Dart

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.

Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // 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.

  final pkcs11 = CkPkcs11();

  pkcs11.sharedLibPath = 'aetpkss1.dll';

  try {
    pkcs11.initialize();
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

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

  // Open a session.
  final readWrite = true;
  try {
    pkcs11.openSession(slotID, readWrite);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // 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".
  final userType = 1;
  final pin = '0000';
  try {
    pkcs11.login(userType, pin);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    pkcs11.closeSession();
    return;
  }

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

  final cert = CkCert();

  // 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:
  try {
    pkcs11.findCert('keyUsage', 'NonRepudiation,DigitalSignature', cert);
    print('Cert with private key: ${cert.subjectCN}');
  } on ChilkatException {
    print('No certificates having the intended key usage were found.');
  }

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

  // Revert to an unauthenticated session by calling Logout.
  try {
    pkcs11.logout();
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    pkcs11.closeSession();
    return;
  }

  // When finished, close the session.
  // It is important to close the session (memory leaks will occur if the session is not properly closed).
  try {
    pkcs11.closeSession();
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('Success.');
}