001: /*
002: * @(#)Inet4Address.java 1.27 06/10/10
003: *
004: * Copyright 1990-2006 Sun Microsystems, Inc. All Rights Reserved.
005: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
006: *
007: * This program is free software; you can redistribute it and/or
008: * modify it under the terms of the GNU General Public License version
009: * 2 only, as published by the Free Software Foundation.
010: *
011: * This program is distributed in the hope that it will be useful, but
012: * WITHOUT ANY WARRANTY; without even the implied warranty of
013: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014: * General Public License version 2 for more details (a copy is
015: * included at /legal/license.txt).
016: *
017: * You should have received a copy of the GNU General Public License
018: * version 2 along with this work; if not, write to the Free Software
019: * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
020: * 02110-1301 USA
021: *
022: * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
023: * Clara, CA 95054 or visit www.sun.com if you need additional
024: * information or have any questions.
025: */
026:
027: package java.net;
028:
029: import java.security.AccessController;
030: import java.io.ObjectStreamException;
031: import sun.security.action.*;
032:
033: /**
034: * This class represents an Internet Protocol version 4 (IPv4) address.
035: * Defined by <a href="http://www.ietf.org/rfc/rfc790.txt">
036: * <i>RFC 790: Assigned Numbers</i></a>,
037: * <a href="http://www.ietf.org/rfc/rfc1918.txt">
038: * <i>RFC 1918: Address Allocation for Private Internets</i></a>,
039: * and <a href="http://www.ietf.org/rfc/rfc2365.txt"><i>RFC 2365:
040: * Administratively Scoped IP Multicast</i></a>
041: *
042: * <h4> <A NAME="format">Textual representation of IP addresses<a> </h4>
043: *
044: * Textual representation of IPv4 address used as input to methods
045: * takes one of the following forms:
046: *
047: * <blockquote><table cellpadding=0 cellspacing=0 summary="layout">
048: * <tr><td><tt>d.d.d.d</tt><td></tr>
049: * <tr><td><tt>d.d.d</tt><td></tr>
050: * <tr><td><tt>d.d</td></tr>
051: * <tr><td><tt>d</td></tr>
052: * </table></blockquote>
053: *
054: * <p> When four parts are specified, each is interpreted as a byte of
055: * data and assigned, from left to right, to the four bytes of an IPv4
056: * address.
057:
058: * <p> When a three part address is specified, the last part is
059: * interpreted as a 16-bit quantity and placed in the right most two
060: * bytes of the network address. This makes the three part address
061: * format convenient for specifying Class B net- work addresses as
062: * 128.net.host.
063: *
064: * <p> When a two part address is supplied, the last part is
065: * interpreted as a 24-bit quantity and placed in the right most three
066: * bytes of the network address. This makes the two part address
067: * format convenient for specifying Class A network addresses as
068: * net.host.
069: *
070: * <p> When only one part is given, the value is stored directly in
071: * the network address without any byte rearrangement.
072: *
073: * <p> For methods that return a textual representation as output
074: * value, the first form, i.e. a dotted-quad string, is used.
075: *
076: * <h4> The Scope of a Multicast Address </h4>
077: *
078: * Historically the IPv4 TTL field in the IP header has doubled as a
079: * multicast scope field: a TTL of 0 means node-local, 1 means
080: * link-local, up through 32 means site-local, up through 64 means
081: * region-local, up through 128 means continent-local, and up through
082: * 255 are global. However, the administrative scoping is preferred.
083: * Please refer to <a href="http://www.ietf.org/rfc/rfc2365.txt">
084: * <i>RFC 2365: Administratively Scoped IP Multicast</i></a>
085: */
086:
087: public final class Inet4Address extends InetAddress {
088: final static int INADDRSZ = 4;
089:
090: /** use serialVersionUID from InetAddress, but Inet4Address instance
091: * is always replaced by an InetAddress instance before being
092: * serialized */
093: private static final long serialVersionUID = 3286316764910316507L;
094:
095: /*
096: * Perform initializations.
097: */
098: static {
099: init();
100: }
101:
102: Inet4Address() {
103: super ();
104: hostName = null;
105: address = 0;
106: family = IPv4;
107: }
108:
109: Inet4Address(String hostName, byte addr[]) {
110: this .hostName = hostName;
111: this .family = IPv4;
112: if (addr != null) {
113: if (addr.length == INADDRSZ) {
114: address = addr[3] & 0xFF;
115: address |= ((addr[2] << 8) & 0xFF00);
116: address |= ((addr[1] << 16) & 0xFF0000);
117: address |= ((addr[0] << 24) & 0xFF000000);
118: }
119: }
120: }
121:
122: Inet4Address(String hostName, int address) {
123: this .hostName = hostName;
124: this .family = IPv4;
125: this .address = address;
126: }
127:
128: /**
129: * Replaces the object to be serialized with an InetAddress object.
130: *
131: * @return the alternate object to be serialized.
