jdk/src/jdk.crypto.pkcs11/share/classes/sun/security/pkcs11/SessionManager.java
changeset 42939 e5d5f0f2d40d
parent 42938 c0b3077af726
parent 42767 8ea2f3d10b8c
child 42940 0d1409532a41
--- a/jdk/src/jdk.crypto.pkcs11/share/classes/sun/security/pkcs11/SessionManager.java	Tue Dec 06 14:54:11 2016 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,296 +0,0 @@
-/*
- * Copyright (c) 2003, 2016, 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.util.*;
-
-import java.security.ProviderException;
-
-import sun.security.util.Debug;
-
-import sun.security.pkcs11.wrapper.*;
-import static sun.security.pkcs11.wrapper.PKCS11Constants.*;
-
-import java.util.concurrent.LinkedBlockingQueue;
-import java.util.concurrent.atomic.AtomicInteger;
-
-/**
- * Session manager. There is one session manager object per PKCS#11
- * provider. It allows code to checkout a session, release it
- * back to the pool, or force it to be closed.
- *
- * The session manager pools sessions to minimize the number of
- * C_OpenSession() and C_CloseSession() that have to be made. It
- * maintains two pools: one for "object" sessions and one for
- * "operation" sessions.
- *
- * The reason for this separation is how PKCS#11 deals with session objects.
- * It defines that when a session is closed, all objects created within
- * that session are destroyed. In other words, we may never close a session
- * while a Key created it in is still in use. We would like to keep the
- * number of such sessions low. Note that we occasionally want to explicitly
- * close a session, see P11Signature.
- *
- * NOTE that sessions obtained from this class SHOULD be returned using
- * either releaseSession() or closeSession() using a finally block when
- * not needed anymore. Otherwise, they will be left for cleanup via the
- * PhantomReference mechanism when GC kicks in, but it's best not to rely
- * on that since GC may not run timely enough since the native PKCS11 library
- * is also consuming memory.
- *
- * Note that sessions are automatically closed when they are not used for a
- * period of time, see Session.
- *
- * @author  Andreas Sterbenz
- * @since   1.5
- */
-final class SessionManager {
-
-    private final static int DEFAULT_MAX_SESSIONS = 32;
-
-    private final static Debug debug = Debug.getInstance("pkcs11");
-
-    // token instance
-    private final Token token;
-
-    // maximum number of sessions to open with this token
-    private final int maxSessions;
-
-    // total number of active sessions
-    private AtomicInteger activeSessions = new AtomicInteger();
-
-    // pool of available object sessions
-    private final Pool objSessions;
-
-    // pool of available operation sessions
-    private final Pool opSessions;
-
-    // maximum number of active sessions during this invocation, for debugging
-    private int maxActiveSessions;
-    private Object maxActiveSessionsLock;
-
-    // flags to use in the C_OpenSession() call
-    private final long openSessionFlags;
-
-    SessionManager(Token token) {
-        long n;
-        if (token.isWriteProtected()) {
-            openSessionFlags = CKF_SERIAL_SESSION;
-            n = token.tokenInfo.ulMaxSessionCount;
-        } else {
-            openSessionFlags = CKF_SERIAL_SESSION | CKF_RW_SESSION;
-            n = token.tokenInfo.ulMaxRwSessionCount;
-        }
-        if (n == CK_EFFECTIVELY_INFINITE) {
-            n = Integer.MAX_VALUE;
-        } else if ((n == CK_UNAVAILABLE_INFORMATION) || (n < 0)) {
-            // choose an arbitrary concrete value
-            n = DEFAULT_MAX_SESSIONS;
-        }
-        maxSessions = (int)Math.min(n, Integer.MAX_VALUE);
-        this.token = token;
-        this.objSessions = new Pool(this, true);
-        this.opSessions = new Pool(this, false);
-        if (debug != null) {
-            maxActiveSessionsLock = new Object();
-        }
-    }
-
-    // returns whether only a fairly low number of sessions are
-    // supported by this token.
