/*
 * Copyright 1996-2008 Sun Microsystems, Inc.  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.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

package sun.security.ssl;

import java.io.*;
import java.net.*;
import java.security.GeneralSecurityException;
import java.security.AccessController;
import java.security.AccessControlContext;
import java.security.PrivilegedAction;
import java.util.*;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.ReentrantLock;

import javax.crypto.BadPaddingException;

import javax.net.ssl.*;

import com.sun.net.ssl.internal.ssl.X509ExtendedTrustManager;

/**
 * Implementation of an SSL socket.  This is a normal connection type
 * socket, implementing SSL over some lower level socket, such as TCP.
 * Because it is layered over some lower level socket, it MUST override
 * all default socket methods.
 *
 * <P> This API offers a non-traditional option for establishing SSL
 * connections.  You may first establish the connection directly, then pass
 * that connection to the SSL socket constructor with a flag saying which
 * role should be taken in the handshake protocol.  (The two ends of the
 * connection must not choose the same role!)  This allows setup of SSL
 * proxying or tunneling, and also allows the kind of "role reversal"
 * that is required for most FTP data transfers.
 *
 * @see javax.net.ssl.SSLSocket
 * @see SSLServerSocket
 *
 * @author David Brownell
 */
final public class SSLSocketImpl extends BaseSSLSocketImpl {

    /*
     * ERROR HANDLING GUIDELINES
     * (which exceptions to throw and catch and which not to throw and catch)
     *
     * . if there is an IOException (SocketException) when accessing the
     *   underlying Socket, pass it through
     *
     * . do not throw IOExceptions, throw SSLExceptions (or a subclass)
     *
     * . for internal errors (things that indicate a bug in JSSE or a
     *   grossly misconfigured J2RE), throw either an SSLException or
     *   a RuntimeException at your convenience.
     *
     * . handshaking code (Handshaker or HandshakeMessage) should generally
     *   pass through exceptions, but can handle them if they know what to
     *   do.
     *
     * . exception chaining should be used for all new code. If you happen
     *   to touch old code that does not use chaining, you should change it.
     *
     * . there is a top level exception handler that sits at all entry
     *   points from application code to SSLSocket read/write code. It
     *   makes sure that all errors are handled (see handleException()).
     *
     * . JSSE internal code should generally not call close(), call
     *   closeInternal().
     */

    /*
     * There's a state machine associated with each connection, which
     * among other roles serves to negotiate session changes.
     *
     * - START with constructor, until the TCP connection's around.
     * - HANDSHAKE picks session parameters before allowing traffic.
     *          There are many substates due to sequencing requirements
     *          for handshake messages.
     * - DATA may be transmitted.
     * - RENEGOTIATE state allows concurrent data and handshaking
     *          traffic ("same" substates as HANDSHAKE), and terminates
     *          in selection of new session (and connection) parameters
     * - ERROR state immediately precedes abortive disconnect.
     * - SENT_CLOSE sent a close_notify to the peer. For layered,
     *          non-autoclose socket, must now read close_notify
     *          from peer before closing the connection. For nonlayered or
     *          non-autoclose socket, close connection and go onto
     *          cs_CLOSED state.
     * - CLOSED after sending close_notify alert, & socket is closed.
     *          SSL connection objects are not reused.
     * - APP_CLOSED once the application calls close(). Then it behaves like
     *          a closed socket, e.g.. getInputStream() throws an Exception.
     *
     * State affects what SSL record types may legally be sent:
     *
     * - Handshake ... only in HANDSHAKE and RENEGOTIATE states
     * - App Data ... only in DATA and RENEGOTIATE states
     * - Alert ... in HANDSHAKE, DATA, RENEGOTIATE
     *
     * Re what may be received:  same as what may be sent, except that
     * HandshakeRequest handshaking messages can come from servers even
     * in the application data state, to request entry to RENEGOTIATE.
     *
     * The state machine within HANDSHAKE and RENEGOTIATE states controls
     * the pending session, not the connection state, until the change
     * cipher spec and "Finished" handshake messages are processed and
     * make the "new" session become the current one.
     *
     * NOTE: details of the SMs always need to be nailed down better.
     * The text above illustrates the core ideas.
     *
     *                +---->-------+------>--------->-------+
     *                |            |                        |
     *     <-----<    ^            ^  <-----<               v
     *START>----->HANDSHAKE>----->DATA>----->RENEGOTIATE  SENT_CLOSE
     *                v            v               v        |   |
     *                |            |               |        |   v
     *                +------------+---------------+        v ERROR
     *                |                                     |   |
     *                v                                     |   |
     *               ERROR>------>----->CLOSED<--------<----+-- +
     *                                     |
     *                                     v
     *                                 APP_CLOSED
     *
     * ALSO, note that the the purpose of handshaking (renegotiation is
     * included) is to assign a different, and perhaps new, session to
     * the connection.  The SSLv3 spec is a bit confusing on that new
     * protocol feature.
     */
    private static final int    cs_START = 0;
    private static final int    cs_HANDSHAKE = 1;
    private static final int    cs_DATA = 2;
    private static final int    cs_RENEGOTIATE = 3;
    private static final int    cs_ERROR = 4;
    private static final int   cs_SENT_CLOSE = 5;
    private static final int    cs_CLOSED = 6;
    private static final int    cs_APP_CLOSED = 7;

    /*
     * Client authentication be off, requested, or required.
     *
     * Migrated to SSLEngineImpl:
     *    clauth_none/cl_auth_requested/clauth_required
     */

    /*
     * Drives the protocol state machine.
     */
    private int                 connectionState;

    /*
     * Flag indicating if the next record we receive MUST be a Finished
     * message. Temporarily set during the handshake to ensure that
     * a change cipher spec message is followed by a finished message.
     */
    private boolean             expectingFinished;

    /*
     * For improved diagnostics, we detail connection closure
     * If the socket is closed (connectionState >= cs_ERROR),
     * closeReason != null indicates if the socket was closed
     * because of an error or because or normal shutdown.
     */
    private SSLException        closeReason;

    /*
     * Per-connection private state that doesn't change when the
     * session is changed.
     */
    private byte                doClientAuth;
    private boolean             roleIsServer;
    private CipherSuiteList     enabledCipherSuites;
    private boolean             enableSessionCreation = true;
    private String              host;
    private boolean             autoClose = true;
    private AccessControlContext acc;

    // hostname identification algorithm, the hostname identification is
    // disabled by default.
    private String              identificationAlg = null;

    /*
     * READ ME * READ ME * READ ME * READ ME * READ ME * READ ME *
     * IMPORTANT STUFF TO UNDERSTANDING THE SYNCHRONIZATION ISSUES.
     * READ ME * READ ME * READ ME * READ ME * READ ME * READ ME *
     *
     * There are several locks here.
     *
     * The primary lock is the per-instance lock used by
     * synchronized(this) and the synchronized methods.  It controls all
     * access to things such as the connection state and variables which
     * affect handshaking.  If we are inside a synchronized method, we
     * can access the state directly, otherwise, we must use the
     * synchronized equivalents.
     *
     * The handshakeLock is used to ensure that only one thread performs
     * the *complete initial* handshake.  If someone is handshaking, any
     * stray application or startHandshake() requests who find the
     * connection state is cs_HANDSHAKE will stall on handshakeLock
     * until handshaking is done.  Once the handshake is done, we either
     * succeeded or failed, but we can never go back to the cs_HANDSHAKE
     * or cs_START state again.
     *
     * Note that the read/write() calls here in SSLSocketImpl are not
     * obviously synchronized.  In fact, it's very nonintuitive, and
     * requires careful examination of code paths.  Grab some coffee,
     * and be careful with any code changes.
     *
     * There can be only three threads active at a time in the I/O
     * subsection of this class.
     *    1.  startHandshake
     *    2.  AppInputStream
     *    3.  AppOutputStream
     * One thread could call startHandshake().
     * AppInputStream/AppOutputStream read() and write() calls are each
     * synchronized on 'this' in their respective classes, so only one
     * app. thread will be doing a SSLSocketImpl.read() or .write()'s at
     * a time.
     *
     * If handshaking is required (state cs_HANDSHAKE), and
     * getConnectionState() for some/all threads returns cs_HANDSHAKE,
     * only one can grab the handshakeLock, and the rest will stall
     * either on getConnectionState(), or on the handshakeLock if they
     * happen to successfully race through the getConnectionState().
     *
     * If a writer is doing the initial handshaking, it must create a
     * temporary reader to read the responses from the other side.  As a
     * side-effect, the writer's reader will have priority over any
     * other reader.  However, the writer's reader is not allowed to
     * consume any application data.  When handshakeLock is finally
     * released, we either have a cs_DATA connection, or a
     * cs_CLOSED/cs_ERROR socket.
     *
     * The writeLock is held while writing on a socket connection and
     * also to protect the MAC and cipher for their direction.  The
     * writeLock is package private for Handshaker which holds it while
     * writing the ChangeCipherSpec message.
     *
     * To avoid the problem of a thread trying to change operational
     * modes on a socket while handshaking is going on, we synchronize
     * on 'this'.  If handshaking has not started yet, we tell the
     * handshaker to change its mode.  If handshaking has started,
     * we simply store that request until the next pending session
     * is created, at which time the new handshaker's state is set.
     *
     * The readLock is held during readRecord(), which is responsible
     * for reading an InputRecord, decrypting it, and processing it.
     * The readLock ensures that these three steps are done atomically
     * and that once started, no other thread can block on InputRecord.read.
     * This is necessary so that processing of close_notify alerts
     * from the peer are handled properly.
     */
    private Object              handshakeLock;
    ReentrantLock               writeLock;
    private Object              readLock;

    private InputRecord         inrec;

