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@timothyham
timothyham / ipv6guide.md
Last active July 17, 2024 13:27
A Short IPv6 Guide for Home IPv4 Admins

A Short IPv6 Guide for Home IPv4 Admins

This guide is for homelab admins who understand IPv4s well but find setting up IPv6 hard or annoying because things work differently. In some ways, managing an IPv6 network can be simpler than IPv4, one just needs to learn some new concepts and discard some old ones.

Let’s begin.

First of all, there are some concepts that one must unlearn from ipv4:

Concept 1

@kconner
kconner / macOS Internals.md
Last active July 7, 2024 19:42
macOS Internals

macOS Internals

Understand your Mac and iPhone more deeply by tracing the evolution of Mac OS X from prelease to Swift. John Siracusa delivers the details.

Starting Points

How to use this gist

You've got two main options:

@Earnestly
Earnestly / posix-issue8.md
Last active June 22, 2024 15:43
A Selected List of Additions and Changes Coming With POSIX Issue 8

A Selected List of Additions and Changes Coming With POSIX Issue 8

Last major change: 10th March 2023

New Commands

Additions

@romkatv
romkatv / srand32.zsh
Last active May 4, 2024 05:04
srand32.zsh
# Returns a random 32-bit number.
# If /dev/urandom is cryptographically secure, so is srand32.
#
# If zsh is compiled with 64-bit number support, the result
# is non-negative. Otherwise it may be negative and the value
# is governed by the rules of unsigned-to-signed conversion in C.
#
# Examples:
#
# % print -r -- $(( srand32() ))
@cutiful
cutiful / mastodon-ip.md
Last active March 21, 2024 04:00
Detecting the real IP of a Cloudflare'd Mastodon instance

Detecting the real IP of a Cloudflare'd Mastodon instance

NB: This will not work for instances that proxy outgoing requests!

Reading the docs

I wanted to find a way to detect the real IP address of a Mastodon/Pleroma/Misskey/etc instance hosted behind Cloudflare. How to do that? Well, it's federated, which means I can probably get it to send a request to a server of mine! And how to do that? I tried reading the ActivityPub spec. The following caught my attention:

Servers should not trust client submitted content, and federated servers also should not trust content received from a server other than the content's origin without some form of verification.

@larryv
larryv / x86docssync
Last active January 16, 2023 03:52
A macOS shell script for syncing the kib.kiev.ua/x86docs documentation archive
#!/bin/sh
# x86docssync - Syncs documents from kib.kiev.ua/x86docs
#
# Written in 2020, 2022 by Lawrence Velázquez <vq@larryv.me>.
#
# To the extent possible under law, the author(s) have dedicated all
# copyright and related and neighboring rights to this software to the
# public domain worldwide. This software is distributed without any
# warranty.
@dhh
dhh / tracker_blocking.rb
Last active June 30, 2024 14:35
Current list of spy pixels named'n'shamed in HEY, as of April 23, 2020
module Entry::TrackerBlocking
extend ActiveSupport::Concern
included do
has_many :blocked_trackers
end
email_service_blockers = {
"ActiveCampaign" => /lt\.php(.*)?l\=open/,
"AWeber" => "openrate.aweber.com",
@rjhansen
rjhansen / keyservers.md
Last active April 14, 2024 12:28
SKS Keyserver Network Under Attack

SKS Keyserver Network Under Attack

This work is released under a Creative Commons Attribution-NoDerivatives 4.0 International License.

Terminological Note

"OpenPGP" refers to the OpenPGP protocol, in much the same way that HTML refers to the protocol that specifies how to write a web page. "GnuPG", "SequoiaPGP", "OpenPGP.js", and others are implementations of the OpenPGP protocol in the same way that Mozilla Firefox, Google Chromium, and Microsoft Edge refer to software packages that process HTML data.

Who am I?

@lizthegrey
lizthegrey / attributes.rb
Last active February 24, 2024 14:11
Hardening SSH with 2fa
default['sshd']['sshd_config']['AuthenticationMethods'] = 'publickey,keyboard-interactive:pam'
default['sshd']['sshd_config']['ChallengeResponseAuthentication'] = 'yes'
default['sshd']['sshd_config']['PasswordAuthentication'] = 'no'
:xdg-support: https://wiki.archlinux.org/index.php/XDG_Base_Directory
:xdg-spec: https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html
:fhs: https://en.wikipedia.org/wiki/Filesystem_Hierarchy_Standard
:madness: http://pub.gajendra.net/2012/09/dotfiles
:litter: https://www.reddit.com/r/linux/comments/971m0z/im_tired_of_folders_littering_my_home_directory/
:systemd: https://www.freedesktop.org/wiki/Software/systemd/
:systemd-fhs: https://www.freedesktop.org/software/systemd/man/file-hierarchy.html
:systemd-fhs-bin: https://www.freedesktop.org/software/systemd/man/file-hierarchy.html#~/.local/bin/
:toc: macro