2022-06-13 22:42:04 +00:00
|
|
|
---
|
|
|
|
title: Signing Commits with GPG
|
|
|
|
author: Al Bowles
|
|
|
|
revision_date: 2022-06-13
|
|
|
|
rc:
|
|
|
|
prod: Rocky Linux
|
|
|
|
ver: 8
|
|
|
|
level: Final
|
|
|
|
---
|
|
|
|
# Creating your primary keypair
|
2022-06-13 22:55:39 +00:00
|
|
|
Initiate the keypair generation wizard
|
2022-06-13 22:42:04 +00:00
|
|
|
|
|
|
|
gpg --full-generate-key --expert
|
|
|
|
|
2022-06-13 22:55:39 +00:00
|
|
|
Select option `(9) ECC and ECC` for the key type
|
|
|
|
Select option `(1) Curve 25519` for the elliptic curve
|
|
|
|
Set a validity period of your choice, ideally less than 1 year
|
2022-06-13 22:42:04 +00:00
|
|
|
Specify real name and email address to associate with this keypair
|
2022-06-13 22:55:39 +00:00
|
|
|
Type a passphrase (twice)
|
2022-06-13 22:42:04 +00:00
|
|
|
|
|
|
|
# Create a signing keypair
|
|
|
|
Add a signing subkey
|
|
|
|
|
|
|
|
gpg --edit-key my@email.addr
|
|
|
|
gpg> addkey
|
|
|
|
[ passphrase ]
|
|
|
|
|
|
|
|
Select [ECC] (sign / authenticate / encrypt?) for kind of key, 4096 bits, valid for 180d
|
|
|
|
|
|
|
|
gpg> save
|
|
|
|
|
|
|
|
Create revocation certificate
|
|
|
|
|
|
|
|
gpg --output \<my@email.addr\>.gpg-revocation-certificate --gen-revoke my@email.addr
|
|
|
|
|
|
|
|
# Back up your keypair
|
|
|
|
Export the *primary keypair* (put these somewhere very safe along with revocation certificate)
|
|
|
|
|
|
|
|
gpg --export-secret-keys --armor my@email.addr > \<my@email.addr\>.private.gpg-key
|
|
|
|
gpg --export --armor my@email.addr > \<my@email.addr\>.public.gpg-key
|
|
|
|
|
|
|
|
# Remove the *primary keypair* from your keyring
|
|
|
|
Export all subkeys from the new keypair to a file - use ramfs instead of tmpfs/ or /dev/shm/ because ramfs doesn't write to swap
|
|
|
|
|
|
|
|
mkdir /tmp/gpg
|
|
|
|
sudo mount -t ramfs -o size=1M ramfs /tmp/gpg
|
|
|
|
sudo chown $(logname):$(logname) /tmp/gpg
|
|
|
|
gpg --export-secret-subkeys my@email.addr > /tmp/gpg/subkeys
|
|
|
|
|
|
|
|
Delete original signing subkey from keypair in our keyring
|
|
|
|
|
|
|
|
gpg --delete-secret-key my@email.addr
|
|
|
|
|
|
|
|
Re-import the previously exported keys
|
|
|
|
|
|
|
|
gpg --import /tmp/gpg/subkeys
|
|
|
|
sudo umount /tmp/gpg
|
|
|
|
rmdir /tmp/gpg
|
|
|
|
|
|
|
|
Look for `sec#` instead of `sec` in the output - pound sign means signing subkey is *not* in the keypair located in the keyring
|
|
|
|
gpg --list-secret-keys $HOME/.gnupg/secring.gpg
|
|
|
|
|
|
|
|
# Revoking a *signing keypair*
|
|
|
|
Find the *primary keypair* and import it (preferably into an ephemeral system like a liveUSB)
|
|
|
|
|
|
|
|
gpg --import /path/to/\<my@email.addr\>.public.gpg-key /path/to/\<my@email.addr\>.private.gpg-key
|
|
|
|
gpg --edit-key my@email.addr
|
|
|
|
gpg> revkey
|
|
|
|
[ passphrase twice ]
|
|
|
|
gpg> save
|
|
|
|
|
|
|
|
|
|
|
|
# Renew an expired or expiring keypair
|
|
|
|
|
|
|
|
gpg --edit-key my@email.addr
|
|
|
|
[select a key]
|
|
|
|
gpg> expire
|
|
|
|
[specify an expiration]
|
|
|
|
gpg> save
|
|
|
|
|
|
|
|
# Create a single signed git commit
|
|
|
|
|
|
|
|
git commit -S -m "my awesome signed commit"
|
|
|
|
|
|
|
|
# Configure git to always sign commits with a specified key
|
|
|
|
|
|
|
|
$ gpg --list-secret-keys --keyid-format=long # grab the fingerprint from the 'sec' line
|
|
|
|
git config [--global] commit.gpgsign true
|
|
|
|
git config [--global] user.signingkey DEADB33FBAD1D3A
|
|
|
|
|
|
|
|
# Configure VSCode to sign commits
|
|
|
|
|
|
|
|
# User or workspace setting
|
|
|
|
"git.enableCommitSigning": true
|
|
|
|
|
|
|
|
# References
|
|
|
|
[OpenPGP Best Practices](https://riseup.net/en/security/message-security/openpgp/best-practices#key-configuration)<br>
|
|
|
|
[Github: Signing Commits](https://docs.github.com/en/enterprise-server@3.5/authentication/managing-commit-signature-verification/signing-commits)<br>
|
|
|
|
[Braincoke's Log: Create a GPG Key](https://blog.braincoke.fr/security/create-a-gpg-key/)<br>
|
|
|
|
[Creating the Perfect GPG Keypair](https://alexcabal.com/creating-the-perfect-gpg-keypair)<br>
|
|
|
|
[Digital Neanderthal: Generate GPG Keys With Curve Ed25519](https://www.digitalneanderthal.com/post/gpg/)<br>
|