2
|
1 |
/*
|
|
2 |
* Copyright 1995-2007 Sun Microsystems, Inc. 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. Sun designates this
|
|
8 |
* particular file as subject to the "Classpath" exception as provided
|
|
9 |
* by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
|
|
22 |
* CA 95054 USA or visit www.sun.com if you need additional information or
|
|
23 |
* have any questions.
|
|
24 |
*/
|
|
25 |
|
|
26 |
package java.net;
|
|
27 |
|
|
28 |
import java.util.HashMap;
|
|
29 |
import java.util.LinkedHashMap;
|
|
30 |
import java.util.Random;
|
|
31 |
import java.util.Iterator;
|
|
32 |
import java.util.LinkedList;
|
|
33 |
import java.util.List;
|
|
34 |
import java.util.ArrayList;
|
|
35 |
import java.security.AccessController;
|
|
36 |
import java.io.ObjectStreamException;
|
|
37 |
import java.io.IOException;
|
|
38 |
import sun.security.action.*;
|
|
39 |
import sun.net.InetAddressCachePolicy;
|
|
40 |
import sun.net.util.IPAddressUtil;
|
|
41 |
import sun.misc.Service;
|
|
42 |
import sun.net.spi.nameservice.*;
|
|
43 |
|
|
44 |
/**
|
|
45 |
* This class represents an Internet Protocol (IP) address.
|
|
46 |
*
|
|
47 |
* <p> An IP address is either a 32-bit or 128-bit unsigned number
|
|
48 |
* used by IP, a lower-level protocol on which protocols like UDP and
|
|
49 |
* TCP are built. The IP address architecture is defined by <a
|
|
50 |
* href="http://www.ietf.org/rfc/rfc790.txt"><i>RFC 790:
|
|
51 |
* Assigned Numbers</i></a>, <a
|
|
52 |
* href="http://www.ietf.org/rfc/rfc1918.txt"> <i>RFC 1918:
|
|
53 |
* Address Allocation for Private Internets</i></a>, <a
|
|
54 |
* href="http://www.ietf.org/rfc/rfc2365.txt"><i>RFC 2365:
|
|
55 |
* Administratively Scoped IP Multicast</i></a>, and <a
|
|
56 |
* href="http://www.ietf.org/rfc/rfc2373.txt"><i>RFC 2373: IP
|
|
57 |
* Version 6 Addressing Architecture</i></a>. An instance of an
|
|
58 |
* InetAddress consists of an IP address and possibly its
|
|
59 |
* corresponding host name (depending on whether it is constructed
|
|
60 |
* with a host name or whether it has already done reverse host name
|
|
61 |
* resolution).
|
|
62 |
*
|
|
63 |
* <h4> Address types </h4>
|
|
64 |
*
|
|
65 |
* <blockquote><table cellspacing=2 summary="Description of unicast and multicast address types">
|
|
66 |
* <tr><th valign=top><i>unicast</i></th>
|
|
67 |
* <td>An identifier for a single interface. A packet sent to
|
|
68 |
* a unicast address is delivered to the interface identified by
|
|
69 |
* that address.
|
|
70 |
*
|
|
71 |
* <p> The Unspecified Address -- Also called anylocal or wildcard
|
|
72 |
* address. It must never be assigned to any node. It indicates the
|
|
73 |
* absence of an address. One example of its use is as the target of
|
|
74 |
* bind, which allows a server to accept a client connection on any
|
|
75 |
* interface, in case the server host has multiple interfaces.
|
|
76 |
*
|
|
77 |
* <p> The <i>unspecified</i> address must not be used as
|
|
78 |
* the destination address of an IP packet.
|
|
79 |
*
|
|
80 |
* <p> The <i>Loopback</i> Addresses -- This is the address
|
|
81 |
* assigned to the loopback interface. Anything sent to this
|
|
82 |
* IP address loops around and becomes IP input on the local
|
|
83 |
* host. This address is often used when testing a
|
|
84 |
* client.</td></tr>
|
|
85 |
* <tr><th valign=top><i>multicast</i></th>
|
|
86 |
* <td>An identifier for a set of interfaces (typically belonging
|
|
87 |
* to different nodes). A packet sent to a multicast address is
|
|
88 |
* delivered to all interfaces identified by that address.</td></tr>
|
|
89 |
* </table></blockquote>
|
|
90 |
*
|
|
91 |
* <h4> IP address scope </h4>
|
|
92 |
*
|
|
93 |
* <p> <i>Link-local</i> addresses are designed to be used for addressing
|
|
94 |
* on a single link for purposes such as auto-address configuration,
|
|
95 |
* neighbor discovery, or when no routers are present.
|
|
96 |
*
|
|
97 |
* <p> <i>Site-local</i> addresses are designed to be used for addressing
|
|
98 |
* inside of a site without the need for a global prefix.
|
|
99 |
*
|
|
100 |
* <p> <i>Global</i> addresses are unique across the internet.
|
|
101 |
*
|
|
102 |
* <h4> Textual representation of IP addresses </h4>
|
|
103 |
*
|
|
104 |
* The textual representation of an IP address is address family specific.
|
|
105 |
*
|
|
106 |
* <p>
|
|
107 |
*
|
|
108 |
* For IPv4 address format, please refer to <A
|
|
109 |
* HREF="Inet4Address.html#format">Inet4Address#format</A>; For IPv6
|
|
110 |
* address format, please refer to <A
|
|
111 |
* HREF="Inet6Address.html#format">Inet6Address#format</A>.
|
|
112 |
*
|
|
113 |
* <P>There is a <a href="doc-files/net-properties.html#Ipv4IPv6">couple of
|
|
114 |
* System Properties</a> affecting how IPv4 and IPv6 addresses are used.</P>
|
|
115 |
*
|
|
116 |
* <h4> Host Name Resolution </h4>
|
|
117 |
*
|
|
118 |
* Host name-to-IP address <i>resolution</i> is accomplished through
|
|
119 |
* the use of a combination of local machine configuration information
|
|
120 |
* and network naming services such as the Domain Name System (DNS)
|
|
121 |
* and Network Information Service(NIS). The particular naming
|
|
122 |
* services(s) being used is by default the local machine configured
|
|
123 |
* one. For any host name, its corresponding IP address is returned.
|
|
124 |
*
|
|
125 |
* <p> <i>Reverse name resolution</i> means that for any IP address,
|
|
126 |
* the host associated with the IP address is returned.
|
|
127 |
*
|
|
128 |
* <p> The InetAddress class provides methods to resolve host names to
|
|
129 |
* their IP addresses and vice versa.
|
|
130 |
*
|
|
131 |
* <h4> InetAddress Caching </h4>
|
|
132 |
*
|
|
133 |
* The InetAddress class has a cache to store successful as well as
|
|
134 |
* unsuccessful host name resolutions.
|
|
135 |
*
|
|
136 |
* <p> By default, when a security manager is installed, in order to
|
|
137 |
* protect against DNS spoofing attacks,
|
|
138 |
* the result of positive host name resolutions are
|
|
139 |
* cached forever. When a security manager is not installed, the default
|
|
140 |
* behavior is to cache entries for a finite (implementation dependent)
|
|
141 |
* period of time. The result of unsuccessful host
|
|
142 |
* name resolution is cached for a very short period of time (10
|
|
143 |
* seconds) to improve performance.
|
|
144 |
*
|
|
145 |
* <p> If the default behavior is not desired, then a Java security property
|
|
146 |
* can be set to a different Time-to-live (TTL) value for positive
|
|
147 |
* caching. Likewise, a system admin can configure a different
|
|
148 |
* negative caching TTL value when needed.
|
|
149 |
*
|
|
150 |
* <p> Two Java security properties control the TTL values used for
|
|
151 |
* positive and negative host name resolution caching:
|
|
152 |
*
|
|
153 |
* <blockquote>
|
|
154 |
* <dl>
|
|
155 |
* <dt><b>networkaddress.cache.ttl</b></dt>
|
|
156 |
* <dd>Indicates the caching policy for successful name lookups from
|
|
157 |
* the name service. The value is specified as as integer to indicate
|
|
158 |
* the number of seconds to cache the successful lookup. The default
|
|
159 |
* setting is to cache for an implementation specific period of time.
|
|
160 |
* <p>
|
|
161 |
* A value of -1 indicates "cache forever".
|
|
162 |
* </dd>
|
|
163 |
* <p>
|
|
164 |
* <dt><b>networkaddress.cache.negative.ttl</b> (default: 10)</dt>
|
|
165 |
* <dd>Indicates the caching policy for un-successful name lookups
|
|
166 |
* from the name service. The value is specified as as integer to
|
|
167 |
* indicate the number of seconds to cache the failure for
|
|
168 |
* un-successful lookups.
|
|
169 |
* <p>
|
|
170 |
* A value of 0 indicates "never cache".
|
|
171 |
* A value of -1 indicates "cache forever".
