Institutions typically use different ways (Shibboleth, LDAP, etc.) to authenticate users. It is difficult to achieve a one-size-fits-all deployment to address all the different authentication in OLE. This bottleneck can be cleared by using a reverse proxy.
Reverse Proxy
A reverse proxy server is a specialized web server that inspects incoming requests and forwards them to another internal web server after any local processing is completed. It also inspects and makes sure that any response from the internal web server containing URLs are updated with the proper host address.
In our case, the reverse proxy server hosts an Apache HTTP server with modules to implement a proxy (mod_proxy) which would also host the authentication logic. Following successful authentication, the user is passed in the RequestHeader and the request is forwarded to the Tomcat server hosting OLE. Unsuccessful authentication is handled appropriately.
To get this working successfully a few configurations are needed. The significant ones are listed below for reference.
Configurations on the Apache Tomcat side
Authentication Filter Class
A custom authentication filter is not needed. The behavior of the default HttpServletRequest class is inline with expectations, as it picks up the REMOTE_USER passed in the RequestHeader.
Changes in web.xml
The web.xml file is found at <Application-root>/WEB-INF/
The file contains references to a filter, DummyLoginFilter, which needs to be removed. The filter class configured is DevelopmentLoginFilter which helps in forwarding the user to the login page without any need for password for authentication.
The following lines are to be removed from web.xml
<filter>
<filter-name>DummyLoginFilter</filter-name>
<filter-class>org.kuali.ole.sys.web.filter.DevelopmentLoginFilter</filter-class>
<init-param>
<param-name>loginUser</param-name>
<param-value>ole-quickstart</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>DummyLoginFilter</filter-name>
<servlet-name>action</servlet-name>
</filter-mapping>
<filter-mapping>
<filter-name>DummyLoginFilter</filter-name>
<servlet-name>dwr-invoker</servlet-name>
</filter-mapping>
<filter-mapping>
<filter-name>DummyLoginFilter</filter-name>
<servlet-name>batchFileUpload</servlet-name>
</filter-mapping>
Changes in server.xml
The server.xml file is found at <CATALINA_HOME>/conf/
If SSL is used, there could be problems while accessing certain search pages. This is because the URL is formed by using request.getRequestURL(), which ultimately comes from "scheme" part of the connector configuration in server.xml. So the scheme attribute should be set to 'https' and the port attribute to '443' for OLE to generate the proper URLs.
<Connector port="8443" protocol="HTTP/1.1"
connectionTimeout="20000"
URIEncoding="UTF-8"
scheme="https"
proxyPort="443"/>
It is also imperative to check that all URL related information in common-config.xml and other files use relative URLs.
Backdoor Login
To remove the Backdoor Login (
) from the screen, the value in System Parameter, SHOW_BACK_DOOR_LOGIN_IND, can be set to 'N'.
Logout
The Logout button (
) invalidates the OLE session. However, the redirect URL needs to be configured. Currently it defaults to the Application URL.
The configuration can be specified as a parameter in the olefs-config-defaults.xml file as below
<param name="rice.portal.logout.redirectUrl">[Specify URL here]</param>
Alternatively, a System Parameter can be created with Namespace code KR-NS and Parameter Name, LOGOFF_REDIRECT_URL and the URL specified in Parameter Value and OLE would pick the URL as the redirect link. The value in the System Parameter overrides the configuration in olefs-config-defaults.xml.
It should be noted that though the Logout button invalidates the OLE session, the session established by the application residing on the Proxy Server may continue and may need to be handled externally.
Configurations on the Apache HTTP side
The configurations are done in the httpd.conf file.
Pass the REMOTE_USER in Header
The Apache 'headers' module needs to be enabled for this to work.
In the Location directive for the authenticated olefs app, right after the ProxyPass lines, the RequestHeader is set.
RequestHeader set Remote-User %{REMOTE_USER}s
Force HTTPS
The Apache 'rewrite' module needs to be enabled for this to work.
Under the Virtual Host Config, the rewrite conditions are to be mentioned.
RewriteCond %{HTTPS} on
RewriteCond %{REQUEST_URI} (.*)olefs(/portal\.do)?$
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI}
Sample Configuration Files
Source:
Version related issues
Apache versions prior to Apache 2.4.4 (especially Apache 2.2.x shipped with Red Hat Enterprise Linux 6.x) cannot forward PATCH requests via the AJP protocol, which can interfere with some of OLE's APIs.
If you are experiencing HTTP 501 ("Method Not Implemented") errors, this may be the cause. Check your Apache version and error logs for messages such as "ajp_marshal_into_msgb - No such method PATCH".
Possible Fixes
- Use mod_proxy_http instead of mod_proxy_ajp in your proxy setup.
- Use at least Apache 2.4.4 with mod_proxy_ajp.
- (Unverified) Use mod_jk instead of mod_proxy_ajp.