#!/usr/bin/perl
#
# Prints info on all smb responding machines on a subnet.
# This script needs to be run on a machine without nmbd running and be
# run as root to get correct info from WIN95 clients.
#
# syntax:
#    findsmb [subnet broadcast address]
#
# with no agrument it will list machines on the current subnet
#
# There will be a "+" in front of the workgroup name for machines that are
# local master browsers for that workgroup. There will be an "*" in front
# of the workgroup name for machines that are the domain master browser for
# that workgroup.
#

$SAMBABIN = "/usr/bin";

for ($i = 0; $i < 2; $i++) {	# test for -d option and broadcast address
  $_ = shift;
  if (m/-d|-D/) {
    $DEBUG = 1;
  } else  {
    if ($_) {
      $BCAST = "-B $_";
    }
  }
}

sub ipsort			# do numeric sort on last field of IP address
{
  @t1 = split(/\./,$a);
  @t2 = split(/\./,$b);
  @t1[3] <=> @t2[3];
}

# look for all machines that respond to a name lookup

open(NMBLOOKUP,"$SAMBABIN/nmblookup $BCAST '*'|") || 
  die("Can't run nmblookup '*'.\n");

# get rid of all lines that are not a response IP address,
# strip everything but IP address and sort by last field in address

@ipaddrs = sort ipsort grep(s/ \*<00>.*$//,<NMBLOOKUP>);

# print header info

print "\n                                *=DMB\n";
print "                                +=LMB\n";
print "IP ADDR         NETBIOS NAME     WORKGROUP/OS/VERSION $BCAST\n";
print "---------------------------------------------------------------------\n";

foreach $ip (@ipaddrs)		# loop through each IP address found
{
  $ip =~ s/\n//;		# strip newline from IP address

# find the netbios names registered by each machine

  open(NMBLOOKUP,"$SAMBABIN/nmblookup -r -A $ip|") || 
	die("Can't get nmb name list.\n");
  @nmblookup = <NMBLOOKUP>;
  close NMBLOOKUP;

# get the first non group <00> name

  @name = grep(/<00> -        /,@nmblookup);
  $_ = @name[0];
  if (not $_) {
# try without the -r option
    open(NMBLOOKUP,"$SAMBABIN/nmblookup -A $ip|") ||
        die("Can't get nmb name list.\n");
    @nmblookup = <NMBLOOKUP>;
    close NMBLOOKUP;
    @name = grep(/<00> -        /,@nmblookup);
    $_ = @name[0];
  }
# The Netbios name can contain lot of characters also '<' '>'
# and spaces. The follwing cures embedded space but not
# names starting or ending with spaces
  /(.{1,15})\s+<00>\s+/;
  $name = $1;

  if (not $name) {                     # no netbios name found
# try getting the host name
    ($name, $aliases, $type, $length, @addresses) = 
      gethostbyaddr(pack('C4',split('\.',$ip)),2);
    if (! $name) {			# could not get name
      $name = "unknown name";
    }
# truncate name to 15 characters
    if (length($name) > 15) {
        $name = substr($name,0,15);
    }
# do an smbclient command on the ip address

    open(SMB,"$SAMBABIN/smbclient -N -L '$ip' -I $ip -U% |") ||
        die("Can't do smbclient command.\n");
    @smb = <SMB>;
    close SMB;
  } else {                              # netbios name found

# do an smbclient command on the netbios name.

    open(SMB,"$SAMBABIN/smbclient -N -L '$name' -I $ip -U% |") ||
	die("Can't do smbclient command.\n");
    @smb = <SMB>;
    close SMB;
  }
  if ($DEBUG) {		# if -d flag print results of nmblookup and smbclient
    print "===============================================================\n";
    print @nmblookup;
    print @smb;
  }

# look for the OS= string

  @info = grep(/OS=/,@smb);
  $_ = @info[0];
  if ($_) {				# we found response
    s/.*Domain=|OS=|Server=|\n//g;	# strip out descriptions to make line shorter

  } else {				# no OS= string in response (WIN95 client)

# for WIN95 clients get workgroup name from nmblookup response
    @name = grep(/<00> - <GROUP>/,@nmblookup);
    $_ = @name[0];
    if ($_) {
# Same as before for space and characters
      /(.{1,15})\s+<00>\s+/;
      $_ = "[$1]";
    } else {
      $_ = "Unknown Workgroup";
    }
  }

# see if machine registered a local master browser name
  if (grep(/<1d>/,@nmblookup)) {
    $master = '+';			# indicate local master browser
    if (grep(/<1b>/,@nmblookup)) {	# how about domain master browser?
      $master = '*';			# indicate domain master browser
    }
  } else {
    $master = ' ';			# not a browse master
  }

# line up info in 3 columns

  print "$ip".' 'x(16-length($ip))."$name".' 'x(16-length($name))."$master"."$_\n";

} 

