1 /*

     2  * Copyright (c) 2019, 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 /* @test

    25  * @bug 8234805

    26  * @summary Test that DatagramChannel.receive returns the expected sender address

    27  * @run main ManySenders

    28  * @run main/othervm -Djava.net.preferIPv4Stack=true ManySenders

    29  */

    30 

    31 import java.io.ByteArrayInputStream;

    32 import java.io.ByteArrayOutputStream;

    33 import java.io.ObjectInputStream;

    34 import java.io.ObjectOutputStream;

    35 import java.net.InetAddress;

    36 import java.net.InetSocketAddress;

    37 import java.net.NetworkInterface;

    38 import java.net.SocketAddress;

    39 import java.nio.ByteBuffer;

    40 import java.nio.channels.DatagramChannel;

    41 import java.util.List;

    42 import java.util.stream.Collectors;

    43 import java.util.stream.Stream;

    44 

    45 public class ManySenders {

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

    47 

    48         // use addresses on interfaces that have the loopback and local host

    49         InetAddress lh = InetAddress.getLocalHost();

    50         InetAddress lb = InetAddress.getLoopbackAddress();

    51         List<InetAddress> addresses = Stream.concat(

    52                 NetworkInterface.getByInetAddress(lh).inetAddresses(),

    53                 NetworkInterface.getByInetAddress(lb).inetAddresses())

    54                 .filter(ia -> !ia.isAnyLocalAddress())

    55                 .distinct()

    56                 .collect(Collectors.toList());

    57 

    58         // bind DatagramChannel to wildcard address so it can receive from any address

    59         try (DatagramChannel reader = DatagramChannel.open()) {

    60             reader.bind(new InetSocketAddress(0));

    61             for (InetAddress address : addresses) {

    62                 System.out.format("%n-- %s --%n", address.getHostAddress());

    63 

    64                 // send 3 datagrams from the given address to the reader

    65                 test(3, address, reader);

    66             }

    67         }

    68     }

    69 

    70     static void test(int count, InetAddress address, DatagramChannel reader) throws Exception {

    71         int remotePort = reader.socket().getLocalPort();

    72         InetSocketAddress remote = new InetSocketAddress(address, remotePort);

    73 

    74         try (DatagramChannel sender = DatagramChannel.open()) {

    75             sender.bind(new InetSocketAddress(address, 0));

    76 

    77             SocketAddress local = sender.getLocalAddress();

    78             byte[] bytes = serialize(local);

    79 

    80             SocketAddress previousSource = null;

    81             for (int i = 0; i < count; i++) {

    82                 System.out.format("send %s -> %s%n", local, remote);

    83                 sender.send(ByteBuffer.wrap(bytes), remote);

    84 

    85                 ByteBuffer bb = ByteBuffer.allocate(1000);

    86                 SocketAddress source = reader.receive(bb);

    87                 System.out.format("received datagram from %s%n", source);

    88 

    89                 // check source address and payload

    90                 SocketAddress payload = deserialize(bb.array());

    91                 if (!source.equals(local))

    92                     throw new RuntimeException("source=" + source + ", expected=" + local);

    93                 if (!payload.equals(local))

    94                     throw new RuntimeException("payload=" + payload + ", expected=" + local);

    95 

    96                 // check that cached source was used

    97                 if (previousSource == null) {

    98                     previousSource = source;

    99                 } else if (source != previousSource) {

   100                     throw new RuntimeException("Cached SocketAddress not returned");

   101                 }

   102             }

   103         }

   104     }

   105 

   106     private static byte[] serialize(SocketAddress address) throws Exception {

   107         ByteArrayOutputStream baos = new ByteArrayOutputStream();

   108         ObjectOutputStream oos = new ObjectOutputStream(baos);

   109         oos.writeObject(address);

   110         oos.close();

   111         return baos.toByteArray();

   112     }

   113 

   114     private static SocketAddress deserialize(byte[] bytes) throws Exception {

   115         ByteArrayInputStream bais = new ByteArrayInputStream(bytes);

   116         ObjectInputStream ois = new ObjectInputStream(bais);

   117         return (SocketAddress) ois.readObject();

   118     }

   119 }