Delphi DLL

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 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
success: Boolean;
key: PWideChar;
tweakKey: PWideChar;
dataUnit: PWideChar;
bd: HCkBinData;
crypt: HCkCrypt2;

begin
success := False;

// 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 := CkBinData_Create();
CkBinData_AppendEncoded(bd,'2f3b9dcfbae729583b1d1ffdd16bb6fe2757329435662a78f0','hex');

crypt := CkCrypt2_Create();

CkCrypt2_putCryptAlgorithm(crypt,'aes');
CkCrypt2_putCipherMode(crypt,'xts');
CkCrypt2_putKeyLength(crypt,128);

CkCrypt2_SetEncodedKey(crypt,key,'hex');
CkCrypt2_XtsSetEncodedTweakKey(crypt,tweakKey,'hex');
CkCrypt2_XtsSetEncodedTweakValue(crypt,dataUnit,'hex');

// In-place encrypt the contents of bd.
success := CkCrypt2_EncryptBd(crypt,bd);

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

// Decrypt to revert back to the unencrypted content:
success := CkCrypt2_DecryptBd(crypt,bd);

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

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

CkBinData_Dispose(bd);
CkCrypt2_Dispose(crypt);

end;