--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/net/InetAddress.java Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,1493 @@
+/*
+ * Copyright 1995-2007 Sun Microsystems, Inc. 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. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.net;
+
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.Random;
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.ArrayList;
+import java.security.AccessController;
+import java.io.ObjectStreamException;
+import java.io.IOException;
+import sun.security.action.*;
+import sun.net.InetAddressCachePolicy;
+import sun.net.util.IPAddressUtil;
+import sun.misc.Service;
+import sun.net.spi.nameservice.*;
+
+/**
+ * This class represents an Internet Protocol (IP) address.
+ *
+ * <p> An IP address is either a 32-bit or 128-bit unsigned number
+ * used by IP, a lower-level protocol on which protocols like UDP and
+ * TCP are built. The IP address architecture is 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>, <a
+ * href="http://www.ietf.org/rfc/rfc2365.txt"><i>RFC 2365:
+ * Administratively Scoped IP Multicast</i></a>, and <a
+ * href="http://www.ietf.org/rfc/rfc2373.txt"><i>RFC 2373: IP
+ * Version 6 Addressing Architecture</i></a>. An instance of an
+ * InetAddress consists of an IP address and possibly its
+ * corresponding host name (depending on whether it is constructed
+ * with a host name or whether it has already done reverse host name
+ * resolution).
+ *
+ * <h4> Address types </h4>
+ *
+ * <blockquote><table cellspacing=2 summary="Description of unicast and multicast address types">
+ * <tr><th valign=top><i>unicast</i></th>
+ * <td>An identifier for a single interface. A packet sent to
+ * a unicast address is delivered to the interface identified by
+ * that address.
+ *
+ * <p> The Unspecified Address -- Also called anylocal or wildcard
+ * address. It must never be assigned to any node. It indicates the
+ * absence of an address. One example of its use is as the target of
+ * bind, which allows a server to accept a client connection on any
+ * interface, in case the server host has multiple interfaces.
+ *
+ * <p> The <i>unspecified</i> address must not be used as
+ * the destination address of an IP packet.
+ *
+ * <p> The <i>Loopback</i> Addresses -- This is the address
+ * assigned to the loopback interface. Anything sent to this
+ * IP address loops around and becomes IP input on the local
+ * host. This address is often used when testing a
+ * client.</td></tr>
+ * <tr><th valign=top><i>multicast</i></th>
+ * <td>An identifier for a set of interfaces (typically belonging
+ * to different nodes). A packet sent to a multicast address is
+ * delivered to all interfaces identified by that address.</td></tr>
+ * </table></blockquote>
+ *
+ * <h4> IP address scope </h4>
+ *
+ * <p> <i>Link-local</i> addresses are designed to be used for addressing
+ * on a single link for purposes such as auto-address configuration,
+ * neighbor discovery, or when no routers are present.
+ *
+ * <p> <i>Site-local</i> addresses are designed to be used for addressing
+ * inside of a site without the need for a global prefix.
+ *
+ * <p> <i>Global</i> addresses are unique across the internet.
+ *
+ * <h4> Textual representation of IP addresses </h4>
+ *
+ * The textual representation of an IP address is address family specific.
+ *
+ * <p>
+ *
+ * For IPv4 address format, please refer to <A
+ * HREF="Inet4Address.html#format">Inet4Address#format</A>; For IPv6
+ * address format, please refer to <A
+ * HREF="Inet6Address.html#format">Inet6Address#format</A>.
+ *
+ * <P>There is a <a href="doc-files/net-properties.html#Ipv4IPv6">couple of
+ * System Properties</a> affecting how IPv4 and IPv6 addresses are used.</P>
+ *
+ * <h4> Host Name Resolution </h4>
+ *
+ * Host name-to-IP address <i>resolution</i> is accomplished through
+ * the use of a combination of local machine configuration information
+ * and network naming services such as the Domain Name System (DNS)
+ * and Network Information Service(NIS). The particular naming
+ * services(s) being used is by default the local machine configured
+ * one. For any host name, its corresponding IP address is returned.
+ *
+ * <p> <i>Reverse name resolution</i> means that for any IP address,
+ * the host associated with the IP address is returned.
+ *
+ * <p> The InetAddress class provides methods to resolve host names to
+ * their IP addresses and vice versa.
+ *
+ * <h4> InetAddress Caching </h4>
+ *
+ * The InetAddress class has a cache to store successful as well as
+ * unsuccessful host name resolutions.
+ *
+ * <p> By default, when a security manager is installed, in order to
+ * protect against DNS spoofing attacks,
+ * the result of positive host name resolutions are
+ * cached forever. When a security manager is not installed, the default
+ * behavior is to cache entries for a finite (implementation dependent)
+ * period of time. The result of unsuccessful host
+ * name resolution is cached for a very short period of time (10
+ * seconds) to improve performance.
+ *
+ * <p> If the default behavior is not desired, then a Java security property
+ * can be set to a different Time-to-live (TTL) value for positive
+ * caching. Likewise, a system admin can configure a different
+ * negative caching TTL value when needed.
+ *
+ * <p> Two Java security properties control the TTL values used for
+ * positive and negative host name resolution caching:
+ *
+ * <blockquote>
+ * <dl>
+ * <dt><b>networkaddress.cache.ttl</b></dt>
+ * <dd>Indicates the caching policy for successful name lookups from
+ * the name service. The value is specified as as integer to indicate
+ * the number of seconds to cache the successful lookup. The default
+ * setting is to cache for an implementation specific period of time.
+ * <p>
+ * A value of -1 indicates "cache forever".
