1 /* 2 * Copyright (C) 2014 The Android Open Source Project 3 * Copyright (c) 2000, 2006, 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.security.AccessController; 30 import java.io.ObjectStreamException; 31 import sun.security.action.*; 32 import static android.system.OsConstants.*; 33 34 /** 35 * This class represents an Internet Protocol version 4 (IPv4) address. 36 * Defined by <a href="http://www.ietf.org/rfc/rfc790.txt"> 37 * <i>RFC 790: Assigned Numbers</i></a>, 38 * <a href="http://www.ietf.org/rfc/rfc1918.txt"> 39 * <i>RFC 1918: Address Allocation for Private Internets</i></a>, 40 * and <a href="http://www.ietf.org/rfc/rfc2365.txt"><i>RFC 2365: 41 * Administratively Scoped IP Multicast</i></a> 42 * 43 * <h4> <A NAME="format">Textual representation of IP addresses</a> </h4> 44 * 45 * Textual representation of IPv4 address used as input to methods 46 * takes one of the following forms: 47 * 48 * <blockquote><table cellpadding=0 cellspacing=0 summary="layout"> 49 * <tr><td><tt>d.d.d.d</tt></td></tr> 50 * <tr><td><tt>d.d.d</tt></td></tr> 51 * <tr><td><tt>d.d</tt></td></tr> 52 * <tr><td><tt>d</tt></td></tr> 53 * </table></blockquote> 54 * 55 * <p> When four parts are specified, each is interpreted as a byte of 56 * data and assigned, from left to right, to the four bytes of an IPv4 57 * address. 58 59 * <p> When a three part address is specified, the last part is 60 * interpreted as a 16-bit quantity and placed in the right most two 61 * bytes of the network address. This makes the three part address 62 * format convenient for specifying Class B net- work addresses as 63 * 128.net.host. 64 * 65 * <p> When a two part address is supplied, the last part is 66 * interpreted as a 24-bit quantity and placed in the right most three 67 * bytes of the network address. This makes the two part address 68 * format convenient for specifying Class A network addresses as 69 * net.host. 70 * 71 * <p> When only one part is given, the value is stored directly in 72 * the network address without any byte rearrangement. 73 * 74 * <p> For methods that return a textual representation as output 75 * value, the first form, i.e. a dotted-quad string, is used. 76 * 77 * <h4> The Scope of a Multicast Address </h4> 78 * 79 * Historically the IPv4 TTL field in the IP header has doubled as a 80 * multicast scope field: a TTL of 0 means node-local, 1 means 81 * link-local, up through 32 means site-local, up through 64 means 82 * region-local, up through 128 means continent-local, and up through 83 * 255 are global. However, the administrative scoping is preferred. 84 * Please refer to <a href="http://www.ietf.org/rfc/rfc2365.txt"> 85 * <i>RFC 2365: Administratively Scoped IP Multicast</i></a> 86 * @since 1.4 87 */ 88 89 public final 90 class Inet4Address extends InetAddress { 91 final static int INADDRSZ = 4; 92 93 /** use serialVersionUID from InetAddress, but Inet4Address instance 94 * is always replaced by an InetAddress instance before being 95 * serialized */ 96 private static final long serialVersionUID = 3286316764910316507L; 97 98 /** @hide */ 99 public static final InetAddress ANY = new Inet4Address(null, new byte[] { 0, 0, 0, 0 }); 100 101 /** @hide */ 102 public static final InetAddress ALL = 103 new Inet4Address(null, new byte[] { (byte) 255, (byte) 255, 104 (byte) 255, (byte) 255 }); 105 /** @hide */ 106 public static final InetAddress LOOPBACK = 107 new Inet4Address("localhost", new byte[] { 127, 0, 0, 1 }); 108 Inet4Address()109 Inet4Address() { 110 super(); 111 holder().hostName = null; 112 holder().address = 0; 113 holder().family = AF_INET; 114 } 115 Inet4Address(String hostName, byte addr[])116 Inet4Address(String hostName, byte addr[]) { 117 holder().hostName = hostName; 118 holder().family = AF_INET; 119 if (addr != null) { 120 if (addr.length == INADDRSZ) { 121 int address = addr[3] & 0xFF; 122 address |= ((addr[2] << 8) & 0xFF00); 123 address |= ((addr[1] << 16) & 0xFF0000); 124 address |= ((addr[0] << 24) & 0xFF000000); 125 holder().address = address; 126 } 127 } 128 } Inet4Address(String hostName, int address)129 Inet4Address(String hostName, int address) { 130 holder().hostName = hostName; 131 holder().family = AF_INET; 132 holder().address = address; 133 } 134 135 /** 136 * Replaces the object to be serialized with an InetAddress object. 