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omemogajimplugin

Last edited by Philipp Hörist

OMEMO Plugin for Gajim

This plugin has been integrated into Gajim's core since Gajim 1.8.0. It is no longer necessary to install this plugin!

Please refer to Gajim's wiki for help.

This plugin adds support for the OMEMO Encryption to Gajim. The OMEMO Plugin is free software distributed under the GNU General Public License version 3 or any later version.

Installation

Windows

OMEMO is automatically installed on Windows.

MacOS

pip3 install --upgrade cryptography python-axolotl qrcode

afterwards download the plugin via Gajims Plugin Manager.

Linux

Debian & Ubuntu

The package gajim-omemo is available in backports, testing, and universe repos.

Use sudo apt-get install gajim-omemo to install the plugin.

Fedora

OMEMO is automatically installed on Fedora Linux. (Tested on Fedora 37)

python3-qrcode needs to be installed manually to get QR codes for fingerprints.

Gentoo

Use layman -a flow && emerge gajim-omemo to install the plugin.

Distributions without a package

Install the plugin with Gajims Plugin Manager. You need Gajim 1.3.0 or higher. If your package manager does not provide an up to date version you can visit gajim.org for further install instructions.

  1. Check if you have Gajim 1.3.0 or higher installed
  2. sudo apt-get install build-essential libssl-dev libffi-dev python3-dev
  3. sudo apt-get install python3-setuptools
  4. sudo apt-get install python3-cryptography
  5. sudo apt-get install python3-axolotl
  6. Restart Gajim, and activate OMEMO in Gajims Plugin Manager

Running

Enable the OMEMO plugin in the Plugin Manager. If your contact supports OMEMO, you should be able to activate it using the lock icon in the lower right of your chat window.

When you send your first message, the plugin will query your contacts encryption keys and you will see them in a readable fingerprint format in the fingerprint window which pops up. You have to trust at least one fingerprint to be able to send messages. You can receive messages from fingerprints where you didn't make a trust decision, but you can't receive Messages from not trusted fingerprints.

Verification QR Codes

It is possible to show a QR Code for verification in the plugin's configuration window.

You have to install the python3-qrcode packages for QR Codes to work (Debian, Ubuntu).

If you want to use PIP for installing python packages, qrcode and pillow packages have to be installed.

What is Blind Trust Before Verification

The concept of Blind Trust Before Verification (BTBV) in short: Automatically trust all new devices of contacts that haven’t been verified before, and prompt for manual confirmation each time a verified contact adds a new device.

Groupchat

Groupchat with OMEMO encryption works only in rooms that are:

  • non-anonymous
  • members-only

File transfer

If your server supports HTTP File Upload (See ServerInfo Window) your file transfers are encrypted. P2P file transfers via Jingle are not encrypted.

Debugging

To see OMEMO related debug output, start Gajim with the following parameters:

-l gajim.plugin_system.omemo=DEBUG

I found a bug

Please report it to the issue tracker. If you are experiencing misbehaviour, please provide detailed steps to reproduce this and provide debugging output. Also, please always mention the exact Gajim version you are using.

Contact

You can contact us at gajim@conference.gajim.org.