Setting cipher suite is possible using xpack.security.transport.ssl.cipher_suites, for example:
xpack.security.transport.ssl.cipher_suites: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
but there appears to be no setting to control the elliptic curve used for ephemeral Diffie–Hellman exchange. Is that correct or I am missing something?
As far as I know, there is no way in JSSE to set the preferred values for the supported_groups extension that is used in the TLS 1.3 ( or elliptic_curves as it used to be called in TLS 1.2 ) handshake to denote this.
You can probably set this as a JVM property in jvm.properties using the jdk.tls.namedGroups system property that is available since 8u21. Note that setting this will not only affect ECDHE but also ECDSA too.
Apache, Apache Lucene, Apache Hadoop, Hadoop, HDFS and the yellow elephant logo are trademarks of the Apache Software Foundation in the United States and/or other countries.