SimpleBlockingServer.java

package tlschannel.example;

import tlschannel.ServerTlsChannel;
import tlschannel.TlsChannel;

import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.TrustManagerFactory;
import java.io.IOException;
import java.io.InputStream;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.security.GeneralSecurityException;
import java.security.KeyStore;


/**
 * <p> Server example. Accepts one connection and echos bytes sent by the client into standard output.</p>
 * <p> To test, use: </p>
 * <code>
 * openssl s_client -connect localhost:10000
 * </code>
 */
public class SimpleBlockingServer {

    private static final Charset utf8 = StandardCharsets.UTF_8;

    public static void main(String[] args) throws IOException, GeneralSecurityException {

        // initialize the SSLContext, a configuration holder, reusable object
        SSLContext sslContext = authenticatedContext("TLSv1.2");

        // connect server socket channel normally
        try (ServerSocketChannel serverSocket = ServerSocketChannel.open()) {
            serverSocket.socket().bind(new InetSocketAddress(10000));

            // accept raw connections normally
            System.out.println("Waiting for connection...");
            try (SocketChannel rawChannel = serverSocket.accept()) {

                // create TlsChannel builder, combining the raw channel and the SSLEngine, using minimal options
                ServerTlsChannel.Builder builder = ServerTlsChannel.newBuilder(rawChannel, sslContext);

                // instantiate TlsChannel
                try (TlsChannel tlsChannel = builder.build()) {

                    // write to stdout all data sent by the client
                    ByteBuffer res = ByteBuffer.allocate(10000);
                    while (tlsChannel.read(res) != -1) {
                        res.flip();
                        System.out.print(utf8.decode(res).toString());
                        res.compact();
                    }
                }
            }
        }
    }

    static SSLContext authenticatedContext(String protocol) throws GeneralSecurityException, IOException {
        SSLContext sslContext = SSLContext.getInstance(protocol);
        KeyStore ks = KeyStore.getInstance("JKS");
        try (InputStream keystoreFile =
                     SimpleBlockingServer.class.getClassLoader().getResourceAsStream("keystore.jks")) {
            ks.load(keystoreFile, "password".toCharArray());
            TrustManagerFactory tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
            tmf.init(ks);
            KeyManagerFactory kmf = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
            kmf.init(ks, "password".toCharArray());
            sslContext.init(kmf.getKeyManagers(), tmf.getTrustManagers(), null);
            return sslContext;
        }
    }
}