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/* 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 * * http://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.acegisecurity.vote; import org.acegisecurity.Authentication; import org.acegisecurity.AuthorizationServiceException; import org.acegisecurity.ConfigAttribute; import org.acegisecurity.ConfigAttributeDefinition; import org.acegisecurity.acl.AclEntry; import org.acegisecurity.acl.AclManager; import org.acegisecurity.acl.basic.BasicAclEntry; import org.acegisecurity.acl.basic.SimpleAclEntry; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.beans.factory.InitializingBean; import org.springframework.util.Assert; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.util.Iterator; /** * <p>Given a domain object instance passed as a method argument, ensures the principal has appropriate permission * as defined by the {@link AclManager}.</p> * <p>The <code>AclManager</code> is used to retrieve the access control list (ACL) permissions associated with a * domain object instance for the current <code>Authentication</code> object. This class is designed to process {@link * AclEntry}s that are subclasses of {@link org.acegisecurity.acl.basic.BasicAclEntry} only. Generally these are * obtained by using the {@link org.acegisecurity.acl.basic.BasicAclProvider}.</p> * <p>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 <code>AclManager</code> and ensure the principal is {@link * org.acegisecurity.acl.basic.BasicAclEntry#isPermitted(int)} for at least one of the {@link #requirePermission}s.</p> * <p>If the method argument is <code>null</code>, the voter will abstain from voting. If the method argument * could not be found, an {@link org.acegisecurity.AuthorizationServiceException} will be thrown.</p> * <p>In practical terms users will typically setup a number of <code>BasicAclEntryVoter</code>s. Each will have a * different {@link #processDomainObjectClass}, {@link #processConfigAttribute} and {@link #requirePermission} * combination. For example, a small application might employ the following instances of * <code>BasicAclEntryVoter</code>: * <ul> * <li>Process domain object class <code>BankAccount</code>, configuration attribute * <code>VOTE_ACL_BANK_ACCONT_READ</code>, require permission <code>SimpleAclEntry.READ</code></li> * <li>Process domain object class <code>BankAccount</code>, configuration attribute * <code>VOTE_ACL_BANK_ACCOUNT_WRITE</code>, require permission list <code>SimpleAclEntry.WRITE</code> and * <code>SimpleAclEntry.CREATE</code> (allowing the principal to have <b>either</b> of these two permissions</li> * <li>Process domain object class <code>Customer</code>, configuration attribute * <code>VOTE_ACL_CUSTOMER_READ</code>, require permission <code>SimpleAclEntry.READ</code></li> * <li>Process domain object class <code>Customer</code>, configuration attribute * <code>VOTE_ACL_CUSTOMER_WRITE</code>, require permission list <code>SimpleAclEntry.WRITE</code> and * <code>SimpleAclEntry.CREATE</code></li> * </ul> * Alternatively, you could have used a common superclass or interface for the {@link #processDomainObjectClass} * if both <code>BankAccount</code> and <code>Customer</code> had common parents.</p> * <p>If the principal does not have sufficient permissions, the voter will vote to deny access.</p> * <p>The <code>AclManager</code> is allowed to return any implementations of <code>AclEntry</code> it wishes. * However, this provider will only be able to validate against <code>AbstractBasicAclEntry</code>s, and thus a vote * to deny access will be made if no <code>AclEntry</code> is of type <code>AbstractBasicAclEntry</code>.</p> * <p>All comparisons and prefixes are case sensitive.</p> * * @author Ben Alex * @version $Id: BasicAclEntryVoter.java 1766 2006-11-26 04:47:43Z benalex $ */ public class BasicAclEntryVoter extends AbstractAclVoter implements InitializingBean { //~ Static fields/initializers ===================================================================================== private static final Log logger = LogFactory.getLog(BasicAclEntryVoter.class); //~ Instance fields ================================================================================================ private AclManager aclManager; private String internalMethod; private String processConfigAttribute; private int[] requirePermission; //~ Methods ======================================================================================================== public void afterPropertiesSet() throws Exception { Assert.notNull(processConfigAttribute, "A processConfigAttribute is