Hash-based Message Authentication Codes
[https://en.wikipedia.org/wiki/HMAC]
In cryptography, an HMAC (sometimes expanded as either keyed-hash message authentication code or hash-based message authentication code) is a specific type of message authentication code (MAC) involving a cryptographic hash function and a secret cryptographic key. As with any MAC, it may be used to simultaneously verify both the data integrity and authenticity of a message.
select crypto_auth_hmacsha512_keygen() hmac512key \gset
select crypto_auth_hmacsha512('food', :'hmac512key') hmac512 \gset
select is(crypto_auth_hmacsha512_verify(:'hmac512', 'food', :'hmac512key'), true, 'hmac512 verified');
select is(crypto_auth_hmacsha512_verify(:'hmac512', 'fo0d', :'hmac512key'), false, 'hmac512 not verified');