--- /dev/null
+/*
+ * AttributeRequestor.java
+ *
+ * Generate a SAMLRequest to the AA for Attributes, then process the
+ * reply. In C++, this logic was InternalCCacheEntry::getNewResponse()
+ * in shib-ccache.cpp.
+ *
+ * The User Authentication was previously processed by ShibPOSTProfile
+ * and was stored by SessionManager in a Session object. Although the
+ * attributes might be fetched immediately, that is a strategy issue.
+ * In Java, we isolate the Attribute fetch in this separate module.
+ *
+ * The Session block retains a copy of the original SAMLStatement from
+ * the POST, and it contains information about the remote Entity.
+ * However, the POST came from the HS (or IIDPProvider if you want to
+ * use SAML 2 terms), and this transaction has to go to the AA. So
+ * Metadata must be used to obtain the AttributeAuthorityRole and its
+ * associated Endpoint (URL).
+ *
+ * The ApplicationInfo object for the configured Application presents
+ * a getAttributeDesignators method that can return a list of attributes
+ * to specify in the request. However, I can find no configuration element
+ * that corresponds to this, and no example logic. For now that method
+ * returns an empty collection and no particular attributes are requested.
+ *
+ * The actual SSL session and exchange of data is performed by OpenSAML.
+ * Our interface to SAML is through the separate ShibBind module. The
+ * layers of processing and responsibilites need to be understood.
+ *
+ * ShibBind uses the Metadata for the User's ID Providing Entity to
+ * locate the AttributeAuthorityRole and therefore the AA URL. This
+ * is passed to OpenSAML along with the request. Upon return, if any
+ * statements are signed it is the responsiblilty of ShibBind to call
+ * the Trust implementations to validate the signatures.
+ *
+ * This module then checks, by calling the isSigned() property of
+ * SAMLObjects, to make sure that everything that is supposed to be
+ * signed actually was signed. ShibBind knows if a signature is valid,
+ * but this module knows if a signature was requred. This module also
+ * applies AAP to examine attributes and values and discard those that
+ * the policy doesn't accept.
+ *
+ * Recovery Context: All exceptions handled and logged internally.
+ * --------------------
+ * Copyright 2002, 2004
+ * University Corporation for Advanced Internet Development, Inc.
+ * All rights reserved
+ * [Thats all we have to say to protect ourselves]
+ * Your permission to use this code is governed by "The Shibboleth License".
+ * A copy may be found at http://shibboleth.internet2.edu/license.html
+ * [Nothing in copyright law requires license text in every file.]
+ */
+package edu.internet2.middleware.shibboleth.target;
+
+import java.util.Collection;
+import java.util.Iterator;
+
+import org.apache.log4j.Logger;
+import org.opensaml.SAMLAssertion;
+import org.opensaml.SAMLAttributeQuery;
+import org.opensaml.SAMLException;
+import org.opensaml.SAMLRequest;
+import org.opensaml.SAMLResponse;
+import org.opensaml.SAMLSubject;
+
+import x0.maceShibbolethTargetConfig1.ApplicationDocument.Application;
+
+import edu.internet2.middleware.shibboleth.metadata.AttributeAuthorityRole;
+import edu.internet2.middleware.shibboleth.metadata.EntityDescriptor;
+import edu.internet2.middleware.shibboleth.metadata.MetadataException;
+import edu.internet2.middleware.shibboleth.target.ServiceProviderConfig.ApplicationInfo;
+
+/**
+ * A static class with a static method. No objects are created
+ *
+ * @author Howard Gilbert
+ */
+public class AttributeRequestor {
+
+ private static Logger log = Logger.getLogger(AttributeRequestor.class);
+ private static ServiceProviderContext context = ServiceProviderContext.getInstance();
+
+ private AttributeRequestor() {} // Prevent instantiation
+
+ /**
+ * Request SAML Attribute response from AA
+ *
+ * @param session Session object (from authentication POST)
+ * @return true if Attributes successfully stored in the Session
+ * @throws MetadataException If Origin has no configured AA
+ * @throws SAMLException If there is a problem with the reply
+ */
+ static
+ boolean // return false if attributes are not fetched
+ fetchAttributes(
+ Session session){
+
+ log.debug("Fetching attributes for session "+session.getKey()+
+ " from "+session.getEntityId());
+
+ // Get local references to configuration objects
+ ServiceProviderConfig config = context.getServiceProviderConfig();
+ ApplicationInfo appinfo = config.getApplication(session.getApplicationId());
+
+ // The Entity name was fed by by ShibPOSTProfile.accept(). Look it up now.
