org.springframework.security.acls.AclEntryVoter Maven / Gradle / Ivy
/*
* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.security.acls;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import org.aopalliance.intercept.MethodInvocation;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.security.access.AuthorizationServiceException;
import org.springframework.security.access.ConfigAttribute;
import org.springframework.security.access.vote.AbstractAclVoter;
import org.springframework.security.acls.domain.ObjectIdentityRetrievalStrategyImpl;
import org.springframework.security.acls.domain.SidRetrievalStrategyImpl;
import org.springframework.security.acls.model.Acl;
import org.springframework.security.acls.model.AclService;
import org.springframework.security.acls.model.NotFoundException;
import org.springframework.security.acls.model.ObjectIdentity;
import org.springframework.security.acls.model.ObjectIdentityRetrievalStrategy;
import org.springframework.security.acls.model.Permission;
import org.springframework.security.acls.model.Sid;
import org.springframework.security.acls.model.SidRetrievalStrategy;
import org.springframework.security.core.Authentication;
import org.springframework.util.Assert;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;
/**
*
* Given a domain object instance passed as a method argument, ensures the principal has
* appropriate permission as indicated by the {@link AclService}.
*
* The AclService is used to retrieve the access control list (ACL) permissions
* associated with a domain object instance for the current Authentication
* object.
*
* The voter will vote if any {@link ConfigAttribute#getAttribute()} matches the
* {@link #processConfigAttribute}. The provider will then locate the first method
* argument of type {@link #processDomainObjectClass}. Assuming that method argument is
* non-null, the provider will then lookup the ACLs from the AclManager and
* ensure the principal is {@link Acl#isGranted(List, List, boolean)} when presenting the
* {@link #requirePermission} array to that method.
*
* If the method argument is null, the voter will abstain from voting. If the
* method argument could not be found, an {@link AuthorizationServiceException} will be
* thrown.
*
* In practical terms users will typically setup a number of AclEntryVoters. Each
* will have a different {@link #setProcessDomainObjectClass processDomainObjectClass},
* {@link #processConfigAttribute} and {@link #requirePermission} combination. For
* example, a small application might employ the following instances of
* AclEntryVoter:
*
* - Process domain object class
BankAccount, configuration attribute
* VOTE_ACL_BANK_ACCONT_READ, require permission
* BasePermission.READ
* - Process domain object class
BankAccount, configuration attribute
* VOTE_ACL_BANK_ACCOUNT_WRITE, require permission list
* BasePermission.WRITE and BasePermission.CREATE (allowing the
* principal to have either of these two permissions)
* - Process domain object class
Customer, configuration attribute
* VOTE_ACL_CUSTOMER_READ, require permission
* BasePermission.READ
* - Process domain object class
Customer, configuration attribute
* VOTE_ACL_CUSTOMER_WRITE, require permission list
* BasePermission.WRITE and BasePermission.CREATE
*
* Alternatively, you could have used a common superclass or interface for the
* {@link #processDomainObjectClass} if both BankAccount and
* Customer had common parents.
*
*
* If the principal does not have sufficient permissions, the voter will vote to deny
* access.
*
*
* All comparisons and prefixes are case sensitive.
