#!/usr/bin/perl
#
# create a template for /etc/bootptab
# read logfile and create entry for each MAC address
#   tested with bootpd version 2.4.3 
# bootpd needs option -d4
# use ctrl-c to stop
#
# Copyright (C) 1999  August Hoerandl (hoerandl@elina.htlw1.ac.at)
#                     http://elina.htlw1.ac.at/~hoerandl
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program 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 for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.


# change to fit your needs

# where to write the new entries
$file="bootptab.new";

#where to read
$log="/var/log/messages";
#$log="bootp.log";

# subnet
$subnet="192.168.1";

# first free ip/name - to be incremented
$num=100;
$name="a";

#hostname  
$host="pc409";

#template
$template=".$host";

# type of hostname created
#   $host\$name -> pca, pcb, pcc, ...
#   $host\$num  -> pc1, pc2, pc3, pc4, ...
$fullname="$host\$name";

# full line for bootptab
# use vars from above + $mac
# use \$ for the changing values 

$line="$fullname:ha=\$mac:ip=$subnet.\$num:tc=$template:";

# no user serviceable parts below

# first read all mac addr. already known

open(FILE, "$file") || die "can't open $file: $!\n";

while(<FILE>) {
  next unless /[Hh][Aa]=([0-9a-fA-F]{12,12})/;
  $mac=$1;
  print "found mac $mac\n";
  $macs{$mac}++;
}

close (FILE) || die "can't close $file: $!\n";

# now read the log 
#
open(INPUT, "$log") || die "can't open $log: $!\n";
while (1) {
  while (<INPUT>) {
    next unless /bootpd/;
#    print;
    if (/([0-9a-fA-F][0-9a-fA-F]):([0-9a-fA-F][0-9a-fA-F]):([0-9a-fA-F][0-9a-fA-F]):([0-9a-fA-F][0-9a-fA-F]):([0-9a-fA-F][0-9a-fA-F]):([0-9a-fA-F][0-9a-fA-F])/ ) {
      $mac="$1$2$3$4$5$6";
      print;
      if (! $macs{$mac} ) {
	$macs{$mac}++;
	open(FILE, ">>$file") || die "can't open $file: $!\n";
	eval "print \"\a$line\n\a\"";
	eval "print FILE \"$line\n\"";
	close(FILE)|| die "can't close $file: $!\n";
	$num++;
	$name++;
      }
    }
  }
  sleep(2);
  seek(INPUT, 0, 1);
}