+ * </dd>
+ * <p>
+ * <dt><b>networkaddress.cache.negative.ttl</b> (default: 10)</dt>
+ * <dd>Indicates the caching policy for un-successful name lookups
+ * from the name service. The value is specified as as integer to
+ * indicate the number of seconds to cache the failure for
+ * un-successful lookups.
+ * <p>
+ * A value of 0 indicates "never cache".
+ * A value of -1 indicates "cache forever".
+ * </dd>
+ * </dl>
+ * </blockquote>
+ *
+ * @author Chris Warth
+ * @see java.net.InetAddress#getByAddress(byte[])
+ * @see java.net.InetAddress#getByAddress(java.lang.String, byte[])
+ * @see java.net.InetAddress#getAllByName(java.lang.String)
+ * @see java.net.InetAddress#getByName(java.lang.String)
+ * @see java.net.InetAddress#getLocalHost()
+ * @since JDK1.0
+ */
+public
+class InetAddress implements java.io.Serializable {
+ /**
+ * Specify the address family: Internet Protocol, Version 4
+ * @since 1.4
+ */
+ static final int IPv4 = 1;
+
+ /**
+ * Specify the address family: Internet Protocol, Version 6
+ * @since 1.4
+ */
+ static final int IPv6 = 2;
+
+ /* Specify address family preference */
+ static transient boolean preferIPv6Address = false;
+
+ /**
+ * @serial
+ */
+ String hostName;
+
+ /**
+ * Holds a 32-bit IPv4 address.
+ *
+ * @serial
+ */
+ int address;
+
+ /**
+ * Specifies the address family type, for instance, '1' for IPv4
+ * addresses, and '2' for IPv6 addresses.
+ *
+ * @serial
+ */
+ int family;
+
+ /* Used to store the name service provider */
+ private static List<NameService> nameServices = null;
+
+ /* Used to store the best available hostname */
+ private transient String canonicalHostName = null;
+
+ /** use serialVersionUID from JDK 1.0.2 for interoperability */
+ private static final long serialVersionUID = 3286316764910316507L;
+
+ /*
+ * Load net library into runtime, and perform initializations.
+ */
+ static {
+ preferIPv6Address = java.security.AccessController.doPrivileged(
+ new GetBooleanAction("java.net.preferIPv6Addresses")).booleanValue();
+ AccessController.doPrivileged(new LoadLibraryAction("net"));
+ init();
+ }
+
+ /**
+ * Constructor for the Socket.accept() method.
+ * This creates an empty InetAddress, which is filled in by
+ * the accept() method. This InetAddress, however, is not
+ * put in the address cache, since it is not created by name.
+ */
+ InetAddress() {
+ }
+
+ /**
+ * Replaces the de-serialized object with an Inet4Address object.
+ *
+ * @return the alternate object to the de-serialized object.
+ *
+ * @throws ObjectStreamException if a new object replacing this
+ * object could not be created
+ */
+ private Object readResolve() throws ObjectStreamException {
+ // will replace the deserialized 'this' object
+ return new Inet4Address(this.hostName, this.address);
+ }
+
+ /**
+ * Utility routine to check if the InetAddress is an
+ * IP multicast address.
+ * @return a <code>boolean</code> indicating if the InetAddress is
+ * an IP multicast address
+ * @since JDK1.1
+ */
+ public boolean isMulticastAddress() {
+ return false;
+ }
+
+ /**
+ * 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 false;
+ }
+
+ /**
+ * 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
+ */
+ public boolean isLoopbackAddress() {
+ return false;
+ }
+
+ /**
+ * 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() {
+ return false;
+ }
+
+ /**
+ * 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() {
+ return false;
+ }
+
+ /**
+ * 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() {
+ return false;
+ }
+
+ /**
+ * 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() {
+ 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() {
+ return false;
+ }
+
+ /**
+ * 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() {
+ return false;
+ }
+
+ /**
+ * 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() {
+ return false;
+ }
+
+
+ /**
+ * Test whether that address is reachable. Best effort is made by the
+ * implementation to try to reach the host, but firewalls and server
+ * configuration may block requests resulting in a unreachable status
+ * while some specific ports may be accessible.
+ * A typical implementation will use ICMP ECHO REQUESTs if the
+ * privilege can be obtained, otherwise it will try to establish
+ * a TCP connection on port 7 (Echo) of the destination host.
+ * <p>
+ * The timeout value, in milliseconds, indicates the maximum amount of time
+ * the try should take. If the operation times out before getting an
+ * answer, the host is deemed unreachable. A negative value will result
+ * in an IllegalArgumentException being thrown.
+ *
+ * @param timeout the time, in milliseconds, before the call aborts
+ * @return a <code>boolean</code> indicating if the address is reachable.
+ * @throws IOException if a network error occurs
+ * @throws IllegalArgumentException if <code>timeout</code> is negative.
+ * @since 1.5
+ */
+ public boolean isReachable(int timeout) throws IOException {
+ return isReachable(null, 0 , timeout);
+ }
+
+ /**
+ * Test whether that address is reachable. Best effort is made by the
+ * implementation to try to reach the host, but firewalls and server
+ * configuration may block requests resulting in a unreachable status
+ * while some specific ports may be accessible.
+ * A typical implementation will use ICMP ECHO REQUESTs if the
+ * privilege can be obtained, otherwise it will try to establish
+ * a TCP connection on port 7 (Echo) of the destination host.
+ * <p>
+ * The <code>network interface</code> and <code>ttl</code> parameters
+ * let the caller specify which network interface the test will go through
+ * and the maximum number of hops the packets should go through.
