Fixes #7935 - Review HTTP/2 error handling

Now returning error handling code as a Runnable.

Signed-off-by: Simone Bordet <simone.bordet@gmail.com>

jetty-http2/http2-server/src/main/java/org/eclipse/jetty/http2/server/HttpChannelOverHTTP2.java

@@ -158,13 +158,11 @@ public Runnable onRequest(HeadersFrame frame)
         {
             if (LOG.isDebugEnabled())
                 LOG.debug("onRequest", x);
-            onBadMessage(x);
-            return null;
+            return () -> onBadMessage(x);
         }
         catch (Throwable x)
         {
-            onBadMessage(new BadMessageException(HttpStatus.INTERNAL_SERVER_ERROR_500, null, x));
-            return null;
+            return () -> onBadMessage(new BadMessageException(HttpStatus.INTERNAL_SERVER_ERROR_500, null, x));
         }
     }
 
@@ -190,13 +188,11 @@ public Runnable onPushRequest(MetaData.Request request)
         }
         catch (BadMessageException x)
         {
-            onBadMessage(x);
-            return null;
+            return () -> onBadMessage(x);
         }
         catch (Throwable x)
         {
-            onBadMessage(new BadMessageException(HttpStatus.INTERNAL_SERVER_ERROR_500, null, x));
-            return null;
+            return () -> onBadMessage(new BadMessageException(HttpStatus.INTERNAL_SERVER_ERROR_500, null, x));
         }
     }
 

jetty-http2/http2-server/src/test/java/org/eclipse/jetty/http2/server/BadURITest.java

@@ -0,0 +1,153 @@
+//
+// ========================================================================
+// Copyright (c) 1995-2022 Mort Bay Consulting Pty Ltd and others.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
+// which is available at https://www.apache.org/licenses/LICENSE-2.0.
+//
+// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
+// ========================================================================
+//
+
+package org.eclipse.jetty.http2.server;
+
+import java.io.OutputStream;
+import java.net.Socket;
+import java.nio.ByteBuffer;
+import java.util.HashMap;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.eclipse.jetty.http.HostPortHttpField;
+import org.eclipse.jetty.http.HttpFields;
+import org.eclipse.jetty.http.HttpMethod;
+import org.eclipse.jetty.http.HttpScheme;
+import org.eclipse.jetty.http.HttpVersion;
+import org.eclipse.jetty.http.MetaData;
+import org.eclipse.jetty.http2.frames.HeadersFrame;
+import org.eclipse.jetty.http2.frames.PrefaceFrame;
+import org.eclipse.jetty.http2.frames.SettingsFrame;
+import org.eclipse.jetty.http2.generator.Generator;
+import org.eclipse.jetty.io.ByteBufferPool;
+import org.eclipse.jetty.server.Handler;
+import org.eclipse.jetty.server.HttpConfiguration;
+import org.eclipse.jetty.server.Request;
+import org.eclipse.jetty.server.Server;
+import org.eclipse.jetty.server.ServerConnector;
+import org.eclipse.jetty.server.handler.AbstractHandler;
+import org.eclipse.jetty.server.handler.ErrorHandler;
+import org.eclipse.jetty.util.BufferUtil;
+import org.eclipse.jetty.util.component.LifeCycle;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class BadURITest
+{
+    private Server server;
+    private ServerConnector connector;
+
+    protected void startServer(Handler handler) throws Exception
+    {
+        server = new Server();
+        connector = new ServerConnector(server, 1, 1, new HTTP2CServerConnectionFactory(new HttpConfiguration()));
+        server.addConnector(connector);
+        server.setHandler(handler);
+        server.start();
+    }
+
+    @AfterEach
+    public void dispose()
+    {
+        LifeCycle.stop(server);
+    }
+
+    @Test
+    public void testBadURI() throws Exception
+    {
+        CountDownLatch handlerLatch = new CountDownLatch(1);
+        startServer(new AbstractHandler()
+        {
+            @Override
+            public void handle(String target, Request jettyRequest, HttpServletRequest request, HttpServletResponse response)
+            {
+                jettyRequest.setHandled(true);
+                handlerLatch.countDown();
+            }
+        });
+
+        // Remove existing ErrorHandlers.
+        while (true)
+        {
+            ErrorHandler errorHandler = server.getBean(ErrorHandler.class);
+            if (errorHandler == null)
+                break;
+            server.removeBean(errorHandler);
+        }
+
+        server.addBean(new ErrorHandler()
+        {
+            @Override
+            public ByteBuffer badMessageError(int status, String reason, HttpFields.Mutable fields)
+            {
+                // TODO: flow control should be enough.
+                // Return a very large buffer that will cause HTTP/2 flow control exhaustion and/or TCP congestion.
+                return ByteBuffer.allocateDirect(128 * 1024 * 1024);
+            }
+        });
+
+        ByteBufferPool byteBufferPool = connector.getByteBufferPool();
+        Generator generator = new Generator(byteBufferPool);
+
+        // Craft a request with a bad URI, it will not hit the Handler.
+        MetaData.Request metaData1 = new MetaData.Request(
+            HttpMethod.GET.asString(),
+            HttpScheme.HTTP.asString(),
+            new HostPortHttpField("localhost:" + connector.getLocalPort()),
+            // Use an ambiguous path parameter so that the URI is invalid.
+            "/foo/..;/bar",
+            HttpVersion.HTTP_2,
+            HttpFields.EMPTY,
+            -1
+        );
+        ByteBufferPool.Lease lease = new ByteBufferPool.Lease(byteBufferPool);
+        generator.control(lease, new PrefaceFrame());
+        generator.control(lease, new SettingsFrame(new HashMap<>(), false));
+        generator.control(lease, new HeadersFrame(1, metaData1, null, true));
+
+        try (Socket client = new Socket("localhost", connector.getLocalPort()))
+        {
+            OutputStream output = client.getOutputStream();
+            for (ByteBuffer buffer : lease.getByteBuffers())
+            {
+                output.write(BufferUtil.toArray(buffer));
+            }
+
+            // Wait for the first request be processed on the server.
+            Thread.sleep(1000);
+
+            // Send a second request and verify that it hits the Handler.
+            lease.recycle();
+            MetaData.Request metaData2 = new MetaData.Request(
+                HttpMethod.GET.asString(),
+                HttpScheme.HTTP.asString(),
+                new HostPortHttpField("localhost:" + connector.getLocalPort()),
+                "/valid",
+                HttpVersion.HTTP_2,
+                HttpFields.EMPTY,
+                -1
+            );
+            generator.control(lease, new HeadersFrame(3, metaData2, null, true));
+            for (ByteBuffer buffer : lease.getByteBuffers())
+            {
+                output.write(BufferUtil.toArray(buffer));
+            }
+            assertTrue(handlerLatch.await(5, TimeUnit.SECONDS));
+        }
+    }
+}