Currently, packets for allocations, i.e. from relays are parsed inside the `Allocation` struct. We have one of those structs for each relay that `snownet` is talking to. When we disconnect from a relay because it is e.g. not responding, then we deallocate this struct. As a result, message that arrive from this relay can no longer be handled. This can happen when the response time is longer than our timeout. These packets then fall-through and end up being logged as "packet has unknown format". To prevent this, we make the signature on `Allocation` strongly-typed and expect a fully parsed `Message` to be given to us. This allows us to parse the message early and discard it with a DEBUG log in case we don't have the necessary local state to handle it. The functionality here is essentially the same, we just change at what level this is being logged at from WARN to DEBUG. We have to make one additional adjustment to make this work: Guard all messages to be parsed by any `Allocation` to come from port 3478. This is the assigned port that all relays are expected to listen on. If we don't have any local state for a given address, we cannot decide whether it is a STUN message for an agent or a STUN message for a relay that we have disconnected from. Therefore, we need to de-multiplex based on the source port.
Rust development guide
Firezone uses Rust for all data plane components. This directory contains the Linux and Windows clients, and low-level networking implementations related to STUN/TURN.
We target the last stable release of Rust using rust-toolchain.toml.
If you are using rustup, that is automatically handled for you.
Otherwise, ensure you have the latest stable version of Rust installed.
Reading Client logs
The Client logs are written as JSONL for machine-readability.
To make them more human-friendly, pipe them through jq like this:
cd path/to/logs # e.g. `$HOME/.cache/dev.firezone.client/data/logs` on Linux
cat *.log | jq -r '"\(.time) \(.severity) \(.message)"'
Resulting in, e.g.
2024-04-01T18:25:47.237661392Z INFO started log
2024-04-01T18:25:47.238193266Z INFO GIT_VERSION = 1.0.0-pre.11-35-gcc0d43531
2024-04-01T18:25:48.295243016Z INFO No token / actor_name on disk, starting in signed-out state
2024-04-01T18:25:48.295360641Z INFO null
Benchmarking on Linux
The recommended way for benchmarking any of the Rust components is Linux' perf utility.
For example, to attach to a running application, do:
- Ensure the binary you are profiling is compiled with the
releaseprofile. sudo perf record -g --freq 10000 --pid $(pgrep <your-binary>).- Run the speed test or whatever load-inducing task you want to measure.
sudo perf script > profile.perf- Open profiler.firefox.com and load
profile.perf
Instead of attaching to a process with --pid, you can also specify the path to executable directly.
That is useful if you want to capture perf data for a test or a micro-benchmark.