Christian Hascheks blog

I scanned the whole country of Austria and this is what I've found - IP cameras, printers, industrial controls to name a few..

Fri, 08 Feb 19 08:30:00 +0000

Disclaimer: This article is the result of a few weeks of research. I did report the most..

Sending Emails to my 3-year-old - How I'm using email and timecapsules as a fun legacy for my son to find

Sun, 05 May 24 14:32:00 +0000

In 2020 just in between two lockdowns, my wife gave birth to our son Linus. I'm not going to des..

The ultimate Raspberry Pi gitops cluster - Booting and auto provisioning a Docker Swarm cluster with PXE and enjoying zero-downtime deployments from a single git repository

Thu, 06 Nov 25 13:37:00 +0000

Ever since the first Raspberry Pi came out I wanted to create some kind of cluster with them. The fi..

The encrypted homelab - creating the most secure homelab there is

Wed, 17 Jun 20 23:06:00 +0000

If you are a homelabber or are in charge of a bunch of physical..

Let's analyze over twenty thousand proxies - It won't get much better

Tue, 07 Jul 15 12:37:00 +0000

In my last post I tested 443 proxies and analyzed how safe the..

So you have been scammed - a small guide on how to strike back and be a bad scamee

Fri, 31 Aug 18 20:15:00 +0000

So you have been scammed

It's okay, it happened to the best and even large companies aren't bul..

How to fight child pornography with a Raspberry Pi and deep learning - Finding illegal content with just 10 Watts of power

Sun, 17 Jun 18 19:22:00 +0000

The thing about the internet is, if you give people an open platform, the scum will follow.

Analy..

PHP script that filters moods from twitter - ..how depressed is the web?

Sat, 03 Jan 15 13:02:00 +0000

Some time ago I saw a TED Talk where a programmer made a twitter-feeling project.

He wrote a progra..

Temperature visualization - from 6 months of data

Sat, 03 Jan 15 12:57:00 +0000

In my last project I used a Raspberry Pi and a few temperature sensors to record the temperature fro..

Accepting Ethereum payments without external services - You don't need to pay for merchant systems

Fri, 09 Jun 17 07:17:00 +0000

When I first thought about implementing payment via a crypto currency I looked at the available solu..

DIY cloud lamp for fun and profit - ok, just for fun.. no profit involved

Fri, 19 Feb 16 10:21:00 +0000

NOTE: For maximum fun, activate the [Cloud to butt](https://chrome.google.com/webstore/detail/cloud-..

How to defend your website with ZIP bombs - the good old methods still work today

Wed, 05 Jul 17 17:22:00 +0000

[update] I'm on some list now that I have written an article about some kind of "bomb", ain't I?

--..

My door sends me chat messages - Raspberry Pi powered door sensor and Rocket.Chat bot with some neat info

Mon, 23 Jan 17 12:13:00 +0000

The result

Github repo: [Link](https://github.com/geek-..

How a scammer stole 500$ from me and in the end begged me not to tell his parents - Thank god not all scammers are professionals

Tue, 27 Sep 16 11:22:00 +0000

[Update] If you have been scammed then you might want to read my newer post [So you have been scamme..

Chromebooks for Work & Classrooms - are they worth it?

Mon, 07 Dec 15 10:51:00 +0000

When I first heard about Chromebooks a few years ago, I thought the Idea is awesome but I didn't rea..

Making an awesome dashboard for your crypto currencies in 3 steps - using InfluxDB, Grafana and PHP

Thu, 03 Aug 17 18:03:00 +0000

If you have invested in crypto currencies in order to hodl them you might find yourself checking the..

Forget Pay2Win - the time has come for Learn2Win - how to reward players in any game for academic achievements

Sun, 05 Jun 16 02:06:00 +0000

https://www.pictshare.net/200/8bdc5ae944.jpg" style="float:right;" /..

Raspberry Pi controlled LEDs - to visualize the up-state of my servers

Fri, 02 Jan 15 19:25:00 +0000

A friend of mine who is also a sysadmin recently said to me that if a device he managed went offline..

Raspberry Pi 2 wireless temperature box - The π² + wifi + 1wire sensor = pure awesomeness

Thu, 19 Mar 15 00:04:00 +0000

Two years ago I made a project where I used a Raspberry Pi to ..

Announcing: Socialcube LITE - My proof-of-concept evolved to a intuitive platform which is free for every educational institution

Sun, 04 Jan 15 17:06:00 +0000

The support I got for my XP-based grading system w..

Water cooled NAS made from spare parts - with Macguyverish solutions for common problems

Sun, 27 Sep 15 23:45:00 +0000

In this project I will build a water cooled NAS made from [my 51$ water cooling solution](https://bl..

hackthissite.org ascii code picture challenge -

Mon, 05 Jan 15 21:15:00 +0000

I recently tried the second programming mission on hackthissite.org and I found it very fun to code ..

