#!@PERL@
# Convert IP address to domain mappings from a DB file
# into an Analog DNS cache file.
# The DB file was produced by dns-terror.
# Output is to stdout, which should be saved in the file dns.cache
# and sourced in Analog config files with:
# DNS READ
# DNSFILE dns.cache
# # 1008 is (35+7)*24, one week past the expire-ip-db default.
# DNSGOODHOURS 1008
# DNSBADHOURS 1008
#
# Written by Chris Ross <cross@distal.com>
# and David MacKenzie <djm@djmnet.org>
# Please send comments and bug reports to <fastresolve-bugs@djmnet.org>

##############################################################################
#   Copyright 1999 UUNET, an MCI WorldCom company.
#
# 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, 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., 59 Temple Place - Suite 330, Boston, MA
# 02111-1307, USA.
##############################################################################

use BerkeleyDB;
use Fcntl;

main();
exit(0);

sub main
{
    my(%input, $dbfile, $timestamp, $timecode, $ipaddr, $domain);

    $dbfile = shift @ARGV || "ip2host.db";

    tie(%input, "BerkeleyDB::Btree", -Filename => $dbfile, -Flags => DB_RDONLY)
	|| die "$0: Can't read $dbfile: $!\n";
    
    while (($ipaddr, $domain) = each(%input)) {
	($timestamp, $domain) = unpack("IA*", $domain);

	$domain ||= "*";

	# We write the timecode in GMT, which the next release of
	# Analog will do, too.  Being a few hours off doesn't matter,
	# anyway; it's just used for expiring old entries.
	$timecode = int(($timestamp / 60) + (24 * 60));
	print "$timecode $ipaddr $domain\n";
    }
    
    untie(%input);
}