1 /*
2 * Copyright (c) 1995, 2014, 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 java.net;
27
28 import java.util.NavigableSet;
29 import java.util.Iterator;
30 import java.util.List;
31 import java.util.ArrayList;
32 import java.util.ServiceLoader;
33 import java.security.AccessController;
34 import java.io.ObjectStreamException;
35 import java.io.ObjectStreamField;
36 import java.io.IOException;
37 import java.io.ObjectInputStream;
38 import java.io.ObjectInputStream.GetField;
39 import java.io.ObjectOutputStream;
40 import java.io.ObjectOutputStream.PutField;
41 import java.util.concurrent.ConcurrentHashMap;
42 import java.util.concurrent.ConcurrentMap;
43 import java.util.concurrent.ConcurrentSkipListSet;
44 import java.util.concurrent.atomic.AtomicLong;
45
46 import sun.security.action.*;
47 import sun.net.InetAddressCachePolicy;
48 import sun.net.util.IPAddressUtil;
49 import sun.net.spi.nameservice.*;
50
51 /**
52 * This class represents an Internet Protocol (IP) address.
53 *
54 * <p> An IP address is either a 32-bit or 128-bit unsigned number
55 * used by IP, a lower-level protocol on which protocols like UDP and
56 * TCP are built. The IP address architecture is defined by <a
57 * href="http://www.ietf.org/rfc/rfc790.txt"><i>RFC 790:
58 * Assigned Numbers</i></a>, <a
59 * href="http://www.ietf.org/rfc/rfc1918.txt"> <i>RFC 1918:
60 * Address Allocation for Private Internets</i></a>, <a
61 * href="http://www.ietf.org/rfc/rfc2365.txt"><i>RFC 2365:
62 * Administratively Scoped IP Multicast</i></a>, and <a
63 * href="http://www.ietf.org/rfc/rfc2373.txt"><i>RFC 2373: IP
64 * Version 6 Addressing Architecture</i></a>. An instance of an
65 * InetAddress consists of an IP address and possibly its
66 * corresponding host name (depending on whether it is constructed
67 * with a host name or whether it has already done reverse host name
68 * resolution).
69 *
70 * <h3> Address types </h3>
71 *
72 * <blockquote><table cellspacing=2 summary="Description of unicast and multicast address types">
73 * <tr><th valign=top><i>unicast</i></th>
74 * <td>An identifier for a single interface. A packet sent to
75 * a unicast address is delivered to the interface identified by
76 * that address.
77 *
78 * <p> The Unspecified Address -- Also called anylocal or wildcard
79 * address. It must never be assigned to any node. It indicates the
80 * absence of an address. One example of its use is as the target of
81 * bind, which allows a server to accept a client connection on any
82 * interface, in case the server host has multiple interfaces.
83 *
84 * <p> The <i>unspecified</i> address must not be used as
85 * the destination address of an IP packet.
86 *
87 * <p> The <i>Loopback</i> Addresses -- This is the address
88 * assigned to the loopback interface. Anything sent to this
89 * IP address loops around and becomes IP input on the local
90 * host. This address is often used when testing a
91 * client.</td></tr>
92 * <tr><th valign=top><i>multicast</i></th>
93 * <td>An identifier for a set of interfaces (typically belonging
94 * to different nodes). A packet sent to a multicast address is
95 * delivered to all interfaces identified by that address.</td></tr>
96 * </table></blockquote>
97 *
98 * <h4> IP address scope </h4>
99 *
100 * <p> <i>Link-local</i> addresses are designed to be used for addressing
101 * on a single link for purposes such as auto-address configuration,
102 * neighbor discovery, or when no routers are present.
103 *
104 * <p> <i>Site-local</i> addresses are designed to be used for addressing
105 * inside of a site without the need for a global prefix.
106 *
107 * <p> <i>Global</i> addresses are unique across the internet.
108 *
109 * <h4> Textual representation of IP addresses </h4>
110 *
111 * The textual representation of an IP address is address family specific.
112 *
113 * <p>
114 *
115 * For IPv4 address format, please refer to <A
116 * HREF="Inet4Address.html#format">Inet4Address#format</A>; For IPv6
117 * address format, please refer to <A
118 * HREF="Inet6Address.html#format">Inet6Address#format</A>.
119 *
120 * <P>There is a <a href="doc-files/net-properties.html#Ipv4IPv6">couple of
121 * System Properties</a> affecting how IPv4 and IPv6 addresses are used.</P>
122 *
123 * <h4> Host Name Resolution </h4>
124 *
125 * Host name-to-IP address <i>resolution</i> is accomplished through
126 * the use of a combination of local machine configuration information
127 * and network naming services such as the Domain Name System (DNS)
128 * and Network Information Service(NIS). The particular naming
129 * services(s) being used is by default the local machine configured
130 * one. For any host name, its corresponding IP address is returned.
131 *
132 * <p> <i>Reverse name resolution</i> means that for any IP address,
133 * the host associated with the IP address is returned.
134 *
135 * <p> The InetAddress class provides methods to resolve host names to
136 * their IP addresses and vice versa.
137 *
138 * <h4> InetAddress Caching </h4>
139 *
140 * The InetAddress class has a cache to store successful as well as
141 * unsuccessful host name resolutions.
142 *
143 * <p> By default, when a security manager is installed, in order to
144 * protect against DNS spoofing attacks,
145 * the result of positive host name resolutions are
146 * cached forever. When a security manager is not installed, the default
147 * behavior is to cache entries for a finite (implementation dependent)
148 * period of time. The result of unsuccessful host
149 * name resolution is cached for a very short period of time (10
150 * seconds) to improve performance.
151 *
152 * <p> If the default behavior is not desired, then a Java security property
153 * can be set to a different Time-to-live (TTL) value for positive
154 * caching. Likewise, a system admin can configure a different
155 * negative caching TTL value when needed.
156 *
157 * <p> Two Java security properties control the TTL values used for
158 * positive and negative host name resolution caching:
159 *
160 * <blockquote>
161 * <dl>
162 * <dt><b>networkaddress.cache.ttl</b></dt>
163 * <dd>Indicates the caching policy for successful name lookups from
164 * the name service. The value is specified as an integer to indicate
165 * the number of seconds to cache the successful lookup. The default
166 * setting is to cache for an implementation specific period of time.
167 * <p>
168 * A value of -1 indicates "cache forever".
