Pascal (Lazarus/Delphi)

CoSign PKCS7/CMS Signed Data

See more Digital Signatures Examples

Demonstrates how to add a 2nd signature to a CMS SignedData. This is to add an additional signature, SignerInfo and certificate(s) to an existing CMS signed data.

In this example, we cosign an existing pdf.p7s

Note: The CoSign method is added in Chilkat v9.5.0.89.

Pascal (Lazarus/Delphi)

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.BinData,
  Chilkat.Cert,
  Chilkat.Crypt2;

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

procedure RunDemo;
var
  success: Boolean;
  crypt: TCrypt2;
  cert: TCert;
  bd: TBinData;
  bd2: TBinData;

begin
  success := False;

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

  crypt := TCrypt2.Create;
  cert := TCert.Create;

  //  If loading from a smart card, set the smartcard PIN.
  cert.SmartCardPin := '0000';

  //  Load a certificate in some way, such as from a smart card.
  //  Chilkat provides other methods to load from a .pfx, .pem, or from the Windows certificate stores..
  success := cert.LoadFromSmartcard('');
  if (success = False) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;

  success := crypt.SetSigningCert(cert);
  if (success = False) then
    begin
      WriteLn(crypt.LastErrorText);
      Exit;
    end;

  //  Load the file to be co-signed.
  //  NOTE:  This is to cosign a PDF file contained within a CMS (PKCS7) message.
  //  (In other words, the PDF is contained within the CMS SignedData, rather than the other way around
  //  where a CMS signature is contained within a PDF.  Use Chilkat's PDF class to sign a PDF, which is
  //  to embed a CMS signature within the PDF.)
  bd := TBinData.Create;
  success := bd.LoadFile('qa_data/p7s/cosign/sample.pdf.p7s');
  if (success = False) then
    begin
      WriteLn('Failed to load pdf.p7s input file.');
      Exit;
    end;

  //  bd2 will contain the co-signed result.
  bd2 := TBinData.Create;
  success := crypt.CoSign(bd,cert,bd2);
  if (success = False) then
    begin
      WriteLn(crypt.LastErrorText);
      Exit;
    end;

  success := bd.WriteFile('qa_output/cosigned.pdf.p7s');
  if (success = False) then
    begin
      WriteLn('Failed to save pdf.p7s output file.');
      Exit;
    end;

  WriteLn('Success!');


  crypt.Free;
  cert.Free;
  bd.Free;
  bd2.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.