This Grouper enhancement facilitates secure subject attribute release. This could be used to protect FERPA information, create private subdomains of Grouper where users from one might not be able to see subjects in another, or attributes which can only be seen by certain subjects.
In Grouper 2.0 and previous there is no subject attribute security (unless it is baked into the custom subject source). This is only available in v2.1 and more recent.
This is an interface point that can be implemented in Java to retrieve more attributes about a subject (i.e. attributes that may require another query, or security, or attributes not always needed when subjects are resolved). When you implement this interface you should try to only use one (or few) queries, since this will be called a lot (for filters at least).
Implement the interface SubjectCustomizer by extending the class: edu.internet2.middleware.grouper.subj.SubjectCustomizerBase
/**
* add the ability to decorate a list of subjects with more attributes.
* note, while you are decorating, you can check security to see if the
* groupersession is allowed to see those attributes
* @author mchyzer
*
*/
public interface SubjectCustomizer {
/**
* decorate subjects based on attributes requested
* @param grouperSession
* @param subjects
* @param attributeNamesRequested
* @return the subjects if same set, or make a new set
*/
public Set<Subject> decorateSubjects(GrouperSession grouperSession, Set<Subject> subjects, Collection<String> attributeNamesRequested);
/**
* you can edit the subjects (or replace), but you shouldnt remove them
* @param grouperSession
* @param subjects
* @param findSubjectsInStemName if this is a findSubjectsInStem call, this is the stem name. This is useful
* to filter when searching for subjects to add to a certain group
* @return the subjects if same set, or make a new set
*/
public Set<Subject> filterSubjects(GrouperSession grouperSession, Set<Subject> subjects, String findSubjectsInStemName);
}
Configure this in the grouper.properties:
# customize subjects by implementing this interface: edu.internet2.middleware.grouper.subj.SubjectCustomizer # or extending this class: edu.internet2.middleware.grouper.subj.SubjectCustomizerBase (recommended) # note the instance will be reused to make sure it is threadsafe subjects.customizer.className =
Note that the filter and decorator are batched for performance reasons, which is also why this is not configured in the subject source
The filterSubjects() method is called on each SubjectFinder call. The decorateSubjects() is called when web services resolve subjects
There are two ways to protect data.
1. You can change the data to protect it, the user will see the subject, but might only see the netId instead of the name. Or it could just say (protected-data)
2. You could remove the subject from the results and the user will not know the subject exists
Here is an example of hiding names of students to users who aren't allowed to see them (note, you can still search by private information potentially, though you will not see the result. If you want something more complex you might need a custom source, or only have public information in the search field)
/**
* filter students private information out from people who cant see them
* @author mchyzer
*
*/
public class SubjectCustomizerForDecoratorTestingHideStudentData extends SubjectCustomizerBase {
/** student (protected data) group name */
public static final String STUDENT_GROUP_NAME = "apps:subjectSecurity:groups:student";
/** privileged employee group name */
public static final String PRIVILEGED_EMPLOYEE_GROUP_NAME = "apps:subjectSecurity:groups:privilegedEmployee";
/** source id we care about */
private static final String SOURCE_ID = "jdbc";
/**
* @see SubjectCustomizer#filterSubjects(GrouperSession, Set, String)
*/
@Override
public Set<Subject> filterSubjects(GrouperSession grouperSession, Set<Subject> subjects, String findSubjectsInStemName) {
//nothing to do if no results
if (GrouperUtil.length(subjects) == 0) {
return subjects;
}
//get results in one query
MembershipResult groupMembershipResult = new MembershipFinder().assignCheckSecurity(false).addGroup(STUDENT_GROUP_NAME)
.addGroup(PRIVILEGED_EMPLOYEE_GROUP_NAME).addSubjects(subjects).addSubject(grouperSession.getSubject())