169 * </dd>
170 * <dt><b>networkaddress.cache.negative.ttl</b> (default: 10)</dt>
171 * <dd>Indicates the caching policy for un-successful name lookups
172 * from the name service. The value is specified as an integer to
173 * indicate the number of seconds to cache the failure for
174 * un-successful lookups.
175 * <p>
176 * A value of 0 indicates "never cache".
177 * A value of -1 indicates "cache forever".
178 * </dd>
179 * </dl>
180 * </blockquote>
181 *
182 * @author Chris Warth
183 * @see java.net.InetAddress#getByAddress(byte[])
184 * @see java.net.InetAddress#getByAddress(java.lang.String, byte[])
185 * @see java.net.InetAddress#getAllByName(java.lang.String)
186 * @see java.net.InetAddress#getByName(java.lang.String)
187 * @see java.net.InetAddress#getLocalHost()
188 * @since 1.0
189 */
190 public
191 class InetAddress implements java.io.Serializable {
192 /**
193 * Specify the address family: Internet Protocol, Version 4
194 * @since 1.4
195 */
196 static final int IPv4 = 1;
197
198 /**
199 * Specify the address family: Internet Protocol, Version 6
200 * @since 1.4
201 */
202 static final int IPv6 = 2;
203
204 /* Specify address family preference */
205 static transient boolean preferIPv6Address = false;
206
207 static class InetAddressHolder {
208
209 InetAddressHolder() {}
210
211 InetAddressHolder(String hostName, int address, int family) {
212 this.hostName = hostName;
213 this.address = address;
214 this.family = family;
215 }
216
217 void init(String hostName, int family) {
218 this.hostName = hostName;
219 if (family != -1) {
220 this.family = family;
221 }
222 }
223
224 String hostName;
225
226 String getHostName() {
227 return hostName;
228 }
229
230 /**
231 * Holds a 32-bit IPv4 address.
232 */
233 int address;
234
235 int getAddress() {
236 return address;
237 }
238
239 /**
240 * Specifies the address family type, for instance, '1' for IPv4
241 * addresses, and '2' for IPv6 addresses.
242 */
243 int family;
244
245 int getFamily() {
246 return family;
247 }
248 }
249
250 /* Used to store the serializable fields of InetAddress */
251 final transient InetAddressHolder holder;
252
253 InetAddressHolder holder() {
254 return holder;
255 }
256
257 /* Used to store the name service provider */
258 private static List<NameService> nameServices = null;
259
260 /* Used to store the best available hostname */
261 private transient String canonicalHostName = null;
262
263 /** use serialVersionUID from JDK 1.0.2 for interoperability */
264 private static final long serialVersionUID = 3286316764910316507L;
265
266 /*
267 * Load net library into runtime, and perform initializations.
268 */
269 static {
270 preferIPv6Address = java.security.AccessController.doPrivileged(
271 new GetBooleanAction("java.net.preferIPv6Addresses")).booleanValue();
272 AccessController.doPrivileged(
273 new java.security.PrivilegedAction<>() {
274 public Void run() {
275 System.loadLibrary("net");
276 return null;
277 }
278 });
279 init();
280 }
281
282 /**
283 * Constructor for the Socket.accept() method.
284 * This creates an empty InetAddress, which is filled in by
285 * the accept() method. This InetAddress, however, is not
286 * put in the address cache, since it is not created by name.
287 */
288 InetAddress() {
289 holder = new InetAddressHolder();
290 }
291
292 /**
293 * Replaces the de-serialized object with an Inet4Address object.
294 *
295 * @return the alternate object to the de-serialized object.
296 *
297 * @throws ObjectStreamException if a new object replacing this
298 * object could not be created
299 */
300 private Object readResolve() throws ObjectStreamException {
301 // will replace the deserialized 'this' object
302 return new Inet4Address(holder().getHostName(), holder().getAddress());
303 }
304
305 /**
306 * Utility routine to check if the InetAddress is an
307 * IP multicast address.
308 * @return a {@code boolean} indicating if the InetAddress is
309 * an IP multicast address
310 * @since 1.1
311 */
312 public boolean isMulticastAddress() {
313 return false;
314 }
315
316 /**
317 * Utility routine to check if the InetAddress in a wildcard address.
318 * @return a {@code boolean} indicating if the Inetaddress is
319 * a wildcard address.
320 * @since 1.4
321 */
322 public boolean isAnyLocalAddress() {
323 return false;
324 }
325
326 /**
327 * Utility routine to check if the InetAddress is a loopback address.
328 *
329 * @return a {@code boolean} indicating if the InetAddress is
330 * a loopback address; or false otherwise.
331 * @since 1.4
332 */
333 public boolean isLoopbackAddress() {
334 return false;
335 }
336
337 /**
338 * Utility routine to check if the InetAddress is an link local address.
339 *
340 * @return a {@code boolean} indicating if the InetAddress is
341 * a link local address; or false if address is not a link local unicast address.
342 * @since 1.4
343 */
344 public boolean isLinkLocalAddress() {
345 return false;
346 }
347
348 /**
349 * Utility routine to check if the InetAddress is a site local address.
350 *
351 * @return a {@code boolean} indicating if the InetAddress is
352 * a site local address; or false if address is not a site local unicast address.
353 * @since 1.4
354 */
355 public boolean isSiteLocalAddress() {
356 return false;
357 }
358
359 /**
360 * Utility routine to check if the multicast address has global scope.
361 *
362 * @return a {@code boolean} indicating if the address has
363 * is a multicast address of global scope, false if it is not
364 * of global scope or it is not a multicast address
365 * @since 1.4
366 */
367 public boolean isMCGlobal() {
368 return false;
369 }
370
371 /**
372 * Utility routine to check if the multicast address has node scope.
373 *
374 * @return a {@code boolean} indicating if the address has
375 * is a multicast address of node-local scope, false if it is not
376 * of node-local scope or it is not a multicast address
377 * @since 1.4
378 */
379 public boolean isMCNodeLocal() {
380 return false;
381 }
382
383 /**
384 * Utility routine to check if the multicast address has link scope.
385 *
386 * @return a {@code boolean} indicating if the address has
387 * is a multicast address of link-local scope, false if it is not
388 * of link-local scope or it is not a multicast address
389 * @since 1.4
390 */
391 public boolean isMCLinkLocal() {
392 return false;
393 }
394
395 /**
396 * Utility routine to check if the multicast address has site scope.
397 *
398 * @return a {@code boolean} indicating if the address has
399 * is a multicast address of site-local scope, false if it is not
400 * of site-local scope or it is not a multicast address
401 * @since 1.4
402 */
403 public boolean isMCSiteLocal() {
404 return false;
405 }
406
407 /**
408 * Utility routine to check if the multicast address has organization scope.
