001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.shiro.authz.aop;
020
021import org.apache.shiro.authz.AuthorizationException;
022
023import javax.annotation.security.RolesAllowed;
024import java.lang.annotation.Annotation;
025
026/**
027 * Checks to see if a @{@link RolesAllowed} annotation is declared, and if so, performs
028 * a role check to see if the calling <code>Subject</code> is allowed to proceed.
029 *
030 * @since 2.0
031 */
032public class RolesAllowedAnnotationHandler extends AuthorizingAnnotationHandler {
033
034    /**
035     * Default no-argument constructor that ensures this handler looks for
036     * {@link org.apache.shiro.authz.annotation.RequiresRoles RequiresRoles} annotations.
037     */
038    public RolesAllowedAnnotationHandler() {
039        super(RolesAllowed.class);
040    }
041
042    /**
043     * Ensures that the calling <code>Subject</code> has one of the Annotation's specified roles, and if not, throws an
044     * <code>AuthorizingException</code> indicating that access is denied.
045     *
046     * @param a the RolesAllowed annotation to use to check for one or more roles
047     * @throws org.apache.shiro.authz.AuthorizationException if the calling <code>Subject</code> does not have the role
048     *                                                       necessary to proceed.
049     */
050    @Override
051    public void assertAuthorized(Annotation a) throws AuthorizationException {
052        if (!(a instanceof RolesAllowed)) {
053            return;
054        }
055
056        RolesAllowed raAnnotation = (RolesAllowed) a;
057        String[] roles = raAnnotation.value();
058
059        if (roles.length == 1) {
060            getSubject().checkRole(roles[0]);
061            return;
062        }
063
064        // Logical OR
065
066        // Avoid processing exceptions unnecessarily - "delay" throwing the exception by calling hasRole first
067        boolean hasAtLeastOneRole = false;
068        for (String role : roles) {
069            if (getSubject().hasRole(role)) {
070                hasAtLeastOneRole = true;
071            }
072        }
073        // Cause the exception if none of the role match, note that the exception message will be a bit misleading
074        if (!hasAtLeastOneRole) {
075            getSubject().checkRole(roles[0]);
076        }
077    }
078}