Creatives Unite!

There are wonderfull projects, that nobody can use… (Just have a look at GPG vor example.) What we have learned from smartphones and tablets is not that our parents can’t use tech. It is just not designed for them. If we just could give encryption, collaboration tools, open-data, … a face-lift, I believe good software will spread.

How will this work? Maybe if we all work a little bit together… Head over to Creatives Unite! Thanks at @SuddenGrey for the initiative.

IT-Studywork 2013

My bachelors’ thesis is up for voting at till 11th may. If you got 1 minute of time, head over there and vote for me.

The title of the thesis is Enhanced Android Security to prevent Privilege Escalation. The full version and the presentation slides can be downloaded in the publications area. There is also a Droicon talk, which is mainly based upon my findings of this thesis. Check it out, if you are interested.

Simple Mail Server

As an admin I have to be lazy. Currently I am moving several websites to a new server. This is workload enough, so I do not want to bother with stuff like a mailserver config. Especially, as I do not really see need for it. There are enough companies offering mail services, so I only want my server to accept mails for the domains he serves and then delivering them to my (or somebody else’s) personal mail address. And of course mails generated from the websites have to be sent out.

I chose exim4 for that purpose. After setting it up (as an “internet site” with splitting into several config files) via

dpkg-reconfigure exim4-config

I created the file /etc/exim4/conf.d/router/050_exim4-config_forwarding with the following content

### router/50_exim4-config_forwarding

# This router handles forwarding of mails to
# their appropriate recipients

  driver = redirect
  domains = +local_domains
  data = ${lookup{$local_part}lsearch{/etc/exim4/virtual/$domain}}

When a new mail arrives, this file is checked first and looks for forwarding rules in /etc/exim4/virtual/DOMAIN. So to set up forwarding for mail addresses create /etc/exim4/virtual/ with one forwarding rule in each line


[UPDATE 15.02.2014]
Although only accepting mail for several domains, I got some spam problems. Spam that was sent to me was then blocked by gmail after forwarding it. As the return address was not existing, my server sent a bounce message to gmail, which was blocked again. I ended up having a lot of frozen messages. To enable some blacklisting with exim on Debian is straight forward, if you know where to look. Check out this tutorial for further information:

Writing a Thesis is Fun

Stuff, that I stumbled upon, while writing my Bachelor’s thesis. Some might be funnier than others.


The Jailbreaker cannot always live in Maryland and give sweet candy to everyone!

[Source] – Don’t bother. I don’t live in Maryland either.


/* All this GUI stuff I assembled together via various
* howto’s and small code snippets found on the web. So dont
* wonder about this strange looking buttons etc.

[Source] – Did not see the app running. But by reading the code, this is just how a standard button in Android looks like.


You are in a hurry, and you don’t want to read this man page.

[Source] – Abosulutely right. But I still need the information…


What you need: […] A decent Internet connection & reliable electricity 🙂

[Source] – Thinking of my times in Uganda, I can completely understand it…


If you really absolutely need more capacity,
you can ask a wizard to enlarge me.

[LaTeX logs] – Seriously. I really abolutely need to get my thesis compiled!