WolfSSL (Rust)

This repository attempts to build safe and idiomatic abstractions for the WolfSSL Embedded SSL/TLS Library (C).

There are two parts to this:

• The wolfssl-sys crate auto-generates unsafe Rust bindings through bindgen, to C functions provided by the WolfSSL library.
• The wolfssl crate then build safe and idiomatic abstractions on top of the unsafe layer.

Why WolfSSL?

At ExpressVPN we love WolfSSL. It's fast, secure, easy to use and of course it's Open Source. That's why when we were looking at TLS libraries to use as the core of Lightway, WolfSSL was a clear winner. Now that we're doing more research with Rust, it's only natural that we'd want to keep using WolfSSL, but alas, there weren't any Rust bindings available.

So we built one :)

Building and Running

After cloning this repo, you'll also need to clone the submodules for the WolfSSL source code via:

git submodule update --init

Currently, the usual commands from cargo works perfectly fine. Common commands include the following:

cargo build

cargo test

cargo clippy

Building with Earthly

There is also an Earthfile provided. For example, here's how you can build the crate in Earthly:

earthly +build-crate

For more information about the different Earthly targets available, run:

earthly doc

Speeding up development with Earthly Satellites

Please refer to official documentation for Earthly Satellites.

If you are a member of ExpressVPN, you can get access to the same Earthly organization used in our CI. The organization is named expressvpn, inside which contains a satellite named wolfssl-rs.

If you are not a member of ExpressVPN, you may set up your own Earthly satellite according the official instructions above.

Releasing

This repository is a monorepo for two crates: wolfssl-sys and wolfssl. They should always be released together. Since wolfssl depends on wolfssl-sys, they should be released in the below order:

1. Bump the crate version wolfssl-sys, update the version specified under dependencies in the wolfssl crate, and release it (Follow the section Releasing a Single Crate)
2. Bump the crate version wolfssl and release it (same procedure as above)

Releasing a Single Crate

A GitHub Workflow is set up to automate the release of crates in this repo. Upon a release, it will create a release in GitHub and Crates.io

To create a new release, follow the below steps:

1. Bump the version in <crate-name>/Cargo.toml. We follow the semantic versioning pattern when deciding a new version number
2. Open a PR, attach the release label to the PR
3. Observe that a comment is add to the PR, indicating the current version and the upcoming version
4. Merge the PR, a new version should be released to both GitHub and Crates.io