    /*
     * Crypto state that's reinitialized when the session changes.
     */
    private MAC                 readMAC, writeMAC;
    private CipherBox           readCipher, writeCipher;
    // NOTE: compression state would be saved here

    /*
     * The authentication context holds all information used to establish
     * who this end of the connection is (certificate chains, private keys,
     * etc) and who is trusted (e.g. as CAs or websites).
     */
    private SSLContextImpl      sslContext;

    /*
     * This connection is one of (potentially) many associated with
     * any given session.  The output of the handshake protocol is a
     * new session ... although all the protocol description talks
     * about changing the cipher spec (and it does change), in fact
     * that's incidental since it's done by changing everything that
     * is associated with a session at the same time.  (TLS/IETF may
     * change that to add client authentication w/o new key exchg.)
     */
    private SSLSessionImpl      sess;
    private Handshaker          handshaker;

    /*
     * If anyone wants to get notified about handshake completions,
     * they'll show up on this list.
     */
    private HashMap<HandshakeCompletedListener, AccessControlContext>
                                                        handshakeListeners;

    /*
     * Reuse the same internal input/output streams.
     */
    private InputStream         sockInput;
    private OutputStream        sockOutput;

    /*
     * These input and output streams block their data in SSL records,
     * and usually arrange integrity and privacy protection for those
     * records.  The guts of the SSL protocol are wrapped up in these
     * streams, and in the handshaking that establishes the details of
     * that integrity and privacy protection.
     */
    private AppInputStream      input;
    private AppOutputStream     output;

    /*
     * The protocols we support are SSL Version 3.0) and
     * TLS (version 3.1).
     * In addition we support a pseudo protocol called
     * SSLv2Hello which when set will result in an SSL v2 Hello
     * being sent with SSLv3 or TLSv1 version info.
     */
    private ProtocolList enabledProtocols;

    /*
     * The SSL version associated with this connection.
     */
    private ProtocolVersion     protocolVersion = ProtocolVersion.DEFAULT;

    /* Class and subclass dynamic debugging support */
    private static final Debug debug = Debug.getInstance("ssl");

    //
    // CONSTRUCTORS AND INITIALIZATION CODE
    //

    /**
     * Constructs an SSL connection to a named host at a specified port,
     * using the authentication context provided.  This endpoint acts as
     * the client, and may rejoin an existing SSL session if appropriate.
     *
     * @param context authentication context to use
     * @param host name of the host with which to connect
     * @param port number of the server's port
     */
    SSLSocketImpl(SSLContextImpl context, String host, int port)
            throws IOException, UnknownHostException {
        super();
        this.host = host;
        init(context, false);
        SocketAddress socketAddress = new InetSocketAddress(host, port);
        connect(socketAddress, 0);
    }

    /**
     * Constructs an SSL connection to a server at a specified address.
     * and TCP port, using the authentication context provided.  This
     * endpoint acts as the client, and may rejoin an existing SSL session
     * if appropriate.
     *
     * @param context authentication context to use
     * @param address the server's host
     * @param port its port
     */
    SSLSocketImpl(SSLContextImpl context, InetAddress host, int port)
            throws IOException {
        super();
        init(context, false);
        SocketAddress socketAddress = new InetSocketAddress(host, port);
        connect(socketAddress, 0);
    }

    /**
     * Constructs an SSL connection to a named host at a specified port,
     * using the authentication context provided.  This endpoint acts as
     * the client, and may rejoin an existing SSL session if appropriate.
     *
     * @param context authentication context to use
     * @param host name of the host with which to connect
     * @param port number of the server's port
     * @param localAddr the local address the socket is bound to
     * @param localPort the local port the socket is bound to
     */
    SSLSocketImpl(SSLContextImpl context, String host, int port,
            InetAddress localAddr, int localPort)
            throws IOException, UnknownHostException {
        super();
        this.host = host;
        init(context, false);
        bind(new InetSocketAddress(localAddr, localPort));
        SocketAddress socketAddress = new InetSocketAddress(host, port);
        connect(socketAddress, 0);
    }

    /**
     * Constructs an SSL connection to a server at a specified address.
     * and TCP port, using the authentication context provided.  This
     * endpoint acts as the client, and may rejoin an existing SSL session
     * if appropriate.
     *
     * @param context authentication context to use
     * @param address the server's host
     * @param port its port
     * @param localAddr the local address the socket is bound to
     * @param localPort the local port the socket is bound to
     */
    SSLSocketImpl(SSLContextImpl context, InetAddress host, int port,
            InetAddress localAddr, int localPort)
            throws IOException {
        super();
        init(context, false);
        bind(new InetSocketAddress(localAddr, localPort));
        SocketAddress socketAddress = new InetSocketAddress(host, port);
        connect(socketAddress, 0);
    }

    /*
     * Package-private constructor used ONLY by SSLServerSocket.  The
     * java.net package accepts the TCP connection after this call is
     * made.  This just initializes handshake state to use "server mode",
     * giving control over the use of SSL client authentication.
     */
    SSLSocketImpl(SSLContextImpl context, boolean serverMode,
            CipherSuiteList suites, byte clientAuth,
            boolean sessionCreation, ProtocolList protocols)
            throws IOException {
        super();
        doClientAuth = clientAuth;
        enableSessionCreation = sessionCreation;
        init(context, serverMode);

        /*
         * Override what was picked out for us.
         */
        enabledCipherSuites = suites;
        enabledProtocols = protocols;
    }

    /**
     * Package-private constructor used to instantiate an unconnected
     * socket. The java.net package will connect it, either when the
     * connect() call is made by the application.  This instance is
     * meant to set handshake state to use "client mode".
     */
    SSLSocketImpl(SSLContextImpl context) {
        super();
        init(context, false);
    }

    /**
     * Layer SSL traffic over an existing connection, rather than creating
     * a new connection.  The existing connection may be used only for SSL
     * traffic (using this SSLSocket) until the SSLSocket.close() call
     * returns. However, if a protocol error is detected, that existing
     * connection is automatically closed.
     *
     * <P> This particular constructor always uses the socket in the
     * role of an SSL client. It may be useful in cases which start
     * using SSL after some initial data transfers, for example in some
     * SSL tunneling applications or as part of some kinds of application
     * protocols which negotiate use of a SSL based security.
     *
     * @param sock the existing connection
     * @param context the authentication context to use
     */
    SSLSocketImpl(SSLContextImpl context, Socket sock, String host,
            int port, boolean autoClose) throws IOException {
        super(sock);
        // We always layer over a connected socket
        if (!sock.isConnected()) {
            throw new SocketException("Underlying socket is not connected");
        }
        this.host = host;
        init(context, false);
        this.autoClose = autoClose;
        doneConnect();
    }

    /**
     * Initializes the client socket.
     */
    private void init(SSLContextImpl context, boolean isServer) {
        sslContext = context;
        sess = SSLSessionImpl.nullSession;

        /*
         * role is as specified, state is START until after
         * the low level connection's established.
         */
        roleIsServer = isServer;
        connectionState = cs_START;

        /*
         * default read and write side cipher and MAC support
         *
         * Note:  compression support would go here too
         */
        readCipher = CipherBox.NULL;
        readMAC = MAC.NULL;
        writeCipher = CipherBox.NULL;
        writeMAC = MAC.NULL;

        enabledCipherSuites = CipherSuiteList.getDefault();
        enabledProtocols = ProtocolList.getDefault();
        handshakeLock = new Object();
        writeLock = new ReentrantLock();
        readLock = new Object();
        inrec = null;

        // save the acc
        acc = AccessController.getContext();

        input = new AppInputStream(this);
        output = new AppOutputStream(this);
    }