Repairing a closed loop CPU water cooler with aquarium tubing - air bubbles... those f***ing air bubbles

Sun, 29 Mar 15 01:25:00 +0000

I had this broken KÜHLER H2O 620 closed l..

Is Guetzli useful in production? - It's much better than google promised - 51% smaller images

Fri, 24 Mar 17 13:51:00 +0000

[Google recently](https://research.googleblog.com/2017/03/announcing-guetzli-new-open-source-jpeg.ht..

That (not so) awesome time the police raided my home - lesson learned: Don't click on links random people send you

Wed, 18 Nov 15 13:22:00 +0000

A few years ago I saw the blooming of new IRC communities. In fact I haven't seen so many people in ..

Why hackits are the first thing I teach new classes - they represent everything I love about computer science

Wed, 01 Jun 16 12:25:00 +0000

[update] I've created a website called 0xf.at which hosts all my hackits.

Ev..

My company just turned 10 and it was quite a ride - also: about the time Thomas Schranz and I almost invented Dropbox

Sun, 10 Jan 16 16:48:00 +0000

Hello readers!

This entry will be about my company Haschek Solutions a..

HTML5 heat spreading simulation - with a simple JS algorithm

Wed, 24 Feb 16 12:22:00 +0000

I was reading an algorithm book the other day and found a rather interesting section about simulatio..

IKEA Server Rack - nope, not a lack rack

Fri, 08 Jan 16 17:03:00 +0000

I recently moved and had the most geeky problem there is:

**Where do I put my servers and the coffe..

DIY vertical hydroponic system - grow vegetables in small spaces

Sun, 23 Apr 17 11:14:00 +0000

I wanted to do this project for years but only recently decided to give it a try. Over the last few ..

My XP-based grading system - a modern approach to grading in the year 2014

Tue, 30 Dec 14 01:28:00 +0000

I have been working on an XP based grading system since long before I became a teacher. As a student..

Raspberry Pi controlled power sockets - it's as easy as it sounds

Sun, 27 Dec 15 01:28:00 +0000

Disclaimer: I'm not an electrician and I would not use this proof-of-concept in reallife because it ..

Teaching your fish tank LEDs new tricks - for just a few bucks and you can even make some virtual clouds

Sat, 09 Sep 17 17:48:00 +0000

**In this project I'll upgrade a cheap fish tank LED light to be dimmable, controllable via Wifi and..

My door sends me emails - Simple and cheap Raspberry Pi burglar alarm

Wed, 27 Apr 16 21:41:00 +0000

[UPDATE] I've rewritten this article for a more modern approach: [My door sends me chat messages](ht..

Raspberry Pi + Deep Learning home security system - From start to finish

Tue, 27 Mar 18 22:08:00 +0000

How to visualize RADIUS connections - by parsing Windows Server log files

Fri, 22 Jan 16 13:27:00 +0000

Note: This tutorial is working for Windows Server 2003 to 2012R2 with NPS installed. It's not curren..

Reverse engineering your mobile banking app - to make a PHP script that automates checking your balances

Thu, 05 Apr 18 10:55:00 +0000

Our Austrian banks (seemingly) hate developers as they don't give you an API to check banking statem..

Raspberry Pi controlled cactus lamp - adding power to a cheap lamp

Wed, 03 Jan 18 11:13:00 +0000

This christmas I got this LED cactus lamp that seems to be in every store now. Since it's so light a..

Analyzing 443 free proxies - Only 21% are not shady - what about the other 79%?

Tue, 07 Jul 15 12:37:00 +0000

[UPDATE] My web service Proxy Checker is now online! You can use it..

DIY: Cheap wall mounted, water cooled PC for 51$ - with LED backlight and and all the good stuff

Sun, 27 Sep 15 22:08:00 +0000

[UPDATE] Test results are in!

Water cooling solutions are usually very expensive and I ..

Why are free proxies free? - because it's an easy way to infect thousands of users and collect their data

Tue, 07 Jul 15 12:37:00 +0000

[UPDATE] Check out the new post where I s..

DIY hydroponic pot for ~36€ - Easy to build and awesome for your plants

Fri, 05 Feb 16 14:12:00 +0000

So this is my first non-IT post on my blog and I hope it will help somebody save a few bucks.

One o..

Finding bombs in the forest - treasure hunters make it easy to find them

Wed, 26 Oct 16 10:07:00 +0000

In the end of WW2, when Vienna was overtaken by allied forces, the Wehrmacht was pushed in the woods..

