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Delphi ActiveX

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.

Chilkat Delphi ActiveX Downloads

Delphi ActiveX
uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Integer;
pkcs11: TChilkatPkcs11;
slotID: Integer;
readWrite: Integer;
userType: Integer;
pin: WideString;
cert: TChilkatCert;

begin
success := 0;

// 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 := TChilkatPkcs11.Create(Self);

pkcs11.SharedLibPath := 'aetpkss1.dll';

success := pkcs11.Initialize();
if (success = 0) then
  begin
    Memo1.Lines.Add(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 := 1;
success := pkcs11.OpenSession(slotID,readWrite);
if (success = 0) then
  begin
    Memo1.Lines.Add(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 = 0) then
  begin
    Memo1.Lines.Add(pkcs11.LastErrorText);
    success := pkcs11.CloseSession();
    Exit;
  end;

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

cert := TChilkatCert.Create(Self);

// 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.ControlInterface);
if (success = 1) then
  begin
    Memo1.Lines.Add('Cert with private key: ' + cert.SubjectCN);
  end
else
  begin
    Memo1.Lines.Add('No certificates having the intended key usage were found.');
  end;

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

// Revert to an unauthenticated session by calling Logout.
success := pkcs11.Logout();
if (success = 0) then
  begin
    Memo1.Lines.Add(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 = 0) then
  begin
    Memo1.Lines.Add(pkcs11.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add('Success.');
end;