    /**
     * Connects this socket to the server with a specified timeout
     * value.
     *
     * This method is either called on an unconnected SSLSocketImpl by the
     * application, or it is called in the constructor of a regular
     * SSLSocketImpl. If we are layering on top on another socket, then
     * this method should not be called, because we assume that the
     * underlying socket is already connected by the time it is passed to
     * us.
     *
     * @param   endpoint the <code>SocketAddress</code>
     * @param   timeout  the timeout value to be used, 0 is no timeout
     * @throws  IOException if an error occurs during the connection
     * @throws  SocketTimeoutException if timeout expires before connecting
     */
    public void connect(SocketAddress endpoint, int timeout)
            throws IOException {

        if (self != this) {
            throw new SocketException("Already connected");
        }

        if (!(endpoint instanceof InetSocketAddress)) {
            throw new SocketException(
                                  "Cannot handle non-Inet socket addresses.");
        }

        super.connect(endpoint, timeout);
        doneConnect();
    }

    /**
     * Initialize the handshaker and socket streams.
     *
     * Called by connect, the layered constructor, and SSLServerSocket.
     */
    void doneConnect() throws IOException {
        /*
         * Save the input and output streams.  May be done only after
         * java.net actually connects using the socket "self", else
         * we get some pretty bizarre failure modes.
         */
        if (self == this) {
            sockInput = super.getInputStream();
            sockOutput = super.getOutputStream();
        } else {
            sockInput = self.getInputStream();
            sockOutput = self.getOutputStream();
        }

        /*
         * Move to handshaking state, with pending session initialized
         * to defaults and the appropriate kind of handshaker set up.
         */
        initHandshaker();
    }

    synchronized private int getConnectionState() {
        return connectionState;
    }

    synchronized private void setConnectionState(int state) {
        connectionState = state;
    }

    AccessControlContext getAcc() {
        return acc;
    }

    //
    // READING AND WRITING RECORDS
    //

    /*
     * Record Output. Application data can't be sent until the first
     * handshake establishes a session.
     *
     * NOTE:  we let empty records be written as a hook to force some
     * TCP-level activity, notably handshaking, to occur.
     */
    void writeRecord(OutputRecord r) throws IOException {
        /*
         * The loop is in case of HANDSHAKE --> ERROR transitions, etc
         */
    loop:
        while (r.contentType() == Record.ct_application_data) {
            /*
             * Not all states support passing application data.  We
             * synchronize access to the connection state, so that
             * synchronous handshakes can complete cleanly.
             */
            switch (getConnectionState()) {

            /*
             * We've deferred the initial handshaking till just now,
             * when presumably a thread's decided it's OK to block for
             * longish periods of time for I/O purposes (as well as
             * configured the cipher suites it wants to use).
             */
            case cs_HANDSHAKE:
                performInitialHandshake();
                break;

            case cs_DATA:
            case cs_RENEGOTIATE:
                break loop;

            case cs_ERROR:
                fatal(Alerts.alert_close_notify,
                    "error while writing to socket");
                break; // dummy

            case cs_SENT_CLOSE:
            case cs_CLOSED:
            case cs_APP_CLOSED:
                // we should never get here (check in AppOutputStream)
                // this is just a fallback
                if (closeReason != null) {
                    throw closeReason;
                } else {
                    throw new SocketException("Socket closed");
                }

            /*
             * Else something's goofy in this state machine's use.
             */
            default:
                throw new SSLProtocolException("State error, send app data");
            }
        }

        //
        // Don't bother to really write empty records.  We went this
        // far to drive the handshake machinery, for correctness; not
        // writing empty records improves performance by cutting CPU
        // time and network resource usage.  However, some protocol
        // implementations are fragile and don't like to see empty
        // records, so this also increases robustness.
        //
        if (!r.isEmpty()) {

            // If the record is a close notify alert, we need to honor
            // socket option SO_LINGER. Note that we will try to send
            // the close notify even if the SO_LINGER set to zero.
            if (r.isAlert(Alerts.alert_close_notify) && getSoLinger() >= 0) {

                // keep and clear the current thread interruption status.
                boolean interrupted = Thread.interrupted();
                try {
                    if (writeLock.tryLock(getSoLinger(), TimeUnit.SECONDS)) {
                        try {
                            writeRecordInternal(r);
                        } finally {
                            writeLock.unlock();
                        }
                    } else {
                        SSLException ssle = new SSLException(
                                "SO_LINGER timeout," +
                                " close_notify message cannot be sent.");

                        // For layered, non-autoclose sockets, we are not
                        // able to bring them into a usable state, so we
                        // treat it as fatal error.
                        if (self != this && !autoClose) {
                            // Note that the alert description is
                            // specified as -1, so no message will be send
                            // to peer anymore.
                            fatal((byte)(-1), ssle);
                        } else if ((debug != null) && Debug.isOn("ssl")) {
                            System.out.println(threadName() +
                                ", received Exception: " + ssle);
                        }

                        // RFC2246 requires that the session becomes
                        // unresumable if any connection is terminated
                        // without proper close_notify messages with
                        // level equal to warning.
                        //
                        // RFC4346 no longer requires that a session not be
                        // resumed if failure to properly close a connection.
                        //
                        // We choose to make the session unresumable if
                        // failed to send the close_notify message.
                        //
                        sess.invalidate();
                    }
                } catch (InterruptedException ie) {
                    // keep interrupted status
                    interrupted = true;
                }

                // restore the interrupted status
                if (interrupted) {
                    Thread.currentThread().interrupt();
                }
            } else {
                writeLock.lock();
                try {
                    writeRecordInternal(r);
                } finally {
                    writeLock.unlock();
                }
            }
        }
    }

    private void writeRecordInternal(OutputRecord r) throws IOException {
        // r.compress(c);
        r.addMAC(writeMAC);
        r.encrypt(writeCipher);
        r.write(sockOutput);
    }

    /*
     * Read an application data record.  Alerts and handshake
     * messages are handled directly.
     */
    void readDataRecord(InputRecord r) throws IOException {
        if (getConnectionState() == cs_HANDSHAKE) {
            performInitialHandshake();
        }
        readRecord(r, true);
    }

    /*
     * Clear the pipeline of records from the peer, optionally returning
     * application data.   Caller is responsible for knowing that it's
     * possible to do this kind of clearing, if they don't want app
     * data -- e.g. since it's the initial SSL handshake.
     *
     * Don't synchronize (this) during a blocking read() since it
     * protects data which is accessed on the write side as well.
     */
    private void readRecord(InputRecord r, boolean needAppData)
            throws IOException {
        int state;

        // readLock protects reading and processing of an InputRecord.
        // It keeps the reading from sockInput and processing of the record
        // atomic so that no two threads can be blocked on the
        // read from the same input stream at the same time.
        // This is required for example when a reader thread is
        // blocked on the read and another thread is trying to
        // close the socket. For a non-autoclose, layered socket,
        // the thread performing the close needs to read the close_notify.
        //
        // Use readLock instead of 'this' for locking because
        // 'this' also protects data accessed during writing.
      synchronized (readLock) {
        /*
         * Read and handle records ... return application data
         * ONLY if it's needed.
         */

        while (((state = getConnectionState()) != cs_CLOSED) &&
                (state != cs_ERROR) && (state != cs_APP_CLOSED)) {
            /*
             * Read a record ... maybe emitting an alert if we get a
             * comprehensible but unsupported "hello" message during
             * format checking (e.g. V2).
             */
            try {
                r.setAppDataValid(false);
                r.read(sockInput, sockOutput);
            } catch (SSLProtocolException e) {
                try {
                    fatal(Alerts.alert_unexpected_message, e);
                } catch (IOException x) {
                    // discard this exception
                }
                throw e;
            } catch (EOFException eof) {
                boolean handshaking = (getConnectionState() <= cs_HANDSHAKE);
                boolean rethrow = requireCloseNotify || handshaking;
                if ((debug != null) && Debug.isOn("ssl")) {
                    System.out.println(threadName() +
                        ", received EOFException: "
                        + (rethrow ? "error" : "ignored"));
                }
                if (rethrow) {
                    SSLException e;
                    if (handshaking) {
                        e = new SSLHandshakeException
                            ("Remote host closed connection during handshake");
                    } else {
                        e = new SSLProtocolException
                            ("Remote host closed connection incorrectly");
                    }
                    e.initCause(eof);
                    throw e;
                } else {
                    // treat as if we had received a close_notify
                    closeInternal(false);
                    continue;
                }
            }

            /*
             * The basic SSLv3 record protection involves (optional)
             * encryption for privacy, and an integrity check ensuring
             * data origin authentication.  We do them both here, and
             * throw a fatal alert if the integrity check fails.
             */
            try {
                r.decrypt(readCipher);
            } catch (BadPaddingException e) {
                // RFC 2246 states that decryption_failed should be used
                // for this purpose. However, that allows certain attacks,
                // so we just send bad record MAC. We also need to make
                // sure to always check the MAC to avoid a timing attack
                // for the same issue. See paper by Vaudenay et al.
                r.checkMAC(readMAC);
                // use the same alert types as for MAC failure below
                byte alertType = (r.contentType() == Record.ct_handshake)
                                        ? Alerts.alert_handshake_failure
                                        : Alerts.alert_bad_record_mac;
                fatal(alertType, "Invalid padding", e);
            }
            if (!r.checkMAC(readMAC)) {
                if (r.contentType() == Record.ct_handshake) {
                    fatal(Alerts.alert_handshake_failure,
                        "bad handshake record MAC");
                } else {
                    fatal(Alerts.alert_bad_record_mac, "bad record MAC");
                }
            }