+ * A negative value for the <code>ttl</code> will result in an
+ * IllegalArgumentException being thrown.
+ * <p>
+ * The timeout value, in milliseconds, indicates the maximum amount of time
+ * the try should take. If the operation times out before getting an
+ * answer, the host is deemed unreachable. A negative value will result
+ * in an IllegalArgumentException being thrown.
+ *
+ * @param netif the NetworkInterface through which the
+ * test will be done, or null for any interface
+ * @param ttl the maximum numbers of hops to try or 0 for the
+ * default
+ * @param timeout the time, in milliseconds, before the call aborts
+ * @throws IllegalArgumentException if either <code>timeout</code>
+ * or <code>ttl</code> are negative.
+ * @return a <code>boolean</code>indicating if the address is reachable.
+ * @throws IOException if a network error occurs
+ * @since 1.5
+ */
+ public boolean isReachable(NetworkInterface netif, int ttl,
+ int timeout) throws IOException {
+ if (ttl < 0)
+ throw new IllegalArgumentException("ttl can't be negative");
+ if (timeout < 0)
+ throw new IllegalArgumentException("timeout can't be negative");
+
+ return impl.isReachable(this, timeout, netif, ttl);
+ }
+
+ /**
+ * Gets the host name for this IP address.
+ *
+ * <p>If this InetAddress was created with a host name,
+ * this host name will be remembered and returned;
+ * otherwise, a reverse name lookup will be performed
+ * and the result will be returned based on the system
+ * configured name lookup service. If a lookup of the name service
+ * is required, call
+ * {@link #getCanonicalHostName() getCanonicalHostName}.
+ *
+ * <p>If there is a security manager, its
+ * <code>checkConnect</code> method is first called
+ * with the hostname and <code>-1</code>
+ * as its arguments to see if the operation is allowed.
+ * If the operation is not allowed, it will return
+ * the textual representation of the IP address.
+ *
+ * @return the host name for this IP address, or if the operation
+ * is not allowed by the security check, the textual
+ * representation of the IP address.
+ *
+ * @see InetAddress#getCanonicalHostName
+ * @see SecurityManager#checkConnect
+ */
+ public String getHostName() {
+ return getHostName(true);
+ }
+
+ /**
+ * Returns the hostname for this address.
+ * If the host is equal to null, then this address refers to any
+ * of the local machine's available network addresses.
+ * this is package private so SocketPermission can make calls into
+ * here without a security check.
+ *
+ * <p>If there is a security manager, this method first
+ * calls its <code>checkConnect</code> method
+ * with the hostname and <code>-1</code>
+ * as its arguments to see if the calling code is allowed to know
+ * the hostname for this IP address, i.e., to connect to the host.
+ * If the operation is not allowed, it will return
+ * the textual representation of the IP address.
+ *
+ * @return the host name for this IP address, or if the operation
+ * is not allowed by the security check, the textual
+ * representation of the IP address.
+ *
+ * @param check make security check if true
+ *
+ * @see SecurityManager#checkConnect
+ */
+ String getHostName(boolean check) {
+ if (hostName == null) {
+ hostName = InetAddress.getHostFromNameService(this, check);
+ }
+ return hostName;
+ }
+
+ /**
+ * Gets the fully qualified domain name for this IP address.
+ * Best effort method, meaning we may not be able to return
+ * the FQDN depending on the underlying system configuration.
+ *
+ * <p>If there is a security manager, this method first
+ * calls its <code>checkConnect</code> method
+ * with the hostname and <code>-1</code>
+ * as its arguments to see if the calling code is allowed to know
+ * the hostname for this IP address, i.e., to connect to the host.
+ * If the operation is not allowed, it will return
+ * the textual representation of the IP address.
+ *
+ * @return the fully qualified domain name for this IP address,
+ * or if the operation is not allowed by the security check,
+ * the textual representation of the IP address.
+ *
+ * @see SecurityManager#checkConnect
+ *
+ * @since 1.4
+ */
+ public String getCanonicalHostName() {
+ if (canonicalHostName == null) {
+ canonicalHostName =
+ InetAddress.getHostFromNameService(this, true);
+ }
+ return canonicalHostName;
+ }
+
+ /**
+ * Returns the hostname for this address.
+ *
+ * <p>If there is a security manager, this method first
+ * calls its <code>checkConnect</code> method
+ * with the hostname and <code>-1</code>
+ * as its arguments to see if the calling code is allowed to know
+ * the hostname for this IP address, i.e., to connect to the host.
+ * If the operation is not allowed, it will return
+ * the textual representation of the IP address.
+ *
+ * @return the host name for this IP address, or if the operation
+ * is not allowed by the security check, the textual
+ * representation of the IP address.
+ *
+ * @param check make security check if true
+ *
+ * @see SecurityManager#checkConnect
+ */
+ private static String getHostFromNameService(InetAddress addr, boolean check) {
+ String host = null;
+ for (NameService nameService : nameServices) {
+ try {
+ // first lookup the hostname
+ host = nameService.getHostByAddr(addr.getAddress());
+
+ /* check to see if calling code is allowed to know
+ * the hostname for this IP address, ie, connect to the host
+ */
+ if (check) {
+ SecurityManager sec = System.getSecurityManager();
+ if (sec != null) {
+ sec.checkConnect(host, -1);
+ }
+ }
+
+ /* now get all the IP addresses for this hostname,
+ * and make sure one of them matches the original IP
+ * address. We do this to try and prevent spoofing.
