CASifying OpenCms
Requirements
1. OpenCms is authenticated by CAS + LDAP.
2. OpenCms is authorized by CAS + LDAP.
3. Support OpenCms OU.
4. CAS will search LDAP for groups and roles when validating, not authenticating.
5. Validation URI can be customised, not /serviceValidate only.
6. Easy to extend the module to support CAS + DATABASE.
Environments
Tested in Fedora 10, OpenJDK 1.6.0, Tomcat 5.5.27, OpenCms7.0.5, CAS3.3.1, OpenLDAP 2.4.12.
Login Procedure
Module Parameters
 Module parameters for authentication handler:
AuthenticationHandler: cn.langhua.opencms.ldap.cas.CmsCasAuthenticationHandler AutoUserRoleName: not required. If you want the user can login OpenCms workplace by default, this parameter should be RoleWorkplaceUsers. CasUrl: not required, default is https://localhost:8443/cas. CasLoginUri: not required, the uri to CAS login, default is /login. CasValidateUri: not required, the uri to CAS validate, default is /serviceValidate. CasLenientURL: not required, if set, this url will be used to validate CAS ticket, default is null. CasLogoutUri: not required, default is /logout.
 Module parameters for authorization handler:
AuthenticationHandler: cn.langhua.opencms.ldap.cas.CmsCasAuthorizationHandler GroupSearchDN: required, the group dn to resolve OpenCms OU. If not set, will use BaseDN. RoleSearchDN: required, the role dn to resolve OpenCms role. If not set, will use BaseDN. BaseDN: not required. AutoUserRoleName: not required. If you want the user can login OpenCms workplace by default, this parameter should be RoleWorkplaceUsers. CasUrl: not required, default is https://localhost:8443/cas. CasLoginUri: not required, the uri to CAS login, default is /login. CasValidateUri: not required, the uri to CAS validate, default is /serviceValidate. CasLenientURL: not required, if set, this url will be used to validate CAS ticket, default is null. CasLogoutUri: not required, default is /logout.
Add a new validate servlet to CAS
Here I use /authzValidate as the new validate servlet uri for an example.
1. Add /authzValidate in $(cas_server)/WEB-INF/web.xml
<!-- start service validate extensions --> <servlet-mapping> <servlet-name>cas</servlet-name> <url-pattern>/authzValidate</url-pattern> </servlet-mapping> <!-- end service validate extensions -->
2. Modify $(cas_server)/WEB-INF/cas-servlet.xml
... <!-- start service validate extensions --> <prop key="/authzValidate"> authzValidateController </prop> <!-- end service validate extensions --> ... <!-- start service validate extensions --> <bean id="authzValidateController" class="org.jasig.cas.web.ServiceValidateController" p:validationSpecificationClass="org.jasig.cas.validation.Cas20WithoutProxyingValidationSpecification" p:centralAuthenticationService-ref="centralAuthorizationService" p:proxyHandler-ref="proxy20Handler" p:argumentExtractor-ref="casArgumentExtractor" /> <!-- end service validate extensions -->
3. Modify $(cas_server)/WEB-INF/spring-configuration/applicationContext.xml
<!-- CentralAuthorizationService, please note, this is authz --> <bean id="centralAuthorizationService" class="cn.langhua.cas.LDAPAuthzCASImpl" p:ticketGrantingTicketExpirationPolicy-ref="grantingTicketExpirationPolicy" p:serviceTicketExpirationPolicy-ref="serviceTicketExpirationPolicy" p:authenticationManager-ref="authenticationManager" p:ticketGrantingTicketUniqueTicketIdGenerator-ref="ticketGrantingTicketUniqueIdGenerator" p:ticketRegistry-ref="ticketRegistry" p:servicesManager-ref="servicesManager" p:persistentIdGenerator-ref="persistentIdGenerator" p:uniqueTicketIdGeneratorsForService-ref="uniqueIdGeneratorsMap" p:attributeRepository-ref="attributeRepository" />
4.Modify $(cas_server)/WEB-INF/deployerConfigContext.xml
