java SSLEngine说NEED_WRAP，调用.wrap（）仍然是NEED_WRAP

Question

我看到SSLEngine有一个奇怪的问题，想知道我的代码或SSLEngine是否有问题。这是我看到事物的顺序

1. 握手状态为NEED_WRAP
2. 我们称SSLEngine.WRAP
3. 之后，将零数据写入缓冲区，并且SSLEngineResult.result = OK（既不溢出也不下溢:(），HandshakeStatus为STILL NEED_WRAP

最重要的问题：如何彻底调试？如何以某种方式“看到”每条消息？我可以很容易地捕获字节流，但是是否有一些库可以将其解析为SSL握手对象？

第298行（记录先前的握手状态）到第328行（在此将异常与信息一起抛出）是此处的相关代码

https://github.com/deanhiller/webpieces/blob/sslEngineFartingExample/core/core-ssl/src/main/java/org/webpieces/ssl/impl/AsyncSSLEngine3Impl.java

堆栈跟踪为

2019-06-21 08:58:24,562 [-] [webpiecesThreadPool6] Caller+1  at org.webpieces.util.threading.SessionExecutorImpl$RunnableWithKey.run(SessionExecutorImpl.java:123)
  ERROR: Uncaught Exception
java.lang.IllegalStateException: Engine issue.  hsStatus=NEED_WRAP status=OK previous hsStatus=NEED_WRAP
    at org.webpieces.ssl.impl.AsyncSSLEngine3Impl.sendHandshakeMessageImpl(AsyncSSLEngine3Impl.java:328)
    at org.webpieces.ssl.impl.AsyncSSLEngine3Impl.sendHandshakeMessage(AsyncSSLEngine3Impl.java:286)
    at org.webpieces.ssl.impl.AsyncSSLEngine3Impl.doHandshakeWork(AsyncSSLEngine3Impl.java:133)
    at org.webpieces.ssl.impl.AsyncSSLEngine3Impl.doHandshakeLoop(AsyncSSLEngine3Impl.java:246)
    at org.webpieces.ssl.impl.AsyncSSLEngine3Impl.unwrapPacket(AsyncSSLEngine3Impl.java:210)
    at org.webpieces.ssl.impl.AsyncSSLEngine3Impl.doWork(AsyncSSLEngine3Impl.java:109)
    at org.webpieces.ssl.impl.AsyncSSLEngine3Impl.feedEncryptedPacket(AsyncSSLEngine3Impl.java:82)
    at org.webpieces.nio.impl.ssl.SslTCPChannel$SocketDataListener.incomingData(SslTCPChannel.java:175)
    at org.webpieces.nio.impl.threading.ThreadDataListener$1.run(ThreadDataListener.java:26)
    at org.webpieces.util.threading.SessionExecutorImpl$RunnableWithKey.run(SessionExecutorImpl.java:121)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
    at java.base/java.lang.Thread.run(Thread.java:834)

有任何想法吗？我该如何真正深入研究呢？我的喜好是一个库，它使用字节并吐出代表每个握手消息或解密数据包的ssl对象（带有原始加密内容附带的任何标头信息）。

具体来说，这是上面提到的代码

        HandshakeStatus previousStatus = sslEngine.getHandshakeStatus();
    //CLOSE and all the threads that call feedPlainPacket can have contention on wrapping to encrypt and
    //must synchronize on sslEngine.wrap
    Status lastStatus;
    HandshakeStatus hsStatus;
    synchronized (wrapLock ) {

        HandshakeStatus beforeWrapHandshakeStatus = sslEngine.getHandshakeStatus();
        if (beforeWrapHandshakeStatus != HandshakeStatus.NEED_WRAP)
            throw new IllegalStateException("we should only be calling this method when hsStatus=NEED_WRAP.  hsStatus=" + beforeWrapHandshakeStatus);

        //KEEEEEP This very small.  wrap and then listener.packetEncrypted
        SSLEngineResult result = sslEngine.wrap(SslMementoImpl.EMPTY, engineToSocketData);
        lastStatus = result.getStatus();
        hsStatus = result.getHandshakeStatus();
    }

    log.trace(()->mem+"write packet pos="+engineToSocketData.position()+" lim="+
                    engineToSocketData.limit()+" status="+lastStatus+" hs="+hsStatus);

    if(lastStatus == Status.BUFFER_OVERFLOW || lastStatus == Status.BUFFER_UNDERFLOW)
        throw new RuntimeException("status not right, status="+lastStatus+" even though we sized the buffer to consume all?");

    boolean readNoData = engineToSocketData.position() == 0;
    engineToSocketData.flip();
    try {
        CompletableFuture<Void> sentMsgFuture;
        if(readNoData) {
            log.trace(() -> "ssl engine is farting. READ 0 data.  hsStatus="+hsStatus+" status="+lastStatus);

            throw new IllegalStateException("Engine issue.  hsStatus="+hsStatus+" status="+lastStatus+" previous hsStatus="+previousStatus);
            //A big hack since the Engine was not working in live testing with FireFox and it would tell us to wrap
            //and NOT output any data AND not BufferOverflow.....you have to do 1 or the other, right!
            //instead cut out of looping since there seems to be no data
            //sslEngineIsFarting = true;
            //sentMsgFuture = CompletableFuture.completedFuture(null);

谢谢，院长

Answer 1

System.setProperty("jdk.tls.server.protocols", "TLSv1.2");

System.setProperty("jdk.tls.client.protocols", "TLSv1.2");

应在加载 JSSE 之前设置系统属性。例如，在命令行中设置属性。是系统属性不适合你的原因吗？

...SSLEngine 告诉我们需要 WRAP，这是正确的，因为我们还需要用 close_notify 进行回复以防止截断攻击，但引擎返回 0 字节并告诉我们引擎的状态仍然是 NEED_WRAP。

TLS 1.3 使用半关闭策略（请参阅 RFC 8446）。当收到close_notify时，入站侧将关闭，出站侧保持打开状态。本端不能接收任何数据，但可以发送更多的应用数据。

半关闭策略会对兼容性产生一些影响（请参阅 JDK 11 发行说明，https://www.oracle.com/technetwork/java/javase/11-relnote-issues-5012449.html）。系统属性“jdk.tls.acknowledgeCloseNotify”可用作解决方法。有关更多详细信息，请参阅 JDK 11 发行说明。