I forked this framework from pedro823 on Github. Credit to the source code of the framework itself should go to him. I however wrote the Main.py file in the src directory which was used for a challenge for my Cybersecuirty club.

A tiny framework to run python challenges in raw TCP.

Just clone this repo and you're already down for business! Wanna test it out? Just run ./ctfnc prod.

Code your own challenge in src/main.py. There, you'll need to define a main function that has two parameters: stdin and stdout.

• You should use the stdin.readline().strip() to get your input.
• You should use stdout.write() to output something. Remember to send \ns to the function!
• In case you want to output without sending a \n, use stdout.flush().
• Do NOT use input or print for reasons other than debugging.

After that, you can test it using ./ctfnc dev. You should be able to use it through your terminal.

With that working, try using ./ctfnc prod. it will start listening on a TCP socket (by default, 9001), and be able to serve your challenge up to 10 users at the same time (also configurable -- see below).

All configuration lies in config/config.py, although every single one of them is overwritable by env vars with the same name. for example, the config CTFNC_PORT is overwritable by the env var CTFNC_PORT.