+ */
+
+ InetAddress[] arr = InetAddress.getAllByName0(host, check);
+ boolean ok = false;
+
+ if(arr != null) {
+ for(int i = 0; !ok && i < arr.length; i++) {
+ ok = addr.equals(arr[i]);
+ }
+ }
+
+ //XXX: if it looks a spoof just return the address?
+ if (!ok) {
+ host = addr.getHostAddress();
+ return host;
+ }
+
+ break;
+
+ } catch (SecurityException e) {
+ host = addr.getHostAddress();
+ break;
+ } catch (UnknownHostException e) {
+ host = addr.getHostAddress();
+ // let next provider resolve the hostname
+ }
+ }
+
+ return host;
+ }
+
+ /**
+ * 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() {
+ return null;
+ }
+
+ /**
+ * Returns the IP address string in textual presentation.
+ *
+ * @return the raw IP address in a string format.
+ * @since JDK1.0.2
+ */
+ public String getHostAddress() {
+ return null;
+ }
+
+ /**
+ * Returns a hashcode for this IP address.
+ *
+ * @return a hash code value for this IP address.
+ */
+ public int hashCode() {
+ return -1;
+ }
+
+ /**
+ * 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 false;
+ }
+
+ /**
+ * Converts this IP address to a <code>String</code>. The
+ * string returned is of the form: hostname / literal IP
+ * address.
+ *
+ * If the host name is unresolved, no reverse name service lookup
+ * is performed. The hostname part will be represented by an empty string.
+ *
+ * @return a string representation of this IP address.
+ */
+ public String toString() {
+ return ((hostName != null) ? hostName : "")
+ + "/" + getHostAddress();
+ }
+
+ /*
+ * Cached addresses - our own litle nis, not!
+ */
+ private static Cache addressCache = new Cache(Cache.Type.Positive);
+
+ private static Cache negativeCache = new Cache(Cache.Type.Negative);
+
+ private static boolean addressCacheInit = false;
+
+ static InetAddress[] unknown_array; // put THIS in cache
+
+ static InetAddressImpl impl;
+
+ private static HashMap lookupTable = new HashMap();
+
+ /**
+ * Represents a cache entry
+ */
+ static final class CacheEntry {
+
+ CacheEntry(Object address, long expiration) {
+ this.address = address;
+ this.expiration = expiration;
+ }
+
+ Object address;
+ long expiration;
+ }
+
+ /**
+ * A cache that manages entries based on a policy specified
+ * at creation time.
+ */
+ static final class Cache {
+ private LinkedHashMap cache;
+ private Type type;
+
+ enum Type {Positive, Negative};
+
+ /**
+ * Create cache
+ */
+ public Cache(Type type) {
+ this.type = type;
+ cache = new LinkedHashMap();
+ }
+
+ private int getPolicy() {
+ if (type == Type.Positive) {
+ return InetAddressCachePolicy.get();
+ } else {
+ return InetAddressCachePolicy.getNegative();
+ }
+ }
+
+ /**
+ * Add an entry to the cache. If there's already an
+ * entry then for this host then the entry will be
+ * replaced.
+ */
+ public Cache put(String host, Object address) {
+ int policy = getPolicy();
+ if (policy == InetAddressCachePolicy.NEVER) {
+ return this;
+ }
+
+ // purge any expired entries
+
+ if (policy != InetAddressCachePolicy.FOREVER) {
+
+ // As we iterate in insertion order we can
+ // terminate when a non-expired entry is found.
+ LinkedList expired = new LinkedList();
+ Iterator i = cache.keySet().iterator();
+ long now = System.currentTimeMillis();
+ while (i.hasNext()) {
+ String key = (String)i.next();
+ CacheEntry entry = (CacheEntry)cache.get(key);
+
+ if (entry.expiration >= 0 && entry.expiration < now) {
+ expired.add(key);
+ } else {
+ break;
+ }
+ }
+
+ i = expired.iterator();
+ while (i.hasNext()) {
+ cache.remove(i.next());
+ }
+ }
+
+ // create new entry and add it to the cache
+ // -- as a HashMap replaces existing entries we
+ // don't need to explicitly check if there is
+ // already an entry for this host.
+ long expiration;
+ if (policy == InetAddressCachePolicy.FOREVER) {
+ expiration = -1;
+ } else {
+ expiration = System.currentTimeMillis() + (policy * 1000);
+ }
+ CacheEntry entry = new CacheEntry(address, expiration);
+ cache.put(host, entry);
+ return this;
+ }
+
+ /**
+ * Query the cache for the specific host. If found then
+ * return its CacheEntry, or null if not found.
+ */
+ public CacheEntry get(String host) {
+ int policy = getPolicy();
+ if (policy == InetAddressCachePolicy.NEVER) {
+ return null;
+ }
+ CacheEntry entry = (CacheEntry)cache.get(host);
+
+ // check if entry has expired
+ if (entry != null && policy != InetAddressCachePolicy.FOREVER) {
+ if (entry.expiration >= 0 &&
+ entry.expiration < System.currentTimeMillis()) {
+ cache.remove(host);
+ entry = null;
+ }
+ }
+
+ return entry;
+ }
+ }
+
+ /*
+ * Initialize cache and insert anyLocalAddress into the
+ * unknown array with no expiry.
+ */
+ private static void cacheInitIfNeeded() {
+ assert Thread.holdsLock(addressCache);
+ if (addressCacheInit) {
+ return;
+ }
+ unknown_array = new InetAddress[1];
+ unknown_array[0] = impl.anyLocalAddress();
+
+ addressCache.put(impl.anyLocalAddress().getHostName(),
+ unknown_array);
+
+ addressCacheInit = true;
+ }
+
+ /*
+ * Cache the given hostname and address.