            // if (!r.decompress(c))
            //     fatal(Alerts.alert_decompression_failure,
            //         "decompression failure");

            /*
             * Process the record.
             */
            synchronized (this) {
              switch (r.contentType()) {
                case Record.ct_handshake:
                    /*
                     * Handshake messages always go to a pending session
                     * handshaker ... if there isn't one, create one.  This
                     * must work asynchronously, for renegotiation.
                     *
                     * NOTE that handshaking will either resume a session
                     * which was in the cache (and which might have other
                     * connections in it already), or else will start a new
                     * session (new keys exchanged) with just this connection
                     * in it.
                     */
                    initHandshaker();

                    /*
                     * process the handshake record ... may contain just
                     * a partial handshake message or multiple messages.
                     *
                     * The handshaker state machine will ensure that it's
                     * a finished message.
                     */
                    handshaker.process_record(r, expectingFinished);
                    expectingFinished = false;

                    if (handshaker.isDone()) {
                        sess = handshaker.getSession();
                        handshaker = null;
                        connectionState = cs_DATA;

                        //
                        // Tell folk about handshake completion, but do
                        // it in a separate thread.
                        //
                        if (handshakeListeners != null) {
                            HandshakeCompletedEvent event =
                                new HandshakeCompletedEvent(this, sess);

                            Thread t = new NotifyHandshakeThread(
                                handshakeListeners.entrySet(), event);
                            t.start();
                        }
                    }
                    if (needAppData || connectionState != cs_DATA) {
                        continue;
                    } else {
                        return;
                    }

                case Record.ct_application_data:
                    // Pass this right back up to the application.
                    if (connectionState != cs_DATA
                            && connectionState != cs_RENEGOTIATE
                            && connectionState != cs_SENT_CLOSE) {
                        throw new SSLProtocolException(
                            "Data received in non-data state: " +
                            connectionState);
                    }
                    if (expectingFinished) {
                        throw new SSLProtocolException
                                ("Expecting finished message, received data");
                    }
                    if (!needAppData) {
                        throw new SSLException("Discarding app data");
                    }

                    r.setAppDataValid(true);
                    return;

                case Record.ct_alert:
                    recvAlert(r);
                    continue;

                case Record.ct_change_cipher_spec:
                    if ((connectionState != cs_HANDSHAKE
                                && connectionState != cs_RENEGOTIATE)
                            || r.available() != 1
                            || r.read() != 1) {
                        fatal(Alerts.alert_unexpected_message,
                            "illegal change cipher spec msg, state = "
                            + connectionState);
                    }

                    //
                    // The first message after a change_cipher_spec
                    // record MUST be a "Finished" handshake record,
                    // else it's a protocol violation.  We force this
                    // to be checked by a minor tweak to the state
                    // machine.
                    //
                    changeReadCiphers();
                    // next message MUST be a finished message
                    expectingFinished = true;
                    continue;

                default:
                    //
                    // TLS requires that unrecognized records be ignored.
                    //
                    if (debug != null && Debug.isOn("ssl")) {
                        System.out.println(threadName() +
                            ", Received record type: "
                            + r.contentType());
                    }
                    continue;
              } // switch
            } // synchronized (this)
        }

        //
        // couldn't read, due to some kind of error
        //
        r.close();
        return;
      }  // synchronized (readLock)
    }

    //
    // HANDSHAKE RELATED CODE
    //

    /**
     * Return the AppInputStream. For use by Handshaker only.
     */
    AppInputStream getAppInputStream() {
        return input;
    }

    /**
     * Initialize and get the server handshaker. Used by SSLServerSocketImpl
     * for the ciphersuite availability test *only*.
     */
    ServerHandshaker getServerHandshaker() throws SSLException {
        initHandshaker();

        // The connection state would have been set to cs_HANDSHAKE during the
        // handshaking initializing, however the caller may not have the
        // the low level connection's established, which is not consistent with
        // the HANDSHAKE state. As if it is unconnected, we need to reset the
        // connection state to cs_START.
        if (!isConnected()) {
            connectionState = cs_START;
        }

        // Make sure that we get a ServerHandshaker.
        // This should never happen.
        if (!(handshaker instanceof ServerHandshaker)) {
            throw new SSLProtocolException("unexpected handshaker instance");
        }

        return (ServerHandshaker)handshaker;
    }

    /**
     * Initialize the handshaker object. This means:
     *
     *  . if a handshake is already in progress (state is cs_HANDSHAKE
     *    or cs_RENEGOTIATE), do nothing and return
     *
     *  . if the socket is already closed, throw an Exception (internal error)
     *
     *  . otherwise (cs_START or cs_DATA), create the appropriate handshaker
     *    object, initialize it, and advance the connection state (to
     *    cs_HANDSHAKE or cs_RENEGOTIATE, respectively).
     *
     * This method is called right after a new socket is created, when
     * starting renegotiation, or when changing client/ server mode of the
     * socket.
     */
    private void initHandshaker() {
        switch (connectionState) {

        //
        // Starting a new handshake.
        //
        case cs_START:
        case cs_DATA:
            break;

        //
        // We're already in the middle of a handshake.
        //
        case cs_HANDSHAKE:
        case cs_RENEGOTIATE:
            return;

        //
        // Anyone allowed to call this routine is required to
        // do so ONLY if the connection state is reasonable...
        //
        default:
            throw new IllegalStateException("Internal error");
        }

        // state is either cs_START or cs_DATA
        if (connectionState == cs_START) {
            connectionState = cs_HANDSHAKE;
        } else { // cs_DATA
            connectionState = cs_RENEGOTIATE;
        }
        if (roleIsServer) {
            handshaker = new ServerHandshaker
                        (this, sslContext, enabledProtocols, doClientAuth);
        } else {
            handshaker = new ClientHandshaker
                        (this, sslContext, enabledProtocols);
        }
        handshaker.enabledCipherSuites = enabledCipherSuites;
        handshaker.setEnableSessionCreation(enableSessionCreation);
        if (connectionState == cs_RENEGOTIATE) {
            // don't use SSLv2Hello when renegotiating
            handshaker.output.r.setHelloVersion(protocolVersion);
        }
    }

    /**
     * Synchronously perform the initial handshake.
     *
     * If the handshake is already in progress, this method blocks until it
     * is completed. If the initial handshake has already been completed,
     * it returns immediately.
     */
    private void performInitialHandshake() throws IOException {
        // use handshakeLock and the state check to make sure only
        // one thread performs the handshake
        synchronized (handshakeLock) {
            if (getConnectionState() == cs_HANDSHAKE) {
                /*
                 * All initial handshaking goes through this
                 * InputRecord until we have a valid SSL connection.
                 * Once initial handshaking is finished, AppInputStream's
                 * InputRecord can handle any future renegotiation.
                 *
                 * Keep this local so that it goes out of scope and is
                 * eventually GC'd.
                 */
                if (inrec == null) {
                    inrec = new InputRecord();

                    /*
                     * Grab the characteristics already assigned to
                     * AppInputStream's InputRecord.  Enable checking for
                     * SSLv2 hellos on this first handshake.
                     */
                    inrec.setHandshakeHash(input.r.getHandshakeHash());
                    inrec.setHelloVersion(input.r.getHelloVersion());
                    inrec.enableFormatChecks();
                }

                kickstartHandshake();
                readRecord(inrec, false);
                inrec = null;
            }
        }
    }

    /**
     * Starts an SSL handshake on this connection.
     */
    public void startHandshake() throws IOException {
        // start an ssl handshake that could be resumed from timeout exception
        startHandshake(true);
    }

    /**
     * Starts an ssl handshake on this connection.
     *
     * @param resumable indicates the handshake process is resumable from a
     *          certain exception. If <code>resumable</code>, the socket will
     *          be reserved for exceptions like timeout; otherwise, the socket
     *          will be closed, no further communications could be done.
     */
    private void startHandshake(boolean resumable) throws IOException {
        checkWrite();
        try {
            if (getConnectionState() == cs_HANDSHAKE) {
                // do initial handshake
                performInitialHandshake();
            } else {
                // start renegotiation
                kickstartHandshake();
            }
        } catch (Exception e) {
            // shutdown and rethrow (wrapped) exception as appropriate
            handleException(e, resumable);
        }
    }

    /**
     * Kickstart the handshake if it is not already in progress.
     * This means:
     *
     *  . if handshaking is already underway, do nothing and return
     *
     *  . if the socket is not connected or already closed, throw an
     *    Exception.
     *
     *  . otherwise, call initHandshake() to initialize the handshaker
     *    object and progress the state. Then, send the initial
     *    handshaking message if appropriate (always on clients and
     *    on servers when renegotiating).
     */
    private synchronized void kickstartHandshake() throws IOException {
        switch (connectionState) {

        case cs_HANDSHAKE:
            // handshaker already setup, proceed
            break;

        case cs_DATA:
            // initialize the handshaker, move to cs_RENEGOTIATE
            initHandshaker();
            break;

        case cs_RENEGOTIATE:
            // handshaking already in progress, return
            return;

