Securing Stash behind nginx using SSL

Please note that:

• We assume that you already have a running instance of nginx. If not, refer to the nginx documentation for instructions on downloading and installing nginx.
• SSL certificates must be installed on the server machine.
• Any existing links with other applications will need to be reconfigured using the new URL for Stash.
• Securing Git operations between the user's computer and Stash is a separate consideration - see Enabling SSH access to Git.

Be aware that Stash does not need to run behind a web server, since it is capable of serving web requests directly; to secure Stash when run in this way see Securing Stash with Tomcat using SSL. Otherwise, if you want to install Stash in an environment that incorporates nginx, this document is for you. (You can of course run Stash behind nginx without securing client connections to nginx using SSL – we don't describe this option on this page.)

Note that the Atlassian Support Offering does not cover nginx integration. Assistance with nginx may be obtained through the Atlassian community from answers.atlassian.com or from an Atlassian Expert.

Step 1: Configure the Tomcat Connector

Find the normal (non-SSL) Connector directive in Tomcat's server.xml file, and add the scheme ,  proxyName , and proxyPort attributes as shown below. Instead of mycompany.com, set the proxyName attribute to your domain name that the nginx server will be configured to serve. This informs Stash of the domain name and port of the requests that reach it via nginx, and is important to the correct operation of the Stash functions that construct URLs.

<Connector port="7990" 
     protocol="HTTP/1.1"
     connectionTimeout="20000"
     useBodyEncodingForURI="true"
     redirectPort="443"
     compression="on"
     compressableMimeType="text/html,text/xml,text/plain,text/css,application/json,application/javascript,application/x-javascript"
     secure="true"
     scheme="https"
     proxyName="mycompany.com" 
     proxyPort="443" />

For more information about configuring the Tomcat Connector, refer to the Apache Tomcat 7.0 HTTP Connector Reference.

Step 2: Set a context path for Stash

By default, Stash is configured to run with an empty context path; in other words, from the 'root' of the server's name space. In that default configuration, Stash would be accessed at:

http://mycompany.com:7990/

For the example configuration on this page, we want Stash to be accessed at: 

https://mycompany.com:7990/stash

In Tomcat's server.xml file, set the context path to /stash:

<Context path="/stash" docBase="${catalina.home}/atlassian-stash" reloadable="false" useHttpOnly="true">
    ....
</Context>

If you use a context path, it is important that the same path is:

• appended to the context path of Stash's base URL (Step 3).
• used when setting up the location for the proxy_pass directive (Step 4). 

Step 3: Change Stash's base URL

After re-starting Stash, open a browser window and log into Stash using an administrator account. Go to the Stash administration area and click Server settings (under 'Settings'), and change Base URL to match the proxy URL (the URL that the nginx server will be serving).

For this example, use http://mycompany.com:7990/stash  (Note the context path with this.)

Step 4: Configure nginx

Edit /etc/nginx/nginx.conf, using the example server configuration below, to configure nginx as a proxy server. 

Put the proxy_pass directive in the location block, and specify the protocol, name and port of the proxied server in the parameter (in our case, it is http://localhost:7990):

server {
	listen          443;
    server_name     mycompany.com;
	
	ssl                  	on;
    ssl_certificate      	<path/to/your/certificate>;
    ssl_certificate_key  	<path/to/your/certificate/key>;
    ssl_session_timeout  	5m;
    ssl_protocols  			SSLv3 TLSv1 TLSv1.1 TLSv1.2;
    ssl_ciphers  			RC4:HIGH:!aNULL:!MD5;
    ssl_prefer_server_ciphers   on;
    location /stash {
        proxy_pass 			http://localhost:7990/stash;
		proxy_set_header 	X-Forwarded-Host $host;
        proxy_set_header 	X-Forwarded-Server $host;
		proxy_set_header    X-Forwarded-For $proxy_add_x_forwarded_for;
		proxy_set_header    X-Real-IP $remote_addr;
		proxy_redirect 		off;
    }
}

Refer to http://nginx.org/en/docs/http/ngx_http_proxy_module.html.

Changes made in the configuration file will not be applied until the command to reload configuration is sent to nginx or it is restarted. To reload the configuration, execute:

nginx -s reload

This command should be executed under the same user that started nginx.

Resources

You may find the following resources helpful in setting up Stash behind nginx:

• http://nginx.org/en/docs/http/configuring_https_servers.html
• http://www.cyberciti.biz/tips/using-nginx-as-reverse-proxy.html
• https://mywushublog.com/2012/08/atlassian-tools-and-nginx/