--- /home/cpdev/src/classpath/java/net/InetAddress.java 2005-07-02 21:03:35.000000000 +0000 +++ java/net/InetAddress.java 2005-06-30 05:34:40.000000000 +0000 @@ -38,13 +38,13 @@ package java.net; +import gnu.classpath.Configuration; + import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.io.ObjectStreamException; import java.io.Serializable; -import java.util.HashMap; -import java.util.StringTokenizer; /** * This class models an Internet address. It does not have a public @@ -66,94 +66,25 @@ private static final long serialVersionUID = 3286316764910316507L; /** - * The default DNS hash table size, - * Use a prime number happy with hash table. - */ - private static final int DEFAULT_CACHE_SIZE = 89; - - /** - * The default caching period in minutes. - */ - private static final int DEFAULT_CACHE_PERIOD = 4 * 60; - - /** - * Percentage of cache entries to purge when the table gets full. - */ - private static final int DEFAULT_CACHE_PURGE_PCT = 30; - - /** - * The special IP address INADDR_ANY. - */ - private static InetAddress inaddr_any; - - /** * Dummy InetAddress, used to bind socket to any (all) network interfaces. */ static InetAddress ANY_IF; + + private static final byte[] loopbackAddress = { 127, 0, 0, 1 }; - /** - * Stores static localhost address object. - */ - static InetAddress LOCALHOST; - - /** - * The size of the cache. - */ - private static int cache_size = 0; - - /** - * The length of time we will continue to read the address from cache - * before forcing another lookup. - */ - private static int cache_period = 0; - - /** - * What percentage of the cache we will purge if it gets full. - */ - private static int cache_purge_pct = 0; + private static final InetAddress loopback + = new Inet4Address(loopbackAddress, "localhost"); - /** - * HashMap to use as DNS lookup cache. - * Use HashMap because all accesses to cache are already synchronized. - */ - private static HashMap cache; + private static InetAddress localhost = null; static { - // Look for properties that override default caching behavior - cache_size = - Integer.getInteger("gnu.java.net.dns_cache_size", DEFAULT_CACHE_SIZE) - .intValue(); - cache_period = - Integer.getInteger("gnu.java.net.dns_cache_period", - DEFAULT_CACHE_PERIOD * 60 * 1000).intValue(); - - cache_purge_pct = - Integer.getInteger("gnu.java.net.dns_cache_purge_pct", - DEFAULT_CACHE_PURGE_PCT).intValue(); - - // Fallback to defaults if necessary - if ((cache_purge_pct < 1) || (cache_purge_pct > 100)) - cache_purge_pct = DEFAULT_CACHE_PURGE_PCT; - - // Create the cache - if (cache_size != 0) - cache = new HashMap(cache_size); - - // precompute the ANY_IF address - try - { - ANY_IF = getInaddrAny(); - - byte[] ip_localhost = { 127, 0, 0, 1 }; - LOCALHOST = new Inet4Address(ip_localhost, "localhost"); - } - catch (UnknownHostException uhe) - { - // Hmmm, make one up and hope that it works. - byte[] zeros = { 0, 0, 0, 0 }; - ANY_IF = new Inet4Address(zeros, "0.0.0.0"); - } + // load the shared library needed for name resolution + if (Configuration.INIT_LOAD_LIBRARY) + System.loadLibrary("javanet"); + + byte[] zeros = { 0, 0, 0, 0 }; + ANY_IF = new Inet4Address(zeros, "0.0.0.0"); } /** @@ -174,11 +105,6 @@ String hostName; /** - * The time this address was looked up. - */ - transient long lookup_time; - - /** * The field 'family' seems to be the AF_ value. * FIXME: Much of the code in the other java.net classes does not make * use of this family field. A better implementation would be to make @@ -200,9 +126,8 @@ addr = (null == ipaddr) ? null : (byte[]) ipaddr.clone(); hostName = hostname; - lookup_time = System.currentTimeMillis(); - - family = 2; /* AF_INET */ + if (ipaddr != null) + family = getFamily(ipaddr); } /** @@ -220,6 +145,10 @@ if (addr.length == 4) return (addr[0] & 0xf0) == 0xe0; + // Mask against high order bits of 11111111 + if (addr.length == 16) + return addr [0] == (byte) 0xFF; + return false; } @@ -367,15 +296,10 @@ if (hostName != null) return hostName; - try - { - hostName = VMInetAddress.getHostByAddr(addr); - return hostName; - } - catch (UnknownHostException e) - { - return getHostAddress(); - } + // Lookup hostname and set field. + lookup (null, this, false); + + return hostName; } /** @@ -422,6 +346,31 @@ return (byte[]) addr.clone(); } + /* Helper function due to a CNI limitation. */ + private static InetAddress[] allocArray (int count) + { + return new InetAddress [count]; + } + + /* Helper function due to a CNI limitation. */ + private static SecurityException checkConnect (String hostname) + { + SecurityManager s = System.getSecurityManager(); + + if (s == null) + return null; + + try + { + s.checkConnect (hostname, -1); + return null; + } + catch (SecurityException ex) + { + return ex; + } + } + /** * Returns the IP address of this object as a String. The address is