psk_find_session_callback() for this purpose instead. If TLSv1.3 has been negotiated then OpenSSL will first check to see if a callback has been set via SSL_CTX_set_psk_find_session_callback() or SSL_set_psk_find_session_callback() and it will use that in preference. If no such callback is present then it will check to see if a callback has been set via SSL_CTX_set_psk_server_callback() or SSL_set_psk_server_callback() and use that. In this case the handshake digest will default to SHA-256 for any returned 