409 *
410 * @return a {@code boolean} indicating if the address has
411 * is a multicast address of organization-local scope,
412 * false if it is not of organization-local scope
413 * or it is not a multicast address
414 * @since 1.4
415 */
416 public boolean isMCOrgLocal() {
417 return false;
418 }
419
420
421 /**
422 * Test whether that address is reachable. Best effort is made by the
423 * implementation to try to reach the host, but firewalls and server
424 * configuration may block requests resulting in a unreachable status
425 * while some specific ports may be accessible.
426 * A typical implementation will use ICMP ECHO REQUESTs if the
427 * privilege can be obtained, otherwise it will try to establish
428 * a TCP connection on port 7 (Echo) of the destination host.
429 * <p>
430 * The timeout value, in milliseconds, indicates the maximum amount of time
431 * the try should take. If the operation times out before getting an
432 * answer, the host is deemed unreachable. A negative value will result
433 * in an IllegalArgumentException being thrown.
434 *
435 * @param timeout the time, in milliseconds, before the call aborts
436 * @return a {@code boolean} indicating if the address is reachable.
437 * @throws IOException if a network error occurs
438 * @throws IllegalArgumentException if {@code timeout} is negative.
439 * @since 1.5
440 */
441 public boolean isReachable(int timeout) throws IOException {
442 return isReachable(null, 0 , timeout);
443 }
444
445 /**
446 * Test whether that address is reachable. Best effort is made by the
447 * implementation to try to reach the host, but firewalls and server
448 * configuration may block requests resulting in a unreachable status
449 * while some specific ports may be accessible.
450 * A typical implementation will use ICMP ECHO REQUESTs if the
451 * privilege can be obtained, otherwise it will try to establish
452 * a TCP connection on port 7 (Echo) of the destination host.
453 * <p>
454 * The {@code network interface} and {@code ttl} parameters
455 * let the caller specify which network interface the test will go through
456 * and the maximum number of hops the packets should go through.
457 * A negative value for the {@code ttl} will result in an
458 * IllegalArgumentException being thrown.
459 * <p>
460 * The timeout value, in milliseconds, indicates the maximum amount of time
461 * the try should take. If the operation times out before getting an
462 * answer, the host is deemed unreachable. A negative value will result
463 * in an IllegalArgumentException being thrown.
464 *
465 * @param netif the NetworkInterface through which the
466 * test will be done, or null for any interface
467 * @param ttl the maximum numbers of hops to try or 0 for the
468 * default
469 * @param timeout the time, in milliseconds, before the call aborts
470 * @throws IllegalArgumentException if either {@code timeout}
471 * or {@code ttl} are negative.
472 * @return a {@code boolean}indicating if the address is reachable.
473 * @throws IOException if a network error occurs
474 * @since 1.5
475 */
476 public boolean isReachable(NetworkInterface netif, int ttl,
477 int timeout) throws IOException {
478 if (ttl < 0)
479 throw new IllegalArgumentException("ttl can't be negative");
480 if (timeout < 0)
481 throw new IllegalArgumentException("timeout can't be negative");
482
483 return impl.isReachable(this, timeout, netif, ttl);
484 }
485
486 /**
487 * Gets the host name for this IP address.
488 *
489 * <p>If this InetAddress was created with a host name,
490 * this host name will be remembered and returned;
491 * otherwise, a reverse name lookup will be performed
492 * and the result will be returned based on the system
493 * configured name lookup service. If a lookup of the name service
494 * is required, call
495 * {@link #getCanonicalHostName() getCanonicalHostName}.
496 *
497 * <p>If there is a security manager, its
498 * {@code checkConnect} method is first called
499 * with the hostname and {@code -1}
500 * as its arguments to see if the operation is allowed.
501 * If the operation is not allowed, it will return
502 * the textual representation of the IP address.
503 *
504 * @return the host name for this IP address, or if the operation
505 * is not allowed by the security check, the textual
506 * representation of the IP address.
507 *
508 * @see InetAddress#getCanonicalHostName
509 * @see SecurityManager#checkConnect
510 */
511 public String getHostName() {
512 return getHostName(true);
513 }
514
515 /**
516 * Returns the hostname for this address.
517 * If the host is equal to null, then this address refers to any
518 * of the local machine's available network addresses.
519 * this is package private so SocketPermission can make calls into
520 * here without a security check.
521 *
522 * <p>If there is a security manager, this method first
523 * calls its {@code checkConnect} method
524 * with the hostname and {@code -1}
525 * as its arguments to see if the calling code is allowed to know
526 * the hostname for this IP address, i.e., to connect to the host.
527 * If the operation is not allowed, it will return
528 * the textual representation of the IP address.
529 *
530 * @return the host name for this IP address, or if the operation
531 * is not allowed by the security check, the textual
532 * representation of the IP address.
533 *
534 * @param check make security check if true
535 *
536 * @see SecurityManager#checkConnect
537 */
538 String getHostName(boolean check) {
539 if (holder().getHostName() == null) {
540 holder().hostName = InetAddress.getHostFromNameService(this, check);
541 }
542 return holder().getHostName();
543 }
544
545 /**
546 * Gets the fully qualified domain name for this IP address.
547 * Best effort method, meaning we may not be able to return
548 * the FQDN depending on the underlying system configuration.
549 *
550 * <p>If there is a security manager, this method first
551 * calls its {@code checkConnect} method
552 * with the hostname and {@code -1}
553 * as its arguments to see if the calling code is allowed to know
554 * the hostname for this IP address, i.e., to connect to the host.
555 * If the operation is not allowed, it will return
556 * the textual representation of the IP address.
557 *
558 * @return the fully qualified domain name for this IP address,
559 * or if the operation is not allowed by the security check,
560 * the textual representation of the IP address.
561 *
562 * @see SecurityManager#checkConnect
563 *
564 * @since 1.4
565 */
566 public String getCanonicalHostName() {
567 if (canonicalHostName == null) {
568 canonicalHostName =
569 InetAddress.getHostFromNameService(this, true);
570 }
571 return canonicalHostName;
572 }
573
574 /**
575 * Returns the hostname for this address.
576 *
577 * <p>If there is a security manager, this method first
578 * calls its {@code checkConnect} method
579 * with the hostname and {@code -1}
580 * as its arguments to see if the calling code is allowed to know
581 * the hostname for this IP address, i.e., to connect to the host.
