--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/java/net/httpclient/ForbiddenHeadTest.java	Wed May 20 18:57:06 2020 +0100
@@ -0,0 +1,465 @@
+/*
+ * Copyright (c) 2020, Oracle and/or its affiliates. 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.
+ *
+ * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @summary checks that receiving 403 for a HEAD request after
+ *          401/407 doesn't cause any unexpected behavior.
+ * @modules java.base/sun.net.www.http
+ *          java.net.http/jdk.internal.net.http.common
+ *          java.net.http/jdk.internal.net.http.frame
+ *          java.net.http/jdk.internal.net.http.hpack
+ *          java.logging
+ *          jdk.httpserver
+ *          java.base/sun.net.www.http
+ *          java.base/sun.net.www
+ *          java.base/sun.net
+ * @library /test/lib http2/server
+ * @build HttpServerAdapters DigestEchoServer Http2TestServer ForbiddenHeadTest
+ * @build jdk.test.lib.net.SimpleSSLContext
+ * @run testng/othervm
+ *       -Djdk.http.auth.tunneling.disabledSchemes
+ *       -Djdk.httpclient.HttpClient.log=headers,requests
+ *       -Djdk.internal.httpclient.debug=true
+ *       ForbiddenHeadTest
+ */
+
+import com.sun.net.httpserver.HttpServer;
+import com.sun.net.httpserver.HttpsConfigurator;
+import com.sun.net.httpserver.HttpsServer;
+import jdk.test.lib.net.SimpleSSLContext;
+import org.testng.ITestContext;
+import org.testng.annotations.AfterClass;
+import org.testng.annotations.AfterTest;
+import org.testng.annotations.BeforeMethod;
+import org.testng.annotations.BeforeTest;
+import org.testng.annotations.DataProvider;
+import org.testng.annotations.Test;
+
+import javax.net.ssl.SSLContext;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.Authenticator;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.PasswordAuthentication;
+import java.net.Proxy;
+import java.net.ProxySelector;
+import java.net.SocketAddress;
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.net.http.HttpResponse.BodyHandlers;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+import java.util.concurrent.atomic.AtomicLong;
+
+import static java.lang.System.err;
+import static java.lang.System.out;
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static org.testng.Assert.assertEquals;
+import static org.testng.Assert.assertNotNull;
+
+public class ForbiddenHeadTest implements HttpServerAdapters {
+
+    SSLContext sslContext;
+    HttpTestServer httpTestServer;        // HTTP/1.1
+    HttpTestServer httpsTestServer;       // HTTPS/1.1
+    HttpTestServer http2TestServer;       // HTTP/2 ( h2c )
+    HttpTestServer https2TestServer;      // HTTP/2 ( h2  )
+    DigestEchoServer.TunnelingProxy proxy;
+    DigestEchoServer.TunnelingProxy authproxy;
+    String httpURI;
+    String httpsURI;
+    String http2URI;
+    String https2URI;
+    HttpClient authClient;
+    HttpClient noAuthClient;
+
+    final ReferenceTracker TRACKER = ReferenceTracker.INSTANCE;
+    static final long SLEEP_AFTER_TEST = 0; // milliseconds
+    static final int ITERATIONS = 3;
+    static final Executor executor = new TestExecutor(Executors.newCachedThreadPool());
+    static final ConcurrentMap<String, Throwable> FAILURES = new ConcurrentHashMap<>();
+    static volatile boolean tasksFailed;
+    static final AtomicLong serverCount = new AtomicLong();
+    static final AtomicLong clientCount = new AtomicLong();
+    static final long start = System.nanoTime();
+    public static String now() {
+        long now = System.nanoTime() - start;
+        long secs = now / 1000_000_000;
+        long mill = (now % 1000_000_000) / 1000_000;
+        long nan = now % 1000_000;
+        return String.format("[%d s, %d ms, %d ns] ", secs, mill, nan);
