/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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.apache.tomcat.websocket;
import java.io.EOFException;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.AsynchronousSocketChannel;
import java.nio.channels.CompletionHandler;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.atomic.AtomicBoolean;
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.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.apache.tomcat.util.res.StringManager;
/**
* Wraps the {@link AsynchronousSocketChannel} with SSL/TLS. This needs a lot
* more testing before it can be considered robust.
*/
public class AsyncChannelWrapperSecure implements AsyncChannelWrapper {
private static final Log log =
LogFactory.getLog(AsyncChannelWrapperSecure.class);
private static final StringManager sm =
StringManager.getManager(Constants.PACKAGE_NAME);
private static final ByteBuffer DUMMY = ByteBuffer.allocate(8192);
private final AsynchronousSocketChannel socketChannel;
private final SSLEngine sslEngine;
private final ByteBuffer socketReadBuffer;
private final ByteBuffer socketWriteBuffer;
// One thread for read, one for write
private final ExecutorService executor = Executors.newFixedThreadPool(2);
private AtomicBoolean writing = new AtomicBoolean(false);
private AtomicBoolean reading = new AtomicBoolean(false);
public AsyncChannelWrapperSecure(AsynchronousSocketChannel socketChannel,
SSLEngine sslEngine) {
this.socketChannel = socketChannel;
this.sslEngine = sslEngine;
int socketBufferSize = sslEngine.getSession().getPacketBufferSize();
socketReadBuffer = ByteBuffer.allocateDirect(socketBufferSize);
socketWriteBuffer = ByteBuffer.allocateDirect(socketBufferSize);
}
@Override
public Future<Integer> read(ByteBuffer dst) {
WrapperFuture<Integer,Void> future = new WrapperFuture<>();
if (!reading.compareAndSet(false, true)) {
throw new IllegalStateException(sm.getString(
"asyncChannelWrapperSecure.concurrentRead"));
}
ReadTask readTask = new ReadTask(dst, future);
executor.execute(readTask);
return future;
}
@Override
public <B,A extends B> void read(ByteBuffer dst, A attachment,
CompletionHandler<Integer,B> handler) {
WrapperFuture<Integer,B> future =
new WrapperFuture<>(handler, attachment);
if (!reading.compareAndSet(false, true)) {
throw new IllegalStateException(sm.getString(
"asyncChannelWrapperSecure.concurrentRead"));
}
ReadTask readTask = new ReadTask(dst, future);
executor.execute(readTask);
}
@Override
public Future<Integer> write(ByteBuffer src) {
WrapperFuture<Long,Void> inner = new WrapperFuture<>();
if (!writing.compareAndSet(false, true)) {
throw new IllegalStateException(sm.getString(
"asyncChannelWrapperSecure.concurrentWrite"));
}
WriteTask writeTask =
new WriteTask(new ByteBuffer[] {src}, 0, 1, inner);
executor.execute(writeTask);
Future<Integer> future = new LongToIntegerFuture(inner);
return future;
}
@Override
public <B,A extends B> void write(ByteBuffer[] srcs, int offset, int length,
long timeout, TimeUnit unit, A attachment,
CompletionHandler<Long,B> handler) {
WrapperFuture<Long,B> future =
new WrapperFuture<>(handler, attachment);
if (!writing.compareAndSet(false, true)) {
throw new IllegalStateException(sm.getString(
"asyncChannelWrapperSecure.concurrentWrite"));
}
WriteTask writeTask = new WriteTask(srcs, offset, length, future);
executor.execute(writeTask);
}
@Override
public void close() {
try {
socketChannel.close();
} catch (IOException e) {
log.info(sm.getString("asyncChannelWrapperSecure.closeFail"));
}
}
@Override
public Future<Void> handshake() throws SSLException {
WrapperFuture<Void,Void> wFuture = new WrapperFuture<>();
Thread t = new WebSocketSslHandshakeThread(wFuture);
t.start();
return wFuture;
}
private class WriteTask implements Runnable {
private final ByteBuffer[] srcs;
private final int offset;
private final int length;
private final WrapperFuture<Long,?> future;
public WriteTask(ByteBuffer[] srcs, int offset, int length,
WrapperFuture<Long,?> future) {
this.srcs = srcs;
this.future = future;
this.offset = offset;
this.length = length;
}
@Override
public void run() {
long written = 0;
try {
