SSL/TLS settings for exim4

tls_certificate = /etc/exim4/ssl/exim.cert
tls_privatekey = /etc/exim4/ssl/exim.key
tls_advertise_hosts = *
tls_require_ciphers = ECHACHA20+POLY1305:ECDH+AESGCM:EDH+AESGCM
openssl_options = +no_sslv2 +no_sslv3