CASifying Tomcat Manager

How to CASify Tomcat Manager

This page provides a how-to in CASifying the Tomcat Manager web application.

Produced using Tomcat 5.0.28, but this approach should apply to other versions of Tomcat.

CASifying Standalone Tomcat

This section describes the (easier) case of CASifying Tomcat Manager where CATALINA_HOME is CATALINA_BASE.

Hacking the web.xml

Locate the web.xml descriptor for the manager web application

It will be in the /server/webapps/manager/WEB-INF directory of your Tomcat. For instance, mine's at I:\Tomcat\jakarta-tomcat-5.0.28\server\webapps\manager\WEB-INF .

Remove the container authentication and security stuff

We aren't going to use the Tomcat container authentication and servlet container security. We're going to replace it with CAS and a simple AuthZ filter.

Here's the stuff you don't need:

Remove this from the web.xml

  <!-- Define reference to the user database for looking up roles -->
  <resource-env-ref>
    <description>
      Link to the UserDatabase instance from which we request lists of
      defined role names.  Typically, this will be connected to the global
      user database with a ResourceLink element in server.xml or the context
      configuration file for the Manager web application.
    </description>
    <resource-env-ref-name>users</resource-env-ref-name>
    <resource-env-ref-type>
      org.apache.catalina.UserDatabase
    </resource-env-ref-type>
  </resource-env-ref>

  <!-- Define a Security Constraint on this Application -->
  <security-constraint>
    <web-resource-collection>
      <web-resource-name>HTMLManger and Manager command</web-resource-name>
      <url-pattern>/jmxproxy/*</url-pattern>
      <url-pattern>/html/*</url-pattern>
      <url-pattern>/list</url-pattern>
      <url-pattern>/sessions</url-pattern>
      <url-pattern>/start</url-pattern>
      <url-pattern>/stop</url-pattern>
      <url-pattern>/install</url-pattern>
      <url-pattern>/remove</url-pattern>
      <url-pattern>/deploy</url-pattern>
      <url-pattern>/undeploy</url-pattern>
      <url-pattern>/reload</url-pattern>
      <url-pattern>/save</url-pattern>
      <url-pattern>/serverinfo</url-pattern>
      <url-pattern>/status/*</url-pattern>
      <url-pattern>/roles</url-pattern>
      <url-pattern>/resources</url-pattern>
    </web-resource-collection>
    <auth-constraint>
       <!-- NOTE:  This role is not present in the default users file -->
       <role-name>manager</role-name>
    </auth-constraint>
  </security-constraint>

  <!-- Define the Login Configuration for this Application -->
  <login-config>
    <auth-method>BASIC</auth-method>
    <realm-name>Tomcat Manager Application</realm-name>
  </login-config>

  <!-- Security roles referenced by this web application -->
  <security-role>
    <description>
      The role that is required to log in to the Manager Application
    </description>
    <role-name>manager</role-name>
  </security-role>

After removing all that, you should be left with this:

Bare web.xml

<?xml version="1.0" encoding="ISO-8859-1"?>

<!DOCTYPE web-app
    PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
    "http://java.sun.com/dtd/web-app_2_3.dtd">

<web-app>

  <display-name>Tomcat Manager Application</display-name>
  <description>
    A scriptable management web application for the Tomcat Web Server;
	Manager lets you view, load/unload/etc particular web applications.
  </description>

  <!-- Define the Manager Servlet
       Change servlet-class to: org.apache.catalina.servlets.HTMLManagerServlet
       to get a Servlet with a more intuitive HTML interface, don't change if you
       have software that is expected to parse the output from ManagerServlet
       since they're not compatible.
   -->
  <servlet>
    <servlet-name>Manager</servlet-name>
    <servlet-class>org.apache.catalina.manager.ManagerServlet</servlet-class>
    <init-param>
      <param-name>debug</param-name>
      <param-value>2</param-value>
    </init-param>
  </servlet>
  <servlet>
    <servlet-name>HTMLManager</servlet-name>
    <servlet-class>org.apache.catalina.manager.HTMLManagerServlet</servlet-class>
    <init-param>
      <param-name>debug</param-name>
      <param-value>2</param-value>
    </init-param>
  </servlet>
  <servlet>
    <servlet-name>Status</servlet-name>
    <servlet-class>org.apache.catalina.manager.StatusManagerServlet</servlet-class>
    <init-param>
      <param-name>debug</param-name>
      <param-value>0</param-value>
    </init-param>
  </servlet>

