yubikey-pgp

Easily use your Yubikey with git and ssh without manual configuration: yubikey-pgp is a wrapper for OpenPGP operations with your YubiKey without having to deal with gpg.

Installation

If you put your binaries in ~/.local/bin:

PREFIX="$HOME/.local" make install

Usage

There are three main operations you might want to do with your YubiKey. First the least important: ykpgp reset resets all OpenPGP data on your YubiKey, but does not touch the other functions on it.

Then there's init and register. init is for when your YubiKey is new, and you want to make sure it is initialized with keys. The purpose of register is setting up your system to use keys that are already on your YubiKey. Setting up your system is also done by init, so you don't need to run ykpgp register after ykpgp init.

These two subcommands have a few options in common:

• -n Use temporary GNUPGHOME. Mostly for testing
• -i <uid> Add uid (e.g., name <mail@example.com) to key. Can be specified multiple times. First is primary. If none are given, default is "$NAME <$EMAIL>"
• -g Set up open git repository for commit signing
• -G Set up git for commit signing
• -s Add key to possible ssh identities, and set up your shell profile so ssh uses gpg.

init also has the option (for more advanced users) to use keys from the GPG keyring using -k. This almost invariably results in the actual key data being removed from the keyring, so if you go this route, make sure you have backups. ykpgp leaves the key data in place, but even a simple gpg --card-status will remove it. So if you want to have the same key data on multiple YubiKeys, immediately remove the YubiKey after initializing and initialize the next one.