        /*
         * The only way to get a socket in the state is when
         * you have an unconnected socket.
         */
        case cs_START:
            throw new SocketException(
                "handshaking attempted on unconnected socket");

        default:
            throw new SocketException("connection is closed");
        }

        //
        // Kickstart handshake state machine if we need to ...
        //
        // Note that handshaker.kickstart() writes the message
        // to its HandshakeOutStream, which calls back into
        // SSLSocketImpl.writeRecord() to send it.
        //
        if (!handshaker.started()) {
            if (handshaker instanceof ClientHandshaker) {
                // send client hello
                handshaker.kickstart();
            } else {
                if (connectionState == cs_HANDSHAKE) {
                    // initial handshake, no kickstart message to send
                } else {
                    // we want to renegotiate, send hello request
                    handshaker.kickstart();
                    // hello request is not included in the handshake
                    // hashes, reset them
                    handshaker.handshakeHash.reset();
                }
            }
        }
    }

    //
    // CLOSURE RELATED CALLS
    //

    /**
     * Return whether the socket has been explicitly closed by the application.
     */
    public boolean isClosed() {
        return getConnectionState() == cs_APP_CLOSED;
    }

    /**
     * Return whether we have reached end-of-file.
     *
     * If the socket is not connected, has been shutdown because of an error
     * or has been closed, throw an Exception.
     */
    boolean checkEOF() throws IOException {
        switch (getConnectionState()) {
        case cs_START:
            throw new SocketException("Socket is not connected");

        case cs_HANDSHAKE:
        case cs_DATA:
        case cs_RENEGOTIATE:
        case cs_SENT_CLOSE:
            return false;

        case cs_APP_CLOSED:
            throw new SocketException("Socket is closed");

        case cs_ERROR:
        case cs_CLOSED:
        default:
            // either closed because of error, or normal EOF
            if (closeReason == null) {
                return true;
            }
            IOException e = new SSLException
                        ("Connection has been shutdown: " + closeReason);
            e.initCause(closeReason);
            throw e;

        }
    }

    /**
     * Check if we can write data to this socket. If not, throw an IOException.
     */
    void checkWrite() throws IOException {
        if (checkEOF() || (getConnectionState() == cs_SENT_CLOSE)) {
            // we are at EOF, write must throw Exception
            throw new SocketException("Connection closed by remote host");
        }
    }

    protected void closeSocket() throws IOException {
        if ((debug != null) && Debug.isOn("ssl")) {
            System.out.println(threadName() + ", called closeSocket()");
        }
        if (self == this) {
            super.close();
        } else {
            self.close();
        }
    }

    /*
     * Closing the connection is tricky ... we can't officially close the
     * connection until we know the other end is ready to go away too,
     * and if ever the connection gets aborted we must forget session
     * state (it becomes invalid).
     */

    /**
     * Closes the SSL connection.  SSL includes an application level
     * shutdown handshake; you should close SSL sockets explicitly
     * rather than leaving it for finalization, so that your remote
     * peer does not experience a protocol error.
     */
    public void close() throws IOException {
        if ((debug != null) && Debug.isOn("ssl")) {
            System.out.println(threadName() + ", called close()");
        }
        closeInternal(true);  // caller is initiating close
        setConnectionState(cs_APP_CLOSED);
    }

    /**
     * Don't synchronize the whole method because waitForClose()
     * (which calls readRecord()) might be called.
     *
     * @param selfInitiated Indicates which party initiated the close.
     * If selfInitiated, this side is initiating a close; for layered and
     * non-autoclose socket, wait for close_notify response.
     * If !selfInitiated, peer sent close_notify; we reciprocate but
     * no need to wait for response.
     */
    private void closeInternal(boolean selfInitiated) throws IOException {
        if ((debug != null) && Debug.isOn("ssl")) {
            System.out.println(threadName() + ", called closeInternal("
                + selfInitiated + ")");
        }

        int state = getConnectionState();
        try {
            switch (state) {
            /*
             * java.net code sometimes closes sockets "early", when
             * we can't actually do I/O on them.
             */
            case cs_START:
                break;

            /*
             * If we're closing down due to error, we already sent (or else
             * received) the fatal alert ... no niceties, blow the connection
             * away as quickly as possible (even if we didn't allocate the
             * socket ourselves; it's unusable, regardless).
             */
            case cs_ERROR:
                closeSocket();
                break;

            /*
             * Sometimes close() gets called more than once.
             */
            case cs_CLOSED:
            case cs_APP_CLOSED:
                 break;

            /*
             * Otherwise we indicate clean termination.
             */
            // case cs_HANDSHAKE:
            // case cs_DATA:
            // case cs_RENEGOTIATE:
            // case cs_SENT_CLOSE:
            default:
                synchronized (this) {
                    if (((state = getConnectionState()) == cs_CLOSED) ||
                       (state == cs_ERROR) || (state == cs_APP_CLOSED)) {
                        return;  // connection was closed while we waited
                    }
                    if (state != cs_SENT_CLOSE) {
                        warning(Alerts.alert_close_notify);
                        connectionState = cs_SENT_CLOSE;
                    }
                }
                // If state was cs_SENT_CLOSE before, we don't do the actual
                // closing since it is already in progress.
                if (state == cs_SENT_CLOSE) {
                    if (debug != null && Debug.isOn("ssl")) {
                        System.out.println(threadName() +
                            ", close invoked again; state = " +
                            getConnectionState());
                    }
                    if (selfInitiated == false) {
                        // We were called because a close_notify message was
                        // received. This may be due to another thread calling
                        // read() or due to our call to waitForClose() below.
                        // In either case, just return.
                        return;
                    }
                    // Another thread explicitly called close(). We need to
                    // wait for the closing to complete before returning.
                    synchronized (this) {
                        while (connectionState < cs_CLOSED) {
                            try {
                                this.wait();
                            } catch (InterruptedException e) {
                                // ignore
                            }
                        }
                    }
                    if ((debug != null) && Debug.isOn("ssl")) {
                        System.out.println(threadName() +
                            ", after primary close; state = " +
                            getConnectionState());
                    }
                    return;
                }

                if (self == this) {
                    super.close();
                } else if (autoClose) {
                    self.close();
                } else if (selfInitiated) {
                    // layered && non-autoclose
                    // read close_notify alert to clear input stream
                    waitForClose(false);
                }

                // state will be set to cs_CLOSED in the finally block below

                break;
            }
        } finally {
            synchronized (this) {
                // Upon exit from this method, the state is always >= cs_CLOSED
                connectionState = (connectionState == cs_APP_CLOSED)
                                ? cs_APP_CLOSED : cs_CLOSED;
                // notify any threads waiting for the closing to finish
                this.notifyAll();
            }
        }
    }

    /**
     * Reads a close_notify or a fatal alert from the input stream.
     * Keep reading records until we get a close_notify or until
     * the connection is otherwise closed.  The close_notify or alert
     * might be read by another reader,
     * which will then process the close and set the connection state.
     */
    void waitForClose(boolean rethrow) throws IOException {
        if (debug != null && Debug.isOn("ssl")) {
            System.out.println(threadName() +
                ", waiting for close_notify or alert: state "
                + getConnectionState());
        }

        try {
            int state;

            while (((state = getConnectionState()) != cs_CLOSED) &&
                   (state != cs_ERROR) && (state != cs_APP_CLOSED)) {
                // create the InputRecord if it isn't intialized.
                if (inrec == null) {
                    inrec = new InputRecord();
                }

                // Ask for app data and then throw it away
                try {
                    readRecord(inrec, true);
                } catch (SocketTimeoutException e) {
                    // if time out, ignore the exception and continue
                }
            }
            inrec = null;
        } catch (IOException e) {
            if (debug != null && Debug.isOn("ssl")) {
                System.out.println(threadName() +
                    ", Exception while waiting for close " +e);
            }
            if (rethrow) {
                throw e; // pass exception up
            }
        }
    }

    //
    // EXCEPTION AND ALERT HANDLING
    //

    /**
     * Handle an exception. This method is called by top level exception
     * handlers (in read(), write()) to make sure we always shutdown the
     * connection correctly and do not pass runtime exception to the
     * application.
     */
    void handleException(Exception e) throws IOException {
        handleException(e, true);
    }

    /**
     * Handle an exception. This method is called by top level exception
     * handlers (in read(), write(), startHandshake()) to make sure we
     * always shutdown the connection correctly and do not pass runtime
     * exception to the application.
     *
     * This method never returns normally, it always throws an IOException.
     *
     * We first check if the socket has already been shutdown because of an
     * error. If so, we just rethrow the exception. If the socket has not
     * been shutdown, we sent a fatal alert and remember the exception.
     *
     * @param e the Exception
     * @param resumable indicates the caller process is resumable from the
     *          exception. If <code>resumable</code>, the socket will be
     *          reserved for exceptions like timeout; otherwise, the socket
     *          will be closed, no further communications could be done.
     */
    synchronized private void handleException(Exception e, boolean resumable)
        throws IOException {
        if ((debug != null) && Debug.isOn("ssl")) {
            System.out.println(threadName()
                        + ", handling exception: " + e.toString());
        }

