BoringTun, a Userspace WireGuard Implementation in Rust

It is called BoringTun, and is a userspace implementation of the WireGuard® protocol written in Rust. WireGuard is relatively new project that attempts to replace old VPN protocols, with a simple, fast, and safe protocol. Unlike legacy VPNs, WireGuard is built around the Noise Protocol Framework and relies only on a select few, modern, cryptographic primitives: X25519 for public key operations, ChaCha20-Poly1305 for authenticated encryption, and Blake2s for message authentication.

Source: blog.cloudflare.com