/*
* Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.security.pkcs11;
import java.lang.ref.*;
import java.util.*;
import java.util.concurrent.atomic.AtomicInteger;
import java.security.*;
import sun.security.pkcs11.wrapper.*;
/**
* A session object. Sessions are obtained via the SessionManager,
* see there for details. Most code will only ever need one method in
* this class, the id() method to obtain the session id.
*
* @author Andreas Sterbenz
* @since 1.5
*/
final class Session implements Comparable<Session> {
// time after which to close idle sessions, in milliseconds (3 minutes)
private final static long MAX_IDLE_TIME = 3 * 60 * 1000;
// token instance
final Token token;
// session id
private final long id;
// number of objects created within this session
private final AtomicInteger createdObjects;
// time this session was last used
// not synchronized/volatile for performance, so may be unreliable
// this could lead to idle sessions being closed early, but that is harmless
private long lastAccess;
private final SessionRef sessionRef;
Session(Token token, long id) {
this.token = token;
this.id = id;
createdObjects = new AtomicInteger();
id();
sessionRef = new SessionRef(this, id, token);
}
public int compareTo(Session other) {
if (this.lastAccess == other.lastAccess) {
return 0;
} else {
return (this.lastAccess < other.lastAccess) ? -1 : 1;
}
}
boolean isLive(long currentTime) {
return currentTime - lastAccess < MAX_IDLE_TIME;
}
long idInternal() {
return id;
}
long id() {
if (token.isPresent(this.id) == false) {
throw new ProviderException("Token has been removed");
}
lastAccess = System.currentTimeMillis();
return id;
}
void addObject() {
int n = createdObjects.incrementAndGet();
// XXX update statistics in session manager if n == 1
}
void removeObject() {
int n = createdObjects.decrementAndGet();
if (n == 0) {
token.sessionManager.demoteObjSession(this);
} else if (n < 0) {
throw new ProviderException("Internal error: objects created " + n);
}
}
boolean hasObjects() {
return createdObjects.get() != 0;
}
void close() {
if (hasObjects()) {
throw new ProviderException(
"Internal error: close session with active objects");
}
sessionRef.dispose();
}
}
/*
* NOTE: Use PhantomReference here and not WeakReference
* otherwise the sessions maybe closed before other objects
* which are still being finalized.
*/
final class SessionRef extends PhantomReference<Session>
implements Comparable<SessionRef> {
private static ReferenceQueue<Session> refQueue =
new ReferenceQueue<Session>();
private static Set<SessionRef> refList =
Collections.synchronizedSortedSet(new TreeSet<SessionRef>());
static ReferenceQueue<Session> referenceQueue() {
return refQueue;
}
static int totalCount() {
return refList.size();
}
private static void drainRefQueueBounded() {
while (true) {
SessionRef next = (SessionRef) refQueue.poll();
if (next == null) break;
next.dispose();
}
}
// handle to the native session
private long id;
private Token token;
SessionRef(Session session, long id, Token token) {
super(session, refQueue);
this.id = id;
this.token = token;
refList.add(this);
// TBD: run at some interval and not every time?
drainRefQueueBounded();
}
void dispose() {
refList.remove(this);
try {
if (token.isPresent(id)) {
token.p11.C_CloseSession(id);
}
} catch (PKCS11Exception e1) {
// ignore
} catch (ProviderException e2) {
// ignore
} finally {
this.clear();
}
}
public int compareTo(SessionRef other) {
if (this.id == other.id) {
return 0;
} else {
return (this.id < other.id) ? -1 : 1;
}
}
}