Hello, world!

Signing a file:

jookia@titan:~/gitsshkey% ssh-keygen -Y sign -n file -f ~/.ssh/id_ed25519_sk_solo -I 'jookia' TEST_FILE
Signing file TEST_FILE
Enter PIN for ED25519-SK key: 
Confirm user presence for key ED25519-SK SHA256:/gEvgms/9HpbgpcH+K7O4GYXmqkP7siJx9zHeEWRZTg
TEST_FILE.sig already exists.

Verifying a file:

jookia@titan:~/gitsshkey% cat allowed_signers
jookia sk-ssh-ed25519@openssh.com AAAAGnNrLXNzaC1lZDI1NTE5QG9wZW5zc2guY29tAAAAID7OzA3dl0YNrkRPXGldZTzz3rtFcyBvXz661ZmMgIS3AAAABHNzaDo= jookia@titan
jookia@titan:~/gitsshkey% ssh-keygen -Y verify -n file -f allowed_signers -s TEST_FILE.sig -I 'jookia' < TEST_FILE
Good "file" signature for jookia with ED25519-SK key SHA256:/gEvgms/9HpbgpcH+K7O4GYXmqkP7siJx9zHeEWRZTg

Signing a git commit:

jookia@titan:~/gitsshkey% git config commit.gpgsign true
jookia@titan:~/gitsshkey% git config gpg.format ssh
jookia@titan:~/gitsshkey% git config user.signingkey "~/.ssh/id_ed25519_sk_solo"
jookia@titan:~/gitsshkey% git commit --amend
Enter PIN for ED25519-SK key: 
[main ffd9e50] Add TEST_FILE and signature
 Date: Tue Jan 25 10:49:19 2022 +1100
 4 files changed, 28 insertions(+)
 create mode 100644 TEST_FILE
 create mode 100644 TEST_FILE.sig
 create mode 100644 allowed_signers

Verifying a git commit:

jookia@titan:~/gitsshkey% cp allowed_signers .git/tofu_signers
jookia@titan:~/gitsshkey% git config gpg.ssh.allowedSignersFile .git/tofu_signers
jookia@titan:~/gitsshkey% git log --oneline --show-signature
ffd9e50 (HEAD -> main) Good "git" signature for jookia with ED25519-SK key SHA256:/gEvgms/9HpbgpcH+K7O4GYXmqkP7siJx9zHeEWRZTg
Add TEST_FILE and signature
22898e2 Initial commit