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/* * Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.net; import java.io.ObjectStreamException; /** * This class represents an Internet Protocol version 4 (IPv4) address. * Defined by <a href="http://www.ietf.org/rfc/rfc790.txt"> * <i>RFC 790: Assigned Numbers</i></a>, * <a href="http://www.ietf.org/rfc/rfc1918.txt"> * <i>RFC 1918: Address Allocation for Private Internets</i></a>, * and <a href="http://www.ietf.org/rfc/rfc2365.txt"><i>RFC 2365: * Administratively Scoped IP Multicast</i></a> * * <h2> <a id="format">Textual representation of IP addresses</a> </h2> * * Textual representation of IPv4 address used as input to methods * takes one of the following forms: * * <blockquote><ul style="list-style-type:none"> * <li>{@code d.d.d.d}</li> * <li>{@code d.d.d}</li> * <li>{@code d.d}</li> * <li>{@code d}</li> * </ul></blockquote> * * <p> When four parts are specified, each is interpreted as a byte of * data and assigned, from left to right, to the four bytes of an IPv4 * address. * <p> When a three part address is specified, the last part is * interpreted as a 16-bit quantity and placed in the right most two * bytes of the network address. This makes the three part address * format convenient for specifying Class B net- work addresses as * 128.net.host. * * <p> When a two part address is supplied, the last part is * interpreted as a 24-bit quantity and placed in the right most three * bytes of the network address. This makes the two part address * format convenient for specifying Class A network addresses as * net.host. * * <p> When only one part is given, the value is stored directly in * the network address without any byte rearrangement. * * <p> For methods that return a textual representation as output * value, the first form, i.e. a dotted-quad string, is used. * * <h3> The Scope of a Multicast Address </h3> * * Historically the IPv4 TTL field in the IP header has doubled as a * multicast scope field: a TTL of 0 means node-local, 1 means * link-local, up through 32 means site-local, up through 64 means * region-local, up through 128 means continent-local, and up through * 255 are global. However, the administrative scoping is preferred. * Please refer to <a href="http://www.ietf.org/rfc/rfc2365.txt"> * <i>RFC 2365: Administratively Scoped IP Multicast</i></a> * @since 1.4 */ public final class Inet4Address extends InetAddress { static final int INADDRSZ = 4; /** use serialVersionUID from InetAddress, but Inet4Address instance * is always replaced by an InetAddress instance before being * serialized */ private static final long serialVersionUID = 3286316764910316507L; /* * Perform initializations. */ static { init(); } Inet4Address() { super(); holder().hostName = null; holder().address = 0; holder().family = IPv4; } Inet4Address(String hostName, byte addr[]) { holder().hostName = hostName; holder().family = IPv4; if (addr != null) { if (addr.length == INADDRSZ) { int address = addr[3] & 0xFF; address |= ((addr[2] << 8) & 0xFF00); address |= ((addr[1] << 16) & 0xFF0000); address |= ((addr[0] << 24) & 0xFF000000); holder().address = address; } } holder().originalHostName = hostName; } Inet4Address(String hostName, int address) { holder().hostName = hostName; holder().family = IPv4; holder().address = address; holder().originalHostName = hostName; } /** * Replaces the object to be serialized with an InetAddress object. * * @return the alternate object to be serialized. * * @throws ObjectStreamException if a new object replacing this * object could not be created */ private Object writeReplace() throws ObjectStreamException { // will replace the to be serialized 'this' object InetAddress inet = new InetAddress(); inet.holder().hostName = holder().getHostName(); inet.holder().address = holder().getAddress(); /** * Prior to 1.4 an InetAddress was created with a family * based on the platform AF_INET value (usually 2). * For compatibility reasons we must therefore write * the InetAddress with this family. */ inet.holder().family = 2; return inet; } /** * Utility routine to check if the InetAddress is an * IP multicast address. IP multicast address is a Class D * address i.e first four bits of the address are 1110. * @return a {@code boolean} indicating if the InetAddress is * an IP multicast address */ public boolean isMulticastAddress() { return ((holder().getAddress() & 0xf0000000) == 0xe0000000); } /** * Utility routine to check if the InetAddress is a wildcard address. * @return a {@code boolean} indicating if the InetAddress is * a wildcard address. */ public boolean isAnyLocalAddress() { return holder().getAddress() == 0; } /** * Utility routine to check if the InetAddress is a loopback address. * * @return a {@code boolean} indicating if the InetAddress is * a loopback address; or false otherwise. */ public boolean isLoopbackAddress() { /* 127.x.x.x */ byte[] byteAddr = getAddress(); return byteAddr[0] == 127; } /** * Utility routine to check if the InetAddress is an link local address. * * @return a {@code boolean} indicating if the InetAddress is * a link local address; or false if address is not a link local unicast address. */ public boolean