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key

Windows CA template – web server and private key export

Creating a web server certificate request is very easy when using a Windows CA server. There is one disadvantage. The requested certificate is directly stored in the user store (by default) or the local computer store, if specified during the request. The disadvantage is that you cannot export the requested certificate including the private keys. During the request the option to Mark keys as exportable is grayed out.

There is a way to mark the keys as exportable when using a Windows CA server. You need to create a new Web Server Certificate template. You can use the existing Web Server Certificate Template as default and copy the current settings. To do so, you just:

  • run certtmpl.msc, which will open the Certificate Template snap-in;
  • click the Web Server certificate template;
  • choose Action – Duplicate Template;
  • configure a unique template name;
  • choose the tab Request Handling;
  • enable the option Allow private key to be exported;

That is all you need to do. You can now request a new certificate with the newly create certificate template. After the certificate is issued and installed on the user or local computer store, you can export the certificate including the private key.

Duplicate certificate template

Allow private key to be exported

Change password through LDAPS on ISA server

Today I received the question about allowing users to changes his/her password through webmail, whereby webmail is published via an ISA server 2006 reverse proxy. This is possible, but it requires the configuration of LDAPS to authenticate users.

I started by configuring a Certificate Authority (CA) on a member server in the domain. During the installation of CA a root certificate is generated. You need to export this root certificate with private key. Next I imported the certificate on the reverse proxy server, but didn’t mark the private key as exportable. So the root certificate cannot be exported from the reverse proxy server with its private key in the future. I checked if binding to the Active Directory is possible by using the tool ldp.exe.

The last part is configuring LDAP Validation in ISA. Go to Configuration –> General –> Specify RADIUS and LDAP Servers. First you need to add a LDAP server set, like shown in the following picture.

Important when configuring the LDAP server set is the usage of the FQDN as LDAP server hostname. This FQDN should be exactly the same compared to the FQDN mentioned in the imported root certificate.

The last step is configuring the LDAP server mapping, which is also shown below.

Because I don’t want to add a domain name during the login procedure on the OWA login page, like DOMAIN\USER, I use the Login Expression wildcard character * and link that to the configured LDAP server set. Now you can login with just username and password, instead of domain\username and password.

Next I configure a OWA Publishing policy like always, but on the Listener I use LDAP as authentication mechanism. On the Listener Forms tab you can enable or disable the options:

  • Allow users to change their passwords;
  • Remind users that their passwords will expire in this number of days;

These options add some extra option to the OWA login page. Another step to configure is the allowed users. In most environments I use the group Domain Users as allowed OWA group, because mostly all users are allowed to use OWA, else you need to configure a separate user group in Active Directory. On the Users tab you remove the All Authenticated Users and click Add. You need to define a new user group, like shown below.

User Group

This means that if you are member of the group Domain Users, you are allowed to use OWA.

The last step is configuring the public path. When logged in to OWA, you have the option to change your password through the options page. To use this feature, you need to added another path to the Path configuration in the reverse proxy server. The path, which should be added, is /iisadmpwd/*, where the External Path is the same as the Internal Path.

Over at isaserver.org, Thomas Shinder wrote a great post about using LDAPS with OWA and multiple domains. The article is called LDAP Pre-Authentication with ISA 2006 Firewalls: Using LDAP to Pre-Authenticate OWA Access.