01e16e87d6
Building on top of a series of refactors and smaller features, this PR enables connlib to send DNS queries over HTTPS to one or more configured DoH providers. A DoH server itself is addressed via a domain which first needs to be resolved before it can be contacted. The RFC recommends to perform this bootstrapping using the system DNS resolvers. For connlib, this is a bit tricky because the system resolvers may already be set to connlib's sentinel servers by the time we need to bootstrap the DoH clients. Therefore, we maintain a dedicated UDP DNS client inside connlib's `Io` component which is always configured with the latest system DNS resolvers known to connlib. The actual bootstrapping of a DoH client happens in the following cases: 1. Our TUN device configuration changes and the configured DNS servers mapping contains DoH upstreams. 2. We need to make a DNS query to a DoH server but don't have a client yet. The first case ensures we bootstrap the DoH clients as early as possible. The latter case ensures we have a self-healing behaviour in case the TCP connection to the DoH server breaks (in which case the DoH client will be de-allocated). Once the DoH client is initialized, making queries with it is a trivial act of sending an HTTP request and parsing the HTTP response. Within connlib, this now requires almost no special handling apart from a new `dns::Upstream` type that differentiates between Do53 servers (addressed by a `SocketAddr`) and DoH servers (addressed by a `Url`). Related: #10764 Related: #10788 Related: #10850 Related: #10851 Related: #10856 Related: #10857 Related: #10871 Related: #10872 Related: #10875 Related: #10881 Resolves: #10790
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.