+ */
+ private static void cacheAddress(String hostname, Object address,
+ boolean success) {
+ hostname = hostname.toLowerCase();
+ synchronized (addressCache) {
+ cacheInitIfNeeded();
+ if (success) {
+ addressCache.put(hostname, address);
+ } else {
+ negativeCache.put(hostname, address);
+ }
+ }
+ }
+
+ /*
+ * Lookup hostname in cache (positive & negative cache). If
+ * found return address, null if not found.
+ */
+ private static Object getCachedAddress(String hostname) {
+ hostname = hostname.toLowerCase();
+
+ // search both positive & negative caches
+
+ synchronized (addressCache) {
+ CacheEntry entry;
+
+ cacheInitIfNeeded();
+
+ entry = addressCache.get(hostname);
+ if (entry == null) {
+ entry = negativeCache.get(hostname);
+ }
+
+ if (entry != null) {
+ return entry.address;
+ }
+ }
+
+ // not found
+ return null;
+ }
+
+ private static NameService createNSProvider(String provider) {
+ if (provider == null)
+ return null;
+
+ NameService nameService = null;
+ if (provider.equals("default")) {
+ // initialize the default name service
+ nameService = new NameService() {
+ public InetAddress[] lookupAllHostAddr(String host)
+ throws UnknownHostException {
+ return impl.lookupAllHostAddr(host);
+ }
+ public String getHostByAddr(byte[] addr)
+ throws UnknownHostException {
+ return impl.getHostByAddr(addr);
+ }
+ };
+ } else {
+ final String providerName = provider;
+ try {
+ nameService = java.security.AccessController.doPrivileged(
+ new java.security.PrivilegedExceptionAction<NameService>() {
+ public NameService run() {
+ Iterator itr = Service.providers(NameServiceDescriptor.class);
+ while (itr.hasNext()) {
+ NameServiceDescriptor nsd
+ = (NameServiceDescriptor)itr.next();
+ if (providerName.
+ equalsIgnoreCase(nsd.getType()+","
+ +nsd.getProviderName())) {
+ try {
+ return nsd.createNameService();
+ } catch (Exception e) {
+ e.printStackTrace();
+ System.err.println(
+ "Cannot create name service:"
+ +providerName+": " + e);
+ }
+ }
+ }
+
+ return null;
+ }
+ }
+ );
+ } catch (java.security.PrivilegedActionException e) {
+ }
+ }
+
+ return nameService;
+ }
+
+ static {
+ // create the impl
+ impl = (new InetAddressImplFactory()).create();
+
+ // get name service if provided and requested
+ String provider = null;;
+ String propPrefix = "sun.net.spi.nameservice.provider.";
+ int n = 1;
+ nameServices = new ArrayList<NameService>();
+ provider = AccessController.doPrivileged(
+ new GetPropertyAction(propPrefix + n));
+ while (provider != null) {
+ NameService ns = createNSProvider(provider);
+ if (ns != null)
+ nameServices.add(ns);
+
+ n++;
+ provider = AccessController.doPrivileged(
+ new GetPropertyAction(propPrefix + n));
+ }
+
+ // if not designate any name services provider,
+ // creat a default one
+ if (nameServices.size() == 0) {
+ NameService ns = createNSProvider("default");
+ nameServices.add(ns);
+ }
+ }
+
+ /**
+ * Create an InetAddress based on the provided host name and IP address
+ * No name service is checked for the validity of the address.
+ *
+ * <p> The host name can either be a machine name, such as
+ * "<code>java.sun.com</code>", or a textual representation of its IP
+ * address.
+ * <p> No validity checking is done on the host name either.
+ *
+ * <p> If addr specifies an IPv4 address an instance of Inet4Address
+ * will be returned; otherwise, an instance of Inet6Address
+ * will be returned.
+ *
+ * <p> IPv4 address byte array must be 4 bytes long and IPv6 byte array
+ * must be 16 bytes long
+ *
+ * @param host the specified host
+ * @param addr the raw IP address in network byte order
+ * @return an InetAddress object created from the raw IP address.
+ * @exception UnknownHostException if IP address is of illegal length
+ * @since 1.4
+ */
+ public static InetAddress getByAddress(String host, byte[] addr)
+ throws UnknownHostException {
+ if (host != null && host.length() > 0 && host.charAt(0) == '[') {
+ if (host.charAt(host.length()-1) == ']') {
+ host = host.substring(1, host.length() -1);
+ }
+ }
+ if (addr != null) {
+ if (addr.length == Inet4Address.INADDRSZ) {
+ return new Inet4Address(host, addr);
+ } else if (addr.length == Inet6Address.INADDRSZ) {
+ byte[] newAddr
+ = IPAddressUtil.convertFromIPv4MappedAddress(addr);
+ if (newAddr != null) {
+ return new Inet4Address(host, newAddr);
+ } else {
+ return new Inet6Address(host, addr);
+ }
+ }
+ }
+ throw new UnknownHostException("addr is of illegal length");
+ }
+
+
+ /**
+ * Determines the IP address of a host, given the host's name.
+ *
+ * <p> The host name can either be a machine name, such as
+ * "<code>java.sun.com</code>", or a textual representation of its
+ * IP address. If a literal IP address is supplied, only the
+ * validity of the address format is checked.
