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Compiling rizin and r2ghidra

contact@cocacoding.com (cocacoding) — Thu, 01 Jan 2026 00:00:00 +0000

If you are looking to set up a powerful reverse engineering environment on Linux, combining Rizin with the rz-ghidra decompiler plugin is a great choice. While package managers often carry these tools, building from source ensures you have the latest features and fixes.

We will set up a clean installation using a local prefix (in ~/opt) to keep your system directories clean.

Why Build from Source?

At the time of writing, the dev branch is often preferred over stable for Rizin and its plugins due to rapid development and occasional compilation issues with stable releases. This guide follows the dev branch for both projects to ensure compatibility.

Installing Gentoo on EFI with LUKS

contact@cocacoding.com (cocacoding) — Mon, 08 Feb 2021 12:00:00 +0100

Installing Gentoo always introduces some pitfalls. This time we focus on EFI.

Prerequisites

Get the installation image on a USB drive or a disc:

dd if=Downloads/install-amd64-minimal-20201206T214503Z.iso of=/dev/sdh bs=4M status=progress

Then activate the network connection on the live installation OS, e.g.:

dhcpcd eth0
ifconfig

Then activate SSH to keep it simple. You can print the keys on the screen to check the connection from your master operating system:

/etc/init.d/sshd restart
ssh-keygen -lf /etc/ssh/ssh_host_ecdsa_key.pub

Now connect from your master operating system to the installation environment:

Writing Shellcode using the Text Section only

contact@cocacoding.com (cocacoding) — Mon, 21 Sep 2020 12:00:00 +0200

Shellcode is a sequence of instructions and is usually implemented in assembly language for a given architecture. Shellcode can be used to design and formulate a payload for exploitation.

Writing shellcode looks like an antiquated technique since they were used primarily to execute instructions when exploiting buffer overflows. Defense technologies like Data Execution Prevention (DEP) prevent the execution of binary code in writable memory regions. As a result, Code-Reuse attacks are the state-of-the-art strategy to construct and deliver payloads.

Exclude files from Eclipse indexing mechanism

contact@cocacoding.com (cocacoding) — Tue, 25 Aug 2020 13:15:18 +0100

If you develop software using Eclipse you might noticed that the indexing algorithm is powerful but might be reducing your setup performance. Eclipse is slowed down when you index too many files, for example from 3rdparty folders or other dependencies you don’t want to have indexed.

Building new filters in Eclipse

You can easily exclude the files by following these steps:

Mark your project by clicking on the name in the package explorer, use a right click to get into the context menu, select Properties.
Go to C/C++ General -> Paths and Symbols and select the topic Source Location in the window. Unfold your project folder and click on Edit Filter… on the right hand side.
Then click on Add… to add a filter, for example 3rdparty/ to remove all plugins from a project.

Now your project should be faster and you should see a gray line crossing out the folder you filtered in your package explorer.

Setting up a Gentoo VM for Linux Kernel Development

contact@cocacoding.com (cocacoding) — Mon, 17 Aug 2020 18:05:38 +0100

For decent Kernel development I needed a virtual machine and a Kernel I can control easily. Since I use gentoo for almost every system it was a clear choice I want to use gentoo again, even though it might be a bit time consuming to set it up.

For the start I will run gentoo inside VirtualBox to set it up, but I choose settings that allow me to run it in QEMU later.

Using FFmpeg to record video and audio

contact@cocacoding.com (cocacoding) — Mon, 17 Aug 2020 13:42:59 +0100

Have you ever tried to record some video or audio and video material using VirtualBox? Then you probably find out that the solution is too slow for your needs. With FFmpeg you are able to record not only video but also audio.

Installation

Install FFmpeg for your operating system, e.g. sudo apt install ffmpeg or if you are running gentoo Linux, do:

emerge -av pavucontrol ffmpeg

Then launch pavucontrol, start ffmpeg in your shell (just with some random parameters, only to see the third entry in the image below) and change the recording device in pavucontrol to monitor the audio from your device (third entry, Monitor of):

GDPR

contact@cocacoding.com (cocacoding) — Mon, 17 Aug 2020 13:03:17 +0100

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Contact

contact@cocacoding.com (cocacoding) — Mon, 17 Aug 2020 00:03:45 +0100

The best way to contact me is via mail, but feel free to reach out to me on LinkedIn or Twitter.

About

contact@cocacoding.com (cocacoding) — Mon, 01 Jan 0001 00:00:00 +0000

I mostly write about information security related topics and system programming. The site is built with Hugo and the Toigian theme.