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/*
* Copyright (C) 2014 The Android Open Source Project
* Copyright (c) 1995, 2015, 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;
import java.io.ObjectStreamField;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectInputStream.GetField;
import java.io.ObjectOutputStream;
import java.io.ObjectOutputStream.PutField;
import libcore.net.InetAddressUtils;
import sun.net.util.IPAddressUtil;
import sun.net.spi.nameservice.*;
import libcore.io.Libcore;
/**
* This class represents an Internet Protocol (IP) address.
*
* 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 RFC 790:
* Assigned Numbers, RFC 1918:
* Address Allocation for Private Internets, RFC 2365:
* Administratively Scoped IP Multicast, and RFC 2373: IP
* Version 6 Addressing Architecture. 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).
*
*
Address types
*
*
* unicast
* An identifier for a single interface. A packet sent to
* a unicast address is delivered to the interface identified by
* that address.
*
* 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.
*
*
The unspecified address must not be used as
* the destination address of an IP packet.
*
*
The Loopback 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.
multicast
* 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.
*
* IP address scope
*
* Link-local 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.
*
*
Site-local addresses are designed to be used for addressing
* inside of a site without the need for a global prefix.
*
*
Global addresses are unique across the internet.
*
*
Textual representation of IP addresses
*
* The textual representation of an IP address is address family specific.
*
*
*
* For IPv4 address format, please refer to Inet4Address#format; For IPv6
* address format, please refer to Inet6Address#format.
*
*
There is a couple of
* System Properties affecting how IPv4 and IPv6 addresses are used.
*
* Host Name Resolution
*
* Host name-to-IP address resolution 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.
*
* Reverse name resolution means that for any IP address,
* the host associated with the IP address is returned.
*
*
The InetAddress class provides methods to resolve host names to
* their IP addresses and vice versa.
*
*
InetAddress Caching
*
* The InetAddress class has a cache to store successful as well as
* unsuccessful host name resolutions.
*
* 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.
*
*
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.
*
*
Two Java security properties control the TTL values used for
* positive and negative host name resolution caching:
*
*
*
* - networkaddress.cache.ttl
* - 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.
*
* A value of -1 indicates "cache forever".
*
* - networkaddress.cache.negative.ttl (default: 10)
* - 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.
*
* A value of 0 indicates "never cache".
* A value of -1 indicates "cache forever".
*
*
*
*
* @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 {
// BEGIN Android-removed: Android uses linux-based OsConstants.
/*
* 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;
*/
// END Android-removed: Android uses linux-based OsConstants.
// Android-removed: Android doesn't support the preference.
// /* Specify address family preference */
//static transient boolean preferIPv6Address = false;
static class InetAddressHolder {
/**
* Reserve the original application specified hostname.
*
* The original hostname is useful for domain-based endpoint
* identification (see RFC 2818 and RFC 6125). If an address
* was created with a raw IP address, a reverse name lookup
* may introduce endpoint identification security issue via
* DNS forging.
*
* Oracle JSSE provider is using this original hostname, via
* sun.misc.JavaNetAccess, for SSL/TLS endpoint identification.
*
* Note: May define a new public method in the future if necessary.
*/
String originalHostName;
InetAddressHolder() {}
InetAddressHolder(String hostName, int address, int family) {
this.originalHostName = hostName;
this.hostName = hostName;
this.address = address;
this.family = family;
}
void init(String hostName, int family) {
this.originalHostName = hostName;
this.hostName = hostName;
if (family != -1) {
this.family = family;
}
}
String hostName;
String getHostName() {
return hostName;
}
String getOriginalHostName() {
return originalHostName;
}
/**
* Holds a 32-bit IPv4 address.
*/
int address;
int getAddress() {
return address;
}
// Android-changed: Documentation: use Linux-based OsConstants.
/**
* Specifies the address family type, for instance, AF_INET for IPv4
* addresses, and AF_INET6 for IPv6 addresses.
