Pascal (Lazarus/Delphi)

PKCS11 Find Certificate with Key Usage on Smart Card or USB Token

See more PKCS11 Examples

Demonstrates how to find and return the 1st certificate on a smart card or USB token with a desired intended key usage.

Note: This example requires Chilkat v9.5.0.91 or later.

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.Pkcs11;

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

procedure RunDemo;
var
  success: Boolean;
  pkcs11: TPkcs11;
  slotID: Integer;
  readWrite: Boolean;
  userType: Integer;
  pin: string;
  cert: TCert;

begin
  success := False;

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

  //  Note: Chilkat's PKCS11 implementation runs on Windows, Linux, Mac OS X, and other supported operating systems.

  pkcs11 := TPkcs11.Create;

  pkcs11.SharedLibPath := 'aetpkss1.dll';

  success := pkcs11.Initialize();
  if (success = False) then
    begin
      WriteLn(pkcs11.LastErrorText);
      Exit;
    end;

  //  Pass -1 for the slotID to open a session on the first non-empty slot.
  slotID := -1;

  //  Open a session.
  readWrite := True;
  success := pkcs11.OpenSession(slotID,readWrite);
  if (success = False) then
    begin
      WriteLn(pkcs11.LastErrorText);
      Exit;
    end;

  //  Make it an authenticated session by calling Login.
  //  
  //  If we don't authenticate, then we won't be able to see the private keys, and thus
  //  we won't know which certificates have an associated private key stored on the smart card.

  //  The smart card PIN is passed to the Login method.
  //  userType 1 indicates a "Normal User".
  userType := 1;
  pin := '0000';
  success := pkcs11.Login(userType,pin);
  if (success = False) then
    begin
      WriteLn(pkcs11.LastErrorText);
      success := pkcs11.CloseSession();
      Exit;
    end;

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

  cert := TCert.Create;

  //  Find a certificate with an intended key usage.
  //  Possible key usages to find are:
  //  
  //  DigitalSignature
  //  NonRepudiation
  //  KeyEncipherment
  //  DataEncipherment
  //  CertificateSigning
  //  CrlSigning
  //  
  //  To find a cert having any one of several usages, pass a comma-separated list of usages:
  success := pkcs11.FindCert('keyUsage','NonRepudiation,DigitalSignature',cert);
  if (success = True) then
    begin
      WriteLn('Cert with private key: ' + cert.SubjectCN);
    end
  else
    begin
      WriteLn('No certificates having the intended key usage were found.');
    end;

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

  //  Revert to an unauthenticated session by calling Logout.
  success := pkcs11.Logout();
  if (success = False) then
    begin
      WriteLn(pkcs11.LastErrorText);
      success := pkcs11.CloseSession();
      Exit;
    end;

  //  When finished, close the session.
  //  It is important to close the session (memory leaks will occur if the session is not properly closed).
  success := pkcs11.CloseSession();
  if (success = False) then
    begin
      WriteLn(pkcs11.LastErrorText);
      Exit;
    end;

  WriteLn('Success.');


  pkcs11.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.