1/*
2 * Copyright (c) 2013, 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
26package sun.net;
27
28import java.security.AccessController;
29
30/**
31 * Determines the ephemeral port range in use on this system.
32 * If this cannot be determined, then the default settings
33 * of the OS are returned.
34 */
35
36public final class PortConfig {
37
38    private static int defaultUpper, defaultLower;
39    private static final int upper, lower;
40
41    private PortConfig() {}
42
43    static {
44        AccessController.doPrivileged(
45            new java.security.PrivilegedAction<>() {
46                public Void run() {
47                    System.loadLibrary("net");
48                    String os = System.getProperty("os.name");
49                    if (os.startsWith("Linux")) {
50                        defaultLower = 32768;
51                        defaultUpper = 61000;
52                    } else if (os.startsWith("SunOS")) {
53                        defaultLower = 32768;
54                        defaultUpper = 65535;
55                    } else if (os.contains("OS X")) {
56                        defaultLower = 49152;
57                        defaultUpper = 65535;
58                    } else if (os.startsWith("AIX")) {
59                        // The ephemeral port is OS version dependent on AIX:
60                        // http://publib.boulder.ibm.com/infocenter/aix/v7r1/topic/com.ibm.aix.rsct315.admin/bl503_ephport.htm
61                        // However, on AIX 5.3 / 6.1 / 7.1 we always see the
62                        // settings below by using:
63                        // /usr/sbin/no -a | fgrep ephemeral
64                        defaultLower = 32768;
65                        defaultUpper = 65535;
66                    } else {
67                        throw new InternalError(
68                            "sun.net.PortConfig: unknown OS");
69                    }
70                    return null;
71                }
72            });
73
74        int v = getLower0();
75        if (v == -1) {
76            v = defaultLower;
77        }
78        lower = v;
79
80        v = getUpper0();
81        if (v == -1) {
82            v = defaultUpper;
83        }
84        upper = v;
85    }
86
87    static native int getLower0();
88    static native int getUpper0();
89
90    public static int getLower() {
91        return lower;
92    }
93
94    public static int getUpper() {
95        return upper;
96    }
97}
98