mandatory"); Assert.notNull(aclManager, "An aclManager is mandatory"); if ((requirePermission == null) || (requirePermission.length == 0)) { throw new IllegalArgumentException("One or more requirePermission entries is mandatory"); } } public AclManager getAclManager() { return aclManager; } /** * 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 <code>null</code> to use the domain object, or the name of a method (that requires no arguments) that * should be invoked to obtain an <code>Object</code> which will be the domain object used for ACL * evaluation */ public String getInternalMethod() { return internalMethod; } public String getProcessConfigAttribute() { return processConfigAttribute; } public int[] getRequirePermission() { return requirePermission; } public void setAclManager(AclManager aclManager) { this.aclManager = aclManager; } public void setInternalMethod(String internalMethod) { this.internalMethod = internalMethod; } public void setProcessConfigAttribute(String processConfigAttribute) { this.processConfigAttribute = processConfigAttribute; } public void setRequirePermission(int[] requirePermission) { this.requirePermission = requirePermission; } /** * Allow setting permissions with String literals instead of integers as {@link #setRequirePermission(int[])} * * @param requirePermission Permission literals * @see SimpleAclEntry#parsePermissions(String[]) for valid values */ public void setRequirePermissionFromString(String[] requirePermission) { setRequirePermission(SimpleAclEntry.parsePermissions(requirePermission)); } public boolean supports(ConfigAttribute attribute) { if ((attribute.getAttribute() != null) && attribute.getAttribute().equals(getProcessConfigAttribute())) { return true; } else { return false; } } public int vote(Authentication authentication, Object object, ConfigAttributeDefinition config) { Iterator iter = config.getConfigAttributes(); while (iter.hasNext()) { ConfigAttribute attr = (ConfigAttribute) iter.next(); if (this.supports(attr)) { // 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) { if (logger.isDebugEnabled()) { logger.debug("Voting to abstain - domainObject is null"); } return AccessDecisionVoter.ACCESS_ABSTAIN; } // Evaluate if we are required to use an inner domain object if ((internalMethod != null) && !"".equals(internalMethod)) { try { Class clazz = domainObject.getClass(); Method method = clazz.getMethod(internalMethod, new Class[] {}); domainObject = method.invoke(domainObject, new Object[] {}); } catch (NoSuchMethodException nsme) { throw new AuthorizationServiceException("Object of class '" + domainObject.getClass() + "' does not provide the requested internalMethod: " + internalMethod); } catch (IllegalAccessException iae) { if (logger.isDebugEnabled()) { logger.debug("IllegalAccessException", iae); if (iae.getCause() != null) { logger.debug("Cause: " + iae.getCause().getMessage(), iae.getCause()); } } throw new AuthorizationServiceException("Problem invoking internalMethod: " + internalMethod + " for object: " + domainObject); } catch (InvocationTargetException ite) { if (logger.isDebugEnabled()) { logger.debug("InvocationTargetException", ite); if (ite.getCause() != null) { logger.debug("Cause: " + ite.getCause().getMessage(), ite.getCause()); } } throw new AuthorizationServiceException("Problem invoking internalMethod: " + internalMethod + " for object: " + domainObject); } } // Obtain the ACLs applicable to the domain object AclEntry[] acls = aclManager.getAcls(domainObject, authentication); // If principal has no permissions for domain object, deny if ((acls == null) || (acls.length == 0)) { if (logger.isDebugEnabled()) { logger.debug("Voting to deny access - no ACLs returned for this principal"); } return AccessDecisionVoter.ACCESS_DENIED; } // Principal has some permissions for domain object, check them for (int i = 0; i < acls.length; i++) { // Locate processable AclEntrys if (acls[i] instanceof BasicAclEntry) { BasicAclEntry processableAcl = (BasicAclEntry) acls[i]; // See if principal has any of the required permissions for (int y = 0; y < requirePermission.length; y++) { if (processableAcl.isPermitted(requirePermission[y])) { if (logger.isDebugEnabled()) { logger.debug("Voting to grant access"); } return AccessDecisionVoter.ACCESS_GRANTED; } } } } // No permissions match if (logger.isDebugEnabled()) { logger.debug( "Voting to deny access - ACLs returned, but insufficient permissions for this principal"); } return AccessDecisionVoter.ACCESS_DENIED; } } // No configuration attribute matched, so abstain return AccessDecisionVoter.ACCESS_ABSTAIN; } }