  <servlet>
    <servlet-name>JMXProxy</servlet-name>
    <servlet-class>org.apache.catalina.manager.JMXProxyServlet</servlet-class>
  </servlet>

  <!-- Define the Manager Servlet Mapping -->
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/list</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/sessions</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/start</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/stop</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/install</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/remove</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/deploy</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/undeploy</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/reload</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/save</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/serverinfo</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/roles</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/resources</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Status</servlet-name>
    <url-pattern>/status/*</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>JMXProxy</servlet-name>
      <url-pattern>/jmxproxy/*</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>HTMLManager</servlet-name>
    <url-pattern>/html/*</url-pattern>
  </servlet-mapping>

</web-app>

Add in CAS authentication

Now we have a bare, unprotected Manager. We need to add CAS authentication to it.

So we need to map the CASFilter to provide for authentication.

Add this to the web.xml (with appropriate URLs for your CAS server and the server name for the Manager you are CASifying).

Declaring the CASFilter

  <filter>
    <filter-name>CASFilter</filter-name>
	<filter-class>edu.yale.its.tp.cas.client.filter.CASFilter</filter-class>
	<init-param>
        <param-name>edu.yale.its.tp.cas.client.filter.loginUrl</param-name>
		<param-value>https://secure.its.yale.edu/cas/login</param-value>
	</init-param>
	<init-param>
	    <param-name>edu.yale.its.tp.cas.client.filter.validateUrl</param-name>
		<param-value>https://secure.its.yale.edu/cas/serviceValidate</param-value>
	</init-param>
	<init-param>
	    <param-name>edu.yale.its.tp.cas.client.filter.serverName</param-name>
		<param-value>hkg2.cis.yale.edu:8080</param-value>
	</init-param>
  </filter>

  <filter-mapping>
      <filter-name>CASFilter</filter-name>
	  <url-pattern>/*</url-pattern>
  </filter-mapping>

Require authorization

We haven't added much, if any, security yet, because anyone who can CAS authenticate can now access the Manager. We need to add an authorization layer. For this we'll use the very simple Filter that comes with the Java CAS client to declare NetIDs authorized to access the Manager.

The SimpleCASAuthorization filter takes a whitespace-delimitted list of authorized usernames and asserts that the CAS authenticated username is one of these authorized users, throwing an exception when this is not the case. Here, for example, we authorize both user "awp9" and user "jdb53" to access Tomcat manager.

Add this filter declaration:

Declaring the Simple CAS Authorization filter

  <filter>
    <filter-name>Authz Filter</filter-name>
	<filter-class>edu.yale.its.tp.cas.client.filter.SimpleCASAuthorizationFilter</filter-class>
	<init-param>
        <param-name>edu.yale.its.tp.cas.client.filter.authorizedUsers</param-name>
		<param-value>awp9 jdb53</param-value>
	</init-param>
  </filter>

And add this filter mapping:

Mapping the simple CAS Authorization filter

  <filter-mapping>
      <filter-name>Authz Filter</filter-name>
	  <url-pattern>/*</url-pattern>
  </filter-mapping>

The final web.xml should look like this:

web.xml for a CASified Manager

<?xml version="1.0" encoding="ISO-8859-1"?>

<!DOCTYPE web-app
    PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
    "http://java.sun.com/dtd/web-app_2_3.dtd">

