Keysign – OpenPGP key signing helper

Keysign is a graphical front end for GnuPG designed to make in-person OpenPGP key signing less cumbersome.

It is intended for two people meeting to verify and certify one another’s identities. Rather than downloading a key from a public keyserver, the application obtains an authenticated copy directly from the other participant. The key can be transferred over the local network or Bluetooth. A QR code carries a message authentication code that confirms the transfer, while the fingerprint can be entered manually when it has been verified through another trusted channel.

After the user checks the identities attached to the received key, Keysign certifies each user ID separately. It encrypts the resulting certifications for their intended recipients and opens the configured email client with a prepared message and attachment. This avoids storing SMTP credentials within the application. The graphical interface uses GTK 4 and Libadwaita.

This is free and open source software.

Key Features

• Lists available private keys and lets the user choose the signing key.
• Discovers nearby participants over the local network using Avahi.
• Offers Bluetooth as an alternative method of transferring keys.
• Scans the other participant’s QR code using a camera.
• Allows manual fingerprint entry when camera scanning is unsuitable.
• Authenticates transferred keys cryptographically without depending on a keyserver.
• Displays the captured QR code to help detect an injected frame.
• Signs every user ID associated with a key separately.
• Encrypts each certification for its intended recipient.
• Opens a prepared message in the user’s configured email client.
• Uses desktop portals or xdg-email instead of built-in SMTP configuration.
• Can save a generated certification to a file.

Website: github.com/GNOME-Keysign/gnome-keysign
Support:
Developer: Tobias Mueller
License: GNU General Public License v3.0

Keysign is written in Python. Learn Python with our recommended free books and free tutorials.

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