*/
int family;
int getFamily() {
return family;
}
}
transient InetAddressHolder holder;
InetAddressHolder holder() {
return holder;
}
/* The implementation is always dual stack IPv6/IPv4 on android */
static final InetAddressImpl impl = new Inet6AddressImpl();
/* Used to store the name service provider */
// Android-changed: Android has only one name service.
// Android doesn't allow user to provide custom name services.
// private static List nameServices = null;
private static final NameService nameService = new NameService() {
public InetAddress[] lookupAllHostAddr(String host, int netId)
throws UnknownHostException {
return impl.lookupAllHostAddr(host, netId);
}
public String getHostByAddr(byte[] addr)
throws UnknownHostException {
return impl.getHostByAddr(addr);
}
};
/* 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;
// BEGIN Android-removed: Android doesn't need to load native library.
/*
* Load net library into runtime, and perform initializations.
*
static {
preferIPv6Address = java.security.AccessController.doPrivileged(
new GetBooleanAction("java.net.preferIPv6Addresses")).booleanValue();
AccessController.doPrivileged(
new java.security.PrivilegedAction() {
public Void run() {
System.loadLibrary("net");
return null;
}
});
init();
}
*/
// END Android-removed: Android doesn't need to load native library.
/**
* 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() {
holder = new InetAddressHolder();
}
/**
* 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(holder().getHostName(), holder().getAddress());
}
/**
* Utility routine to check if the InetAddress is an
* IP multicast address.
* @return a {@code boolean} 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} 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} 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} 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} 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} 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} 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} 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} 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} 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;
}
// Android-changed: Document that impl tries ICMP ECHO REQUESTs first.
// The sole implementation, Inet6AddressImpl.isReachable(), tries ICMP ECHO REQUESTs before
// TCP ECHO REQUESTs on Android. On Android, these are both possible without root access.
/**
* 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.
*
* Android implementation attempts ICMP ECHO REQUESTs first, on failure it
* will fall back to TCP ECHO REQUESTs. Success on either protocol will
* return true.
*
* 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} indicating if the address is reachable.
* @throws IOException if a network error occurs
* @throws IllegalArgumentException if {@code timeout} is negative.
* @since 1.5
*/
public boolean isReachable(int timeout) throws IOException {
return isReachable(null, 0 , timeout);
}
// Android-changed: Document that impl tries ICMP ECHO REQUESTs first.
// The sole implementation, Inet6AddressImpl.isReachable(), tries ICMP ECHO REQUESTs before
// TCP ECHO REQUESTs on Android. On Android, these are both possible without root access.
/**
* 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.
*
* Android implementation attempts ICMP ECHO REQUESTs first, on failure it
* will fall back to TCP ECHO REQUESTs. Success on either protocol will
* return true.
*
* The {@code network interface} and {@code ttl} 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} will result in an
* IllegalArgumentException being thrown.
*
* 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}
* or {@code ttl} are negative.
* @return a {@code boolean}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);
}
// BEGIN Android-added: isReachableByICMP(timeout).
/**
* @hide For testing only
*/
public boolean isReachableByICMP(int timeout) throws IOException {
return ((Inet6AddressImpl) impl).icmpEcho(this, timeout, null, 0);
}
// END Android-added: isReachableByICMP(timeout).
/**
* Gets the host name for this IP address.
*
*
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}.
*
*
If there is a security manager, its
* {@code checkConnect} method is first called
* with the hostname and {@code -1}
* 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() {
// Android-changed: Remove SecurityManager check.
if (holder().getHostName() == null) {
holder().hostName = InetAddress.getHostFromNameService(this);
}
return holder().getHostName();
}
// BEGIN Android-removed: Android doesn't support SecurityManager.
/*
* 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.
*
*
If there is a security manager, this method first
* calls its {@code checkConnect} method
* with the hostname and {@code -1}
* 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 (holder().getHostName() == null) {
holder().hostName = InetAddress.getHostFromNameService(this, check);
}
return holder().getHostName();
}
*/
// END Android-removed: Android doesn't support SecurityManager.
