(Delphi ActiveX) AES-CMAC

Demonstrates using the AES-CMAC algorithm, which is a keyed hash function similar to HMAC and Poly1305.

Note: Chilkat added AES-CMAC in version 9.5.0.95.

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;
messageBytes: WideString;
bd: TChilkatBinData;
cmac: WideString;
plainText: WideString;
encTag: 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 AES-CMAC
crypt.MacAlgorithm := 'aes-cmac';

// AES-CMAC always uses a 16-byte (128-bit) MAC key.
keyHex := '2b7e151628aed2a6abf7158809cf4f3c';
success := crypt.SetMacKeyEncoded(keyHex,'hex');

// Let's compute the AES-CMAC for the test vector at https://www.rfc-editor.org/rfc/rfc4493#appendix-A
// Here we have 64 bytes in hex representation.
messageBytes := '6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411e5fbc1191a0a52eff69f2445df4f9b17ad2b417be66c3710';

bd := TChilkatBinData.Create(Self);
bd.AppendEncoded(messageBytes,'hex');

// Compute the AES-CMAC for the bytes contained in bd and return the AES-CMAC in hex representation.
crypt.EncodingMode := 'hex_lower';
cmac := crypt.MacBdENC(bd.ControlInterface);
Memo1.Lines.Add(cmac);
// Output should be: 51f0bebf7e3b9d92fc49741779363cfe

// Now do the same for a string:
plainText := '''Twas brillig, and the slithy toves' + #10 + 'Did gyre and gimble in the wabe:' + #10 + 'All mimsy were the borogoves,' + #10 + 'And the mome raths outgrabe.';
encTag := crypt.MacStringENC(plainText);
Memo1.Lines.Add(encTag);

// Output should be: 4fca1fcbd265048d247f99ab57fa3ceb
end;