<web-app>

  <display-name>Tomcat Manager Application</display-name>
  <description>
    A scriptable management web application for the Tomcat Web Server;
	Manager lets you view, load/unload/etc particular web applications.
  </description>


  <filter>
    <filter-name>CASFilter</filter-name>
	<filter-class>edu.yale.its.tp.cas.client.filter.CASFilter</filter-class>
	<init-param>
        <param-name>edu.yale.its.tp.cas.client.filter.loginUrl</param-name>
		<param-value>https://secure.its.yale.edu/cas/login</param-value>
	</init-param>
	<init-param>
	    <param-name>edu.yale.its.tp.cas.client.filter.validateUrl</param-name>
		<param-value>https://secure.its.yale.edu/cas/serviceValidate</param-value>
	</init-param>
	<init-param>
	    <param-name>edu.yale.its.tp.cas.client.filter.serverName</param-name>
		<param-value>hkg2.cis.yale.edu:8080</param-value>
	</init-param>
  </filter>

  <filter>
    <filter-name>Authz Filter</filter-name>
	<filter-class>edu.yale.its.tp.cas.client.filter.SimpleCASAuthorizationFilter</filter-class>
	<init-param>
        <param-name>edu.yale.its.tp.cas.client.filter.authorizedUsers</param-name>
		<param-value>awp9 jdb53</param-value>
	</init-param>
  </filter>
  <filter-mapping>
      <filter-name>CASFilter</filter-name>
	  <url-pattern>/*</url-pattern>
  </filter-mapping>

  <filter-mapping>
      <filter-name>Authz Filter</filter-name>
	  <url-pattern>/*</url-pattern>
  </filter-mapping>

  <!-- Define the Manager Servlet
       Change servlet-class to: org.apache.catalina.servlets.HTMLManagerServlet
       to get a Servlet with a more intuitive HTML interface, don't change if you
       have software that is expected to parse the output from ManagerServlet
       since they're not compatible.
   -->
  <servlet>
    <servlet-name>Manager</servlet-name>
    <servlet-class>org.apache.catalina.manager.ManagerServlet</servlet-class>
    <init-param>
      <param-name>debug</param-name>
      <param-value>2</param-value>
    </init-param>
  </servlet>
  <servlet>
    <servlet-name>HTMLManager</servlet-name>
    <servlet-class>org.apache.catalina.manager.HTMLManagerServlet</servlet-class>
    <init-param>
      <param-name>debug</param-name>
      <param-value>2</param-value>
    </init-param>
  </servlet>
  <servlet>
    <servlet-name>Status</servlet-name>
    <servlet-class>org.apache.catalina.manager.StatusManagerServlet</servlet-class>
    <init-param>
      <param-name>debug</param-name>
      <param-value>0</param-value>
    </init-param>
  </servlet>

  <servlet>
    <servlet-name>JMXProxy</servlet-name>
    <servlet-class>org.apache.catalina.manager.JMXProxyServlet</servlet-class>
  </servlet>

  <!-- Define the Manager Servlet Mapping -->
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/list</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/sessions</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/start</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/stop</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/install</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/remove</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/deploy</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/undeploy</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/reload</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/save</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/serverinfo</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/roles</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Manager</servlet-name>
      <url-pattern>/resources</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>Status</servlet-name>
    <url-pattern>/status/*</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>JMXProxy</servlet-name>
      <url-pattern>/jmxproxy/*</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>HTMLManager</servlet-name>
    <url-pattern>/html/*</url-pattern>
  </servlet-mapping>

</web-app>

Adding the required jar file

Install the Java CAS client .jar file (version 2.1.0 or later, current as of this writing is 2.1.1), into the lib directory associated with the manager web application. For me this was I:\Tomcat\jakarta-tomcat-5.0.28\server\webapps\manager\WEB-INF\lib .

CASifying multiple Tomcats

Any takers for documenting how to CASify Tomcat Manager for an installation of several CATALINA_BASEs sharing a single CATALINA_HOME?

Edit