/* jcifs smb client library in Java
* Copyright (C) 2000 "Michael B. Allen" <jcifs at samba dot org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package com.knowgate.jcifs.netbios;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.HashMap;
import com.knowgate.jcifs.Config;
import com.knowgate.misc.Gadgets;
/**
* This class represents a NetBIOS over TCP/IP address. Under normal
* conditions, users of jCIFS need not be concerned with this class as
* name resolution and session services are handled internally by the smb package.
*
* <p> Applications can use the methods <code>getLocalHost</code>,
* <code>getByName</code>, and
* <code>getAllByAddress</code> to create a new NbtAddress instance. This
* class is symmetric with {@link java.net.InetAddress}.
*
* <p><b>About NetBIOS:</b> The NetBIOS name
* service is a dynamic distributed service that allows hosts to resolve
* names by broadcasting a query, directing queries to a server such as
* Samba or WINS. NetBIOS is currently the primary networking layer for
* providing name service, datagram service, and session service to the
* Microsoft Windows platform. A NetBIOS name can be 15 characters long
* and hosts usually registers several names on the network. From a
* Windows command prompt you can see
* what names a host registers with the nbtstat command.
* <p><blockquote><pre>
* C:\>nbtstat -a 192.168.1.15
*
* NetBIOS Remote Machine Name Table
*
* Name Type Status
* ---------------------------------------------
* JMORRIS2 <00> UNIQUE Registered
* BILLING-NY <00> GROUP Registered
* JMORRIS2 <03> UNIQUE Registered
* JMORRIS2 <20> UNIQUE Registered
* BILLING-NY <1E> GROUP Registered
* JMORRIS <03> UNIQUE Registered
*
* MAC Address = 00-B0-34-21-FA-3B
* </blockquote></pre>
* <p> The hostname of this machine is <code>JMORRIS2</code>. It is
* a member of the group(a.k.a workgroup and domain) <code>BILLING-NY</code>. To
* obtain an {@link java.net.InetAddress} for a host one might do:
*
* <pre>
* InetAddress addr = NbtAddress.getByName( "jmorris2" ).getInetAddress();
* </pre>
* <p>From a UNIX platform with Samba installed you can perform similar
* diagnostics using the <code>nmblookup</code> utility.
*
* @author Michael B. Allen
* @see java.net.InetAddress
* @since jcifs-0.1
*/
public final class NbtAddress {
/*
* This is a special name that means all hosts. If you wish to find all hosts
* on a network querying a workgroup group name is the preferred method.
*/
static final String ANY_HOSTS_NAME = "*\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000";
/**
* This is a special name for querying the master browser that serves the
* list of hosts found in "Network Neighborhood".
*/
public static final String MASTER_BROWSER_NAME = "\u0001\u0002__MSBROWSE__\u0002";
/**
* A special generic name specified when connecting to a host for which
* a name is not known. Not all servers respond to this name.
*/
public static final String SMBSERVER_NAME = "*SMBSERVER ";
/**
* A B node only broadcasts name queries. This is the default if a
* nameserver such as WINS or Samba is not specified.
*/
public static final int B_NODE = 0;
/**
* A Point-to-Point node, or P node, unicasts queries to a nameserver
* only. Natrually the <code>jcifs.netbios.nameserver</code> property must
* be set.
*/
public static final int P_NODE = 1;
/**
* Try Broadcast queries first, then try to resolve the name using the
* nameserver.
*/
public static final int M_NODE = 2;
/**
* A Hybrid node tries to resolve a name using the nameserver first. If
* that fails use the broadcast address. This is the default if a nameserver
* is provided. This is the behavior of Microsoft Windows machines.
*/
public static final int H_NODE = 3;
static final InetAddress[] NBNS = Config.getInetAddressArray( "jcifs.netbios.wins", ",", new InetAddress[0] );
/* Construct the shared static client object that will
* conduct all encoding and decoding of NetBIOS name service
* messages as well as socket IO in a synchronized fashon.
