Category: Hacking

Monitoring Android Emulator Network Traffic

It might be interesting for several reasons to monitor the network traffic of Android devices to watch the network  behavior of some apps. This article describes how to monitor network traffic running the Android AVD Emulator on Linux.

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GRUB Does Not Boot From SSD Disk

You have problems booting Linux from an SSD disk? You recycled an older notebook or you enhanced your newer notebook by replacing the old-school spinning harddrive with a new SSD drive and then… error: unknown filesystem. Entering rescue mode… grub rescue> You booted from an external drive and installed Linux to the SSD disk and …

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Hovercow

Passing Arrays as Parameter in C

Short answer: you can’t but yes, you can! This is an endlessly recurring question in many groups on the Internet. Today (2016/01/14) Google has 171 Million hits. This article answers the question and sheds some light on arrays in C. In the second part below I’ll discuss two-dimensional arrays as well. IMO, arrays are the …

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Fractals And Intel x86_64 Assembler

Some time ago I wrote this article about using integer operations to calculate fractal images. Currently, I’m giving a course which prepares for malware analysis. Among other things we deal a lot with Intel assembler and how compilers create and optimize code. The full code of everything discussed below (and also of the article referred …

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Evading Firewalls With OnionCat

Evading Firewalls With OnionCat

The Administrator’s TLS Certificate Hell

Nowadays, a responsible administrator should never run any service without TLS anymore. Unfortunately, this makes life even more difficult for several reasons. This article discusses some problems associated to certificates, specifically in respect to web applications which interactively connect to secondary services. On one hand TLS configuration requires a lot of knowledge to create a …

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Assembler on Arduino — Part 2

Some time ago I wrote this article about the build chain for assembler programming on Arduino. The article contained a simple blinking LED example. In the meanwhile I got several questions about Arduino and assembler. This article is about a more mature real-world blinking LED example. You can download the full source package here which …

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Learning C // Part III

After doing another course in C programming there is a new lesson. There are some hints on programming and most of them apply to any language, not just C. The following rules are recommendations which are true in most cases (but not all). You might also be interested in reading part I and part II …

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Calculating Fractals With Integer Operations

It was in the late ’80s when I started to become interested in fractals. At the time then computers very unbelievable slow compared to what we have today thus I tried to speed up the algorithms in several ways. This article is about using integer operations to calculate fractal images, more specifically I’ll explain how …

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