+    }
+
+    static class TestExecutor implements Executor {
+        final AtomicLong tasks = new AtomicLong();
+        Executor executor;
+        TestExecutor(Executor executor) {
+            this.executor = executor;
+        }
+
+        @Override
+        public void execute(Runnable command) {
+            long id = tasks.incrementAndGet();
+            executor.execute(() -> {
+                try {
+                    command.run();
+                } catch (Throwable t) {
+                    tasksFailed = true;
+                    out.printf(now() + "Task %s failed: %s%n", id, t);
+                    err.printf(now() + "Task %s failed: %s%n", id, t);
+                    FAILURES.putIfAbsent("Task " + id, t);
+                    throw t;
+                }
+            });
+        }
+    }
+
+    protected boolean stopAfterFirstFailure() {
+        return Boolean.getBoolean("jdk.internal.httpclient.debug");
+    }
+
+    @BeforeMethod
+    void beforeMethod(ITestContext context) {
+        if (stopAfterFirstFailure() && context.getFailedTests().size() > 0) {
+            throw new RuntimeException("some tests failed");
+        }
+    }
+
+    @AfterClass
+    static final void printFailedTests() {
+        out.println("\n=========================");
+        try {
+            out.printf("%n%sCreated %d servers and %d clients%n",
+                    now(), serverCount.get(), clientCount.get());
+            if (FAILURES.isEmpty()) return;
+            out.println("Failed tests: ");
+            FAILURES.entrySet().forEach((e) -> {
+                out.printf("\t%s: %s%n", e.getKey(), e.getValue());
+                e.getValue().printStackTrace(out);
+                e.getValue().printStackTrace();
+            });
+            if (tasksFailed) {
+                out.println("WARNING: Some tasks failed");
+            }
+        } finally {
+            out.println("\n=========================\n");
+        }
+    }
+
+    static final int UNAUTHORIZED = 401;
+    static final int PROXY_UNAUTHORIZED = 407;
+    static final int FORBIDDEN = 403;
+    static final int HTTP_OK = 200;
+    static final String MESSAGE = "Unauthorized";
+
+
+    @DataProvider(name = "all")
+    public Object[][] allcases() {
+        List<Object[]> result = new ArrayList<>();
+        for (var client : List.of(authClient, noAuthClient)) {
+            for (boolean async : List.of(true, false)) {
+                for (int code : List.of(UNAUTHORIZED, PROXY_UNAUTHORIZED)) {
+                    var srv = code == PROXY_UNAUTHORIZED ? "/proxy" : "/server";
+                    for (var auth : List.of("/auth", "/noauth")) {
+                        var pcode = code;
+                        if (auth.equals("/noauth")) {
+                            if (client == authClient) continue;
+                            pcode = FORBIDDEN;
+                        }
+                        for (var uri : List.of(httpURI, httpsURI, http2URI, https2URI)) {
+                            result.add(new Object[]{uri + srv + auth, pcode, async, client});
+                        }
+                    }
+                }
+            }
+        }
+        return result.toArray(new Object[0][0]);
+    }
+
+    static final AtomicLong requestCounter = new AtomicLong();
+
+    static final Authenticator authenticator = new Authenticator() {
+        @Override
+        protected PasswordAuthentication getPasswordAuthentication() {
+            return new PasswordAuthentication("arthur",new char[] {'d', 'e', 'n', 't'});
+        }
+    };
+
+    static final AtomicLong sleepCount = new AtomicLong();
+
+    @Test(dataProvider = "all")
