Decrypt S/MIME using a Certificate with Private Key Access

See more MIME Examples

Loads a CMS/PKCS #7 encrypted S/MIME message and decrypts it back to the original MIME content.

DecryptUsingCert takes a single certificate that already has access to its associated private key, for example a certificate loaded from a PFX.

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.Cert,
  Chilkat.Mime;

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

procedure RunDemo;
var
  success: Boolean;
  mime: TMime;
  pfxPassword: string;
  cert: TCert;
  body: string;

begin
  success := False;

  mime := TMime.Create;
  success := mime.LoadMimeFile('qa_data/encrypted.eml');
  if (success = False) then
    begin
      WriteLn(mime.LastErrorText);
      Exit;
    end;

  //  Decrypt using a certificate that already provides access to its private key (for example loaded
  //  from a PFX).  The only argument is the certificate.
  pfxPassword := 'myPfxPassword';
  cert := TCert.Create;
  success := cert.LoadPfxFile('qa_data/recipient.pfx',pfxPassword);
  if (success = False) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;

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

  body := mime.GetBodyDecoded();
  if (mime.LastMethodSuccess = False) then
    begin
      WriteLn(mime.LastErrorText);
      Exit;
    end;
  WriteLn(body);


  mime.Free;
  cert.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.