for (int i = offset; i < offset + length; i++) {
ByteBuffer src = srcs[i];
while (src.hasRemaining()) {
socketWriteBuffer.clear();
// Encrypt the data
SSLEngineResult r = sslEngine.wrap(src, socketWriteBuffer);
written += r.bytesConsumed();
Status s = r.getStatus();
if (s == Status.OK || s == Status.BUFFER_OVERFLOW) {
// Need to write out the bytes and may need to read from
// the source again to empty it
} else {
// Status.BUFFER_UNDERFLOW - only happens on unwrap
// Status.CLOSED - unexpected
throw new IllegalStateException(sm.getString(
"asyncChannelWrapperSecure.statusWrap"));
}
// Check for tasks
if (r.getHandshakeStatus() == HandshakeStatus.NEED_TASK) {
Runnable runnable = sslEngine.getDelegatedTask();
while (runnable != null) {
runnable.run();
runnable = sslEngine.getDelegatedTask();
}
}
socketWriteBuffer.flip();
// Do the write
int toWrite = r.bytesProduced();
while (toWrite > 0) {
Future<Integer> f =
socketChannel.write(socketWriteBuffer);
Integer socketWrite = f.get();
toWrite -= socketWrite.intValue();
}
}
}
if (writing.compareAndSet(true, false)) {
future.complete(Long.valueOf(written));
} else {
future.fail(new IllegalStateException(sm.getString(
"asyncChannelWrapperSecure.wrongStateWrite")));
}
} catch (Exception e) {
future.fail(e);
}
}
}
private class ReadTask implements Runnable {
private final ByteBuffer dest;
private final WrapperFuture<Integer,?> future;
public ReadTask(ByteBuffer dest, WrapperFuture<Integer,?> future) {
this.dest = dest;
this.future = future;
}
@Override
public void run() {
int read = 0;
boolean forceRead = false;
try {
while (read == 0) {
socketReadBuffer.compact();
if (forceRead) {
Future<Integer> f =
socketChannel.read(socketReadBuffer);
Integer socketRead = f.get();
if (socketRead.intValue() == -1) {
throw new EOFException(sm.getString(
"asyncChannelWrapperSecure.eof"));
}
}
socketReadBuffer.flip();
if (socketReadBuffer.hasRemaining()) {
// Decrypt the data in the buffer
SSLEngineResult r =
sslEngine.unwrap(socketReadBuffer, dest);
read += r.bytesProduced();
Status s = r.getStatus();
if (s == Status.OK) {
// Bytes available for reading and there may be
// sufficient data in the socketReadBuffer to
// support further reads without reading from the
// socket
} else if (s == Status.BUFFER_UNDERFLOW) {
// There is partial data in the socketReadBuffer
if (read == 0) {
// Need more data before the partial data can be
// processed and some output generated
forceRead = true;
}
// else return the data we have and deal with the
// partial data on the next read
} else if (s == Status.BUFFER_OVERFLOW) {
// Not enough space in the destination buffer to
// store all of the data. We could use a bytes read
// value of -bufferSizeRequired to signal the new
// buffer size required but an explicit exception is
// clearer.
if (reading.compareAndSet(true, false)) {
throw new ReadBufferOverflowException(sslEngine.
getSession().getApplicationBufferSize());
} else {
future.fail(new IllegalStateException(sm.getString(
"asyncChannelWrapperSecure.wrongStateRead")));
}
} else {
// Status.CLOSED - unexpected
throw new IllegalStateException(sm.getString(
"asyncChannelWrapperSecure.statusUnwrap"));
}
// Check for tasks
if (r.getHandshakeStatus() == HandshakeStatus.NEED_TASK) {
Runnable runnable = sslEngine.getDelegatedTask();
while (runnable != null) {
runnable.run();
runnable = sslEngine.getDelegatedTask();
}
}
} else {
forceRead = true;
}
}
if (reading.compareAndSet(true, false)) {
future.complete(Integer.valueOf(read));
} else {
future.fail(new IllegalStateException(sm.getString(
"asyncChannelWrapperSecure.wrongStateRead")));
}
} catch (Exception e) {
future.fail(e);
}
}
}
private class WebSocketSslHandshakeThread extends Thread {
private final WrapperFuture<Void,Void> hFuture;
private HandshakeStatus handshakeStatus;
private Status resultStatus;
public WebSocketSslHandshakeThread(WrapperFuture<Void,Void> hFuture) {
this.hFuture = hFuture;
}
@Override
public void run() {
try {
sslEngine.beginHandshake();
// So the first compact does the right thing
socketReadBuffer.position(socketReadBuffer.limit());
handshakeStatus = sslEngine.getHandshakeStatus();
resultStatus = Status.OK;