|
|
172 |
* </dd>
|
|
173 |
* </dl>
|
|
174 |
* </blockquote>
|
|
175 |
*
|
|
176 |
* @author Chris Warth
|
|
177 |
* @see java.net.InetAddress#getByAddress(byte[])
|
|
178 |
* @see java.net.InetAddress#getByAddress(java.lang.String, byte[])
|
|
179 |
* @see java.net.InetAddress#getAllByName(java.lang.String)
|
|
180 |
* @see java.net.InetAddress#getByName(java.lang.String)
|
|
181 |
* @see java.net.InetAddress#getLocalHost()
|
|
182 |
* @since JDK1.0
|
|
183 |
*/
|
|
184 |
public
|
|
185 |
class InetAddress implements java.io.Serializable {
|
|
186 |
/**
|
|
187 |
* Specify the address family: Internet Protocol, Version 4
|
|
188 |
* @since 1.4
|
|
189 |
*/
|
|
190 |
static final int IPv4 = 1;
|
|
191 |
|
|
192 |
/**
|
|
193 |
* Specify the address family: Internet Protocol, Version 6
|
|
194 |
* @since 1.4
|
|
195 |
*/
|
|
196 |
static final int IPv6 = 2;
|
|
197 |
|
|
198 |
/* Specify address family preference */
|
|
199 |
static transient boolean preferIPv6Address = false;
|
|
200 |
|
|
201 |
/**
|
|
202 |
* @serial
|
|
203 |
*/
|
|
204 |
String hostName;
|
|
205 |
|
|
206 |
/**
|
|
207 |
* Holds a 32-bit IPv4 address.
|
|
208 |
*
|
|
209 |
* @serial
|
|
210 |
*/
|
|
211 |
int address;
|
|
212 |
|
|
213 |
/**
|
|
214 |
* Specifies the address family type, for instance, '1' for IPv4
|
|
215 |
* addresses, and '2' for IPv6 addresses.
|
|
216 |
*
|
|
217 |
* @serial
|
|
218 |
*/
|
|
219 |
int family;
|
|
220 |
|
|
221 |
/* Used to store the name service provider */
|
|
222 |
private static List<NameService> nameServices = null;
|
|
223 |
|
|
224 |
/* Used to store the best available hostname */
|
|
225 |
private transient String canonicalHostName = null;
|
|
226 |
|
|
227 |
/** use serialVersionUID from JDK 1.0.2 for interoperability */
|
|
228 |
private static final long serialVersionUID = 3286316764910316507L;
|
|
229 |
|
|
230 |
/*
|
|
231 |
* Load net library into runtime, and perform initializations.
|
|
232 |
*/
|
|
233 |
static {
|
|
234 |
preferIPv6Address = java.security.AccessController.doPrivileged(
|
|
235 |
new GetBooleanAction("java.net.preferIPv6Addresses")).booleanValue();
|
|
236 |
AccessController.doPrivileged(new LoadLibraryAction("net"));
|
|
237 |
init();
|
|
238 |
}
|
|
239 |
|
|
240 |
/**
|
|
241 |
* Constructor for the Socket.accept() method.
|
|
242 |
* This creates an empty InetAddress, which is filled in by
|
|
243 |
* the accept() method. This InetAddress, however, is not
|
|
244 |
* put in the address cache, since it is not created by name.
|
|
245 |
*/
|
|
246 |
InetAddress() {
|
|
247 |
}
|
|
248 |
|
|
249 |
/**
|
|
250 |
* Replaces the de-serialized object with an Inet4Address object.
|
|
251 |
*
|
|
252 |
* @return the alternate object to the de-serialized object.
|
|
253 |
*
|
|
254 |
* @throws ObjectStreamException if a new object replacing this
|
|
255 |
* object could not be created
|
|
256 |
*/
|
|
257 |
private Object readResolve() throws ObjectStreamException {
|
|
258 |
// will replace the deserialized 'this' object
|
|
259 |
return new Inet4Address(this.hostName, this.address);
|
|
260 |
}
|
|
261 |
|
|
262 |
/**
|
|
263 |
* Utility routine to check if the InetAddress is an
|
|
264 |
* IP multicast address.
|
|
265 |
* @return a <code>boolean</code> indicating if the InetAddress is
|
|
266 |
* an IP multicast address
|
|
267 |
* @since JDK1.1
|
|
268 |
*/
|
|
269 |
public boolean isMulticastAddress() {
|
|
270 |
return false;
|
|
271 |
}
|
|
272 |
|
|
273 |
/**
|
|
274 |
* Utility routine to check if the InetAddress in a wildcard address.
|
|
275 |
* @return a <code>boolean</code> indicating if the Inetaddress is
|
|
276 |
* a wildcard address.
|
|
277 |
* @since 1.4
|
|
278 |
*/
|
|
279 |
public boolean isAnyLocalAddress() {
|
|
280 |
return false;
|
|
281 |
}
|
|
282 |
|
|
283 |
/**
|
|
284 |
* Utility routine to check if the InetAddress is a loopback address.
|
|
285 |
*
|
|
286 |
* @return a <code>boolean</code> indicating if the InetAddress is
|
|
287 |
* a loopback address; or false otherwise.
|
|
288 |
* @since 1.4
|
|
289 |
*/
|
|
290 |
public boolean isLoopbackAddress() {
|
|
291 |
return false;
|
|
292 |
}
|
|
293 |
|
|
294 |
/**
|
|
295 |
* Utility routine to check if the InetAddress is an link local address.
|
|
296 |
*
|
|
297 |
* @return a <code>boolean</code> indicating if the InetAddress is
|
|
298 |
* a link local address; or false if address is not a link local unicast address.
|
|
299 |
* @since 1.4
|
|
300 |
*/
|
|
301 |
public boolean isLinkLocalAddress() {
|
|
302 |
return false;
|
|
303 |
}
|
|
304 |
|
|
305 |
/**
|
|
306 |
* Utility routine to check if the InetAddress is a site local address.
|
|
307 |
*
|
|
308 |
* @return a <code>boolean</code> indicating if the InetAddress is
|
|
309 |
* a site local address; or false if address is not a site local unicast address.
|
|
310 |
* @since 1.4
|
|
311 |
*/
|
|
312 |
public boolean isSiteLocalAddress() {
|
|
313 |
return false;
|
|
314 |
}
|
|
315 |
|
|
316 |
/**
|
|
317 |
* Utility routine to check if the multicast address has global scope.
|
|
318 |
*
|
|
319 |
* @return a <code>boolean</code> indicating if the address has
|
|
320 |
* is a multicast address of global scope, false if it is not
|
|
321 |
* of global scope or it is not a multicast address
|
|
322 |
* @since 1.4
|
|
323 |
*/
|
|
324 |
public boolean isMCGlobal() {
|
|
325 |
return false;
|
|
326 |
}
|
|
327 |
|
|
328 |
/**
|
|
329 |
* Utility routine to check if the multicast address has node scope.
|
|
330 |
*
|
|
331 |
* @return a <code>boolean</code> indicating if the address has
|
|
332 |
* is a multicast address of node-local scope, false if it is not
|
|
333 |
* of node-local scope or it is not a multicast address
|
|
334 |
* @since 1.4
|
|
335 |
*/
|
|
336 |
public boolean isMCNodeLocal() {
|
|
337 |
return false;
|
|
338 |
}
|
|
339 |
|
|
340 |
/**
|
|
341 |
* Utility routine to check if the multicast address has link scope.
|
|
342 |
*
|
|
343 |
* @return a <code>boolean</code> indicating if the address has
|
|
344 |
* is a multicast address of link-local scope, false if it is not
|
|
345 |
* of link-local scope or it is not a multicast address
|
|
346 |
* @since 1.4
|
|
347 |
*/
|
|
348 |
public boolean isMCLinkLocal() {
|
|
349 |
return false;
|
|
350 |
}
|
|
351 |
|
|
352 |
/**
|
|
353 |
* Utility routine to check if the multicast address has site scope.
|
|
354 |
*
|
|
355 |
* @return a <code>boolean</code> indicating if the address has
|
|
356 |
* is a multicast address of site-local scope, false if it is not
|
|
357 |
* of site-local scope or it is not a multicast address
|
|
358 |
* @since 1.4
|
|
359 |
*/
|
|
360 |
public boolean isMCSiteLocal() {
|
|
361 |
return false;
|
|
362 |
}
|
|
363 |
|
|
364 |
/**
|
|
365 |
* Utility routine to check if the multicast address has organization scope.
|
|
366 |
*
|
|
367 |
* @return a <code>boolean</code> indicating if the address has
|
|
368 |
* is a multicast address of organization-local scope,
|
|
369 |
* false if it is not of organization-local scope
|
|
370 |
* or it is not a multicast address
|
|
371 |
* @since 1.4
|
|
372 |
*/
|
|
373 |
public boolean isMCOrgLocal() {
|
|
374 |
return false;
|
|
375 |
}
|
|
376 |
|
|
377 |
|
|
378 |
/**
|
|
379 |
* Test whether that address is reachable. Best effort is made by the
|
|
380 |
* implementation to try to reach the host, but firewalls and server
|
|
381 |
* configuration may block requests resulting in a unreachable status
|
|
382 |
* while some specific ports may be accessible.