*
* @author Ben Alex
*/
public class AclEntryVoter extends AbstractAclVoter {
private static final Log logger = LogFactory.getLog(AclEntryVoter.class);
private final AclService aclService;
private final String processConfigAttribute;
private final List requirePermission;
private ObjectIdentityRetrievalStrategy objectIdentityRetrievalStrategy = new ObjectIdentityRetrievalStrategyImpl();
private SidRetrievalStrategy sidRetrievalStrategy = new SidRetrievalStrategyImpl();
private String internalMethod;
public AclEntryVoter(AclService aclService, String processConfigAttribute, Permission[] requirePermission) {
Assert.notNull(processConfigAttribute, "A processConfigAttribute is mandatory");
Assert.notNull(aclService, "An AclService is mandatory");
Assert.isTrue(!ObjectUtils.isEmpty(requirePermission), "One or more requirePermission entries is mandatory");
this.aclService = aclService;
this.processConfigAttribute = processConfigAttribute;
this.requirePermission = Arrays.asList(requirePermission);
}
/**
* Optionally specifies a method of the domain object that will be used to obtain a
* contained domain object. That contained domain object will be used for the ACL
* evaluation. This is useful if a domain object contains a parent that an ACL
* evaluation should be targeted for, instead of the child domain object (which
* perhaps is being created and as such does not yet have any ACL permissions)
* @return null to use the domain object, or the name of a method (that
* requires no arguments) that should be invoked to obtain an Object
* which will be the domain object used for ACL evaluation
*/
protected String getInternalMethod() {
return this.internalMethod;
}
public void setInternalMethod(String internalMethod) {
this.internalMethod = internalMethod;
}
protected String getProcessConfigAttribute() {
return this.processConfigAttribute;
}
public void setObjectIdentityRetrievalStrategy(ObjectIdentityRetrievalStrategy objectIdentityRetrievalStrategy) {
Assert.notNull(objectIdentityRetrievalStrategy, "ObjectIdentityRetrievalStrategy required");
this.objectIdentityRetrievalStrategy = objectIdentityRetrievalStrategy;
}
public void setSidRetrievalStrategy(SidRetrievalStrategy sidRetrievalStrategy) {
Assert.notNull(sidRetrievalStrategy, "SidRetrievalStrategy required");
this.sidRetrievalStrategy = sidRetrievalStrategy;
}
@Override
public boolean supports(ConfigAttribute attribute) {
return (attribute.getAttribute() != null) && attribute.getAttribute().equals(getProcessConfigAttribute());
}
@Override
public int vote(Authentication authentication, MethodInvocation object, Collection attributes) {
for (ConfigAttribute attr : attributes) {
if (!supports(attr)) {
continue;
}
// Need to make an access decision on this invocation
// Attempt to locate the domain object instance to process
Object domainObject = getDomainObjectInstance(object);
// If domain object is null, vote to abstain
if (domainObject == null) {
logger.debug("Voting to abstain - domainObject is null");
return ACCESS_ABSTAIN;
}
// Evaluate if we are required to use an inner domain object
if (StringUtils.hasText(this.internalMethod)) {
domainObject = invokeInternalMethod(domainObject);
}
// Obtain the OID applicable to the domain object
ObjectIdentity objectIdentity = this.objectIdentityRetrievalStrategy.getObjectIdentity(domainObject);
// Obtain the SIDs applicable to the principal
List sids = this.sidRetrievalStrategy.getSids(authentication);
Acl acl;
try {
// Lookup only ACLs for SIDs we're interested in
acl = this.aclService.readAclById(objectIdentity, sids);
}
catch (NotFoundException ex) {
logger.debug("Voting to deny access - no ACLs apply for this principal");
return ACCESS_DENIED;
}
try {
if (acl.isGranted(this.requirePermission, sids, false)) {
logger.debug("Voting to grant access");
return ACCESS_GRANTED;
}
logger.debug("Voting to deny access - ACLs returned, but insufficient permissions for this principal");
return ACCESS_DENIED;
}
catch (NotFoundException ex) {
logger.debug("Voting to deny access - no ACLs apply for this principal");
return ACCESS_DENIED;
}
}
// No configuration attribute matched, so abstain
return ACCESS_ABSTAIN;
}
private Object invokeInternalMethod(Object domainObject) {
try {
Class domainObjectType = domainObject.getClass();
Method method = domainObjectType.getMethod(this.internalMethod, new Class[0]);
return method.invoke(domainObject);
}
catch (NoSuchMethodException ex) {
throw new AuthorizationServiceException("Object of class '" + domainObject.getClass()
+ "' does not provide the requested internalMethod: " + this.internalMethod);
}
catch (IllegalAccessException ex) {
logger.debug("IllegalAccessException", ex);
throw new AuthorizationServiceException(
"Problem invoking internalMethod: " + this.internalMethod + " for object: " + domainObject);
}
catch (InvocationTargetException ex) {
logger.debug("InvocationTargetException", ex);
throw new AuthorizationServiceException(
"Problem invoking internalMethod: " + this.internalMethod + " for object: " + domainObject);
}
}
}