SSLSocketClient.java #1

package testssl;

import java.io.IOException;
import javax.net.ssl.SSLSocket;
import javax.net.ssl.SSLSocketFactory;

/*
 * Test establishment of an SSL handshake multiple ways:  jdk default, TLSv1, TLSv1.1, and TLSv1.2
 */
public class SSLSocketClient {

    public static void main(String[] args) {

        if (args.length < 2) {
            printSyntax();
            System.exit(1);
        }
        int port = 0;
        try {
            port = Integer.parseInt(args[1]);
        } catch (NumberFormatException e) {
            System.out.println("Invalid port number: " + args[1]);
            printSyntax();
            System.exit(1);
        }
        
        String[] tlsList = new String[]{
            "", 
            "TLSv1", 
            "TLSv1.1", 
            "TLSv1.2",
            "TLSv1.3"}; 
        
        
        for (String tls : tlsList) {
            doHandshake(args[0], port, tls);
        }
    }

    private static void printSyntax() {
        System.out.println("Attempts an SSL Handshake to the provided host and port");
        System.out.println("Syntax:  SSLSocketClient host port");
        System.out.println("   sample:  SSLSocketClient google.com 443");
        System.out.println("   sample:  SSLSocketClient p4poke 1667");
    }

    public static void doHandshake(String host, int port, String tls) {
        SSLSocket socket = null;
        System.out.println("------------");
        System.out.println("Handshake to " + host + " port " + port);
        try {
            SSLSocketFactory factory;

            factory = TrustAllTrustManager.getSSLSocketFactory();

            socket = (SSLSocket)factory.createSocket(host, port);
            if (tls.length() > 0) {
                socket.setEnabledProtocols(new String[]{tls});
                System.out.println("Setting protocol to " + tls);
            } else {
                System.out.println("Not setting protocol:  using JVM default");
            }

            String[] enabledProtocols = socket.getEnabledProtocols();
            System.out.println("  Supported Protocol(s): " + String.join(",", enabledProtocols));


            socket.startHandshake();
            String protocol = socket.getSession().getProtocol();

            System.out.println("  --> success:  " + "Handshake to " + host + " port " + port + "; using " + protocol);

        } catch (IOException e) {
            e.printStackTrace(System.out);
            System.out.println("  --> fail: " + "Handshake to " + host + " port " + port);
        } finally {
            if (socket != null) {
                try {
                    socket.close();
                } catch (IOException e) {
                    // don't care.
                }
            }
        }
        System.out.println("-----------------");
    }
}