137 * 138 * @return the alternate object to be serialized. 139 * 140 * @throws ObjectStreamException if a new object replacing this 141 * object could not be created 142 */ writeReplace()143 private Object writeReplace() throws ObjectStreamException { 144 // will replace the to be serialized 'this' object 145 InetAddress inet = new InetAddress(); 146 inet.holder().hostName = holder().getHostName(); 147 inet.holder().address = holder().getAddress(); 148 149 /** 150 * Prior to 1.4 an InetAddress was created with a family 151 * based on the platform AF_INET value (usually 2). 152 * For compatibility reasons we must therefore write the 153 * the InetAddress with this family. 154 */ 155 inet.holder().family = 2; 156 157 return inet; 158 } 159 160 /** 161 * Utility routine to check if the InetAddress is an 162 * IP multicast address. IP multicast address is a Class D 163 * address i.e first four bits of the address are 1110. 164 * @return a <code>boolean</code> indicating if the InetAddress is 165 * an IP multicast address 166 * @since JDK1.1 167 */ isMulticastAddress()168 public boolean isMulticastAddress() { 169 return ((holder().getAddress() & 0xf0000000) == 0xe0000000); 170 } 171 172 /** 173 * Utility routine to check if the InetAddress in a wildcard address. 174 * @return a <code>boolean</code> indicating if the Inetaddress is 175 * a wildcard address. 176 * @since 1.4 177 */ isAnyLocalAddress()178 public boolean isAnyLocalAddress() { 179 return holder().getAddress() == 0; 180 } 181 182 /** 183 * Utility routine to check if the InetAddress is a loopback address. 184 * 185 * @return a <code>boolean</code> indicating if the InetAddress is 186 * a loopback address; or false otherwise. 187 * @since 1.4 188 */ 189 private static final int loopback = 2130706433; /* 127.0.0.1 */ isLoopbackAddress()190 public boolean isLoopbackAddress() { 191 /* 127.x.x.x */ 192 byte[] byteAddr = getAddress(); 193 return byteAddr[0] == 127; 194 } 195 196 /** 197 * Utility routine to check if the InetAddress is an link local address. 198 * 199 * @return a <code>boolean</code> indicating if the InetAddress is 200 * a link local address; or false if address is not a link local unicast address. 201 * @since 1.4 202 */ isLinkLocalAddress()203 public boolean isLinkLocalAddress() { 204 // link-local unicast in IPv4 (169.254.0.0/16) 205 // defined in "Documenting Special Use IPv4 Address Blocks 206 // that have been Registered with IANA" by Bill Manning 207 // draft-manning-dsua-06.txt 208 int address = holder().getAddress(); 209 return (((address >>> 24) & 0xFF) == 169) 210 && (((address >>> 16) & 0xFF) == 254); 211 } 212 213 /** 214 * Utility routine to check if the InetAddress is a site local address. 215 * 216 * @return a <code>boolean</code> indicating if the InetAddress is 217 * a site local address; or false if address is not a site local unicast address. 218 * @since 1.4 219 */ isSiteLocalAddress()220 public boolean isSiteLocalAddress() { 221 // refer to RFC 1918 222 // 10/8 prefix 223 // 172.16/12 prefix 224 // 192.168/16 prefix 225 int address = holder().getAddress(); 226 return (((address >>> 24) & 0xFF) == 10) 227 || ((((address >>> 24) & 0xFF) == 172) 228 && (((address >>> 16) & 0xF0) == 16)) 229 || ((((address >>> 24) & 0xFF) == 192) 230 && (((address >>> 16) & 0xFF) == 168)); 231 } 232 233 /** 234 * Utility routine to check if the multicast address has global scope. 235 * 236 * @return a <code>boolean</code> indicating if the address has 237 * is a multicast address of global scope, false if it is not 238 * of global scope or it is not a multicast address 239 * @since 1.4 240 */ isMCGlobal()241 public boolean isMCGlobal() { 242 // 224.0.1.0 to 238.255.255.255 243 byte[] byteAddr = getAddress(); 244 return ((byteAddr[0] & 0xff) >= 224 && (byteAddr[0] & 0xff) <= 238 ) && 245 !((byteAddr[0] & 0xff) == 224 && byteAddr[1] == 0 && 246 byteAddr[2] == 0); 247 } 248 249 /** 250 * Utility routine to check if the multicast address has node scope. 251 * 252 * @return a <code>boolean</code> indicating if the address has 253 * is a multicast address of node-local scope, false if it is not 254 * of node-local scope or it is not a multicast address 255 * @since 1.4 256 */ isMCNodeLocal()257 public boolean isMCNodeLocal() { 258 // unless ttl == 0 259 return false; 260 } 261 262 /** 263 * Utility routine to check if the multicast address has link scope. 