+ *
+ * <p> For <code>host</code> specified in literal IPv6 address,
+ * either the form defined in RFC 2732 or the literal IPv6 address
+ * format defined in RFC 2373 is accepted. IPv6 scoped addresses are also
+ * supported. See <a href="Inet6Address.html#scoped">here</a> for a description of IPv6
+ * scoped addresses.
+ *
+ * <p> If the host is <tt>null</tt> then an <tt>InetAddress</tt>
+ * representing an address of the loopback interface is returned.
+ * See <a href="http://www.ietf.org/rfc/rfc3330.txt">RFC 3330</a>
+ * section 2 and <a href="http://www.ietf.org/rfc/rfc2373.txt">RFC 2373</a>
+ * section 2.5.3. </p>
+ *
+ * @param host the specified host, or <code>null</code>.
+ * @return an IP address for the given host name.
+ * @exception UnknownHostException if no IP address for the
+ * <code>host</code> could be found, or if a scope_id was specified
+ * for a global IPv6 address.
+ * @exception SecurityException if a security manager exists
+ * and its checkConnect method doesn't allow the operation
+ */
+ public static InetAddress getByName(String host)
+ throws UnknownHostException {
+ return InetAddress.getAllByName(host)[0];
+ }
+
+ /**
+ * Given the name of a host, returns an array of its IP addresses,
+ * based on the configured name service on the system.
+ *
+ * <p> The host name can either be a machine name, such as
+ * "<code>java.sun.com</code>", or a textual representation of its IP
+ * address. If a literal IP address is supplied, only the
+ * validity of the address format is checked.
+ *
+ * <p> For <code>host</code> specified in <i>literal IPv6 address</i>,
+ * either the form defined in RFC 2732 or the literal IPv6 address
+ * format defined in RFC 2373 is accepted. A literal IPv6 address may
+ * also be qualified by appending a scoped zone identifier or scope_id.
+ * The syntax and usage of scope_ids is described
+ * <a href="Inet6Address.html#scoped">here</a>.
+ * <p> If the host is <tt>null</tt> then an <tt>InetAddress</tt>
+ * representing an address of the loopback interface is returned.
+ * See <a href="http://www.ietf.org/rfc/rfc3330.txt">RFC 3330</a>
+ * section 2 and <a href="http://www.ietf.org/rfc/rfc2373.txt">RFC 2373</a>
+ * section 2.5.3. </p>
+ *
+ * <p> If there is a security manager and <code>host</code> is not
+ * null and <code>host.length() </code> is not equal to zero, the
+ * security manager's
+ * <code>checkConnect</code> method is called
+ * with the hostname and <code>-1</code>
+ * as its arguments to see if the operation is allowed.
+ *
+ * @param host the name of the host, or <code>null</code>.
+ * @return an array of all the IP addresses for a given host name.
+ *
+ * @exception UnknownHostException if no IP address for the
+ * <code>host</code> could be found, or if a scope_id was specified
+ * for a global IPv6 address.
+ * @exception SecurityException if a security manager exists and its
+ * <code>checkConnect</code> method doesn't allow the operation.
+ *
+ * @see SecurityManager#checkConnect
+ */
+ public static InetAddress[] getAllByName(String host)
+ throws UnknownHostException {
+
+ if (host == null || host.length() == 0) {
+ InetAddress[] ret = new InetAddress[1];
+ ret[0] = impl.loopbackAddress();
+ return ret;
+ }
+
+ boolean ipv6Expected = false;
+ if (host.charAt(0) == '[') {
+ // This is supposed to be an IPv6 litteral
+ if (host.length() > 2 && host.charAt(host.length()-1) == ']') {
+ host = host.substring(1, host.length() -1);
+ ipv6Expected = true;
+ } else {
+ // This was supposed to be a IPv6 address, but it's not!
+ throw new UnknownHostException(host);
+ }
+ }
+
+ // if host is an IP address, we won't do further lookup
+ if (Character.digit(host.charAt(0), 16) != -1
+ || (host.charAt(0) == ':')) {
+ byte[] addr = null;
+ int numericZone = -1;
+ String ifname = null;
+ // see if it is IPv4 address
+ addr = IPAddressUtil.textToNumericFormatV4(host);
+ if (addr == null) {
+ // see if it is IPv6 address
+ // Check if a numeric or string zone id is present
+ int pos;
+ if ((pos=host.indexOf ("%")) != -1) {
+ numericZone = checkNumericZone (host);
+ if (numericZone == -1) { /* remainder of string must be an ifname */
+ ifname = host.substring (pos+1);
+ }
+ }
+ addr = IPAddressUtil.textToNumericFormatV6(host);
+ } else if (ipv6Expected) {
+ // Means an IPv4 litteral between brackets!
+ throw new UnknownHostException("["+host+"]");
+ }
+ InetAddress[] ret = new InetAddress[1];
+ if(addr != null) {
+ if (addr.length == Inet4Address.INADDRSZ) {
+ ret[0] = new Inet4Address(null, addr);
+ } else {
+ if (ifname != null) {
+ ret[0] = new Inet6Address(null, addr, ifname);
+ } else {
+ ret[0] = new Inet6Address(null, addr, numericZone);
+ }
+ }
+ return ret;
+ }
+ } else if (ipv6Expected) {
+ // We were expecting an IPv6 Litteral, but got something else
+ throw new UnknownHostException("["+host+"]");
+ }
+ return getAllByName0(host);
+ }
+
+ /**
+ * Returns the loopback address.