        // don't close the Socket in case of timeouts or interrupts if
        // the process is resumable.
        if (e instanceof InterruptedIOException && resumable) {
            throw (IOException)e;
        }

        // if we've already shutdown because of an error,
        // there is nothing to do except rethrow the exception
        if (closeReason != null) {
            if (e instanceof IOException) { // includes SSLException
                throw (IOException)e;
            } else {
                // this is odd, not an IOException.
                // normally, this should not happen
                // if closeReason has been already been set
                throw Alerts.getSSLException(Alerts.alert_internal_error, e,
                                      "Unexpected exception");
            }
        }

        // need to perform error shutdown
        boolean isSSLException = (e instanceof SSLException);
        if ((isSSLException == false) && (e instanceof IOException)) {
            // IOException from the socket
            // this means the TCP connection is already dead
            // we call fatal just to set the error status
            try {
                fatal(Alerts.alert_unexpected_message, e);
            } catch (IOException ee) {
                // ignore (IOException wrapped in SSLException)
            }
            // rethrow original IOException
            throw (IOException)e;
        }

        // must be SSLException or RuntimeException
        byte alertType;
        if (isSSLException) {
            if (e instanceof SSLHandshakeException) {
                alertType = Alerts.alert_handshake_failure;
            } else {
                alertType = Alerts.alert_unexpected_message;
            }
        } else {
            alertType = Alerts.alert_internal_error;
        }
        fatal(alertType, e);
    }

    /*
     * Send a warning alert.
     */
    void warning(byte description) {
        sendAlert(Alerts.alert_warning, description);
    }

    synchronized void fatal(byte description, String diagnostic)
            throws IOException {
        fatal(description, diagnostic, null);
    }

    synchronized void fatal(byte description, Throwable cause)
            throws IOException {
        fatal(description, null, cause);
    }

    /*
     * Send a fatal alert, and throw an exception so that callers will
     * need to stand on their heads to accidentally continue processing.
     */
    synchronized void fatal(byte description, String diagnostic,
            Throwable cause) throws IOException {
        if ((input != null) && (input.r != null)) {
            input.r.close();
        }
        sess.invalidate();

        int oldState = connectionState;
        connectionState = cs_ERROR;

        /*
         * Has there been an error received yet?  If not, remember it.
         * By RFC 2246, we don't bother waiting for a response.
         * Fatal errors require immediate shutdown.
         */
        if (closeReason == null) {
            /*
             * Try to clear the kernel buffer to avoid TCP connection resets.
             */
            if (oldState == cs_HANDSHAKE) {
                sockInput.skip(sockInput.available());
            }

            // If the description equals -1, the alert won't be sent to peer.
            if (description != -1) {
                sendAlert(Alerts.alert_fatal, description);
            }
            if (cause instanceof SSLException) { // only true if != null
                closeReason = (SSLException)cause;
            } else {
                closeReason =
                    Alerts.getSSLException(description, cause, diagnostic);
            }
        }

        /*
         * Clean up our side.
         */
        closeSocket();
        connectionState = (oldState == cs_APP_CLOSED) ? cs_APP_CLOSED
                                                      : cs_CLOSED;
        throw closeReason;
    }

    /*
     * Process an incoming alert ... caller must already have synchronized
     * access to "this".
     */
    private void recvAlert(InputRecord r) throws IOException {
        byte level = (byte)r.read();
        byte description = (byte)r.read();
        if (description == -1) { // check for short message
            fatal(Alerts.alert_illegal_parameter, "Short alert message");
        }

        if (debug != null && (Debug.isOn("record") ||
                Debug.isOn("handshake"))) {
            synchronized (System.out) {
                System.out.print(threadName());
                System.out.print(", RECV " + protocolVersion + " ALERT:  ");
                if (level == Alerts.alert_fatal) {
                    System.out.print("fatal, ");
                } else if (level == Alerts.alert_warning) {
                    System.out.print("warning, ");
                } else {
                    System.out.print("<level " + (0x0ff & level) + ">, ");
                }
                System.out.println(Alerts.alertDescription(description));
            }
        }

        if (level == Alerts.alert_warning) {
            if (description == Alerts.alert_close_notify) {
                if (connectionState == cs_HANDSHAKE) {
                    fatal(Alerts.alert_unexpected_message,
                                "Received close_notify during handshake");
                } else {
                    closeInternal(false);  // reply to close
                }
            } else {

                //
                // The other legal warnings relate to certificates,
                // e.g. no_certificate, bad_certificate, etc; these
                // are important to the handshaking code, which can
                // also handle illegal protocol alerts if needed.
                //
                if (handshaker != null) {
                    handshaker.handshakeAlert(description);
                }
            }
        } else { // fatal or unknown level
            String reason = "Received fatal alert: "
                + Alerts.alertDescription(description);
            if (closeReason == null) {
                closeReason = Alerts.getSSLException(description, reason);
            }
            fatal(Alerts.alert_unexpected_message, reason);
        }
    }

    /*
     * Emit alerts.  Caller must have synchronized with "this".
     */
    private void sendAlert(byte level, byte description) {
        if (connectionState >= cs_SENT_CLOSE) {
            return;
        }

        OutputRecord r = new OutputRecord(Record.ct_alert);
        r.setVersion(protocolVersion);

        boolean useDebug = debug != null && Debug.isOn("ssl");
        if (useDebug) {
            synchronized (System.out) {
                System.out.print(threadName());
                System.out.print(", SEND " + protocolVersion + " ALERT:  ");
                if (level == Alerts.alert_fatal) {
                    System.out.print("fatal, ");
                } else if (level == Alerts.alert_warning) {
                    System.out.print("warning, ");
                } else {
                    System.out.print("<level = " + (0x0ff & level) + ">, ");
                }
                System.out.println("description = "
                        + Alerts.alertDescription(description));
            }
        }

        r.write(level);
        r.write(description);
        try {
            writeRecord(r);
        } catch (IOException e) {
            if (useDebug) {
                System.out.println(threadName() +
                    ", Exception sending alert: " + e);
            }
        }
    }

    //
    // VARIOUS OTHER METHODS
    //

    /*
     * When a connection finishes handshaking by enabling use of a newly
     * negotiated session, each end learns about it in two halves (read,
     * and write).  When both read and write ciphers have changed, and the
     * last handshake message has been read, the connection has joined
     * (rejoined) the new session.
     *
     * NOTE:  The SSLv3 spec is rather unclear on the concepts here.
     * Sessions don't change once they're established (including cipher
     * suite and master secret) but connections can join them (and leave
     * them).  They're created by handshaking, though sometime handshaking
     * causes connections to join up with pre-established sessions.
     */
    private void changeReadCiphers() throws SSLException {
        if (connectionState != cs_HANDSHAKE
                && connectionState != cs_RENEGOTIATE) {
            throw new SSLProtocolException(
                "State error, change cipher specs");
        }

        // ... create decompressor

        try {
            readCipher = handshaker.newReadCipher();
            readMAC = handshaker.newReadMAC();
        } catch (GeneralSecurityException e) {
            // "can't happen"
            throw (SSLException)new SSLException
                                ("Algorithm missing:  ").initCause(e);
        }
    }

    // used by Handshaker
    void changeWriteCiphers() throws SSLException {
        if (connectionState != cs_HANDSHAKE
                && connectionState != cs_RENEGOTIATE) {
            throw new SSLProtocolException(
                "State error, change cipher specs");
        }

        // ... create compressor

        try {
            writeCipher = handshaker.newWriteCipher();
            writeMAC = handshaker.newWriteMAC();
        } catch (GeneralSecurityException e) {
            // "can't happen"
            throw (SSLException)new SSLException
                                ("Algorithm missing:  ").initCause(e);
        }
    }

    /*
     * Updates the SSL version associated with this connection.
     * Called from Handshaker once it has determined the negotiated version.
     */
    synchronized void setVersion(ProtocolVersion protocolVersion) {
        this.protocolVersion = protocolVersion;
        output.r.setVersion(protocolVersion);
    }

    synchronized String getHost() {
        if (host == null) {
            host = getInetAddress().getHostName();
        }
        return host;
    }

    /**
     * Gets an input stream to read from the peer on the other side.
     * Data read from this stream was always integrity protected in
     * transit, and will usually have been confidentiality protected.
     */
    synchronized public InputStream getInputStream() throws IOException {
        if (isClosed()) {
            throw new SocketException("Socket is closed");
        }