/**
* 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.
*
*
If there is a security manager, this method first
* calls its {@code checkConnect} method
* with the hostname and {@code -1}
* 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() {
// Android-changed: Remove SecurityManager check.
if (canonicalHostName == null) {
canonicalHostName = InetAddress.getHostFromNameService(this);
}
return canonicalHostName;
}
// Android-changed: Remove SecurityManager check.
// * @param check make security check if true
/**
* Returns the hostname for this address.
*
*
If there is a security manager, this method first
* calls its {@code checkConnect} method
* with the hostname and {@code -1}
* 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.
*
* @see SecurityManager#checkConnect
*/
private static String getHostFromNameService(InetAddress addr) {
String host = null;
try {
// first lookup the hostname
// Android-changed: Android has only one name service.
host = nameService.getHostByAddr(addr.getAddress());
/* 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 = nameService.lookupAllHostAddr(host, NETID_UNSET);
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;
}
} catch (UnknownHostException e) {
host = addr.getHostAddress();
}
return host;
}
/**
* 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() {
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} if and only if the argument is
* not {@code null} and it represents the same IP address as
* this object.
*
* 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 false;
}
/**
* Converts this IP address to a {@code String}. 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() {
String hostName = holder().getHostName();
return ((hostName != null) ? hostName : "")
+ "/" + getHostAddress();
}
// BEGIN Android-removed: Resolves a hostname using Libcore.os.
/*
* 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 final HashMap lookupTable = new HashMap<>();
/**
* Represents a cache entry
*
static final class CacheEntry {
CacheEntry(InetAddress[] addresses, long expiration) {
this.addresses = addresses;
this.expiration = expiration;
}
InetAddress[] addresses;
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, InetAddress[] addresses) {
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<>();
long now = System.currentTimeMillis();
for (String key : cache.keySet()) {
CacheEntry entry = cache.get(key);
if (entry.expiration >= 0 && entry.expiration < now) {
expired.add(key);
} else {
break;
}
}
for (String key : expired) {
cache.remove(key);
}
}
// 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(addresses, 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 = 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 addresses.
*
private static void cacheAddresses(String hostname,
InetAddress[] addresses,
boolean success) {
hostname = hostname.toLowerCase();
synchronized (addressCache) {
cacheInitIfNeeded();
if (success) {
addressCache.put(hostname, addresses);
} else {
negativeCache.put(hostname, addresses);
}
}
}
/*
* Lookup hostname in cache (positive & negative cache). If
* found return addresses, null if not found.
*
private static InetAddress[] getCachedAddresses(String hostname) {
hostname = hostname.toLowerCase();
// search both positive & negative caches
synchronized (addressCache) {
cacheInitIfNeeded();
CacheEntry entry = addressCache.get(hostname);
if (entry == null) {
entry = negativeCache.get(hostname);
}
if (entry != null) {
return entry.addresses;
}
}
// 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() {
public NameService run() {
Iterator itr =
ServiceLoader.load(NameServiceDescriptor.class)
.iterator();
while (itr.hasNext()) {
NameServiceDescriptor nsd = 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 = 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();
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,
// create a default one
if (nameServices.size() == 0) {
NameService ns = createNSProvider("default");
nameServices.add(ns);
}
}
*/
// END Android-removed: Resolves a hostname using Libcore.os.
/**
* Creates an InetAddress based on the provided host name and IP address.
* No name service is checked for the validity of the address.
*
* The host name can either be a machine name, such as
* "{@code java.sun.com}", or a textual representation of its IP
* address.
*
No validity checking is done on the host name either.
*
*
If addr specifies an IPv4 address an instance of Inet4Address
* will be returned; otherwise, an instance of Inet6Address
* will be returned.
*
*
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 {
return getByAddress(host, addr, -1 /* scopeId */);
}
// Android-added: Called by native code in Libcore.io.
