For the sake of simplicity, the following acronyms will be used in this
Advanced Techniques workshop:
Key Distribution Center
Full qualified hostname
The following example will be used for the configuration:
KDC is available at: kdc.example.org
FQHN of the Tomcat server is: tomcat.example.org
Domain is called: EXAMPLE / EXAMPLE.ORG
Tomcat AD user login: tomcat_user
Tomcat AD user password: SECRET_PASSWORD
1. Preparations on the domain controller
An AD user account for the Tomcat service needs to be created with the
following activated options:
Password never expires
User can't change password
This account supports Kerberos AES 128 bit encryption
(The password is SECRET_PASSWORD in our example)
An SPN (Service Principal Name) needs to be created and assigned to the
Tomcat user account. This is case-sensitive. Make sure that an SPN
isn't already registered for the Tomcat user. The SPN is assigned to the
Tomcat user with the following commands:
setspn -A HTTP/tomcat.example.org tomcat_user
setspn -A HTTP/tomcat tomcat_user
Using the command setspn -L tomcat_user you can check whether
an SPN has already been registered for the user.
If an SPN is already registered for the user, you can use the following
command to remove the entries:
The Tomcat service must register with the KDC (Active Directory Server)
when it starts. That's why a
user with the corresponding password
was created on the AD. So that this information is available to the Tomcat
service on startup, a keytab file with the required login data needs to be
generated. We recommend using the Java Tool ktab.exe to generate this.
This is included in the Windows JRE and therefore already installed on a client
with a Portal Manager installation, for example. The ktab.exe must then be
executed on the computer of the domain because information is retrieved from
the KDC during the execution. The generated file will be copied to the
Tomcat server later. Carry out the following steps to generate the file:
Open the command prompt and go to the bin directory of the Intrexx JRE:
Generate the keytab. tomcat_user and SECRET_PASSWORD, as well as the output path
of the file must, of course, be adjusted accordingly:
ktab.exe -a tomcat_user SECRET_PASSWORD -n 0 -k c:/PATH/TO/KEYTAB.FILE/tomcat.keytab
The file generated with this must then be copied to the Intrexx server
and protected accordingly as it contains login information
for the Tomcat user.
Here is a short explanation of each of the options:
-a adds SPN and password
-k states the keytab file to be written to
-n0 is required to set the keytab counter (KVNO) to 0
Ktpass.exe, which is already installed on AD servers, should not be
used for generating the keytab.
3. Installation on the Intrexx-side
3.1 Integrate Spnego library in Tomcat
The library is integrated automatically during a new installation of Intrexx
8; this point can be skipped in that case. If you have switched from an older
version to Intrexx 8 by installing to the existing directory, the corresponding
module must potentially be integrated manually. The corresponding library
can be found in
installation directory /lib
and is called spnego-r7.jar. So that Tomcat uses this as well, an entry needs
to be added to tomcat.wcf
im installation directory /cfg
The numbering XX must be unique in accordance with the existing classpath
3.2. Adjust spnego.login.conf and spnego.krb5.conf
The keytab was created and copied to the Intrexx server.
It will now be integrated in the spnego.login which will then in turn be
integrated in the web.xml.
For the sake of simplicity, we will store all of the files used by Tomcat
in the example path C:/PATH/TO/KEYTAB.FILE/ in the following. The keytab
tomcat.keytab should already be stored there.
We will store spnego.login.conf and spnego.krb5.conf there as well.
Examples of both files can be found in the
installation directory /samples/tomcat_kerberosauth/doc.
This can be copied to the path named above and then adjusted accordingly.
The two key entries in the spnego.login.conf are the path to the
keytab (i.e. the keyTab= entry) and the Tomcat AD user (the principal= entry).
The spnego.login.conf looks like this with the settings used in our example:
In the spnego.krb5.conf, the Kerberos realm entries must be adjusted
accordingly. From experience, this correspond to the domain entry.
The entries must be written in block capitals. The spnego.krb5.conf
will then look like this:
The files created in the previous step (spnego.login.conf and spnego.krb5.conf)
will at last be integrated in the web.xml. The web.xml can be found in the
portal directory /external/htmlroot/WEB-INF/.
By default, this contains an commented out entry for the spnego filter.
The comments should be removed here and the path to both of the files should be
adjusted accordingly so that the respective section looks like this:
After restarting the Tomcat service,
Tomcat should now authenticate against the KDC. You can check whether this was
successful in the tomcat_startup.log.
INFO | jvm 1 | 2016/05/18 15:28:28 | Debug is true storeKey true useTicketCache false useKeyTab true doNotPrompt false ticketCache is null isInitiator true KeyTab is ///C:/PATH/TO/KEYTAB.FILE/tomcat.keytab refreshKrb5Config is false principal is tomcat_user tryFirstPass is false useFirstPass is false storePass is false clearPass is false
INFO | jvm 1 | 2016/05/18 15:28:28 | principal is tomcat_user@EXAMPLE.ORG
INFO | jvm 1 | 2016/05/18 15:28:28 | Will use keytab
INFO | jvm 1 | 2016/05/18 15:28:28 | Commit Succeeded
3.5. Entries in LucAuth.cfg and om.cfg
In the following, the setup on the Intrexx-side will be described.
So that Intrexx, or rather the respective portal, uses the Kerberos module
for the authentication, a corresponding login provider must be added in the
LucyAuth.cfg; this in turn needs to be integrated in the om.cfg for the
respective service. Both files can be found in the
portal directory /internal/cfg.
For the entry in the LucyAuth.cfg, a LucyAuth.cfg with example entries can be
found in the
installation directory /samples/tomcat-kerberosauth/doc/.
In general, the entry TomcatKerberosAuth2 should be sufficient.
If the UserPrincipalName is different from the
sAMAccountName, then the entry TomcatKerberosAuth3 is recommended.
In the Active Directory, the aSAMAccount entry for the user Henry Miller
is PRE2000EXAMPLE\henrym. The UserPrincipalName of the same user is
firstname.lastname@example.org. The user import was performed with the
Active Directory NTLM. If the pre2000 domain name differs from the
UserPrincipal domain name, the pre2000 domain can be transferred explicitly
with the following entry in LucyAuth.cfg:
If multiple domains are in use, these can be configured in more depth
using Groovy scripting. In this case, the entry TomcatKerberosAuth4 provides
the ability to refer to a Groovy script and perform additional configurations
there. So that the changes take effect, the
portal service needs to be restarted.
4. Browser-side adjustments
4.1. Internet Explorer
The Tomcat server needs to be added under Internet options / Security / Sites
- in our example as tomcat.example.org.
Enter about:config in the address bar. The Tomcat server needs to be added
After the portal and Tomcat service have been restarted, you can test the
authentication with any user from the AD. After logging on to the Windows
system, this user - provided they are a user from the domain - should
receive a Kerberos ticket; this can be checked using the following
The portal can now be opened in the browser. If the login is not successful,
looking at the portal.log is helpful; this can be found in the
portal directory /log.
If the login procedure fails, the corresponding login data is logged here.
If the login information there doesn't match the login data of the
corresponding Intrexx user, then this needs to be taken into account
during the user replication by using a different profile or by adjusting
the used replication profile accordingly.
Whether Kerberos Authentication can be implemented while using
Tomcat on the target system, is heavily dependent on the
system environment (Active Directory / Network).