Lib.rs

A simple instantiation/configuration of the opaque-ke OPAQUE implementation.

OPAQUE (see the Internet-Draft) is an upcoming standard for password authentication. It is more secure than a traditional simple salt and password hash scheme.

It enables a workflow where the server never learns the user password, yet the server does not need to provide the salt to anyone who asks, providing security against pre-computation attacks.

It uses a basic CipherSuite configured as follows:

• Ristretto255 as the OprfCs, i.e. the voprf CipherSuite, which means using curve25519_dalek as the Ristretto implementation and sha2's Sha512 as the hash implementation
• Ristretto255 as the key exchange group (KeGroup), again implemented using curve25519_dalek
• opaque-ke's own TripleDH as KeyExchange
• argon2 default Argon2 as the key stretching function (Ksf)

It exposes four functions on both the server and client: login finish/start and register finish/start; as well as a key generation function. It also exposes a number of constants for the sizes of various structs.

It is optimized for the usecase in which the server is stateless, but the client stateful.

opaque-borink is useful as a stand-alone library, but also serves as the core library for opaquepy and @tiptenbrink/opaquewasm, bindings for Python and WebAssembly, respectively.

Changelog

v0.4.1

• Adds support for building on newer Rust, backports Argon v0.4.1 support to the fixed version, should still work as before

v0.5.0

• BREAKING: Update OPAQUE to v3, which is a new protocol version and thus previous registrations are no longer valid
• BREAKING: Update Argon2 to v0.5, which uses different default parameters, also causing registrations to become invalid
• It is therefore recommended to reregister and reauthenticate all new users

v0.6.0

• BREAKING: The entire API has been reengineered to be somewhat more flexible and no longer only have base64url input/output