Create an Opaque Signature with a Separate Private Key

See more MIME Examples

Demonstrates the Chilkat Mime.ConvertToSignedPk method, which creates an opaque signature using a signer certificate and its separately supplied private key. The first argument is the Cert and the second is the PrivateKey.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.Mime,
  Chilkat.PrivateKey,
  Chilkat.Cert;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  mime: TMime;
  cert: TCert;
  privKey: TPrivateKey;

begin
  success := False;

  mime := TMime.Create;
  success := mime.SetBodyFromPlainText('This message will be signed.');
  if (success = False) then
    begin
      WriteLn(mime.LastErrorText);
      Exit;
    end;
  //  Load the certificate and its private key separately.
  cert := TCert.Create;
  success := cert.LoadFromFile('qa_data/signer.cer');
  if (success = False) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;

  privKey := TPrivateKey.Create;
  success := privKey.LoadPemFile('qa_data/signer_privkey.pem');
  if (success = False) then
    begin
      WriteLn(privKey.LastErrorText);
      Exit;
    end;

  //  Create an opaque signature when the certificate and private key are supplied separately.  The
  //  1st argument is the signer certificate and the 2nd is its private key.
  success := mime.ConvertToSignedPk(cert,privKey);
  if (success = False) then
    begin
      WriteLn(mime.LastErrorText);
      Exit;
    end;

  success := mime.SaveMime('qa_output/signed_opaque.eml');
  if (success = False) then
    begin
      WriteLn(mime.LastErrorText);
      Exit;
    end;
  WriteLn('Message converted to an opaque signed message.');


  mime.Free;
  cert.Free;
  privKey.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.