+    void test(String uriString, int code, boolean async, HttpClient client) throws Throwable {
+        var name = String.format("test(%s, %d, %s, %s)", uriString, code, async ? "async" : "sync",
+                client.authenticator().isPresent() ? "authClient" : "noAuthClient");
+        out.printf("%n---- starting %s ----%n", name);
+        assert client.authenticator().isPresent() ? client == authClient : client == noAuthClient;
+        uriString = uriString + "/ForbiddenTest";
+        for (int i=0; i<ITERATIONS; i++) {
+            if (ITERATIONS > 1) out.printf("---- ITERATION %d%n",i);
+            try {
+                doTest(uriString, code, async, client);
+                long count = sleepCount.incrementAndGet();
+                System.err.println(now() + " Sleeping: " + count);
+                Thread.sleep(SLEEP_AFTER_TEST);
+                System.err.println(now() + " Waking up: " + count);
+            } catch (Throwable x) {
+                FAILURES.putIfAbsent(name, x);
+                throw x;
+            }
+        }
+    }
+
+    static String authHeaderName(int code) {
+        return switch (code) {
+            case UNAUTHORIZED -> "WWW-Authenticate";
+            case PROXY_UNAUTHORIZED -> "Proxy-Authenticate";
+            default -> null;
+        };
+    }
+
+    private void doTest(String uriString, int code, boolean async, HttpClient client) throws Throwable {
+        URI uri = URI.create(uriString);
+
+        HttpRequest.Builder requestBuilder = HttpRequest
+                .newBuilder(uri)
+                .method("HEAD", HttpRequest.BodyPublishers.noBody());
+
+        HttpRequest request = requestBuilder.build();
+        out.println("Initial request: " + request.uri());
+
+        String header = authHeaderName(code);
+        // the request is expected to return 403 Forbidden if the client is authenticated,
+        // or the server doesn't require authentication, 401 or 407 otherwise.
+        boolean forbidden = client.authenticator().isPresent() || code == FORBIDDEN;
+
+        HttpResponse<String> response = null;
+        if (async) {
+            response = client.send(request, BodyHandlers.ofString());
+        } else {
+           try {
+               response = client.sendAsync(request, BodyHandlers.ofString()).get();
+           } catch (ExecutionException ex) {
+               throw ex.getCause();
+           }
+        }
+
+        String prefix = uriString.contains("/proxy/") ? "Proxy-" : "WWW-";
+        String expectedValue;
+        if (forbidden) {
+            // The message body is generated by the server, after authentication was
+            // successful.
+            expectedValue =  prefix + "FORBIDDEN";
+        } else if (uriString.contains("/proxy/") && uri.getScheme().equalsIgnoreCase("https")) {
+            // In that case the tunnelling proxy itself is expected to return 407,
+            // and the message will have no body (since the CONNECT request fails).
+            assert code == PROXY_UNAUTHORIZED;
+            expectedValue = null;
+        } else {
+            // the message body is generated by our fake server pretending to be
+            // a proxy.
+            expectedValue = prefix + MESSAGE;
+        }
+
+
+        out.println("  Got response: " + response);
+        assertEquals(response.statusCode(), forbidden? FORBIDDEN : code);
+        assertEquals(response.body(), expectedValue == null ? null : "");
+        assertEquals(response.headers().firstValue("X-value"), Optional.ofNullable(expectedValue));
+        // when the CONNECT request fails, its body is discarded - but
+        // the response header may still contain its content length.
+        // don't check content length in that case.