<bean id="attributeRepository" class="cn.langhua.cas.services.persondir.support.ldap.LdapPersonAttributeDaoExtension"> <property name="baseDN" value="o=langhua,c=cn" /> <!-- This query is used to find the entry for populating attributes. {0} will be replaced by the new Principal ID extracted from the ldap--> <property name="query" value="(uid:caseExactmatch:={0})" /> <property name="contextSource" ref="contextSource" /> <property name="groupSearchDN" value="ou=users,ou=opencms,ou=applications,o=langhua,c=cn" /> <property name="roleSearchDN" value="ou=roles,ou=opencms,ou=applications,o=langhua,c=cn" /> <property name="authorType" value="member" /> <property name="ldapAttributesToPortalAttributes"> <map> <!-- Mapping beetween LDAP entry's attributes (key) and Principal"s (value) --> <entry key="groups" value="groups" /> <entry key="roles" value="roles" /> <entry key="uid" value="uid" /> <entry value="title" key="title"/> <entry key="cn" value="Name"/> <entry key="sn" value="sn"/> </map> </property> </bean>
5. Modify $(cas_server)/WEB-INF/view/jsp/protocol/2.0/casServiceValidationSuccess.jsp
<%@ page session="false" pageEncoding="UTF-8" %><%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %><%@ taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn" %><cas:serviceResponse xmlns:cas='http://www.yale.edu/tp/cas'> <cas:authenticationSuccess> <cas:user>${fn:escapeXml(assertion.chainedAuthentications[fn:length(assertion.chainedAuthentications)-1].principal.id)}</cas:user> <c:if test="${fn:length(assertion.chainedAuthentications[fn:length(assertion.chainedAuthentications)-1].principal.attributes) > 0}"> <cas:attributes> <c:forEach var="attr" items="${assertion.chainedAuthentications[fn:length(assertion.chainedAuthentications)-1].principal.attributes}" varStatus="loopStatus" begin="0" end="${fn:length(assertion.chainedAuthentications[fn:length(assertion.chainedAuthentications)-1].principal.attributes)}" step="1"> <cas:attribute> <cas:name>${fn:escapeXml(attr.key)}</cas:name> <cas:value>${fn:escapeXml(attr.value)}</cas:value> </cas:attribute> </c:forEach> </cas:attributes> </c:if> <c:if test="${not empty pgtIou}"> <cas:proxyGrantingTicket>${pgtIou}</cas:proxyGrantingTicket> </c:if> <c:if test="${fn:length(assertion.chainedAuthentications) > 1}"> <cas:proxies> <c:forEach var="proxy" items="${assertion.chainedAuthentications}" varStatus="loopStatus" begin="0" end="${fn:length(assertion.chainedAuthentications)-2}" step="1"> <cas:proxy>${fn:escapeXml(proxy.principal.id)}</cas:proxy> </c:forEach> </cas:proxies> </c:if> </cas:authenticationSuccess> </cas:serviceResponse>
6. Sample of /authzValidate response
<cas:serviceResponse xmlns:cas='http://www.yale.edu/tp/cas'> <cas:authenticationSuccess> <cas:user>shijh</cas:user> <cas:attributes> <cas:attribute> <cas:name>uid</cas:name> <cas:value>shijh</cas:value> </cas:attribute> <cas:attribute> <cas:name>Name</cas:name> <cas:value>石京海</cas:value> </cas:attribute> <cas:attribute> <cas:name>sn</cas:name> <cas:value>石京海</cas:value> </cas:attribute> <cas:attribute> <cas:name>title</cas:name> <cas:value>manager</cas:value> </cas:attribute> <cas:attribute> <cas:name>roles</cas:name> <cas:value>cn=RoleRootAdmins,ou=opencms,ou=roles,ou=applications,o=langhua,c=cn</cas:value> </cas:attribute> <cas:attribute> <cas:name>distinguishedName</cas:name> <cas:value>uid=shijh,ou=beijing,o=langhua,c=cn</cas:value> </cas:attribute> <cas:attribute> <cas:name>groups</cas:name> <cas:value>cn=Administrators,ou=opencms,ou=groups,ou=applications,o=langhua,c=cn</cas:value> </cas:attribute> </cas:attributes> </cas:authenticationSuccess> </cas:serviceResponse>
How to get the module and the source code
The source code of cn.langhua.cas is here.
Source code of OpenCms-LDAP module:
SVN:
http://www.langhua.cn/langhua/modules/ldap/
Username:anon
Password:anon
ViewVC:
http://www.langhua.cn/viewvc/svn/modules/ldap/
Shi Yusen/Beijing Langhua Ltd.
http://langhua.org/
http://langhua.biz/
http://www.langhua.cn/