Vladimir Kotal vladak

SSH + Yubikeys via FIDO2 on MacOS

Resources

Prerequisites

Yubikey firmware should be >5.2.3

Initial checks

Start by checking that there aren't any previous ssh keys inside the FIDO2 authenticator of your YubiKey. You can check if they exist by running the command below:

nix shell nixpkgs#yubikey-manager -c ykman fido credentials list

If the command above outputs a string mentioning "ssh" or "openssh", then you have already got a key generated and store on your YubiKey.

Evaluating additional authentication factors

Before generating a new ssh key to store on your YubiKey you must consider which additional required authentication factors you want to use. Below you can see a table with the available factors and their corresponding command:

Fixing MacMini 2012 Platform Controller Heatsink gap

Intel HM77 (SLJ8C) platform controller hub

I measured the gap to be just a little bit higher than 0.15mm (I couldn’t fit the 0.2 filler gauge). So I tried to shim it with something, aluminum foil is definitely not enough you would need more than 10 layers. So the closest thing I had was a Coke can, I cut a square piece and remove the paint and inner coating with steel wool, trim it to 14x14mm.

it turned out to be 0.1mm, (don’t use 2 layers it will be too thick). add thermal paste to both sides. So the thermal paste only has to fill a gap about 0.025 on each side instead of a massive 0.2 gap.

Here's a list of mildly interesting things about the C language that I learned mostly by consuming Clang's ASTs. Although surprises are getting sparser, I might continue to update this document over time.

There are many more mildly interesting features of C++, but the language is literally known for being weird, whereas C is usually considered smaller and simpler, so this is (almost) only about C.

1. Combined type and variable/field declaration, inside a struct scope [https://godbolt.org/g/Rh94Go]

struct foo {
   struct bar {
 int x;

Install `pigpio`

If you're working with the rpi3's gpio, the pigpio library can be very handy.

sudo apt-get update
sudo apt-get install pigpio

If you also want to access pigpio from python, install: sudo apt-get install python-pigpio python3-pigpio

Setup `pigpiod` service to run at boot

collapsible markdown?

CLICK ME

yes, even hidden code blocks!

print("hello world!")

Attack of Pythons

Among computer programmers, a “gotcha” has become a term for a feature of a programming language that is likely to play tricks on you to display behavior that is different than what you expect.

Just as a fly or a mosquito can “bite” you, we say that a gotcha can “bite” you. So, let's proceed to examine some of Python's gotchas !

	# SPDX-FileCopyrightText: 2023 anecdata
	#
	# SPDX-License-Identifier: MIT

	import json
	import microcontroller
	import supervisor

	from ⚙️ import *

	# Instructions:
	#
	# 1. Save this file as `{root}/.github/workflows/cicd.yml`.
	# 2. Set the `PYPI_USER` and `PYPI_PASS` secrets in your GitHub CI config.
	# 3. Update the `PYPACKAGE_NAME` declaration to the name you want to use in PyPi.
	#
	# Public Gist: https://gist.github.com/aaronsteers/f3eec4db94d3db1de78b76b3318e9e33

	name: Python CI/CD
	env:

	- translate all the slide/notes up to and excluding sem API (Vlada)
	- translate all the remaining slides for sem API (Jan)
	- move System V semaphore API to the appendix, do not translate (Jan)
	- change System V sem API in the Syllabus to POSIX sem API (Vlada)