582 * If the operation is not allowed, it will return
583 * the textual representation of the IP address.
584 *
585 * @return the host name for this IP address, or if the operation
586 * is not allowed by the security check, the textual
587 * representation of the IP address.
588 *
589 * @param check make security check if true
590 *
591 * @see SecurityManager#checkConnect
592 */
593 private static String getHostFromNameService(InetAddress addr, boolean check) {
594 String host = null;
595 for (NameService nameService : nameServices) {
596 try {
597 // first lookup the hostname
598 host = nameService.getHostByAddr(addr.getAddress());
599
600 /* check to see if calling code is allowed to know
601 * the hostname for this IP address, ie, connect to the host
602 */
603 if (check) {
604 SecurityManager sec = System.getSecurityManager();
605 if (sec != null) {
606 sec.checkConnect(host, -1);
607 }
608 }
609
610 /* now get all the IP addresses for this hostname,
611 * and make sure one of them matches the original IP
612 * address. We do this to try and prevent spoofing.
613 */
614
615 InetAddress[] arr = InetAddress.getAllByName0(host, check);
616 boolean ok = false;
617
618 if(arr != null) {
619 for(int i = 0; !ok && i < arr.length; i++) {
620 ok = addr.equals(arr[i]);
621 }
622 }
623
624 //XXX: if it looks a spoof just return the address?
625 if (!ok) {
626 host = addr.getHostAddress();
627 return host;
628 }
629
630 break;
631
632 } catch (SecurityException e) {
633 host = addr.getHostAddress();
634 break;
635 } catch (UnknownHostException e) {
636 host = addr.getHostAddress();
637 // let next provider resolve the hostname
638 }
639 }
640
641 return host;
642 }
643
644 /**
645 * Returns the raw IP address of this {@code InetAddress}
646 * object. The result is in network byte order: the highest order
647 * byte of the address is in {@code getAddress()[0]}.
648 *
649 * @return the raw IP address of this object.
650 */
651 public byte[] getAddress() {
652 return null;
653 }
654
655 /**
656 * Returns the IP address string in textual presentation.
657 *
658 * @return the raw IP address in a string format.
659 * @since 1.0.2
660 */
661 public String getHostAddress() {
662 return null;
663 }
664
665 /**
666 * Returns a hashcode for this IP address.
667 *
668 * @return a hash code value for this IP address.
669 */
670 public int hashCode() {
671 return -1;
672 }
673
674 /**
675 * Compares this object against the specified object.
676 * The result is {@code true} if and only if the argument is
677 * not {@code null} and it represents the same IP address as
678 * this object.
679 * <p>
680 * Two instances of {@code InetAddress} represent the same IP
681 * address if the length of the byte arrays returned by
682 * {@code getAddress} is the same for both, and each of the
683 * array components is the same for the byte arrays.
684 *
685 * @param obj the object to compare against.
686 * @return {@code true} if the objects are the same;
687 * {@code false} otherwise.
688 * @see java.net.InetAddress#getAddress()
689 */
690 public boolean equals(Object obj) {
691 return false;
692 }
693
694 /**
695 * Converts this IP address to a {@code String}. The
696 * string returned is of the form: hostname / literal IP
697 * address.
698 *
699 * If the host name is unresolved, no reverse name service lookup
700 * is performed. The hostname part will be represented by an empty string.
701 *
702 * @return a string representation of this IP address.
703 */
704 public String toString() {
705 String hostName = holder().getHostName();
706 return ((hostName != null) ? hostName : "")
707 + "/" + getHostAddress();
708 }
709
710 // mapping from host name to Addresses - either NameServiceAddresses (while
711 // still being looked-up by NameService(s)) or CachedAddresses when cached
712 private static final ConcurrentMap<String, Addresses> cache =
713 new ConcurrentHashMap<>();
714
715 // CachedAddresses that have to expire are kept ordered in this NavigableSet
716 // which is scanned on each access
717 private static final NavigableSet<CachedAddresses> expirySet =
718 new ConcurrentSkipListSet<>();
719
720 // common interface
721 private interface Addresses {
722 InetAddress[] get() throws UnknownHostException;
723 }
724
725 // a holder for cached addresses with required metadata
726 private static final class CachedAddresses implements Addresses, Comparable<CachedAddresses> {
727 private static final AtomicLong seq = new AtomicLong();
728 final String host;
729 final InetAddress[] inetAddresses;
730 final long expiryTime; // time of expiry (in terms of System.nanoTime())
731 final long id = seq.incrementAndGet(); // each instance is unique
732
733 CachedAddresses(String host, InetAddress[] inetAddresses, long expiryTime) {
734 this.host = host;
735 this.inetAddresses = inetAddresses;
736 this.expiryTime = expiryTime;
737 }
738
739 @Override
740 public InetAddress[] get() throws UnknownHostException {
741 if (inetAddresses == null) {
742 throw new UnknownHostException(host);
743 }
744 return inetAddresses;
745 }
746
747 @Override
748 public int compareTo(CachedAddresses other) {
749 // natural order is expiry time -
750 // compare difference of expiry times rather than
751 // expiry times directly, to avoid possible overflow.
752 // (see System.nanoTime() recommendations...)
753 long diff = this.expiryTime - other.expiryTime;
754 if (diff < 0L) return -1;
755 if (diff > 0L) return 1;
756 // ties are broken using unique id
757 return Long.compare(this.id, other.id);
758 }
759 }
760
761 // a name service lookup based Addresses implementation which replaces itself
762 // in cache when the result is obtained
763 private static final class NameServiceAddresses implements Addresses {
764 private final String host;
765 private final InetAddress reqAddr;
766
767 NameServiceAddresses(String host, InetAddress reqAddr) {
768 this.host = host;
769 this.reqAddr = reqAddr;
770 }
771
772 @Override
773 public InetAddress[] get() throws UnknownHostException {
774 Addresses addresses;
775 // only one thread is doing lookup to name service
776 // for particular host at any time.
777 synchronized (this) {
778 // re-check that we are still us + re-install us if slot empty
779 addresses = cache.putIfAbsent(host, this);
780 if (addresses == null) {
781 // this can happen when we were replaced by CachedAddresses in
782 // some other thread, then CachedAddresses expired and were
783 // removed from cache while we were waiting for lock...
784 addresses = this;
785 }
786 // still us ?