132: *
133: * @throws ObjectStreamException if a new object replacing this
134: * object could not be created
135: */
136: private Object writeReplace() throws ObjectStreamException {
137: // will replace the to be serialized 'this' object
138: InetAddress inet = new InetAddress();
139: inet.hostName = this .hostName;
140: inet.address = this .address;
141:
142: /**
143: * Prior to 1.4 an InetAddress was created with a family
144: * based on the platform AF_INET value (usually 2).
145: * For compatibility reasons we must therefore write the
146: * the InetAddress with this family.
147: */
148: inet.family = 2;
149:
150: return inet;
151: }
152:
153: /**
154: * Utility routine to check if the InetAddress is an
155: * IP multicast address. IP multicast address is a Class D
156: * address i.e first four bits of the address are 1110.
157: * @return a <code>boolean</code> indicating if the InetAddress is
158: * an IP multicast address
159: * @since JDK1.1
160: */
161: public boolean isMulticastAddress() {
162: return ((address & 0xf0000000) == 0xe0000000);
163: }
164:
165: /**
166: * Utility routine to check if the InetAddress in a wildcard address.
167: * @return a <code>boolean</code> indicating if the Inetaddress is
168: * a wildcard address.
169: * @since 1.4
170: */
171: public boolean isAnyLocalAddress() {
172: return address == 0;
173: }
174:
175: /**
176: * Utility routine to check if the InetAddress is a loopback address.
177: *
178: * @return a <code>boolean</code> indicating if the InetAddress is
179: * a loopback address; or false otherwise.
180: * @since 1.4
181: */
182: private static final int loopback = 2130706433; /* 127.0.0.1 */
183:
184: public boolean isLoopbackAddress() {
185: /* 127.x.x.x */
186: byte[] byteAddr = getAddress();
187: return byteAddr[0] == 127;
188: }
189:
190: /**
191: * Utility routine to check if the InetAddress is an link local address.
192: *
193: * @return a <code>boolean</code> indicating if the InetAddress is
194: * a link local address; or false if address is not a link local unicast address.
195: * @since 1.4
196: */
197: public boolean isLinkLocalAddress() {
198: // link-local unicast in IPv4 (169.254.0.0/16)
199: // defined in "Documenting Special Use IPv4 Address Blocks
200: // that have been Registered with IANA" by Bill Manning
201: // draft-manning-dsua-06.txt
202: return (((address >>> 24) & 0xFF) == 169)
203: && (((address >>> 16) & 0xFF) == 254);
204: }
205:
206: /**
207: * Utility routine to check if the InetAddress is a site local address.
208: *
209: * @return a <code>boolean</code> indicating if the InetAddress is
210: * a site local address; or false if address is not a site local unicast address.
211: * @since 1.4
212: */
213: public boolean isSiteLocalAddress() {
214: // refer to RFC 1918
215: // 10/8 prefix
216: // 172.16/12 prefix
217: // 192.168/16 prefix
218: return (((address >>> 24) & 0xFF) == 10)
219: || ((((address >>> 24) & 0xFF) == 172) && (((address >>> 16) & 0xF0) == 16))
220: || ((((address >>> 24) & 0xFF) == 192) && (((address >>> 16) & 0xFF) == 168));
221: }
222:
223: /**
224: * Utility routine to check if the multicast address has global scope.
225: *
226: * @return a <code>boolean</code> indicating if the address has
227: * is a multicast address of global scope, false if it is not
228: * of global scope or it is not a multicast address
229: * @since 1.4
230: */
231: public boolean isMCGlobal() {
232: // 224.0.1.0 to 238.255.255.255
233: byte[] byteAddr = getAddress();
234: return ((byteAddr[0] & 0xff) >= 224 && (byteAddr[0] & 0xff) <= 238)
235: && !((byteAddr[0] & 0xff) == 224 && byteAddr[1] == 0 && byteAddr[2] == 0);
236: }
237:
238: /**
239: * Utility routine to check if the multicast address has node scope.
240: *
241: * @return a <code>boolean</code> indicating if the address has
242: * is a multicast address of node-local scope, false if it is not
243: * of node-local scope or it is not a multicast address
244: * @since 1.4
245: */
246: public boolean isMCNodeLocal() {
247: // unless ttl == 0
248: return false;
249: }
250:
251: /**
252: * Utility routine to check if the multicast address has link scope.
253: *
254: * @return a <code>boolean</code> indicating if the address has
255: * is a multicast address of link-local scope, false if it is not
256: * of link-local scope or it is not a multicast address
257: * @since 1.4
258: */
259: public boolean isMCLinkLocal() {
260: // 224.0.0/24 prefix and ttl == 1
261: return (((address >>> 24) & 0xFF) == 224)
262: && (((address >>> 16) & 0xFF) == 0)
263: && (((address >>> 8) & 0xFF) == 0);
264: }
265:
266: /**
267: * Utility routine to check if the multicast address has site scope.