*/
private static final NameServiceClient CLIENT = new NameServiceClient();
private static final int DEFAULT_CACHE_POLICY = 30;
private static final int CACHE_POLICY = Config.getInt( "jcifs.netbios.cachePolicy", DEFAULT_CACHE_POLICY );
private static final int FOREVER = -1;
private static int nbnsIndex = 0;
private static final HashMap ADDRESS_CACHE = new HashMap();
private static final HashMap LOOKUP_TABLE = new HashMap();
static final Name UNKNOWN_NAME = new Name( "0.0.0.0", 0x00, null );
static final NbtAddress UNKNOWN_ADDRESS = new NbtAddress( UNKNOWN_NAME, 0, false, B_NODE );
static final byte[] UNKNOWN_MAC_ADDRESS = new byte[] {
(byte)0x00, (byte)0x00, (byte)0x00,
(byte)0x00, (byte)0x00, (byte)0x00
};
static final class CacheEntry {
Name hostName;
NbtAddress address;
long expiration;
CacheEntry( Name hostName, NbtAddress address, long expiration ) {
this.hostName = hostName;
this.address = address;
this.expiration = expiration;
}
}
static NbtAddress localhost;
static {
InetAddress localInetAddress;
String localHostname;
Name localName;
/* Create an address to represent failed lookups and cache forever.
*/
ADDRESS_CACHE.put( UNKNOWN_NAME, new CacheEntry( UNKNOWN_NAME, UNKNOWN_ADDRESS, FOREVER ));
/* Determine the InetAddress of the local interface
* if one was not specified.
*/
localInetAddress = CLIENT.laddr;
if( localInetAddress == null ) {
try {
localInetAddress = InetAddress.getLocalHost();
} catch( UnknownHostException uhe ) {
}
}
/* If a local hostname was not provided a name like
* JCIFS34_172_A6 will be dynamically generated for the
* client. This is primarily (exclusively?) used as a
* CallingName during session establishment.
*/
localHostname = Config.getProperty( "jcifs.netbios.hostname", null );
if( localHostname == null || localHostname.length() == 0 ) {
byte[] addr = localInetAddress.getAddress();
localHostname = "JCIFS" +
( addr[2] & 0xFF ) + "_" +
( addr[3] & 0xFF ) + "_" +
Gadgets.toHexString( (int)( Math.random() * (double)0xFF ), 2 );
}
/* Create an NbtAddress for the local interface with
* the name deduced above possibly with scope applied and
* cache it forever.
*/
localName = new Name( localHostname, 0x00,
Config.getProperty( "jcifs.netbios.scope", null ));
localhost = new NbtAddress( localName,
localInetAddress.hashCode(),
false,
B_NODE,
false, false, true, false,
UNKNOWN_MAC_ADDRESS );
cacheAddress( localName, localhost, FOREVER );
}
static void cacheAddress( Name hostName, NbtAddress addr ) {
if( CACHE_POLICY == 0 ) {
return;
}
long expiration = -1;
if( CACHE_POLICY != FOREVER ) {
expiration = System.currentTimeMillis() + CACHE_POLICY * 1000;
}
cacheAddress( hostName, addr, expiration );
}
static void cacheAddress( Name hostName, NbtAddress addr, long expiration ) {
if( CACHE_POLICY == 0 ) {
return;
}
synchronized( ADDRESS_CACHE ) {
CacheEntry entry = (CacheEntry)ADDRESS_CACHE.get( hostName );
if( entry == null ) {
entry = new CacheEntry( hostName, addr, expiration );
ADDRESS_CACHE.put( hostName, entry );
} else {
entry.address = addr;
entry.expiration = expiration;
}
}
}
static void cacheAddressArray( NbtAddress[] addrs ) {
if( CACHE_POLICY == 0 ) {
return;
}
long expiration = -1;
if( CACHE_POLICY != FOREVER ) {
expiration = System.currentTimeMillis() + CACHE_POLICY * 1000;
}
synchronized( ADDRESS_CACHE ) {
for( int i = 0; i < addrs.length; i++ ) {
CacheEntry entry = (CacheEntry)ADDRESS_CACHE.get( addrs[i].hostName );
if( entry == null ) {
entry = new CacheEntry( addrs[i].hostName, addrs[i], expiration );
ADDRESS_CACHE.put( addrs[i].hostName, entry );
} else {
entry.address = addrs[i];
entry.expiration = expiration;
}
}
}
}
static NbtAddress getCachedAddress( Name hostName ) {
if( CACHE_POLICY == 0 ) {
return null;
}
synchronized( ADDRESS_CACHE ) {
CacheEntry entry = (CacheEntry)ADDRESS_CACHE.get( hostName );
if( entry != null && entry.expiration < System.currentTimeMillis() &&
entry.expiration >= 0 ) {
entry = null;
}
return entry != null ? entry.address : null;
}
}
static NbtAddress doNameQuery( Name name, InetAddress svr )
throws UnknownHostException {
NbtAddress addr;
if( name.hexCode == 0x1d && svr == null ) {
svr = CLIENT.baddr; // bit of a hack but saves a lookup
}
name.srcHashCode = svr != null ? svr.hashCode() : 0;
addr = getCachedAddress( name );
if( addr == null ) {
/* This was copied amost verbatim from InetAddress.java. See the
* comments there for a description of how the LOOKUP_TABLE prevents
* redundant queries from going out on the wire.
