from the processes memory as it runs. This is easy with ProcessHacker you can search through the strings in the memory of the running application and find the flag with a regex. Now because I'm a masochistic geek I strive to script out solutions for CTFs (for everything really). Specifically I want to use python3, C# is also an option but would really like to keep all of the solution scripts in python.
Thought this would be a very simple task. You know... pip install some library written by someone that's already solved the problem and use it. Couldn't find anything that would let me do what I need for this task. Here are the libraries I tried out already.
ctypes - This was the first one I used, specifically ReadProcessMemory. Kept getting 299 errors which was because the buffer I was passing in was larger than that section of memory so I made a recursive function that would catch that exception, divide the buffer length by 2 until it got something THEN would read one byte at a time until it hit a 299 error. May have been on the right track there but I wasn't able to get the flag. I WAS able to find the flag only if I knew the exact address of the flag (which I'd get from process hacker). I may make a separate question on SO to address that, this one is really just me asking the community if something already exists before diving into this.
pymem - A nice wrapper for ctypes but had the same issues as above.
winappdbg - python2.x only. I don't want to use python 2.x.
haystack - Looks like this depends on winappdbg which depends on python 2.x.
angr - This is a possibility, Only scratched the surface with it so far. Looks complicated and it's on the to learn list but don't want to dive into something right now that's not going to solve the issue.
volatility - Looks like this is meant for working with full RAM dumps not for hooking into currently running processes and reading the memory.
My plan at the moment is to dive a bit more into angr to see if that will work, go back to pymem/ctypes and try more things. If all else fails ProcessHacker IS opensource. I'm not fluent in C so it'll take time to figure out how they're doing it. Really hoping there's some python3 library I'm missing or maybe I'm going about this the wrong way.

Ended up writing the script using the frida library. Also have to give soutz to rootbsd because his or her code in the fridump3 project helped greatly.

Placing a component using KiCad's Python API

I have a problem with KiCad's python API (5.1), I cannot find a way to add a component onto the PCB.
I found some examples but they no longer work with the version of KiCad I am using. The next step is going through the C++ code to understand how a component is placed on the board, but before that, I thought was worth asking for help here.

Adding a component is quite easy, just instantiate a module and place it on the board.
m = pcbnew.FootprintLoad("D:/path/to/lib.pretty","footprint_name")
board.Add(m)
But be aware that you cannot add the same module multiple times, you have to create multiple modules. I found this out with hours of debugging.
footprint = pcbnew.FootprintLoad("/usr/share/kicad/modules/MountingHole.pretty", "MountingHole_3.2mm_M3")
board.Add(pcbnew.MODULE(footprint))
board.Add(pcbnew.MODULE(footprint))
board.Save("board.kicad_pcb")

Keyboard Control Python

I want python to click Enter. However, I don't want to install any outside extensions. I want it to click enter without using them. I found many resources like win32 but I want to do it without using external resources. I don't mind which version of python it is on.
Is this possible?
If so, how?
I have looked on the web but couldn't find anything. Please, can someone help?
Thank you in advance.

Yes.
It should definitely be possible using the ctypes library to talk directly to the Windows dlls
If you don't want to install a helper module that has done all this for you, then you pretty much have to do it old school by going after the really low level code.
In short, call the SendInput function of user32.dll by using ctypes.windll.user32.SendInput. Good luck with getting the parameters correct - I don't have the patience to figure it out for you.
Here are the docs for the user32.dll SendInput API
Here is a helpful resource for figuring out the data types. This is actually part of ctypes and can be imported by import ctypes.wintypes but I find it instructional to read the actual code.
So for example, to create a WORD with the value of the Virtual Key Code VK_RETURN, I think it would be
>>> ctypes.wintypes.WORD(0x0D)
c_ushort(13)
But there is a lot more you have to piece together from there. Just build up your parameters and call the function.
Last hint, use the examples in the second link for how to build "C" type structures. Then build one yourself using ctypes.Structure

How steamkit work?