// Do not delete. Called from native code.
private static InetAddress getByAddress(String host, byte[] addr, int scopeId)
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, scopeId);
}
}
}
throw new UnknownHostException("addr is of illegal length");
}
/**
* Determines the IP address of a host, given the host's name.
*
*
The host name can either be a machine name, such as
* "{@code java.sun.com}", or a textual representation of its
* IP address. If a literal IP address is supplied, only the
* validity of the address format is checked.
*
*
For {@code host} 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 here for a description of IPv6
* scoped addresses.
*
*
If the host is {@code null} then an {@code InetAddress}
* representing an address of the loopback interface is returned.
* See RFC 3330
* section 2 and RFC 2373
* section 2.5.3.
*
* @param host the specified host, or {@code null}.
* @return an IP address for the given host name.
* @exception UnknownHostException if no IP address for the
* {@code host} 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 {
// Android-changed: Rewritten on the top of Libcore.os.
return impl.lookupAllHostAddr(host, NETID_UNSET)[0];
}
/**
* Given the name of a host, returns an array of its IP addresses,
* based on the configured name service on the system.
*
* The host name can either be a machine name, such as
* "{@code java.sun.com}", or a textual representation of its IP
* address. If a literal IP address is supplied, only the
* validity of the address format is checked.
*
*
For {@code host} specified in literal IPv6 address,
* 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
* here.
*
If the host is {@code null} then an {@code InetAddress}
* representing an address of the loopback interface is returned.
* See RFC 3330
* section 2 and RFC 2373
* section 2.5.3.
*
* If there is a security manager and {@code host} is not
* null and {@code host.length() } is not equal to zero, the
* security manager's
* {@code checkConnect} method is called
* with the hostname and {@code -1}
* as its arguments to see if the operation is allowed.
*
* @param host the name of the host, or {@code null}.
* @return an array of all the IP addresses for a given host name.
*
* @exception UnknownHostException if no IP address for the
* {@code host} 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} method doesn't allow the operation.
*
* @see SecurityManager#checkConnect
*/
public static InetAddress[] getAllByName(String host)
throws UnknownHostException {
// Android-changed: Resolves a hostname using Libcore.os.
// Also, returns both the Inet4 and Inet6 loopback for null/empty host
return impl.lookupAllHostAddr(host, NETID_UNSET).clone();
}
/**
* Returns the loopback address.
*
* 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() {
// Android-changed: Always returns IPv6 loopback address in Android.
return impl.loopbackAddresses()[0];
}
// BEGIN Android-removed: Resolves a hostname using Libcore.os.
/*
* 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 1 && !addresses[0].equals(reqAddr)) {
// Find it?
int i = 1;
for (; i < addresses.length; i++) {
if (addresses[i].equals(reqAddr)) {
break;
}
}
// Rotate
if (i < addresses.length) {
InetAddress tmp, tmp2 = reqAddr;
for (int j = 0; j < i; j++) {
tmp = addresses[j];
addresses[j] = tmp2;
tmp2 = tmp;
}
addresses[i] = tmp2;
}
}
// Cache the address.
cacheAddresses(host, addresses, success);
if (!success && ex != null)
throw ex;
} finally {
// Delete host from the lookupTable and notify
// all threads waiting on the lookupTable monitor.
updateLookupTable(host);
}
}
return addresses;
}
private static InetAddress[] checkLookupTable(String host) {
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 null;
}
// If the host is in the lookupTable, it means that another
// thread is trying to look up the addresses 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 addresses of
// the host. This thread should retry to get the addresses
// from the addressCache. If it doesn't get the addresses from
// the cache, it will try to look up the addresses itself.
InetAddress[] addresses = getCachedAddresses(host);
if (addresses == null) {
synchronized (lookupTable) {
lookupTable.put(host, null);
return null;
}
}
return addresses;
}
private static void updateLookupTable(String host) {
synchronized (lookupTable) {
lookupTable.remove(host);
lookupTable.notifyAll();
}
}
*/
// END Android-removed: Resolves a hostname using Libcore.os.
