Touch events
I wrote some code to experiment with touch events. When you touch the surface below on a device that generates
touch events, you should see some dots being drawn and information being
displayed in the text area below. I have used this to implement panning and
zooming in diagrams on the WHY2025: Reviewing
live-bootstrap page.
WHY2025 programme
Next weekend, I will go to the WHY2025
hacker camp, which takes place from August 8 to and including August 12. Today,
I studied the programme including
the self organized events to see which talks and workshops I want to attend.
Below it gives my selection. Note that some of the lectures and workshops are
overlapping, so it is definitely not the final programme. The times and places
that are bold or italic are events that are not recorded. The other talks are
recorded and will be made available to watch later.
Thursday, August 7, 2025
Friday, August 8, 2025
Saturday, August 9, 2025
- 10:00–10:50, Delphinus: Nerdkunst: Gentle and interactive introduction to generative art
- 10:00–12:00, Electronics: BlinkyTile Soldering Workshop
- 11:00–11:50, Andromeda : The EU Just Made Product Security Mandatory — Now What?
- 11:00–11:50, Delphinus: Integrity violation: toxic workplaces in infosec
- 12:00–12:25, Cassiopeia: qryptr - airgapped secure hardware messenger
- 14:00–14:25, Cassiopeia: Building a Robot Visor: How and Why
- 14:00-16:00, Green Ninjas: Reversing Engineering (Pwn Workshop 1)
- 14:35–15:00, Cassiopeia: Elephants, ants and introduction to topology
- 15:00–15:25, Andromeda: DNA & Molecular Biology: A 2025 digital view
- 15:00–16:30, Workshop Giotto: Badge Fun for Young Coders!
- 16:00–16:50, Cassiopeia: Summoning Shenron: Building the Cyber Saiyan Badge
- 16:00–16:50, Delphinus: The "O" in OT...or is it the "Ohhhh..." in OT?
- 17:00–17:50, Brachium : Bootstrapping a Museum with Open Source
- 20:00–20:50, Delphinus: All about BadgeHub
- 20:00–22:00, Workshop Euclid : Bring Your Badge to Life and personalize it to your taste.
- 20:00–20:50, Brachium: May Contain Hardware Acceleration: Building a 3D Graphics Accelerator in FPGA for the MCH2022 Badge
- 20:00–22:30, Electronics: Digital Music Synthesis/Solder workshop with ArduTouch music synthesizer kit
- 21:00–22:40, Delphinus: Documentary screening: Hacking Hate (2024)
- 22:30–23:10, Party Area: Symphony of Fire (Demo): Music created from explosions, fire and lightning!
- 23:30–02:00, Party Area: Movie: Sneakers
Sunday, August 10, 2025
- 10:00–10:25, Brachium: Reinventing woodwind instuments
- 11:00–11:25, Brachium: Ctrl+Alt+Delete Anxiety; a guide to mental wellness
- 11:00–11:50, Cassiopeia: Dutch fun! (damentals)
- 11:00–13:00, Electronics: Sensing the World Around you with EMF!
- 12:00–14:00, Serendiep: RF workshop
- 14:00–15:30, Brachium: Het Grote Cyber Debat
- 14:00-16:00, Green Ninjas: Binary Exploitation (Pwn Workshop 2)
- 15:00–15:25, Cassiopeia: Bare metal programming from the ground up
- 16:00–16:50, Andromeda: Dries Depoorter
- 17:00–17:50, Cassiopeia: How to make a Domain-Specific Language for non-devs (so they don't need AI)
- 19:00-19:50, Andromeda: Reverse Engineering Life: A teardown of the DNA source code of a whole bacterium
- 19:00–21:00, Workshop Euclid: NPO Radio 1- Dijkstra & Evenblij Ter Plekke
- 20:00–20:50, Delphinus: Packets Over Any Wire: Alternative Networking Mediums for Hackers
- 21:00–21:50, Brachium: CyberSecurity Rant - a safe space to talk about what annoys you in cybersecurity
- 21:00–21:50, Delphinus: GNU Taler: beyond digital money
- 22:30–23:10, Party Area: Symphony of Fire (Show): Music created from explosions, fire and lightning!
- 23:30–02:00, Party Area: Movie: Wargames
Monday, August 11, 2025
- 10:00–10:50, Cassiopeia: Autarkie - Instant grammar fuzzing using Rust macros
- 11:00–11:50, Brachium: Passive and active RADAR using Software Defined Radio
- 11:00–11:50, Delphinus
12:00–12:50, Cassiopeia: Weakpass
- 11:30–13:30, Electronics: Sensing the World Around you with EMF!
