Securing a Tomcat Webapp – Part 2

If you wish to password protect your webapp with an Apache .htaccess type authentication model, you require two configuration steps. The first within your WEB-INF/web.xml, add the following replacing rolename appropiately.

<security-constraint>
    <web-resource-collection>
      <web-resource-name>All Pages</web-resource-name>
        <url-pattern>*.htm</url-pattern>
        <url-pattern>*.html</url-pattern>
   </web-resource-collection>
    <auth-constraint>
       <role-name>rolename</role-name>
    </auth-constraint>
  </security-constraint>

  <!-- Define the Login Configuration for this Application -->
  <login-config>
    <auth-method>BASIC</auth-method>
    <realm-name>Test 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 Application
    </description>
    <role-name>rolename</role-name>
  </security-role>

Second, within the tomcat $CATALINA_HOME/conf/server.xml, you need to define the Realm used within the appropiate host’s definition.

<Realm className="org.apache.catalina.realm.UserDatabaseRealm" debug="0" resourceName="UserDatabase"/>

This Realm connects with a known resource, which I define with the $CATALINA_HOME/conf/server.xml definition.

<Resource name="UserDatabase" auth="Container"
          type="org.apache.catalina.UserDatabase"
          description="User database that can be updated and saved">
</Resource>
<ResourceParams name="UserDatabase">
    <parameter>
        <name>factory</name>
        <value>org.apache.catalina.users.MemoryUserDatabaseFactory</value>
    </parameter>
    <parameter>
        <name>pathname</name>
        <value>conf/custom/users.xml</value>
    </parameter>
</ResourceParams>

NOTE: The use of MemoryRealm has limited uses. Tomcat provides 5 different Realm implementations including JDBC, DataSource,JINDI, Memory and JAAS.

And of course you need to define your user authentication within the appropiately defined users file. In this case conf/custom/users.xml

Tagged with: General Java Tomcat

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