Just a small finger exercise …
Articles in Category "Technik"
There is no such Thing as „End-to-End-Encryption“
13. Dezember 2020 in Gesellschaft, Technik.
A communication between two communication partners, which on a technical level can also be called „endpoints“ or „ends“ of a connection (or more general, of a channel of communication), is either encrypted, or it is not. If somewhere in between the „ends“ of the connection, encryption takes place, such that there exist parts of the […]
Bourne to Bourne Again Shell Forward Compatibility
20. August 2023 in GNU/Linux, Programmierung.
Introduction In this article i try to find out, if Bourne Shell scripts are runnable in Bourne Again Shell without modification. If not, i advice on how to modify the code so that it runs on both Shells. An interpreter for some variant of Bourne Shell is available as an executable /bin/sh on most Linux […]
Comparing Distinguished LDAP Names
6. August 2020 in Administration, GNU/Linux, Programmierung.
In a Bourne Shell script, a distinguished name (DN) for performing an LDAP-query is held in a variable: dn=“cn=Malmø,ou=County Capitals,dc=Sweden,dc=Europe“ For the purpose of demonstration, this example DN contains a non-ASCII character. Let’s write a Bourne Shell function that escapes such special characters as requested by RFC 4514 using perl’s Net::LDAP::Util: canonical_dn() { perl -s […]
Determining User Access on a Linux Filesystem with „Classic Permissions“
30. November 2021 in Administration, GNU/Linux.
Introduction Looking at a Linux filesystem, checking if a certain file or directory is accessible for reading, writing or executing by certain users or groups poses interesting challenges. Let the basic and seemingly simple question be: „Given a user X and a file Y, can it be determined if X has access to Y, and […]
AD-Precreation using ktutil, kinit and adcli
4. Dezember 2019 in Administration, GNU/Linux.
Using computer object precreation you can enable machines to join an Active Directory domain with knowledge of just one dedicated one-time-password. Combined with delegation you can offload management of computer objects to an otherwise unprivileged AD user.
Drawing a Yellow Rectangle on Android
26. November 2021 in Programmierung.
As an addendum to my previous article, there now also is an Android App „YellowRectangle“ that draws a yellow rectangle and terminates on the first touch event. It runs on Android version 4.0.3 (Ice Cream Sandwich MR1) and upward. It is written in Java and C++ and uses the Allegro game development library (http://liballeg.org/).
Drawing A Yellow Rectangle
25. März 2018 in Programmierung.
Premise On the weekend i wanted to perform the task of drawing a yellow rectangle programmatically onto the screen of a Personal Computer: The program would feature a viewport that occupies the entirety of the primary display of the PC. On the viewport, 640 pixels could be adressed in width, 480 in height. The viewport […]