0aab954fa9
ECN information is helpful to allow the congestion controllers to more easily fine-tune their send and receive windows. When a Firezone Client receives an IP packet where the ECN bits signal an ECN capable transport, we mirror this bit on the UDP datagram that carries the encrypted IP packet. When receiving a datagram with ECN bits set, the Gateway will then apply these bits to the decrypted IP packet and pass it along towards its destination. This implementation is unfortunately a bit too naive. Not all devices on the Internet support ECN and therefore, we may receive a datagram that has its ECN bits cleared when the ECN bits on the inner IP packet still signal an ECN capable transport. In this case, we should _not_ override the ECN bits and instead pass the IP packet along as is. Network devices along the path between Gateway and Resource may still use these ECN bits to signal congestion. We fix this by making the `with_ecn` function on `IpPacket` private. It is not meant to be used outside of the module. We supersede it with a `with_ecn_from_transport` function that implements the above logic. --------- Signed-off-by: Thomas Eizinger <thomas@eizinger.io> Co-authored-by: Jamil <jamilbk@users.noreply.github.com>
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.