*/
if(( addr = (NbtAddress)checkLookupTable( name )) == null ) {
try {
addr = CLIENT.getByName( name, svr );
} catch( UnknownHostException uhe ) {
addr = UNKNOWN_ADDRESS;
} finally {
cacheAddress( name, addr );
updateLookupTable( name );
}
}
}
if( addr == UNKNOWN_ADDRESS ) {
throw new UnknownHostException( name.toString() );
}
return addr;
}
private static Object checkLookupTable( Name name ) {
Object obj;
synchronized( LOOKUP_TABLE ) {
if( LOOKUP_TABLE.containsKey( name ) == false ) {
LOOKUP_TABLE.put( name, name );
return null;
}
while( LOOKUP_TABLE.containsKey( name )) {
try {
LOOKUP_TABLE.wait();
} catch( InterruptedException e ) {
}
}
}
obj = getCachedAddress( name );
if( obj == null ) {
synchronized( LOOKUP_TABLE ) {
LOOKUP_TABLE.put( name, name );
}
}
return obj;
}
private static void updateLookupTable( Name name ) {
synchronized( LOOKUP_TABLE ) {
LOOKUP_TABLE.remove( name );
LOOKUP_TABLE.notifyAll();
}
}
/**
* Retrieves the local host address.
*
* @throws UnknownHostException This is not likely as the IP returned
* by <code>InetAddress</code> should be available
*/
public static NbtAddress getLocalHost() throws UnknownHostException {
return localhost;
}
/**
* Determines the address of a host given it's host name. The name can be a NetBIOS name like
* "freto" or an IP address like "192.168.1.15". It cannot be a DNS name;
* the analygous {@link jcifs.UniAddress} or {@link java.net.InetAddress}
* <code>getByName</code> methods can be used for that.
*
* @param host hostname to resolve
* @throws java.net.UnknownHostException if there is an error resolving the name
*/
public static NbtAddress getByName( String host )
throws UnknownHostException {
return getByName( host, 0x00, null );
}
/**
* Determines the address of a host given it's host name. NetBIOS
* names also have a <code>type</code>. Types(aka Hex Codes)
* are used to distiquish the various services on a host. <a
* href="../../../nbtcodes.html">Here</a> is
* a fairly complete list of NetBIOS hex codes. Scope is not used but is
* still functional in other NetBIOS products and so for completeness it has been
* implemented. A <code>scope</code> of <code>null</code> or <code>""</code>
* signifies no scope.
*
* @param host the name to resolve
* @param type the hex code of the name
* @param scope the scope of the name
* @throws java.net.UnknownHostException if there is an error resolving the name
*/
public static NbtAddress getByName( String host,
int type,
String scope )
throws UnknownHostException {
return getByName( host, type, scope, null );
}
/*
* The additional <code>svr</code> parameter specifies the address to
* query. This might be the address of a specific host, a name server,
* or a broadcast address.
