OCSP Stapling

Online Certificate Status Protocol (OCSP) was created as an alternative to the Certificate Revocation List (CRL) protocol. Both protocols are used to check whether an SSL Certificate has been revoked. The CRL protocol requires the browser to spend time downloading and then searching a list for certificate information. With OCSP, the browser simply posts a query and receives a response from an OCSP responder (a Certificate Authority’s (CA's) server that specifically listens for and responds to OCSP requests) about the revocation status of a certificate.

OCSP stapling can be used to enhance the OCSP protocol by letting the webhosting site be more proactive in improving the client (browsing) experience. OCSP stapling allows the certificate presenter (i.e. web server) to query the OCSP responder directly and then cache the response. This securely-cached response is then delivered with the TLS/SSL handshake via the Certificate Status Request extension response, ensuring that the browser gets the same response performance for the certificate status as it does for the website content.

• Non-self-signed SSL Certificate
• Port 443 enabled for https
• If using Apache config, HTTPD Server 2.3.3+

Follow the same method as Apache through httpd.conf. See these external references for more information: digicert.com or globalsign.com

Add the following lines to:

1. For EA3: /usr/local/apache/conf/includes/pre_main_global.conf
2. For EA4: /etc/apache2/conf.d/includes/pre_main_global.conf

<IfModule Litespeed>
SSLStaplingCache shmcb:/tmp/stapling_cache(128000)
</IfModule>

Edit your site’s VirtualHost SSL configuration.

Add the following lines to:

1. For EA3: /usr/local/apache/conf/userdata/lscache_vhosts.conf
2. For EA4: /etc/apache2/conf.d/userdata/lscache_vhosts.conf

(if these directories do not exist, create them).

<IfModule Litespeed>
  SSLUseStapling on
</IfModule>

Apply these changes to all Virtual Hosts by running the following command:

/scripts/ensure_vhost_includes --all-users  

Add a listener (WebAdmin console > Configuration > Listeners > Add).

Make sure you click Yes under the Secure setting. (The other settings should be customized to listen to the correct IP and port for the virtual hosts this listener will be mapping to.)

Open up the listener again (View/Edit).

Under the SSL tab, enter the paths and locations for your certificates and key files.

To set up OCSP stapling, you must set Enable OCSP Stapling to Yes. It is also better to put the address of your OCSP responder in the OCSP Responder field (though the server may be able to find it in your CA certificate). Check with your CA for your OCSP responder's address.

Click the Apply Changes link to execute a graceful restart and apply your changes.

Check in $SERVER_ROOT/temp/ocspcache/. If a file has been created there, then your OCSP stapling is working. If not, check your error logs for what went wrong.

Use the openssl command:

openssl s_client -connect $Your_Domain:443 -status

If OCSP stapling is working, it will show ok. Then check OCSP Response Status: should be successful in OCSP Response Data section

1. Open browser with URL https://cryptoreport.rapidssl.com
2. key in your domain then check OCSP stapling status

OCSP response is cached for 1-day. If you change your SSL certificate provider and see a cached OCSP response for a domain, you can easily remove the cache files under ocsp cache folder.