|
|
383 |
* A typical implementation will use ICMP ECHO REQUESTs if the
|
|
384 |
* privilege can be obtained, otherwise it will try to establish
|
|
385 |
* a TCP connection on port 7 (Echo) of the destination host.
|
|
386 |
* <p>
|
|
387 |
* The timeout value, in milliseconds, indicates the maximum amount of time
|
|
388 |
* the try should take. If the operation times out before getting an
|
|
389 |
* answer, the host is deemed unreachable. A negative value will result
|
|
390 |
* in an IllegalArgumentException being thrown.
|
|
391 |
*
|
|
392 |
* @param timeout the time, in milliseconds, before the call aborts
|
|
393 |
* @return a <code>boolean</code> indicating if the address is reachable.
|
|
394 |
* @throws IOException if a network error occurs
|
|
395 |
* @throws IllegalArgumentException if <code>timeout</code> is negative.
|
|
396 |
* @since 1.5
|
|
397 |
*/
|
|
398 |
public boolean isReachable(int timeout) throws IOException {
|
|
399 |
return isReachable(null, 0 , timeout);
|
|
400 |
}
|
|
401 |
|
|
402 |
/**
|
|
403 |
* Test whether that address is reachable. Best effort is made by the
|
|
404 |
* implementation to try to reach the host, but firewalls and server
|
|
405 |
* configuration may block requests resulting in a unreachable status
|
|
406 |
* while some specific ports may be accessible.
|
|
407 |
* A typical implementation will use ICMP ECHO REQUESTs if the
|
|
408 |
* privilege can be obtained, otherwise it will try to establish
|
|
409 |
* a TCP connection on port 7 (Echo) of the destination host.
|
|
410 |
* <p>
|
|
411 |
* The <code>network interface</code> and <code>ttl</code> parameters
|
|
412 |
* let the caller specify which network interface the test will go through
|
|
413 |
* and the maximum number of hops the packets should go through.
|
|
414 |
* A negative value for the <code>ttl</code> will result in an
|
|
415 |
* IllegalArgumentException being thrown.
|
|
416 |
* <p>
|
|
417 |
* The timeout value, in milliseconds, indicates the maximum amount of time
|
|
418 |
* the try should take. If the operation times out before getting an
|
|
419 |
* answer, the host is deemed unreachable. A negative value will result
|
|
420 |
* in an IllegalArgumentException being thrown.
|
|
421 |
*
|
|
422 |
* @param netif the NetworkInterface through which the
|
|
423 |
* test will be done, or null for any interface
|
|
424 |
* @param ttl the maximum numbers of hops to try or 0 for the
|
|
425 |
* default
|
|
426 |
* @param timeout the time, in milliseconds, before the call aborts
|
|
427 |
* @throws IllegalArgumentException if either <code>timeout</code>
|
|
428 |
* or <code>ttl</code> are negative.
|
|
429 |
* @return a <code>boolean</code>indicating if the address is reachable.
|
|
430 |
* @throws IOException if a network error occurs
|
|
431 |
* @since 1.5
|
|
432 |
*/
|
|
433 |
public boolean isReachable(NetworkInterface netif, int ttl,
|
|
434 |
int timeout) throws IOException {
|
|
435 |
if (ttl < 0)
|
|
436 |
throw new IllegalArgumentException("ttl can't be negative");
|
|
437 |
if (timeout < 0)
|
|
438 |
throw new IllegalArgumentException("timeout can't be negative");
|
|
439 |
|
|
440 |
return impl.isReachable(this, timeout, netif, ttl);
|
|
441 |
}
|
|
442 |
|
|
443 |
/**
|
|
444 |
* Gets the host name for this IP address.
|
|
445 |
*
|
|
446 |
* <p>If this InetAddress was created with a host name,
|
|
447 |
* this host name will be remembered and returned;
|
|
448 |
* otherwise, a reverse name lookup will be performed
|
|
449 |
* and the result will be returned based on the system
|
|
450 |
* configured name lookup service. If a lookup of the name service
|
|
451 |
* is required, call
|
|
452 |
* {@link #getCanonicalHostName() getCanonicalHostName}.
|
|
453 |
*
|
|
454 |
* <p>If there is a security manager, its
|
|
455 |
* <code>checkConnect</code> method is first called
|
|
456 |
* with the hostname and <code>-1</code>
|
|
457 |
* as its arguments to see if the operation is allowed.
|
|
458 |
* If the operation is not allowed, it will return
|
|
459 |
* the textual representation of the IP address.
|
|
460 |
*
|
|
461 |
* @return the host name for this IP address, or if the operation
|
|
462 |
* is not allowed by the security check, the textual
|
|
463 |
* representation of the IP address.
|
|
464 |
*
|
|
465 |
* @see InetAddress#getCanonicalHostName
|
|
466 |
* @see SecurityManager#checkConnect
|
|
467 |
*/
|
|
468 |
public String getHostName() {
|
|
469 |
return getHostName(true);
|
|
470 |
}
|
|
471 |
|
|
472 |
/**
|
|
473 |
* Returns the hostname for this address.
|
|
474 |
* If the host is equal to null, then this address refers to any
|
|
475 |
* of the local machine's available network addresses.
|
|
476 |
* this is package private so SocketPermission can make calls into
|
|
477 |
* here without a security check.
|
|
478 |
*
|
|
479 |
* <p>If there is a security manager, this method first
|
|
480 |
* calls its <code>checkConnect</code> method
|
|
481 |
* with the hostname and <code>-1</code>
|
|
482 |
* as its arguments to see if the calling code is allowed to know
|
|
483 |
* the hostname for this IP address, i.e., to connect to the host.
|
|
484 |
* If the operation is not allowed, it will return
|
|
485 |
* the textual representation of the IP address.
|
|
486 |
*
|
|
487 |
* @return the host name for this IP address, or if the operation
|
|
488 |
* is not allowed by the security check, the textual
|
|
489 |
* representation of the IP address.
|
|
490 |
*
|
|
491 |
* @param check make security check if true
|
|
492 |
*
|
|
493 |
* @see SecurityManager#checkConnect
|
|
494 |
*/
|
|
495 |
String getHostName(boolean check) {
|
|
496 |
if (hostName == null) {
|
|
497 |
hostName = InetAddress.getHostFromNameService(this, check);
|
|
498 |
}
|
|
499 |
return hostName;
|
|
500 |
}
|
|
501 |
|
|
502 |
/**
|
|
503 |
* Gets the fully qualified domain name for this IP address.
|
|
504 |
* Best effort method, meaning we may not be able to return
|
|
505 |
* the FQDN depending on the underlying system configuration.
|
|
506 |
*
|
|
507 |
* <p>If there is a security manager, this method first
|
|
508 |
* calls its <code>checkConnect</code> method
|
|
509 |
* with the hostname and <code>-1</code>
|
|
510 |
* as its arguments to see if the calling code is allowed to know
|
|
511 |
* the hostname for this IP address, i.e., to connect to the host.
|
|
512 |
* If the operation is not allowed, it will return
|
|
513 |
* the textual representation of the IP address.
|
|
514 |
*
|
|
515 |
* @return the fully qualified domain name for this IP address,
|
|
516 |
* or if the operation is not allowed by the security check,
|
|
517 |
* the textual representation of the IP address.
|
|
518 |
*
|
|
519 |
* @see SecurityManager#checkConnect
|
|
520 |
*
|
|
521 |
* @since 1.4
|
|
522 |
*/
|
|
523 |
public String getCanonicalHostName() {
|
|
524 |
if (canonicalHostName == null) {
|
|
525 |
canonicalHostName =
|
|
526 |
InetAddress.getHostFromNameService(this, true);
|
|
527 |
}
|
|
528 |
return canonicalHostName;
|
|
529 |
}
|
|
530 |
|
|
531 |
/**
|
|
532 |
* Returns the hostname for this address.
|
|
533 |
*
|
|
534 |
* <p>If there is a security manager, this method first
|
|
535 |
* calls its <code>checkConnect</code> method
|
|
536 |
* with the hostname and <code>-1</code>
|
|
537 |
* as its arguments to see if the calling code is allowed to know
|
|
538 |
* the hostname for this IP address, i.e., to connect to the host.
|
|
539 |
* If the operation is not allowed, it will return
|
|
540 |
* the textual representation of the IP address.
|
|
541 |
*
|
|
542 |
* @return the host name for this IP address, or if the operation
|
|
543 |
* is not allowed by the security check, the textual
|
|
544 |
* representation of the IP address.
