org.apache.catalina.core.ApplicationFilterFactory Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.catalina.core;
import javax.servlet.DispatcherType;
import javax.servlet.Servlet;
import javax.servlet.ServletRequest;
import org.apache.catalina.Globals;
import org.apache.catalina.Wrapper;
import org.apache.catalina.connector.Request;
import org.apache.tomcat.util.descriptor.web.FilterMap;
/**
* Factory for the creation and caching of Filters and creation
* of Filter Chains.
*
* @author Greg Murray
* @author Remy Maucherat
*/
public final class ApplicationFilterFactory {
private ApplicationFilterFactory() {
// Prevent instance creation. This is a utility class.
}
/**
* Construct a FilterChain implementation that will wrap the execution of
* the specified servlet instance.
*
* @param request The servlet request we are processing
* @param wrapper The wrapper managing the servlet instance
* @param servlet The servlet instance to be wrapped
*
* @return The configured FilterChain instance or null if none is to be
* executed.
*/
public static ApplicationFilterChain createFilterChain(ServletRequest request,
Wrapper wrapper, Servlet servlet) {
// If there is no servlet to execute, return null
if (servlet == null)
return null;
// Create and initialize a filter chain object
ApplicationFilterChain filterChain = null;
if (request instanceof Request) {
Request req = (Request) request;
if (Globals.IS_SECURITY_ENABLED) {
// Security: Do not recycle
filterChain = new ApplicationFilterChain();
} else {
filterChain = (ApplicationFilterChain) req.getFilterChain();
if (filterChain == null) {
filterChain = new ApplicationFilterChain();
req.setFilterChain(filterChain);
}
}
} else {
// Request dispatcher in use
filterChain = new ApplicationFilterChain();
}
filterChain.setServlet(servlet);
filterChain.setServletSupportsAsync(wrapper.isAsyncSupported());
// Acquire the filter mappings for this Context
StandardContext context = (StandardContext) wrapper.getParent();
FilterMap filterMaps[] = context.findFilterMaps();
// If there are no filter mappings, we are done
if ((filterMaps == null) || (filterMaps.length == 0))
return filterChain;
// Acquire the information we will need to match filter mappings
DispatcherType dispatcher =
(DispatcherType) request.getAttribute(Globals.DISPATCHER_TYPE_ATTR);
String requestPath = null;
Object attribute = request.getAttribute(Globals.DISPATCHER_REQUEST_PATH_ATTR);
if (attribute != null){
requestPath = attribute.toString();
}
String servletName = wrapper.getName();
// Add the relevant path-mapped filters to this filter chain
for (int i = 0; i < filterMaps.length; i++) {
if (!matchDispatcher(filterMaps[i] ,dispatcher)) {
continue;
}
if (!matchFiltersURL(filterMaps[i], requestPath))
continue;
ApplicationFilterConfig filterConfig = (ApplicationFilterConfig)
context.findFilterConfig(filterMaps[i].getFilterName());
if (filterConfig == null) {
// FIXME - log configuration problem
continue;
}
filterChain.addFilter(filterConfig);
}
// Add filters that match on servlet name second
for (int i = 0; i < filterMaps.length; i++) {
if (!matchDispatcher(filterMaps[i] ,dispatcher)) {
continue;
}
if (!matchFiltersServlet(filterMaps[i], servletName))
continue;
ApplicationFilterConfig filterConfig = (ApplicationFilterConfig)
context.findFilterConfig(filterMaps[i].getFilterName());
if (filterConfig == null) {
// FIXME - log configuration problem
continue;
}
filterChain.addFilter(filterConfig);
}
// Return the completed filter chain
return filterChain;
}
// -------------------------------------------------------- Private Methods
/**
* Return true if the context-relative request path
* matches the requirements of the specified filter mapping;
* otherwise, return false.
*
* @param filterMap Filter mapping being checked
* @param requestPath Context-relative request path of this request
*/
private static boolean matchFiltersURL(FilterMap filterMap, String requestPath) {
// Check the specific "*" special URL pattern, which also matches
// named dispatches
if (filterMap.getMatchAllUrlPatterns())
return true;
if (requestPath == null)
return false;
// Match on context relative request path
String[] testPaths = filterMap.getURLPatterns();
for (int i = 0; i < testPaths.length; i++) {
if (matchFiltersURL(testPaths[i], requestPath)) {
return true;
}
}
// No match
return false;
}
/**
* Return true if the context-relative request path
* matches the requirements of the specified filter mapping;
* otherwise, return false.
*
* @param testPath URL mapping being checked
* @param requestPath Context-relative request path of this request
*/
private static boolean matchFiltersURL(String testPath, String requestPath) {
if (testPath == null)
return false;
// Case 1 - Exact Match
if (testPath.equals(requestPath))
return true;
// Case 2 - Path Match ("/.../*")
if (testPath.equals("/*"))
return true;
if (testPath.endsWith("/*")) {
if (testPath.regionMatches(0, requestPath, 0,
testPath.length() - 2)) {
if (requestPath.length() == (testPath.length() - 2)) {
return true;
} else if ('/' == requestPath.charAt(testPath.length() - 2)) {
return true;
}
}
return false;
}
// Case 3 - Extension Match
if (testPath.startsWith("*.")) {
int slash = requestPath.lastIndexOf('/');
int period = requestPath.lastIndexOf('.');
if ((slash >= 0) && (period > slash)
&& (period != requestPath.length() - 1)
&& ((requestPath.length() - period)
== (testPath.length() - 1))) {
return testPath.regionMatches(2, requestPath, period + 1,
testPath.length() - 2);
}
}
// Case 4 - "Default" Match
return false; // NOTE - Not relevant for selecting filters
}
/**
* Return true if the specified servlet name matches
* the requirements of the specified filter mapping; otherwise
* return false.
*
* @param filterMap Filter mapping being checked
* @param servletName Servlet name being checked
*/
private static boolean matchFiltersServlet(FilterMap filterMap,
String servletName) {
if (servletName == null) {
return false;
}
// Check the specific "*" special servlet name
else if (filterMap.getMatchAllServletNames()) {
return true;
} else {
String[] servletNames = filterMap.getServletNames();
for (int i = 0; i < servletNames.length; i++) {
if (servletName.equals(servletNames[i])) {
return true;
}
}
return false;
}
}
/**
* Convenience method which returns true if the dispatcher type
* matches the dispatcher types specified in the FilterMap
*/
private static boolean matchDispatcher(FilterMap filterMap, DispatcherType type) {
switch (type) {
case FORWARD :
if ((filterMap.getDispatcherMapping() & FilterMap.FORWARD) != 0) {
return true;
}
break;
case INCLUDE :
if ((filterMap.getDispatcherMapping() & FilterMap.INCLUDE) != 0) {
return true;
}
break;
case REQUEST :
if ((filterMap.getDispatcherMapping() & FilterMap.REQUEST) != 0) {
return true;
}
break;
case ERROR :
if ((filterMap.getDispatcherMapping() & FilterMap.ERROR) != 0) {
return true;
}
break;
case ASYNC :
if ((filterMap.getDispatcherMapping() & FilterMap.ASYNC) != 0) {
return true;
}
break;
}
return false;
}
}