Delphi ActiveX

Duplicate openssl smime -decrypt -in some_file.dat.enc -binary -inform DER -inkey private.key -out some_file.dat

See more OpenSSL Examples

Demonstrates how to decrypt binary DER that was encrypted using the following openssl command:

openssl smime -encrypt -binary -aes-256-cbc -in some_file.dat -out some_file.dat.enc -outform DER cert.crt

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;
cert: TChilkatCert;
bd: TChilkatBinData;
privKey: TPrivateKey;
crypt: TChilkatCrypt2;

begin
success := 0;

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

// Duplicates the following openssl command:
// openssl smime -decrypt -in hello.txt.enc -binary -inform DER -inkey private.key -out hello.txt

cert := TChilkatCert.Create(Self);
success := cert.LoadFromFile('qa_data/openssl/EE.cer');
if (success = 0) then
  begin
    Memo1.Lines.Add(cert.LastErrorText);
    Exit;
  end;

bd := TChilkatBinData.Create(Self);
success := bd.LoadFile('qa_data/openssl/EE.key');
// Assuming success..

privKey := TPrivateKey.Create(Self);
success := privKey.LoadAnyFormat(bd.ControlInterface,'');
if (success = 0) then
  begin
    Memo1.Lines.Add(privKey.LastErrorText);
    Exit;
  end;

crypt := TChilkatCrypt2.Create(Self);
success := crypt.SetDecryptCert2(cert.ControlInterface,privKey.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(crypt.LastErrorText);
    Exit;
  end;

crypt.CryptAlgorithm := 'PKI';
success := crypt.CkDecryptFile('qa_data/openssl/hello.txt.enc','qa_output/hello.txt');
if (success = 0) then
  begin
    Memo1.Lines.Add(crypt.LastErrorText);
    Exit;
  end;

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