Currently, i want to implement a trading system for steam games (with python).
So, i searched github, but sadly, there are only
https://github.com/Jessecar96/SteamBot
https://github.com/Jessecar96/SteamKit2
Yeah, they works good. But they are C# -- don't tell me python can't do this :).
So, i want to start with the steamkit part. I thought it's not difficult(maybe just some web-apis), but when i kinda review the code of SteamKit2, i find it seems use TcpConnection to Steam Network, don't know how they get the protocol.
Does anyone has any idea about this, i think about use python load steamkit2.dll, but im really noob with C#

You don't want to use the SteamKit2 port on that repository. It is a branch (and an out dated one at that) of the official SteamKit2 repository. It also looks like they are attempting to get rid of the branch based on this issue discussion.
To answer your question, there is a port of SteamKit to Python. It is called PySteamKit and is written by one of the contributors to SteamKit2.
Unfortunately, there doesn't seem to be much documentation in the Wiki of either the official SteamKit or the Python port on how to use the package. You may have to look at the Samples provided by SteamKit which are in C#.

How to encrypt files in twisted?

I'm using twisted to create a server.
Problem is, I must protect my code. Since I don't want to publish it, I'm not really interess into obfuscation or compilation of the python code.
My problem is, my twisted application must run with root uid and a lot of people have root access to this server.
I don't care if they can read it, but I want sure they can't modify it!
What is the best solution, knowing I'm using twisted? I've seen in twistd, tapconvert and mktap that twisted can "encrypt" my code, but I didn't find any good documentation about that.
Anybody to help me?
Thanks in advance for any answer =)
Have a nice day!
/!\ EDIT:
I got another question, I've wrote my code following this part of twisted documentation: http://twistedmatrix.com/documents/current/core/howto/application.html so I launch my server using a command like twistd -y server.py --logfile ...
Since I'm doing that, I assume I can't use software like cx_Freeze to hide my code right ?

You have a number of problems here.
my twisted application must run with root uid
This is bad. If there are vulnerabilities in your application, then they will be made more serious by running as root. You should consider finding a way to not run as root. For example, if you only run as root so you can bind to a low numbered port, consider using authbind instead.
a lot of people have root access to this server
Perhaps you should limit privileged access to those people who actually need it. If that isn't an option, then perhaps you should at least limit access to people you can trust. Someone who has root on a machine can do anything they want on that machine, and defeat any scheme you dream up.
I don't care if they can read it, but I want sure they can't modify it!
You should ask them not to modify it, then.
I've seen in twistd, tapconvert and mktap that twisted can "encrypt" my code, but I didn't find any good documentation about that. Anybody to help me?
You shouldn't bother trying to use the encryption features of twistd and mktap. These don't prevent anyone from changing your code. At best they might prevent someone from reading some of it. As you said, this isn't even your goal. Even if it were your goal, someone with root access will be able to decrypt these files easily, so it doesn't even help there.
If you give code to someone, expect them to be able to do anything and everything they want with it. If you put code on a server, you are effectively giving it to everyone with root access to that server.
So, stop thinking about encryption and other technical issues and think of some other way to achieve your goals - fire the untrustworthy administrators, use an appropriate license on the code, get an actual contract, etc.

AFAIK, there is no way to prevent a root user from modifying a plain text file. Root is just that, they can do anything they want with it including modifying. Why do so many people have root access to the machine anyway?
If you're concerned, you really have two options:
Encrypt the files in whatever way you want (I don't know if Twisted does it or how)
'Compile' the code for your platform. There are a few Python compilers out there but I don't know if they work with Linux. I'm a free software guy so I want people to read and modify my code. Protecting it doesn't concern me.
I guess you do have a third option of protecting it legally with a license. But if they violate your license then there's the cost of taking them to court over it.
Not many options. Sorry.
Anthony