Tomcat LDAP authentication

1. allow SSL connections, adding the LDAP server root certificate to the cacerts
   file of the Tomcat JRE. It can be found in your $JAVA_HOME/lib/security directory.
   Use the java keytool command to add the certs:
  
   List the existing certificates:
   keytool -list -v -keystore cacert
  
   Import certificate:
   keytool -importcert -alias HELLO -file <path>/trustedrootcert.cer -keystore <path>/lib/security/cacerts
   Password is: changeit 

2. verify the configuration in <CATALINA_BASE>/conf/Catalina/localhost/<webapp>.xml:

    <Realm className="org.apache.catalina.realm.JNDIRealm"

        connectionURL="ldaps://ldap.company.org:636"
        connectionName="cn=user,ou=serviceusers,ou=services,o=ORG"
        connectionPassword="pwd"
       
        userBase="o=ORG"
        userSubtree="true"
        userSearch="(cn={0})"

        roleBase="ou=Functions,ou=GROUPS,o=ORG"
        roleName="cn"
        roleSearch="(member={0})"
    />

3. verify the configuration in web.xml:

    <security-constraint>
        <display-name>LDAP security constraint</display-name>
        <web-resource-collection>
            <web-resource-name>Protected Area</web-resource-name>
            <url-pattern>/*</url-pattern>
        </web-resource-collection>
        <auth-constraint>
            <role-name>MyRequiredGroup</role-name>
        </auth-constraint>
    </security-constraint>

    <login-config>
        <auth-method>BASIC</auth-method>
        <realm-name>Tomcat auth</realm-name>
    </login-config>

    <security-role>
        <role-name>MyRequiredGroup</role-name>
    </security-role>