A practical incremental and one-pass, pure API to the SHA-256 cryptographic
hash algorithm according to 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; 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
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
conforming to RFC6234,
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