1 /*

     2  * Copyright (c) 2000, 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.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

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

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

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

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

    15  * accompanied this code).

    16  *

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

    18  * 2 along with this work; if not, write to the Free Software Foundation,

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

    20  *

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

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

    23  * questions.

    24  */

    25 

    26 package sun.nio.ch;

    27 

    28 import java.io.FileDescriptor;

    29 import java.io.IOException;

    30 import java.net.InetSocketAddress;

    31 import java.net.ServerSocket;

    32 import java.net.SocketAddress;

    33 import java.net.SocketOption;

    34 import java.net.SocketTimeoutException;

    35 import java.net.StandardSocketOptions;

    36 import java.nio.channels.AlreadyBoundException;

    37 import java.nio.channels.AsynchronousCloseException;

    38 import java.nio.channels.ClosedChannelException;

    39 import java.nio.channels.IllegalBlockingModeException;

    40 import java.nio.channels.NotYetBoundException;

    41 import java.nio.channels.SelectionKey;

    42 import java.nio.channels.ServerSocketChannel;

    43 import java.nio.channels.SocketChannel;

    44 import java.nio.channels.spi.SelectorProvider;

    45 import java.util.Collections;

    46 import java.util.HashSet;

    47 import java.util.Objects;

    48 import java.util.Set;

    49 import java.util.concurrent.locks.ReentrantLock;

    50 

    51 import sun.net.NetHooks;

    52 import sun.net.ext.ExtendedSocketOptions;

    53 

    54 /**

    55  * An implementation of ServerSocketChannels

    56  */

    57 

    58 class InetServerSocketChannelImpl

    59     extends ServerSocketChannelImpl

    60 {

    61     // set true when exclusive binding is on and SO_REUSEADDR is emulated

    62     private boolean isReuseAddress;

    63 

    64     // Our socket adaptor, if any

    65     private ServerSocket socket;

    66 

    67     // -- End of fields protected by stateLock

    68 

    69 

    70     InetServerSocketChannelImpl(SelectorProvider sp) throws IOException {

    71         super(sp, Net.serverSocket(true));

    72     }

    73 

    74     InetServerSocketChannelImpl(SelectorProvider sp, FileDescriptor fd, boolean bound)

    75         throws IOException

    76     {

    77         super(sp, fd);

    78         if (bound) {

    79             synchronized (stateLock) {

    80                 localAddress = Net.localAddress(fd);

    81             }

    82         }

    83     }

    84 

    85     @Override

    86     public ServerSocket socket() {

    87         synchronized (stateLock) {

    88             if (socket == null)

    89                 socket = ServerSocketAdaptor.create(this);

    90             return socket;

    91         }

    92     }

    93 

    94     @Override

    95     public <T> ServerSocketChannel setOption(SocketOption<T> name, T value)

    96         throws IOException

    97     {

    98         Objects.requireNonNull(name);

    99         if (!supportedOptions().contains(name))

   100             throw new UnsupportedOperationException("'" + name + "' not supported");

   101         if (!name.type().isInstance(value))

   102             throw new IllegalArgumentException("Invalid value '" + value + "'");

   103 

   104         synchronized (stateLock) {

   105             ensureOpen();

   106 

   107             if (name == StandardSocketOptions.SO_REUSEADDR && Net.useExclusiveBind()) {

   108                 // SO_REUSEADDR emulated when using exclusive bind

   109                 isReuseAddress = (Boolean)value;

   110             } else {

   111                 // no options that require special handling

   112                 Net.setSocketOption(fd, Net.UNSPEC, name, value);

   113             }

   114             return this;

   115         }

   116     }

   117 

   118     @Override

   119     @SuppressWarnings("unchecked")

   120     public <T> T getOption(SocketOption<T> name)

   121         throws IOException

   122     {

   123         Objects.requireNonNull(name);

   124         if (!supportedOptions().contains(name))

   125             throw new UnsupportedOperationException("'" + name + "' not supported");

   126 

   127         synchronized (stateLock) {

   128             ensureOpen();

   129             if (name == StandardSocketOptions.SO_REUSEADDR && Net.useExclusiveBind()) {

   130                 // SO_REUSEADDR emulated when using exclusive bind

   131                 return (T)Boolean.valueOf(isReuseAddress);

   132             }

   133             // no options that require special handling

   134             return (T) Net.getSocketOption(fd, Net.UNSPEC, name);

   135         }

   136     }

   137 

   138     private static class DefaultOptionsHolder {

   139         static final Set<SocketOption<?>> defaultOptions = defaultOptions();

   140 

   141         private static Set<SocketOption<?>> defaultOptions() {

   142             HashSet<SocketOption<?>> set = new HashSet<>();

   143             set.add(StandardSocketOptions.SO_RCVBUF);

   144             set.add(StandardSocketOptions.SO_REUSEADDR);

   145             if (Net.isReusePortAvailable()) {

   146                 set.add(StandardSocketOptions.SO_REUSEPORT);

   147             }

   148             set.addAll(ExtendedSocketOptions.serverSocketOptions());

   149             return Collections.unmodifiableSet(set);

   150         }

   151     }

   152 

   153     @Override

   154     public final Set<SocketOption<?>> supportedOptions() {

   155         return DefaultOptionsHolder.defaultOptions;

   156     }

   157 

   158     @Override

   159     public ServerSocketChannel bind(SocketAddress local, int backlog) throws IOException {

   160         synchronized (stateLock) {

   161             ensureOpen();

   162             if (localAddress != null)

   163                 throw new AlreadyBoundException();

   164             InetSocketAddress isa = (local == null)

   165                                     ? new InetSocketAddress(0)

   166                                     : Net.checkAddress(local);

   167             SecurityManager sm = System.getSecurityManager();

   168             if (sm != null)

   169                 sm.checkListen(isa.getPort());

   170             NetHooks.beforeTcpBind(fd, isa.getAddress(), isa.getPort());

   171             Net.bind(fd, isa.getAddress(), isa.getPort());

   172             Net.listen(fd, backlog < 1 ? 50 : backlog);

   173             localAddress = Net.localAddress(fd);

   174         }

   175         return this;

   176     }

   177 

   178     protected int implAccept(FileDescriptor fd, FileDescriptor newfd, SocketAddress[] addrs)

   179         throws IOException

   180     {

   181         InetSocketAddress[] a = new InetSocketAddress[1];

   182         int n = Net.accept(fd, newfd, a);

   183         addrs[0] = a[0];

   184         return n;

   185     }

   186 

   187     protected SocketAddress getRevealedLocalAddress(SocketAddress addr) {

   188         return Net.getRevealedLocalAddress((InetSocketAddress)addr);

   189     }

   190 

   191     protected String getRevealedLocalAddressAsString(SocketAddress addr) {

   192         return Net.getRevealedLocalAddressAsString((InetSocketAddress)addr);

   193     }

   194 

   195 

   196     protected SocketChannel finishAccept(FileDescriptor newfd, SocketAddress sa)

   197         throws IOException

   198     {

   199         InetSocketAddress isa = (InetSocketAddress)sa;

   200         try {

   201             // newly accepted socket is initially in blocking mode

   202             IOUtil.configureBlocking(newfd, true);

   203 

   204             // check permitted to accept connections from the remote address

   205             SecurityManager sm = System.getSecurityManager();

   206             if (sm != null) {

   207                 sm.checkAccept(isa.getAddress().getHostAddress(), isa.getPort());

   208             }

   209             return new InetSocketChannelImpl(provider(), newfd, isa);

   210         } catch (Exception e) {

   211             nd.close(newfd);

   212             throw e;

   213         }

   214     }

   215 }