/*
* Copyright 2002-2016 the original author or authors.
*
* 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.springframework.security.config.method;
import java.lang.reflect.Method;
import java.util.*;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.aspectj.weaver.tools.PointcutExpression;
import org.aspectj.weaver.tools.PointcutParser;
import org.aspectj.weaver.tools.PointcutPrimitive;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.security.access.ConfigAttribute;
import org.springframework.security.access.intercept.aopalliance.MethodSecurityMetadataSourceAdvisor;
import org.springframework.security.access.method.MapBasedMethodSecurityMetadataSource;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
/**
* Parses AspectJ pointcut expressions, registering methods that match the pointcut with a
* traditional {@link MapBasedMethodSecurityMetadataSource}.
*
* <p>
* This class provides a convenient way of declaring a list of pointcuts, and then having
* every method of every bean defined in the Spring application context compared with
* those pointcuts. Where a match is found, the matching method will be registered with
* the {@link MapBasedMethodSecurityMetadataSource}.
* <p>
* It is very important to understand that only the <b>first</b> pointcut that matches a
* given method will be taken as authoritative for that method. This is why pointcuts
* should be provided as a <tt>LinkedHashMap</tt>, because their order is very important.
* <p>
* Note also that only beans defined in the Spring application context will be examined by
* this class.
* <p>
* Because this class registers method security metadata with
* {@link MapBasedMethodSecurityMetadataSource}, normal Spring Security capabilities such
* as {@link MethodSecurityMetadataSourceAdvisor} can be used. It does not matter the fact
* the method metadata was originally obtained from an AspectJ pointcut expression
* evaluation.
*
* @author Ben Alex
* @since 2.0
*/
final class ProtectPointcutPostProcessor implements BeanPostProcessor {
private static final Log logger = LogFactory
.getLog(ProtectPointcutPostProcessor.class);
private final Map<String, List<ConfigAttribute>> pointcutMap = new LinkedHashMap<String, List<ConfigAttribute>>();
private final MapBasedMethodSecurityMetadataSource mapBasedMethodSecurityMetadataSource;
private final Set<PointcutExpression> pointCutExpressions = new LinkedHashSet<PointcutExpression>();
private final PointcutParser parser;
private final Set<String> processedBeans = new HashSet<String>();
public ProtectPointcutPostProcessor(
MapBasedMethodSecurityMetadataSource mapBasedMethodSecurityMetadataSource) {
Assert.notNull(mapBasedMethodSecurityMetadataSource,
"MapBasedMethodSecurityMetadataSource to populate is required");
this.mapBasedMethodSecurityMetadataSource = mapBasedMethodSecurityMetadataSource;
// Set up AspectJ pointcut expression parser
Set<PointcutPrimitive> supportedPrimitives = new HashSet<PointcutPrimitive>(3);
supportedPrimitives.add(PointcutPrimitive.EXECUTION);
supportedPrimitives.add(PointcutPrimitive.ARGS);
supportedPrimitives.add(PointcutPrimitive.REFERENCE);
// supportedPrimitives.add(PointcutPrimitive.THIS);
// supportedPrimitives.add(PointcutPrimitive.TARGET);
// supportedPrimitives.add(PointcutPrimitive.WITHIN);
// supportedPrimitives.add(PointcutPrimitive.AT_ANNOTATION);
// supportedPrimitives.add(PointcutPrimitive.AT_WITHIN);
// supportedPrimitives.add(PointcutPrimitive.AT_ARGS);
// supportedPrimitives.add(PointcutPrimitive.AT_TARGET);
parser = PointcutParser
.getPointcutParserSupportingSpecifiedPrimitivesAndUsingContextClassloaderForResolution(supportedPrimitives);
}
public Object postProcessAfterInitialization(Object bean, String beanName)
throws BeansException {
return bean;
}
public Object postProcessBeforeInitialization(Object bean, String beanName)
throws BeansException {
if (processedBeans.contains(beanName)) {
// We already have the metadata for this bean
return bean;
}
synchronized (processedBeans) {
// check again synchronized this time
if (processedBeans.contains(beanName)) {
return bean;
}
// Obtain methods for the present bean
Method[] methods;
try {
methods = bean.getClass().getMethods();
}
catch (Exception e) {
throw new IllegalStateException(e.getMessage());
}
// Check to see if any of those methods are compatible with our pointcut
// expressions
for (Method method : methods) {
for (PointcutExpression expression : pointCutExpressions) {
// Try for the bean class directly
if (attemptMatch(bean.getClass(), method, expression, beanName)) {
// We've found the first expression that matches this method, so
// move onto the next method now
break; // the "while" loop, not the "for" loop
}
}
}
processedBeans.add(beanName);
}
return bean;
}
private boolean attemptMatch(Class<?> targetClass, Method method,
PointcutExpression expression, String beanName) {
// Determine if the presented AspectJ pointcut expression matches this method
boolean matches = expression.matchesMethodExecution(method).alwaysMatches();
// Handle accordingly
if (matches) {
List<ConfigAttribute> attr = pointcutMap.get(expression
.getPointcutExpression());
if (logger.isDebugEnabled()) {
logger.debug("AspectJ pointcut expression '"
+ expression.getPointcutExpression() + "' matches target class '"
+ targetClass.getName() + "' (bean ID '" + beanName
+ "') for method '" + method
+ "'; registering security configuration attribute '" + attr
+ "'");
}
mapBasedMethodSecurityMetadataSource.addSecureMethod(targetClass, method,
attr);
}
return matches;
}
public void setPointcutMap(Map<String, List<ConfigAttribute>> map) {
Assert.notEmpty(map, "configAttributes cannot be empty");
for (String expression : map.keySet()) {
List<ConfigAttribute> value = map.get(expression);
addPointcut(expression, value);
}
}
private void addPointcut(String pointcutExpression, List<ConfigAttribute> definition) {
Assert.hasText(pointcutExpression, "An AspectJ pointcut expression is required");
Assert.notNull(definition, "A List of ConfigAttributes is required");
pointcutExpression = replaceBooleanOperators(pointcutExpression);
pointcutMap.put(pointcutExpression, definition);
// Parse the presented AspectJ pointcut expression and add it to the cache
pointCutExpressions.add(parser.parsePointcutExpression(pointcutExpression));
if (logger.isDebugEnabled()) {
logger.debug("AspectJ pointcut expression '" + pointcutExpression
+ "' registered for security configuration attribute '" + definition
+ "'");
}
}
/**
* @see org.springframework.aop.aspectj.AspectJExpressionPointcut#replaceBooleanOperators
*/
private String replaceBooleanOperators(String pcExpr) {
pcExpr = StringUtils.replace(pcExpr, " and ", " && ");
pcExpr = StringUtils.replace(pcExpr, " or ", " || ");
pcExpr = StringUtils.replace(pcExpr, " not ", " ! ");
return pcExpr;
}
}