Chapter 4. Red Hat build of OpenJDK features

The latest Red Hat build of OpenJDK 11 release might include new features. Additionally, the latest release might enhance, deprecate, or remove features that originated from previous Red Hat build of OpenJDK 11 releases.

Red Hat build of OpenJDK new features and enhancements

Review the following release notes to understand new features and feature enhancements that Red Hat build of OpenJDK 11.0.24 provides:

DTLS 1.0 is disabled by default

OpenJDK 9 introduced support for both version 1.0 and version 1.2 of the Datagram Transport Layer Security (DTLS) protocol (JEP-219). DTLSv1.0, which is based on TLS 1.1, is no longer recommended for use, because this protocol is considered weak and insecure by modern standards. In Red Hat build of OpenJDK 11.0.24, if you attempt to use DTLSv1.0, the JDK throws an SSLHandshakeException by default.

If you want to continue using DTLSv1.0, you can remove DTLSv1.0 from the jdk.tls.disabledAlgorithms system property either by modifying the java.security configuration file or by using the java.security.properties system property.

See JDK-8256660 (JDK Bug System).

RPATH preferred over RUNPATH for $ORIGIN runtime search paths in internal JDK binaries

Native executables and libraries in the JDK use embedded runtime search paths (rpaths) to locate required internal JDK native libraries. On Linux systems, binaries can specify these search paths by using either DT_RPATH or DT_RUNPATH.

If a binary specifies search paths by using DT_RPATH, these paths are searched before any paths that are specified in the LD_LIBRARY_PATH environment variable. If a binary specifies search paths by using DT_RUNPATH, these paths are searched only after paths that are specified in LD_LIBRARY_PATH. This means that the use of DT_RUNPATH can allow JDK internal libraries to be overridden by any libraries of the same name that are specified in LD_LIBRARY_PATH, which is undesirable from a security perspective.

In earlier releases, the type of runtime search path used was based on the default search path for the dynamic linker. In Red Hat build of OpenJDK 11.0.24, to ensure that DT_RPATH is used, the --disable-new-dtags option is explicitly passed to the linker.

See JDK-8326891 (JDK Bug System).

GlobalSign R46 and E46 root certificates added

In Red Hat build of OpenJDK 11.0.24, the cacerts truststore includes two GlobalSign TLS root certificates:

See JDK-8316138 (JDK Bug System).