# l4p > Hey, now we are on level 4! ![CI](https://drone-ci.kiers.eu/api/badges/jjkiers/layer4-proxy/status.svg) `l4p` is a layer 4 proxy implemented by Rust to listen on specific ports and transfer TCP data to remote addresses (only TCP) according to the configuration. ## Features - Listen on specific port and proxy to local or remote port - SNI-based rule without terminating TLS connection - DNS-based backend with periodic resolution ## Installation To gain best performance on your computer's architecture, please consider build the source code. First, you may need [Rust tool chain](https://rustup.rs/). ```bash $ cd l4p $ cargo build --release ``` Binary file will be generated at `target/release/l4p`, or you can use `cargo install --path .` to install. Or you can use Cargo to install `l4p`: ```bash $ cargo install l4p ``` Or you can download binary file form the Release page. ## Configuration `l4p` will read yaml format configuration file from `/etc/l4p/l4p.yaml`, and you can set custom path to environment variable `L4P_CONFIG`, here is an minimal viable example: ```yaml version: 1 log: info servers: proxy_server: listen: - "127.0.0.1:8081" default: remote upstream: remote: "tcp://www.remote.example.com:8082" # proxy to remote address ``` There are two upstreams built in: * Ban, which terminates the connection immediately * Echo, which reflects back with the input For detailed configuration, check [this example](./config.yaml.example). ## Thanks - [`fourth`](https://crates.io/crates/fourth), of which this is a heavily modified fork. ## License `l4p` is available under terms of Apache-2.0.