This library implements the SHA suite of message digest functions,
according to NIST FIPS 180-2 (with the SHA-224 addendum), as well as
the SHA-based HMAC routines. The functions have been tested against
most of the NIST and RFC test vectors for the various functions.
While some attention has been paid to performance, these do not
presently reach the speed of well-tuned libraries, like OpenSSL.