+ * <p>
+ * The InetAddress returned will represent the IPv4
+ * loopback address, 127.0.0.1, or the IPv6 loopback
+ * address, ::1. The IPv4 loopback address returned
+ * is only one of many in the form 127.*.*.*
+ *
+ * @return the InetAddress loopback instance.
+ * @since 1.7
+ */
+ public static InetAddress getLoopbackAddress() {
+ return impl.loopbackAddress();
+ }
+
+
+ /**
+ * check if the literal address string has %nn appended
+ * returns -1 if not, or the numeric value otherwise.
+ *
+ * %nn may also be a string that represents the displayName of
+ * a currently available NetworkInterface.
+ */
+ private static int checkNumericZone (String s) throws UnknownHostException {
+ int percent = s.indexOf ('%');
+ int slen = s.length();
+ int digit, zone=0;
+ if (percent == -1) {
+ return -1;
+ }
+ for (int i=percent+1; i<slen; i++) {
+ char c = s.charAt(i);
+ if (c == ']') {
+ if (i == percent+1) {
+ /* empty per-cent field */
+ return -1;
+ }
+ break;
+ }
+ if ((digit = Character.digit (c, 10)) < 0) {
+ return -1;
+ }
+ zone = (zone * 10) + digit;
+ }
+ return zone;
+ }
+
+ private static InetAddress[] getAllByName0 (String host)
+ throws UnknownHostException
+ {
+ return getAllByName0(host, true);
+ }
+
+ /**
+ * package private so SocketPermission can call it
+ */
+ static InetAddress[] getAllByName0 (String host, boolean check)
+ throws UnknownHostException {
+ /* If it gets here it is presumed to be a hostname */
+ /* Cache.get can return: null, unknownAddress, or InetAddress[] */
+ Object obj = null;
+ Object objcopy = null;
+
+ /* make sure the connection to the host is allowed, before we
+ * give out a hostname
+ */
+ if (check) {
+ SecurityManager security = System.getSecurityManager();
+ if (security != null) {
+ security.checkConnect(host, -1);
+ }
+ }
+
+ obj = getCachedAddress(host);
+
+ /* If no entry in cache, then do the host lookup */
+ if (obj == null) {
+ obj = getAddressFromNameService(host);
+ }
+
+ if (obj == unknown_array)
+ throw new UnknownHostException(host);
+
+ /* Make a copy of the InetAddress array */
+ objcopy = ((InetAddress [])obj).clone();
+
+ return (InetAddress [])objcopy;
+ }
+
+ private static Object getAddressFromNameService(String host)
+ throws UnknownHostException
+ {
+ Object obj = null;
+ boolean success = false;
+ UnknownHostException ex = null;
+
+ // Check whether the host is in the lookupTable.
+ // 1) If the host isn't in the lookupTable when
+ // checkLookupTable() is called, checkLookupTable()
+ // would add the host in the lookupTable and
+ // return null. So we will do the lookup.
+ // 2) If the host is in the lookupTable when
+ // checkLookupTable() is called, the current thread
+ // would be blocked until the host is removed
+ // from the lookupTable. Then this thread
+ // should try to look up the addressCache.
+ // i) if it found the address in the
+ // addressCache, checkLookupTable() would
+ // return the address.
+ // ii) if it didn't find the address in the
+ // addressCache for any reason,
+ // it should add the host in the
+ // lookupTable and return null so the
+ // following code would do a lookup itself.
+ if ((obj = checkLookupTable(host)) == null) {
+ // This is the first thread which looks up the address
+ // this host or the cache entry for this host has been
+ // expired so this thread should do the lookup.
+ for (NameService nameService : nameServices) {
+ try {
+ /*
+ * Do not put the call to lookup() inside the
+ * constructor. if you do you will still be
+ * allocating space when the lookup fails.
+ */
+
+ obj = nameService.lookupAllHostAddr(host);
+ success = true;
+ break;
+ } catch (UnknownHostException uhe) {
+ if (host.equalsIgnoreCase("localhost")) {
+ InetAddress[] local = new InetAddress[] { impl.loopbackAddress() };
+ obj = local;
+ success = true;
+ break;
+ }
+ else {
+ obj = unknown_array;
+ success = false;
+ ex = uhe;
+ }
+ }
+ }
+
+ // Cache the address.
+ cacheAddress(host, obj, success);
+ // Delete the host from the lookupTable, and
+ // notify all threads waiting for the monitor
+ // for lookupTable.
+ updateLookupTable(host);
+ if (!success && ex != null)
+ throw ex;
+ }
+
+ return obj;
+ }
+
+
+ private static Object checkLookupTable(String host) {
+ // make sure obj is null.
+ Object obj = null;
+
+ synchronized (lookupTable) {
+ // If the host isn't in the lookupTable, add it in the
+ // lookuptable and return null. The caller should do
+ // the lookup.
+ if (lookupTable.containsKey(host) == false) {
+ lookupTable.put(host, null);
+ return obj;
+ }
+
+ // If the host is in the lookupTable, it means that another
+ // thread is trying to look up the address of this host.
+ // This thread should wait.
+ while (lookupTable.containsKey(host)) {
+ try {
+ lookupTable.wait();
+ } catch (InterruptedException e) {
+ }
+ }
+ }
+
+ // The other thread has finished looking up the address of
+ // the host. This thread should retry to get the address
+ // from the addressCache. If it doesn't get the address from
+ // the cache, it will try to look up the address itself.