What would happen if you'd embed a remote JPEG with a HTTP link but the remote server is forcing HTTPS? -

Fri, 26 Jun 15 10:37:00 +0000

A few months ago I started going HTTPS for all my sites. One of the sites I was particularly excited..

Creating the safest ETH paper wallet with a Raspberry Pi - with a printer and without an internet connection

Thu, 22 Jun 17 14:53:00 +0000

Since I got asked the question about safe storage of ETH a lot I thought I'd make a tutorial for..

Making a simple Raspberry Pi Bitcoin/Ethereum trading bot - with rocket.chat and Slack status reporting

Mon, 17 Apr 17 10:15:00 +0000

[update] I have extended the bot to be able to trade **E..

Letting students mod school computers - with some amazing results

Sat, 23 Jan 16 12:59:00 +0000

I posted these photos initially on reddit/imgur and got overwhelmingly good feedback so I thought I'..

Raspberry Pi temperature monitor - with a nice graph and live updates

Sat, 04 Jul 15 22:15:00 +0000

After my Raspberry Pi powered door alarm I thought about implementing a temperature monitoring syste..

API Heaven ICO - finally an ICO for an existing product

Wed, 16 Aug 17 18:30:00 +0000

We have been busy the last year in polishing up an internal tool to a finished product.

Meet [API H..

Neue Reifeprüfung analyzed - The simple way to get a good grade

Tue, 09 Jun 15 10:29:00 +0000

This year was a special year for many teachers in Austria. We were "blessed" with the new Matura (a ..

App controlled garden irrigation system for less than 20 Bucks - put those Raspberry Pis you have laying around to a good use

Sun, 16 Jun 19 16:19:00 +0000

I was looking for a method to keep the plants happy without spending too much money on irrigation sy..

How I heat my home by mining crypto currencies - and cutting my electricity bill in half in the process

Tue, 23 Feb 21 13:37:00 +0000

After building my own smart meter using 4$ in parts I started chec..

Teaching in minecraft - logic gates have never looked so good

Thu, 10 Jan 19 21:33:00 +0000

edit Since I had so much success with my XP based grading system I thought I'd try to use actual gam..

Threat vector: Legacy static websites - Surely old HTTP-only sites can't be vulnerable if not updated for 5 years, right?

Sun, 24 Feb 19 10:07:00 +0000

A few weeks ago something happened that wouldn't change how a small company in Vienna thinks about s..

The perfect file server - Use all your disks for storage by booting a USB RAM disk

Sat, 31 Oct 20 13:37:00 +0000

If you've ever thought of building a file server, you probably had one or more of these thoughts

Stopping phishing campaigns with bash - how to poison phishing sites with fake data

Thu, 13 Aug 20 09:48:00 +0000

A few days ago my wife got a text message that was obviously a bad phishing attempt

![It says: Our ..

Build your own datacenter with PXE and Alpine - Who needs docker when you can run old laptops as blade servers

Tue, 15 Jun 21 08:28:00 +0000

I have recently developed a slight obsession over Alpine Linux. Everyone..

The curious case of the Raspberry Pi in the network closet - how we found, analyzed (with the help of Reddit) and in the end caught the culprit of a malicious device in our network

Wed, 16 Jan 19 10:50:00 +0000

Last week I got a message from my dad (who works with me at a client) with an image attached.

![Mes..

Making a smart meter out of a dumb one for 4 $ - and displaying it on an awesome dashboard

Fri, 19 Oct 18 10:50:00 +0000

As a geek who has a few servers and other devices at home I can't stop thinking about my power outpu..

Simple Raspberry Pi powered SMS Gateway - make your projects send SMS with a simple REST API

Mon, 06 Dec 21 07:21:00 +0000

Sometimes one needs to send a few SMS. Doesn't matter if it's because you have a [homelab](https://w..

SSH based comment system - because input fields are too easy

Fri, 28 Jul 23 10:00:00 +0000

This blog is now 11 years old and I've been thinking about a comment system for some time. I don't w..

The A1 Telekom Austria Hack - they came in through the web shells

Mon, 08 Jun 20 14:00:00 +0000

On the 3rd of February 2020 I received an encrypted email on 3 of my email addresses from a person c..

Let's Encrypt wildcard certificates - the easy way - Using DNS standalone - No credentials needed and working with every DNS provider

Sun, 01 Oct 23 14:00:00 +0000

Let's Encrypt is one of these services that seemed impossible just a few years ago. The first certif..

ZFS over iSCSI storage in Proxmox - all the power of ZFS without needing large disks in your nodes

Tue, 04 Jul 23 13:37:00 +0000

For almost a year now I have been using Proxmox as my main hypervisor in my homelab. When the electr..