Files
firezone/rust/gateway
Thomas Eizinger fa790b231a fix(gateway): respond with SERVFAIL for missing nameserver (#9061)
When we implemented #8350, we chose an error handling strategy that
would shutdown the Gateway in case we didn't have a nameserver selected
for handling those SRV and TXT queries. At the time, this was deemed to
be sufficiently rare to be an adequate strategy. We have since learned
that this can indeed happen when the Gateway starts without network
connectivity which is quite common when using tools such as terraform to
provision infrastructure.

In #9060, we fix this by re-evaluating the fastest nameserver on a
timer. This however doesn't change the error handling strategy when we
don't have a working nameserver at all. It is practically impossible to
have a working Gateway yet us being unable to select a nameserver. We
read them from `/etc/resolv.conf` which is what `libc` uses to also
resolve the domain we connect to for the WebSocket. A working WebSocket
connection is required for us to establish connections to Clients, which
in turn is a precursor to us receiving DNS queries from a Client.

It causes unnecessary complexity to have a code path that can
potentially terminate the Gateway, yet is practically unreachable. To
fix this situation, we remove this code path and instead reply with a
DNS SERVFAIL error.

---------

Signed-off-by: Thomas Eizinger <thomas@eizinger.io>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
2025-05-09 05:55:48 +00:00
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gateway

This crate houses the Firezone gateway.

Building

You can build the gateway using: cargo build --release --bin firezone-gateway

You should then find a binary in target/release/firezone-gateway.

Running

The Firezone Gateway supports Linux only. To run the Gateway binary on your Linux host:

  1. Generate a new Gateway token from the "Gateways" section of the admin portal and save it in your secrets manager.
  2. Ensure the FIREZONE_TOKEN=<gateway_token> environment variable is set securely in your Gateway's shell environment. The Gateway requires this variable at startup.
  3. Set FIREZONE_ID to a unique string to identify this gateway in the portal, e.g. export FIREZONE_ID=$(uuidgen). The Gateway requires this variable at startup.
  4. Now, you can start the Gateway with:
firezone-gateway

If you're running as a non-root user, you'll need the CAP_NET_ADMIN capability to open /dev/net/tun. You can add this to the gateway binary with:

sudo setcap 'cap_net_admin+eip' /path/to/firezone-gateway

Ports

The gateway requires no open ports. Connections automatically traverse NAT with STUN/TURN via the relay.