ghc-cryptohash-sha256
Fast, pure and practical SHA-256 implementation
A practical incremental and one-pass, pure API to the [SHA-256 cryptographic hash algorithm](https://en.wikipedia.org/wiki/SHA-2) according to [FIPS 180-4](http://dx.doi.org/10.6028/NIST.FIPS.180-4) with performance close to the fastest implementations available in other languages. The core SHA-256 algorithm is implemented in C and is thus expected to be as fast as the standard [sha256sum(1) tool](https://linux.die.net/man/1/sha256sum); for instance, on an /Intel Core i7-3770/ at 3.40GHz this implementation can compute a SHA-256 hash over 230 MiB of data in under one second. (If, instead, you require a pure Haskell implementation and performance is secondary, please refer to the [SHA package](https://hackage.haskell.org/package/SHA).) Additionally, this package provides support for - HMAC-SHA-256: SHA-256-based [Hashed Message Authentication Codes](https://en.wikipedia.org/wiki/HMAC) (HMAC) - HKDF-SHA-256: [HMAC-SHA-256-based Key Derivation Function](https://en.wikipedia.org/wiki/HKDF) (HKDF) conforming to [RFC6234](https://tools.ietf.org/html/rfc6234), [RFC4231](https://tools.ietf.org/html/rfc4231), [RFC5869](https://tools.ietf.org/html/rfc5869), et al.. === Relationship to the 'cryptohash' package and its API This package has been originally a fork of 'cryptohash-0.11.7' because the 'cryptohash' package had been deprecated and so this package continues to satisfy the need for a lightweight package providing the SHA-256 hash algorithm without any dependencies on packages other than 'base' and 'bytestring'. The API exposed by 'cryptohash-sha256-0.11.*''s "Crypto.Hash.SHA256" module is guaranteed to remain a compatible superset of the API provided by the 'cryptohash-0.11.7''s module of the same name. Consequently, this package is designed to be used as a drop-in replacement for 'cryptohash-0.11.7''s "Crypto.Hash.SHA256" module, though with a [clearly smaller footprint by almost 3 orders of magnitude](https://www.reddit.com/r/haskell/comments/5lxv75/psa_please_use_unique_module_names_when_uploading/dbzegx3/).
BSD-3-Clause