264 * 265 * @return a <code>boolean</code> indicating if the address has 266 * is a multicast address of link-local scope, false if it is not 267 * of link-local scope or it is not a multicast address 268 * @since 1.4 269 */ isMCLinkLocal()270 public boolean isMCLinkLocal() { 271 // 224.0.0/24 prefix and ttl == 1 272 int address = holder().getAddress(); 273 return (((address >>> 24) & 0xFF) == 224) 274 && (((address >>> 16) & 0xFF) == 0) 275 && (((address >>> 8) & 0xFF) == 0); 276 } 277 278 /** 279 * Utility routine to check if the multicast address has site scope. 280 * 281 * @return a <code>boolean</code> indicating if the address has 282 * is a multicast address of site-local scope, false if it is not 283 * of site-local scope or it is not a multicast address 284 * @since 1.4 285 */ isMCSiteLocal()286 public boolean isMCSiteLocal() { 287 // 239.255/16 prefix or ttl < 32 288 int address = holder().getAddress(); 289 return (((address >>> 24) & 0xFF) == 239) 290 && (((address >>> 16) & 0xFF) == 255); 291 } 292 293 /** 294 * Utility routine to check if the multicast address has organization scope. 295 * 296 * @return a <code>boolean</code> indicating if the address has 297 * is a multicast address of organization-local scope, 298 * false if it is not of organization-local scope 299 * or it is not a multicast address 300 * @since 1.4 301 */ isMCOrgLocal()302 public boolean isMCOrgLocal() { 303 // 239.192 - 239.195 304 int address = holder().getAddress(); 305 return (((address >>> 24) & 0xFF) == 239) 306 && (((address >>> 16) & 0xFF) >= 192) 307 && (((address >>> 16) & 0xFF) <= 195); 308 } 309 310 /** 311 * Returns the raw IP address of this <code>InetAddress</code> 312 * object. The result is in network byte order: the highest order 313 * byte of the address is in <code>getAddress()[0]</code>. 314 * 315 * @return the raw IP address of this object. 316 */ getAddress()317 public byte[] getAddress() { 318 int address = holder().getAddress(); 319 byte[] addr = new byte[INADDRSZ]; 320 321 addr[0] = (byte) ((address >>> 24) & 0xFF); 322 addr[1] = (byte) ((address >>> 16) & 0xFF); 323 addr[2] = (byte) ((address >>> 8) & 0xFF); 324 addr[3] = (byte) (address & 0xFF); 325 return addr; 326 } 327 328 /** 329 * Returns the IP address string in textual presentation form. 330 * 331 * @return the raw IP address in a string format. 332 * @since JDK1.0.2 333 */ getHostAddress()334 public String getHostAddress() { 335 return numericToTextFormat(getAddress()); 336 } 337 338 /** 339 * Returns a hashcode for this IP address. 340 * 341 * @return a hash code value for this IP address. 342 */ hashCode()343 public int hashCode() { 344 return holder().getAddress(); 345 } 346 347 /** 348 * Compares this object against the specified object. 349 * The result is <code>true</code> if and only if the argument is 350 * not <code>null</code> and it represents the same IP address as 351 * this object. 352 * <p> 353 * Two instances of <code>InetAddress</code> represent the same IP 354 * address if the length of the byte arrays returned by 355 * <code>getAddress</code> is the same for both, and each of the 356 * array components is the same for the byte arrays. 357 * 358 * @param obj the object to compare against. 359 * @return <code>true</code> if the objects are the same; 360 * <code>false</code> otherwise. 361 * @see java.net.InetAddress#getAddress() 362 */ equals(Object obj)363 public boolean equals(Object obj) { 364 return (obj != null) && (obj instanceof Inet4Address) && 365 (((InetAddress)obj).holder().getAddress() == holder().getAddress()); 366 } 367 368 // Utilities 369 /* 370 * Converts IPv4 binary address into a string suitable for presentation. 371 * 372 * @param src a byte array representing an IPv4 numeric address 373 * @return a String representing the IPv4 address in 374 * textual representation format 375 * @since 1.4 376 */ 377 numericToTextFormat(byte[] src)378 static String numericToTextFormat(byte[] src) 379 { 380 return (src[0] & 0xff) + "." + (src[1] & 0xff) + "." + (src[2] & 0xff) + "." + (src[3] & 0xff); 381 } 382 } 383