RustCrypto: Modular Crypt Format

Pure Rust implementation of the Modular Crypt Format (MCF), which is used to store password hashes.

About

Modular Crypt Format is the name for a bespoke set of formats that take the form ${id}$..., where {id} is a short numeric or lower case alphanumeric algorithm identifier optionally containing a hyphen character (-), followed by $ as a delimiter, further followed by an algorithm-specific serialization of a password hash, typically using a variant (often an algorithm-specific variant) of Base64.

This algorithm-specific serialization contains one or more fields ${first}[${second}]..., where each field only uses characters in the regexp range [A-Za-z0-9./+=,\-].

Note that MCF has no official specification describing it, and no central registry of identifiers exists, nor are there more specific rules for the format than outlined above. MCF is more of an ad hoc idea of how to serialize password hashes rather than a standard.

This crate provides types for working with Modular Crypt Format in as generic a manner as possible.

For more information and history on MCF, see the PassLib documentation.

Example (SHA-crypt w\ SHA-512):

$6$rounds=100000$exn6tVc2j/MZD8uG$BI1Xh8qQSK9J4m14uwy7abn.ctj/TIAzlaVCto0MQrOFIeTXsc1iwzH16XEWo/a7c7Y9eVJvufVzYAs4EsPOy0

Minimum Supported Rust Version

This crate requires Rust 1.85 at a minimum.

We may change the MSRV in the future, but it will be accompanied by a minor version bump.

License

Licensed under either of:

at your option.

Contribution