.findMembershipResult();
//see if the user is privileged
boolean grouperSessionIsPrivileged = groupMembershipResult.hasGroupMembership(PRIVILEGED_EMPLOYEE_GROUP_NAME, grouperSession.getSubject());
//if so, we are done, they can see stuff
if (grouperSessionIsPrivileged) {
return subjects;
}
//loop through the subjects and see which are students, change their name and description to be their netId, with no other attributes
Set<Subject> results = new LinkedHashSet<Subject>();
for (Subject subject : subjects) {
if (StringUtils.equals(SOURCE_ID, subject.getSourceId()) && groupMembershipResult.hasGroupMembership(STUDENT_GROUP_NAME, subject)) {
String loginid = subject.getAttributeValue("loginid");
Subject replacementSubject = new SubjectImpl(subject.getId(), loginid, loginid, subject.getTypeName(), subject.getSourceId());
results.add(replacementSubject);
} else {
results.add(subject);
}
}
return results;
}
}
API access
In order to use the decorator part, you need to make an extra call to the SubjectFinder for your subjects
SubjectFinder.decorateSubjects(GrouperSession.staticGrouperSession(), subjects, subjectAttributesForDecoratorSet);
WS access
You can use this via WS by configuring which subject attributes will trigger a call to the SubjectFinder.decorateSubjects() method in the grouper-ws.properties:
# customize subjects by implementing this interface: edu.internet2.middleware.grouper.subj.SubjectCustomizer # or extending this class: edu.internet2.middleware.grouper.subj.SubjectCustomizerBase (recommended) # note the instance will be reused to make sure it is threadsafe subjects.customizer.className = edu.internet2.middleware.grouper.subj.decoratorExamples.SubjectCustomizerForDecoratorExtraAttributes
Then when the user requests certain attributes for subjects, if they are allowed to go to the customizer via the config above, it will trigger a call to it. Here is an example client call:
C:\mchyzer\grouper\trunk\grouperClient\dist>java \-jar grouperClient.jar \--operation=getSubjectsWs \--subjectIds=test.subject.1 \--subjectAttributeNames=title \--outputTemplate="Index: ${index}: success: ${success}, code: ${wsSubject.resultCode}, subject:"${wsSubject.id}, title: ${wsSubject.attributeValues\[0\]}$newline$"
Index: 0: success: T, code: SUCCESS, subject: test.subject.1, title: title1
Here is the XML (POX) request:
<WsRestGetSubjectsRequest> <subjectAttributeNames> <string>title</string> </subjectAttributeNames> <wsSubjectLookups> <WsSubjectLookup> <subjectId>test.subject.1</subjectId> </WsSubjectLookup> </wsSubjectLookups> </WsRestGetSubjectsRequest>
And here is the response (the title for this subject is "title1"
<WsGetSubjectsResults> <subjectAttributeNames> <string>title</string> </subjectAttributeNames> <wsSubjects> <WsSubject> <resultCode>SUCCESS</resultCode> <success>T</success> <id>test.subject.1</id> <name>my name is test.subject.1</name> <sourceId>jdbc</sourceId> <attributeValues> <string>title1</string> </attributeValues> </WsSubject> </wsSubjects> <resultMetadata> <resultCode>SUCCESS</resultCode> <resultMessage>Queried 1 subjects</resultMessage> <success>T</success> </resultMetadata> <responseMetadata> <resultWarnings></resultWarnings> <millis>983</millis> <serverVersion>2.1.0</serverVersion> </responseMetadata> </WsGetSubjectsResults>
Example: collaboration groups
Here is an example where subjects not in collab groups are filtered from users not in that group
package edu.internet2.middleware.grouper.subj;
import java.util.LinkedHashSet;
import java.util.Set;
import org.apache.commons.collections.CollectionUtils;
import org.apache.commons.lang.StringUtils;
import edu.internet2.middleware.grouper.GrouperSession;
import edu.internet2.middleware.grouper.membership.GroupMembershipResult;
import edu.internet2.middleware.grouper.util.GrouperUtil;
import edu.internet2.middleware.subject.Subject;
/**
* filter out subjects not in the collaboration group
* @author mchyzer
*
*/
public class SubjectCustomizerForDecoratorTesting2 extends SubjectCustomizerBase {
/** student (protected data) group name */
private static final String COLLAB_STEM_NAME = "collaboration:collabGroups";
/** privileged employee group name */
private static final String PRIVILEGED_ADMIN_GROUP_NAME = "collaboration:etc:privilegedAdmin";
/** source id we care about */