isLinkLocalAddress() { // link-local unicast in IPv4 (169.254.0.0/16) // defined in "Documenting Special Use IPv4 Address Blocks // that have been Registered with IANA" by Bill Manning // draft-manning-dsua-06.txt int address = holder().getAddress(); return (((address >>> 24) & 0xFF) == 169) && (((address >>> 16) & 0xFF) == 254); } /** * Utility routine to check if the InetAddress is a site local address. * * @return a {@code boolean} indicating if the InetAddress is * a site local address; or false if address is not a site local unicast address. */ public boolean isSiteLocalAddress() { // refer to RFC 1918 // 10/8 prefix // 172.16/12 prefix // 192.168/16 prefix int address = holder().getAddress(); return (((address >>> 24) & 0xFF) == 10) || ((((address >>> 24) & 0xFF) == 172) && (((address >>> 16) & 0xF0) == 16)) || ((((address >>> 24) & 0xFF) == 192) && (((address >>> 16) & 0xFF) == 168)); } /** * Utility routine to check if the multicast address has global scope. * * @return a {@code boolean} indicating if the address has * is a multicast address of global scope, false if it is not * of global scope or it is not a multicast address */ public boolean isMCGlobal() { // 224.0.1.0 to 238.255.255.255 byte[] byteAddr = getAddress(); return ((byteAddr[0] & 0xff) >= 224 && (byteAddr[0] & 0xff) <= 238) && !((byteAddr[0] & 0xff) == 224 && byteAddr[1] == 0 && byteAddr[2] == 0); } /** * Utility routine to check if the multicast address has node scope. * * @return a {@code boolean} indicating if the address has * is a multicast address of node-local scope, false if it is not * of node-local scope or it is not a multicast address */ public boolean isMCNodeLocal() { // unless ttl == 0 return false; } /** * Utility routine to check if the multicast address has link scope. * * @return a {@code boolean} indicating if the address has * is a multicast address of link-local scope, false if it is not * of link-local scope or it is not a multicast address */ public boolean isMCLinkLocal() { // 224.0.0/24 prefix and ttl == 1 int address = holder().getAddress(); return (((address >>> 24) & 0xFF) == 224) && (((address >>> 16) & 0xFF) == 0) && (((address >>> 8) & 0xFF) == 0); } /** * Utility routine to check if the multicast address has site scope. * * @return a {@code boolean} indicating if the address has * is a multicast address of site-local scope, false if it is not * of site-local scope or it is not a multicast address */ public boolean isMCSiteLocal() { // 239.255/16 prefix or ttl < 32 int address = holder().getAddress(); return (((address >>> 24) & 0xFF) == 239) && (((address >>> 16) & 0xFF) == 255); } /** * Utility routine to check if the multicast address has organization scope. * * @return a {@code boolean} indicating if the address has * is a multicast address of organization-local scope, * false if it is not of organization-local scope * or it is not a multicast address */ public boolean isMCOrgLocal() { // 239.192 - 239.195 int address = holder().getAddress(); return (((address >>> 24) & 0xFF) == 239) && (((address >>> 16) & 0xFF) >= 192) && (((address >>> 16) & 0xFF) <= 195); } /** * Returns the raw IP address of this {@code InetAddress} * object. The result is in network byte order: the highest order * byte of the address is in {@code getAddress()[0]}. * * @return the raw IP address of this object. */ public byte[] getAddress() { int address = holder().getAddress(); byte[] addr = new byte[INADDRSZ]; addr[0] = (byte) ((address >>> 24) & 0xFF); addr[1] = (byte) ((address >>> 16) & 0xFF); addr[2] = (byte) ((address >>> 8) & 0xFF); addr[3] = (byte) (address & 0xFF); return addr; } /** * Returns the IP address string in textual presentation form. * * @return the raw IP address in a string format. */ public String getHostAddress() { return numericToTextFormat(getAddress()); } /** * Returns a hashcode for this IP address. * * @return a hash code value for this IP address. */ public int hashCode() { return holder().getAddress(); } /** * Compares this object against the specified object. * The result is {@code true} if and only if the argument is * not {@code null} and it represents the same IP address as * this object. * <p> * Two instances of {@code InetAddress} represent the same IP * address if the length of the byte arrays returned by * {@code getAddress} is the same for both, and each of the * array components is the same for the byte arrays. * * @param obj the object to compare against. * @return {@code true} if the objects are the same; * {@code false} otherwise. * @see java.net.InetAddress#getAddress() */ public boolean equals(Object obj) { return (obj != null) && (obj instanceof Inet4Address) && (((InetAddress) obj).holder().getAddress() == holder().getAddress()); } // Utilities /** * Converts IPv4 binary address into a string suitable for presentation. * * @param src a byte array representing an IPv4 numeric address * @return a String representing the IPv4 address in * textual representation format */ static String numericToTextFormat(byte[] src) { return (src[0] & 0xff) + "." + (src[1] & 0xff) + "." + (src[2] & 0xff) + "." + (src[3] & 0xff); } /** * Perform class load-time initializations. */ private static native void init(); }