in * the dotted octet notation, for example, "127.0.0.1". @@ -437,6 +386,39 @@ int len = addr.length; int i = 0; + if (len == 16) + { // An IPv6 address. + for ( ; ; i += 2) + { + if (i >= 16) + return sb.toString(); + + int x = ((addr [i] & 0xFF) << 8) | (addr [i + 1] & 0xFF); + boolean empty = sb.length() == 0; + + if (empty) + { + if (i == 10 && x == 0xFFFF) + { // IPv4-mapped IPv6 address. + sb.append (":FFFF:"); + break; // Continue as IPv4 address; + } + else if (i == 12) + { // IPv4-compatible IPv6 address. + sb.append (':'); + break; // Continue as IPv4 address. + } + else if (i > 0) + sb.append ("::"); + } + else + sb.append (':'); + + if (x != 0 || i >= 14) + sb.append (Integer.toHexString (x).toUpperCase()); + } + } + for ( ; ; ) { sb.append(addr[i] & 0xff); @@ -565,38 +547,28 @@ * * @param hostname the name of the host */ - private static byte[] aton(String hostname) - { - StringTokenizer st = new StringTokenizer(hostname, "."); - - if (st.countTokens() == 4) - { - int index; - byte[] address = new byte[4]; - - for (index = 0; index < 4; index++) - { - try - { - short n = Short.parseShort(st.nextToken()); - - if ((n < 0) || (n > 255)) - break; + private static native byte[] aton(String hostname); - address[index] = (byte) n; - } - catch (NumberFormatException e) - { - break; - } - } - - if (index == 4) - return address; - } + /** + * Looks up all addresses of a given host. + * + * @param hostname the host to lookup + * @param ipaddr the IP address to lookup + * @param all return all known addresses for one host + * + * @return an array with all found addresses + */ + private static native InetAddress[] lookup (String hostname, + InetAddress ipaddr, boolean all); - return null; - } + /** + * Returns tha family type of an IP address. + * + * @param addr the IP address + * + * @return the family + */ + private static native int getFamily (byte[] ipaddr); /** * Returns an InetAddress object representing the IP address of the given @@ -619,8 +591,42 @@ public static InetAddress getByName(String hostname) throws UnknownHostException { - InetAddress[] addresses = getAllByName(hostname); - return addresses[0]; + // If null or the empty string is supplied, the loopback address + // is returned. Note that this is permitted without a security check. + if (hostname == null || hostname.length() == 0) + return loopback; + + SecurityManager s = System.getSecurityManager(); + if (s != null) + s.checkConnect(hostname, -1); + + // Assume that the host string is an IP address + byte[] address = aton(hostname); + if (address != null) + { + if (address.length == 4) + return new Inet4Address (address, null); + else if (address.length == 16) + { + if ((address [10] == 0xFF) && (address [11] == 0xFF)) + { + byte[] ip4addr = new byte [4]; + ip4addr [0] = address [12]; + ip4addr [1] = address [13]; + ip4addr [2] = address [14]; + ip4addr [3] = address [15]; + return new Inet4Address (ip4addr, null); + } + return new Inet6Address (address, null); + } + else + throw new UnknownHostException ("Address has invalid length"); + } + + // Try to resolve the host by DNS + InetAddress result = new InetAddress(null, null); + lookup (hostname, result, false); + return result; } /** @@ -643,124 +649,37 @@ public static InetAddress[] getAllByName(String hostname) throws UnknownHostException { + // If null or the empty string is supplied, the loopback address + // is returned. Note that this is permitted without a security check. + if (hostname == null || hostname.length() == 0) + return new InetAddress[] {loopback}; + SecurityManager s = System.getSecurityManager(); if (s != null) s.checkConnect(hostname, -1); - InetAddress[] addresses; - - // Default to current host if necessary - if (hostname == null) + // Check if hostname is an IP address + byte[] address = aton (hostname); + if (address != null) { - addresses = new InetAddress[1]; - addresses[0] = LOCALHOST; - return addresses; + InetAddress[] result = new InetAddress [1]; + result [0] = new InetAddress (address, null); + return result; } - // Check the cache for this host before doing a lookup - addresses = checkCacheFor(hostname); - - if (addresses != null) - return addresses; - - // Not in cache, try the lookup - byte[][] iplist = VMInetAddress.getHostByName(hostname); - - if (iplist.length == 0) - throw new UnknownHostException(hostname); - - addresses = new InetAddress[iplist.length]; - - for (int i = 0; i < iplist.length; i++) - { - if (iplist[i].length != 4) - throw new UnknownHostException(hostname); - - addresses[i] = new Inet4Address(iplist[i], hostname); - } - - addToCache(hostname, addresses); - return addresses; + // Try to resolve the hostname by DNS + return lookup (hostname, null, true); } /** - * This method checks the DNS cache to see if we have looked this hostname - * up before. If so, we