Pascal (Lazarus/Delphi)

PKCS7 Sign Text using RSA 2048, SHA256, Base64 Output

See more Digital Signatures Examples

Demonstrates how to sign text using 2048-bit RSA with SHA256, producing PKCS#7 output in Base64. The certificate w/ private key used for signing is loaded from a .p12/.pfx file. 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.Cert,
  Chilkat.Crypt2;

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

procedure RunDemo;
var
  success: Boolean;
  cert: TCert;
  crypt: TCrypt2;
  textToSign: string;
  sigBase64: string;

begin
  success := False;

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

  cert := TCert.Create;

  //  Load the cert and private key.  Whatever the private key happens to be,
  //  such as RSA or ECC, then Chilkat will use it.  If the private key is 
  //  a 2048-bit RSA key, then that's what will be used..
  success := cert.LoadPfxFile('qa_data/pfx/myCertAndKey.p12','password');
  if (success <> True) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;

  crypt := TCrypt2.Create;

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

  //  Use SHA-256
  crypt.HashAlgorithm := 'sha256';

  //  Hash the utf-8 byte representation of the string
  crypt.Charset := 'utf-8';

  //  Return the result in base64
  crypt.EncodingMode := 'base64';

  //  Sign some text..
  textToSign := 'This is the text to be hashed and signed.';
  sigBase64 := crypt.OpaqueSignStringENC(textToSign);
  if (crypt.LastMethodSuccess <> True) then
    begin
      WriteLn(crypt.LastErrorText);
      Exit;
    end;

  WriteLn(sigBase64);

  //  The result:
  //  MIIS2wYJKoZIhvcNAQc ... zGeeY4Oxg==


  cert.Free;
  crypt.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.