/* * Copyright 2011 The Netty Project * * The Netty Project licenses this file to you under the Apache License, * version 2.0 (the "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. */ package org.jboss.netty.handler.ssl; import static org.jboss.netty.channel.Channels.*; import java.io.IOException; import java.nio.ByteBuffer; import java.nio.channels.ClosedChannelException; import java.util.LinkedList; import java.util.Queue; import java.util.concurrent.Executor; import java.util.concurrent.atomic.AtomicBoolean; import java.util.regex.Pattern; import javax.net.ssl.SSLEngine; import javax.net.ssl.SSLEngineResult; import javax.net.ssl.SSLEngineResult.HandshakeStatus; import javax.net.ssl.SSLEngineResult.Status; import javax.net.ssl.SSLException; import org.jboss.netty.buffer.ChannelBuffer; import org.jboss.netty.buffer.ChannelBuffers; import org.jboss.netty.channel.Channel; import org.jboss.netty.channel.ChannelDownstreamHandler; import org.jboss.netty.channel.ChannelEvent; import org.jboss.netty.channel.ChannelFuture; import org.jboss.netty.channel.ChannelFutureListener; import org.jboss.netty.channel.ChannelHandlerContext; import org.jboss.netty.channel.ChannelPipeline; import org.jboss.netty.channel.ChannelStateEvent; import org.jboss.netty.channel.Channels; import org.jboss.netty.channel.DownstreamMessageEvent; import org.jboss.netty.channel.ExceptionEvent; import org.jboss.netty.channel.LifeCycleAwareChannelHandler; import org.jboss.netty.channel.MessageEvent; import org.jboss.netty.handler.codec.frame.FrameDecoder; import org.jboss.netty.logging.InternalLogger; import org.jboss.netty.logging.InternalLoggerFactory; import org.jboss.netty.util.internal.NonReentrantLock; import org.jboss.netty.util.internal.QueueFactory; /** * Adds <a href="http://en.wikipedia.org/wiki/Transport_Layer_Security">SSL * · TLS</a> and StartTLS support to a {@link Channel}. Please refer * to the <strong>"SecureChat"</strong> example in the distribution or the web * site for the detailed usage. * * <h3>Beginning the handshake</h3> * <p> * You must make sure not to write a message while the * {@linkplain #handshake() handshake} is in progress unless you are * renegotiating. You will be notified by the {@link ChannelFuture} which is * returned by the {@link #handshake()} method when the handshake * process succeeds or fails. * * <h3>Handshake</h3> * <p> * If {@link #isIssueHandshake()} is {@code false} * (default) you will need to take care of calling {@link #handshake()} by your own. In most situations were {@link SslHandler} is used in 'client mode' * you want to issue a handshake once the connection was established. if {@link #setIssueHandshake(boolean)} is set to <code>true</code> you don't need to * worry about this as the {@link SslHandler} will take care of it. * <p> * * <h3>Renegotiation</h3> * <p> * If {@link #isEnableRenegotiation() enableRenegotiation} is {@code true} * (default) and the initial handshake has been done successfully, you can call * {@link #handshake()} to trigger the renegotiation. * <p> * If {@link #isEnableRenegotiation() enableRenegotiation} is {@code false}, * an attempt to trigger renegotiation will result in the connection closure. * <p> * Please note that TLS renegotiation had a security issue before. If your * runtime environment did not fix it, please make sure to disable TLS * renegotiation by calling {@link #setEnableRenegotiation(boolean)} with * {@code false}. For more information, please refer to the following documents: * <ul> * <li><a href="http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-3555">CVE-2009-3555</a></li> * <li><a href="http://www.ietf.org/rfc/rfc5746.txt">RFC5746</a></li> * <li><a href="http://www.oracle.com/technetwork/java/javase/documentation/tlsreadme2-176330.html">Phased Approach to Fixing the TLS Renegotiation Issue</a></li> * </ul> * * <h3>Closing the session</h3> * <p> * To close the SSL session, the {@link #close()} method should be * called to send the {@code close_notify} message to the remote peer. One * exception is when you close the {@link Channel} - {@link