(Delphi DLL) HMAC Hex String

Demonstrates how to compute an HMAC using a hexidecimal key and data.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, BinData, Crypt2;

...

procedure TForm1.Button1Click(Sender: TObject);
var
crypt: HCkCrypt2;
success: Boolean;
keyHex: PWideChar;
dataHex: PWideChar;
bd: HCkBinData;
macHex: PWideChar;

begin
crypt := CkCrypt2_Create();

success := CkCrypt2_UnlockComponent(crypt,'Anything for 30-day trial');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCrypt2__lastErrorText(crypt));
    Exit;
  end;

//  Set the MAC algorithm to HMAC
CkCrypt2_putMacAlgorithm(crypt,'hmac');

//  Our HMAC key will be the bytes represented in the following hex string.
//  In other words, the HMAC key is composed of the bytes 0x41, 0xC2, 0x1C, ...
//  (It is not composed of the us-ascii string '4', '1', 'C', ...)
keyHex := '41C21CB9D7A02FC5D4FADB9E4755B9DE';
success := CkCrypt2_SetMacKeyEncoded(crypt,keyHex,'hex');

//  Our desire is to HMAC the bytes represented in the following string:
dataHex := 'C22078065B01460001000000010062043BF5B18228C8E02D17BCFE4E00561FA6DEC216EA97195CEB579942E275C21932258E3CD391E507FF4E7FD4C787A8447DA111C54A9C1795E7FF4C0BAA2EDA';

//  We'll need to decode the hex to binary:
bd := CkBinData_Create();
CkBinData_AppendEncoded(bd,dataHex,'hex');

//  Do the HMAC-SHA256 hash and return as a hex string:
CkCrypt2_putEncodingMode(crypt,'hex');
CkCrypt2_putHashAlgorithm(crypt,'sha-256');
macHex := CkCrypt2__macBdENC(crypt,bd);
Memo1.Lines.Add(macHex);

CkCrypt2_Dispose(crypt);
CkBinData_Dispose(bd);

end;