https://github.com/async-email/async-native-tls --- https://www.postgresql.org/docs/current/protocol-flow.html#id-1.10.5.7.11 https://dev.mysql.com/doc/dev/mysql-server/8.0.12/page_protocol_connection_phase.html#sect_protocol_connection_phase_initial_handshake_ssl_handshake
