(Delphi DLL) Example for both AES-128 and ChaCha20 to Encrypt Binary Data

Demonstrates the use of the new EncryptBd and DecryptBd methods introduced in Chilkat v9.5.0.67 to encrypt/decrypt binary bytes.

Note: This example requires Chilkat v9.5.0.67 or greater.

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
jpgBytes: HCkBinData;
success: Boolean;
crypt: HCkCrypt2;
ivHex: PWideChar;
keyHex: PWideChar;

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

// Load a small JPG file to be encrypted/decrypted.
jpgBytes := CkBinData_Create();
success := CkBinData_LoadFile(jpgBytes,'qa_data/jpg/starfish.jpg');
if (success <> True) then
  begin
    Memo1.Lines.Add('Failed to load JPG file.');
    Exit;
  end;

// Show the unencrypted JPG bytes in Base64 format.
// (The "base64_mime" encoding was added in Chilkat v9.5.0.67.
// The "base64" encoding emits a single line of base64, whereas
// "base64_mime" will emit multi-line base64 as it would appear
// in MIME.)
Memo1.Lines.Add(CkBinData__getEncoded(jpgBytes,'base64_mime'));

// Sample base64_mime JPG data:

// 	/9j/4AAQSkZJRgABAgEASABIAAD/7Q18UGhvdG9zaG9wIDMuMAA4QklNA+0AAAAAABAASAAAAAEA
// 	AQBIAAAAAQABOEJJTQPzAAAAAAAIAAAAAAAAAAE4QklNBAoAAAAAAAEAADhCSU0nEAAAAAAACgAB
// 	AAAAAAAAAAI4QklNA/UAAAAAAEgAL2ZmAAEAbGZmAAYAAAAAAAEAL2ZmAAEAoZmaAAYAAAAAAAEA
// 	MgAAAAEAWgAAAAYAAAAAAAEANQAAAAEALQAAAAYAAAAAAAE4QklNBBQAAAAAAAQAAAABOEJJTQQM
// 	...

crypt := CkCrypt2_Create();

// Specify the encryption to be used.
// First we'll do AES-128 CBC
CkCrypt2_putCryptAlgorithm(crypt,'aes');
CkCrypt2_putCipherMode(crypt,'cbc');
CkCrypt2_putKeyLength(crypt,128);

ivHex := '000102030405060708090A0B0C0D0E0F';
CkCrypt2_SetEncodedIV(crypt,ivHex,'hex');

keyHex := '000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F';
CkCrypt2_SetEncodedKey(crypt,keyHex,'hex');

// Do the in-place 128-bit AES CBC encryption.
// The contents of jpgBytes are replaced with the encrypted bytes.
success := CkCrypt2_EncryptBd(crypt,jpgBytes);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCrypt2__lastErrorText(crypt));
    Exit;
  end;

// Examine the JPG bytes again.  The bytes should be different because they are encrypted:
Memo1.Lines.Add(CkBinData__getEncoded(jpgBytes,'base64_mime'));

// Sample base64_mime encrypted JPG data:

// 	sbz0babt1WCkQf5xKMdg/baZAcUBO5GVUUDF2BjVqmd+HrqKN+t6hAcqakL/bdo0q9hYmow0Tp1e
// 	AQ9V9DOiifQUZqWVkR+kL/c45bq8JGFDvgNl0djPt+yYhV789IB/fPH0upx+/ad++WNOlv1IxGMr
// 	Y1x1oERU/IsiEzafUJdI4kZ6FQo2IPGMF/Rm1h79I7hP1yYUFxvJyz+PzaySAUH1nLsNHyDVY5VY
// 	O90aH3steRSYbz8C8UF9wQ3qqEIXQNnnixvoNDnmHyY39VoVBI5F6rnPwYDfAk2t8tmuryFqvwAu
// 	...

// Decrypt to restore back to the original:
success := CkCrypt2_DecryptBd(crypt,jpgBytes);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCrypt2__lastErrorText(crypt));
    Exit;
  end;

Memo1.Lines.Add(CkBinData__getEncoded(jpgBytes,'base64_mime'));

// 	/9j/4AAQSkZJRgABAgEASABIAAD/7Q18UGhvdG9zaG9wIDMuMAA4QklNA+0AAAAAABAASAAAAAEA
// 	AQBIAAAAAQABOEJJTQPzAAAAAAAIAAAAAAAAAAE4QklNBAoAAAAAAAEAADhCSU0nEAAAAAAACgAB
// 	AAAAAAAAAAI4QklNA/UAAAAAAEgAL2ZmAAEAbGZmAAYAAAAAAAEAL2ZmAAEAoZmaAAYAAAAAAAEA
// 	MgAAAAEAWgAAAAYAAAAAAAEANQAAAAEALQAAAAYAAAAAAAE4QklNBBQAAAAAAAQAAAABOEJJTQQM
// 	...

// ----------------------------------------------------------------------------------
// To do chacha20 encryption, just change the settings:

CkCrypt2_putCryptAlgorithm(crypt,'chacha20');
CkCrypt2_putKeyLength(crypt,256);
// The initial count is the initial block counter for the chacha20 algorithm.
// It can be any integer, but must be set to the same when decrypting.
CkCrypt2_putInitialCount(crypt,22);

success := CkCrypt2_EncryptBd(crypt,jpgBytes);
// jpgBytes now contains chacha20 encrypted bytes.

success := CkCrypt2_DecryptBd(crypt,jpgBytes);
// jpgBytes is now restored back to the original unencrypted by bytes.

// Save the bytes to a file..
success := CkBinData_WriteFile(jpgBytes,'qa_output/starfish.jpg');

Memo1.Lines.Add('Success.');

CkBinData_Dispose(jpgBytes);
CkCrypt2_Dispose(crypt);

end;