/* * @(#)Inet4Address.java 1.27 06/10/10 * * Copyright 1990-2008 Sun Microsystems, Inc. All Rights Reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER * * This program 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. * * This program 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 at /legal/license.txt). * * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa * Clara, CA 95054 or visit www.sun.com if you need additional * information or have any questions. */ package java.net; import java.security.AccessController; import java.io.ObjectStreamException; import sun.security.action.*; /** * 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> * * <h4> <A NAME="format">Textual representation of IP addresses<a> </h4> * * Textual representation of IPv4 address used as input to methods * takes one of the following forms: * * <blockquote><table cellpadding=0 cellspacing=0 summary="layout"> * <tr><td><tt>d.d.d.d</tt><td></tr> * <tr><td><tt>d.d.d</tt><td></tr> * <tr><td><tt>d.d</td></tr> * <tr><td><tt>d</td></tr> * </table></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. * * <h4> The Scope of a Multicast Address </h4> * * 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> */ public final class Inet4Address extends InetAddress { final static 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(); hostName = null; address = 0; family = IPv4; } Inet4Address(String hostName, byte addr[]) { this.hostName = hostName; this.family = IPv4; if (addr != null) { if (addr.length == INADDRSZ) { address = addr[3] & 0xFF; address |= ((addr[2] << 8) & 0xFF00); address |= ((addr[1] << 16) & 0xFF0000); address |= ((addr[0] << 24) & 0xFF000000); } } } Inet4Address(String hostName, int address) { this.hostName = hostName; this.family = IPv4; this.address = address; } /** * 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.hostName = this.hostName; inet.address = this.address; /** * 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 * the InetAddress with this family. */ inet.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</code> indicating if the InetAddress is * an IP multicast address * @since JDK1.1 */ public boolean isMulticastAddress() { return ((address & 0xf0000000) == 0xe0000000); } /** * Utility routine to check if the InetAddress in a wildcard address. * @return a <code>boolean</code> indicating if the Inetaddress is * a wildcard address. * @since 1.4 */ public boolean isAnyLocalAddress() { return address == 0; } /** * Utility routine to check if the InetAddress is a loopback address. * * @return a <code>boolean</code> indicating if the InetAddress is * a loopback address; or false otherwise. * @since 1.4 */ private static final int loopback = 2130706433; /* 127.0.0.1 */ 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</code> indicating if the InetAddress is * a link local address; or false if address is not a link local unicast address. * @since 1.4 */ 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 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</code> indicating if the InetAddress is * a site local address; or false if address is not a site local unicast address. * @since 1.4 */ public boolean isSiteLocalAddress() { // refer to RFC 1918 // 10/8 prefix // 172.16/12 prefix // 192.168/16 prefix 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</code> 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 * @since 1.4 */ 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</code> 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 * @since 1.4 */ public boolean isMCNodeLocal() { // unless ttl == 0 return false; } /** * Utility routine to check if the multicast address has link scope. * * @return a <code>boolean</code> 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 * @since 1.4 */ public boolean isMCLinkLocal() { // 224.0.0/24 prefix and ttl == 1 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</code> 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 * @since 1.4 */ public boolean isMCSiteLocal() { // 239.255/16 prefix or ttl < 32 return (((address >>> 24) & 0xFF) == 239) && (((address >>> 16) & 0xFF) == 255); } /** * Utility routine to check if the multicast address has organization scope. * * @return a <code>boolean</code> 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 * @since 1.4 */ public boolean isMCOrgLocal() { // 239.192 - 239.195 return (((address >>> 24) & 0xFF) == 239) && (((address >>> 16) & 0xFF) >= 192) && (((address >>> 16) & 0xFF) <= 195); } /** * Returns the raw IP address of this <code>InetAddress</code> * object. The result is in network byte order: the highest order * byte of the address is in <code>getAddress()[0]</code>. * * @return the raw IP address of this object. */ public byte[] 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. * @since JDK1.0.2 */ 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 address; } /** * Compares this object against the specified object. * The result is <code>true</code> if and only if the argument is * not <code>null</code> and it represents the same IP address as * this object. * <p> * Two instances of <code>InetAddress</code> represent the same IP * address if the length of the byte arrays returned by * <code>getAddress</code> 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</code> if the objects are the same; * <code>false</code> otherwise. * @see java.net.InetAddress#getAddress() */ public boolean equals(Object obj) { return (obj != null) && (obj instanceof Inet4Address) && (((InetAddress)obj).address == address); } // 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 * @since 1.4 */ static String numericToTextFormat(byte[] src) { return (src[0] & 0xff) + "." + (src[1] & 0xff) + "." + (src[2] & 0xff) + "." + (src[3] & 0xff); } /* * Converts IPv4 address in its textual presentation form * into its numeric binary form. * * @param src a String representing an IPv4 address in standard format * @return a byte array representing the IPv4 numeric address * @since 1.4 */ static byte[] textToNumericFormat(String src) { if (src.length() == 0) { return null; } int octets; char ch; byte[] dst = new byte[INADDRSZ]; char[] srcb = src.toCharArray(); boolean saw_digit = false; octets = 0; int i = 0; int cur = 0; while (i < srcb.length) { ch = srcb[i++]; if (Character.isDigit(ch)) { // note that Java byte is signed, so need to convert to int int sum = (dst[cur] & 0xff)*10 + (Character.digit(ch, 10) & 0xff); if (sum > 255) return null; dst[cur] = (byte)(sum & 0xff); if (! saw_digit) { if (++octets > INADDRSZ) return null; saw_digit = true; } } else if (ch == '.' && saw_digit) { if (octets == INADDRSZ) return null; cur++; dst[cur] = 0; saw_digit = false; } else return null; } if (octets < INADDRSZ) return null; return dst; } /** * Perform class load-time initializations. */ private static native void init(); }