787 if (addresses == this) {
788 // lookup name services
789 InetAddress[] inetAddresses;
790 UnknownHostException ex;
791 int cachePolicy;
792 try {
793 inetAddresses = getAddressesFromNameService(host, reqAddr);
794 ex = null;
795 cachePolicy = InetAddressCachePolicy.get();
796 } catch (UnknownHostException uhe) {
797 inetAddresses = null;
798 ex = uhe;
799 cachePolicy = InetAddressCachePolicy.getNegative();
800 }
801 // remove or replace us with cached addresses according to cachePolicy
802 if (cachePolicy == InetAddressCachePolicy.NEVER) {
803 cache.remove(host, this);
804 } else {
805 CachedAddresses cachedAddresses = new CachedAddresses(
806 host,
807 inetAddresses,
808 cachePolicy == InetAddressCachePolicy.FOREVER
809 ? 0L
810 // cachePolicy is in [s] - we need [ns]
811 : System.nanoTime() + 1000_000_000L * cachePolicy
812 );
813 if (cache.replace(host, this, cachedAddresses) &&
814 cachePolicy != InetAddressCachePolicy.FOREVER) {
815 // schedule expiry
816 expirySet.add(cachedAddresses);
817 }
818 }
819 if (inetAddresses == null) {
820 throw ex == null ? new UnknownHostException(host) : ex;
821 }
822 return inetAddresses;
823 }
824 // else addresses != this
825 }
826 // delegate to different addresses when we are already replaced
827 // but outside of synchronized block to avoid any chance of dead-locking
828 return addresses.get();
829 }
830 }
831
832 static InetAddressImpl impl;
833
834 private static NameService createNSProvider(String provider) {
835 if (provider == null)
836 return null;
837
838 NameService nameService = null;
839 if (provider.equals("default")) {
840 // initialize the default name service
841 nameService = new NameService() {
842 public InetAddress[] lookupAllHostAddr(String host)
843 throws UnknownHostException {
844 return impl.lookupAllHostAddr(host);
845 }
846 public String getHostByAddr(byte[] addr)
847 throws UnknownHostException {
848 return impl.getHostByAddr(addr);
849 }
850 };
851 } else {
852 final String providerName = provider;
853 try {
854 nameService = java.security.AccessController.doPrivileged(
855 new java.security.PrivilegedExceptionAction<>() {
856 public NameService run() {
857 Iterator<NameServiceDescriptor> itr =
858 ServiceLoader.load(NameServiceDescriptor.class)
859 .iterator();
860 while (itr.hasNext()) {
861 NameServiceDescriptor nsd = itr.next();
862 if (providerName.
863 equalsIgnoreCase(nsd.getType()+","
864 +nsd.getProviderName())) {
865 try {
866 return nsd.createNameService();
867 } catch (Exception e) {
868 e.printStackTrace();
869 System.err.println(
870 "Cannot create name service:"
871 +providerName+": " + e);
872 }
873 }
874 }
875
876 return null;
877 }
878 }
879 );
880 } catch (java.security.PrivilegedActionException e) {
881 }
882 }
883
884 return nameService;
885 }
886
887 static {
888 // create the impl
889 impl = InetAddressImplFactory.create();
890
891 // get name service if provided and requested
892 String provider = null;;
893 String propPrefix = "sun.net.spi.nameservice.provider.";
894 int n = 1;
895 nameServices = new ArrayList<>();
896 provider = AccessController.doPrivileged(
897 new GetPropertyAction(propPrefix + n));
898 while (provider != null) {
899 NameService ns = createNSProvider(provider);
900 if (ns != null)
901 nameServices.add(ns);
902
903 n++;
904 provider = AccessController.doPrivileged(
905 new GetPropertyAction(propPrefix + n));
906 }
907
908 // if not designate any name services provider,
909 // create a default one
910 if (nameServices.size() == 0) {
911 NameService ns = createNSProvider("default");
912 nameServices.add(ns);
913 }
914 }
915
916 /**
917 * Creates an InetAddress based on the provided host name and IP address.
918 * No name service is checked for the validity of the address.
919 *
920 * <p> The host name can either be a machine name, such as
921 * "{@code java.sun.com}", or a textual representation of its IP
922 * address.
923 * <p> No validity checking is done on the host name either.
924 *
925 * <p> If addr specifies an IPv4 address an instance of Inet4Address
926 * will be returned; otherwise, an instance of Inet6Address
927 * will be returned.
928 *
929 * <p> IPv4 address byte array must be 4 bytes long and IPv6 byte array
930 * must be 16 bytes long
931 *
932 * @param host the specified host
933 * @param addr the raw IP address in network byte order
934 * @return an InetAddress object created from the raw IP address.
935 * @exception UnknownHostException if IP address is of illegal length
936 * @since 1.4
937 */
938 public static InetAddress getByAddress(String host, byte[] addr)
939 throws UnknownHostException {
940 if (host != null && host.length() > 0 && host.charAt(0) == '[') {
941 if (host.charAt(host.length()-1) == ']') {
942 host = host.substring(1, host.length() -1);
943 }
944 }
945 if (addr != null) {
946 if (addr.length == Inet4Address.INADDRSZ) {
947 return new Inet4Address(host, addr);
948 } else if (addr.length == Inet6Address.INADDRSZ) {
949 byte[] newAddr
950 = IPAddressUtil.convertFromIPv4MappedAddress(addr);
951 if (newAddr != null) {
952 return new Inet4Address(host, newAddr);
953 } else {
954 return new Inet6Address(host, addr);
955 }
956 }
957 }
958 throw new UnknownHostException("addr is of illegal length");
959 }
960
961
962 /**
963 * Determines the IP address of a host, given the host's name.
964 *
965 * <p> The host name can either be a machine name, such as
966 * "{@code java.sun.com}", or a textual representation of its
967 * IP address. If a literal IP address is supplied, only the
968 * validity of the address format is checked.
969 *
970 * <p> For {@code host} specified in literal IPv6 address,
971 * either the form defined in RFC 2732 or the literal IPv6 address
972 * format defined in RFC 2373 is accepted. IPv6 scoped addresses are also
973 * supported. See <a href="Inet6Address.html#scoped">here</a> for a description of IPv6
974 * scoped addresses.
975 *
976 * <p> If the host is {@code null} then an {@code InetAddress}
977 * representing an address of the loopback interface is returned.
978 * See <a href="http://www.ietf.org/rfc/rfc3330.txt">RFC 3330</a>
979 * section 2 and <a href="http://www.ietf.org/rfc/rfc2373.txt">RFC 2373</a>
980 * section 2.5.3. </p>
981 *
982 * @param host the specified host, or {@code null}.
983 * @return an IP address for the given host name.
