nginx ssl config with multiple SNI vhosts and A+ SSL Labs score as of 2014-11-05

README.md

Configuring nginx for SSL SNI vhosts

Gotchas

• Note that SHA2 hash algorithm may be not supported on older systems (Windows XP, Windows 2003, among others).
• Be aware that mandatory https on SNI vhosts eliminate [Internet Explorer on Windows XP, among others] (http://en.wikipedia.org/wiki/Server_Name_Indication#Web_browsers.5B6.5D).

Remarks

• My version of konklones SSL config does not have SPDY support(my nginx+openssl does not support it)
• You need a default ssl server (example.org-default.conf).
• Some SSL-options have to be unique across your instance, so it's easier to have them in a common file(ssl.conf).
• For updated ssl_ciphers, I refer you to these two sources
  • The original of this fork
  • The Mozilla SSL Config Generator

example.com.conf

server {
	listen		443	ssl;
	server_name	example.com;

	# required: path to certificate and private key
	ssl_certificate			/opt/keys/example.com/example.com.unified.crt;
	ssl_certificate_key		/opt/keys/example.com/example.com.decrypted.key;
		
	# required for OCSP stapling, if any of your vhosts don't have this line, you have to inactivate OCSP stapling in ssl.conf
	ssl_trusted_certificate		/opt/keys/example.com/example.com.unified+root.crt;

	# Include global SSL settings
	include /etc/nginx/ssl.conf;

	root   /usr/share/nginx/html;
	index  index.html index.htm;

	location / {
		proxy_pass  http://upstream;
	}
}

example.org-default.conf

server {
	listen		443	ssl    default_server;
	server_name	example.org;

	# required: path to certificate and private key
	ssl_certificate			/opt/keys/example.org/example.org.unified.crt;
	ssl_certificate_key		/opt/keys/example.org/example.org.decrypted.key;
	
	# required for OCSP stapling, if any of your vhosts don't have this line, you have to inactivate OCSP stapling in ssl.conf
	ssl_trusted_certificate		/opt/keys/example.org/example.org.unified+root.crt;

	# Include global SSL settings
	include /etc/nginx/ssl.conf;

	root   /usr/share/nginx/html;
	index  index.html index.htm;

	location / {
		proxy_pass  http://upstream;
	}
}

ssl.conf

# Basically the nginx configuration I use at konklone.com. 
# I check it using https://www.ssllabs.com/ssltest/analyze.html?d=konklone.com
#
# To provide feedback, please tweet at @konklone or email [email protected].
# Comments on gists don't notify the author. 
# 
# Thanks to WubTheCaptain (https://wubthecaptain.eu) for his help and ciphersuites.
# Thanks to Ilya Grigorik (https://www.igvita.com) for constant inspiration.

# HTTP Strict Transport Security: tells browsers to require https:// without first checking
# the http:// version for a redirect. Warning: it is difficult to change your mind.
#
#    max-age: length of requirement in seconds (31536000 = 1 year)
#    includeSubdomains: force SSL for *ALL* subdomains (remove if this is not what you want)
#    preload: indicates you want browsers to ship with HSTS preloaded for your domain.
#
#    Submit your domain for preloading in browsers at: https://hstspreload.appspot.com
#add_header Strict-Transport-Security 'max-age=31536000; includeSubDomains; preload';

# If you won't/can't turn on HTTPS for *all* subdomains, use this simpler version:
add_header Strict-Transport-Security 'max-age=31536000';

# Prefer certain ciphersuites, to enforce Forward Secrecy and avoid known vulnerabilities.
#
# Forces forward secrecy in all browsers and clients that can use TLS,
# but with a small exception (DES-CBC3-SHA) for IE8/XP users.
#
# Reference client: https://www.ssllabs.com/ssltest/analyze.html
ssl_prefer_server_ciphers on;
ssl_ciphers 'kEECDH+ECDSA+AES128 kEECDH+ECDSA+AES256 kEECDH+AES128 kEECDH+AES256 kEDH+AES128 kEDH+AES256 DES-CBC3-SHA +SHA !aNULL !eNULL !LOW !MD5 !EXP !DSS !PSK !SRP !kECDH !CAMELLIA !RC4 !SEED';

# Now let's really get fancy, and pre-generate a 2048 bit random parameter
# for DH elliptic curves. If not created and specified, default is only 1024 bits.
#
# Generated by OpenSSL with the following command:
#   openssl dhparam -outform pem -out dhparam2048.pem 2048
ssl_dhparam /path/to/dhparam2048.pem;

# Cut out the old, broken, insecure SSLv2 and SSLv3 entirely.
ssl_protocols TLSv1.2 TLSv1.1 TLSv1;


# optional: 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;

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

# OCSP stapling - means nginx will poll the CA for signed OCSP responses,
# and send them to clients so clients don't make their own OCSP calls.
# https://en.wikipedia.org/wiki/OCSP_stapling
#
# while the ssl_certificate above may omit the root cert if the CA is trusted,
# ssl_trusted_certificate below must point to a chain of **all** certs
# in the trust path - (your cert, intermediary certs, root cert)
#
# 8.8.8.8 and 8.8.4.4 below are Google's public IPv4 DNS servers.
# nginx will use them to talk to the CA.
ssl_stapling on;
ssl_stapling_verify on;
resolver 8.8.8.8 8.8.4.4 valid=86400;
resolver_timeout 10;