SHA-3 cryptographic hash and SHAKE256 extendable-output functions (XOF). The SHA-3 Secure Hash Standard was published by the National Institute of Standards and Technology (NIST) in 2015 at <doi:10.6028/NIST.FIPS.202>. Fast and memory-efficient implementation using the core algorithm from 'Mbed TLS' under the Trusted Firmware Project <https://www.trustedfirmware.org/projects/mbed-tls/>.
copied from cf-post-staging / r-secretbase