+        if (expectedValue != null) {
+            String clen = String.valueOf(expectedValue.getBytes(UTF_8).length);
+            assertEquals(response.headers().firstValue("Content-Length"), Optional.of(clen));
+        }
+
+    }
+
+    // -- Infrastructure
+
+    @BeforeTest
+    public void setup() throws Exception {
+        sslContext = new SimpleSSLContext().get();
+        if (sslContext == null)
+            throw new AssertionError("Unexpected null sslContext");
+
+        InetSocketAddress sa = new InetSocketAddress(InetAddress.getLoopbackAddress(), 0);
+
+        httpTestServer = HttpTestServer.of(HttpServer.create(sa, 0));
+        httpTestServer.addHandler(new UnauthorizedHandler(), "/http1/");
+        httpTestServer.addHandler(new UnauthorizedHandler(), "/http2/proxy/");
+        httpURI = "http://" + httpTestServer.serverAuthority() + "/http1";
+        HttpsServer httpsServer = HttpsServer.create(sa, 0);
+        httpsServer.setHttpsConfigurator(new HttpsConfigurator(sslContext));
+        httpsTestServer = HttpTestServer.of(httpsServer);
+        httpsTestServer.addHandler(new UnauthorizedHandler(),"/https1/");
+        httpsURI = "https://" + httpsTestServer.serverAuthority() + "/https1";
+
+        http2TestServer = HttpTestServer.of(new Http2TestServer("localhost", false, 0));
+        http2TestServer.addHandler(new UnauthorizedHandler(), "/http2/");
+        http2URI = "http://" + http2TestServer.serverAuthority() + "/http2";
+        https2TestServer = HttpTestServer.of(new Http2TestServer("localhost", true, sslContext));
+        https2TestServer.addHandler(new UnauthorizedHandler(), "/https2/");
+        https2URI = "https://" + https2TestServer.serverAuthority() + "/https2";
+
+        proxy = DigestEchoServer.createHttpsProxyTunnel(DigestEchoServer.HttpAuthSchemeType.NONE);
+        authproxy = DigestEchoServer.createHttpsProxyTunnel(DigestEchoServer.HttpAuthSchemeType.BASIC);
+
+        authClient = TRACKER.track(HttpClient.newBuilder()
+                .proxy(TestProxySelector.of(proxy, authproxy, httpTestServer))
+                .sslContext(sslContext)
+                .executor(executor)
+                .authenticator(authenticator)
+                .build());
+        clientCount.incrementAndGet();
+
+        noAuthClient = TRACKER.track(HttpClient.newBuilder()
+                .proxy(TestProxySelector.of(proxy, authproxy, httpTestServer))
+                .sslContext(sslContext)
+                .executor(executor)
+                .build());
+        clientCount.incrementAndGet();
+
+        httpTestServer.start();
+        serverCount.incrementAndGet();
+        httpsTestServer.start();
+        serverCount.incrementAndGet();
+        http2TestServer.start();
+        serverCount.incrementAndGet();
+        https2TestServer.start();
+        serverCount.incrementAndGet();
+    }
+
+    @AfterTest
+    public void teardown() throws Exception {
+        authClient = noAuthClient = null;
+        Thread.sleep(100);
+        AssertionError fail = TRACKER.check(500);
+
+        proxy.stop();
+        authproxy.stop();
+        httpTestServer.stop();
+        httpsTestServer.stop();
+        http2TestServer.stop();
+        https2TestServer.stop();
+    }
+
+    static class TestProxySelector extends ProxySelector {
+        final DigestEchoServer.TunnelingProxy proxy;
+        final DigestEchoServer.TunnelingProxy authproxy;
+        final HttpTestServer plain;
+        private TestProxySelector(DigestEchoServer.TunnelingProxy proxy,
+                                  DigestEchoServer.TunnelingProxy authproxy,
+                                  HttpTestServer plain) {
+            this.proxy = proxy;
+            this.authproxy = authproxy;
+            this.plain = plain;
+        }
+        @Override
+        public List<Proxy> select(URI uri) {
+            String path = uri.getPath();
+            out.println("Selecting proxy for: " + uri);
+            if (path.contains("/proxy/")) {
+                if (path.contains("/http1/")) {
+                    // Simple proxying - in our test the server pretends
+                    // to be the proxy.
