1 /* 2 * Copyright (C) 2014 The Android Open Source Project 3 * Copyright (c) 2000, 2017, 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 790: Assigned Numbers</i></a>, 36 * <a href="http://www.ietf.org/rfc/rfc1918.txt"> 37 * <i>RFC 1918: Address Allocation for Private Internets</i></a>, 38 * and <a href="http://www.ietf.org/rfc/rfc2365.txt"><i>RFC 2365: 39 * Administratively Scoped IP Multicast</i></a> 40 * 41 * <h3> <a id="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><ul style="list-style-type:none"> 47 * <li>{@code d.d.d.d}</li> 48 * <li>{@code d.d.d}</li> 49 * <li>{@code d.d}</li> 50 * <li>{@code d}</li> 51 * </ul></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 2365: Administratively Scoped IP Multicast</i></a> 84 * @since 1.4 85 */ 86 87 public final 88 class Inet4Address extends InetAddress { 89 static final 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 /** 98 * Reserved address for {@code INADDR_ANY}, to specify any IPv4 address at all. 99 * 100 * @hide 101 */ 102 public static final InetAddress ANY = new Inet4Address(null, new byte[] { 0, 0, 0, 0 }); 103 104 /** 105 * Broadcast address to transmit to all devices on network. 106 * 107 * @hide 108 */ 109 public static final InetAddress ALL = 110 new Inet4Address(null, new byte[] { (byte) 255, (byte) 255, 111 (byte) 255, (byte) 255 }); 112 113 /** 114 * Loopback address to the local host. 115 * 116 * @hide 117 */ 118 public static final InetAddress LOOPBACK = 119 new Inet4Address("localhost", new byte[] { 127, 0, 0, 1 }); 120 // END Android-added: Define special-purpose IPv4 address. 121 122 123 // BEGIN Android-removed: Android doesn't need to call native init. 124 /* 125 * Perform initializations. 126 * 127 static { 128 init(); 129 } 130 */ 131 // END Android-removed: Android doesn't need to call native init. Inet4Address()132 Inet4Address() { 133 super(); 134 holder().hostName = null; 135 holder().address = 0; 136 holder().family = AF_INET; 137 } 138 Inet4Address(String hostName, byte addr[])139 Inet4Address(String hostName, byte addr[]) { 140 holder().hostName = hostName; 141 holder().family = AF_INET; 142 if (addr != null) { 143 if (addr.length == INADDRSZ) { 144 int address = addr[3] & 0xFF; 145 address |= ((addr[2] << 8) & 0xFF00); 146 address |= ((addr[1] << 16) & 0xFF0000); 147 address |= ((addr[0] << 24) & 0xFF000000); 148 holder().address = address; 149 } 150 } 151 holder().originalHostName = hostName; 152 } Inet4Address(String hostName, int address)153 Inet4Address(String hostName, int address) { 154 holder().hostName = hostName; 155 holder().family = AF_INET; 156 holder().address = address; 157 holder().originalHostName = hostName; 158 } 159 160 /** 161 * Replaces the object to be serialized with an InetAddress object. 162 * 163 * @return the alternate object to be serialized. 164 * 165 * @throws ObjectStreamException if a new object replacing this 166 * object could not be created 167 */ writeReplace()168 private Object writeReplace() throws ObjectStreamException { 169 // will replace the to be serialized 'this' object 170 InetAddress inet = new InetAddress(); 171 inet.holder().hostName = holder().getHostName(); 172 inet.holder().address = holder().getAddress(); 173 174 /** 175 * Prior to 1.4 an InetAddress was created with a family 176 * based on the platform AF_INET value (usually 2). 177 * For compatibility reasons we must therefore write the 178 * the InetAddress with this family. 179 */ 180 inet.holder().family = 2; 181 182 return inet; 183 } 184 185 /** 186 * Utility routine to check if the InetAddress is an 187 * IP multicast address. IP multicast address is a Class D 188 * address i.e first four bits of the address are 1110. 189 * @return a {@code boolean} indicating if the InetAddress is 190 * an IP multicast address 191 */ isMulticastAddress()192 public boolean isMulticastAddress() { 193 return ((holder().getAddress() & 0xf0000000) == 0xe0000000); 194 } 195 196 /** 197 * Utility routine to check if the InetAddress is a wildcard address. 198 * @return a {@code boolean} indicating if the Inetaddress is 199 * a wildcard address. 200 */ isAnyLocalAddress()201 public boolean isAnyLocalAddress() { 202 return holder().getAddress() == 0; 203 } 204 205 /** 206 * Utility routine to check if the InetAddress is a loopback address. 207 * 208 * @return a {@code boolean} indicating if the InetAddress is 209 * a loopback address; or false otherwise. 210 */ isLoopbackAddress()211 public boolean isLoopbackAddress() { 212 /* 127.x.x.x */ 213 byte[] byteAddr = getAddress(); 214 return byteAddr[0] == 127; 215 } 216 217 /** 218 * Utility routine to check if the InetAddress is an link local address. 219 * 220 * @return a {@code boolean} indicating if the InetAddress is 221 * a link local address; or false if address is not a link local unicast address. 222 */ isLinkLocalAddress()223 public boolean isLinkLocalAddress() { 224 // link-local unicast in IPv4 (169.254.0.0/16) 225 // defined in "Documenting Special Use IPv4 Address Blocks 226 // that have been Registered with IANA" by Bill Manning 227 // draft-manning-dsua-06.txt 228 int address = holder().getAddress(); 229 return (((address >>> 24) & 0xFF) == 169) 230 && (((address >>> 16) & 0xFF) == 254); 231 } 232 233 /** 234 * Utility routine to check if the InetAddress is a site local address. 