infra: Arch Linux servers automation infrastructure for cjprods.org

The goal is to automate the configuration of Arch Linux servers
at cjprods.org.

• Utilize systemd to its full potential.
  • Socket activation
  • Generators (dynamic unit files and drop-ins)
  • Compartmentization (security sandboxing, DynamicUser, etc.)
  • Only requires a Stateless System
• Utilize pacman (alpm, Arch Linux Package Manager) to its full potential.
  • alpm hooks
• Use GitHub Release as an Arch Linux repository.
• Support for hiding secrets for certain situations (like passwords and keys).
• Reusable: Everyone can setup their own automation based on this project.
  • Keep as most things in plaintext as possible.
    Only sensitive parts (passwords, open ports, etc.) are encrypted.
  • Every encrypted file secret-* has a corresponding
    example plaintext file example-secret-*.

Setup pacman for local access

# /etc/pacman.conf
[infra]
SigLevel = Optional TrustAll
Server = https://cjprods.org/infra-repo

Setup a new server

Setup pacman for packages

# /etc/pacman.conf
[infra]
SigLevel = Optional TrustAll
Server = https://github.com/cjxgm/infra/releases/download/latest

Prepare private key

Put the private key as secret.pem, then package the private key:

make makepkg-private-key

Upload and install the private key package build/repo/infra-private-key-*.pkg.tar.xz manually.

Now, pacman -Syu, then install any wanted packages.
All packages provided by this repo has a prefix of infra-.

Setup git for accessing secrets

• Put the private key in secret.pem.
• Run make setup.
• After editing secret-* files, it’s better (for now) to
  run make unsetup to cancel the effect
  so that rebasing won’t conflict that much.

About various keys

• The private key is used for encrypting the decryption key.
• The encrypted decryption key is secret.key.
• The decryption key (with the private key) is used to decrypting secrets.