|
|
545 |
*
|
|
546 |
* @param check make security check if true
|
|
547 |
*
|
|
548 |
* @see SecurityManager#checkConnect
|
|
549 |
*/
|
|
550 |
private static String getHostFromNameService(InetAddress addr, boolean check) {
|
|
551 |
String host = null;
|
|
552 |
for (NameService nameService : nameServices) {
|
|
553 |
try {
|
|
554 |
// first lookup the hostname
|
|
555 |
host = nameService.getHostByAddr(addr.getAddress());
|
|
556 |
|
|
557 |
/* check to see if calling code is allowed to know
|
|
558 |
* the hostname for this IP address, ie, connect to the host
|
|
559 |
*/
|
|
560 |
if (check) {
|
|
561 |
SecurityManager sec = System.getSecurityManager();
|
|
562 |
if (sec != null) {
|
|
563 |
sec.checkConnect(host, -1);
|
|
564 |
}
|
|
565 |
}
|
|
566 |
|
|
567 |
/* now get all the IP addresses for this hostname,
|
|
568 |
* and make sure one of them matches the original IP
|
|
569 |
* address. We do this to try and prevent spoofing.
|
|
570 |
*/
|
|
571 |
|
|
572 |
InetAddress[] arr = InetAddress.getAllByName0(host, check);
|
|
573 |
boolean ok = false;
|
|
574 |
|
|
575 |
if(arr != null) {
|
|
576 |
for(int i = 0; !ok && i < arr.length; i++) {
|
|
577 |
ok = addr.equals(arr[i]);
|
|
578 |
}
|
|
579 |
}
|
|
580 |
|
|
581 |
//XXX: if it looks a spoof just return the address?
|
|
582 |
if (!ok) {
|
|
583 |
host = addr.getHostAddress();
|
|
584 |
return host;
|
|
585 |
}
|
|
586 |
|
|
587 |
break;
|
|
588 |
|
|
589 |
} catch (SecurityException e) {
|
|
590 |
host = addr.getHostAddress();
|
|
591 |
break;
|
|
592 |
} catch (UnknownHostException e) {
|
|
593 |
host = addr.getHostAddress();
|
|
594 |
// let next provider resolve the hostname
|
|
595 |
}
|
|
596 |
}
|
|
597 |
|
|
598 |
return host;
|
|
599 |
}
|
|
600 |
|
|
601 |
/**
|
|
602 |
* Returns the raw IP address of this <code>InetAddress</code>
|
|
603 |
* object. The result is in network byte order: the highest order
|
|
604 |
* byte of the address is in <code>getAddress()[0]</code>.
|
|
605 |
*
|
|
606 |
* @return the raw IP address of this object.
|
|
607 |
*/
|
|
608 |
public byte[] getAddress() {
|
|
609 |
return null;
|
|
610 |
}
|
|
611 |
|
|
612 |
/**
|
|
613 |
* Returns the IP address string in textual presentation.
|
|
614 |
*
|
|
615 |
* @return the raw IP address in a string format.
|
|
616 |
* @since JDK1.0.2
|
|
617 |
*/
|
|
618 |
public String getHostAddress() {
|
|
619 |
return null;
|
|
620 |
}
|
|
621 |
|
|
622 |
/**
|
|
623 |
* Returns a hashcode for this IP address.
|
|
624 |
*
|
|
625 |
* @return a hash code value for this IP address.
|
|
626 |
*/
|
|
627 |
public int hashCode() {
|
|
628 |
return -1;
|
|
629 |
}
|
|
630 |
|
|
631 |
/**
|
|
632 |
* Compares this object against the specified object.
|
|
633 |
* The result is <code>true</code> if and only if the argument is
|
|
634 |
* not <code>null</code> and it represents the same IP address as
|
|
635 |
* this object.
|
|
636 |
* <p>
|
|
637 |
* Two instances of <code>InetAddress</code> represent the same IP
|
|
638 |
* address if the length of the byte arrays returned by
|
|
639 |
* <code>getAddress</code> is the same for both, and each of the
|
|
640 |
* array components is the same for the byte arrays.
|
|
641 |
*
|
|
642 |
* @param obj the object to compare against.
|
|
643 |
* @return <code>true</code> if the objects are the same;
|
|
644 |
* <code>false</code> otherwise.
|
|
645 |
* @see java.net.InetAddress#getAddress()
|
|
646 |
*/
|
|
647 |
public boolean equals(Object obj) {
|
|
648 |
return false;
|
|
649 |
}
|
|
650 |
|
|
651 |
/**
|
|
652 |
* Converts this IP address to a <code>String</code>. The
|
|
653 |
* string returned is of the form: hostname / literal IP
|
|
654 |
* address.
|
|
655 |
*
|
|
656 |
* If the host name is unresolved, no reverse name service lookup
|
|
657 |
* is performed. The hostname part will be represented by an empty string.
|
|
658 |
*
|
|
659 |
* @return a string representation of this IP address.
|
|
660 |
*/
|
|
661 |
public String toString() {
|
|
662 |
return ((hostName != null) ? hostName : "")
|
|
663 |
+ "/" + getHostAddress();
|
|
664 |
}
|
|
665 |
|
|
666 |
/*
|
|
667 |
* Cached addresses - our own litle nis, not!
|
|
668 |
*/
|
|
669 |
private static Cache addressCache = new Cache(Cache.Type.Positive);
|
|
670 |
|
|
671 |
private static Cache negativeCache = new Cache(Cache.Type.Negative);
|
|
672 |
|
|
673 |
private static boolean addressCacheInit = false;
|
|
674 |
|
|
675 |
static InetAddress[] unknown_array; // put THIS in cache
|
|
676 |
|
|
677 |
static InetAddressImpl impl;
|
|
678 |
|
|
679 |
private static HashMap lookupTable = new HashMap();
|
|
680 |
|
|
681 |
/**
|
|
682 |
* Represents a cache entry
|
|
683 |
*/
|
|
684 |
static final class CacheEntry {
|
|
685 |
|
|
686 |
CacheEntry(Object address, long expiration) {
|
|
687 |
this.address = address;
|
|
688 |
this.expiration = expiration;
|
|
689 |
}
|
|
690 |
|
|
691 |
Object address;
|
|
692 |
long expiration;
|
|
693 |
}
|
|
694 |
|
|
695 |
/**
|
|
696 |
* A cache that manages entries based on a policy specified
|
|
697 |
* at creation time.
|
|
698 |
*/
|
|
699 |
static final class Cache {
|
|
700 |
private LinkedHashMap cache;
|
|
701 |
private Type type;
|
|
702 |
|
|
703 |
enum Type {Positive, Negative};
|
|
704 |
|
|
705 |
/**
|
|
706 |
* Create cache
|
|
707 |
*/
|
|
708 |
public Cache(Type type) {
|
|
709 |
this.type = type;
|
|
710 |
cache = new LinkedHashMap();
|
|
711 |
}
|
|
712 |
|
|
713 |
private int getPolicy() {
|
|
714 |
if (type == Type.Positive) {
|
|
715 |
return InetAddressCachePolicy.get();
|
|
716 |
} else {
|
|
717 |
return InetAddressCachePolicy.getNegative();
|
|
718 |
}
|
|
719 |
}
|
|
720 |
|
|
721 |
/**
|
|
722 |
* Add an entry to the cache. If there's already an
|
|
723 |
* entry then for this host then the entry will be
|
|
724 |
* replaced.
|
|
725 |
*/
|
|
726 |
public Cache put(String host, Object address) {
|
|
727 |
int policy = getPolicy();
|
|
728 |
if (policy == InetAddressCachePolicy.NEVER) {
|
|
729 |
return this;
|
|
730 |
}
|
|
731 |
|
|
732 |
// purge any expired entries
|
|
733 |
|
|
734 |
if (policy != InetAddressCachePolicy.FOREVER) {
|
|
735 |
|
|
736 |
// As we iterate in insertion order we can
|
|
737 |
// terminate when a non-expired entry is found.
|
|
738 |
LinkedList expired = new LinkedList();
|
|
739 |
Iterator i = cache.keySet().iterator();
|
|
740 |
long now = System.currentTimeMillis();
|
|
741 |
while (i.hasNext()) {
|
|
742 |
String key = (String)i.next();
|
|
743 |
CacheEntry entry = (CacheEntry)cache.get(key);
|
|
744 |
|
|
745 |
if (entry.expiration >= 0 && entry.expiration < now) {
|
|
746 |
expired.add(key);
|
|
747 |
} else {
|
|
748 |
break;
|
|
749 |
}
|
|
750 |
}
|
|
751 |
|
|
752 |
i = expired.iterator();
|
|
753 |
while (i.hasNext()) {
|
|
754 |
cache.remove(i.next());
|
|
755 |
}
|
|
756 |
}
|
|
757 |
|
|
758 |
// create new entry and add it to the cache
|
|
759 |
// -- as a HashMap replaces existing entries we
|
|
760 |
// don't need to explicitly check if there is
|
|
761 |
// already an entry for this host.
