apply @konklone's nginx https: recommendations from https://gist.github.com/konklone/6532544

conf/nginx.conf

@@ -30,6 +30,15 @@ server {
 	ssl_certificate $STORAGE_ROOT/ssl/ssl_certificate.pem;
 	ssl_certificate_key $STORAGE_ROOT/ssl/ssl_private_key.pem;
 
+	# SSL configuration by @konklone at https://gist.github.com/konklone/6532544
+	# 1) prefer certain ciphersuites, to enforce Perfect Forward Secrecy and avoid known vulnerabilities. http://ggramaize.wordpress.com/2013/08/02/tls-perfect-forward-secrecy-support-with-apache/ and https://www.ssllabs.com/ssltest/analyze.html
+	ssl_prefer_server_ciphers on;
+	ssl_ciphers ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-RC4-SHA:ECDHE-RSA-AES256-SHA:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-SHA256:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA:DHE-RSA-AES128-SHA:RC4-SHA:AES256-GCM-SHA384:AES256-SHA256:CAMELLIA256-SHA:ECDHE-RSA-AES128-SHA:AES128-GCM-SHA256:AES128-SHA256:AES128-SHA:CAMELLIA128-SHA;
+	# 2) turn on session resumption, using a 10 min cache shared across nginx processes, as recommended by http://nginx.org/en/docs/http/configuring_https_servers.html
+	ssl_session_cache   shared:SSL:10m;
+	ssl_session_timeout 10m;
+	keepalive_timeout   70;	
+
 	# We'll expose the same static directory under https.
 	root $STORAGE_ROOT/www/static;