SslHandler} * intercepts the close request and send the {@code close_notify} message * before the channel closure automatically. Once the SSL session is closed, * it is not reusable, and consequently you should create a new * {@link SslHandler} with a new {@link SSLEngine} as explained in the * following section. * * <h3>Restarting the session</h3> * <p> * To restart the SSL session, you must remove the existing closed * {@link SslHandler} from the {@link ChannelPipeline}, insert a new * {@link SslHandler} with a new {@link SSLEngine} into the pipeline, * and start the handshake process as described in the first section. * * <h3>Implementing StartTLS</h3> * <p> * <a href="http://en.wikipedia.org/wiki/STARTTLS">StartTLS</a> is the * communication pattern that secures the wire in the middle of the plaintext * connection. Please note that it is different from SSL · TLS, that * secures the wire from the beginning of the connection. Typically, StartTLS * is composed of three steps: * <ol> * <li>Client sends a StartTLS request to server.</li> * <li>Server sends a StartTLS response to client.</li> * <li>Client begins SSL handshake.</li> * </ol> * If you implement a server, you need to: * <ol> * <li>create a new {@link SslHandler} instance with {@code startTls} flag set * to {@code true},</li> * <li>insert the {@link SslHandler} to the {@link ChannelPipeline}, and</li> * <li>write a StartTLS response.</li> * </ol> * Please note that you must insert {@link SslHandler} <em>before</em> sending * the StartTLS response. Otherwise the client can send begin SSL handshake * before {@link SslHandler} is inserted to the {@link ChannelPipeline}, causing * data corruption. * <p> * The client-side implementation is much simpler. * <ol> * <li>Write a StartTLS request,</li> * <li>wait for the StartTLS response,</li> * <li>create a new {@link SslHandler} instance with {@code startTls} flag set * to {@code false},</li> * <li>insert the {@link SslHandler} to the {@link ChannelPipeline}, and</li> * <li>Initiate SSL handshake by calling {@link SslHandler#handshake()}.</li> * </ol> * * @apiviz.landmark * @apiviz.uses org.jboss.netty.handler.ssl.SslBufferPool */ public class SslHandler extends FrameDecoder implements ChannelDownstreamHandler, LifeCycleAwareChannelHandler { private static final InternalLogger logger = InternalLoggerFactory.getInstance(SslHandler.class); private static final ByteBuffer EMPTY_BUFFER = ByteBuffer.allocate(0); private static final Pattern IGNORABLE_ERROR_MESSAGE = Pattern.compile( "^.*(?:connection.*reset|connection.*closed|broken.*pipe).*$", Pattern.CASE_INSENSITIVE); private static SslBufferPool defaultBufferPool; /** * Returns the default {@link SslBufferPool} used when no pool is * specified in the constructor. */ public static synchronized SslBufferPool getDefaultBufferPool() { if (defaultBufferPool == null) { defaultBufferPool = new SslBufferPool(); } return defaultBufferPool; } private volatile ChannelHandlerContext ctx; private final SSLEngine engine; private final SslBufferPool bufferPool; private final Executor delegatedTaskExecutor; private final boolean startTls; private volatile boolean enableRenegotiation = true; final Object handshakeLock = new Object(); private boolean handshaking; private volatile boolean handshaken; private volatile ChannelFuture handshakeFuture; private final AtomicBoolean sentFirstMessage = new AtomicBoolean(); private final AtomicBoolean sentCloseNotify = new AtomicBoolean(); int ignoreClosedChannelException; final Object ignoreClosedChannelExceptionLock = new Object(); private final Queue<PendingWrite> pendingUnencryptedWrites = new LinkedList<PendingWrite>(); private final Queue<MessageEvent> pendingEncryptedWrites = QueueFactory.createQueue(MessageEvent.class); private final NonReentrantLock pendingEncryptedWritesLock = new NonReentrantLock(); private volatile boolean issueHandshake; private static final ChannelFutureListener HANDSHAKE_LISTENER = new ChannelFutureListener() { public void operationComplete(ChannelFuture future) throws Exception { if (!future.isSuccess()) { Channels.fireExceptionCaught(future.getChannel(), future.getCause()); } } }; /** * Creates a new instance. * * @param engine the {@link SSLEngine} this handler will use */ public SslHandler(SSLEngine engine) { this(engine, getDefaultBufferPool(), ImmediateExecutor.INSTANCE); } /** * Creates a new instance. * * @param engine the {@link SSLEngine} this handler will use * @param bufferPool the {@link SslBufferPool} where this handler will * acquire the buffers required by the {@link SSLEngine} */ public SslHandler(SSLEngine engine, SslBufferPool bufferPool) { this(engine, bufferPool, ImmediateExecutor.INSTANCE); } /** * Creates a new instance. * * @param engine the {@link SSLEngine} this handler will use * @param startTls {@code true} if the first write request shouldn't be * encrypted by the {@link SSLEngine} */ public SslHandler(SSLEngine engine, boolean startTls) { this(engine, getDefaultBufferPool(), startTls); } /** * Creates a new instance. * * @param engine the {@link SSLEngine} this handler will use * @param bufferPool the {@link SslBufferPool} where this handler will * acquire the buffers required by the {@link SSLEngine} * @param startTls {@code true} if the first write request shouldn't be * encrypted by the {@link SSLEngine} */ public SslHandler(SSLEngine engine, SslBufferPool bufferPool, boolean startTls) { this(engine, bufferPool, startTls, ImmediateExecutor.INSTANCE); } /** * Creates a new instance. * * @param engine * the {@link SSLEngine} this handler will use * @param delegatedTaskExecutor * the {@link Executor} which will execute the delegated task * that {@link SSLEngine#getDelegatedTask()} will return */ public SslHandler(SSLEngine engine, Executor delegatedTaskExecutor) { this(engine, getDefaultBufferPool(), delegatedTaskExecutor); } /** * Creates a new instance. * * @param engine * the {@link SSLEngine} this handler will use * @param bufferPool * the {@link SslBufferPool} where this handler will acquire * the buffers required by the {@link SSLEngine} * @param delegatedTaskExecutor * the {@link Executor} which will execute the delegated task * that {@link SSLEngine#getDelegatedTask()} will return */ public SslHandler(SSLEngine engine, SslBufferPool bufferPool, Executor delegatedTaskExecutor) { this(engine, bufferPool, false, delegatedTaskExecutor); } /** * Creates a new instance. * * @param engine * the {@link SSLEngine} this handler will use * @param startTls * {@code true} if the first write request shouldn't be encrypted * by the {@link SSLEngine} * @param delegatedTaskExecutor * the {@link Executor} which will execute the delegated task * that {@link SSLEngine#getDelegatedTask()} will return */ public SslHandler(SSLEngine engine, boolean startTls, Executor delegatedTaskExecutor) { this(engine, getDefaultBufferPool(), startTls, delegatedTaskExecutor); } /** * Creates a new instance. * * @param engine * the {@link SSLEngine} this handler will use * @param bufferPool * the {@link SslBufferPool} where this handler will acquire * the buffers required by the {@link SSLEngine} * @param startTls * {@code true} if the first write request shouldn't be encrypted * by the {@link SSLEngine} * @param delegatedTaskExecutor * the {@link Executor} which will execute the delegated task * that {@link SSLEngine#getDelegatedTask()} will return */ public SslHandler(SSLEngine engine, SslBufferPool bufferPool, boolean startTls, Executor delegatedTaskExecutor) { if (engine == null) { throw new NullPointerException("engine"); } if (bufferPool == null) { throw new NullPointerException("bufferPool"); } if (delegatedTaskExecutor == null) { throw new NullPointerException("delegatedTaskExecutor"); } this.engine = engine; this.bufferPool = bufferPool; this.delegatedTaskExecutor = delegatedTaskExecutor; this.startTls = startTls; } /** * Returns the {@link SSLEngine} which is used by this handler. */ public SSLEngine getEngine() { return engine; } /** * Starts an SSL / TLS handshake for the specified channel. * * @return a {@link ChannelFuture} which is notified when the handshake * succeeds or fails. */ public ChannelFuture handshake() { if (handshaken && !isEnableRenegotiation()) { throw new IllegalStateException("renegotiation disabled"); } ChannelHandlerContext ctx = this.ctx; Channel channel = ctx.getChannel(); ChannelFuture handshakeFuture; Exception exception = null; synchronized (handshakeLock) { if (handshaking) { return this.handshakeFuture; } else { handshaking = true; try { engine.beginHandshake(); runDelegatedTasks(); handshakeFuture = this.handshakeFuture = future(channel); } catch (Exception e) { handshakeFuture = this.handshakeFuture = failedFuture(channel, e); exception = e; } } } if (exception == null) { // Began handshake successfully. try { wrapNonAppData(ctx, channel); } catch (SSLException e) { fireExceptionCaught(ctx, e); handshakeFuture.setFailure(e); } } else { // Failed to initiate handshake. fireExceptionCaught(ctx, exception); } return handshakeFuture; } /** * @deprecated Use {@link #handshake()} instead. */ @Deprecated public ChannelFuture handshake(Channel channel) { return handshake(); } /** * Sends an SSL {@code close_notify} message to the specified channel and * destroys the underlying {@link SSLEngine}. */ public ChannelFuture close() { ChannelHandlerContext ctx = this.ctx; Channel channel = ctx.getChannel(); try { engine.closeOutbound(); return wrapNonAppData(ctx, channel); } catch (SSLException e) { fireExceptionCaught(ctx, e); return failedFuture(channel, e); } } /** * @deprecated Use {@link #close()} instead. */ @Deprecated public ChannelFuture close(Channel channel) { return close(); } /** * Returns {@code true} if and only if TLS renegotiation is enabled. */ public boolean isEnableRenegotiation() { return enableRenegotiation; } /** * Enables or disables TLS renegotiation. */ public void setEnableRenegotiation(boolean enableRenegotiation) { this.enableRenegotiation = enableRenegotiation; } /** * Enables or disables the automatic handshake once the {@link Channel} is * connected. The value will only have affect if its set before the * {@link Channel} is connected. */ public void setIssueHandshake(boolean issueHandshake) { this.issueHandshake = issueHandshake; } /** * Returns <code>true</code> if the automatic handshake is enabled */ public boolean isIssueHandshake() { return issueHandshake; } public void handleDownstream( final ChannelHandlerContext context, final ChannelEvent evt) throws Exception { if (evt instanceof ChannelStateEvent) { ChannelStateEvent e = (ChannelStateEvent) evt; switch (e.getState()) { case OPEN: case CONNECTED: case BOUND: if (Boolean.FALSE.equals(e.getValue()) || e.getValue() == null) { closeOutboundAndChannel(context, e); return; } } } if (!(evt instanceof MessageEvent)) { context.sendDownstream(evt); return; } MessageEvent e = (MessageEvent) evt; if (!(e.getMessage() instanceof ChannelBuffer)) { context.sendDownstream(evt); return; } // Do not encrypt the first write request if this handler is // created with startTLS flag turned on. if (startTls && sentFirstMessage.compareAndSet(false, true)) { context.sendDownstream(evt); return; } // Otherwise, all messages are encrypted. ChannelBuffer msg = (ChannelBuffer) e.getMessage(); PendingWrite pendingWrite; if (msg.readable()) { pendingWrite = new PendingWrite(evt.getFuture(), msg.toByteBuffer(msg.readerIndex(), msg.readableBytes())); } else { pendingWrite = new PendingWrite(evt.getFuture(), null); } synchronized (pendingUnencryptedWrites) { boolean offered = pendingUnencryptedWrites.offer(pendingWrite); assert offered; } wrap(context, evt.getChannel()); } @Override public void channelDisconnected(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception { // Make sure the handshake future is notified when a connection has // been closed during handshake. synchronized (handshakeLock) { if (handshaking) { handshakeFuture.setFailure(new ClosedChannelException()); } } try { super.channelDisconnected(ctx, e); } finally { unwrap(ctx, e.getChannel(), ChannelBuffers.EMPTY_BUFFER, 0, 0); engine.closeOutbound(); if (!sentCloseNotify.get() && handshaken) { try { engine.closeInbound(); } catch (SSLException ex) { if (logger.isDebugEnabled()) { logger.debug("Failed