7adbf9c6af
As the final step in removing `pnet_packet`, we need to introduce `-Mut` equivalent slices for UDP, TCP and ICMP packets. As a starting point, introducing `UpdHeaderSliceMut` and `TcpHeaderSliceMut` is fairly trivial. The ICMP variants are a bit trickier because those are different for IPv4 and IPv6. Additionally, ICMP for IPv4 is quite complex because it can have a variable header length. Additionally. for both variants, the values in byte range 5-8 are semantically different depending on the ICMP code. This requires us to design an API that balances ergonomics and correctness. Technically, an ICMP identifier and sequence can only be set if the ICMP code is "echo request" or "echo reply". However, adding an additional parsing step to guarantee this in the type system is quite verbose. The trade-off implemented in this PR allows to us to directly write to the byte 5-8 using the `set_identifier` and `set_sequence` functions. To catch errors early, this functions have debug-assertions built in that ensure that the packet is indeed an ICMP echo packet. Resolves: #6366.
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
benchprofile. sudo perf 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.