JAAS Authentication Handler
Briefly, JAAS is a standard API provided by Java 1.4 and higher which provides PAM-like authentication and authorization. An external file is used to configure JAAS. Using JAAS with CAS allows modification of the authentication process without having to rebuild and redeploy CAS, and allows for PAM-style multi-module "stacked" authentication.
Links
Core Classes
JaasAuthenticationHandler
The JaasAuthenticationHandler is a hook into the Java Authentication and Authorization Service and delegates all authentication to the underlying runtime and its configured JAAS file. Therefore it only has one property:
- realm - the realm within the JAAS configuration file we are going to use. Defaults to CAS.
Configuration
Like other handlers, the JAAS Authentication Handler is simply configured in the deployerConfigContext.xml. Within the AuthenticationManager's "authenticationHandlers" property, place the following configuration (replacing the example Test handler):
<bean class="org.jasig.cas.authentication.handler.support.JaasAuthenticationHandler" />
Example jaas.conf File
Below, you'll find an example jaas.conf file which would contain your JAAS configuration information.
The path to the JAAS Configuration file is specified for this JVM as a system property, i.e. -Djava.security.krb5.conf=/etc/krb5.conf, or a default can be specified for an entire Java Runtime Environment by changing the
{jre-home}/lib/security/java.security properties file to add a "Default login configuration file" under the property "login.config.url.1=file:..." (find the comment example in the current file).
/** * Login Configuration for JAAS. First try Kerberos, then LDAP, then AD * Note that a valid krb5.conf must be supplied to the JVM for Kerberos auth * -Djava.security.krb5.conf=/etc/krb5.conf */ CAS { com.ibm.security.auth.module.Krb5LoginModule sufficient debug=FALSE; edu.uconn.netid.jaas.LDAPLoginModule sufficient java.naming.provider.url="ldap://ldap.my.org:389/dc=my,dc=org" java.naming.security.principal="uid=cas,dc=my,dc=org" java.naming.security.credentials="password" Attribute="uid" startTLS="true"; edu.uconn.netid.jaas.LDAPLoginModule sufficient java.naming.provider.url="ldaps://ad.my.org:636/dc=ad,dc=my,dc=org" java.naming.security.principal="cas@ad.my.org" java.naming.security.credentials="password" Attribute="sAMAccountName"; };
If you enable the Krb5LoginModule and authenticate the userid and password against a Kerberos KDC, then Java must be told the name of the Kerberos Realm and the network name of the KDC. Again, this can be done with system properties (java.security.krb5.realm and java.security.krb5.kdc) or by copying a Unix krb5.conf file into the {jre-home}/lib/security directory. Note that SPEGNO also uses Kerberos and sets the same system properties. So if you are planning to use both JAAS and SPEGNO with Kerberos, read about SPEGNO configuration when planning JAAS.