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1 /*
2  * Copyright (C) 2014 The Android Open Source Project
3  * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5  *
6  * This code is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 only, as
8  * published by the Free Software Foundation.  Oracle designates this
9  * particular file as subject to the "Classpath" exception as provided
10  * by Oracle in the LICENSE file that accompanied this code.
11  *
12  * This code is distributed in the hope that it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15  * version 2 for more details (a copy is included in the LICENSE file that
16  * accompanied this code).
17  *
18  * You should have received a copy of the GNU General Public License version
19  * 2 along with this work; if not, write to the Free Software Foundation,
20  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21  *
22  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
23  * or visit www.oracle.com if you need additional information or have any
24  * questions.
25  */
26 
27 package java.net;
28 
29 import java.io.ObjectStreamException;
30 import static android.system.OsConstants.*;
31 
32 /**
33  * This class represents an Internet Protocol version 4 (IPv4) address.
34  * Defined by <a href="http://www.ietf.org/rfc/rfc790.txt">
35  * <i>RFC&nbsp;790: Assigned Numbers</i></a>,
36  * <a href="http://www.ietf.org/rfc/rfc1918.txt">
37  * <i>RFC&nbsp;1918: Address Allocation for Private Internets</i></a>,
38  * and <a href="http://www.ietf.org/rfc/rfc2365.txt"><i>RFC&nbsp;2365:
39  * Administratively Scoped IP Multicast</i></a>
40  *
41  * <h3> <A NAME="format">Textual representation of IP addresses</a> </h3>
42  *
43  * Textual representation of IPv4 address used as input to methods
44  * takes one of the following forms:
45  *
46  * <blockquote><table cellpadding=0 cellspacing=0 summary="layout">
47  * <tr><td>{@code d.d.d.d}</td></tr>
48  * <tr><td>{@code d.d.d}</td></tr>
49  * <tr><td>{@code d.d}</td></tr>
50  * <tr><td>{@code d}</td></tr>
51  * </table></blockquote>
52  *
53  * <p> When four parts are specified, each is interpreted as a byte of
54  * data and assigned, from left to right, to the four bytes of an IPv4
55  * address.
56 
57  * <p> When a three part address is specified, the last part is
58  * interpreted as a 16-bit quantity and placed in the right most two
59  * bytes of the network address. This makes the three part address
60  * format convenient for specifying Class B net- work addresses as
61  * 128.net.host.
62  *
63  * <p> When a two part address is supplied, the last part is
64  * interpreted as a 24-bit quantity and placed in the right most three
65  * bytes of the network address. This makes the two part address
66  * format convenient for specifying Class A network addresses as
67  * net.host.
68  *
69  * <p> When only one part is given, the value is stored directly in
70  * the network address without any byte rearrangement.
71  *
72  * <p> For methods that return a textual representation as output
73  * value, the first form, i.e. a dotted-quad string, is used.
74  *
75  * <h4> The Scope of a Multicast Address </h4>
76  *
77  * Historically the IPv4 TTL field in the IP header has doubled as a
78  * multicast scope field: a TTL of 0 means node-local, 1 means
79  * link-local, up through 32 means site-local, up through 64 means
80  * region-local, up through 128 means continent-local, and up through
81  * 255 are global. However, the administrative scoping is preferred.
82  * Please refer to <a href="http://www.ietf.org/rfc/rfc2365.txt">
83  * <i>RFC&nbsp;2365: Administratively Scoped IP Multicast</i></a>
84  * @since 1.4
85  */
86 
87 public final
88 class Inet4Address extends InetAddress {
89     final static int INADDRSZ = 4;
90 
91     /** use serialVersionUID from InetAddress, but Inet4Address instance
92      *  is always replaced by an InetAddress instance before being
93      *  serialized */
94     private static final long serialVersionUID = 3286316764910316507L;
95 
96     // BEGIN Android-added: Define special-purpose IPv4 address
97     /** @hide */
98     public static final InetAddress ANY = new Inet4Address(null, new byte[] { 0, 0, 0, 0 });
99 
100     /** @hide */
101     public static final InetAddress ALL =
102             new Inet4Address(null, new byte[] { (byte) 255, (byte) 255,
103                   (byte) 255, (byte) 255 });
104     /** @hide */
105     public static final InetAddress LOOPBACK =
106             new Inet4Address("localhost", new byte[] { 127, 0, 0, 1 });
107     // END Android-added: Define special-purpose IPv4 address
108 
109 
110     // BEGIN Android-removed: Android doesn't need to call native init
111     /*
112      * Perform initializations.
