nginx-ssl.conf

# We track the Mozilla "intermediate" compatibility TLS recommendations.
# Note that these settings are repeated in the SMTP and IMAP configuration.
# ssl_protocols has moved to nginx.conf in bionic, check there for enabled protocols.
ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384;
ssl_dhparam STORAGE_ROOT/ssl/dh2048.pem;

# as recommended by http://nginx.org/en/docs/http/configuring_https_servers.html
ssl_session_cache shared:SSL:50m;
ssl_session_timeout 1d;

# Buffer size of 1400 bytes fits in one MTU.
# nginx 1.5.9+ ONLY
ssl_buffer_size 1400; 

ssl_stapling on;
ssl_stapling_verify on;
resolver 127.0.0.1 valid=86400;
resolver_timeout 10;

# h/t https://gist.github.com/konklone/6532544