1 /*
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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
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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
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22  */
23 
24 /*
25  * @test
26  * @bug 7162687 8015595 8194486
27  * @summary enhance KDC server availability detection
28  * @library /test/lib
29  * @compile -XDignore.symbol.file Unreachable.java
30  * @run main jdk.test.lib.FileInstaller TestHosts TestHosts
31  * @run main/othervm -Djdk.net.hosts.file=TestHosts Unreachable
32  */
33 import java.net.PortUnreachableException;
34 import java.net.SocketTimeoutException;
35 import java.net.DatagramPacket;
36 import java.net.DatagramSocket;
37 import java.net.InetSocketAddress;
38 import java.util.concurrent.Callable;
39 import java.util.concurrent.ExecutorService;
40 import java.util.concurrent.Future;
41 import java.util.concurrent.TimeUnit;
42 import java.util.concurrent.TimeoutException;
43 import java.util.concurrent.Executors;
44 import javax.security.auth.login.LoginException;
45 import sun.security.krb5.Config;
46 
47 public class Unreachable {
48 
49     // Wait for 20 second until unreachable KDC throws PortUnreachableException.
50     private static final int TIMEOUT = 20;
51     private static final String REALM = "RABBIT.HOLE";
52     private static final String HOST = "127.0.0.1";
53     private static final int PORT = 13434;
54     private static final String KRB_CONF = "unreachable.krb5.conf";
55 
main(String[] args)56     public static void main(String[] args) throws Exception {
57 
58         // - Only PortUnreachableException will allow to continue execution.
59         // - SocketTimeoutException may occur on Mac because it will not throw
60         // PortUnreachableException for unreachable port in which case the Test
61         // execution will be skipped.
62         // - For Reachable port, the Test execution will get skipped.
63         // - Any other Exception will be treated as Test failure.
64         if (!findPortUnreachableExc()) {
65             System.out.println(String.format("WARNING: Either a reachable "
66                     + "connection found to %s:%s or SocketTimeoutException "
67                     + "occured which means PortUnreachableException not thrown"
68                     + " by the platform.", HOST, PORT));
69             return;
70         }
71         KDC kdc = KDC.existing(REALM, HOST, PORT);
72         KDC.saveConfig(KRB_CONF, kdc);
73         ExecutorService executor = Executors.newSingleThreadExecutor();
74         Future<Exception> future = executor.submit(new Callable<Exception>() {
75             @Override
76             public Exception call() {
77                 System.setProperty("java.security.krb5.conf", KRB_CONF);
78                 try {
79                     Config.refresh();
80                     // If PortUnreachableException is not received, the login
81                     // will consume about 3*3*30 seconds and the test will
82                     // timeout.
83                     try {
84                         Context.fromUserPass("name", "pass".toCharArray(), true);
85                     } catch (LoginException le) {
86                         // This is OK
87                     }
88                     System.out.println("Execution successful.");
89                 } catch (Exception e) {
90                     return e;
91                 }
92                 return null;
93             }
94         });
95         try {
96             Exception ex = null;
97             if ((ex = future.get(TIMEOUT, TimeUnit.SECONDS)) != null) {
98                 throw new RuntimeException(ex);
99             }
100         } catch (TimeoutException e) {
101             future.cancel(true);
102             throw new RuntimeException("PortUnreachableException not thrown.");
103         } finally {
104             executor.shutdownNow();
105         }
106     }
107 
108     /**
109      * If the remote destination to which the socket is connected does not
110      * exist, or is otherwise unreachable, and if an ICMP destination unreachable
111      * packet has been received for that address, then a subsequent call to
112      * send or receive may throw a PortUnreachableException. Note, there is no
113      * guarantee that the exception will be thrown.
114      */
findPortUnreachableExc()115     private static boolean findPortUnreachableExc() throws Exception {
116         try {
117             InetSocketAddress iaddr = new InetSocketAddress(HOST, PORT);
118             DatagramSocket dgSocket = new DatagramSocket();
119             dgSocket.setSoTimeout(5000);
120             dgSocket.connect(iaddr);
121             byte[] data = new byte[]{};
122             dgSocket.send(new DatagramPacket(data, data.length, iaddr));
123             dgSocket.receive(new DatagramPacket(data, data.length));
124         } catch (PortUnreachableException e) {
125             return true;
126         } catch (SocketTimeoutException e) {
127             return false;
128         }
129         return false;
130     }
131 }
132