1 /*

     2  * Copyright (c) 2002, 2018, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  */

    23 

    24 import javax.naming.CommunicationException;

    25 import javax.naming.Context;

    26 import javax.naming.directory.InitialDirContext;

    27 

    28 /*

    29  * @test

    30  * @bug 8200151

    31  * @summary Tests that when a DNS server is unreachable and an ICMP Destination

    32  *          Unreachable packet is received, we fail quickly and don't wait for

    33  *          the full timeout interval. This could be caused, for example, by a

    34  *          dead DNS server or a flakey router.

    35  * @library ../lib/

    36  * @modules java.base/sun.security.util

    37  * @run main PortUnreachable

    38  */

    39 

    40 public class PortUnreachable extends DNSTestBase {

    41 

    42     // Port 25 is the SMTP port, used here to simulate a dead DNS server.

    43     private static final int PORT = 25;

    44 

    45     // Threshold in ms for elapsed time of request failed. Normally, it should

    46     // be very quick, but consider to different platform and test machine

    47     // performance, here we define 1000 ms as threshold which acceptable for

    48     // this test.

    49     private static final int THRESHOLD = 1000;

    50 

    51     private long startTime;

    52 

    53     public PortUnreachable() {

    54         setLocalServer(false);

    55     }

    56 

    57     public static void main(String[] args) throws Exception {

    58         new PortUnreachable().run(args);

    59     }

    60 

    61     /*

    62      * Tests that when a DNS server is unreachable and an ICMP Destination

    63      * Unreachable packet is received, we fail quickly and don't wait for

    64      * the full timeout interval.

    65      */

    66     @Override

    67     public void runTest() throws Exception {

    68         String deadServerUrl = "dns://localhost:" + PORT;

    69         env().put(Context.PROVIDER_URL, deadServerUrl);

    70         setContext(new InitialDirContext(env()));

    71 

    72         // Any request should fail quickly.

    73         startTime = System.currentTimeMillis();

    74         context().getAttributes("");

    75 

    76         // You're running a DNS server on your SMTP port?

    77         throw new RuntimeException(

    78                 "Failed: getAttributes succeeded unexpectedly");

    79     }

    80 

    81     @Override

    82     public boolean handleException(Exception e) {

    83         if (e instanceof CommunicationException) {

    84             long elapsedTime = System.currentTimeMillis() - startTime;

    85 

    86             Throwable cause = ((CommunicationException) e).getRootCause();

    87             if (!(cause instanceof java.net.PortUnreachableException)) {

    88                 DNSTestUtils.debug("Bug 7164518 can cause this failure on mac");

    89                 return false;

    90             }

    91 

    92             DNSTestUtils.debug("Elapsed (ms):  " + elapsedTime);

    93 

    94             // Check that elapsed time is less than defined threshold.

    95             if (elapsedTime < THRESHOLD) {

    96                 return true;

    97             }

    98 

    99             throw new RuntimeException("Failed: call took " + elapsedTime

   100                     + " ms, expected less than " + THRESHOLD + " ms");

   101         }

   102 

   103         return super.handleException(e);

   104     }

   105 }