+ obj = getCachedAddress(host);
+ if (obj == null) {
+ synchronized (lookupTable) {
+ lookupTable.put(host, null);
+ }
+ }
+
+ return obj;
+ }
+
+ private static void updateLookupTable(String host) {
+ synchronized (lookupTable) {
+ lookupTable.remove(host);
+ lookupTable.notifyAll();
+ }
+ }
+
+ /**
+ * Returns an <code>InetAddress</code> object given the raw IP address .
+ * The argument is in network byte order: the highest order
+ * byte of the address is in <code>getAddress()[0]</code>.
+ *
+ * <p> This method doesn't block, i.e. no reverse name service lookup
+ * is performed.
+ *
+ * <p> IPv4 address byte array must be 4 bytes long and IPv6 byte array
+ * must be 16 bytes long
+ *
+ * @param addr the raw IP address in network byte order
+ * @return an InetAddress object created from the raw IP address.
+ * @exception UnknownHostException if IP address is of illegal length
+ * @since 1.4
+ */
+ public static InetAddress getByAddress(byte[] addr)
+ throws UnknownHostException {
+ return getByAddress(null, addr);
+ }
+
+ private static InetAddress cachedLocalHost = null;
+ private static long cacheTime = 0;
+ private static final long maxCacheTime = 5000L;
+ private static final Object cacheLock = new Object();
+
+ /**
+ * Returns the address of the local host. This is achieved by retrieving
+ * the name of the host from the system, then resolving that name into
+ * an <code>InetAddress</code>.
+ *
+ * <P>Note: The resolved address may be cached for a short period of time.
+ * </P>
+ *
+ * <p>If there is a security manager, its
+ * <code>checkConnect</code> method is called
+ * with the local host name and <code>-1</code>
+ * as its arguments to see if the operation is allowed.
+ * If the operation is not allowed, an InetAddress representing
+ * the loopback address is returned.
+ *
+ * @return the address of the local host.
+ *
+ * @exception UnknownHostException if the local host name could not
+ * be resolved into an address.
+ *
+ * @see SecurityManager#checkConnect
+ * @see java.net.InetAddress#getByName(java.lang.String)
+ */
+ public static InetAddress getLocalHost() throws UnknownHostException {
+
+ SecurityManager security = System.getSecurityManager();
+ try {
+ String local = impl.getLocalHostName();
+
+ if (security != null) {
+ security.checkConnect(local, -1);
+ }
+
+ if (local.equals("localhost")) {
+ return impl.loopbackAddress();
+ }
+
+ InetAddress ret = null;
+ synchronized (cacheLock) {
+ long now = System.currentTimeMillis();
+ if (cachedLocalHost != null) {
+ if ((now - cacheTime) < maxCacheTime) // Less than 5s old?
+ ret = cachedLocalHost;
+ else
+ cachedLocalHost = null;
+ }
+
+ // we are calling getAddressFromNameService directly
+ // to avoid getting localHost from cache
+ if (ret == null) {
+ InetAddress[] localAddrs;
+ try {
+ localAddrs =
+ (InetAddress[]) InetAddress.getAddressFromNameService(local);
+ } catch (UnknownHostException uhe) {
+ throw new UnknownHostException(local + ": " + uhe.getMessage());
+ }
+ cachedLocalHost = localAddrs[0];
+ cacheTime = now;
+ ret = localAddrs[0];
+ }
+ }
+ return ret;
+ } catch (java.lang.SecurityException e) {
+ return impl.loopbackAddress();
+ }
+ }
+
+ /**
+ * Perform class load-time initializations.
+ */
+ private static native void init();
+
+
+ /*
+ * Returns the InetAddress representing anyLocalAddress
+ * (typically 0.0.0.0 or ::0)
+ */
+ static InetAddress anyLocalAddress() {
+ return impl.anyLocalAddress();
+ }
+
+ /*
+ * Load and instantiate an underlying impl class
+ */
+ static Object loadImpl(String implName) {
+ Object impl;
+
+ /*
+ * Property "impl.prefix" will be prepended to the classname
+ * of the implementation object we instantiate, to which we
+ * delegate the real work (like native methods). This
+ * property can vary across implementations of the java.
+ * classes. The default is an empty String "".
+ */
+ String prefix = AccessController.doPrivileged(
+ new GetPropertyAction("impl.prefix", ""));
+ impl = null;
+ try {
+ impl = Class.forName("java.net." + prefix + implName).newInstance();
+ } catch (ClassNotFoundException e) {
+ System.err.println("Class not found: java.net." + prefix +
+ implName + ":\ncheck impl.prefix property " +
+ "in your properties file.");
+ } catch (InstantiationException e) {
+ System.err.println("Could not instantiate: java.net." + prefix +
+ implName + ":\ncheck impl.prefix property " +
+ "in your properties file.");
+ } catch (IllegalAccessException e) {
+ System.err.println("Cannot access class: java.net." + prefix +
+ implName + ":\ncheck impl.prefix property " +
+ "in your properties file.");
+ }
+
+ if (impl == null) {
+ try {
+ impl = Class.forName(implName).newInstance();
+ } catch (Exception e) {
+ throw new Error("System property impl.prefix incorrect");
+ }
+ }
+
+ return impl;
+ }
+}
+
+/*
+ * Simple factory to create the impl
+ */
+class InetAddressImplFactory {
+
+ static InetAddressImpl create() {
+ Object o;
+ if (isIPv6Supported()) {
+ o = InetAddress.loadImpl("Inet6AddressImpl");
+ } else {
+ o = InetAddress.loadImpl("Inet4AddressImpl");
+ }
+ return (InetAddressImpl)o;
+ }
+
+ static native boolean isIPv6Supported();
+}