to clean up SSLEngine.", ex); } } } } } @Override public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) throws Exception { Throwable cause = e.getCause(); if (cause instanceof IOException) { if (cause instanceof ClosedChannelException) { synchronized (ignoreClosedChannelExceptionLock) { if (ignoreClosedChannelException > 0) { ignoreClosedChannelException --; if (logger.isDebugEnabled()) { logger.debug( "Swallowing an exception raised while " + "writing non-app data", cause); } return; } } } else if (engine.isOutboundDone()) { String message = String.valueOf(cause.getMessage()).toLowerCase(); if (IGNORABLE_ERROR_MESSAGE.matcher(message).matches()) { // It is safe to ignore the 'connection reset by peer' or // 'broken pipe' error after sending closure_notify. if (logger.isDebugEnabled()) { logger.debug( "Swallowing a 'connection reset by peer / " + "broken pipe' error occurred while writing " + "'closure_notify'", cause); } // Close the connection explicitly just in case the transport // did not close the connection automatically. Channels.close(ctx, succeededFuture(e.getChannel())); return; } } } ctx.sendUpstream(e); } @Override protected Object decode( final ChannelHandlerContext ctx, Channel channel, ChannelBuffer buffer) throws Exception { if (buffer.readableBytes() < 5) { return null; } int packetLength = 0; // SSLv3 or TLS - Check ContentType boolean tls; switch (buffer.getUnsignedByte(buffer.readerIndex())) { case 20: // change_cipher_spec case 21: // alert case 22: // handshake case 23: // application_data tls = true; break; default: // SSLv2 or bad data tls = false; } if (tls) { // SSLv3 or TLS - Check ProtocolVersion int majorVersion = buffer.getUnsignedByte(buffer.readerIndex() + 1); if (majorVersion == 3) { // SSLv3 or TLS packetLength = (getShort(buffer, buffer.readerIndex() + 3) & 0xFFFF) + 5; if (packetLength <= 5) { // Neither SSLv3 or TLSv1 (i.e. SSLv2 or bad data) tls = false; } } else { // Neither SSLv3 or TLSv1 (i.e. SSLv2 or bad data) tls = false; } } if (!tls) { // SSLv2 or bad data - Check the version boolean sslv2 = true; int headerLength = (buffer.getUnsignedByte( buffer.readerIndex()) & 0x80) != 0 ? 2 : 3; int majorVersion = buffer.getUnsignedByte( buffer.readerIndex() + headerLength + 1); if (majorVersion == 2 || majorVersion == 3) { // SSLv2 if (headerLength == 2) { packetLength = (getShort(buffer, buffer.readerIndex()) & 0x7FFF) + 2; } else { packetLength = (getShort(buffer, buffer.readerIndex()) & 0x3FFF) + 3; } if (packetLength <= headerLength) { sslv2 = false; } } else { sslv2 = false; } if (!sslv2) { // Bad data - discard the buffer and raise an exception. SSLException e = new SSLException( "not an SSL/TLS record: " + ChannelBuffers.hexDump(buffer)); buffer.skipBytes(buffer.readableBytes()); throw e; } } assert packetLength > 0; if (buffer.readableBytes() < packetLength) { return null; } // We advance the buffer's readerIndex before calling unwrap() because // unwrap() can trigger FrameDecoder call decode(), this method, recursively. // The recursive call results in decoding the same packet twice if // the readerIndex is advanced *after* decode(). // // Here's an example: // 1) An SSL packet is received from the wire. // 2) SslHandler.decode() deciphers the packet and calls the user code. // 3) The user closes the channel in the same thread. // 4) The same thread triggers a channelDisconnected() event. // 5) FrameDecoder.cleanup() is called, and it calls SslHandler.decode(). // 6) SslHandler.decode() will feed the same packet with what was // deciphered at the step 2 again if the readerIndex was not advanced // before calling the user code. final int packetOffset = buffer.readerIndex(); buffer.skipBytes(packetLength); return unwrap(ctx, channel, buffer, packetOffset, packetLength); } /** * Reads a big-endian short integer from the buffer. Please note that we do not use * {@link ChannelBuffer#getShort(int)} because it might be a little-endian buffer. */ private static short getShort(ChannelBuffer buf, int offset) { return (short) (buf.getByte(offset) << 8 | buf.getByte(offset + 1) & 0xFF); } private ChannelFuture wrap(ChannelHandlerContext context, Channel channel) throws SSLException { ChannelFuture future = null; ChannelBuffer msg; ByteBuffer outNetBuf = bufferPool.acquire(); boolean success = true; boolean offered = false; boolean needsUnwrap = false; try { loop: for (;;) { // Acquire a lock to make sure unencrypted data is polled // in order and their encrypted counterpart is offered in // order. synchronized (pendingUnencryptedWrites) { PendingWrite pendingWrite = pendingUnencryptedWrites.peek(); if (pendingWrite == null) { break; } ByteBuffer outAppBuf = pendingWrite.outAppBuf; if (outAppBuf == null) { // A write request with an empty buffer pendingUnencryptedWrites.remove(); offerEncryptedWriteRequest( new DownstreamMessageEvent( channel, pendingWrite.future, ChannelBuffers.EMPTY_BUFFER, channel.getRemoteAddress())); offered = true; } else { SSLEngineResult result = null; try { synchronized (handshakeLock) { result = engine.wrap(outAppBuf, outNetBuf); } } finally { if (!outAppBuf.hasRemaining()) { pendingUnencryptedWrites.remove(); } } if (result.bytesProduced() > 0) { outNetBuf.flip(); msg = ChannelBuffers.buffer(outNetBuf.remaining()); msg.writeBytes(outNetBuf.array(), 0, msg.capacity()); outNetBuf.clear(); if (pendingWrite.outAppBuf.hasRemaining()) { // pendingWrite's future shouldn't be notified if // only partial data is written. future = succeededFuture(channel); } else { future = pendingWrite.future; } MessageEvent encryptedWrite = new DownstreamMessageEvent( channel, future, msg, channel.getRemoteAddress()); offerEncryptedWriteRequest(encryptedWrite); offered = true; } else if (result.getStatus() == Status.CLOSED) { // SSLEngine has been closed already. // Any further write attempts should be denied. success = false; break; } else { final HandshakeStatus handshakeStatus = result.getHandshakeStatus(); handleRenegotiation(handshakeStatus); switch (handshakeStatus) { case NEED_WRAP: if (outAppBuf.hasRemaining()) { break; } else { break loop; } case NEED_UNWRAP: needsUnwrap = true; break loop; case NEED_TASK: runDelegatedTasks(); break; case FINISHED: case NOT_HANDSHAKING: if (handshakeStatus == HandshakeStatus.FINISHED) { setHandshakeSuccess(channel); } if (result.getStatus() == Status.CLOSED) { success = false; } break loop; default: throw new IllegalStateException( "Unknown handshake status: " + handshakeStatus); } } } } } } catch (SSLException e) { success = false; setHandshakeFailure(channel, e); throw e; } finally { bufferPool.release(outNetBuf); if (offered) { flushPendingEncryptedWrites(context); } if (!success) { IllegalStateException cause = new IllegalStateException("SSLEngine already closed"); // Mark all remaining pending writes as failure if anything // wrong happened before the write requests are wrapped. // Please note that we do not call setFailure while a lock is // acquired, to avoid a potential dead lock. for (;;) { PendingWrite pendingWrite; synchronized (pendingUnencryptedWrites) { pendingWrite = pendingUnencryptedWrites.poll(); if (pendingWrite == null) { break; } } pendingWrite.future.setFailure(cause); } } } if (needsUnwrap) { unwrap(context, channel, ChannelBuffers.EMPTY_BUFFER, 0, 0); } if (future == null) { future = succeededFuture(channel); } return future; } private void offerEncryptedWriteRequest(MessageEvent encryptedWrite) { final boolean locked = pendingEncryptedWritesLock.tryLock(); try { pendingEncryptedWrites.offer(encryptedWrite); } finally { if (locked) { pendingEncryptedWritesLock.unlock(); } } } private void flushPendingEncryptedWrites(ChannelHandlerContext ctx) { // Avoid possible dead lock and data integrity issue // which is caused by cross communication between more than one channel // in the same VM. if (!pendingEncryptedWritesLock.tryLock()) { return; } try { MessageEvent e; while ((e = pendingEncryptedWrites.poll()) != null) { ctx.sendDownstream(e); } } finally { pendingEncryptedWritesLock.unlock(); } } private ChannelFuture wrapNonAppData(ChannelHandlerContext ctx, Channel channel) throws SSLException { ChannelFuture future = null; ByteBuffer outNetBuf = bufferPool.acquire(); SSLEngineResult result; try { for (;;) { synchronized (handshakeLock) { result = engine.wrap(EMPTY_BUFFER, outNetBuf); } if (result.bytesProduced() > 0) { outNetBuf.flip(); ChannelBuffer msg = ChannelBuffers.buffer(outNetBuf.remaining()); msg.writeBytes(outNetBuf.array(), 0, msg.capacity()); outNetBuf.clear(); future = future(channel); future.addListener(new ChannelFutureListener() { public void operationComplete(ChannelFuture future) throws Exception { if (future.getCause() instanceof ClosedChannelException) { synchronized (ignoreClosedChannelExceptionLock) { ignoreClosedChannelException ++; } } } }); write(ctx, future, msg); } final HandshakeStatus handshakeStatus = result.getHandshakeStatus(); handleRenegotiation(handshakeStatus); switch (handshakeStatus) { case FINISHED: setHandshakeSuccess(channel); runDelegatedTasks(); break; case NEED_TASK: runDelegatedTasks(); break; case NEED_UNWRAP: if (!Thread.holdsLock(handshakeLock)) { // unwrap shouldn't be called when this method was // called by unwrap - unwrap will keep running after // this method returns. unwrap(ctx, channel, ChannelBuffers.EMPTY_BUFFER, 0, 0); } break; case NOT_HANDSHAKING: case NEED_WRAP: break; default: throw new IllegalStateException( "Unexpected handshake status: " + handshakeStatus); } if (result.bytesProduced() == 0) { break; } } } catch (SSLException e) { setHandshakeFailure(channel, e); throw e; } finally { bufferPool.release(outNetBuf); } if (future == null) { future = succeededFuture(channel); } return future; } private ChannelBuffer unwrap( ChannelHandlerContext ctx, Channel channel, ChannelBuffer buffer, int offset, int length) throws SSLException { ByteBuffer inNetBuf = buffer.toByteBuffer(offset, length); ByteBuffer outAppBuf = bufferPool.acquire(); try { boolean needsWrap = false; loop: for (;;) { SSLEngineResult result; boolean needsHandshake = false; synchronized (handshakeLock) { if (!handshaken && !handshaking && !engine.getUseClientMode() && !engine.isInboundDone() && !engine.isOutboundDone()) { needsHandshake = true; } } if (needsHandshake) { handshake(); } synchronized (handshakeLock) { result = engine.unwrap(inNetBuf, outAppBuf); } final HandshakeStatus handshakeStatus = result.getHandshakeStatus(); handleRenegotiation(handshakeStatus); switch (handshakeStatus) { case NEED_UNWRAP: if (inNetBuf.hasRemaining() && !engine.isInboundDone()) { break; } else { break loop; } case NEED_WRAP: wrapNonAppData(ctx, channel); break; case NEED_TASK: runDelegatedTasks(); break; case FINISHED: setHandshakeSuccess(channel); needsWrap = true; break loop; case NOT_HANDSHAKING: needsWrap = true; break loop; default: throw new IllegalStateException( "Unknown handshake status: " + handshakeStatus); } } if (needsWrap) { // wrap() acquires pendingUnencryptedWrites first and then // handshakeLock. If handshakeLock is already hold by the // current thread, calling wrap() will lead to a dead lock // i.e. pendingUnencryptedWrites -> handshakeLock vs. // handshakeLock -> pendingUnencryptedLock -> handshakeLock // // There is also a same issue between pendingEncryptedWrites // and pendingUnencryptedWrites. if (!Thread.holdsLock(handshakeLock) && !pendingEncryptedWritesLock.isHeldByCurrentThread()) { wrap(ctx, channel); } } outAppBuf.flip(); if (outAppBuf.hasRemaining()) { ChannelBuffer frame = ctx.getChannel().getConfig().getBufferFactory().getBuffer(outAppBuf.remaining()); frame.writeBytes(outAppBuf.array(), 0, frame.capacity()); return frame; } else { return null; } } catch (SSLException e) { setHandshakeFailure(channel, e); throw e; } finally { bufferPool.release(outAppBuf); } } private void handleRenegotiation(HandshakeStatus handshakeStatus) { if (handshakeStatus == HandshakeStatus.NOT_HANDSHAKING || handshakeStatus == HandshakeStatus.FINISHED) { // Not handshaking return; } if (!handshaken) { // Not renegotiation return; } final boolean renegotiate; synchronized (handshakeLock) { if (handshaking) { // Renegotiation in progress or failed already. // i.e. Renegotiation check has been done already