|
|
762 |
long expiration;
|
|
763 |
if (policy == InetAddressCachePolicy.FOREVER) {
|
|
764 |
expiration = -1;
|
|
765 |
} else {
|
|
766 |
expiration = System.currentTimeMillis() + (policy * 1000);
|
|
767 |
}
|
|
768 |
CacheEntry entry = new CacheEntry(address, expiration);
|
|
769 |
cache.put(host, entry);
|
|
770 |
return this;
|
|
771 |
}
|
|
772 |
|
|
773 |
/**
|
|
774 |
* Query the cache for the specific host. If found then
|
|
775 |
* return its CacheEntry, or null if not found.
|
|
776 |
*/
|
|
777 |
public CacheEntry get(String host) {
|
|
778 |
int policy = getPolicy();
|
|
779 |
if (policy == InetAddressCachePolicy.NEVER) {
|
|
780 |
return null;
|
|
781 |
}
|
|
782 |
CacheEntry entry = (CacheEntry)cache.get(host);
|
|
783 |
|
|
784 |
// check if entry has expired
|
|
785 |
if (entry != null && policy != InetAddressCachePolicy.FOREVER) {
|
|
786 |
if (entry.expiration >= 0 &&
|
|
787 |
entry.expiration < System.currentTimeMillis()) {
|
|
788 |
cache.remove(host);
|
|
789 |
entry = null;
|
|
790 |
}
|
|
791 |
}
|
|
792 |
|
|
793 |
return entry;
|
|
794 |
}
|
|
795 |
}
|
|
796 |
|
|
797 |
/*
|
|
798 |
* Initialize cache and insert anyLocalAddress into the
|
|
799 |
* unknown array with no expiry.
|
|
800 |
*/
|
|
801 |
private static void cacheInitIfNeeded() {
|
|
802 |
assert Thread.holdsLock(addressCache);
|
|
803 |
if (addressCacheInit) {
|
|
804 |
return;
|
|
805 |
}
|
|
806 |
unknown_array = new InetAddress[1];
|
|
807 |
unknown_array[0] = impl.anyLocalAddress();
|
|
808 |
|
|
809 |
addressCache.put(impl.anyLocalAddress().getHostName(),
|
|
810 |
unknown_array);
|
|
811 |
|
|
812 |
addressCacheInit = true;
|
|
813 |
}
|
|
814 |
|
|
815 |
/*
|
|
816 |
* Cache the given hostname and address.
|
|
817 |
*/
|
|
818 |
private static void cacheAddress(String hostname, Object address,
|
|
819 |
boolean success) {
|
|
820 |
hostname = hostname.toLowerCase();
|
|
821 |
synchronized (addressCache) {
|
|
822 |
cacheInitIfNeeded();
|
|
823 |
if (success) {
|
|
824 |
addressCache.put(hostname, address);
|
|
825 |
} else {
|
|
826 |
negativeCache.put(hostname, address);
|
|
827 |
}
|
|
828 |
}
|
|
829 |
}
|
|
830 |
|
|
831 |
/*
|
|
832 |
* Lookup hostname in cache (positive & negative cache). If
|
|
833 |
* found return address, null if not found.
|
|
834 |
*/
|
|
835 |
private static Object getCachedAddress(String hostname) {
|
|
836 |
hostname = hostname.toLowerCase();
|
|
837 |
|
|
838 |
// search both positive & negative caches
|
|
839 |
|
|
840 |
synchronized (addressCache) {
|
|
841 |
CacheEntry entry;
|
|
842 |
|
|
843 |
cacheInitIfNeeded();
|
|
844 |
|
|
845 |
entry = addressCache.get(hostname);
|
|
846 |
if (entry == null) {
|
|
847 |
entry = negativeCache.get(hostname);
|
|
848 |
}
|
|
849 |
|
|
850 |
if (entry != null) {
|
|
851 |
return entry.address;
|
|
852 |
}
|
|
853 |
}
|
|
854 |
|
|
855 |
// not found
|
|
856 |
return null;
|
|
857 |
}
|
|
858 |
|
|
859 |
private static NameService createNSProvider(String provider) {
|
|
860 |
if (provider == null)
|
|
861 |
return null;
|
|
862 |
|
|
863 |
NameService nameService = null;
|
|
864 |
if (provider.equals("default")) {
|
|
865 |
// initialize the default name service
|
|
866 |
nameService = new NameService() {
|
|
867 |
public InetAddress[] lookupAllHostAddr(String host)
|
|
868 |
throws UnknownHostException {
|
|
869 |
return impl.lookupAllHostAddr(host);
|
|
870 |
}
|
|
871 |
public String getHostByAddr(byte[] addr)
|
|
872 |
throws UnknownHostException {
|
|
873 |
return impl.getHostByAddr(addr);
|
|
874 |
}
|
|
875 |
};
|
|
876 |
} else {
|
|
877 |
final String providerName = provider;
|
|
878 |
try {
|
|
879 |
nameService = java.security.AccessController.doPrivileged(
|
|
880 |
new java.security.PrivilegedExceptionAction<NameService>() {
|
|
881 |
public NameService run() {
|
|
882 |
Iterator itr = Service.providers(NameServiceDescriptor.class);
|
|
883 |
while (itr.hasNext()) {
|
|
884 |
NameServiceDescriptor nsd
|
|
885 |
= (NameServiceDescriptor)itr.next();
|
|
886 |
if (providerName.
|
|
887 |
equalsIgnoreCase(nsd.getType()+","
|
|
888 |
+nsd.getProviderName())) {
|
|
889 |
try {
|
|
890 |
return nsd.createNameService();
|
|
891 |
} catch (Exception e) {
|
|
892 |
e.printStackTrace();
|
|
893 |
System.err.println(
|
|
894 |
"Cannot create name service:"
|
|
895 |
+providerName+": " + e);
|
|
896 |
}
|
|
897 |
}
|
|
898 |
}
|
|
899 |
|
|
900 |
return null;
|
|
901 |
}
|
|
902 |
}
|
|
903 |
);
|
|
904 |
} catch (java.security.PrivilegedActionException e) {
|
|
905 |
}
|
|
906 |
}
|
|
907 |
|
|
908 |
return nameService;
|
|
909 |
}
|
|
910 |
|
|
911 |
static {
|
|
912 |
// create the impl
|
|
913 |
impl = (new InetAddressImplFactory()).create();
|
|
914 |
|
|
915 |
// get name service if provided and requested
|
|
916 |
String provider = null;;
|
|
917 |
String propPrefix = "sun.net.spi.nameservice.provider.";
|
|
918 |
int n = 1;
|
|
919 |
nameServices = new ArrayList<NameService>();
|
|
920 |
provider = AccessController.doPrivileged(
|
|
921 |
new GetPropertyAction(propPrefix + n));
|
|
922 |
while (provider != null) {
|
|
923 |
NameService ns = createNSProvider(provider);
|
|
924 |
if (ns != null)
|
|
925 |
nameServices.add(ns);
|
|
926 |
|
|
927 |
n++;
|
|
928 |
provider = AccessController.doPrivileged(
|
|
929 |
new GetPropertyAction(propPrefix + n));
|
|
930 |
}
|
|
931 |
|
|
932 |
// if not designate any name services provider,
|
|
933 |
// creat a default one
|
|
934 |
if (nameServices.size() == 0) {
|
|
935 |
NameService ns = createNSProvider("default");
|
|
936 |
nameServices.add(ns);
|
|
937 |
}
|
|
938 |
}
|
|
939 |
|
|
940 |
/**
|
|
941 |
* Create an InetAddress based on the provided host name and IP address
|
|
942 |
* No name service is checked for the validity of the address.
|
|
943 |
*
|
|
944 |
* <p> The host name can either be a machine name, such as
|
|
945 |
* "<code>java.sun.com</code>", or a textual representation of its IP
|
|
946 |
* address.
|
|
947 |
* <p> No validity checking is done on the host name either.
|
|
948 |
*
|
|
949 |
* <p> If addr specifies an IPv4 address an instance of Inet4Address
|
|
950 |
* will be returned; otherwise, an instance of Inet6Address
|
|
951 |
* will be returned.
|
|
952 |
*
|
|
953 |
* <p> IPv4 address byte array must be 4 bytes long and IPv6 byte array
|
|
954 |
* must be 16 bytes long
|
|
955 |
*
|
|
956 |
* @param host the specified host
|
|
957 |
* @param addr the raw IP address in network byte order
|
|
958 |
* @return an InetAddress object created from the raw IP address.
