Java Requires Chilkat v10.1.2+

RSA Sign String using Private Key of Certificate Type A3 (smart card / token)

See more RSA Examples

Demonstrates RSA signing a string using the private key of a certificate type A3 (smart card, token).

Note: This is a Windows-only example.

Chilkat2 Java

import com.chilkatsoft.chilkat2.Cert;
import com.chilkatsoft.chilkat2.CertStore;
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.JsonObject;
import com.chilkatsoft.chilkat2.Rsa;

public class ChilkatExample {

    public static void main(String[] args) {
        // First get the A3 certificate that was installed on the Windows system.
        CertStore certStore = new CertStore();

        String thumbprint = "12c1dd8015f3f03f7b1fa619dc24e2493ca8b4b2";

        // This is specific to Windows because it is opening the Windows Current-User certificate store.
        boolean bReadOnly = true;
        try {
            certStore.openCurrentUserStore(bReadOnly);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Find the certificate with the desired thumbprint
        // (There are many ways to locate a certificate.  This example chooses to find by thumbprint.)
        JsonObject json = new JsonObject();
        json.updateString("thumbprint", thumbprint);

        Cert cert = new Cert();
        try {
            certStore.findCert(json, cert);
        } catch (ChilkatException e) {
            System.out.println("Failed to find the certificate.");
            return;
        }

        System.out.println("Found: " + cert.getSubjectCN());

        Rsa rsa = new Rsa();

        // Provide the cert's private key
        boolean bUsePrivateKey = true;
        String sigBase64;
        try {
            rsa.setX509Cert(cert, bUsePrivateKey);

            // Return the RSA signature in base64 encoded form.
            rsa.setEncodingMode("base64");

            // Sign the utf-8 byte representation of the string.
            rsa.setCharset("utf-8");

            // You can also choose other hash algorithms, such as SHA-1.
            sigBase64 = rsa.signStringENC("text to sign", "SHA-256");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("Base64 signature: " + sigBase64);
    }
}