David Sulc davidsulc

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:

"What the heck is a Yubikey and why did I buy one?": A user guide

(EDIT: Besides Reddit, I've also put this up on Github Gist)

So while looking for information on security keys before getting one myself, I got very confused reading about all the different modes and advertised features of Yubikeys and other similar dongles. The official documentation tends to be surprisingly convoluted at times, weirdly organized and oddly shy about a few of the limitations of these keys (which I'm making a point of putting front and center). Now that I have one, I decided to write down everything I figured out in order to help myself (and hopefully some other people reading this) make sense of all this.

Since I'm partly writing these notes for myself, there might be some back and forth between "exp

Exporting your 2FA tokens from Authy to transfer them into another 2FA application

IMPORTANT - Update regarding deprecation of Authy desktop apps

Past August 2024, Authy stopped supported the desktop version of their apps:
See Authy is shutting down its desktop app | The 2FA app Authy will only be available on Android and iOS starting in August for details.

And indeed, after a while, Authy changed something in their backend which now prevents the old desktop app from logging in. If you are already logged in, then you are in luck, and you can follow the instructions below to export to tokens.

If you are not logged in anymore, but can find a backup of the necessary files, then restore those files, and re-install Authy 2.2.3 following the instructions below, and it should work as expected.

Install Rails 3.1

gem install rails

generate new app, skipping Test::Unit file generation

rails new my_app -T

Set up Gemfile

Install Rails 3.1 RC

gem install rails --pre

generate new app, skipping Test::Unit file generation

rails new my_app -T

	class API::V1::BaseController < ApplicationController

	skip_before_filter :verify_authenticity_token

	before_filter :cors_preflight_check
	after_filter :cors_set_access_control_headers

	def cors_set_access_control_headers
	headers['Access-Control-Allow-Origin'] = '*'
	headers['Access-Control-Allow-Methods'] = 'POST, GET, PUT, DELETE, OPTIONS'

	<!DOCTYPE html>
	<html lang='en'>
	<head>
	<meta charset='utf-8'>

	<title>dc.js Experiment</title>

	<script src='js/d3.v3.js' type='text/javascript'></script>
	<script src='js/crossfilter.js' type='text/javascript'></script>
	<script src='js/dc2.js' type='text/javascript'></script>

	<script id="modal-view-template" type="text/html">
	<div class="modal-header">
	<h2>This is a modal!</h2>
	</div>
	<div class="modal-body">
	<p>With some content in it!</p>
	</div>
	<div class="modal-footer">
	<button class="btn">cancel</button>
	<button class="btn-default">Ok</button>

	ActionView::Base.field_error_proc = Proc.new do \|html_tag, instance\|
	html = %(<div class="field_with_errors">#{html_tag}</div>).html_safe
	# add nokogiri gem to Gemfile
	elements = Nokogiri::HTML::DocumentFragment.parse(html_tag).css "label, input"
	elements.each do \|e\|
	if e.node_name.eql? 'label'
	html = %(<div class="clearfix error">#{e}</div>).html_safe
	elsif e.node_name.eql? 'input'
	if instance.error_message.kind_of?(Array)
	html = %(<div class="clearfix error">#{html_tag}<span class="help-inline"> #{instance.error_message.join(',')}</span></div>).html_safe

	// ==UserScript==
	// @name Google Dictionary
	// @namespace http://byteco.de
	// @include *
	// ==/UserScript==

	var t = '';
	function gText(e) {
	t = (document.all) ? document.selection.createRange().text : document.getSelection();
	t = t.replace(/^\s+\|\s+$/g,"");