|
|
959 |
* @exception UnknownHostException if IP address is of illegal length
|
|
960 |
* @since 1.4
|
|
961 |
*/
|
|
962 |
public static InetAddress getByAddress(String host, byte[] addr)
|
|
963 |
throws UnknownHostException {
|
|
964 |
if (host != null && host.length() > 0 && host.charAt(0) == '[') {
|
|
965 |
if (host.charAt(host.length()-1) == ']') {
|
|
966 |
host = host.substring(1, host.length() -1);
|
|
967 |
}
|
|
968 |
}
|
|
969 |
if (addr != null) {
|
|
970 |
if (addr.length == Inet4Address.INADDRSZ) {
|
|
971 |
return new Inet4Address(host, addr);
|
|
972 |
} else if (addr.length == Inet6Address.INADDRSZ) {
|
|
973 |
byte[] newAddr
|
|
974 |
= IPAddressUtil.convertFromIPv4MappedAddress(addr);
|
|
975 |
if (newAddr != null) {
|
|
976 |
return new Inet4Address(host, newAddr);
|
|
977 |
} else {
|
|
978 |
return new Inet6Address(host, addr);
|
|
979 |
}
|
|
980 |
}
|
|
981 |
}
|
|
982 |
throw new UnknownHostException("addr is of illegal length");
|
|
983 |
}
|
|
984 |
|
|
985 |
|
|
986 |
/**
|
|
987 |
* Determines the IP address of a host, given the host's name.
|
|
988 |
*
|
|
989 |
* <p> The host name can either be a machine name, such as
|
|
990 |
* "<code>java.sun.com</code>", or a textual representation of its
|
|
991 |
* IP address. If a literal IP address is supplied, only the
|
|
992 |
* validity of the address format is checked.
|
|
993 |
*
|
|
994 |
* <p> For <code>host</code> specified in literal IPv6 address,
|
|
995 |
* either the form defined in RFC 2732 or the literal IPv6 address
|
|
996 |
* format defined in RFC 2373 is accepted. IPv6 scoped addresses are also
|
|
997 |
* supported. See <a href="Inet6Address.html#scoped">here</a> for a description of IPv6
|
|
998 |
* scoped addresses.
|
|
999 |
*
|
|
1000 |
* <p> If the host is <tt>null</tt> then an <tt>InetAddress</tt>
|
|
1001 |
* representing an address of the loopback interface is returned.
|
|
1002 |
* See <a href="http://www.ietf.org/rfc/rfc3330.txt">RFC 3330</a>
|
|
1003 |
* section 2 and <a href="http://www.ietf.org/rfc/rfc2373.txt">RFC 2373</a>
|
|
1004 |
* section 2.5.3. </p>
|
|
1005 |
*
|
|
1006 |
* @param host the specified host, or <code>null</code>.
|
|
1007 |
* @return an IP address for the given host name.
|
|
1008 |
* @exception UnknownHostException if no IP address for the
|
|
1009 |
* <code>host</code> could be found, or if a scope_id was specified
|
|
1010 |
* for a global IPv6 address.
|
|
1011 |
* @exception SecurityException if a security manager exists
|
|
1012 |
* and its checkConnect method doesn't allow the operation
|
|
1013 |
*/
|
|
1014 |
public static InetAddress getByName(String host)
|
|
1015 |
throws UnknownHostException {
|
|
1016 |
return InetAddress.getAllByName(host)[0];
|
|
1017 |
}
|
|
1018 |
|
|
1019 |
/**
|
|
1020 |
* Given the name of a host, returns an array of its IP addresses,
|
|
1021 |
* based on the configured name service on the system.
|
|
1022 |
*
|
|
1023 |
* <p> The host name can either be a machine name, such as
|
|
1024 |
* "<code>java.sun.com</code>", or a textual representation of its IP
|
|
1025 |
* address. If a literal IP address is supplied, only the
|
|
1026 |
* validity of the address format is checked.
|
|
1027 |
*
|
|
1028 |
* <p> For <code>host</code> specified in <i>literal IPv6 address</i>,
|
|
1029 |
* either the form defined in RFC 2732 or the literal IPv6 address
|
|
1030 |
* format defined in RFC 2373 is accepted. A literal IPv6 address may
|
|
1031 |
* also be qualified by appending a scoped zone identifier or scope_id.
|
|
1032 |
* The syntax and usage of scope_ids is described
|
|
1033 |
* <a href="Inet6Address.html#scoped">here</a>.
|
|
1034 |
* <p> If the host is <tt>null</tt> then an <tt>InetAddress</tt>
|
|
1035 |
* representing an address of the loopback interface is returned.
|
|
1036 |
* See <a href="http://www.ietf.org/rfc/rfc3330.txt">RFC 3330</a>
|
|
1037 |
* section 2 and <a href="http://www.ietf.org/rfc/rfc2373.txt">RFC 2373</a>
|
|
1038 |
* section 2.5.3. </p>
|
|
1039 |
*
|
|
1040 |
* <p> If there is a security manager and <code>host</code> is not
|
|
1041 |
* null and <code>host.length() </code> is not equal to zero, the
|
|
1042 |
* security manager's
|
|
1043 |
* <code>checkConnect</code> method is called
|
|
1044 |
* with the hostname and <code>-1</code>
|
|
1045 |
* as its arguments to see if the operation is allowed.
|
|
1046 |
*
|
|
1047 |
* @param host the name of the host, or <code>null</code>.
|
|
1048 |
* @return an array of all the IP addresses for a given host name.
|
|
1049 |
*
|
|
1050 |
* @exception UnknownHostException if no IP address for the
|
|
1051 |
* <code>host</code> could be found, or if a scope_id was specified
|
|
1052 |
* for a global IPv6 address.
|
|
1053 |
* @exception SecurityException if a security manager exists and its
|
|
1054 |
* <code>checkConnect</code> method doesn't allow the operation.
|
|
1055 |
*
|
|
1056 |
* @see SecurityManager#checkConnect
|
|
1057 |
*/
|
|
1058 |
public static InetAddress[] getAllByName(String host)
|
|
1059 |
throws UnknownHostException {
|
|
1060 |
|
|
1061 |
if (host == null || host.length() == 0) {
|
|
1062 |
InetAddress[] ret = new InetAddress[1];
|
|
1063 |
ret[0] = impl.loopbackAddress();
|
|
1064 |
return ret;
|
|
1065 |
}
|
|
1066 |
|
|
1067 |
boolean ipv6Expected = false;
|
|
1068 |
if (host.charAt(0) == '[') {
|
|
1069 |
// This is supposed to be an IPv6 litteral
|
|
1070 |
if (host.length() > 2 && host.charAt(host.length()-1) == ']') {
|
|
1071 |
host = host.substring(1, host.length() -1);
|
|
1072 |
ipv6Expected = true;
|
|
1073 |
} else {
|
|
1074 |
// This was supposed to be a IPv6 address, but it's not!
|
|
1075 |
throw new UnknownHostException(host);
|
|
1076 |
}
|
|
1077 |
}
|
|
1078 |
|
|
1079 |
// if host is an IP address, we won't do further lookup
|
|
1080 |
if (Character.digit(host.charAt(0), 16) != -1
|
|
1081 |
|| (host.charAt(0) == ':')) {
|
|
1082 |
byte[] addr = null;
|
|
1083 |
int numericZone = -1;
|
|
1084 |
String ifname = null;
|
|
1085 |
// see if it is IPv4 address
|
|
1086 |
addr = IPAddressUtil.textToNumericFormatV4(host);
|
|
1087 |
if (addr == null) {
|
|
1088 |
// see if it is IPv6 address
|
|
1089 |
// Check if a numeric or string zone id is present
|
|
1090 |
int pos;
|
|
1091 |
if ((pos=host.indexOf ("%")) != -1) {
|
|
1092 |
numericZone = checkNumericZone (host);
|
|
1093 |
if (numericZone == -1) { /* remainder of string must be an ifname */
|
|
1094 |
ifname = host.substring (pos+1);
|
|
1095 |
}
|
|
1096 |
}
|
|
1097 |
addr = IPAddressUtil.textToNumericFormatV6(host);
|
|
1098 |
} else if (ipv6Expected) {
|
|
1099 |
// Means an IPv4 litteral between brackets!
|
|
1100 |
throw new UnknownHostException("["+host+"]");
|
|
1101 |
}
|
|
1102 |
InetAddress[] ret = new InetAddress[1];
|
|
1103 |
if(addr != null) {
|
|
1104 |
if (addr.length == Inet4Address.INADDRSZ) {
|
|
1105 |
ret[0] = new Inet4Address(null, addr);
|
|
1106 |
} else {
|
|
1107 |
if (ifname != null) {
|
|
1108 |
ret[0] = new Inet6Address(null, addr, ifname);
|
|
1109 |
} else {
|
|
1110 |
ret[0] = new Inet6Address(null, addr, numericZone);
|
|
1111 |
}
|
|
1112 |
}
|
|
1113 |
return ret;
|
|
1114 |
}
|
|
1115 |
} else if (ipv6Expected) {
|
|
1116 |
// We were expecting an IPv6 Litteral, but got something else
|
|
1117 |
throw new UnknownHostException("["+host+"]");
|
|
1118 |
}
|
|
1119 |
return getAllByName0(host);
|
|
1120 |
}
|
|
1121 |
|
|
1122 |
/**
|
|
1123 |
* Returns the loopback address.
