View Source ExSha3 (ex_sha3 v0.1.4)
ExSha3 supports the three hash algorithms:
* KECCAK1600-f the original pre-fips version as used in Ethereum
* SHA3 the fips-202 approved final hash
* SHAKE
Keccak and SHA3 produce fixed length strings corresponding to their bit length, while shake produces an arbitary length output according to the provided outlen parameter.