org.springframework.security.web.authentication.session.SessionFixationProtectionStrategy Maven / Gradle / Ivy
/*
* Copyright 2002-2013 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.web.authentication.session;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
/**
* The default implementation of {@link SessionAuthenticationStrategy} when using <
* Servlet 3.1.
*
* Creates a new session for the newly authenticated user if they already have a session
* (as a defence against session-fixation protection attacks), and copies their session
* attributes across to the new session. The copying of the attributes can be disabled by
* setting {@code migrateSessionAttributes} to {@code false} (note that even in this case,
* internal Spring Security attributes will still be migrated to the new session).
*
* This approach will only be effective if your servlet container always assigns a new
* session Id when a session is invalidated and a new session created by calling
* {@link HttpServletRequest#getSession()}.
*
*
Issues with {@code HttpSessionBindingListener}
*
* The migration of existing attributes to the newly-created session may cause problems if
* any of the objects implement the {@code HttpSessionBindingListener} interface in a way
* which makes assumptions about the life-cycle of the object. An example is the use of
* Spring session-scoped beans, where the initial removal of the bean from the session
* will cause the {@code DisposableBean} interface to be invoked, in the assumption that
* the bean is no longer required.
*
* We'd recommend that you take account of this when designing your application and do not
* store attributes which may not function correctly when they are removed and then placed
* back in the session. Alternatively, you should customize the
* {@code SessionAuthenticationStrategy} to deal with the issue in an application-specific
* way.
*
* @author Luke Taylor
* @since 3.0
*/
public class SessionFixationProtectionStrategy extends
AbstractSessionFixationProtectionStrategy {
/**
* Indicates that the session attributes of an existing session should be migrated to
* the new session. Defaults to true.
*/
boolean migrateSessionAttributes = true;
/**
* Called to extract the existing attributes from the session, prior to invalidating
* it. If {@code migrateAttributes} is set to {@code false}, only Spring Security
* attributes will be retained. All application attributes will be discarded.
*
* You can override this method to control exactly what is transferred to the new
* session.
*
* @param session the session from which the attributes should be extracted
* @return the map of session attributes which should be transferred to the new
* session
*/
protected Map extractAttributes(HttpSession session) {
return createMigratedAttributeMap(session);
}
@Override
final HttpSession applySessionFixation(HttpServletRequest request) {
HttpSession session = request.getSession();
String originalSessionId = session.getId();
if (logger.isDebugEnabled()) {
logger.debug("Invalidating session with Id '" + originalSessionId + "' "
+ (migrateSessionAttributes ? "and" : "without")
+ " migrating attributes.");
}
Map attributesToMigrate = extractAttributes(session);
session.invalidate();
session = request.getSession(true); // we now have a new session
if (logger.isDebugEnabled()) {
logger.debug("Started new session: " + session.getId());
}
transferAttributes(attributesToMigrate, session);
return session;
}
/**
* @param attributes the attributes which were extracted from the original session by
* {@code extractAttributes}
* @param newSession the newly created session
*/
void transferAttributes(Map attributes, HttpSession newSession) {
if (attributes != null) {
for (Map.Entry entry : attributes.entrySet()) {
newSession.setAttribute(entry.getKey(), entry.getValue());
}
}
}
@SuppressWarnings("unchecked")
private HashMap createMigratedAttributeMap(HttpSession session) {
HashMap attributesToMigrate = new HashMap<>();
Enumeration enumer = session.getAttributeNames();
while (enumer.hasMoreElements()) {
String key = (String) enumer.nextElement();
if (!migrateSessionAttributes && !key.startsWith("SPRING_SECURITY_")) {
// Only retain Spring Security attributes
continue;
}
attributesToMigrate.put(key, session.getAttribute(key));
}
return attributesToMigrate;
}
/**
* Defines whether attributes should be migrated to a new session or not. Has no
* effect if you override the {@code extractAttributes} method.
*
* Attributes used by Spring Security (to store cached requests, for example) will
* still be retained by default, even if you set this value to {@code false}.
*
* @param migrateSessionAttributes whether the attributes from the session should be
* transferred to the new, authenticated session.
*/
public void setMigrateSessionAttributes(boolean migrateSessionAttributes) {
this.migrateSessionAttributes = migrateSessionAttributes;
}
}