+                    System.out.print("PROXY is server for " + uri);
+                    return List.of(new Proxy(Proxy.Type.HTTP,
+                            new InetSocketAddress(uri.getHost(), uri.getPort())));
+                } else if (path.contains("/http2/")) {
+                    // HTTP/2 is downgraded to HTTP/1.1 if there is a proxy
+                    System.out.print("PROXY is plain server for " + uri);
+                    return List.of(new Proxy(Proxy.Type.HTTP, plain.getAddress()));
+                } else {
+                    // Both HTTPS or HTTPS/2 require tunnelling
+                    var p = path.contains("/auth/") ? authproxy : proxy;
+                    if (p == authproxy) {
+                        out.println("PROXY is authenticating tunneling proxy for " + uri);
+                    } else {
+                        out.println("PROXY is plain tunneling proxy for " + uri);
+                    }
+                    return List.of(new Proxy(Proxy.Type.HTTP, p.getProxyAddress()));
+                }
+            }
+            System.out.print("NO_PROXY for " + uri);
+            return List.of(Proxy.NO_PROXY);
+        }
+        @Override
+        public void connectFailed(URI uri, SocketAddress sa, IOException ioe) {
+            System.err.printf("Connect failed for: uri=\"%s\", sa=\"%s\", ioe=%s%n", uri, sa, ioe);
+        }
+        public static TestProxySelector of(DigestEchoServer.TunnelingProxy proxy,
+                                           DigestEchoServer.TunnelingProxy authproxy,
+                                           HttpTestServer plain) {
+            return new TestProxySelector(proxy, authproxy, plain);
+        }
+    }
+
+    static class UnauthorizedHandler implements HttpTestHandler {
+
+        @Override
+        public void handle(HttpTestExchange t) throws IOException {
+            readAllRequestData(t); // shouldn't be any
+            String method = t.getRequestMethod();
+            String path = t.getRequestURI().getPath();
+            HttpTestRequestHeaders  reqh = t.getRequestHeaders();
+            HttpTestResponseHeaders rsph = t.getResponseHeaders();
+
+            String xValue;
+            boolean noAuthRequired = path.contains("/noauth/");
+            boolean authenticated  = path.contains("/server/") && reqh.containsKey("Authorization")
+                    || path.contains("/proxy/") && reqh.containsKey("Proxy-Authorization")
+                    || path.contains("/proxy/") && (path.contains("/https1/") || path.contains("/https2/"));
+            String srv = path.contains("/proxy/") ? "proxy" : "server";
+            String prefix = path.contains("/proxy/") ? "Proxy-" : "WWW-";
+            int authcode = path.contains("/proxy/") ? PROXY_UNAUTHORIZED : UNAUTHORIZED;
+            int code = (authenticated || noAuthRequired) ? FORBIDDEN : authcode;
+            if (authenticated || noAuthRequired) {
+                xValue = prefix + "FORBIDDEN";
+            } else {
+                xValue = prefix + MESSAGE;
+                rsph.addHeader(prefix + "Authenticate", "Basic realm=\"earth\", charset=\"UTF-8\"");
+            }
+
+            t.getResponseHeaders().addHeader("X-value", xValue);
+            t.getResponseHeaders().addHeader("Content-Length", String.valueOf(xValue.getBytes(UTF_8).length));
+            t.sendResponseHeaders(code, 0);
+        }
+    }
+
+    static void readAllRequestData(HttpTestExchange t) throws IOException {
+        try (InputStream is = t.getRequestBody()) {
+            is.readAllBytes();
+        }
+    }
+}

--- a/test/jdk/java/net/httpclient/http2/server/Http2TestExchangeImpl.java	Wed May 20 15:56:39 2020 +0200
+++ b/test/jdk/java/net/httpclient/http2/server/Http2TestExchangeImpl.java	Wed May 20 18:57:06 2020 +0100
@@ -37,6 +37,7 @@
 
 public class Http2TestExchangeImpl implements Http2TestExchange {
 
+    static final String HEAD = "HEAD";
     final HttpHeaders reqheaders;
     final HttpHeadersBuilder rspheadersBuilder;
     final URI uri;
@@ -129,7 +130,7 @@
     @Override
     public void sendResponseHeaders(int rCode, long responseLength) throws IOException {
         this.responseLength = responseLength;
-        if (responseLength !=0 && rCode != 204) {
+        if (responseLength !=0 && rCode != 204 && !isHeadRequest()) {
                 long clen = responseLength > 0 ? responseLength : 0;
             rspheadersBuilder.setHeader("Content-length", Long.toString(clen));
         }
@@ -198,4 +199,8 @@
             System.err.println("TestServer: pushPromise exception: " + ex);
         }
     }
+
+    private boolean isHeadRequest() {
+        return HEAD.equalsIgnoreCase(getRequestMethod());
+    }
 }