Creating a GPG key and fixing terminal signing in Alacritty

I’ve recently set up GPG commit signing for Git, and ran into a few annying issue when using Alacritty as my terminal. Here’s a step-by-step log of what I did, what broke, and how I fixed it.

Step 1 : Creating the GPG Key

gpg --full-generate-key

• Key type: ECC -> Curve 25519
• Usage: Signing + Authentication
• Expiry: 3 years
• UID: Name and emails
• Passphrase: yes

To list the key’s ID :

gpg --list-secret-keys --keyid-format LONG

Step 2 : Exporting the key for GitHub

gpg --armor --export mail

Full block must be pasted as it is, do not add or remove blank line.

Step 3 : Tellig Git to use this key

git config --global user.signingkey KeyID

Commits can be signed automatically with

git config --global commit.gpgsign true

Signing failed in Alacritty

I got the following error while trying to commit

git commit -S -m "commit message"
gpg: signing failed: Inappropriate ioctl for device
gpg: [stdin]: clear-sign failed: Inappropriate ioctl for device
gpg: signing failed: Operation cancelled

Reason :

Pinentry (the program asking for my secret’s key passphrase), was trying to use an interface that doesn’t work in non-GUI session like a terminal.

You just have to install pinentry for dumb terminal

```bash apt install pinentry-tty </code>

Tell gpg-agent to use another version of pinentry

echo "pinentry-program /usr/bin/pinentry-tty" >> ~/.gnupg/gpg-agent.conf

Restart the agent

gpgconf -K gpg-agent
gpgconf --launch gpg-agent

Set the TTY env var for GPG

export GPG_TTY=$(tty)

Optionnaly, you can make it permanent with

echo "export GPG_TTY=$(tty)" >> ~/.bashrc

Finally you can test your gpg installation with :

echo "test" | gpg --clearsign