984 * @exception UnknownHostException if no IP address for the
985 * {@code host} could be found, or if a scope_id was specified
986 * for a global IPv6 address.
987 * @exception SecurityException if a security manager exists
988 * and its checkConnect method doesn't allow the operation
989 */
990 public static InetAddress getByName(String host)
991 throws UnknownHostException {
992 return InetAddress.getAllByName(host)[0];
993 }
994
995 // called from deployment cache manager
996 private static InetAddress getByName(String host, InetAddress reqAddr)
997 throws UnknownHostException {
998 return InetAddress.getAllByName(host, reqAddr)[0];
999 }
1000
1001 /**
1002 * Given the name of a host, returns an array of its IP addresses,
1003 * based on the configured name service on the system.
1004 *
1005 * <p> The host name can either be a machine name, such as
1006 * "{@code java.sun.com}", or a textual representation of its IP
1007 * address. If a literal IP address is supplied, only the
1008 * validity of the address format is checked.
1009 *
1010 * <p> For {@code host} specified in <i>literal IPv6 address</i>,
1011 * either the form defined in RFC 2732 or the literal IPv6 address
1012 * format defined in RFC 2373 is accepted. A literal IPv6 address may
1013 * also be qualified by appending a scoped zone identifier or scope_id.
1014 * The syntax and usage of scope_ids is described
1015 * <a href="Inet6Address.html#scoped">here</a>.
1016 * <p> If the host is {@code null} then an {@code InetAddress}
1017 * representing an address of the loopback interface is returned.
1018 * See <a href="http://www.ietf.org/rfc/rfc3330.txt">RFC 3330</a>
1019 * section 2 and <a href="http://www.ietf.org/rfc/rfc2373.txt">RFC 2373</a>
1020 * section 2.5.3. </p>
1021 *
1022 * <p> If there is a security manager and {@code host} is not
1023 * null and {@code host.length() } is not equal to zero, the
1024 * security manager's
1025 * {@code checkConnect} method is called
1026 * with the hostname and {@code -1}
1027 * as its arguments to see if the operation is allowed.
1028 *
1029 * @param host the name of the host, or {@code null}.
1030 * @return an array of all the IP addresses for a given host name.
1031 *
1032 * @exception UnknownHostException if no IP address for the
1033 * {@code host} could be found, or if a scope_id was specified
1034 * for a global IPv6 address.
1035 * @exception SecurityException if a security manager exists and its
1036 * {@code checkConnect} method doesn't allow the operation.
1037 *
1038 * @see SecurityManager#checkConnect
1039 */
1040 public static InetAddress[] getAllByName(String host)
1041 throws UnknownHostException {
1042 return getAllByName(host, null);
1043 }
1044
1045 private static InetAddress[] getAllByName(String host, InetAddress reqAddr)
1046 throws UnknownHostException {
1047
1048 if (host == null || host.length() == 0) {
1049 InetAddress[] ret = new InetAddress[1];
1050 ret[0] = impl.loopbackAddress();
1051 return ret;
1052 }
1053
1054 boolean ipv6Expected = false;
1055 if (host.charAt(0) == '[') {
1056 // This is supposed to be an IPv6 literal
1057 if (host.length() > 2 && host.charAt(host.length()-1) == ']') {
1058 host = host.substring(1, host.length() -1);
1059 ipv6Expected = true;
1060 } else {
1061 // This was supposed to be a IPv6 address, but it's not!
1062 throw new UnknownHostException(host + ": invalid IPv6 address");
1063 }
1064 }
1065
1066 // if host is an IP address, we won't do further lookup
1067 if (Character.digit(host.charAt(0), 16) != -1
1068 || (host.charAt(0) == ':')) {
1069 byte[] addr = null;
1070 int numericZone = -1;
1071 String ifname = null;
1072 // see if it is IPv4 address
1073 addr = IPAddressUtil.textToNumericFormatV4(host);
1074 if (addr == null) {
1075 // This is supposed to be an IPv6 literal
1076 // Check if a numeric or string zone id is present
1077 int pos;
1078 if ((pos=host.indexOf ('%')) != -1) {
1079 numericZone = checkNumericZone (host);
1080 if (numericZone == -1) { /* remainder of string must be an ifname */
1081 ifname = host.substring (pos+1);
1082 }
1083 }
1084 if ((addr = IPAddressUtil.textToNumericFormatV6(host)) == null && host.contains(":")) {
1085 throw new UnknownHostException(host + ": invalid IPv6 address");
1086 }
1087 } else if (ipv6Expected) {
1088 // Means an IPv4 litteral between brackets!
1089 throw new UnknownHostException("["+host+"]");
1090 }
1091 InetAddress[] ret = new InetAddress[1];
1092 if(addr != null) {
1093 if (addr.length == Inet4Address.INADDRSZ) {
1094 ret[0] = new Inet4Address(null, addr);
1095 } else {
1096 if (ifname != null) {
1097 ret[0] = new Inet6Address(null, addr, ifname);
1098 } else {
1099 ret[0] = new Inet6Address(null, addr, numericZone);
1100 }
1101 }
1102 return ret;
1103 }
1104 } else if (ipv6Expected) {
1105 // We were expecting an IPv6 Litteral, but got something else
1106 throw new UnknownHostException("["+host+"]");
1107 }
1108 return getAllByName0(host, reqAddr, true, true);
1109 }
1110
1111 /**
1112 * Returns the loopback address.
1113 * <p>
1114 * The InetAddress returned will represent the IPv4
1115 * loopback address, 127.0.0.1, or the IPv6 loopback
1116 * address, ::1. The IPv4 loopback address returned
1117 * is only one of many in the form 127.*.*.*
1118 *
1119 * @return the InetAddress loopback instance.
1120 * @since 1.7
1121 */
1122 public static InetAddress getLoopbackAddress() {
1123 return impl.loopbackAddress();
1124 }
1125
1126
1127 /**
1128 * check if the literal address string has %nn appended
1129 * returns -1 if not, or the numeric value otherwise.
1130 *
1131 * %nn may also be a string that represents the displayName of
1132 * a currently available NetworkInterface.