/**
* Returns an {@code InetAddress} 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]}.
*
* This method doesn't block, i.e. no reverse name service lookup
* is performed.
*
*
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);
}
// BEGIN Android-removed: Resolves a hostname using Libcore.os.
/*
private static InetAddress cachedLocalHost = null;
private static long cacheTime = 0;
private static final long maxCacheTime = 5000L;
private static final Object cacheLock = new Object();
*/
// END Android-removed: Resolves a hostname using Libcore.os.
/**
* 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}.
*
*
Note: The resolved address may be cached for a short period of time.
*
*
* If there is a security manager, its
* {@code checkConnect} method is called
* with the local host name and {@code -1}
* 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 {
// BEGIN Android-changed: Resolves a hostname using Libcore.os.
/*
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 getAddressesFromNameService directly
// to avoid getting localHost from cache
if (ret == null) {
InetAddress[] localAddrs;
try {
localAddrs =
InetAddress.getAddressesFromNameService(local, null);
} catch (UnknownHostException uhe) {
// Rethrow with a more informative error message.
UnknownHostException uhe2 =
new UnknownHostException(local + ": " +
uhe.getMessage());
uhe2.initCause(uhe);
throw uhe2;
}
cachedLocalHost = localAddrs[0];
cacheTime = now;
ret = localAddrs[0];
}
}
return ret;
} catch (java.lang.SecurityException e) {
return impl.loopbackAddress();
}
*/
String local = Libcore.os.uname().nodename;
return impl.lookupAllHostAddr(local, NETID_UNSET)[0];
// END Android-changed: Resolves a hostname using Libcore.os.
}
// BEGIN Android-removed: Android doesn't need to call native init.
/**
* Perform class load-time initializations.
*
private static native void init();
*/
// END Android-removed: Android doesn't need to call native init.
/*
* Returns the InetAddress representing anyLocalAddress
* (typically 0.0.0.0 or ::0)
*/
static InetAddress anyLocalAddress() {
return impl.anyLocalAddress();
}
// BEGIN Android-removed: Android doesn't load user-provided implementation.
/*
* Load and instantiate an underlying impl class
*
static InetAddressImpl loadImpl(String implName) {
Object impl = null;
/*
* 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", ""));
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 (InetAddressImpl) impl;
}
*/
// END Android-removed: Android doesn't load user-provided implementation.
private void readObjectNoData (ObjectInputStream s) throws
IOException, ClassNotFoundException {
// Android-changed: Don't use null to mean the boot classloader.
if (getClass().getClassLoader() != BOOT_CLASSLOADER) {
throw new SecurityException ("invalid address type");
}
}
// Android-changed: Don't use null to mean the boot classloader.
private static final ClassLoader BOOT_CLASSLOADER = Object.class.getClassLoader();
private void readObject (ObjectInputStream s) throws
IOException, ClassNotFoundException {
// Android-changed: Don't use null to mean the boot classloader.
if (getClass().getClassLoader() != BOOT_CLASSLOADER) {
throw new SecurityException ("invalid address type");
}
GetField gf = s.readFields();
String host = (String)gf.get("hostName", null);
int address= gf.get("address", 0);
int family= gf.get("family", 0);
holder = new InetAddressHolder(host, address, family);
}
/* needed because the serializable fields no longer exist */
/**
* @serialField hostName String
* @serialField address int
* @serialField family int
*/
private static final ObjectStreamField[] serialPersistentFields = {
new ObjectStreamField("hostName", String.class),
new ObjectStreamField("address", int.class),
new ObjectStreamField("family", int.class),
};
private void writeObject (ObjectOutputStream s) throws
IOException {
// Android-changed: Don't use null to mean the boot classloader.
if (getClass().getClassLoader() != BOOT_CLASSLOADER) {
throw new SecurityException ("invalid address type");
}
PutField pf = s.putFields();
pf.put("hostName", holder().hostName);
pf.put("address", holder().address);
pf.put("family", holder().family);
s.writeFields();
s.flush();
}
static final int NETID_UNSET = 0;
// BEGIN Android-added: Add methods required by frameworks/base.