113      *
114     static {
115         init();
116     }
117     */
118     // END Android-removed: Android doesn't need to call native init
Inet4Address()119     Inet4Address() {
120         super();
121         holder().hostName = null;
122         holder().address = 0;
123         holder().family = AF_INET;
124     }
125 
Inet4Address(String hostName, byte addr[])126     Inet4Address(String hostName, byte addr[]) {
127         holder().hostName = hostName;
128         holder().family = AF_INET;
129         if (addr != null) {
130             if (addr.length == INADDRSZ) {
131                 int address  = addr[3] & 0xFF;
132                 address |= ((addr[2] << 8) & 0xFF00);
133                 address |= ((addr[1] << 16) & 0xFF0000);
134                 address |= ((addr[0] << 24) & 0xFF000000);
135                 holder().address = address;
136             }
137         }
138         holder().originalHostName = hostName;
139     }
Inet4Address(String hostName, int address)140     Inet4Address(String hostName, int address) {
141         holder().hostName = hostName;
142         holder().family = AF_INET;
143         holder().address = address;
144         holder().originalHostName = hostName;
145     }
146 
147     /**
148      * Replaces the object to be serialized with an InetAddress object.
149      *
150      * @return the alternate object to be serialized.
151      *
152      * @throws ObjectStreamException if a new object replacing this
153      * object could not be created
154      */
writeReplace()155     private Object writeReplace() throws ObjectStreamException {
156         // will replace the to be serialized 'this' object
157         InetAddress inet = new InetAddress();
158         inet.holder().hostName = holder().getHostName();
159         inet.holder().address = holder().getAddress();
160 
161         /**
162          * Prior to 1.4 an InetAddress was created with a family
163          * based on the platform AF_INET value (usually 2).
164          * For compatibility reasons we must therefore write the
165          * the InetAddress with this family.
166          */
167         inet.holder().family = 2;
168 
169         return inet;
170     }
171 
172     /**
173      * Utility routine to check if the InetAddress is an
174      * IP multicast address. IP multicast address is a Class D
175      * address i.e first four bits of the address are 1110.
176      * @return a {@code boolean} indicating if the InetAddress is
177      * an IP multicast address
178      * @since   JDK1.1
179      */
isMulticastAddress()180     public boolean isMulticastAddress() {
181         return ((holder().getAddress() & 0xf0000000) == 0xe0000000);
182     }
183 
184     /**
185      * Utility routine to check if the InetAddress in a wildcard address.
186      * @return a {@code boolean} indicating if the Inetaddress is
187      *         a wildcard address.
188      * @since 1.4
189      */
isAnyLocalAddress()190     public boolean isAnyLocalAddress() {
191         return holder().getAddress() == 0;
192     }
193 
194     /**
195      * Utility routine to check if the InetAddress is a loopback address.
196      *
197      * @return a {@code boolean} indicating if the InetAddress is
198      * a loopback address; or false otherwise.
199      * @since 1.4
200      */
isLoopbackAddress()201     public boolean isLoopbackAddress() {
202         /* 127.x.x.x */
203         byte[] byteAddr = getAddress();
204         return byteAddr[0] == 127;
205     }
206 
207     /**
208      * Utility routine to check if the InetAddress is an link local address.
209      *
210      * @return a {@code boolean} indicating if the InetAddress is
211      * a link local address; or false if address is not a link local unicast address.
212      * @since 1.4
213      */
isLinkLocalAddress()214     public boolean isLinkLocalAddress() {
215         // link-local unicast in IPv4 (169.254.0.0/16)
216         // defined in "Documenting Special Use IPv4 Address Blocks
217         // that have been Registered with IANA" by Bill Manning
218         // draft-manning-dsua-06.txt
219         int address = holder().getAddress();
220         return (((address >>> 24) & 0xFF) == 169)
221             && (((address >>> 16) & 0xFF) == 254);
222     }
223 
224     /**
225      * Utility routine to check if the InetAddress is a site local address.
226      *
227      * @return a {@code boolean} indicating if the InetAddress is
228      * a site local address; or false if address is not a site local unicast address.
229      * @since 1.4
230      */
isSiteLocalAddress()231     public boolean isSiteLocalAddress() {
232         // refer to RFC 1918
233         // 10/8 prefix
234         // 172.16/12 prefix
235         // 192.168/16 prefix
236         int address = holder().getAddress();
237         return (((address >>> 24) & 0xFF) == 10)
238             || ((((address >>> 24) & 0xFF) == 172)
239                 && (((address >>> 16) & 0xF0) == 16))
240             || ((((address >>> 24) & 0xFF) == 192)
241                 && (((address >>> 16) & 0xFF) == 168));
242     }
243 
244     /**
245      * Utility routine to check if the multicast address has global scope.
246      *
247      * @return a {@code boolean} indicating if the address has
248      *         is a multicast address of global scope, false if it is not
249      *         of global scope or it is not a multicast address
250      * @since 1.4
251      */
isMCGlobal()252     public boolean isMCGlobal() {
253         // 224.0.1.0 to 238.255.255.255
254         byte[] byteAddr = getAddress();
255         return ((byteAddr[0] & 0xff) >= 224 && (byteAddr[0] & 0xff) <= 238 ) &&
256             !((byteAddr[0] & 0xff) == 224 && byteAddr[1] == 0 &&
257               byteAddr[2] == 0);
258     }
259 
260     /**
261      * Utility routine to check if the multicast address has node scope.
