The "supported_groups" extension in ServerHellos

Reported in OpenJDK:
http://mail.openjdk.java.net/pipermail/security-dev/2018-August/018005.html
----------
While testing the recently released RC of JDK11 against the Apache Ant
project, I happened to run into an odd error. I have now been able to
reproduce this using the following, pretty trivial code:

import java.net.URL;
import java.io.InputStream;

public class Fetch {
     public static void main(final String[] args) throws Exception {
         final URL targetURL = new
URL("https://repository.jboss.org/nexus/content/groups/public/javax/media/jai-core/1.1.3/jai-core-1.1.3.pom");
         try (final InputStream is =
targetURL.openConnection().getInputStream()) {
             is.read();
         }
         System.out.println("Done");
     }
}

All it does is opens a (HTTPS) connection against an endpoint to read
some content. This code works fine in Java 8 and even Java 10. I'm
pretty sure this was working fine even in Java 11 early access builds,
but I don't have any such build/binary at hand to be certain.

However, using the latest (OpenJDK) RC of Java 11 (both on Mac OS and
Linux) downloaded from[1]:

openjdk version "11" 2018-09-25
OpenJDK Runtime Environment 18.9 (build 11+28)
OpenJDK 64-Bit Server VM 18.9 (build 11+28, mixed mode)

it fails with:


Exception in thread "main" javax.net.ssl.SSLHandshakeException:
extension (10) should not be presented in server_hello
    at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:128)
    at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:117)
    at
java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:308)
    at
java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:264)
    at
java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:255)
    at
java.base/sun.security.ssl.SSLExtensions.<init>(SSLExtensions.java:71)
    at
java.base/sun.security.ssl.ServerHello$ServerHelloMessage.<init>(ServerHello.java:173)
    at
java.base/sun.security.ssl.ServerHello$ServerHelloConsumer.consume(ServerHello.java:864)
    at
java.base/sun.security.ssl.SSLHandshake.consume(SSLHandshake.java:392)
    at
java.base/sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:444)
    at
java.base/sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:421)
    at
java.base/sun.security.ssl.TransportContext.dispatch(TransportContext.java:178)
    at java.base/sun.security.ssl.SSLTransport.decode(SSLTransport.java:164)
    at
java.base/sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:1152)
    at
java.base/sun.security.ssl.SSLSocketImpl.readHandshakeRecord(SSLSocketImpl.java:1063)
    at
java.base/sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:402)
    at
java.base/sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:567)
    at
java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:185)
    at
java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1581)
    at
java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1509)
    at
java.base/sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:245)
    at Fetch.main(Fetch.java:7)


[1] http://jdk.java.net/11/

-Jaikiran


http://mail.openjdk.java.net/pipermail/security-dev/2018-August/018006.html
-------------
As noted in that exception message, it appears that the server is
sending a "supported_groups" extension in its ServerHello message
(TLSv1.2). Reading about it, this seems to be a common issue with
certain servers and certain SSL implementations have added support to be
lenient with such servers https://github.com/openssl/openssl/pull/4463/files