|
|
1124 |
* <p>
|
|
1125 |
* The InetAddress returned will represent the IPv4
|
|
1126 |
* loopback address, 127.0.0.1, or the IPv6 loopback
|
|
1127 |
* address, ::1. The IPv4 loopback address returned
|
|
1128 |
* is only one of many in the form 127.*.*.*
|
|
1129 |
*
|
|
1130 |
* @return the InetAddress loopback instance.
|
|
1131 |
* @since 1.7
|
|
1132 |
*/
|
|
1133 |
public static InetAddress getLoopbackAddress() {
|
|
1134 |
return impl.loopbackAddress();
|
|
1135 |
}
|
|
1136 |
|
|
1137 |
|
|
1138 |
/**
|
|
1139 |
* check if the literal address string has %nn appended
|
|
1140 |
* returns -1 if not, or the numeric value otherwise.
|
|
1141 |
*
|
|
1142 |
* %nn may also be a string that represents the displayName of
|
|
1143 |
* a currently available NetworkInterface.
|
|
1144 |
*/
|
|
1145 |
private static int checkNumericZone (String s) throws UnknownHostException {
|
|
1146 |
int percent = s.indexOf ('%');
|
|
1147 |
int slen = s.length();
|
|
1148 |
int digit, zone=0;
|
|
1149 |
if (percent == -1) {
|
|
1150 |
return -1;
|
|
1151 |
}
|
|
1152 |
for (int i=percent+1; i<slen; i++) {
|
|
1153 |
char c = s.charAt(i);
|
|
1154 |
if (c == ']') {
|
|
1155 |
if (i == percent+1) {
|
|
1156 |
/* empty per-cent field */
|
|
1157 |
return -1;
|
|
1158 |
}
|
|
1159 |
break;
|
|
1160 |
}
|
|
1161 |
if ((digit = Character.digit (c, 10)) < 0) {
|
|
1162 |
return -1;
|
|
1163 |
}
|
|
1164 |
zone = (zone * 10) + digit;
|
|
1165 |
}
|
|
1166 |
return zone;
|
|
1167 |
}
|
|
1168 |
|
|
1169 |
private static InetAddress[] getAllByName0 (String host)
|
|
1170 |
throws UnknownHostException
|
|
1171 |
{
|
|
1172 |
return getAllByName0(host, true);
|
|
1173 |
}
|
|
1174 |
|
|
1175 |
/**
|
|
1176 |
* package private so SocketPermission can call it
|
|
1177 |
*/
|
|
1178 |
static InetAddress[] getAllByName0 (String host, boolean check)
|
|
1179 |
throws UnknownHostException {
|
|
1180 |
/* If it gets here it is presumed to be a hostname */
|
|
1181 |
/* Cache.get can return: null, unknownAddress, or InetAddress[] */
|
|
1182 |
Object obj = null;
|
|
1183 |
Object objcopy = null;
|
|
1184 |
|
|
1185 |
/* make sure the connection to the host is allowed, before we
|
|
1186 |
* give out a hostname
|
|
1187 |
*/
|
|
1188 |
if (check) {
|
|
1189 |
SecurityManager security = System.getSecurityManager();
|
|
1190 |
if (security != null) {
|
|
1191 |
security.checkConnect(host, -1);
|
|
1192 |
}
|
|
1193 |
}
|
|
1194 |
|
|
1195 |
obj = getCachedAddress(host);
|
|
1196 |
|
|
1197 |
/* If no entry in cache, then do the host lookup */
|
|
1198 |
if (obj == null) {
|
|
1199 |
obj = getAddressFromNameService(host);
|
|
1200 |
}
|
|
1201 |
|
|
1202 |
if (obj == unknown_array)
|
|
1203 |
throw new UnknownHostException(host);
|
|
1204 |
|
|
1205 |
/* Make a copy of the InetAddress array */
|
|
1206 |
objcopy = ((InetAddress [])obj).clone();
|
|
1207 |
|
|
1208 |
return (InetAddress [])objcopy;
|
|
1209 |
}
|
|
1210 |
|
|
1211 |
private static Object getAddressFromNameService(String host)
|
|
1212 |
throws UnknownHostException
|
|
1213 |
{
|
|
1214 |
Object obj = null;
|
|
1215 |
boolean success = false;
|
|
1216 |
UnknownHostException ex = null;
|
|
1217 |
|
|
1218 |
// Check whether the host is in the lookupTable.
|
|
1219 |
// 1) If the host isn't in the lookupTable when
|
|
1220 |
// checkLookupTable() is called, checkLookupTable()
|
|
1221 |
// would add the host in the lookupTable and
|
|
1222 |
// return null. So we will do the lookup.
|
|
1223 |
// 2) If the host is in the lookupTable when
|
|
1224 |
// checkLookupTable() is called, the current thread
|
|
1225 |
// would be blocked until the host is removed
|
|
1226 |
// from the lookupTable. Then this thread
|
|
1227 |
// should try to look up the addressCache.
|
|
1228 |
// i) if it found the address in the
|
|
1229 |
// addressCache, checkLookupTable() would
|
|
1230 |
// return the address.
|
|
1231 |
// ii) if it didn't find the address in the
|
|
1232 |
// addressCache for any reason,
|
|
1233 |
// it should add the host in the
|
|
1234 |
// lookupTable and return null so the
|
|
1235 |
// following code would do a lookup itself.
|
|
1236 |
if ((obj = checkLookupTable(host)) == null) {
|
|
1237 |
// This is the first thread which looks up the address
|
|
1238 |
// this host or the cache entry for this host has been
|
|
1239 |
// expired so this thread should do the lookup.
|
|
1240 |
for (NameService nameService : nameServices) {
|
|
1241 |
try {
|
|
1242 |
/*
|
|
1243 |
* Do not put the call to lookup() inside the
|
|
1244 |
* constructor. if you do you will still be
|
|
1245 |
* allocating space when the lookup fails.
|
|
1246 |
*/
|
|
1247 |
|
|
1248 |
obj = nameService.lookupAllHostAddr(host);
|
|
1249 |
success = true;
|
|
1250 |
break;
|
|
1251 |
} catch (UnknownHostException uhe) {
|
|
1252 |
if (host.equalsIgnoreCase("localhost")) {
|
|
1253 |
InetAddress[] local = new InetAddress[] { impl.loopbackAddress() };
|
|
1254 |
obj = local;
|
|
1255 |
success = true;
|
|
1256 |
break;
|
|
1257 |
}
|
|
1258 |
else {
|
|
1259 |
obj = unknown_array;
|
|
1260 |
success = false;
|
|
1261 |
ex = uhe;
|
|
1262 |
}
|
|
1263 |
}
|
|
1264 |
}
|
|
1265 |
|
|
1266 |
// Cache the address.
|
|
1267 |
cacheAddress(host, obj, success);
|
|
1268 |
// Delete the host from the lookupTable, and
|
|
1269 |
// notify all threads waiting for the monitor
|
|
1270 |
// for lookupTable.
|
|
1271 |
updateLookupTable(host);
|
|
1272 |
if (!success && ex != null)
|
|
1273 |
throw ex;
|
|
1274 |
}
|
|
1275 |
|
|
1276 |
return obj;
|
|
1277 |
}
|
|
1278 |
|
|
1279 |
|
|
1280 |
private static Object checkLookupTable(String host) {
|
|
1281 |
// make sure obj is null.
|
|
1282 |
Object obj = null;
|
|
1283 |
|
|
1284 |
synchronized (lookupTable) {
|
|
1285 |
// If the host isn't in the lookupTable, add it in the
|
|
1286 |
// lookuptable and return null. The caller should do
|
|
1287 |
// the lookup.
|
|
1288 |
if (lookupTable.containsKey(host) == false) {
|
|
1289 |
lookupTable.put(host, null);
|
|
1290 |
return obj;
|
|
1291 |
}
|
|
1292 |
|
|
1293 |
// If the host is in the lookupTable, it means that another
|
|
1294 |
// thread is trying to look up the address of this host.
|
|
1295 |
// This thread should wait.
|
|
1296 |
while (lookupTable.containsKey(host)) {
|
|
1297 |
try {
|
|
1298 |
lookupTable.wait();
|
|
1299 |
} catch (InterruptedException e) {
|
|
1300 |
}
|
|
1301 |
}
|
|
1302 |
}
|
|
1303 |
|
|
1304 |
// The other thread has finished looking up the address of
|
|
1305 |
// the host. This thread should retry to get the address
|
|
1306 |
// from the addressCache. If it doesn't get the address from
|
|
1307 |
// the cache, it will try to look up the address itself.
