(Delphi ActiveX) HMAC Hex String

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

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

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
crypt: TChilkatCrypt2;
keyHex: WideString;
success: Integer;
dataHex: WideString;
bd: TChilkatBinData;
macHex: WideString;

begin
// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

crypt := TChilkatCrypt2.Create(Self);

// Set the MAC algorithm to HMAC
crypt.MacAlgorithm := '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 := crypt.SetMacKeyEncoded(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 := TChilkatBinData.Create(Self);
bd.AppendEncoded(dataHex,'hex');

// Do the HMAC-SHA256 hash and return as a hex string:
crypt.EncodingMode := 'hex';
crypt.HashAlgorithm := 'sha-256';
macHex := crypt.MacBdENC(bd.ControlInterface);
Memo1.Lines.Add(macHex);
end;