# /var/ssl/ssl.conf
## Used in multiple SSL server blocks ##
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# enable session resumption to improve https performance
# http://vincent.bernat.im/en/blog/2011-ssl-session-reuse-rfc5077.html
ssl_session_cache shared:SSL:50m;
ssl_session_timeout 5m;

# Diffie-Hellman parameter for DHE ciphersuites, recommended 2048 bits
ssl_dhparam /etc/nginx/cert/dhparam.pem;

# enables server-side protection from BEAST attacks
# http://blog.ivanristic.com/2013/09/is-beast-still-a-threat.html
ssl_prefer_server_ciphers on;

# disable SSLv3(enabled by default since nginx 0.8.19) since it's less secure then TLS http://en.wikipedia.org/wiki/Secure_Sockets_Layer#SSL_3.0
ssl_protocols TLSv1 TLSv1.1 TLSv1.2;

# ciphers chosen for forward secrecy and compatibility
# http://blog.ivanristic.com/2013/08/configuring-apache-nginx-and-openssl-for-forward-secrecy.html
ssl_ciphers "ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-SHA:ECDHE-RSA-AES128-SHA:DHE-RSA-AES256-SHA256:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA:DHE-RSA-AES128-SHA:ECDHE-RSA-DES-CBC3-SHA:EDH-RSA-DES-CBC3-SHA:AES256-GCM-SHA384:AES128-GCM-SHA256:AES256-SHA256:AES128-SHA256:AES256-SHA:AES128-SHA:DES-CBC3-SHA:HIGH:!aNULL:!eNULL:!EXPORT:!DES:!MD5:!PSK:!RC4";

# enable ocsp stapling (mechanism by which a site can convey certificate revocation information to visitors in a privacy-preserving, scalable manner)
# http://blog.mozilla.org/security/2013/07/29/ocsp-stapling-in-firefox/
resolver 8.8.8.8;
ssl_stapling on;

# config to enable HSTS(HTTP Strict Transport Security) https://developer.mozilla.org/en-US/docs/Security/HTTP_Strict_Transport_Security
# to avoid ssl stripping https://en.wikipedia.org/wiki/SSL_stripping#SSL_stripping
add_header Strict-Transport-Security "max-age=31536000; includeSubdomains;";

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