-    boolean lowMaxSessions() {
-        return (maxSessions <= DEFAULT_MAX_SESSIONS);
-    }
-
-    Session getObjSession() throws PKCS11Exception {
-        Session session = objSessions.poll();
-        if (session != null) {
-            return ensureValid(session);
-        }
-        session = opSessions.poll();
-        if (session != null) {
-            return ensureValid(session);
-        }
-        session = openSession();
-        return ensureValid(session);
-    }
-
-    Session getOpSession() throws PKCS11Exception {
-        Session session = opSessions.poll();
-        if (session != null) {
-            return ensureValid(session);
-        }
-        // create a new session rather than re-using an obj session
-        // that avoids potential expensive cancels() for Signatures & RSACipher
-        if (maxSessions == Integer.MAX_VALUE ||
-                activeSessions.get() < maxSessions) {
-            session = openSession();
-            return ensureValid(session);
-        }
-        session = objSessions.poll();
-        if (session != null) {
-            return ensureValid(session);
-        }
-        throw new ProviderException("Could not obtain session");
-    }
-
-    private Session ensureValid(Session session) {
-        session.id();
-        return session;
-    }
-
-    Session killSession(Session session) {
-        if ((session == null) || (token.isValid() == false)) {
-            return null;
-        }
-        if (debug != null) {
-            String location = new Exception().getStackTrace()[2].toString();
-            System.out.println("Killing session (" + location + ") active: "
-                + activeSessions.get());
-        }
-        closeSession(session);
-        return null;
-    }
-
-    Session releaseSession(Session session) {
-        if ((session == null) || (token.isValid() == false)) {
-            return null;
-        }
-
-        if (session.hasObjects()) {
-            objSessions.release(session);
-        } else {
-            opSessions.release(session);
-        }
-        return null;
-    }
-
-    void demoteObjSession(Session session) {
-        if (token.isValid() == false) {
-            return;
-        }
-        if (debug != null) {
-            System.out.println("Demoting session, active: " +
-                activeSessions.get());
-        }
-        boolean present = objSessions.remove(session);
-        if (present == false) {
-            // session is currently in use
-            // will be added to correct pool on release, nothing to do now
-            return;
-        }
-        opSessions.release(session);
-    }
-
-    private Session openSession() throws PKCS11Exception {
-        if ((maxSessions != Integer.MAX_VALUE) &&
-                (activeSessions.get() >= maxSessions)) {
-            throw new ProviderException("No more sessions available");
-        }
-
-        long id = token.p11.C_OpenSession
-                    (token.provider.slotID, openSessionFlags, null, null);
-        Session session = new Session(token, id);
-        activeSessions.incrementAndGet();
-        if (debug != null) {
-            synchronized(maxActiveSessionsLock) {
-                if (activeSessions.get() > maxActiveSessions) {
-                    maxActiveSessions = activeSessions.get();
-                    if (maxActiveSessions % 10 == 0) {
-                        System.out.println("Open sessions: " + maxActiveSessions);
-                    }
-                }
-            }
-        }
-        return session;
-    }
-
-    private void closeSession(Session session) {
-        session.close();
-        activeSessions.decrementAndGet();
-    }
-
-    public static final class Pool {
-
-        private final SessionManager mgr;
-        private final AbstractQueue<Session> pool;
-        private final int SESSION_MAX = 5;
-
-        // Object session pools can contain unlimited sessions.
-        // Operation session pools are limited and enforced by the queue.
-        Pool(SessionManager mgr, boolean obj) {
-            this.mgr = mgr;
-            if (obj) {
-                pool = new LinkedBlockingQueue<Session>();
-            } else {
-                pool = new LinkedBlockingQueue<Session>(SESSION_MAX);
-            }
-        }
-
-        boolean remove(Session session) {
-            return pool.remove(session);
-        }
-
-        Session poll() {
-            return pool.poll();
-        }
-
-        void release(Session session) {
-            // Object session pools never return false, only Operation ones
-            if (!pool.offer(session)) {
-                mgr.closeSession(session);
-                free();
-            }
-        }
-
-        // Free any old operation session if this queue is full
-        void free() {
-            int n = SESSION_MAX;
-            int i = 0;
-            Session oldestSession;
-            long time = System.currentTimeMillis();
-            // Check if the session head is too old and continue through pool
-            // until only one is left.
-            do {
-                oldestSession = pool.peek();
-                if (oldestSession == null || oldestSession.isLive(time) ||
-                        !pool.remove(oldestSession)) {
-                    break;
-                }
-
-                i++;
-                mgr.closeSession(oldestSession);
-            } while ((n - i) > 1);
-
-            if (debug != null) {
-                System.out.println("Closing " + i + " idle sessions, active: "
-                        + mgr.activeSessions);
-            }
-        }
-
-    }
-
-}