// Particularly those required to deal with scope ids.
/**
* Returns true if the string is a valid numeric IPv4 or IPv6 address (such as "192.168.0.1").
*
*
This copes with all forms of address that Java supports, detailed in the
* {@link InetAddress} class documentation. An empty string is not treated as numeric.
*
* @hide used by frameworks/base to ensure that a getAllByName won't cause a DNS lookup.
* @deprecated Use {@link InetAddressUtils#isNumericAddress(String)} instead, if possible.
* @throws NullPointerException if the {@code address} is {@code null}.
*/
@Deprecated
public static boolean isNumeric(String address) {
return InetAddressUtils.parseNumericAddressNoThrowStripOptionalBrackets(address) != null;
}
/**
* Returns an InetAddress corresponding to the given numeric address (such
* as {@code "192.168.0.1"} or {@code "2001:4860:800d::68"}).
*
*
This method will never do a DNS lookup. Non-numeric addresses are errors. Passing either
* an empty string or a {@code null} as the {@code numericAddress} will return the
* {@link Inet6Address#LOOPBACK} address.
*
* @hide used by frameworks/base's NetworkUtils.numericToInetAddress
* @throws IllegalArgumentException if {@code numericAddress} is not a numeric address
* @deprecated Use {@link InetAddressUtils#parseNumericAddress(String)} instead, if possible.
*/
@Deprecated
public static InetAddress parseNumericAddress(String numericAddress) {
if (numericAddress == null || numericAddress.isEmpty()) {
return Inet6Address.LOOPBACK;
}
InetAddress result = InetAddressUtils
.parseNumericAddressNoThrowStripOptionalBrackets(numericAddress);
if (result == null) {
throw new IllegalArgumentException("Not a numeric address: " + numericAddress);
}
return result;
}
/**
* Removes all entries from the VM's DNS cache. This does not affect the C library's DNS
* cache, nor any caching DNS servers between you and the canonical server.
* @hide
*/
public static void clearDnsCache() {
impl.clearAddressCache();
}
// END Android-added: Add methods required by frameworks/base.
// BEGIN Android-added: Support for network (netId)-specific DNS resolution.
/**
* Operates identically to {@code getByName} except host resolution is
* performed on the network designated by {@code netId}.
*
* @param host
* the hostName to be resolved to an address or {@code null}.
* @param netId the network to use for host resolution.
* @return the {@code InetAddress} instance representing the host.
* @throws UnknownHostException if the address lookup fails.
* @hide
*/
public static InetAddress getByNameOnNet(String host, int netId) throws UnknownHostException {
return impl.lookupAllHostAddr(host, netId)[0];
}
/**
* Operates identically to {@code getAllByName} except host resolution is
* performed on the network designated by {@code netId}.
*
* @param host the hostname or literal IP string to be resolved.
* @param netId the network to use for host resolution.
* @return the array of addresses associated with the specified host.
* @throws UnknownHostException if the address lookup fails.
* @hide
*/
public static InetAddress[] getAllByNameOnNet(String host, int netId) throws UnknownHostException {
return impl.lookupAllHostAddr(host, netId).clone();
}
// END Android-added: Support for network (netId)-specific DNS resolution.
}
// BEGIN Android-removed: Android doesn't load user-provided implementation.
/*
* Simple factory to create the impl
*
class InetAddressImplFactory {
static InetAddressImpl create() {
return InetAddress.loadImpl(isIPv6Supported() ?
"Inet6AddressImpl" : "Inet4AddressImpl");
}
static native boolean isIPv6Supported();
}
*/
// END Android-removed: Android doesn't load user-provided implementation.