31c3ctf devilish writeup

This is my first ctf writeup so I hope it won't be to horrible. And sorry in advance for my bad English.
I'll talk about devilish a web challenge from the 31c3ctf 2014 CTF. I'll give credit to one of our team members on this one "Michael", because we were both working on this challenge.

Well lets get to business with the devilish 30 points challenge. 24 teams solved it.
Here is the description of the challenge:

It's some devilish community public portal, we're pretty sure there's something else out there, a private portal maby, we'd like to know the secret behind it

How to compile and test your shellcode

I want to develop my hacking skills by learning how to do reverse engineering, so I’m learning assembly language. Without the assembly language, you’ll not be able to understand whats going on in the program.
But that’s not all. Assembly allows you also to make your own shellcode more cleanly and precise. But in this exercise you need to test your shellcode and see if it works as you expected. This will be a repeated task over and over agen so automating it will make you much faster and less prone to mistakes.