return the cached addresses unless it has been in the - * cache too long. - * - * @param hostname The hostname to check for + * This native method looks up the hostname of the local machine + * we are on. If the actual hostname cannot be determined, then the + * value "localhost" will be used. This native method wrappers the + * "gethostname" function. * - * @return The InetAddress for this hostname or null if not available + * @return The local hostname. */ - private static synchronized InetAddress[] checkCacheFor(String hostname) - { - InetAddress[] addresses = null; - - if (cache_size == 0) - return null; - - Object obj = cache.get(hostname); - if (obj == null) - return null; - - if (obj instanceof InetAddress[]) - addresses = (InetAddress[]) obj; - - if (addresses == null) - return null; - - if (cache_period != -1) - if ((System.currentTimeMillis() - addresses[0].lookup_time) > cache_period) - { - cache.remove(hostname); - return null; - } - - return addresses; - } - - /** - * This method adds an InetAddress object to our DNS cache. Note that - * if the cache is full, then we run a purge to get rid of old entries. - * This will cause a performance hit, thus applications using lots of - * lookups should set the cache size to be very large. - * - * @param hostname The hostname to cache this address under - * @param obj The InetAddress or InetAddress array to store - */ - private static synchronized void addToCache(String hostname, Object obj) - { - if (cache_size == 0) - return; - - // Check to see if hash table is full - if (cache_size != -1) - if (cache.size() == cache_size) - { - // FIXME Add code to purge later. - } - - cache.put(hostname, obj); - } - - /** - * Returns the special address INADDR_ANY used for binding to a local - * port on all IP addresses hosted by a the local host. - * - * @return An InetAddress object representing INDADDR_ANY - * - * @exception UnknownHostException If an error occurs - */ - static InetAddress getInaddrAny() throws UnknownHostException - { - if (inaddr_any == null) - { - byte[] tmp = VMInetAddress.lookupInaddrAny(); - inaddr_any = new Inet4Address(tmp, null); - } - - return inaddr_any; - } + private static native String getLocalHostname(); /** * Returns an InetAddress object representing the address of the current @@ -773,11 +692,66 @@ */ public static InetAddress getLocalHost() throws UnknownHostException { - String hostname = VMInetAddress.getLocalHostname(); - return getByName(hostname); + SecurityManager s = System.getSecurityManager(); + + // Experimentation shows that JDK1.2 does cache the result. + // However, if there is a security manager, and the cached result + // is other than "localhost", we need to check again. + if (localhost == null + || (s != null && ! localhost.isLoopbackAddress())) + getLocalHost (s); + + return localhost; + } + + private static synchronized void getLocalHost (SecurityManager s) + throws UnknownHostException + { + // Check the localhost cache again, now that we've synchronized. + if (s == null && localhost != null) + return; + + String hostname = getLocalHostname(); + + if (s != null) + { + // "The Java Class Libraries" suggests that if the security + // manager disallows getting the local host name, then + // we use the loopback host. + // However, the JDK 1.2 API claims to throw SecurityException, + // which seems to suggest SecurityException is *not* caught. + // In this case, experimentation shows that former is correct. + try + { + // This is wrong, if the name returned from getLocalHostname() + // is not a fully qualified name. FIXME. + s.checkConnect (hostname, -1); + } + catch (SecurityException ex) + { + hostname = null; + } + } + + if (hostname != null && hostname.length() != 0) + { + try + { + localhost = new InetAddress (null, null); + lookup (hostname, localhost, false); + } + catch (Exception ex) + { + } + } + else + throw new UnknownHostException(); + + if (localhost == null) + localhost = new InetAddress (loopbackAddress, "localhost"); } - /* + /** * Needed for serialization */ private void readResolve() throws ObjectStreamException @@ -795,7 +769,12 @@ for (int i = 2; i >= 0; --i) addr[i] = (byte) (address >>= 8); - family = 2; /* AF_INET */ + // Ignore family from serialized data. Since the saved address is 32 bits + // the deserialized object will have an IPv4 address i.e. AF_INET family. + // FIXME: An alternative is to call the aton method on the deserialized + // hostname to get a new address. The Serialized Form doc is silent + // on how these fields are used. + family = getFamily (addr); } private void writeObject(ObjectOutputStream oos) throws IOException @@ -806,7 +785,7 @@ int i = len - 4; for (; i < len; i++) - address = address << 8 | (addr[i] & 0xff); + address = address << 8 | (((int) addr[i]) & 0xFF); oos.defaultWriteObject(); }