private static final String SOURCE_ID = "jdbc";
/**
* @see SubjectCustomizer#filterSubjects(GrouperSession, Set)
*/
@Override
public Set<Subject> filterSubjects(GrouperSession grouperSession, Set<Subject> subjects) {
//nothing to do if no results
if (GrouperUtil.length(subjects) == 0) {
return subjects;
}
//get results in one query
GroupMembershipResult groupMembershipResult = calculateMembershipsInStems(subjects, IncludeGrouperSessionSubject.TRUE,
GrouperUtil.toSet(PRIVILEGED_ADMIN_GROUP_NAME), GrouperUtil.toSet(COLLAB_STEM_NAME));
//see if the user is privileged
boolean grouperSessionIsPrivileged = groupMembershipResult.hasMembership(PRIVILEGED_ADMIN_GROUP_NAME, grouperSession.getSubject());
//if so, we are done, they can see stuff
if (grouperSessionIsPrivileged) {
return subjects;
}
//get the group names that the grouper session subject is in
Set<String> grouperSessionGroupNames = groupMembershipResult.groupNamesInStem(grouperSession.getSubject(), COLLAB_STEM_NAME);
//loop through the subjects and see which collab groups the users are in
Set<Subject> results = new LinkedHashSet<Subject>();
for (Subject subject : subjects) {
//only protect one source
if (!StringUtils.equals(SOURCE_ID, subject.getSourceId())) {
results.add(subject);
} else {
Set<String> subjectGroupNames = groupMembershipResult.groupNamesInStem(subject, COLLAB_STEM_NAME);
if (CollectionUtils.containsAny(grouperSessionGroupNames, subjectGroupNames)) {
results.add(subject);
}
}
}
return results;
}
}
Example: hide student data to most users
Here is an example where student data is hidden to most users
package edu.internet2.middleware.grouper.subj.decoratorExamples;
import java.util.LinkedHashSet;
import java.util.Set;
import org.apache.commons.lang.StringUtils;
import edu.internet2.middleware.grouper.GrouperSession;
import edu.internet2.middleware.grouper.MembershipFinder;
import edu.internet2.middleware.grouper.membership.MembershipResult;
import edu.internet2.middleware.grouper.subj.SubjectCustomizer;
import edu.internet2.middleware.grouper.subj.SubjectCustomizerBase;
import edu.internet2.middleware.grouper.util.GrouperUtil;
import edu.internet2.middleware.subject.Subject;
import edu.internet2.middleware.subject.provider.SubjectImpl;
/**
* filter students private information out from people who cant see them
* @author mchyzer
*
*/
public class SubjectCustomizerForDecoratorTestingHideStudentData extends SubjectCustomizerBase {
/** student (protected data) group name */
public static final String STUDENT_GROUP_NAME = "apps:subjectSecurity:groups:student";
/** privileged employee group name */
public static final String PRIVILEGED_EMPLOYEE_GROUP_NAME = "apps:subjectSecurity:groups:privilegedEmployee";
/** source id we care about */
private static final String SOURCE_ID = "jdbc";
/**
* @see SubjectCustomizer#filterSubjects(GrouperSession, Set, String)
*/
@Override
public Set<Subject> filterSubjects(GrouperSession grouperSession, Set<Subject> subjects, String findSubjectsInStemName) {
//nothing to do if no results
if (GrouperUtil.length(subjects) == 0) {
return subjects;
}
//get results in one query
MembershipResult groupMembershipResult = new MembershipFinder().assignCheckSecurity(false).addGroup(STUDENT_GROUP_NAME)
.addGroup(PRIVILEGED_EMPLOYEE_GROUP_NAME).addSubjects(subjects).addSubject(grouperSession.getSubject())
.findMembershipResult();
//see if the user is privileged
boolean grouperSessionIsPrivileged = groupMembershipResult.hasGroupMembership(PRIVILEGED_EMPLOYEE_GROUP_NAME, grouperSession.getSubject());
//if so, we are done, they can see stuff
if (grouperSessionIsPrivileged) {
return subjects;
}
//loop through the subjects and see which are students, change their name and description to be their netId, with no other attributes
Set<Subject> results = new LinkedHashSet<Subject>();
for (Subject subject : subjects) {
if (StringUtils.equals(SOURCE_ID, subject.getSourceId()) && groupMembershipResult.hasGroupMembership(STUDENT_GROUP_NAME, subject)) {
String loginid = subject.getAttributeValue("loginid");
Subject replacementSubject = new SubjectImpl(subject.getId(), loginid, loginid, subject.getTypeName(), subject.getSourceId());
results.add(replacementSubject);
} else {
results.add(subject);
}
}
return results;
}
}
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