268: *
269: * @return a <code>boolean</code> indicating if the address has
270: * is a multicast address of site-local scope, false if it is not
271: * of site-local scope or it is not a multicast address
272: * @since 1.4
273: */
274: public boolean isMCSiteLocal() {
275: // 239.255/16 prefix or ttl < 32
276: return (((address >>> 24) & 0xFF) == 239)
277: && (((address >>> 16) & 0xFF) == 255);
278: }
279:
280: /**
281: * Utility routine to check if the multicast address has organization scope.
282: *
283: * @return a <code>boolean</code> indicating if the address has
284: * is a multicast address of organization-local scope,
285: * false if it is not of organization-local scope
286: * or it is not a multicast address
287: * @since 1.4
288: */
289: public boolean isMCOrgLocal() {
290: // 239.192 - 239.195
291: return (((address >>> 24) & 0xFF) == 239)
292: && (((address >>> 16) & 0xFF) >= 192)
293: && (((address >>> 16) & 0xFF) <= 195);
294: }
295:
296: /**
297: * Returns the raw IP address of this <code>InetAddress</code>
298: * object. The result is in network byte order: the highest order
299: * byte of the address is in <code>getAddress()[0]</code>.
300: *
301: * @return the raw IP address of this object.
302: */
303: public byte[] getAddress() {
304: byte[] addr = new byte[INADDRSZ];
305:
306: addr[0] = (byte) ((address >>> 24) & 0xFF);
307: addr[1] = (byte) ((address >>> 16) & 0xFF);
308: addr[2] = (byte) ((address >>> 8) & 0xFF);
309: addr[3] = (byte) (address & 0xFF);
310: return addr;
311: }
312:
313: /**
314: * Returns the IP address string in textual presentation form.
315: *
316: * @return the raw IP address in a string format.
317: * @since JDK1.0.2
318: */
319: public String getHostAddress() {
320: return numericToTextFormat(getAddress());
321: }
322:
323: /**
324: * Returns a hashcode for this IP address.
325: *
326: * @return a hash code value for this IP address.
327: */
328: public int hashCode() {
329: return address;
330: }
331:
332: /**
333: * Compares this object against the specified object.
334: * The result is <code>true</code> if and only if the argument is
335: * not <code>null</code> and it represents the same IP address as
336: * this object.
337: * <p>
338: * Two instances of <code>InetAddress</code> represent the same IP
339: * address if the length of the byte arrays returned by
340: * <code>getAddress</code> is the same for both, and each of the
341: * array components is the same for the byte arrays.
342: *
343: * @param obj the object to compare against.
344: * @return <code>true</code> if the objects are the same;
345: * <code>false</code> otherwise.
346: * @see java.net.InetAddress#getAddress()
347: */
348: public boolean equals(Object obj) {
349: return (obj != null) && (obj instanceof Inet4Address)
350: && (((InetAddress) obj).address == address);
351: }
352:
353: // Utilities
354: /*
355: * Converts IPv4 binary address into a string suitable for presentation.
356: *
357: * @param src a byte array representing an IPv4 numeric address
358: * @return a String representing the IPv4 address in
359: * textual representation format
360: * @since 1.4
361: */
362:
363: static String numericToTextFormat(byte[] src) {
364: return (src[0] & 0xff) + "." + (src[1] & 0xff) + "."
365: + (src[2] & 0xff) + "." + (src[3] & 0xff);
366: }
367:
368: /*
369: * Converts IPv4 address in its textual presentation form
370: * into its numeric binary form.
371: *
372: * @param src a String representing an IPv4 address in standard format
373: * @return a byte array representing the IPv4 numeric address
374: * @since 1.4
375: */
376: static byte[] textToNumericFormat(String src) {
377: if (src.length() == 0) {
378: return null;
379: }
380:
381: int octets;
382: char ch;
383: byte[] dst = new byte[INADDRSZ];
384: char[] srcb = src.toCharArray();
385: boolean saw_digit = false;
386:
387: octets = 0;
388: int i = 0;
389: int cur = 0;
390: while (i < srcb.length) {
391: ch = srcb[i++];
392: if (Character.isDigit(ch)) {
393: // note that Java byte is signed, so need to convert to int
394: int sum = (dst[cur] & 0xff) * 10
395: + (Character.digit(ch, 10) & 0xff);
396:
397: if (sum > 255)
398: return null;
399:
400: dst[cur] = (byte) (sum & 0xff);
401: if (!saw_digit) {
402: if (++octets > INADDRSZ)
403: return null;
404: saw_digit = true;
405: }
406: } else if (ch == '.' && saw_digit) {
407: if (octets == INADDRSZ)
408: return null;
409: cur++;
410: dst[cur] = 0;
411: saw_digit = false;
412: } else
413: return null;
414: }
415: if (octets < INADDRSZ)
416: return null;
417: return dst;
418: }
419:
420: /**
421: * Perform class load-time initializations.
422: */
423: private static native void init();
424: }
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