If `FIREZONE_DNS_CONTROL` is set to `systemd-resolved`, then shell out
to `resolvectl` to request all system DNS queries to go to Firezone's
sentinel DNS server(s).
```[tasklist]
- [ ] Figure out how to stop the runner from using the Docker bridge iface
```
---------
Signed-off-by: Reactor Scram <ReactorScram@users.noreply.github.com>
Co-authored-by: Thomas Eizinger <thomas@eizinger.io>
Attempt at cleaning a couple things I missed in code review.
The old httpbin resource wasn't being used anyhow, so I just deduped
them and updated things in a couple other places that had drifted.
Hopefully this fixes the [flaky
CI](https://github.com/firezone/firezone/actions/runs/7918422653/job/21616835910)
Regardless of `FIREZONE_DNS_CONTROL`, always try to notify systemd that
we've started.
I had accidentally conflated the idea of running as a systemd service
with the idea of using systemd to control DNS. They're separate, but
I'll keep the service unit in here and always use `sd-notify` since it
should be harmless to use even in Alpine.
~~If `FIREZONE_DNS_CONTROL` is `systemd-resolved`, try to notify systemd
that we've finished startup and the tunnel is ready.~~
Also adds a CI test, including a systemd service file that is **not**
ready for general use.
Ready for review once it's green.
---------
Signed-off-by: Reactor Scram <ReactorScram@users.noreply.github.com>
Co-authored-by: Thomas Eizinger <thomas@eizinger.io>
Only user-facing if users are using the Docker image for the Linux
client.
I split off a module for `/etc/resolv.conf` since the code and unit
tests are about 300 lines and aren't related to the rest of the
`tun_linux.rs` code.
---------
Signed-off-by: Reactor Scram <ReactorScram@users.noreply.github.com>
This improves maintenance because we can now use a regular matrix for
the integration tests and one can locally use tools like shellcheck or a
`bash-lsp` during development.
---------
Signed-off-by: Jamil <jamilbk@users.noreply.github.com>
Co-authored-by: Jamil <jamilbk@users.noreply.github.com>