|
|
1308 |
obj = getCachedAddress(host);
|
|
1309 |
if (obj == null) {
|
|
1310 |
synchronized (lookupTable) {
|
|
1311 |
lookupTable.put(host, null);
|
|
1312 |
}
|
|
1313 |
}
|
|
1314 |
|
|
1315 |
return obj;
|
|
1316 |
}
|
|
1317 |
|
|
1318 |
private static void updateLookupTable(String host) {
|
|
1319 |
synchronized (lookupTable) {
|
|
1320 |
lookupTable.remove(host);
|
|
1321 |
lookupTable.notifyAll();
|
|
1322 |
}
|
|
1323 |
}
|
|
1324 |
|
|
1325 |
/**
|
|
1326 |
* Returns an <code>InetAddress</code> object given the raw IP address .
|
|
1327 |
* The argument is in network byte order: the highest order
|
|
1328 |
* byte of the address is in <code>getAddress()[0]</code>.
|
|
1329 |
*
|
|
1330 |
* <p> This method doesn't block, i.e. no reverse name service lookup
|
|
1331 |
* is performed.
|
|
1332 |
*
|
|
1333 |
* <p> IPv4 address byte array must be 4 bytes long and IPv6 byte array
|
|
1334 |
* must be 16 bytes long
|
|
1335 |
*
|
|
1336 |
* @param addr the raw IP address in network byte order
|
|
1337 |
* @return an InetAddress object created from the raw IP address.
|
|
1338 |
* @exception UnknownHostException if IP address is of illegal length
|
|
1339 |
* @since 1.4
|
|
1340 |
*/
|
|
1341 |
public static InetAddress getByAddress(byte[] addr)
|
|
1342 |
throws UnknownHostException {
|
|
1343 |
return getByAddress(null, addr);
|
|
1344 |
}
|
|
1345 |
|
|
1346 |
private static InetAddress cachedLocalHost = null;
|
|
1347 |
private static long cacheTime = 0;
|
|
1348 |
private static final long maxCacheTime = 5000L;
|
|
1349 |
private static final Object cacheLock = new Object();
|
|
1350 |
|
|
1351 |
/**
|
|
1352 |
* Returns the address of the local host. This is achieved by retrieving
|
|
1353 |
* the name of the host from the system, then resolving that name into
|
|
1354 |
* an <code>InetAddress</code>.
|
|
1355 |
*
|
|
1356 |
* <P>Note: The resolved address may be cached for a short period of time.
|
|
1357 |
* </P>
|
|
1358 |
*
|
|
1359 |
* <p>If there is a security manager, its
|
|
1360 |
* <code>checkConnect</code> method is called
|
|
1361 |
* with the local host name and <code>-1</code>
|
|
1362 |
* as its arguments to see if the operation is allowed.
|
|
1363 |
* If the operation is not allowed, an InetAddress representing
|
|
1364 |
* the loopback address is returned.
|
|
1365 |
*
|
|
1366 |
* @return the address of the local host.
|
|
1367 |
*
|
|
1368 |
* @exception UnknownHostException if the local host name could not
|
|
1369 |
* be resolved into an address.
|
|
1370 |
*
|
|
1371 |
* @see SecurityManager#checkConnect
|
|
1372 |
* @see java.net.InetAddress#getByName(java.lang.String)
|
|
1373 |
*/
|
|
1374 |
public static InetAddress getLocalHost() throws UnknownHostException {
|
|
1375 |
|
|
1376 |
SecurityManager security = System.getSecurityManager();
|
|
1377 |
try {
|
|
1378 |
String local = impl.getLocalHostName();
|
|
1379 |
|
|
1380 |
if (security != null) {
|
|
1381 |
security.checkConnect(local, -1);
|
|
1382 |
}
|
|
1383 |
|
|
1384 |
if (local.equals("localhost")) {
|
|
1385 |
return impl.loopbackAddress();
|
|
1386 |
}
|
|
1387 |
|
|
1388 |
InetAddress ret = null;
|
|
1389 |
synchronized (cacheLock) {
|
|
1390 |
long now = System.currentTimeMillis();
|
|
1391 |
if (cachedLocalHost != null) {
|
|
1392 |
if ((now - cacheTime) < maxCacheTime) // Less than 5s old?
|
|
1393 |
ret = cachedLocalHost;
|
|
1394 |
else
|
|
1395 |
cachedLocalHost = null;
|
|
1396 |
}
|
|
1397 |
|
|
1398 |
// we are calling getAddressFromNameService directly
|
|
1399 |
// to avoid getting localHost from cache
|
|
1400 |
if (ret == null) {
|
|
1401 |
InetAddress[] localAddrs;
|
|
1402 |
try {
|
|
1403 |
localAddrs =
|
|
1404 |
(InetAddress[]) InetAddress.getAddressFromNameService(local);
|
|
1405 |
} catch (UnknownHostException uhe) {
|
|
1406 |
throw new UnknownHostException(local + ": " + uhe.getMessage());
|
|
1407 |
}
|
|
1408 |
cachedLocalHost = localAddrs[0];
|
|
1409 |
cacheTime = now;
|
|
1410 |
ret = localAddrs[0];
|
|
1411 |
}
|
|
1412 |
}
|
|
1413 |
return ret;
|
|
1414 |
} catch (java.lang.SecurityException e) {
|
|
1415 |
return impl.loopbackAddress();
|
|
1416 |
}
|
|
1417 |
}
|
|
1418 |
|
|
1419 |
/**
|
|
1420 |
* Perform class load-time initializations.
|
|
1421 |
*/
|
|
1422 |
private static native void init();
|
|
1423 |
|
|
1424 |
|
|
1425 |
/*
|
|
1426 |
* Returns the InetAddress representing anyLocalAddress
|
|
1427 |
* (typically 0.0.0.0 or ::0)
|
|
1428 |
*/
|
|
1429 |
static InetAddress anyLocalAddress() {
|
|
1430 |
return impl.anyLocalAddress();
|
|
1431 |
}
|
|
1432 |
|
|
1433 |
/*
|
|
1434 |
* Load and instantiate an underlying impl class
|
|
1435 |
*/
|
|
1436 |
static Object loadImpl(String implName) {
|
|
1437 |
Object impl;
|
|
1438 |
|
|
1439 |
/*
|
|
1440 |
* Property "impl.prefix" will be prepended to the classname
|
|
1441 |
* of the implementation object we instantiate, to which we
|
|
1442 |
* delegate the real work (like native methods). This
|
|
1443 |
* property can vary across implementations of the java.
|
|
1444 |
* classes. The default is an empty String "".
|
|
1445 |
*/
|
|
1446 |
String prefix = AccessController.doPrivileged(
|
|
1447 |
new GetPropertyAction("impl.prefix", ""));
|
|
1448 |
impl = null;
|
|
1449 |
try {
|
|
1450 |
impl = Class.forName("java.net." + prefix + implName).newInstance();
|
|
1451 |
} catch (ClassNotFoundException e) {
|
|
1452 |
System.err.println("Class not found: java.net." + prefix +
|
|
1453 |
implName + ":\ncheck impl.prefix property " +
|
|
1454 |
"in your properties file.");
|
|
1455 |
} catch (InstantiationException e) {
|
|
1456 |
System.err.println("Could not instantiate: java.net." + prefix +
|
|
1457 |
implName + ":\ncheck impl.prefix property " +
|
|
1458 |
"in your properties file.");
|
|
1459 |
} catch (IllegalAccessException e) {
|
|
1460 |
System.err.println("Cannot access class: java.net." + prefix +
|
|
1461 |
implName + ":\ncheck impl.prefix property " +
|
|
1462 |
"in your properties file.");
|
|
1463 |
}
|
|
1464 |
|
|
1465 |
if (impl == null) {
|
|
1466 |
try {
|
|
1467 |
impl = Class.forName(implName).newInstance();
|
|
1468 |
} catch (Exception e) {
|
|
1469 |
throw new Error("System property impl.prefix incorrect");
|
|
1470 |
}
|
|
1471 |
}
|
|
1472 |
|
|
1473 |
return impl;
|
|
1474 |
}
|
|
1475 |
}
|
|
1476 |
|
|
1477 |
/*
|
|
1478 |
* Simple factory to create the impl
|
|
1479 |
*/
|
|
1480 |
class InetAddressImplFactory {
|
|
1481 |
|
|
1482 |
static InetAddressImpl create() {
|
|
1483 |
Object o;
|
|
1484 |
if (isIPv6Supported()) {
|
|
1485 |
o = InetAddress.loadImpl("Inet6AddressImpl");
|
|
1486 |
} else {
|
|
1487 |
o = InetAddress.loadImpl("Inet4AddressImpl");
|
|
1488 |
}
|
|
1489 |
return (InetAddressImpl)o;
|
|
1490 |
}
|
|
1491 |
|
|
1492 |
static native boolean isIPv6Supported();
|
|
1493 |
}
|