All of our Linux applications have a soft-dependency on systemd. That is, in the default configuration, we expect systemd to be present on the machine. The only exception here are the docker containers for Headless Client and Gateway. For the GUI client in particular, systemd is a hard-dependency in order to control DNS on the system which we do via `systemd-resolved`. To secure the communication between the GUI client and its tunnel process, we automatically create a group called `firezone-client` to which the user gets added. All members of the group are allowed to access the unix socket which is used for IPC between the two processes. Membership in this group is also a prerequisite for accessing any of the configuration files. On the first launch of the GUI client on a Linux system, this presents a problem. For group membership changes to take the effect, the user needs to reboot. We say that in the documentation but it is unclear whether all users will read that thoroughly enough. To help the user, the GUI client checks for membership of the current user in the group and alerts the user via a dialog box if that isn't the case. This would all be fine if it would actually work. Unfortunately, that check ends up being too late in the process. If we aren't a member of the group, we cannot read the device ID and bail early, thus never reaching the check and terminating the process without any dialog box or user-visible error. We could attempt to fix this by shuffling around some of the startup init code. That is a sub-optimal solution however because it a) may get broken again in the future and b) it means we have to delay initialisation of telemetry until a much later point. Given that this is only a problem on Linux, a better solution is to simply not rely on the disk-based device ID at all. Instead, we can integrate with systemd and deterministically derive a device ID from the unique machine ID and a randomly chosen "app ID". For backwards-compatibility reasons, the disk-based device ID is still prioritised. For all new installs however, we will use the one based on `/etc/machine-id`.
gui-client
This crate houses a GUI client for Linux and Windows.
Setup (Ubuntu)
To compile natively for x86_64 Linux:
- Install rustup
- Install pnpm
sudo apt-get install build-essential curl file libayatana-appindicator3-dev librsvg2-dev libssl-dev libwebkit2gtk-4.1-dev libxdo-dev wget
Setup (Windows)
To compile natively for x86_64 Windows:
- Install rustup
- Install pnpm
Recommended IDE Setup
(From Tauri's default README)
Building
Builds are best started from the frontend tool pnpm. This ensures typescript
and css is compiled properly before bundling the application.
See the package.json script for more details as to what's
going on under the hood.
# Builds a release exe
pnpm build
# Linux:
# The release exe and deb package are up in the workspace.
stat ../target/release/firezone
stat ../target/release/bundle/deb/*.deb
# Windows:
# The release exe and MSI installer should be up in the workspace.
# The exe can run without being installed
stat ../target/release/Firezone.exe
stat ../target/release/bundle/msi/Firezone_0.0.0_x64_en-US.msi
Signing the Windows MSI in GitHub CI
The MSI is signed in GitHub CI using the firezone/firezone repository's
secrets. This was originally set up using these guides for inspiration:
- https://melatonin.dev/blog/how-to-code-sign-windows-installers-with-an-ev-cert-on-github-actions/
- https://support.globalsign.com/code-signing/code-signing-using-azure-key-vault
Renewing / issuing a new code signing certificate and associated Azure entities is outside the scope of this section. Use the guides above if this needs to be done.
Instead, you'll most likely simply need to rotate the Azure CodeSigning Application's client secret.
To do so, login to the Azure portal using your @firezoneprod.onmicrosoft.com account.
Try to access it via the following deep-link.
If that doesn't work:
- Go to the
Microsoft Entra IDservice - Click on
App Registrations - Make sure the tab
All applicationsis selected - Find and navigate to the
CodeSigningapp registration - Client on
client credentials - Click
New client secret - Note down the secret value. This should be entered into the GitHub repository's secrets as
AZURE_CLIENT_SECRET.
Running
From this dir:
# This will start the frontend tools in watch mode and then run `tauri dev`
pnpm dev
# You can call debug subcommands on the exe from this directory too
# e.g. this is equivalent to `cargo run -- debug hostname`
cargo tauri dev -- -- debug hostname
# The exe is up in the workspace
stat ../target/debug/Firezone.exe
The app's config and logs will be stored at
C:\Users\$USER\AppData\Local\dev.firezone.client.
Platform support
Ubuntu 22.04 and newer is supported.
Tauri says it should work on Windows 10, Version 1803 and up. Older versions may work if you manually install WebView2
x86_64 architecture is supported for Windows. aarch64 and x86_64 are supported for Linux.
Threat model
See Security