Jay meangrape

Setting up ssh public key authentication on macOS using a YubiKey 4

I largely followed Florin's blog post, but have a few notes to add regarding issues I encountered:

I used a YubiKey 4, while the blog describes using a YubiKey NEO. I'm sure a YubiKey 5 would also work. I'm also running macOS 10.13.6.
I installed GPGTools as recommended. However, as I'll note later, it seems that gpg-agent only automatically starts when gpg is used; for ssh, you'll need to ensure it's running.
Before generating your keys, decide what key size you want to use. If you run the list command inside gpg --edit-card, look for the Key attributes line to see what is currently selected. On my YubiKey 4, it defaulted to 2048 bits for all keys:

Key attributes ...: rsa2048 rsa2048 rsa2048

This text is the section about OS X Yosemite (which also works for macOS Sierra) from https://docs.basho.com/riak/kv/2.1.4/using/performance/open-files-limit/#mac-os-x

The last time i visited this link it was dead (403), so I cloned it here from the latest snapshot in Archive.org's Wayback Machine https://web.archive.org/web/20170523131633/https://docs.basho.com/riak/kv/2.1.4/using/performance/open-files-limit/

"Jazz Improvisation and Organizing: Once More from the Top" http://web.cba.neu.edu/~mzack/articles/jazzorg/jazzorg.htm

"Supporting Improvisation Work in Inter-Organizational Crisis Management"

	#!/usr/bin/env python3

	import fdb
	import json
	from argparse import ArgumentParser
	import logging
	import signal
	import sys
	import tempfile
	from prometheus_client import (

	# This was only tested against revision ac2d18a7353cd3ac1ba4b5993f2776fe0c5eedc9
	# of https://gitlab.haskell.org/ghc/ghc
	let
	nixpkgs = builtins.fetchTarball {
	url = "https://github.com/NixOS/nixpkgs/archive/7e003d7fb9eff8ecb84405360c75c716cdd1f79f.tar.gz";
	sha256 = "08y8pmz7xa58mrk52nafgnnrryxsmya9qaab3nccg18jifs5gyal";
	};

	config.allowBroken = true;

	import itertools

	import random
	import fdb

	from functools import partial

	import time

	from multiprocessing import Pool

	# Put in your ~/.ssh/config

	### Problem
	#
	# You are on a public WiFi network that blocks SSH ports but you don't want to switch
	# to pushing your Github changes to GH remotes via HTTPS nor do you want to change the
	# remote hostname in all your repos.

	Host github.com
	Hostname ssh.github.com

	#!/bin/bash

	# FZF_DEFAULT_COMMAND utility for fzf
	#
	# Tries to use Watchman, Ripgrep (rg), The Silver Searcher (ag) in this order.
	# ...or falls back the fzf's Unix default.
	#
	# TODO:
	# - Use 'git ls-files -cmod' in Git repositories

	function killport {
	echo '🚨 Killing all processes at port' $1
	lsof -ti tcp:$1 \| xargs kill
	}