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Net::NBName(3)	      User Contributed Perl Documentation	Net::NBName(3)

NAME
       Net::NBName - NetBIOS Name Service Requests

SYNOPSIS
	 use Net::NBName;
	 my $nb	= Net::NBName->new;

	 # a unicast node status request
	 my $ns	= $nb->node_status("10.0.0.1");
	 if ($ns) {
	     print $ns->as_string;
	 }

	 # a unicast name query	request
	 my $nq	= $nb->name_query("10.0.1.80", "SPARK",	0x00);
	 if ($nq) {
	     print $nq->as_string;
	 }

	 # a broadcast name query request
	 my $nq	= $nb->name_query(undef, "SPARK", 0x00);
	 if ($nq) {
	     print $nq->as_string;
	 }

DESCRIPTION
       Net::NBName is a	class that allows you to perform simple	NetBIOS	Name
       Service Requests	in your	Perl code. It performs these NetBIOS
       operations over TCP/IP using Perl's built-in socket support.

       I've currently implemented two NBNS requests: the node status request
       and the name query request.

       NetBIOS Node Status Request
	   This	allows you to determine	the registered NetBIOS names for a
	   specified remote host.

	   The decoded response	is returned as a "Net::NBName::NodeStatus"
	   object.

	       querying	192.168.0.10 for node status...
	       SPARK	      <20> UNIQUE M-node Registered Active
	       SPARK	      <00> UNIQUE M-node Registered Active
	       PLAYGROUND     <00> GROUP  M-node Registered Active
	       PLAYGROUND     <1C> GROUP  M-node Registered Active
	       PLAYGROUND     <1B> UNIQUE M-node Registered Active
	       PLAYGROUND     <1E> GROUP  M-node Registered Active
	       SPARK	      <03> UNIQUE M-node Registered Active
	       PLAYGROUND     <1D> UNIQUE M-node Registered Active
	       ..__MSBROWSE__.<01> GROUP  M-node Registered Active
	       MAC Address = 00-1C-2B-3A-49-58

       NetBIOS Name Query Request
	   This	allows you to resolve a	name to	an IP address using NetBIOS
	   Name	Resolution. These requests can either be unicast (e.g. if you
	   are querying	an NBNS	server)	or broadcast on	the local subnet.

	   In either case, the decoded response	is returned as an
	   "Net::NBName::NameQuery" object.

	       querying	192.168.0.10 for playground<00>...
	       255.255.255.255 GROUP  B-node
	       ttl = 0 (default	is 300000)
	       RA set, this was	an NBNS	server

	       broadcasting for	playground<1C>...
	       192.168.0.10    GROUP  B-node
	       ttl = 0 (default	is 300000)
	       RA set, this was	an NBNS	server

	       broadcasting for	spark<20>...
	       192.168.0.10    UNIQUE H-node
	       ttl = 0 (default	is 300000)
	       RA set, this was	an NBNS	server

CONSTRUCTOR
       $nb = Net::NBName->new
	   Creates a new "Net::NBName" object. This can	be used	to perform
	   NetBIOS Name	Service	requests.

METHODS
       $ns = $nb->node_status( $host [,	$timeout] )
	   This	will query the host for	its node status. The response will be
	   returned as a "Net::NBName::NodeStatus" object.

	   If no response is received from the host, the method	will return
	   undef.

	   You can also	optionally specify the timeout in seconds for the node
	   status request. The timeout defaults	to .25 seconds.

       $nq = $nb->name_query( $host, $name, $suffix [, $flags [, $timeout] ] )
	   This	will query the host for	the specified name. The	response will
	   be returned as a "Net::NBName::NameQuery" object.

	   If $host is undef, then a broadcast name query will be performed;
	   otherwise, a	unicast	name query will	be performed.

	   Broadcast name queries can sometimes	receive	multiple responses.
	   Only	the first positive response will be decoded and	returned as a
	   "Net::NBName::NameQuery" object.

	   If no response is received or a negative name query response	is
	   received, the method	will return undef.

	   You can override the	flags in the NetBIOS name request, if you
	   *really* want to. See the notes on Hacking Name Query Flags.

	   You can also	optionally specify the timeout in seconds for the name
	   query request. It defaults to .25 seconds for unicast name queries
	   and 1 second	for broadcast name queries.

EXAMPLES
   Querying NetBIOS Names
       You can use this	example	to query for a NetBIOS name. If	you specify a
       host, it	will perform a unicast query; if you don't specify a host, it
       will perform a broadcast	query. I've used the shorthand of specifying
       the name	as <name>#<suffix> where the suffix should be in hex.

