JASPIC
Table of Contents
Introduction
Tomcat implements JASPIC 1.1 Maintenance Release B (JSR 196). The implementation is primarily intended to enable the integration of 3rd party JASPIC authentication implementations with Tomcat.
JASPIC may be configured dynamically by an application or statically via
  the $CATALINA_BASE/conf/jaspic-providers.xml configuration file.
  If present, a JASPIC configuration will over-ride any
  <login-config> present in web.xml.
Static configuration
AuthConfigProvider
If the 3rd party implementation includes an
    AuthConfigProvider then a web application can be configured to
    use it by nesting the following inside the
    <jaspic-providers> element in
    $CATALINA_BASE/conf/jaspic-providers.xml.
<provider name="any"
          className="fully.qualified.implementation.class.Name"
          layer="HttpServlet"
          appContext="Catalina/localhost /contextPath"
          description="any">
  <property name="see-provider-documentation"
            value="see-provider-documentation" />
</provider>The name and description attributes are not
    used by Tomcat.
The className attribute must be the fully qualified class
    name of the AuthConfigProvider. The implementation may be
    packaged with the web application or in Tomcat's
    $CATALINA_BASE/lib directory.
The layer attribute must be HttpServlet.
The appContext attribute must be exactly the concatenation
    of:
- The engine name
- The forward slash character
- The host name
- A single space
- The context path
If the AuthConfigProvider supports configuration via
    properties these may be specified via <property> elements
    nesting inside the <provide> element.
ServerAuthModule
If the 3rd party implementation only provides an
    ServerAuthModule then it will be necessary to provide a number
    of supporting classes. These may be a custom implementation or,
    alternatively, Tomcat provides a simple wrapper implementation for
    ServerAuthModules.
    
Tomcat's wrapper for ServerAuthModule can be configured
    by nesting the following inside the
    <jaspic-providers> element in
    $CATALINA_BASE/conf/jaspic-providers.xml.
<provider name="any"
          className="org.apache.catalina.authenticator.jaspic.SimpleAuthConfigProvider"
          layer="HttpServlet"
          appContext="Catalina/localhost /contextPath"
          description="any">
  <property name="org.apache.catalina.authenticator.jaspic.ServerAuthModule.1"
            value="fully.qualified.implementation.class.Name" />
  <property name="see-provider-documentation"
            value="see-provider-documentation" />
</provider>The configuration is similar to the AuthConfigProvider in
    the previous section but with some key differences.
The className attribute must be
    org.apache.catalina.authenticator.jaspic.SimpleAuthConfigProvider.
The ServerAuthModule(s) are specified via properties. The
    property name must be
    org.apache.catalina.authenticator.jaspic.ServerAuthModule.n
    where n is the index of the module. The index must start at 1
    an increment in steps of 1 until all modules are defined. The value of the
    property must be the fully qualified class name of the module.
Dynamic configuration
JASPIC modules and configuration can be packaged within a WAR file with the web application. The web application can then register the required JASPIC configuration when it starts using the standard JASPIC APIs.
If parallel deployment is being used then dynamic configuration should not be used. The JASPIC API assumes that a context path is unique for any given host which is not the case when using parallel deployment. When using parallel deployment, static JASPIC configuration should be used. This will require that all versions of the application use the same JASPIC configuration.
3rd party modules
This is not an exhaustive list. The Tomcat community welcomes contributions that add to this section.
Philip Green II's module for Google OAuth 2
The source code for this module along with the documentation which includes details of the necessary Google API configuration is available on GitHub.
A sample configuration for using this module with Tomcat would look like this:
<jaspic-providers xmlns="https://tomcat.apache.org/xml"
                  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                  xsi:schemaLocation="https://tomcat.apache.org/xml jaspic-providers.xsd"
                  version="1.0">
  <provider name="google-oauth"
            className="org.apache.catalina.authenticator.jaspic.SimpleAuthConfigProvider"
            layer="HttpServlet"
            appContext="Catalina/localhost /contextPath"
            description="Google OAuth test">
    <property name="org.apache.catalina.authenticator.jaspic.ServerAuthModule.1"
              value="com.idmworks.security.google.GoogleOAuthServerAuthModule" />
    <property name="oauth.clientid"
              value="obtained-from-Google-console" />
    <property name="oauth.clientsecret"
              value="obtained-from-Google-console" />
    <property name="ignore_missing_login_context"
              value="true" />
  </provider>
</jaspic-providers>