        /*
         * Can't call isConnected() here, because the Handshakers
         * do some initialization before we actually connect.
         */
        if (connectionState == cs_START) {
            throw new SocketException("Socket is not connected");
        }

        return input;
    }

    /**
     * Gets an output stream to write to the peer on the other side.
     * Data written on this stream is always integrity protected, and
     * will usually be confidentiality protected.
     */
    synchronized public OutputStream getOutputStream() throws IOException {
        if (isClosed()) {
            throw new SocketException("Socket is closed");
        }

        /*
         * Can't call isConnected() here, because the Handshakers
         * do some initialization before we actually connect.
         */
        if (connectionState == cs_START) {
            throw new SocketException("Socket is not connected");
        }

        return output;
    }

    /**
     * Returns the the SSL Session in use by this connection.  These can
     * be long lived, and frequently correspond to an entire login session
     * for some user.
     */
    public SSLSession getSession() {
        /*
         * Force a synchronous handshake, if appropriate.
         */
        if (getConnectionState() == cs_HANDSHAKE) {
            try {
                // start handshaking, if failed, the connection will be closed.
                startHandshake(false);
            } catch (IOException e) {
                // handshake failed. log and return a nullSession
                if (debug != null && Debug.isOn("handshake")) {
                      System.out.println(threadName() +
                          ", IOException in getSession():  " + e);
                }
            }
        }
        synchronized (this) {
            return sess;
        }
    }

    /**
     * Controls whether new connections may cause creation of new SSL
     * sessions.
     *
     * As long as handshaking has not started, we can change
     * whether we enable session creations.  Otherwise,
     * we will need to wait for the next handshake.
     */
    synchronized public void setEnableSessionCreation(boolean flag) {
        enableSessionCreation = flag;

        if ((handshaker != null) && !handshaker.started()) {
            handshaker.setEnableSessionCreation(enableSessionCreation);
        }
    }

    /**
     * Returns true if new connections may cause creation of new SSL
     * sessions.
     */
    synchronized public boolean getEnableSessionCreation() {
        return enableSessionCreation;
    }

    /**
     * Sets the flag controlling whether a server mode socket
     * *REQUIRES* SSL client authentication.
     *
     * As long as handshaking has not started, we can change
     * whether client authentication is needed.  Otherwise,
     * we will need to wait for the next handshake.
     */
    synchronized public void setNeedClientAuth(boolean flag) {
        doClientAuth = (flag ?
            SSLEngineImpl.clauth_required : SSLEngineImpl.clauth_none);

        if ((handshaker != null) &&
                (handshaker instanceof ServerHandshaker) &&
                !handshaker.started()) {
            ((ServerHandshaker) handshaker).setClientAuth(doClientAuth);
        }
    }

    synchronized public boolean getNeedClientAuth() {
        return (doClientAuth == SSLEngineImpl.clauth_required);
    }

    /**
     * Sets the flag controlling whether a server mode socket
     * *REQUESTS* SSL client authentication.
     *
     * As long as handshaking has not started, we can change
     * whether client authentication is requested.  Otherwise,
     * we will need to wait for the next handshake.
     */
    synchronized public void setWantClientAuth(boolean flag) {
        doClientAuth = (flag ?
            SSLEngineImpl.clauth_requested : SSLEngineImpl.clauth_none);

        if ((handshaker != null) &&
                (handshaker instanceof ServerHandshaker) &&
                !handshaker.started()) {
            ((ServerHandshaker) handshaker).setClientAuth(doClientAuth);
        }
    }

    synchronized public boolean getWantClientAuth() {
        return (doClientAuth == SSLEngineImpl.clauth_requested);
    }

    /**
     * Sets the flag controlling whether the socket is in SSL
     * client or server mode.  Must be called before any SSL
     * traffic has started.
     */
    synchronized public void setUseClientMode(boolean flag) {
        switch (connectionState) {

        case cs_START:
            roleIsServer = !flag;
            break;

        case cs_HANDSHAKE:
            /*
             * If we have a handshaker, but haven't started
             * SSL traffic, we can throw away our current
             * handshaker, and start from scratch.  Don't
             * need to call doneConnect() again, we already
             * have the streams.
             */
            assert(handshaker != null);
            if (!handshaker.started()) {
                roleIsServer = !flag;
                connectionState = cs_START;
                initHandshaker();
                break;
            }

            // If handshake has started, that's an error.  Fall through...

        default:
            if (debug != null && Debug.isOn("ssl")) {
                System.out.println(threadName() +
                    ", setUseClientMode() invoked in state = " +
                    connectionState);
            }
            throw new IllegalArgumentException(
                "Cannot change mode after SSL traffic has started");
        }
    }

    synchronized public boolean getUseClientMode() {
        return !roleIsServer;
    }

    /**
     * Returns the names of the cipher suites which could be enabled for use
     * on an SSL connection.  Normally, only a subset of these will actually
     * be enabled by default, since this list may include cipher suites which
     * do not support the mutual authentication of servers and clients, or
     * which do not protect data confidentiality.  Servers may also need
     * certain kinds of certificates to use certain cipher suites.
     *
     * @return an array of cipher suite names
     */
    public String[] getSupportedCipherSuites() {
        CipherSuiteList.clearAvailableCache();
        return CipherSuiteList.getSupported().toStringArray();
    }

    /**
     * Controls which particular cipher suites are enabled for use on
     * this connection.  The cipher suites must have been listed by
     * getCipherSuites() as being supported.  Even if a suite has been
     * enabled, it might never be used if no peer supports it or the
     * requisite certificates (and private keys) are not available.
     *
     * @param suites Names of all the cipher suites to enable.
     */
    synchronized public void setEnabledCipherSuites(String[] suites) {
        enabledCipherSuites = new CipherSuiteList(suites);
        if ((handshaker != null) && !handshaker.started()) {
            handshaker.enabledCipherSuites = enabledCipherSuites;
        }
    }

    /**
     * Returns the names of the SSL cipher suites which are currently enabled
     * for use on this connection.  When an SSL socket is first created,
     * all enabled cipher suites <em>(a)</em> protect data confidentiality,
     * by traffic encryption, and <em>(b)</em> can mutually authenticate
     * both clients and servers.  Thus, in some environments, this value
     * might be empty.
     *
     * @return an array of cipher suite names
     */
    synchronized public String[] getEnabledCipherSuites() {
        return enabledCipherSuites.toStringArray();
    }

    /**
     * Returns the protocols that are supported by this implementation.
     * A subset of the supported protocols may be enabled for this connection
     * @ returns an array of protocol names.
     */
    public String[] getSupportedProtocols() {
        return ProtocolList.getSupported().toStringArray();
    }

    /**
     * Controls which protocols are enabled for use on
     * this connection.  The protocols must have been listed by
     * getSupportedProtocols() as being supported.
     *
     * @param protocols protocols to enable.
     * @exception IllegalArgumentException when one of the protocols
     *  named by the parameter is not supported.
     */
    synchronized public void setEnabledProtocols(String[] protocols) {
        enabledProtocols = new ProtocolList(protocols);
        if ((handshaker != null) && !handshaker.started()) {
            handshaker.setEnabledProtocols(enabledProtocols);
        }
    }

    synchronized public String[] getEnabledProtocols() {
        return enabledProtocols.toStringArray();
    }

    /**
     * Assigns the socket timeout.
     * @see java.net.Socket#setSoTimeout
     */
    public void setSoTimeout(int timeout) throws SocketException {
        if ((debug != null) && Debug.isOn("ssl")) {
            System.out.println(threadName() +
                ", setSoTimeout(" + timeout + ") called");
        }
        if (self == this) {
            super.setSoTimeout(timeout);
        } else {
            self.setSoTimeout(timeout);
        }
    }

    /**
     * Registers an event listener to receive notifications that an
     * SSL handshake has completed on this connection.
     */
    public synchronized void addHandshakeCompletedListener(
            HandshakeCompletedListener listener) {
        if (listener == null) {
            throw new IllegalArgumentException("listener is null");
        }
        if (handshakeListeners == null) {
            handshakeListeners = new
                HashMap<HandshakeCompletedListener, AccessControlContext>(4);
        }
        handshakeListeners.put(listener, AccessController.getContext());
    }

    /**
     * Removes a previously registered handshake completion listener.
     */
    public synchronized void removeHandshakeCompletedListener(
            HandshakeCompletedListener listener) {
        if (handshakeListeners == null) {
            throw new IllegalArgumentException("no listeners");
        }
        if (handshakeListeners.remove(listener) == null) {
            throw new IllegalArgumentException("listener not registered");
        }
        if (handshakeListeners.isEmpty()) {
            handshakeListeners = null;
        }
    }

    /**
     * Try to configure the endpoint identification algorithm of the socket.
     *
     * @param identificationAlgorithm the algorithm used to check the
     *        endpoint identity.
     * @return true if the identification algorithm configuration success.
     */
    synchronized public boolean trySetHostnameVerification(
        String identificationAlgorithm) {
        if (sslContext.getX509TrustManager() instanceof
                X509ExtendedTrustManager) {
            this.identificationAlg = identificationAlgorithm;
            return true;
        } else {
            return false;
        }
    }

