How to Integrate PKI Certs or CAC Cards with ALI

In his 1947 speech to the House of Commons, Winston Churchill quipped, “It has been said that democracy is the worst form of government except all those other forms that have been tried.”

I’m not nearly as pithy as Sir Winston (nor as portly — at least not yet), but yet I feel the same way about passwords being used to protect web sites or other enterprise systems. In many ways, they’re the worst form of security out there except for everything else that’s been tried. Part of this has something to do with what I’ve coined Bucchere’s Axiom of Strong Passwords, which is a derivative of Murphy’s Law (which states that whatever can go wrong will). It goes something like this: the stronger a password is, the easier it is to hack. Why? Because if you force users into using a strong password, they’re more likely to write it down. And writing a password down defeats its purpose entirely.

The bottom line: passwords suck. But they’ve become the de-facto standard because they’re easier and cheaper than everything else we’ve tried, including PKI certs, biometrics (e.g. fingerprints, retina-scans), CAC cards, RSA secure IDs, etc. (Even for a cert-based authentication scheme, you still need a key to generate your cert, which is essentially just a glorified password.)

Just because passwords are the de-facto standard for authentication does not mean that we should quit trying to use other, ostensibly better forms of security, especially if 1) you’re protecting particularly sensitive data, 2) you’re open to the internet and 3) you have the resources (e.g. $$$) to invest in more robust forms of security. And I’m not talking about just buying an SSL cert from Verisign and continuing to have your users write down their passwords on post-it notes attached to their monitors. (Note to self: remove the post it note on your monitor with your password on it when you get back to the office.) I’m talking about using some sort of “soft” cert (e.g. PKI) or “hard” cert (e.g. CAC) to protect your system and your data.

Now if your system is ALI (formerly known as Plumtree Foundation or Plumtree Portal), you’re in luck, because the eggheads at what was once known as Plumtree have made this particularly easy to do. In fact, the hardest part is just getting the user’s identity out of the cert (see below the code snippet for some suggestions). Once you’ve done that, just drop a class into a jar that implements the ISSOProvider interface. (For those of you running on Windows, please don’t ask me to “port” this to C# — just take the Java code, drop it into Visual Studio.NET and then fix the syntax errors.)

But wait, SSO stands for “Single Sign On,” right? And what you’re really doing here is passing credentials from a cert to Plumtree and that has little or nothing to do with SSO. That’s a true statement. The subtlety here is that ISSOProvider, while it contains the letters SSO in its name, can be used for pretty much any form of authentication, whether you are using an SSO product or not.

package com.bdgportal.alui.auth;

import com.plumtree.openfoundation.util.*;
import com.plumtree.openfoundation.web.*;
import com.plumtree.portaluiinfrastructure.sso.*;

public class CertIntegration implements ISSOIntegration {
   private XPHashtable settings;
   public CertIntegration() {
   public boolean Initialize(XPHashtable settings) {
     this.settings = settings;       
     //String exampleSetting = ((XPArrayList)settings.GetElement("SettingName")).GetElement(0);

   public String GetSSOProductName() {
     return "My Favorite Cert Integration";

    * Gets the username from the cert and returns it to Plumtree. This will fail if the username
    * does not have a matching account in Plumtree. This can be a Plumtree database user or a user
    * imported from an authentication source, in which case you need to include the auth source
    * prefix in the username, e.g. "MyAuthSource/cbucchere"
    * @param request The wrapped HttpServletRequest from the web container.
    * @return The object passed back to Plumtree for authentication with the portal.
   public SSOLoginInfo GetLoginInfo(IXPRequest request) {
     String userName = ((XPRequest)request).GetUnderlyingObject().getUserPrincipal().getName();
     return new SSOLoginInfo(userName);

   public String[] GetSecureCookies() {
     return null;

   public String[] GetSecureHeaders() {
     return null;

   public boolean OnLogout(IXPResponse response, String returnURI) {
     return false;

The hardest part about all this, as I said above, is getting the user name out of the PLI cert/CAC card/retina scan/etc. In the example above, I made MANY assumptions. First, I assumed that your portal is running on Weblogic, which understands and correctly implements Principal, which is a Java Servlet’s way of knowing who’s using it. Weblogic lets you plug custom implementations of the Principal class into its security infrastructure. All you need to do is extend and then walk through a bunch of magical configuration steps to enable it.

Speaking of magical configuration, I neglected to mention that there are two small configuration steps that you need to perform in order to get your shiny new ISSOIntegration working in ALI. In portalconfig.xml, you need to set the value of SSOVendor setting to 100 (or greater) and then set the CustomSSOClass to the fully qualified name of the class you wrote that implements ISSOIntegration. For our Java example above, that would be com.bdgportal.alui.auth.CertIntegration and for .NET, it would the the name of your C# class.

Speaking of .NET . . . as many of you know, it is an entirely different animal with its own way of provisioning security to web applications (e.g. System.Web.Security).

Regardless of your platform, you need to get the user name out of whatever authentication method you’re using. Once you’ve accomplished that, just drop the code above into your project and replace the getUserPricipal().getName() with whatever mechanism you can find for getting your users’ names.

Assuming you trust your authentication mechanism to return the appropriate user name, you’ll have users getting logged into the portal via pretty much however you would like — CAC, PKI, biometrics, etc.

If only implementing a democracy were this easy . . . .


Comments are listed in date ascending order (oldest first)

  • This is wonderful article. How ever I’ve researched for a long time but still can not figure out what to do with Bea Weblogic to use Costom Identify Assertion. I wish this artical to have link to the document of how to “do the magical configuration steps”.

    Posted by: minh.tran on January 9, 2007 at 9:04 AM

  • This article was intended to be application server independent, but if you’re using BEA WebLogic, there’s a great article on how to set up custom identity providers which should work with this ALUI SSO solution.

    Posted by: bucchere on January 10, 2007 at 6:44 PM

  • NOTE: 1. the user’s password in the portal must be empty string. 2. jar should be put in portal.war and lib/java.

    Posted by: luotuoci on April 28, 2007 at 8:31 PM

Leave a Reply