Creating SSL Certificates with Multiple Host Names

Creating an SSL Certificate with Multiple Hostnames

There's another article on creating wildcard certificates in apache (and here on IIS), but we've not discussed the possibility of having a single certificate answer to several hostnames (DNS cnames, and http host headers). This uses an SSL feature called SubjectAlternativeName (or SAN, for short). Not only is this possible, but it's reasonably easy. We'll talk about generating the certificates using openssl on linux, but openssl is available for Windows, also, and the procedure is the same. Note that Windows' selfssl utility doesn't provide the ability to generate a certificate request file with SANs, so if you want to use this on Windows, you'll need to use openssl or another ssl utility.

WebLogic Case Sensitivity

Prior to v9.0, Weblogic was case-insensitive in Windows, but starting with v9, the default is, like Apache, to be case sensitive. A web search on changing that behavior isn't very helpful, and the setting is buried a bit, so I thought I'd post the instructions on changing that setting. The first step is to run the weblogic admin console. The default URL, once that has been started, is to browse to http://servername:9999/console. You'll be prompted for the username/password that you configured when installing weblogic. Once there, click on Domain-> Security-> Advanced. There you will see a "Web App Files Case Insensitive:" setting. By default, this is set to "false". Change it to "os", click on save. Once it's been saved, the changes have to be Activated. Click on the green Activate Changes button on the left-hand side of the screen.

You'll have to reboot the admin console, as well as your standard weblogic web services, for this change to take effect.

Using SSL with a Wildcard Certificate on Multiple Apache Sites

It is possible to set up multiple virtual SSL-encrypted hosts (sites) in apache, but did you know it's possible for them all to use port 443 and the same IP address? Wildcard certificates help make it happen.
Setting up SSL virtual hosts in linux (specifically RHEL and CentOS, but the steps are similar in other distros) isn't hard, and--to correct a common misperception--it is possible to have multiple SSL virtual hosts running under apache using host headers. To be clear: you don't have to use separate IP addresses or different port numbers in order to have multiple SSL sites under apache.
In short, the process involves creating multiple SSL virtual hosts, each with its own host header (ServerName in apache parlance), and adding the same wildcard SSL certificate to each of the sites. There are a variety of ways to create a certificate, and you can see many of them discussed with a simple Google search. In our case, we'll use genkey from crypto-utils. Feel free to use any utility you'd like

Multiple SSL Sites on a Single IIS Server Using Host Headers

Wildcard SSL certificates can allow you to publish multiple IIS web sites--all using SSL on port 443--that are accessible by host headers. That is, if you're running on IIS 6 or above.


So you read about these things, wildcard certificates, but mostly you read about how to buy them. It is possible (and easy) to create one for yourself, however, so long as you don't mind it not being trusted by folks' browsers. There are some really good uses for these, not least in a test environment in which you don't care about the trust. 
Production environments need them, too, sometimes, such as when you're using a network appliance like a Netscaler or F5 load balancer. Those devices allow you to point multiple URLs (cnames, really) to a single (or multiple) server(s). Very handy.
In our case, we have several web sites that we'd like to secure using SSL. Problem is: they're all on a single server. There are several options for dealing with such a case: assign multiple IP addresses to the server, use different SSL ports for each IIS site, or (definitely the coolest option) use a wildcard certificate on the server to allow IIS to decipher the http host header. This option, by the way, is a new feature with IIS 6, so if there's anyone out there still using IIS v5, this is another reason to upgrade.