       "namequery.pl spark#0"

       "namequery.pl spark#20 192.168.0.10"

	   use strict;
	   use Net::NBName;

	   my $nb = Net::NBName->new;
	   my $param = shift;
	   my $host = shift;
	   if ($param =~ /^([\w-]+)\#(\w{1,2})$/) {
	       my $name	= $1;
	       my $suffix = hex	$2;

	       my $nq;
	       if (defined($host) && $host =~ /\d+\.\d+\.\d+\.\d+/) {
		   printf "querying %s for %s<%02X>...\n", $host, $name, $suffix;
		   $nq = $nb->name_query($host,	$name, $suffix);
	       } else {
		   printf "broadcasting	for %s<%02X>...\n", $name, $suffix;
		   $nq = $nb->name_query(undef,	$name, $suffix);
	       }
	       if ($nq)	{
		   print $nq->as_string;
	       }
	   } else {
	       die "expected: <name>#<suffix> [<host>]\n";
	   }

   Querying Remote Name	Table
       This example emulates the windows nbtstat -A command. By	specifying the
       ip address of the remote	host, you can check its	NetBIOS	Name Table.

       "nodestat.pl 192.168.0.10"

	   use Net::NBName;

	   my $nb = Net::NBName->new;
	   my $host = shift;
	   if (defined($host) && $host =~ /\d+\.\d+\.\d+\.\d+/)	{
	       my $ns =	$nb->node_status($host);
	       if ($ns)	{
		   print $ns->as_string;
	       } else {
		   print "no response\n";
	       }
	   } else {
	       die "expected: <host>\n";
	   }

   Scanning for	NetBIOS	hosts
       This example can	be used	to scan	for NetBIOS hosts on a subnet. It uses
       Net::Netmask to parse the subnet	parameter and enumerate	the hosts in
       that subnet.

       "nodescan.pl 192.168.0.0/24"

	   use Net::NBName;
	   use Net::Netmask;

	   $mask = shift or die	"expected: <subnet>\n";

	   $nb = Net::NBName->new;
	   $subnet = Net::Netmask->new2($mask);
	   for $ip ($subnet->enumerate)	{
	       print "$ip ";
	       $ns = $nb->node_status($ip);
	       if ($ns)	{
		   for my $rr ($ns->names) {
		       if ($rr->suffix == 0 && $rr->G eq "GROUP") {
			   $domain = $rr->name;
		       }
		       if ($rr->suffix == 3 && $rr->G eq "UNIQUE") {
			   $user = $rr->name;
		       }
		       if ($rr->suffix == 0 && $rr->G eq "UNIQUE") {
			   $machine = $rr->name	unless $rr->name =~ /^IS~/;
		       }
		   }
		   $mac_address	= $ns->mac_address;
		   print "$mac_address $domain\\$machine $user";
	       }
	       print "\n";
	   }

NOTES
   Microsoft's WINS Server Implementation
       When performing name queries, you should	note that when Microsoft
       implemented their NBNS Name Server (Microsoft WINS Server) they mapped
       group names to the single IP address 255.255.255.255 (the limited
       broadcast address). In order to support real group names, Microsoft
       modified	WINS to	provide	support	for special groups. These groups
       appear differently in WINS. For example,	the Domain Controllers (0x1C)
       group appears as	"Domain	Name" instead of "Group".

       The complete set	of WINS	mapping	types is:

	   Unique
	   Group
	   Domain Name
	   Internet group
	   Multihomed

       Unique and Group	map to a single	IP address. Domain Name, Internet
       group, and Multihomed are special groups	that can include up to 25 IP
       addresses.

   Hacking Name	Query Flags
       NetBIOS Name Service Requests have a number of flags associated with
       them.  These are	set to sensible	defaults by the	code when sending node
       status and name query requests.

       However,	it is possible to override these settings by calling the
       name_query method of a "Net::NBName" object with	a fourth parameter:

	   $nb->name_query( $host, $name, $suffix, $flags );

       For a unicast name query, the flags default to 0x0100 which sets	the RD
       (recursion desired) flag. For a broadcast name query, the flags default
       to 0x0010 which sets the	B (broadcast) flag.

       Experimentation gave the	following results:

       o   If B	is set,	the remote name	table will be used. There will be no
	   response if the queried name	is not present.

       o   If B	is not set and the host	is an NBNS server, the NBNS server
	   will	be used	before the remote name table and you will get a
	   negative response if	the name is not	present; if the	host is	not an
	   NBNS	server,	you will get no	response if the	name is	not present.

COPYRIGHT
       Copyright (c) 2002, 2003, 2004 James Macfarlane.	All rights reserved.
       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

perl v5.24.1			  2006-06-26			Net::NBName(3)

NAME | SYNOPSIS | DESCRIPTION | CONSTRUCTOR | METHODS | EXAMPLES | NOTES | COPYRIGHT

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