LaForge's home page (Posts about dect)https://laforge.gnumonks.org/blog/tags/dect.atom2022-06-21T07:49:55ZHarald WelteNikola36C3 Talks on SIM card technology / Mitel DECThttps://laforge.gnumonks.org/blog/20200105-36c3-talks/2020-01-05T00:00:00+01:002020-01-05T00:00:00+01:00Harald Welte<p>At <a class="reference external" href="https://events.ccc.de/congress/2019">36C3</a> in December 2019 I had
the pleasure of presenting: One full talk about <a class="reference external" href="https://media.ccc.de/v/36c3-10737-sim_card_technology_from_a-z">SIM card technology from A to Z</a>
and another talk where I presented together with eventphone team members
about <a class="reference external" href="https://media.ccc.de/v/36c3-10576-mifail_oder_mit_gigaset_ware_das_nicht_passiert">Security issues in the Mitel SIP-DECT system</a>.</p>
<p>The SIM card talk was surprisingly successful, both in terms of a full
audience on-site, as well as in terms of the number of viewers of the
recordings on media.ccc.de. SIM cards are a rather niche topic in the
wider IT industry, and my talk was not covering any vulnerabilities or
the like. Also, there was nothing novel in the talk: SIM cards have
been around for decades, and not much has changed (except maybe eSIM and
TLS) in recent years.</p>
<p>In any case, I'm of course happy that it was well received. So far I've
received lots of positive feedback.</p>
<p>As I'm working [more than] full time in cellular technology for almost
15 years now, it's sometimes hard to imagine what kind of topics people
might be interested in. If you have some kind of suggestion on what
kind of subject within my area of expertise you'd like me to talk about,
please don't hesitate to reach out.</p>
<p>The Mitel DECT talk also went quite well. I covered about 10 minutes of
technical details regarding the reverse engineering of the firmware and
the communication protocols of the device. Thanks again to <a class="reference external" href="http://mirider.com/">Dieter
Spaar</a> for helping with that. He is and remains
the best reverse engineer I have met, and it's always a privilege to
collaborate on any project. It was of course also nice to see what
kind of useful (and/or fun) things the eventphone team have built on
top of the knowledge that was gained by protocol-level reverse
engineering.</p>
<p>If you want to know more low-level technical detail than the 36C3 talk,
I recommend my <a class="reference external" href="https://media.ccc.de/v/osmodevcon2019-100-aastra-mitel-dect-base-station-dissection">earlier talk at the OsmoDevCon 2019 about Aastra/Mitel
DET base station dissection</a>.</p>
<p>If only I had more time, I would love to work on improving the lack of
Free / Open Source Software realted to the DECT protocol family.
There's the abandoned <a class="reference external" href="http://dedected.org/">deDECTed.org</a>, and the
equally abandoned <a class="reference external" href="http://dect.osmocom.org/">dect.osmocom.org</a>
project. The former only deals with the loewst levels of DECT
(PHY/MAC). The latter is to a large extent implemented as part of an
ancient version of the Linux kernel (I would say this should all run in
userspace, like we run all of GSM/UMTS/LTE in userspace today).</p>
<p>If anyone wants to help out, I still think working on the DECT DLC and
NWK dissectors for wireshark is the best way to start. It will create a
tool that's important for anyone working with the DECT protocols, and it
will be more or less a requirement for development and debugging should
anyone ever go further in terms of implementing those protocols on
either the PP or FP side. You can find my humble beginnings of the
related dissectors in the <a class="reference external" href="https://git.osmocom.org/wireshark/log/?h=laforge/dect">laforge/dect branch of osmocom.org/wireshark.git</a>.</p>Patrick McHardy explains his Linux DECT stack at Linux Kongress 2010https://laforge.gnumonks.org/blog/20100923-linux_dect_stack_mchardy_lk2010/2010-09-23T03:00:00+02:002010-09-23T03:00:00+02:00Harald Welte<p>
At <a href="http://www.linux-kongress.org/2010/">linux kongress 2010</a>,
Patrick McHardy has just started to give his presentation on the Linux DECT
stack he has been working on in the last 1.5 years.
</p>
<p>
He looked at the <a href="http://dedected.org/">deDECTed.org</a> code
and found it very limiting, mainly targeted to passively listen into DECT
conversations, showing the weaknesses of DSC, DSAA and its implementations.
His new DECT stack is meant as a full and generic implementation for receive
and transmit.
</p>
<p>
I'm especially happy to announce that this project will now be hosted under
the Osmocom umbrella project at <a href="http://dect.osmocom.org/">dect.osmocom.org</a>. Right now it only has a README file and the git repository. However, a trac site will be up and running soon.
</p>Becoming the deDECTed.org spokesmanhttps://laforge.gnumonks.org/blog/20090210-dedected_spokesman/2009-02-10T03:00:00+01:002009-02-10T03:00:00+01:00Harald Welte<p>
Yesterday the members of the <a href="http://dedected.org/">deDECTed.org</a>
team decided to <a href="https://dedected.org/trac/blog/laforge_spokesman">pronounce me their official spokesman</a>.
</p>
<p>
It's not that I didn't already have way too much work anyway - but I strongly
agree that the project needs somebody who is non-partisan and not affiliated
with some of the bigger entities involved with the project.
</p>
<p>
Hopefully I can use this role to clarify some of the misunderstandings and
apparent misrepresentations that the project had to suffer with.
</p>