1133 */
1134 private static int checkNumericZone (String s) throws UnknownHostException {
1135 int percent = s.indexOf ('%');
1136 int slen = s.length();
1137 int digit, zone=0;
1138 if (percent == -1) {
1139 return -1;
1140 }
1141 for (int i=percent+1; i<slen; i++) {
1142 char c = s.charAt(i);
1143 if (c == ']') {
1144 if (i == percent+1) {
1145 /* empty per-cent field */
1146 return -1;
1147 }
1148 break;
1149 }
1150 if ((digit = Character.digit (c, 10)) < 0) {
1151 return -1;
1152 }
1153 zone = (zone * 10) + digit;
1154 }
1155 return zone;
1156 }
1157
1158 private static InetAddress[] getAllByName0 (String host)
1159 throws UnknownHostException
1160 {
1161 return getAllByName0(host, true);
1162 }
1163
1164 /**
1165 * package private so SocketPermission can call it
1166 */
1167 static InetAddress[] getAllByName0 (String host, boolean check)
1168 throws UnknownHostException {
1169 return getAllByName0 (host, null, check, true);
1170 }
1171
1172 /**
1173 * Designated lookup method.
1174 *
1175 * @param host host name to look up
1176 * @param reqAddr requested address to be the 1st in returned array
1177 * @param check perform security check
1178 * @param useCache use cached value if not expired else always
1179 * perform name service lookup (and cache the result)
1180 * @return array of InetAddress(es)
1181 * @throws UnknownHostException if host name is not found
1182 */
1183 private static InetAddress[] getAllByName0(String host,
1184 InetAddress reqAddr,
1185 boolean check,
1186 boolean useCache)
1187 throws UnknownHostException {
1188
1189 /* If it gets here it is presumed to be a hostname */
1190
1191 /* make sure the connection to the host is allowed, before we
1192 * give out a hostname
1193 */
1194 if (check) {
1195 SecurityManager security = System.getSecurityManager();
1196 if (security != null) {
1197 security.checkConnect(host, -1);
1198 }
1199 }
1200
1201 // remove expired addresses from cache - expirySet keeps them ordered
1202 // by expiry time so we only need to iterate the prefix of the NavigableSet...
1203 long now = System.nanoTime();
1204 for (CachedAddresses caddrs : expirySet) {
1205 // compare difference of time instants rather than
1206 // time instants directly, to avoid possible overflow.
1207 // (see System.nanoTime() recommendations...)
1208 if ((caddrs.expiryTime - now) < 0L) {
1209 // ConcurrentSkipListSet uses weakly consistent iterator,
1210 // so removing while iterating is OK...
1211 if (expirySet.remove(caddrs)) {
1212 // ... remove from cache
1213 cache.remove(caddrs.host, caddrs);
1214 }
1215 } else {
1216 // we encountered 1st element that expires in future
1217 break;
1218 }
1219 }
1220
1221 // look-up or remove from cache
1222 Addresses addrs;
1223 if (useCache) {
1224 addrs = cache.get(host);
1225 } else {
1226 addrs = cache.remove(host);
1227 if (addrs != null) {
1228 if (addrs instanceof CachedAddresses) {
1229 // try removing from expirySet too if CachedAddresses
1230 expirySet.remove(addrs);
1231 }
1232 addrs = null;
1233 }
1234 }
1235
1236 if (addrs == null) {
1237 // create a NameServiceAddresses instance which will look up
1238 // the name service and install it within cache...
1239 Addresses oldAddrs = cache.putIfAbsent(
1240 host,
1241 addrs = new NameServiceAddresses(host, reqAddr)
1242 );
1243 if (oldAddrs != null) { // lost putIfAbsent race
1244 addrs = oldAddrs;
1245 }
1246 }
1247
1248 // ask Addresses to get an array of InetAddress(es) and clone it
1249 return addrs.get().clone();
1250 }
1251
1252 static InetAddress[] getAddressesFromNameService(String host, InetAddress reqAddr)
1253 throws UnknownHostException
1254 {
1255 InetAddress[] addresses = null;
1256 UnknownHostException ex = null;
1257
1258 for (NameService nameService : nameServices) {
1259 try {
1260 addresses = nameService.lookupAllHostAddr(host);
1261 break;
1262 } catch (UnknownHostException uhe) {
1263 if (host.equalsIgnoreCase("localhost")) {
1264 addresses = new InetAddress[] { impl.loopbackAddress() };
1265 break;
1266 }
1267 else {
1268 ex = uhe;
1269 }
1270 }
1271 }
1272
1273 if (addresses == null) {
1274 throw ex == null ? new UnknownHostException(host) : ex;
1275 }
1276
1277 // More to do?
1278 if (reqAddr != null && addresses.length > 1 && !addresses[0].equals(reqAddr)) {
1279 // Find it?
1280 int i = 1;
1281 for (; i < addresses.length; i++) {
1282 if (addresses[i].equals(reqAddr)) {
1283 break;
1284 }
1285 }
1286 // Rotate
1287 if (i < addresses.length) {
1288 InetAddress tmp, tmp2 = reqAddr;
1289 for (int j = 0; j < i; j++) {
1290 tmp = addresses[j];
1291 addresses[j] = tmp2;
1292 tmp2 = tmp;
1293 }
1294 addresses[i] = tmp2;
1295 }
1296 }
1297
1298 return addresses;
1299 }
1300
1301 /**
1302 * Returns an {@code InetAddress} object given the raw IP address .
1303 * The argument is in network byte order: the highest order
1304 * byte of the address is in {@code getAddress()[0]}.
1305 *
1306 * <p> This method doesn't block, i.e. no reverse name service lookup
1307 * is performed.
1308 *
1309 * <p> IPv4 address byte array must be 4 bytes long and IPv6 byte array
1310 * must be 16 bytes long
1311 *
1312 * @param addr the raw IP address in network byte order
1313 * @return an InetAddress object created from the raw IP address.
1314 * @exception UnknownHostException if IP address is of illegal length
1315 * @since 1.4
1316 */
1317 public static InetAddress getByAddress(byte[] addr)
1318 throws UnknownHostException {
1319 return getByAddress(null, addr);
1320 }
1321
1322 private static final class CachedLocalHost {
1323 final String host;
1324 final InetAddress addr;
1325 final long expiryTime = System.nanoTime() + 5000_000_000L; // now + 5s;
1326
1327 CachedLocalHost(String host, InetAddress addr) {
1328 this.host = host;
1329 this.addr = addr;
1330 }
1331 }
1332
1333 private static volatile CachedLocalHost cachedLocalHost;
1334
1335 /**
1336 * Returns the address of the local host. This is achieved by retrieving
1337 * the name of the host from the system, then resolving that name into
1338 * an {@code InetAddress}.
1339 *
1340 * <P>Note: The resolved address may be cached for a short period of time.
