The OpenSSH client has a lot of very powerful features for tunneling applications through a SSH connections and is one of my favorite tools for quick-and-dirty network plumbing tasks. It can be very useful for fixing/bypassing connectivity issues (caused by NATs, firewalls), accessing internal networks. This post is an overview of the different tunneling options available in OpenSSH. This is inteded as a reference to use when I am explaining (every so often) how to use SSH for tunneling.

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Tutorial on how to get Carte Professionnel de Santé 3 (CPS3) smart cards work with Firefox under Linux with a Kap&Link smart card reader. It has some information to understand the related lingo, how the different components interact and how you might try to enable support for a PC/SC (Personal computer/Smart Card) / CCID (Chip/Smart Card Interface Devices) smart card reader which is not supported by the driver.

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Some commands for interacting with the namespaces of Podman containers.

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Some notes about using the TUN/TAP interface, especially on Linux.

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Some notes on ELF 🧝 loading and dynamic linking mainly for GNU userland (ld.so, libc, libdl) running on top of the Linux kernel. Some prior knowlegde on the topic (virtual memory, shared objects, sections) might be useful to understand this.

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In an attempt to simplify the development around the SimGrid model-checker, we were thinking about moving the model-checker out in a different process. Another different approach would be to use a dynamic-linker isolation of the different components of the process. Here is a summary of the goals, problems and design issues surrounding these topics.

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