Is It Really The Worst Interview Question?

Posted on So, 2014-07-27 in thoughts • Tagged with thoughts, programming, software-engineering

Recently I read a blog post about the supposedly worst programming interview question. So here is the question:

Write a function that can detect a cycle in a linked list.

Basically the guy that asked the question was testing of whether you've heard of Floyd's cycle-finding algorithm (aka. the tortoise …


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Some Notes on CBC-Mode, IVs and MACs

Posted on Mo, 2013-10-28 in crypto • Tagged with cryptography, security

I recently read this tweet which gave an example for why you should use good IVs in your crypto. The tweet was:

Why you should always use good IVs in your #crypto http://i.imgur.com/jxUv3ha.png

This is the about the example that was given [1]

$ echo 'Give …

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Current State of Android "Physical" Security

Posted on Mo, 2013-09-02 in android • Tagged with android, security

About a year ago I gave a talk to my fellow students about the security of android devices, once you get physical access to them. This post will be pretty much that talk plus some additional infos and links. You can find the slides here [1].

The Evil Maid Attacks …


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Hunting Memory Leaks in Python

Posted on Sa, 2013-08-31 in coding • Tagged with python, coding, debugging

The first thing you might say: "Memory leaks in python? What the hell are you talking about? Python has garbage collection. How is this possible? I don't have to care about memory management!" Well you don't. Until your python project blows up directly into your face because it eats up …


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Key Transition 2013

Posted on So, 2013-06-16 in misc • Tagged with openpgp, misc

Today I sent my old OpenPGP key to retirement. I have been really sloppy with this key. I never changed my encryption subkey and signed everything with the master key. With the new key I'll store the master key offline and will sign/encrypt with subkeys, which I'll rotate much …


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