Use DCPcrypt lib from https://sourceforge.net/p/dcpcrypt/code/HEAD/tree/
I took code from: http://keit.co/p/dcpcrypt-hmac-rfc2104/
The code:
uses DCPcrypt2, DCPsha1, DCPblockciphers, DCPrijndael;
function RPad(x: ansistring; c: AnsiChar; s: Integer): ansistring; var i: Integer;
begin...