- 15:00-15:50. Cassiopeia: Reverse Engineering Life: Afterparty.
- 16:00–18:00, Electronics: Build Your Own Satellite Ground Station
- 15:00–15:50, Andromeda: The WHY, the How, the What. An assessment of TETRA End-to-end
- 17:00–17:50, Cassiopeia: Reviewing live-bootstrap
- 20:00–20:50, Brachium: Nerding out over silly machines
- 21:00–23:00, Electronics: Synth Meetup
Tuesday, August 12, 2025
Multiple days
WHY2025 Day 0
In the evening, I arrived at WHY2025 hacker
camp. At 20:06, I got the wristband for the camp.
I also received a welcome backage (not including an electronic badge) that
included a map of the camp. I spend some time
to set up my tent and brought a visit to the Angel tent to tell that I have
arrived. I am staying with the NLHS village. I talked with some people staying
with the village.
WHY2025 Day 1
I woke up around eight. From ten till twelve, I helped as a parking angel,
showing people arriving by car where they can park and take care that they
park correctly on the field. After that I stayed some time at the NLHS village
talking with some other villagers. In the middle of the afternoon, I walked to
the Noordhollandsch Kanaal ("Great North Holland Canal") to visit the
Serendiep ship.and walked
through the 'labyrinth'. I spend some time back and discovered that there
was a power outage, which started at 14:58. Just before five in the afternoon,
I walked to the main stage, called Andromea, only to find out that the opening
is delayed for one hour. A sat close to a music stage where there was a jam
session going on. Then at six o'clock it was announced that all presentations
and workshops were cancelled for today. I went to Angel tent, called Haven, to
wait for the dinner. During dinner I met with some people and we talked a bit.
In the evening, I talked with some more people in and around the tent of the
NLHS village.
WHY2025 Day 2
I got up around nine. Did not sleep that well for the second part of the
night. During the day, I did the following things:
- At 10:00, I attended the presentation Nerdkunst: Gentle and interactive introduction to generative art by
Nick Boucart who
runs the website NerdKunst.
Recording.
- At 11:00, I attended the presentation The EU Just Made Product Security Mandatory — Now What? by
Piet De Vaere. It gave some interesting
information about the security regulations including the Cyber Resilience Act. Recording.
- As 12:01, I attended the presentation qryptr - airgapped secure hardware messenger by Thomas about the
qryptr device, an air gabed encryption
device. Recording.
- When I walked back to the NLHS village, I saw Quantum Jungle by Robin
Baumgarten.
- I spend some time there and talked with some of the visitors to the tent,
who either came for buying and MCH badge, see the fire exstinquiser badge
or for some other reason. Some also show interest for the fractal puzzles
that I brought with me. One woman gave me two small dices and I start
carrying them.
- At 14:01, I went to the Green Ninjas village to attend the
Reversing
Engineering (Pwn Workshop 1) workshop, but after heard the initial
introduction, I decided not to stay.
- At 14:35, I listened to the presentation Elephants, ants and introduction to topology by Aleksandra Fedorova. A short but interesting talk about manifolds, an
important concept from topology, which is an area of mathematics.
Recording.
- At 15:00, I listened to the introduction of KiCad for Beginners workshop, but left after that.
- I visited the D24D area, where there will be Build Your Own Meshtastic Pager (One That Doesn't Explode) workshop.
But it was already fully booked for all days.
- At 16:01, I listened to the presentation Summoning Shenron: Building the Cyber Saiyan Badge. Recording.
- Played a bit with the Algorithm
Machine that was standing somewhere along a path.
- At 20:00, I attended the presentation May Contain Hardware Acceleration: Building a 3D Graphics Accelerator in
FPGA for the MCH2022 Badge by Ruud Schellekens. Interesting talk. His implementation used about 94%
of the FPGA. He showed two demos. Recording.
- At 20:54, I got my copy of the 40th anniversary edition of Phreak at the
Phrack 40th
Anniversary Release Party.
- At 21:00, I attended the presentation How to rig elections by Vadim Makarov. He is the co-author of the paper Dual approach to proving electoral fraud via statistics and forensics.
Recording.
In the evening, they started handing out the badges. I heard that there was a
very long queue and also some rumour that the last people in queue might not
even get a badge. Less badges were ordered than there were tickets sold and I
heard that the defect rate is rather high. So, maybe not all people will get
a badge. I will see tomorrow if there are any badges left.
WHY2025 Day 3
I got up around nine. I did sleep better than yesterday night, although there
people talking outside deep into the night. During the day, I did the following
things:
- At 10:04, I listened to the presentation Reinventing woodwind instuments by Molenaar. Quite interesting talk.
Recording.
