Using a self signed cert with Nginx

After the recent heart bleed incident (which I’m sure many of you well remember) I had to reassign some certificates. It turns out that this was a great opportunity to create a blog post.  Since I do not create and assign certs very frequently it is a good opportunity to take some notes and hopefully ease the process for others.  After patching the vulnerable version of Openssl, there are really only a few steps needed to accomplish this.  Assuming you already have nginx installed, which is trivial to do on Ubuntu, the first step is to create the necessary crt and key files.

sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/nginx/cert.key -out /etc/nginx/cert.crt

Next you will need to tell nginx to load up you new certs in its config.  Here is an example of what the server block in you /etc/nginx/site-available config might look like.  Notice the ssl_certificate and ssl_certificate_key files correspond to the cert files we created above, which we stuck in the /etc/nginx directory.  If you decide to place these certs in a different location you will need to modify your config file to reflect the location.

server {

listen *:443; 
ssl on; 
ssl_certificate cert.crt; 
ssl_certificate_key cert.key; 
ssl_session_timeout 5m; 
ssl_protocols SSLv3 TLSv1; 
ssl_ciphers ALL:!ADH:!EXPORT56:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv3:+EXP; 
ssl_prefer_server_ciphers on;

}

Just to cover all our bases here we will also redirect any requests that come in to port 80 (default web) back to 443 for ssl.  The is a simple addition and will add an additional layer of security.

server { 
listen 80; 
return 301 https://$host$request_uri; 
}

The final step is to reload your configuration and test to make sure everything works.

sudo service nginx reload

If your nginx fails to reload, more than likely there is some sort of configuration or syntax error in your config file.  Comb through it for any potential errors or mistakes.  Once your config is loaded properly you can check your handy work by attempting to hit your site using http://.  If your config is working properly it should automatically redirect you to https://.

That’s all it takes.  I think it might be a good exercise to try something like this with Chef but for now this process works okay by hand.  Let me know what you think or if this can be improved.

Liked it? Support me on Patreon

Josh Reichardt

Josh is the creator of this blog, a system administrator and a contributor to other technology communities such as /r/sysadmin and Ops School. You can also find him on Twitter and Facebook.