*/
public static NbtAddress getByName( String host,
int type,
String scope,
InetAddress svr )
throws UnknownHostException {
if( host == null || host.length() == 0 ) {
return getLocalHost();
}
if( !Character.isDigit( host.charAt(0) )) {
return (NbtAddress)doNameQuery( new Name( host, type, scope ), svr );
} else {
int IP = 0x00;
int hitDots = 0;
char[] data = host.toCharArray();
for( int i = 0; i < data.length; i++ ) {
char c = data[i];
if( c < 48 || c > 57 ) {
return (NbtAddress)doNameQuery( new Name( host, type, scope ), svr );
}
int b = 0x00;
while( c != '.' ) {
if( c < 48 || c > 57 ) {
return (NbtAddress)doNameQuery( new Name( host, type, scope ), svr );
}
b = b * 10 + c - '0';
if( ++i >= data.length )
break;
c = data[i];
}
if( b > 0xFF ) {
return (NbtAddress)doNameQuery( new Name( host, type, scope ), svr );
}
IP = ( IP << 8 ) + b;
hitDots++;
}
if( hitDots != 4 || host.endsWith( "." )) {
return (NbtAddress)doNameQuery( new Name( host, type, scope ), svr );
}
return new NbtAddress( UNKNOWN_NAME, IP, false, B_NODE );
}
}
/**
* Retrieve all addresses of a host by it's address. NetBIOS hosts can
* have many names for a given IP address. The name and IP address make the
* NetBIOS address. This provides a way to retrieve the other names for a
* host with the same IP address.
*
* @param host hostname to lookup all addresses for
* @throws java.net.UnknownHostException if there is an error resolving the name
*/
public static NbtAddress[] getAllByAddress( String host )
throws UnknownHostException {
return getAllByAddress( getByName( host, 0x00, null ));
}
/**
* Retrieve all addresses of a host by it's address. NetBIOS hosts can
* have many names for a given IP address. The name and IP address make
* the NetBIOS address. This provides a way to retrieve the other names
* for a host with the same IP address. See {@link #getByName}
* for a description of <code>type</code>
* and <code>scope</code>.
*
* @param host hostname to lookup all addresses for
* @param type the hexcode of the name
* @param scope the scope of the name
* @throws java.net.UnknownHostException if there is an error resolving the name
*/
public static NbtAddress[] getAllByAddress( String host,
int type,
String scope )
throws UnknownHostException {
return getAllByAddress( getByName( host, type, scope ));
}
/**
* Retrieve all addresses of a host by it's address. NetBIOS hosts can
* have many names for a given IP address. The name and IP address make the
* NetBIOS address. This provides a way to retrieve the other names for a
* host with the same IP address.
*
* @param addr the address to query
* @throws UnknownHostException if address cannot be resolved
*/
public static NbtAddress[] getAllByAddress( NbtAddress addr )
throws UnknownHostException {
try {
NbtAddress[] addrs = CLIENT.getNodeStatus( addr );
cacheAddressArray( addrs );
return addrs;
} catch( UnknownHostException uhe ) {
throw new UnknownHostException( "no name with type 0x" +
Gadgets.toHexString( addr.hostName.hexCode, 2 ) +
((( addr.hostName.scope == null ) ||
( addr.hostName.scope.length() == 0 )) ?
" with no scope" : " with scope " + addr.hostName.scope ) +
" for host " + addr.getHostAddress() );
}
}
public static InetAddress getWINSAddress() {
return NBNS.length == 0 ? null : NBNS[nbnsIndex];
}
public static boolean isWINS( InetAddress svr ) {
for( int i = 0; svr != null && i < NBNS.length; i++ ) {
if( svr.hashCode() == NBNS[i].hashCode() ) {
return true;
}
}
return false;
}
static InetAddress switchWINS() {
nbnsIndex = (nbnsIndex + 1) < NBNS.length ? nbnsIndex + 1 : 0;
return NBNS.length == 0 ? null : NBNS[nbnsIndex];
}
Name hostName;
int address, nodeType;
boolean groupName,
isBeingDeleted,
isInConflict,
isActive,
isPermanent,
isDataFromNodeStatus;
byte[] macAddress;
String calledName;
NbtAddress( Name hostName, int address, boolean groupName, int nodeType ) {
this.hostName = hostName;
this.address = address;
this.groupName = groupName;
this.nodeType = nodeType;
}
NbtAddress( Name hostName,
int address,
boolean groupName,
int nodeType,
boolean isBeingDeleted,
boolean isInConflict,
boolean isActive,
boolean isPermanent,
byte[] macAddress ) {
/* The NodeStatusResponse.readNodeNameArray method may also set this
* information. These two places where node status data is populated should
* be consistent. Be carefull!
