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