Question

I am further toward getting this SSL connection working but if someone could tell me why my applet is triggering a ‘sslv3 alert certificate unknown” error that would be great. I found this error by running “openssl s_server” and (trying) to connect to it using my Java client. I will include the source for the program. I heard it could be the lack of a trust store but I created one and it didn’t help.

public class first extends JApplet  {

    PrintWriter toServer = null;
    BufferedReader fromServer = null;

    public void init() {

        System.setProperty("javax.net.ssl.keyStore", "javakeys");
        System.setProperty("javax.net.ssl.keyStorePassword", "javakeys");
        System.setProperty("javax.net.ssl.trustStore", "truststore.ts"); 
        System.setProperty("javax.net.ssl.trustStorePassword", "javakeys"); 

try {

        SSLSocketFactory sslsocketfactory = (SSLSocketFactory) SSLSocketFactory.getDefault();
        SSLSocket sslsocket = (SSLSocket) sslsocketfactory.createSocket("localhost", 4000);

        toServer = new PrintWriter(sslsocket.getOutputStream(), true);

        toServer.println("Flystar\n\r");

        InputStreamReader isr = new InputStreamReader(sslsocket.getInputStream());
        fromServer = new BufferedReader(isr, 1);

        JOptionPane.showMessageDialog( null, fromServer );


    } catch (Exception exception) {
            exception.printStackTrace();
    }

//      toServer.println("Flystar".getBytes());

    }

    public void paint(Graphics g) {

        g.setColor( Color.red );
        g.drawString("Welcome to Java!!", 50, 60 );
    }


}

Thanks,
-Roland

Answer 1

“sslv3 alert certificate unknown” means that the server’s certificate is in a format that your Java client doesn’t understand.