- At 10:44, I arrive at the Hardware Hacking Area and build the EMF Explorer badge of the Sensing the World Around you with EMF! workshop by Darcy Neal. It only required some soldering. A worthy addition to my
collection of gadgets.
- At 12:00, I joined the RF workshop by PE1BMC. The first part was an interessing presentation of RF and it
ended with some RF experiments using an 120Gh transmiiter and receiver.
- At 15:01, I listened to the presentation Bare metal programming from the ground up by
Ayke Maaike van
Laethem. Sheets for
the presentation. Really interesting. Sad that not more time was allocated
for the presentation to have room to go in some much more detail.
Recording.
- At 16:01, I listened to the presentation The Flipper Blackhat by Ryan Walker which is about the Flipper Blackhat. It was a bit about all the tecnical details, such
as the schematics and the embedded Linux that was used. It sounded a bit
like as a sales pitch. Recording.
- At 17:00, I listened to the presentation How to make a Domain-Specific Language for non-devs (so they don't need
AI) by Meinte Boersma. Recording. He mentioned the RegelSpraak domain-specific language (DSL) that is used by the Dutch tax office to
specify the rules for calculating, for exmple, the income tax laws. He also
mentioned the projection editor frameworks and lionweb.io. I do not agree with
his statement that parsing is hard, especially if I think about something
like IParse Studio. When I later met him, he explained that textual DSL are
considered too nerdy by most non-technical end-users, which makes sense.
- At 20:00, I listened to the presentation Reverse Engineering Life: A teardown of the DNA source code of a whole
bacterium by Bert Hubert. Very
interesting and engaging talk (which was not a real surprise having seen
his pervious talks). Recording.
- At 23:00, I listened to the presentation EntrySign: create your own x86 microcode for fun and profit. They
explained how they did it and then demonstrated that they could modify the
microcode of an AMD processor to always return 4 when the random
instruction is called. Recording.
WHY2025 Day 4
These are some of the things I did during day 4 of WHY2025:
- Around midnight, I attended the Stargazing event at Øl Telecom village. The person who was
organizing it was still doing a shuttle-bus shift. When we arrived he
let us look at Vega, the
Double Double,
and the Ring Nebula.
- Around 1:30, I watched an PDP-11 starting up at the Home Computer Museum tent and I entered some commands.
- I went to sleep around two and woke up around seven. I tried to sleep a
bit more and got up around ten.
- At 11:04, I listened to the presentation Passive and active RADAR using Software Defined Radio by
Jean-Michel Friedt. It was a bit of information overload with
slides with a
lot of text. Recording.
- At 15:00, I listened to the presentation The Menopause Gap: How Silence and Stigma Are Putting Women at Risk by
ChewyMoose. Recording.
- At 16:31, I arrived at Cassiopeia, where at 17:00, I gave my presentation
Reviewing live-bootstrap. One person from the public made an
interesting suggestion, to have a look at the standard library of the
GNU Mes project. Recording.
- Around 21:45, I looked around the Hardware Hacking Area where there was a
Synth Meetup.
- At 22:17, I bought a BlinkyTile. I will put together later.
- At 23:01, I listened to the presentation A journey into reverse engineering arcade PCBs for video game preservation
via FPGA emulation by Solal Jacob. Recording.
WHY2025 Day 5
This is the last day of WHY2025. The official
program will end at 17:00 after the closing session. These are the things I
did:
- I got up around nine in the morning and after having had something from
breakfast, I brought some of my stuff to the car and went back to
- At 11:00, I attended the workshop Writin' me a RUST about the programming language Rust. I left early. The slides were hard to read from the distance
were I was sitting.
- At 12:00, I listened to the presentation OpenStreetMap for beginners by Pieter Vander Vennet. Slides. Recording.
- At 13:16, I joined the queue for the badge. Not long after I joined, the
queue was closed and we were informed that we would not get a tested badge.
While in the queue someone was handing out HD1107O Seven-segment displays and I also got one.
- At 14:25, after answering some questions with respect to the safety
issues of the 18650 cells, I received my partly assembled WHY2025 badge with a paper bag with the remaingin parts. I opted out
on receiving the two 18650 cells.
- At 15:28, before the closing by NanCY BEeRs and Boekenwuurm, I left for home.
Some photographs from the camp.
Orga Pictures and some collections on
wiki. On Flickr.
33.9° Celsius
The temperature at Twenthe Airport has gone up to
33.9° Celsius, which breaks the previous record of 33.8° on this date last year.
32.3° Celsius
The temperature at Twenthe Airport has gone up to
32.3° Celsius, which breaks the previous record of 32.1° on this date three year ago. The latest prediction is that the temperature
will get over 25° tomorrow, which means that we will have a second heat
wave according to the official Dutch definition.