    /**
     * Returns the endpoint identification algorithm of the socket.
     */
    synchronized public String getHostnameVerification() {
        return identificationAlg;
    }

    //
    // We allocate a separate thread to deliver handshake completion
    // events.  This ensures that the notifications don't block the
    // protocol state machine.
    //
    private static class NotifyHandshakeThread extends Thread {

        private Set<Map.Entry<HandshakeCompletedListener,AccessControlContext>>
                targets;        // who gets notified
        private HandshakeCompletedEvent event;          // the notification

        NotifyHandshakeThread(
            Set<Map.Entry<HandshakeCompletedListener,AccessControlContext>>
            entrySet, HandshakeCompletedEvent e) {

            super("HandshakeCompletedNotify-Thread");
            targets = entrySet;
            event = e;
        }

        public void run() {
            for (Map.Entry<HandshakeCompletedListener,AccessControlContext>
                entry : targets) {

                final HandshakeCompletedListener l = entry.getKey();
                AccessControlContext acc = entry.getValue();
                AccessController.doPrivileged(new PrivilegedAction<Void>() {
                    public Void run() {
                        l.handshakeCompleted(event);
                        return null;
                    }
                }, acc);
            }
        }
    }

    /**
     * Return the name of the current thread. Utility method.
     */
    private static String threadName() {
        return Thread.currentThread().getName();
    }

    /**
     * Returns a printable representation of this end of the connection.
     */
    public String toString() {
        StringBuffer retval = new StringBuffer(80);

        retval.append(Integer.toHexString(hashCode()));
        retval.append("[");
        retval.append(sess.getCipherSuite());
        retval.append(": ");

        if (self == this) {
            retval.append(super.toString());
        } else {
            retval.append(self.toString());
        }
        retval.append("]");

        return retval.toString();
    }
}

{'repo_name': 'GregBowyer/ManagedRuntimeInitiative', 'stars': '112', 'repo_language': 'Java', 'file_name': 'jar.1', 'mime_type': 'text/plain', 'hash': 3106349456267576020, 'source_dataset': 'data'}


@Library('cilium') _
pipeline {
    agent {
        label 'baremetal'
    }

    parameters {
        string(defaultValue: '${ghprbPullDescription}', name: 'ghprbPullDescription')
        string(defaultValue: '${ghprbActualCommit}', name: 'ghprbActualCommit')
        string(defaultValue: '${ghprbTriggerAuthorLoginMention}', name: 'ghprbTriggerAuthorLoginMention')
        string(defaultValue: '${ghprbPullAuthorLoginMention}', name: 'ghprbPullAuthorLoginMention')
        string(defaultValue: '${ghprbGhRepository}', name: 'ghprbGhRepository')
        string(defaultValue: '${ghprbPullLongDescription}', name: 'ghprbPullLongDescription')
        string(defaultValue: '${ghprbCredentialsId}', name: 'ghprbCredentialsId')
        string(defaultValue: '${ghprbTriggerAuthorLogin}', name: 'ghprbTriggerAuthorLogin')
        string(defaultValue: '${ghprbPullAuthorLogin}', name: 'ghprbPullAuthorLogin')
        string(defaultValue: '${ghprbTriggerAuthor}', name: 'ghprbTriggerAuthor')
        string(defaultValue: '${ghprbCommentBody}', name: 'ghprbCommentBody')
        string(defaultValue: '${ghprbPullTitle}', name: 'ghprbPullTitle')
        string(defaultValue: '${ghprbPullLink}', name: 'ghprbPullLink')
        string(defaultValue: '${ghprbAuthorRepoGitUrl}', name: 'ghprbAuthorRepoGitUrl')
        string(defaultValue: '${ghprbTargetBranch}', name: 'ghprbTargetBranch')
        string(defaultValue: '${ghprbPullId}', name: 'ghprbPullId')
        string(defaultValue: '${ghprbActualCommitAuthor}', name: 'ghprbActualCommitAuthor')
        string(defaultValue: '${ghprbActualCommitAuthorEmail}', name: 'ghprbActualCommitAuthorEmail')
        string(defaultValue: '${ghprbTriggerAuthorEmail}', name: 'ghprbTriggerAuthorEmail')
        string(defaultValue: '${GIT_BRANCH}', name: 'GIT_BRANCH')
        string(defaultValue: '${ghprbPullAuthorEmail}', name: 'ghprbPullAuthorEmail')
        string(defaultValue: '${sha1}', name: 'sha1')
        string(defaultValue: '${ghprbSourceBranch}', name: 'ghprbSourceBranch')
    }

    options {
        timeout(time: 300, unit: 'MINUTES')
        timestamps()
        ansiColor('xterm')
    }

    stages {
        stage('Set build name') {
            when {
                not {environment name: 'GIT_BRANCH', value: 'origin/master'}
            }
            steps {
                   script {
                       currentBuild.displayName = env.getProperty('ghprbPullTitle') + '  ' + env.getProperty('ghprbPullLink') + '  ' + currentBuild.displayName
                   }
            }
        }
        stage('Docs') {
            options {
                timeout(time: 20, unit: 'MINUTES')
            }
            steps {
                Status("PENDING", "${env.JOB_NAME}")
                checkout scm
                sh "make -C Documentation html"
            }
        }
    }
    post {
        always {
            cleanWs()
        }
        success {
            Status("SUCCESS", "${env.JOB_NAME}")
        }
        failure {
            Status("FAILURE", "${env.JOB_NAME}")
        }
    }
}

{'repo_name': 'cilium/cilium', 'stars': '5797', 'repo_language': 'Go', 'file_name': 'api_test.go', 'mime_type': 'text/plain', 'hash': -816516629100756605, 'source_dataset': 'data'}


/*==============================================================================

  Program: 3D Slicer

  Copyright (c) Kitware Inc.

  See COPYRIGHT.txt
  or http://www.slicer.org/copyright/copyright.txt for details.

  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.

  This file was originally developed by Jean-Christophe Fillion-Robin, Kitware Inc.
  and was partially funded by NIH grant 3P41RR013218-12S1

==============================================================================*/

#ifndef __qSlicerCorePythonManager_h
#define __qSlicerCorePythonManager_h

// CTK includes
# include <ctkAbstractPythonManager.h>

#include "qSlicerBaseQTCoreExport.h"

class ctkVTKPythonQtWrapperFactory;
class PythonQtObjectPtr;
class vtkObject;

class Q_SLICER_BASE_QTCORE_EXPORT qSlicerCorePythonManager : public ctkAbstractPythonManager
{
  Q_OBJECT

  /// List of directories containing Python modules.
  Q_PROPERTY(QStringList pythonPaths READ pythonPaths)

public:
  typedef ctkAbstractPythonManager Superclass;
  qSlicerCorePythonManager(QObject* parent=nullptr);
  ~qSlicerCorePythonManager() override;

  /// Convenient function allowing to add a VTK object to the interpreter main module
  Q_INVOKABLE void addVTKObjectToPythonMain(const QString& name, vtkObject * object);

  /// Append \a path to \a sys.path
  /// \todo Add these methods to ctkAbstractPythonManager
  /// \sa appendPythonPaths
  Q_INVOKABLE void appendPythonPath(const QString& path);

  /// Append \a paths to \a sys.path
  Q_INVOKABLE void appendPythonPaths(const QStringList& paths);

  /// List of directories containing Python modules.
  QStringList pythonPaths() override;

  /// Convert a string to a safe python string literal.
  /// Backslash, single-quote characters are escaped
  /// and the string is enclosed between single quotes.
  ///
  /// Examples:
  ///   some simple string   => 'some simple string'
  ///   some " string        => 'some " string'
  ///   some other ' string  => 'some other \' string'
  ///   some backslash \ str => 'some backslash \\ str'
  Q_INVOKABLE static QString toPythonStringLiteral(QString path);

protected:

  void preInitialization() override;
  ctkVTKPythonQtWrapperFactory* Factory;

};

#endif

{'repo_name': 'Slicer/SlicerGitSVNArchive', 'stars': '887', 'repo_language': 'C++', 'file_name': 'vtkFSSurfaceReader.h', 'mime_type': 'text/x-c++', 'hash': -6099005913575781145, 'source_dataset': 'data'}


import React, { Component } from 'react';

import styles from './Tooltip.block.css';

interface Props {
  label: string;
  value: string;
  x: number;
  y: number;
}

class Prism extends Component<Props> {

  render() {
    let { label, value, x, y } = this.props;
    return (
      <div
        className={styles}
        tabIndex={0}
        data-label={label}
        data-value={value}
        style={{ top: y+'rem', left: x+'rem' }}></div>
    );
  }

}

export default Prism;

{'repo_name': 'linkedin/css-blocks', 'stars': '6195', 'repo_language': 'TypeScript', 'file_name': 'application.block.css', 'mime_type': 'text/plain', 'hash': -3409267621556882195, 'source_dataset': 'data'}