below. return; } if (engine.isInboundDone() || engine.isOutboundDone()) { // Not handshaking but closing. return; } if (isEnableRenegotiation()) { // Continue renegotiation. renegotiate = true; } else { // Do not renegotiate. renegotiate = false; // Prevent reentrance of this method. handshaking = true; } } if (renegotiate) { // Renegotiate. handshake(); } else { // Raise an exception. fireExceptionCaught( ctx, new SSLException( "renegotiation attempted by peer; " + "closing the connection")); // Close the connection to stop renegotiation. Channels.close(ctx, succeededFuture(ctx.getChannel())); } } private void runDelegatedTasks() { for (;;) { final Runnable task; synchronized (handshakeLock) { task = engine.getDelegatedTask(); } if (task == null) { break; } delegatedTaskExecutor.execute(new Runnable() { public void run() { synchronized (handshakeLock) { task.run(); } } }); } } private void setHandshakeSuccess(Channel channel) { synchronized (handshakeLock) { handshaking = false; handshaken = true; if (handshakeFuture == null) { handshakeFuture = future(channel); } } handshakeFuture.setSuccess(); } private void setHandshakeFailure(Channel channel, SSLException cause) { synchronized (handshakeLock) { if (!handshaking) { return; } handshaking = false; handshaken = false; if (handshakeFuture == null) { handshakeFuture = future(channel); } // Release all resources such as internal buffers that SSLEngine // is managing. engine.closeOutbound(); try { engine.closeInbound(); } catch (SSLException e) { if (logger.isDebugEnabled()) { logger.debug( "SSLEngine.closeInbound() raised an exception after " + "a handshake failure.", e); } } } handshakeFuture.setFailure(cause); } private void closeOutboundAndChannel( final ChannelHandlerContext context, final ChannelStateEvent e) { if (!e.getChannel().isConnected()) { context.sendDownstream(e); return; } boolean success = false; try { try { unwrap(context, e.getChannel(), ChannelBuffers.EMPTY_BUFFER, 0, 0); } catch (SSLException ex) { if (logger.isDebugEnabled()) { logger.debug("Failed to unwrap before sending a close_notify message", ex); } } if (!engine.isInboundDone()) { if (sentCloseNotify.compareAndSet(false, true)) { engine.closeOutbound(); try { ChannelFuture closeNotifyFuture = wrapNonAppData(context, e.getChannel()); closeNotifyFuture.addListener( new ClosingChannelFutureListener(context, e)); success = true; } catch (SSLException ex) { if (logger.isDebugEnabled()) { logger.debug("Failed to encode a close_notify message", ex); } } } } else { success = true; } } finally { if (!success) { context.sendDownstream(e); } } } private static final class PendingWrite { final ChannelFuture future; final ByteBuffer outAppBuf; PendingWrite(ChannelFuture future, ByteBuffer outAppBuf) { this.future = future; this.outAppBuf = outAppBuf; } } private static final class ClosingChannelFutureListener implements ChannelFutureListener { private final ChannelHandlerContext context; private final ChannelStateEvent e; ClosingChannelFutureListener( ChannelHandlerContext context, ChannelStateEvent e) { this.context = context; this.e = e; } public void operationComplete(ChannelFuture closeNotifyFuture) throws Exception { if (!(closeNotifyFuture.getCause() instanceof ClosedChannelException)) { Channels.close(context, e.getFuture()); } else { e.getFuture().setSuccess(); } } } public void beforeAdd(ChannelHandlerContext ctx) throws Exception { this.ctx = ctx; } public void afterAdd(ChannelHandlerContext ctx) throws Exception { // Unused } public void beforeRemove(ChannelHandlerContext ctx) throws Exception { // Unused } public void afterRemove(ChannelHandlerContext ctx) throws Exception { // Unused } /** * Calls {@link #handshake()} once the {@link Channel} is connected */ @Override public void channelConnected(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception { if (issueHandshake) { // issue and handshake and add a listener to it which will fire an exception event if an exception was thrown while doing the handshake handshake().addListener(HANDSHAKE_LISTENER); } super.channelConnected(ctx, e); } }