SHA256, SHA384 and SHA512 + HMAC:
Many developers need these functions, while working with
different kinds of external APIs, like Bitcoin and altcoin exchanges
where it is often necessary to send data with the confirmation of
parameters validity through HMAC-SHA512, HMAC-SHA384 and HMAC-SHA256.
The MQL5 version of SHA512 library can be found here: https://www.mql5.com/en/code/18158. Besides SHA512, added SHA256 and SHA384 support in form of separate libraries.
HMAC functions were ported from https://en.wikipedia.org/wiki/Hash-based_message_authentication_code
Use example (tested on http://www.freeformatter.com/hmac-generator.html)
input string phrase = "The quick brown fox jumps over the lazy dog";
input string phrase_key = "ABCDEFG";
Author: Grzegorz Korycki