262      *
263      * @return a {@code boolean} indicating if the address has
264      *         is a multicast address of node-local scope, false if it is not
265      *         of node-local scope or it is not a multicast address
266      * @since 1.4
267      */
isMCNodeLocal()268     public boolean isMCNodeLocal() {
269         // unless ttl == 0
270         return false;
271     }
272 
273     /**
274      * Utility routine to check if the multicast address has link scope.
275      *
276      * @return a {@code boolean} indicating if the address has
277      *         is a multicast address of link-local scope, false if it is not
278      *         of link-local scope or it is not a multicast address
279      * @since 1.4
280      */
isMCLinkLocal()281     public boolean isMCLinkLocal() {
282         // 224.0.0/24 prefix and ttl == 1
283         int address = holder().getAddress();
284         return (((address >>> 24) & 0xFF) == 224)
285             && (((address >>> 16) & 0xFF) == 0)
286             && (((address >>> 8) & 0xFF) == 0);
287     }
288 
289     /**
290      * Utility routine to check if the multicast address has site scope.
291      *
292      * @return a {@code boolean} indicating if the address has
293      *         is a multicast address of site-local scope, false if it is not
294      *         of site-local scope or it is not a multicast address
295      * @since 1.4
296      */
isMCSiteLocal()297     public boolean isMCSiteLocal() {
298         // 239.255/16 prefix or ttl < 32
299         int address = holder().getAddress();
300         return (((address >>> 24) & 0xFF) == 239)
301             && (((address >>> 16) & 0xFF) == 255);
302     }
303 
304     /**
305      * Utility routine to check if the multicast address has organization scope.
306      *
307      * @return a {@code boolean} indicating if the address has
308      *         is a multicast address of organization-local scope,
309      *         false if it is not of organization-local scope
310      *         or it is not a multicast address
311      * @since 1.4
312      */
isMCOrgLocal()313     public boolean isMCOrgLocal() {
314         // 239.192 - 239.195
315         int address = holder().getAddress();
316         return (((address >>> 24) & 0xFF) == 239)
317             && (((address >>> 16) & 0xFF) >= 192)
318             && (((address >>> 16) & 0xFF) <= 195);
319     }
320 
321     /**
322      * Returns the raw IP address of this {@code InetAddress}
323      * object. The result is in network byte order: the highest order
324      * byte of the address is in {@code getAddress()[0]}.
325      *
326      * @return  the raw IP address of this object.
327      */
getAddress()328     public byte[] getAddress() {
329         int address = holder().getAddress();
330         byte[] addr = new byte[INADDRSZ];
331 
332         addr[0] = (byte) ((address >>> 24) & 0xFF);
333         addr[1] = (byte) ((address >>> 16) & 0xFF);
334         addr[2] = (byte) ((address >>> 8) & 0xFF);
335         addr[3] = (byte) (address & 0xFF);
336         return addr;
337     }
338 
339     /**
340      * Returns the IP address string in textual presentation form.
341      *
342      * @return  the raw IP address in a string format.
343      * @since   JDK1.0.2
344      */
getHostAddress()345     public String getHostAddress() {
346         return numericToTextFormat(getAddress());
347     }
348 
349     /**
350      * Returns a hashcode for this IP address.
351      *
352      * @return  a hash code value for this IP address.
353      */
hashCode()354     public int hashCode() {
355         return holder().getAddress();
356     }
357 
358     /**
359      * Compares this object against the specified object.
360      * The result is {@code true} if and only if the argument is
361      * not {@code null} and it represents the same IP address as
362      * this object.
363      * <p>
364      * Two instances of {@code InetAddress} represent the same IP
365      * address if the length of the byte arrays returned by
366      * {@code getAddress} is the same for both, and each of the
367      * array components is the same for the byte arrays.
368      *
369      * @param   obj   the object to compare against.
370      * @return  {@code true} if the objects are the same;
371      *          {@code false} otherwise.
372      * @see     java.net.InetAddress#getAddress()
373      */
equals(Object obj)374     public boolean equals(Object obj) {
375         return (obj != null) && (obj instanceof Inet4Address) &&
376             (((InetAddress)obj).holder().getAddress() == holder().getAddress());
377     }
378 
379     // Utilities
380     /*
381      * Converts IPv4 binary address into a string suitable for presentation.
382      *
383      * @param src a byte array representing an IPv4 numeric address
384      * @return a String representing the IPv4 address in
385      *         textual representation format
386      * @since 1.4
387      */
388 
numericToTextFormat(byte[] src)389     static String numericToTextFormat(byte[] src)
390     {
391         return (src[0] & 0xff) + "." + (src[1] & 0xff) + "." + (src[2] & 0xff) + "." + (src[3] & 0xff);
392     }
393 
394     // BEGIN Android-removed: Android doesn't need to call native init
395     /*
396      * Perform class load-time initializations.
397      *
398     private static native void init();
399     */
400     // END Android-removed: Android doesn't need to call native init
401 }
402