(Delphi DLL) Encrypt File using X.509 Certificate using AES in CBC Mode

Demonstrates how to encrypt a file using an X.509 Certificate's public key, where the underlying bulk encryption algorithm is 128-bit AES in CBC mode. (The underlying bulk encryption algorithm can be specified to be other algorithms/strengths.)

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, Cert, Crypt2;

...

procedure TForm1.Button1Click(Sender: TObject);
var
crypt: HCkCrypt2;
cert: HCkCert;
success: Boolean;

begin
//  This example requires the Chilkat Crypt API to have been previously unlocked.
//  See Unlock Chilkat Crypt for sample code.

crypt := CkCrypt2_Create();

//  Use public-key cryptography for encryption.
CkCrypt2_putCryptAlgorithm(crypt,'pki');

//  Get an X.509 certificate to use for encrypting.
//  Note: Chilkat provides many different ways of loading a certificate, from many different formats,
//  or if on Windows, from the installed certificates on the system.
//  This example simply loads a certificate from a file.
//  Also, for encryption, only the public key is needed.  Digital certificates embed the public key
//  within the X.509 format itself.  Therefore, if you have a certificate, you also have the public key.
cert := CkCert_Create();
success := CkCert_LoadFromFile(cert,'qa_data/certs/testCert.cer');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(cert));
    Exit;
  end;

success := CkCrypt2_SetEncryptCert(crypt,cert);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCrypt2__lastErrorText(crypt));
    Exit;
  end;

//  Indicate the underlying bulk encryption algorithm to be used:
CkCrypt2_putPkcs7CryptAlg(crypt,'aes');
CkCrypt2_putKeyLength(crypt,128);

//  Note: When doing public-key encryption the underlying bulk symmetric cipher mode will always be CBC. (at least with Chilkat...)

//  There's one last option that could be set.  If is the RSA encryption encryption/padding scheme.
//  By default, RSAES_PKCS1-V1_5 is used.  If desired, the OaepPadding property could be set to True to
//  use RSAES_OAEP.  (We'll leave it set at the default value of False)
CkCrypt2_putOaepPadding(crypt,False);

//  Everything is specified.  Now just encrypt...
//  The output is PKCS7 in binary DER format.
success := CkCrypt2_CkEncryptFile(crypt,'qa_data/hamlet.xml','qa_output/hamlet.p7');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkCrypt2__lastErrorText(crypt));
    Exit;
  end;

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

CkCrypt2_Dispose(crypt);
CkCert_Dispose(cert);

end;