John Kr is a small business owned by Elger Jonker, an ethical hacker from The Netherlands.
I’m currently active in organizing MCH2022, python development for internet.nl, basisbeveiliging.nl and various other projects. I also perform web-pentests at irregular intervals for applications that contain sensitive (medical) data.
All information below is severely outdated, because time and reasons.
You can contact me at elger@…
Regards,
Elger
Conference Speaker
Twilight-CD @ OHM2013
Media Archeology: Dissecting an extremely popular monthly software series “Twilight”. Making millions, a strong brand, and not getting caught. This is what i found out dissecting the most beautifully designed illegal software series in the Netherlands.
The picture shows that scratching out a hologram does not work.
View the presentation: https://www.youtube.com/watch?v=A8U7qnI6ngw
Session Management @ EMF2014
EMF2014 was a hacker conference in the United Kingdom. My lecture was about developing perfect session management in privacy sensitive web applications. All Dutch speakers wore Orange suits to represent The Netherlands in an awfully tacky way.
Watch the talk: https://www.youtube.com/watch?v=-kEhvoS6HV0
Community Building @ OpenSuse2015
Community building at nerd level difficulty. The only question that you need to ask yourself is “why”, a concept introduced by Simon Sinek. Applying this logic to OpenSuse (and many others), i could not find why i would like to join it… which is a challenge for this community. Best part after 10:00.
Watch the talk: https://www.youtube.com/watch?v=odEwPM-u7cg
Mediawiki innovations
Projects Showcase
Any hackerspace has a lot of projects going on. To show what is happening at Hack42, a project page has been created, together with a list of projects. The list shows images of projects and allow multiple users per project. The projects are presented polaroid style.
This approach has been copied to other wiki’s such as the hackerspace Nurdspace.
Mentioned Users
With the {{MentionedUser|username}} template, information from the userpage is retrieved. It shows the profile image, projects and interests of the user. This template helps getting to know the members at Hack42.
This approach has been copied to other wikis, such as the Hackerspace Frack wiki.
Built with MediaWiki
Team Overview
This dynamic overview allows teams to specify the number of members they need and shows who are the first line contacts.
Team Meetings
Teams can plan meetings in the wiki, which are placed on a calendar and syndicated to rss and ical.
Navigation Boxes
The bottom of a series of pages contains this navigation menu. It is a lightweight clone of the official menu of Wikipedia, without the need for the LUA scripting environment. It is built with CSS and wiki-syntax. No plugins or javascript needed.
User Page
User pages contain a picture, interests, projects and other information placed on the wiki by a user. They are meant to be colorful and engaging.
Member list
The memberlist shows profile pictures and barcodes to be used at the Hack42 bar for purchasing products.
Activities list
Activities are available in iCal, RSS and on the wiki.
Instructions
Instructions help new wiki-users to create pages in a coherent fashion. The guide explains what to enter where.
Forms
Forms make it easy to fill in information, reducing a common anti-pattern called stonewalling: forcing new and enthusiastic users to read 40 pages of bureaucracy.
Statistics
Statistics can be derived from every aspect of a wiki. From the built-in statistics to custom statistics, shown here are numbers of projects, tools and more.
Side Menus
Side menus are ideal for navigation through a chapter. It is comparable to an index.
MediaWiki Management
SHA2017
SHA2017 is managed by statistics, which are gathered through the wiki. It is team-focussed and helps teams sharing information about vacancies and meetings. The whole world can see how a team is doing, which is a core value of SHA: transparency.
OHM2013
This wiki featured community news, just as the CCC2011 wiki did. It included a list of projects similar to Hack42.
https://ohm2013.org/wiki/ (offline)
Hack42
Hack42 was in need of an information sharing structure. Together with a fried we made the wiki usable, with lot’s of activities and projects to discover.
Additionally
Additionally:
- Four private, corporate, wiki’s.
- Frontpage of the CCC-2011 Camp wiki (as seen above).
