ed2bc0bd25
Even prior to #10373, failures in resolving a name on the Gateway for a DNS resource resulted in a failure of setting up the DNS resource NAT. Without the DNS resource NAT, packets for that resource bounced on the Gateway because we didn't have any traffic filters. A non-existent filter is being treated as a "traffic not allowed" error and we respond with an ICMP permission denied error. For domains where both the A and AAAA query result in NXDOMAIN, that isn't necessarily appropriate. Instead, I am proposing that for such cases, we want to return a regular "address/host unreachable" ICMP error instead of the more specific "permission denied" variant. To achieve that, we refactor the Gateway's peer state to be able to hold an `Option<IpAddr>` inside the `TranslationState`. This allows us to always insert an entry for each proxy IP, even if we did not resolve any IPs for it. Then, when receiving traffic for a proxy IP where the resolved IP is `None`, we reply with the appropriate ICMP error. As part of this, we also simplify the assignment of the proxy IPs. With the NAT64 module removed, there is no more reason to cross-assign IPv4 and IPv6 addresses. We can simply leave the mappings for e.g. IPv6 proxy addresses empty if the AAAA query didn't resolve anything. From the Client's perspective, not much changes. The DNS resource NAT setup will now succeed, even for domains that don't resolve to anything. This doesn't change any behaviour though as we are currently already passing packets through for failed DNS resource NAT setups. The main change is that we now send back a different ICMP error. Most importantly, the "address/host unreachable variant" does not trigger #10462.
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.