# Functions
CounterMode implements the counter mode KDF that uses a psuedo-random-function (PRF) along with a counter to generate derived keys.
HMACSHA256PRF is a pseudo-random-function (PRF) that uses an HMAC-SHA256.
# Constants
HMACSHA256PRFLen is the length of output from HMACSHA256PRF.
# Type aliases
PRF is a pseudo-random function that takes a key or seed, as well as additional binary data and generates output that is indistinguishable from random.