Delphi ActiveX

AES XTS Mode

See more Encryption Examples

Demonstrates the AES-XTS mode of operation.

Note: This example requires Chilkat v9.5.0.91 or greater.

Delphi ActiveX

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
success: Integer;
key: WideString;
tweakKey: WideString;
dataUnit: WideString;
bd: TChilkatBinData;
crypt: TChilkatCrypt2;

begin
success := 0;

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

// Here we have a sample from CAVS validatition data:

// COUNT = 301
// DataUnitLen = 200
// Key = 
// 394c97881abd989d29c703e48a72b397
// a7acf51b59649eeea9b33274d8541df4
// i = 4b15c684a152d485fe9937d39b168c29
// PT = 2f3b9dcfbae729583b1d1ffdd16bb6fe2757329435662a78f0
// CT = f3473802e38a3ffef4d4fb8e6aa266ebde553a64528a06463e

// Note: The above sample requires an AES-XTS implementation that fully supports ciphertext-stealing
// because the data to be encrypted is not an even multiple of the AES block size (i.e. not a multiple of 16 bytes).
// Chilkat fully supports AES-XTS with ciphertext stealing.
// (i.e. Chilkat implements XEX-based tweaked-codebook mode with ciphertext stealing (XTS))

key := '394c97881abd989d29c703e48a72b397';
tweakKey := 'a7acf51b59649eeea9b33274d8541df4';
dataUnit := '4b15c684a152d485fe9937d39b168c29';

bd := TChilkatBinData.Create(Self);
bd.AppendEncoded('2f3b9dcfbae729583b1d1ffdd16bb6fe2757329435662a78f0','hex');

crypt := TChilkatCrypt2.Create(Self);

crypt.CryptAlgorithm := 'aes';
crypt.CipherMode := 'xts';
crypt.KeyLength := 128;

crypt.SetEncodedKey(key,'hex');
crypt.XtsSetEncodedTweakKey(tweakKey,'hex');
crypt.XtsSetEncodedTweakValue(dataUnit,'hex');

// In-place encrypt the contents of bd.
success := crypt.EncryptBd(bd.ControlInterface);

Memo1.Lines.Add('CT = ' + bd.GetEncoded('hexlower'));

// Decrypt to revert back to the unencrypted content:
success := crypt.DecryptBd(bd.ControlInterface);

Memo1.Lines.Add('PT = ' + bd.GetEncoded('hexlower'));

// Output:
// CT = f3473802e38a3ffef4d4fb8e6aa266ebde553a64528a06463e
// PT = 2f3b9dcfbae729583b1d1ffdd16bb6fe2757329435662a78f0
end;