[![github]](https://github.com/rusty-bolt/conntrack-rs)
[![crates-io]](https://crates.io/crates/conntrack)
[![rust-docs]](https://docs.rs/conntrack/)
[![Dependency Status](https://deps.rs/repo/github/rusty-bolt/conntrack-rs/status.svg)](https://deps.rs/repo/github/rusty-bolt/conntrack-rs)

[github]: https://img.shields.io/badge/github-rusty--bolt/conntrack--rs-blueviolet?style=for-the-badge&labelColor=555555&logo=github
[rust-docs]: https://img.shields.io/docsrs/conntrack/latest?style=for-the-badge&logo=rust&color=informational
[crates-io]: https://img.shields.io/crates/v/conntrack.svg?style=for-the-badge&logo=rust

---
# conntrack-rs
An API providing access to the Conntrack subsystem of the Linux kernel written in rust 🦀

This library provides access to the [`conntrack`](https://conntrack-tools.netfilter.org/conntrack.html) 
subsystem in the linux kernel leveraging netlink support via the [`neli`](https://docs.rs/neli/latest/neli/index.html) 
library. 

The current version only supplies `Dump()` functionality for the `Conntrack` table. Leveraging the 
[`conntrack-tools`](https://conntrack-tools.netfilter.org/) utility in linux, the `Dump()` behavior 
is equivalent to: `conntrack -L`. Most of the model and attribute parsing supported in this library 
extends beyond the `dump()` command, which allows this library to eventually cover the full feature set
of the conntrack subsystem. 

You can enable byte and packet counters using `sysctl -w net.netfilter.nf_conntrack_acct=1`

# Privileges

You need the `CAP_NET_ADMIN` capability in order to allow your application to receive events from and to send commands to kernel-space, 
excepting the conntrack table dumping operation.

### WSL2 Conntrack

Note that in order to enable connection tracking via `conntrack` on WSL2, you'll need to add the following iptable entry:
```bash
iptables -A INPUT -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
```

# Example

```rust
use conntrack::*;

fn main() -> Result<()> {
    // Create the Conntrack table via netfilter socket syscall
    let mut ct = Conntrack::connect()?;

    // Dump conntrack table as a Vec<Flow>
    let flows = ct.dump()?;

    for flow in flows {
        log::info!("{flow:?}");
    }

    Ok(())
}
```