Hello, Sorry if question has already been asked, I saw https://github.com/openssl/openssl/issues/3029 . Issue#3029 is a mixed discussion on both tls-1.2 extension "trusted CA indication" (rfc6066#section-6) and TLS-1.3 "Certificate Authorities", thus conclusion is unclear.
tests done : openssl version used : openssl-1.1.1a client : "openssl s_client ... -requestCAfile .." ; tls extension in client Hello is present. serverside : 'openssl s_server' using certfile which has 2 root-CA+cert (certA and certB) and keyfile which has both secrets. Whatever the client sends in Certificate Authorities, s_server chooses the first leaf certificate found within certfile. Questions : is rfc8446#section-4.2.4 is not mandatory featuyre of tls-1.3. Does openssl iimplements it fully ? If yes, how to test ? br, Alexandre.
