Sample code for 30+ languages & platforms
Java

Load Certificate from Smart Card by Key Usage

See more Certificates Examples

You may have a smartcard or USB token that contains only 2 certificates, one for signing, and one for authentication, and you wish to load the certificate for signing. This example demonstrates how to load the 1st certificate found on a smartcard that matches the intended key usage.

Chilkat Java Downloads

Java
import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

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

    CkCert cert = new CkCert();

    // If you know the smart card PIN, set it prior to loading from the smartcard/USB token.
    cert.put_SmartCardPin("12345678");

    // To load a certificate matching an intended key usage, specify the type of usage as shown below.
    // 
    // The possible key usage keywords are:
    // 
    // digitalsignature
    // Use when the public key is used with a digital signature mechanism to support security services other than non-repudiation, certificate signing, or CRL signing. 
    // A digital signature is often used for entity authentication and data origin authentication with integrity.

    // nonrepudiation
    // When a digital certificate's key usage includes "nonrepudiation," it implies that the certificate and its associated private key can be used to 
    // create digital signatures that provide proof of the origin and integrity of the signed data, and the signer cannot later deny having signed the data.

    // Other less common usages:

    // certificatesigning
    // keyencipherment
    // dataencipherment
    // crlsigning
    // secureemail
    // serverauthentication
    // clientauthentication
    // codesigning
    // timestamping

    success = cert.LoadFromSmartcard("keyusage=nonrepudiation");
    if (success == false) {
        System.out.println(cert.lastErrorText());
        System.out.println("Certificate not loaded.");
        return;
        }

    System.out.println("Found: " + cert.subjectDN() + " serial=" + cert.serialNumber());
  }
}