+ EntityDescriptor entity = appinfo.getEntityDescriptor(session.getEntityId());
+ if (entity==null) {
+ log.error("Entity(Site) deleted from Metadata since authentication POST received: "+session.getEntityId());
+ return false;
+ }
+ Application applicationConfig = appinfo.getApplicationConfig();
+ boolean signRequest = applicationConfig.getSignRequest();
+ boolean signedAssertions = applicationConfig.getSignedAssertions();
+ boolean signedResponse = applicationConfig.getSignedResponse();
+
+ SAMLRequest request = null;
+
+ AttributeAuthorityRole aa =
+ entity.getAttributeAuthorityRole(); // throws MetadataException
+ if (aa==null) {
+ log.error("No Attribute Authority in Metadata for ID="+entity.getId());
+ return false;
+ }
+
+ // Build the Attribute Query
+ SAMLAttributeQuery query = null;
+ SAMLSubject subject = session.getAuthenticationStatement().getSubject();
+ log.debug("Subject (Handle) is "+subject.getName());
+ Collection attributeDesignators = appinfo.getAttributeDesignators();
+ try {
+ query =
+ new SAMLAttributeQuery(
+ subject, // Subject (i.e. Handle) from authentication
+ entity.getId(), // ID of user's Entity (i.e. Origin Site)
+ attributeDesignators // Attributes to request, null for everything
+ );
+
+ // Wrap the Query in a request
+ request = new SAMLRequest();
+ request.setQuery(query);
+ } catch (SAMLException e) {
+ log.error("AttributeRequestor unable to build SAML Query for Session "+session.getKey());
+ return false;
+ }
+
+ if (signRequest) {
+ // TODO Attribute requests are not typically signed, but add
+ // code to do so optionally later.
+ }
+
+ // ShibBinding will extract URLs from the Metadata and build
+ // parameters so SAML can create the session. It also interfaces
+ // to Trust to verify that any signed objects have trusted signatures.
+ ShibBinding binding = new ShibBinding(session.getApplicationId());
+ SAMLResponse response = null;
+ try {
+ response = binding.send(request,aa,null,null);
+ } catch (SAMLException e) {;} // response will be null
+ if (response==null) {
+ log.error("AttributeRequestor Query to remote AA returned no response from "+session.getEntityId());
+ return false;
+ }
+
+ if (signedResponse &&
+ !response.isSigned()) {
+ log.error("AttributeRequestor rejected unsigned attribute response from "+session.getEntityId());
+ return false;
+ }
+
+ // Check each assertion in the response.
+ Iterator assertions = response.getAssertions();
+ while (assertions.hasNext()) {
+ SAMLAssertion assertion = (SAMLAssertion) assertions.next();
+ if (signedAssertions &&
+ !assertion.isSigned()) {
+ log.warn("AttributeRequestor has removed unsigned assertion from response from "+session.getEntityId());
+ assertions.remove();
+ continue;
+ }
+
+ appinfo.applyAAP(entity,assertion); // apply each AAP to this assertion
+
+ if (!assertion.getStatements().hasNext())
+ assertions.remove(); // AAP rejected all statements for this assertion
+ }
+
+ // A response may end up with no attributes, but that is not an error.
+ // Maybe there is just nothing important to say about this user.
+
+ session.setAttributeResponse(response); // Save response in Session object
+ return true;
+ }
+
+}