#!/usr/bin/perl
#
# Copyright (c) 2002 TAKANO Yuji <takachan@running-dog.net>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
# dhcpd4named.pl - dhcpd get IP for named of zone-file add.

######################################################################
# モジュール呼び出し
######################################################################

use DBI;

######################################################################
# 初期変数設定
######################################################################

# 逆引きの登録をするかしないかの指定 (YES:登録する/NO:登録しない)
my $RevZone = "YES";

# Cron で設定する時間間隔を "秒" で指定
my $CronTime = 300;

# dhcpd のログを指定 /etc/syslog.conf に以下の様に指定すると便利
# !dhcpd
# *.*             /var/log/dhcpd.log
my $DhcpdLog = '/var/log/dhcpd.log';

# dhcpd.log から拾ってくる文字列パタンの指定
my $LogPat   = 'DHCPACK';

# DHCP で管理するドメインの指定
my $Domain = 'icmpv6.org';

# zone ファイルの TTL を指定
my $TTL    = '3600';



# データベース情報
$Db       = 'DBI:mysql:bind9:localhost';
$Dbuser   = 'bind';
$Dbpasswd = 'bind';

# MySQL テーブル名(正引き)
$Dbtbl_dom_tbl = 'icmpv6_org';

# MySQL テーブル名(逆引き)
$Dbtbl_rev_tbl = '100_168_192_rev';


######################################################################
# コマンドの実行
######################################################################

my $Dbcon    = "";
my $Dbcmd    = "";
my @Dbstatus = "";

# 時間情報の取得
my $time      = time - $CronTime;
my $tmptime   = localtime($time);
my @tmp       = split(" ",$tmptime);
my $StartTime = "$tmp[1] $tmp[2] $tmp[3]"; 

#print "Get Log: $time - " . time . "\n";

$Dbcon = DBI -> connect($Db,$Dbuser,$Dbpasswd);

# ログの読み込み
open(LOG,"<$DhcpdLog");
while(<LOG>) {
    my @tmp = split;
    $Time = "$tmp[0] $tmp[1] $tmp[2]";

# 以前 cron が動作した時間後のログの抽出
    if ($StartTime le $Time) {

#print "Get Log: $StartTime - $Time\n";

	while (<LOG>) {
            if (/${LogPat}.*\((.*).*\).*/) {

# ログから IP アドレスとホスト名を抽出
                my @tmp = split;
	        my $IP = $tmp[7];
	        my ($HostName,@tmp) = split('\.',$1);
		$HostName =~ tr/[A-Z]/[a-z]/;

# DB 更新処理呼び出し
   	        &DB_Write($HostName,$IP);
	    }
        }
    }
}

exit 1;


######################################################################
# DB 書き込み処理
######################################################################

sub DB_Write {
    my $HostName = shift;
    my $IP = shift;

    my @tmp   = split('\.',$IP);
    my $RevIP = "$tmp[3].$tmp[2].$tmp[1].$tmp[0]";

    if ($RevZone =~ /yes/i) {

# 以前有った逆引きの削除
        my $SQL = "DELETE FROM $Dbtbl_rev_tbl WHERE NAME = '$RevIP.in-addr.arpa'";
        $Dbcmd = $Dbcon -> prepare($SQL);
        $Dbcmd -> execute() or &Pal_Error("DELETE 1 ERROR");

# 逆引きテーブルに追加
        my $SQL = "INSERT INTO $Dbtbl_rev_tbl ";
        $SQL   .= "VALUES ('$RevIP.in-addr.arpa','$TTL','PTR','${HostName}.${Domain}.')";
        $Dbcmd = $Dbcon -> prepare($SQL);
        $Dbcmd -> execute() or &Pal_Error("INSERT 1 ERROR");
    }

# 以前有った正引きの削除
    my $SQL = "DELETE FROM $Dbtbl_dom_tbl WHERE RDATA = '$IP'";
    $Dbcmd = $Dbcon -> prepare($SQL);
    $Dbcmd -> execute() or &Pal_Error("DELETE 2 ERROR");

# 以前有った正引きの削除
    my $SQL = "DELETE FROM $Dbtbl_dom_tbl WHERE NAME = '${HostName}.${Domain}'";
    $Dbcmd = $Dbcon -> prepare($SQL);
    $Dbcmd -> execute() or &Pal_Error("DELETE 3 ERROR");

# 正引きテーブルに追加
    my $SQL = "INSERT INTO $Dbtbl_dom_tbl ";
    $SQL   .= "VALUES ('${HostName}.${Domain}','$TTL','A','$IP')";
    $Dbcmd = $Dbcon -> prepare($SQL);
    $Dbcmd -> execute() or &Pal_Error("INSERT 2 ERROR");

    return 0;
}

### エラー出力 ###
sub Pal_Error {
    print $_ . "\n\n";
    exit 1;
}