*/
this.hostName = hostName;
this.address = address;
this.groupName = groupName;
this.nodeType = nodeType;
this.isBeingDeleted = isBeingDeleted;
this.isInConflict = isInConflict;
this.isActive = isActive;
this.isPermanent = isPermanent;
this.macAddress = macAddress;
isDataFromNodeStatus = true;
}
/* Guess next called name to try for session establishment. These
* methods are used by the smb package.
*/
public String firstCalledName() {
calledName = hostName.name;
if( Character.isDigit( calledName.charAt( 0 ))) {
int i, len, dots;
char[] data;
i = dots = 0; /* quick IP address validation */
len = calledName.length();
data = calledName.toCharArray();
while( i < len && Character.isDigit( data[i++] )) {
if( i == len && dots == 3 ) {
// probably an IP address
calledName = SMBSERVER_NAME;
break;
}
if( i < len && data[i] == '.' ) {
dots++;
i++;
}
}
} else if( hostName.hexCode == 0x1D ) {
calledName = SMBSERVER_NAME;
}
return calledName;
}
public String nextCalledName() {
if( calledName == hostName.name ) {
calledName = SMBSERVER_NAME;
} else if( calledName == SMBSERVER_NAME ) {
NbtAddress[] addrs;
try {
addrs = CLIENT.getNodeStatus( this );
if( hostName.hexCode == 0x1D ) {
for( int i = 0; i < addrs.length; i++ ) {
if( addrs[i].hostName.hexCode == 0x20 ) {
return addrs[i].hostName.name;
}
}
return null;
} else if( isDataFromNodeStatus ) {
/* 'this' has been updated and should now
* have a real NetBIOS name
*/
calledName = null;
return hostName.name;
}
} catch( UnknownHostException uhe ) {
calledName = null;
}
} else {
calledName = null;
}
return calledName;
}
/*
* There are three degrees of state that any NbtAddress can have.
*
* 1) IP Address - If a dot-quad IP string is used with getByName (or used
* to create an NbtAddress internal to this netbios package), no query is
* sent on the wire and the only state this object has is it's IP address
* (but that's enough to connect to a host using *SMBSERVER for CallingName).
*
* 2) IP Address, NetBIOS name, nodeType, groupName - If however a
* legal NetBIOS name string is used a name query request will retreive
* the IP, node type, and whether or not this NbtAddress represents a
* group name. This degree of state can be obtained with a Name Query
* Request or Node Status Request.
*
* 3) All - The NbtAddress will be populated with all state such as mac
* address, isPermanent, isBeingDeleted, ...etc. This information can only
* be retrieved with the Node Status request.
*
* The degree of state that an NbtAddress has is dependant on how it was
* created and what is required of it. The second degree of state is the
* most common. This is the state information that would be retrieved from
* WINS for example. Natrually it is not practical for every NbtAddress
* to be populated will all state requiring a Node Status on every host
* encountered. The below methods allow state to be populated when requested
* in a lazy fashon.
*/
void checkData() throws UnknownHostException {
if( hostName == UNKNOWN_NAME ) {
getAllByAddress( this );
}
}
void checkNodeStatusData() throws UnknownHostException {
if( isDataFromNodeStatus == false ) {
getAllByAddress( this );
}
}
/**
* Determines if the address is a group address. This is also
* known as a workgroup name or group name.
*
* @throws UnknownHostException if the host cannot be resolved to find out.