Impact on the conferences
SHA2017
For SHA2017 i’ve initiated the project-management team dubbed the “Sanity” or “Projectleiding” team. This team has the main goal to organize this conference while being still able to have fun before, during and after the event. Our strategy is based on team redundancy and communication.
OHM2013
At OHM2013 i’ve been involved in producing Rainbow Island, a 2500 square meter gaming paradise. Additionally i’ve designed various scaffolding constructions, helped build their web-presence and have done various other things.
Hacker Hotel
A friend wanted to start a new hacker conference called “Hacker Hotel”. Together we’ve setup a wordpress site and worked out the concept. This is a yearly event in the Netherlands.
Picture: Hotel Overbosch, Garderen
IFCAT Foundation
Responsible for SHA2017, MCH2021 / MCH2022.
Internet Cleanup Foundation
Welkom!
Awesome Retro
I’ve founded the Awesome Retro foundation from scratch. Continuous and limitless dedication resulted in a group of friends that shared the same goal: retrogaming for everyone. It today visits the biggest festivals in all kinds of genres to bring retrogaming. It also has a public retro-gaming community location called Awesome Space. I’m proud to say that this foundation has made an impact on over half a million people in the Netherlands.
I’ve left the foundation in November 2015 to focus on security, ethical hacking and giving myself space to discover new frontiers.
Hack42
After the HAR2009 conference, hackerspaces started popping up in the Netherlands. First RandomData, then RevSpace. All i knew is that i had to do this. I jumped on board at the idea of Hack42, where i was the treasurer, helped with practical operations such as finding a location and set up policy.
I left Hack42 after two years to take care of the Awesome Retro foundation.
Twilight CD
In the Netherlands, before the age of internet, software piracy was done on physical media. The largest and highest quality production was Twilight-CD, which ran for years on end, with millions of copies sold. I’ve dissected this compilation, from artwork to bits and bytes on the cd-rom. It was featured on GeenStijl and is the leading resource on software piracy in The Netherlands. This research started after purchasing the domain, previously owned by the Twilight crew.
Flippo’s
Flippo’s (tazos, pogs) was the biggest collecting craze ever hitting the Netherlands. With 97% of all children collecting these disks, it was a major commercial success. I’ve collected everything i could find and published it on a website. As usual, this research goes to extreme lengths and has identified the majority of anything that was ever known about the Flippo.
The picture shows a sticker intended to be on the bag of crisps. http://flippos.info
Rave Radio
Rave Radio was a house radio show on Dutch public broadcast between 1992 and 1995 presented by Adam Curry and mixed by Ronald Molendijk. Me and and Ruud van der Klugt revived this show with a few episodes of our own and by digitizing hundreds of cassettes.
All episodes can now be listened to on YouTube, it truly is the golden era of house music.
The picture is a re-creation by Ruud of the original and obscure Rave Radio logo. We did not get permission of Veronica to publish it, so we used the anagram “Rave Icon”. http://raveradio.nl/
Greenpoint / CT2
Greenpoint was the commercial name for the CT2 network. It was a predecessor of GSM and allowed for wireless calling near a base station. Me and Sjors Gielen have collected a lot of greenpoint material including handsets, booklets, flyers and newspaper articles. We’ve placed everything online. The only working GreenPoint base station in the world is situated at Hackerspace Hack42.
My first research endeavor was into the Braun MTV Eurochart music cd’s. This was a brand of pirated music discs containing a selection of chart-hits. They where produced and sold illegally by the ten-thousands each month.
http://elgerjonker.nl (contains these articles, they will be moved to a separate site for clarity.)
Hacking tools
SafeHash
Safehash calculates hash values of any data given, while not sending it to a server. It is written in Javascript and has a cool and unique party-mode. This shows the colors the hashes provide, while the hash-input being extended infinitely on the beat.
Convert ALL the things
If you need a (series of) encoding or hashes of a string, this is the right tool for the job. It provides an infinite number of conversions and an ever growing number of transformations.
Additionally it does not send anything to the server. It is written in client-side javascript.
This tool helps me a lot when playing CTF or when figuring out what a value means.
http://convertallthethings.com