Catalogue
At 14:41, I received the catalogue Prospects & Concepts edited by
Mirjam Beerman, written in Dutch and published by Mondriaan Fonds on Thursday,
February 8, 2018, which I had bought on Monday, August 18, 2025 at 12:08:48
from KUNZT.NL for € 5.00.
At TkkrLab, I soldered a connector for a LoRa antenna on the WHY2025 badge. Last
Saturday, I tried to assemble the basge, but then I discovered that I first had
to solder the connector for the antenna. I was warned to be carefull during the
soldering with two of the five pins that are rather close to the display as not
to harm the display with the heat.
snprintf
The function snprintf is used in C to print some formatted text into a string
buffer with a specified size. Basic strings in C are zero terminated, which
mean that the end of a string is indicated with a zero character. That zero
character is not considered as part of the string itself. This means you always
have to reserve one additional character if you want to deal with a string of a
certain length. (It is a known source of off-by-one errors.) There are also alternative ways to represent a string
of variable length and that is to have a field that specifies the number of
characters in the string. I remember that (in some dialect of) Pascal strings were presented in this way (and could not be longer than
255 characters). I had the idea that if you let snprintf 'print' a
text that is longer than the size of the buffer that it would not place a zero
termination character in the last position of the buffer and that you had to
do this yourself. Today, I learned that this is not the case, the function does
place a zero character either at the end of the string to be printed if it fits
in the given size, or otherwise at the last location of the buffer, except when
the size is zero, in which case it does not print anything at all. The function
always returns the number of characters that it would have printed if the size
of the buffer would have been large enough. This allows you to check if the
printed string was actually terminated or allows you to know how large the
buffer should have been to print the given text. It took me some time to
figure out why I was mistaken about this aspect of the snprintf
function. It appeared that Microsoft Visual Studio for a long time did not add the zero character
as described in the Remarks section of the page about the function for Visual Studio 2022.
Citizen of the Galaxy
I read that an animated
movie is going to be made from the book Citizen of the Galaxy by Robert A. Heinlein. 'The project hails from
prolific animation director Jay Oliva and his Lex+Otis banner,' it says in the article from The Hollywood Reporter. Furthermore, the article writes:
'The script is already written, and the team is far into the visual development
for the film. It is now discussing casting as it eyes a 2027 theatrical
release.' I have read the book four times,
three times in Dutch and one time in English in 1977, 1982, 2009, and 2013. It is a rather complex story to be cramped into a single
movie and would require quite a bit of world building as the main protagonist
goes through four very different social environments. I very much would have
a peek at the script to know what is in and what is not. I doubt it will have
the interaction where the free traders trade items of pornography from the
bachelor's quarters agains carved jewels with some aliens. I am definitely
looking forward to this movie. (Audio book on YouTube.)
Cold record
The temperature at Twenthe Airport dropped to
4.6° Celsius (or even 4.4° according to one source) breaking the cold
record of 4.9° from 2005 for this day of the year. At the ground the
temperature dropped to 0.3°. There are some places were it dropped to
-0.3° making this the first night with ground frost in the Netherlands,
which is exceptional earlier. From what I heard on the news, these cold
temperatures are the results of a clear sky in combination with almost no
wind and cold temperatures in the upper atmosphere. I guess that those cold
temperatures are the result from the wind coming from the North in the past
week. I get the impression that the jet stream has been rather chaotic around
Europe with winds blowing South from the polar region instead of blowing West.
Cold record
The temperature at Twenthe Airport dropped to
4.1° Celsius (or even 3.8° according to one source) breaking the cold
record of 4.8° from 1989 for this day of the year. At the ground the
temperature dropped to 0.6°. There are some places were it dropped to
0.0°.
Drawing fractal with arcTo
In preperation for a talk that I plan
to give on Hackfest 2025 about fractal jigsaw
puzzles, I wrote some JavaScript code that
uses the arcTo function to draw arcs with the use of two points, because it is
somewhat easier to use when you have to draw an arc direction indicated with
some vector, because you do not need to calculate the start and end angles of
the arc as you have to do with the arc function. The arc function is easier to use if you want to draw a
circle or a part of a circle if you do know the start and end angles.
Going into the city
It has been four weeks since I went into the city. At Fotogalerie Objektief I saw the exhibition
'Frameless Identities' by Hartenjager also known as Sanne Wijdenes. I already saw some of her
work on Tuesday, March 18. She has an
interesting technique of mixing images with various techniques. I walked the
usual round through the city and bought a soft ice cream.
This months interesting links
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