1341 * </P>
1342 *
1343 * <p>If there is a security manager, its
1344 * {@code checkConnect} method is called
1345 * with the local host name and {@code -1}
1346 * as its arguments to see if the operation is allowed.
1347 * If the operation is not allowed, an InetAddress representing
1348 * the loopback address is returned.
1349 *
1350 * @return the address of the local host.
1351 *
1352 * @exception UnknownHostException if the local host name could not
1353 * be resolved into an address.
1354 *
1355 * @see SecurityManager#checkConnect
1356 * @see java.net.InetAddress#getByName(java.lang.String)
1357 */
1358 public static InetAddress getLocalHost() throws UnknownHostException {
1359
1360 SecurityManager security = System.getSecurityManager();
1361 try {
1362 // is cached data still valid?
1363 CachedLocalHost clh = cachedLocalHost;
1364 if (clh != null && (clh.expiryTime - System.nanoTime()) >= 0L) {
1365 if (security != null) {
1366 security.checkConnect(clh.host, -1);
1367 }
1368 return clh.addr;
1369 }
1370
1371 String local = impl.getLocalHostName();
1372
1373 if (security != null) {
1374 security.checkConnect(local, -1);
1375 }
1376
1377 InetAddress localAddr;
1378 if (local.equals("localhost")) {
1379 // shortcut for "localhost" host name
1380 localAddr = impl.loopbackAddress();
1381 } else {
1382 // call getAllByName0 without security checks and
1383 // without using cached data
1384 try {
1385 localAddr = getAllByName0(local, null, false, false)[0];
1386 } catch (UnknownHostException uhe) {
1387 // Rethrow with a more informative error message.
1388 UnknownHostException uhe2 =
1389 new UnknownHostException(local + ": " +
1390 uhe.getMessage());
1391 uhe2.initCause(uhe);
1392 throw uhe2;
1393 }
1394 }
1395 cachedLocalHost = new CachedLocalHost(local, localAddr);
1396 return localAddr;
1397 } catch (java.lang.SecurityException e) {
1398 return impl.loopbackAddress();
1399 }
1400 }
1401
1402 /**
1403 * Perform class load-time initializations.
1404 */
1405 private static native void init();
1406
1407
1408 /*
1409 * Returns the InetAddress representing anyLocalAddress
1410 * (typically 0.0.0.0 or ::0)
1411 */
1412 static InetAddress anyLocalAddress() {
1413 return impl.anyLocalAddress();
1414 }
1415
1416 /*
1417 * Load and instantiate an underlying impl class
1418 */
1419 static InetAddressImpl loadImpl(String implName) {
1420 Object impl = null;
1421
1422 /*
1423 * Property "impl.prefix" will be prepended to the classname
1424 * of the implementation object we instantiate, to which we
1425 * delegate the real work (like native methods). This
1426 * property can vary across implementations of the java.
1427 * classes. The default is an empty String "".
1428 */
1429 String prefix = AccessController.doPrivileged(
1430 new GetPropertyAction("impl.prefix", ""));
1431 try {
1432 impl = Class.forName("java.net." + prefix + implName).newInstance();
1433 } catch (ClassNotFoundException e) {
1434 System.err.println("Class not found: java.net." + prefix +
1435 implName + ":\ncheck impl.prefix property " +
1436 "in your properties file.");
1437 } catch (InstantiationException e) {
1438 System.err.println("Could not instantiate: java.net." + prefix +
1439 implName + ":\ncheck impl.prefix property " +
1440 "in your properties file.");
1441 } catch (IllegalAccessException e) {
1442 System.err.println("Cannot access class: java.net." + prefix +
1443 implName + ":\ncheck impl.prefix property " +
1444 "in your properties file.");
1445 }
1446
1447 if (impl == null) {
1448 try {
1449 impl = Class.forName(implName).newInstance();
1450 } catch (Exception e) {
1451 throw new Error("System property impl.prefix incorrect");
1452 }
1453 }
1454
1455 return (InetAddressImpl) impl;
1456 }
1457
1458 private void readObjectNoData (ObjectInputStream s) throws
1459 IOException, ClassNotFoundException {
1460 if (getClass().getClassLoader() != null) {
1461 throw new SecurityException ("invalid address type");
1462 }
1463 }
1464
1465 private static final long FIELDS_OFFSET;
1466 private static final sun.misc.Unsafe UNSAFE;
1467
1468 static {
1469 try {
1470 sun.misc.Unsafe unsafe = sun.misc.Unsafe.getUnsafe();
1471 FIELDS_OFFSET = unsafe.objectFieldOffset(
1472 InetAddress.class.getDeclaredField("holder")
1473 );
1474 UNSAFE = unsafe;
1475 } catch (ReflectiveOperationException e) {
1476 throw new Error(e);
1477 }
1478 }
1479
1480 private void readObject (ObjectInputStream s) throws
1481 IOException, ClassNotFoundException {
1482 if (getClass().getClassLoader() != null) {
1483 throw new SecurityException ("invalid address type");
1484 }
1485 GetField gf = s.readFields();
1486 String host = (String)gf.get("hostName", null);
1487 int address= gf.get("address", 0);
1488 int family= gf.get("family", 0);
1489 InetAddressHolder h = new InetAddressHolder(host, address, family);
1490 UNSAFE.putObject(this, FIELDS_OFFSET, h);
1491 }
1492
1493 /* needed because the serializable fields no longer exist */
1494
1495 /**
1496 * @serialField hostName String
1497 * @serialField address int
1498 * @serialField family int
1499 */
1500 private static final ObjectStreamField[] serialPersistentFields = {
1501 new ObjectStreamField("hostName", String.class),
1502 new ObjectStreamField("address", int.class),
1503 new ObjectStreamField("family", int.class),
1504 };
1505
1506 private void writeObject (ObjectOutputStream s) throws
1507 IOException {
1508 if (getClass().getClassLoader() != null) {
1509 throw new SecurityException ("invalid address type");
1510 }
1511 PutField pf = s.putFields();
1512 pf.put("hostName", holder().getHostName());
1513 pf.put("address", holder().getAddress());
1514 pf.put("family", holder().getFamily());
1515 s.writeFields();
1516 }
1517 }
1518
1519 /*
1520 * Simple factory to create the impl
1521 */
1522 class InetAddressImplFactory {
1523
1524 static InetAddressImpl create() {
1525 return InetAddress.loadImpl(isIPv6Supported() ?
1526 "Inet6AddressImpl" : "Inet4AddressImpl");
1527 }
1528
1529 static native boolean isIPv6Supported();
1530 }