| # mls-rs   [![Build Status]][actions] [![Latest Version]][crates.io] [![API Documentation]][docs.rs] [](https://codecov.io/gh/awslabs/mls-rs) |
| |
| [build status]: https://img.shields.io/github/checks-status/awslabs/mls-rs/main |
| [actions]: https://github.com/awslabs/mls-rs/actions?query=branch%3Amain++ |
| [latest version]: https://img.shields.io/crates/v/mls-rs.svg |
| [crates.io]: https://crates.io/crates/mls-rs |
| [api documentation]: https://docs.rs/mls-rs/badge.svg |
| [docs.rs]: https://docs.rs/mls-rs |
| |
| <!-- cargo-sync-readme start --> |
| |
| An implementation of the [IETF Messaging Layer Security](https://messaginglayersecurity.rocks) |
| end-to-end encryption (E2EE) protocol. |
| |
| ## What is MLS? |
| |
| MLS is a new IETF end-to-end encryption standard that is designed to |
| provide transport agnostic, asynchronous, and highly performant |
| communication between a group of clients. |
| |
| ## MLS Protocol Features |
| |
| - Multi-party E2EE [group evolution](https://www.rfc-editor.org/rfc/rfc9420.html#name-cryptographic-state-and-evo) |
| via a propose-then-commit mechanism. |
| - Asynchronous by design with pre-computed [key packages](https://www.rfc-editor.org/rfc/rfc9420.html#name-key-packages), |
| allowing members to be added to a group while offline. |
| - Customizable credential system with built in support for X.509 certificates. |
| - [Extension system](https://www.rfc-editor.org/rfc/rfc9420.html#name-extensions) |
| allowing for application specific data to be negotiated via the protocol. |
| - Strong forward secrecy and post compromise security. |
| - Crypto agility via support for multiple [cipher suites](https://www.rfc-editor.org/rfc/rfc9420.html#name-cipher-suites). |
| - Pre-shared key support. |
| - Subgroup branching. |
| - Group reinitialization for breaking changes such as protocol upgrades. |
| |
| ## Features |
| |
| - Easy to use client interface that can manage multiple MLS identities and groups. |
| - 100% RFC 9420 conformance with support for all default credential, proposal, |
| and extension types. |
| - Support for WASM builds. |
| - Configurable storage for key packages, secrets and group state |
| via traits along with provided "in memory" and SQLite implementations. |
| - Support for custom user proposal and extension types. |
| - Ability to create user defined credentials with custom validation |
| routines that can bridge to existing credential schemes. |
| - OpenSSL and Rust Crypto based cipher suite implementations. |
| - Crypto agility with support for user defined cipher suite. |
| - Extensive test suite including security and interop focused tests against |
| pre-computed test vectors. |
| |
| ## Crypto Providers |
| |
| For cipher suite descriptions see the RFC documentation [here](https://www.rfc-editor.org/rfc/rfc9420.html#name-mls-cipher-suites) |
| |
| | Name | Cipher Suites | X509 Support | |
| | ----------- | ------------- | --------------- | |
| | OpenSSL | 1-7 | Stable | |
| | AWS-LC | 1,2,3,5,7 | Stable | |
| | Rust Crypto | 1,2,3 | ⚠️ Experimental | |
| | Web Crypto | ⚠️ Experimental 2,5,7 | Unsupported | |
| |
| ## Security Notice |
| |
| This library has been validated for conformance to the RFC 9420 specification but has not yet received a full security audit by a 3rd party. |
| |
| <!-- cargo-sync-readme end --> |
| |
| ## License |
| |
| This library is licensed under the Apache-2.0 or the MIT License. |