235 * 236 * @return a {@code boolean} indicating if the InetAddress is 237 * a site local address; or false if address is not a site local unicast address. 238 */ isSiteLocalAddress()239 public boolean isSiteLocalAddress() { 240 // refer to RFC 1918 241 // 10/8 prefix 242 // 172.16/12 prefix 243 // 192.168/16 prefix 244 int address = holder().getAddress(); 245 return (((address >>> 24) & 0xFF) == 10) 246 || ((((address >>> 24) & 0xFF) == 172) 247 && (((address >>> 16) & 0xF0) == 16)) 248 || ((((address >>> 24) & 0xFF) == 192) 249 && (((address >>> 16) & 0xFF) == 168)); 250 } 251 252 /** 253 * Utility routine to check if the multicast address has global scope. 254 * 255 * @return a {@code boolean} indicating if the address has 256 * is a multicast address of global scope, false if it is not 257 * of global scope or it is not a multicast address 258 */ isMCGlobal()259 public boolean isMCGlobal() { 260 // 224.0.1.0 to 238.255.255.255 261 byte[] byteAddr = getAddress(); 262 return ((byteAddr[0] & 0xff) >= 224 && (byteAddr[0] & 0xff) <= 238 ) && 263 !((byteAddr[0] & 0xff) == 224 && byteAddr[1] == 0 && 264 byteAddr[2] == 0); 265 } 266 267 /** 268 * Utility routine to check if the multicast address has node scope. 269 * 270 * @return a {@code boolean} indicating if the address has 271 * is a multicast address of node-local scope, false if it is not 272 * of node-local scope or it is not a multicast address 273 */ isMCNodeLocal()274 public boolean isMCNodeLocal() { 275 // unless ttl == 0 276 return false; 277 } 278 279 /** 280 * Utility routine to check if the multicast address has link scope. 281 * 282 * @return a {@code boolean} indicating if the address has 283 * is a multicast address of link-local scope, false if it is not 284 * of link-local scope or it is not a multicast address 285 */ isMCLinkLocal()286 public boolean isMCLinkLocal() { 287 // 224.0.0/24 prefix and ttl == 1 288 int address = holder().getAddress(); 289 return (((address >>> 24) & 0xFF) == 224) 290 && (((address >>> 16) & 0xFF) == 0) 291 && (((address >>> 8) & 0xFF) == 0); 292 } 293 294 /** 295 * Utility routine to check if the multicast address has site scope. 296 * 297 * @return a {@code boolean} indicating if the address has 298 * is a multicast address of site-local scope, false if it is not 299 * of site-local scope or it is not a multicast address 300 */ isMCSiteLocal()301 public boolean isMCSiteLocal() { 302 // 239.255/16 prefix or ttl < 32 303 int address = holder().getAddress(); 304 return (((address >>> 24) & 0xFF) == 239) 305 && (((address >>> 16) & 0xFF) == 255); 306 } 307 308 /** 309 * Utility routine to check if the multicast address has organization scope. 310 * 311 * @return a {@code boolean} indicating if the address has 312 * is a multicast address of organization-local scope, 313 * false if it is not of organization-local scope 314 * or it is not a multicast address 315 */ isMCOrgLocal()316 public boolean isMCOrgLocal() { 317 // 239.192 - 239.195 318 int address = holder().getAddress(); 319 return (((address >>> 24) & 0xFF) == 239) 320 && (((address >>> 16) & 0xFF) >= 192) 321 && (((address >>> 16) & 0xFF) <= 195); 322 } 323 324 /** 325 * Returns the raw IP address of this {@code InetAddress} 326 * object. The result is in network byte order: the highest order 327 * byte of the address is in {@code getAddress()[0]}. 328 * 329 * @return the raw IP address of this object. 330 */ getAddress()331 public byte[] getAddress() { 332 int address = holder().getAddress(); 333 byte[] addr = new byte[INADDRSZ]; 334 335 addr[0] = (byte) ((address >>> 24) & 0xFF); 336 addr[1] = (byte) ((address >>> 16) & 0xFF); 337 addr[2] = (byte) ((address >>> 8) & 0xFF); 338 addr[3] = (byte) (address & 0xFF); 339 return addr; 340 } 341 342 /** 343 * Returns the IP address string in textual presentation form. 344 * 345 * @return the raw IP address in a string format. 346 */ getHostAddress()347 public String getHostAddress() { 348 return numericToTextFormat(getAddress()); 349 } 350 351 /** 352 * Returns a hashcode for this IP address. 353 * 354 * @return a hash code value for this IP address. 355 */ hashCode()356 public int hashCode() { 357 return holder().getAddress(); 358 } 359 360 /** 361 * Compares this object against the specified object. 362 * The result is {@code true} if and only if the argument is 363 * not {@code null} and it represents the same IP address as 364 * this object. 365 * <p> 366 * Two instances of {@code InetAddress} represent the same IP 367 * address if the length of the byte arrays returned by 368 * {@code getAddress} is the same for both, and each of the 369 * array components is the same for the byte arrays. 370 * 371 * @param obj the object to compare against. 372 * @return {@code true} if the objects are the same; 373 * {@code false} otherwise. 374 * @see java.net.InetAddress#getAddress() 375 */ equals(Object obj)376 public boolean equals(Object obj) { 377 return (obj != null) && (obj instanceof Inet4Address) && 378 (((InetAddress)obj).holder().getAddress() == holder().getAddress()); 379 } 380 381 // Utilities 382 383 /** 384 * Converts IPv4 binary address into a string suitable for presentation. 385 * 386 * @param src a byte array representing an IPv4 numeric address 387 * @return a String representing the IPv4 address in 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