/*
* 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.springframework.security.web.access.intercept;
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import org.springframework.security.access.SecurityMetadataSource;
import org.springframework.security.access.intercept.AbstractSecurityInterceptor;
import org.springframework.security.access.intercept.InterceptorStatusToken;
import org.springframework.security.web.FilterInvocation;
/**
* Performs security handling of HTTP resources via a filter implementation.
* <p>
* The <code>SecurityMetadataSource</code> required by this security interceptor is of
* type {@link FilterInvocationSecurityMetadataSource}.
* <p>
* Refer to {@link AbstractSecurityInterceptor} for details on the workflow.
* </p>
*
* @author Ben Alex
* @author Rob Winch
*/
public class FilterSecurityInterceptor extends AbstractSecurityInterceptor implements
Filter {
// ~ Static fields/initializers
// =====================================================================================
private static final String FILTER_APPLIED = "__spring_security_filterSecurityInterceptor_filterApplied";
// ~ Instance fields
// ================================================================================================
private FilterInvocationSecurityMetadataSource securityMetadataSource;
private boolean observeOncePerRequest = true;
// ~ Methods
// ========================================================================================================
/**
* Not used (we rely on IoC container lifecycle services instead)
*
* @param arg0 ignored
*
* @throws ServletException never thrown
*/
public void init(FilterConfig arg0) throws ServletException {
}
/**
* Not used (we rely on IoC container lifecycle services instead)
*/
public void destroy() {
}
/**
* Method that is actually called by the filter chain. Simply delegates to the
* {@link #invoke(FilterInvocation)} method.
*
* @param request the servlet request
* @param response the servlet response
* @param chain the filter chain
*
* @throws IOException if the filter chain fails
* @throws ServletException if the filter chain fails
*/
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
FilterInvocation fi = new FilterInvocation(request, response, chain);
invoke(fi);
}
public FilterInvocationSecurityMetadataSource getSecurityMetadataSource() {
return this.securityMetadataSource;
}
public SecurityMetadataSource obtainSecurityMetadataSource() {
return this.securityMetadataSource;
}
public void setSecurityMetadataSource(FilterInvocationSecurityMetadataSource newSource) {
this.securityMetadataSource = newSource;
}
public Class<?> getSecureObjectClass() {
return FilterInvocation.class;
}
public void invoke(FilterInvocation fi) throws IOException, ServletException {
if ((fi.getRequest() != null)
&& (fi.getRequest().getAttribute(FILTER_APPLIED) != null)
&& observeOncePerRequest) {
// filter already applied to this request and user wants us to observe
// once-per-request handling, so don't re-do security checking
fi.getChain().doFilter(fi.getRequest(), fi.getResponse());
}
else {
// first time this request being called, so perform security checking
if (fi.getRequest() != null) {
fi.getRequest().setAttribute(FILTER_APPLIED, Boolean.TRUE);
}
InterceptorStatusToken token = super.beforeInvocation(fi);
try {
fi.getChain().doFilter(fi.getRequest(), fi.getResponse());
}
finally {
super.finallyInvocation(token);
}
super.afterInvocation(token, null);
}
}
/**
* Indicates whether once-per-request handling will be observed. By default this is
* <code>true</code>, meaning the <code>FilterSecurityInterceptor</code> will only
* execute once-per-request. Sometimes users may wish it to execute more than once per
* request, such as when JSP forwards are being used and filter security is desired on
* each included fragment of the HTTP request.
*
* @return <code>true</code> (the default) if once-per-request is honoured, otherwise
* <code>false</code> if <code>FilterSecurityInterceptor</code> will enforce
* authorizations for each and every fragment of the HTTP request.
*/
public boolean isObserveOncePerRequest() {
return observeOncePerRequest;
}
public void setObserveOncePerRequest(boolean observeOncePerRequest) {
this.observeOncePerRequest = observeOncePerRequest;
}
}