*/
public boolean isGroupAddress() throws UnknownHostException {
checkData();
return groupName;
}
/**
* Checks the node type of this address.
* @return {@link jcifs.netbios.NbtAddress#B_NODE},
* {@link jcifs.netbios.NbtAddress#P_NODE}, {@link jcifs.netbios.NbtAddress#M_NODE},
* {@link jcifs.netbios.NbtAddress#H_NODE}
*
* @throws UnknownHostException if the host cannot be resolved to find out.
*/
public int getNodeType() throws UnknownHostException {
checkData();
return nodeType;
}
/**
* Determines if this address in the process of being deleted.
*
* @throws UnknownHostException if the host cannot be resolved to find out.
*/
public boolean isBeingDeleted() throws UnknownHostException {
checkNodeStatusData();
return isBeingDeleted;
}
/**
* Determines if this address in conflict with another address.
*
* @throws UnknownHostException if the host cannot be resolved to find out.
*/
public boolean isInConflict() throws UnknownHostException {
checkNodeStatusData();
return isInConflict;
}
/**
* Determines if this address is active.
*
* @throws UnknownHostException if the host cannot be resolved to find out.
*/
public boolean isActive() throws UnknownHostException {
checkNodeStatusData();
return isActive;
}
/**
* Determines if this address is set to be permanent.
*
* @throws UnknownHostException if the host cannot be resolved to find out.
*/
public boolean isPermanent() throws UnknownHostException {
checkNodeStatusData();
return isPermanent;
}
/**
* Retrieves the MAC address of the remote network interface. Samba returns all zeros.
*
* @return the MAC address as an array of six bytes
* @throws UnknownHostException if the host cannot be resolved to
* determine the MAC address.
*/
public byte[] getMacAddress() throws UnknownHostException {
checkNodeStatusData();
return macAddress;
}
/**
* The hostname of this address. If the hostname is null the local machines
* IP address is returned.
*
* @return the text representation of the hostname associated with this address
*/
public String getHostName() {
try {
checkData();
} catch( UnknownHostException uhe ) {
return getHostAddress();
}
return hostName.name;
}
/**
* Returns the raw IP address of this NbtAddress. The result is in network
* byte order: the highest order byte of the address is in getAddress()[0].
*
* @return a four byte array
*/
public byte[] getAddress() {
byte[] addr = new byte[4];
addr[0] = (byte)(( address >>> 24 ) & 0xFF );
addr[1] = (byte)(( address >>> 16 ) & 0xFF );
addr[2] = (byte)(( address >>> 8 ) & 0xFF );
addr[3] = (byte)( address & 0xFF );
return addr;
}
/**
* To convert this address to an <code>InetAddress</code>.
*
* @return the {@link java.net.InetAddress} representation of this address.
*/
public InetAddress getInetAddress() throws UnknownHostException {
return InetAddress.getByName( getHostAddress() );
}
/**
* Returns this IP adress as a {@link java.lang.String} in the form "%d.%d.%d.%d".
*/
public String getHostAddress() {
return (( address >>> 24 ) & 0xFF ) + "." +
(( address >>> 16 ) & 0xFF ) + "." +
(( address >>> 8 ) & 0xFF ) + "." +
(( address >>> 0 ) & 0xFF );
}
/**
* Returned the hex code associated with this name(e.g. 0x20 is for the file service)
*/
public int getNameType() {
return hostName.hexCode;
}
/**
* Returns a hashcode for this IP address. The hashcode comes from the IP address
* and is not generated from the string representation. So because NetBIOS nodes
* can have many names, all names associated with an IP will have the same
* hashcode.
*/
public int hashCode() {
return address;
}
/**
* Determines if this address is equal two another. Only the IP Addresses
* are compared. Similar to the {@link #hashCode} method, the comparison
* is based on the integer IP address and not the string representation.
*/
public boolean equals( Object obj ) {
return ( obj != null ) && ( obj instanceof NbtAddress ) &&
( ((NbtAddress)obj).address == address );
}
/**
* Returns the {@link java.lang.String} representaion of this address.
*/
public String toString() {
return hostName.toString() + "/" + getHostAddress();
}
}