boolean handshaking = true;
while(handshaking) {
switch (handshakeStatus) {
case NEED_WRAP: {
socketWriteBuffer.clear();
SSLEngineResult r =
sslEngine.wrap(DUMMY, socketWriteBuffer);
checkResult(r, true);
socketWriteBuffer.flip();
Future<Integer> fWrite =
socketChannel.write(socketWriteBuffer);
fWrite.get();
break;
}
case NEED_UNWRAP: {
socketReadBuffer.compact();
if (socketReadBuffer.position() == 0 ||
resultStatus == Status.BUFFER_UNDERFLOW) {
Future<Integer> fRead =
socketChannel.read(socketReadBuffer);
fRead.get();
}
socketReadBuffer.flip();
SSLEngineResult r =
sslEngine.unwrap(socketReadBuffer, DUMMY);
checkResult(r, false);
break;
}
case NEED_TASK: {
Runnable r = null;
while ((r = sslEngine.getDelegatedTask()) != null) {
r.run();
}
handshakeStatus = sslEngine.getHandshakeStatus();
break;
}
case FINISHED: {
handshaking = false;
break;
}
default: {
throw new SSLException("TODO");
}
}
}
} catch (SSLException | InterruptedException |
ExecutionException e) {
hFuture.fail(e);
}
hFuture.complete(null);
}
private void checkResult(SSLEngineResult result, boolean wrap)
throws SSLException {
handshakeStatus = result.getHandshakeStatus();
resultStatus = result.getStatus();
if (resultStatus != Status.OK &&
(wrap || resultStatus != Status.BUFFER_UNDERFLOW)) {
throw new SSLException("TODO");
}
if (wrap && result.bytesConsumed() != 0) {
throw new SSLException("TODO");
}
if (!wrap && result.bytesProduced() != 0) {
throw new SSLException("TODO");
}
}
}
private static class WrapperFuture<T,A> implements Future<T> {
private final CompletionHandler<T,A> handler;
private final A attachment;
private volatile T result = null;
private volatile Throwable throwable = null;
private CountDownLatch completionLatch = new CountDownLatch(1);
public WrapperFuture() {
this(null, null);
}
public WrapperFuture(CompletionHandler<T,A> handler, A attachment) {
this.handler = handler;
this.attachment = attachment;
}
public void complete(T result) {
this.result = result;
completionLatch.countDown();
if (handler != null) {
handler.completed(result, attachment);
}
}
public void fail(Throwable t) {
throwable = t;
completionLatch.countDown();
if (handler != null) {
handler.failed(throwable, attachment);
}
}
@Override
public final boolean cancel(boolean mayInterruptIfRunning) {
// Could support cancellation by closing the connection
return false;
}
@Override
public final boolean isCancelled() {
// Could support cancellation by closing the connection
return false;
}
@Override
public final boolean isDone() {
return completionLatch.getCount() > 0;
}
@Override
public T get() throws InterruptedException, ExecutionException {
completionLatch.await();
if (throwable != null) {
throw new ExecutionException(throwable);
}
return result;
}
@Override
public T get(long timeout, TimeUnit unit)
throws InterruptedException, ExecutionException,
TimeoutException {
boolean latchResult = completionLatch.await(timeout, unit);
if (latchResult == false) {
throw new TimeoutException();
}
if (throwable != null) {
throw new ExecutionException(throwable);
}
return result;
}
}
private static final class LongToIntegerFuture implements Future<Integer> {
private final Future<Long> wrapped;
public LongToIntegerFuture(Future<Long> wrapped) {
this.wrapped = wrapped;
}
@Override
public boolean cancel(boolean mayInterruptIfRunning) {
return wrapped.cancel(mayInterruptIfRunning);
}
@Override
public boolean isCancelled() {
return wrapped.isCancelled();
}
@Override
public boolean isDone() {
return wrapped.isDone();
}
@Override
public Integer get() throws InterruptedException, ExecutionException {
Long result = wrapped.get();
if (result.longValue() > Integer.MAX_VALUE) {
throw new ExecutionException(sm.getString(
"asyncChannelWrapperSecure.tooBig", result), null);
}
return new Integer(result.intValue());
}
@Override
public Integer get(long timeout, TimeUnit unit)
throws InterruptedException, ExecutionException,
TimeoutException {
Long result = wrapped.get(timeout, unit);
if (result.longValue() > Integer.MAX_VALUE) {
throw new ExecutionException(sm.getString(
"asyncChannelWrapperSecure.tooBig", result), null);
}
return new Integer(result.intValue());
}
}
}