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NAME

Net::DNSBL::Monitor - Monitor DNSBL response

SYNOPSIS

run
plaintxt
htmltxt
plainresp
htmlresp
);
($dnsblcnts,$responses)=run(\%config,$NonBlockSock,$sockaddr_in);
$text = plaintxt(\%config,\%dnsblcnts);
$html = htmltxt(\%config,\%dnsblnts);
$text = plainresp(\%responses);
$html = htmlresp(\$config,\%responses);

DESCRIPTION

Net::DNSBL::Monitor is the Perl module that can be used to check when ranges of IP addresses have been blacklisted. Net::DNSBL::Monitor generates a statistical report for the DNSBL's interrogated and provides an individual report for each IP address found in a DNSBL. The module is used to implement the reporting script dnsblmon.

CONFIGURATION FILE

With the addition of a few elements, the configuration file for dnsblmon shares a common format with the Mail::SpamCannibal sc_BLcheck.pl script, and Net::DNSBL::Statistics config file, facilitating common maintenance of DNSBL's for your MTA installation.

The sample configuration file monitor.conf.sample is heavily commented with the details for each configuration element.

A useful list of DNSBL zones for the config file (put together by "Andrey V. Stolyarov" <croco-gnu@openwall.com>) maybe found in the contrib directory zones4config.file.

SYSTEM SIGNALS

dnsblmon responds to the following system signals:

  • TERM

    Script is terminated.

PERL MODULE DESCRIPTION - Script Implementation

Net::DNSBL::Monitor provides most of the functions that implement dnsblmon which is a script that collects statistics and responses for a list of IP address interrogated against a list of DNSBL's

dnsblmon usage

How to use dnsblmon

Syntax: dnsblmon path/to/config.file or dnsblmon -t path/to/config.file dnsblmon -w path/to/config.file

dnsblmon path/to/config.file -r -s
dnsblmon path/to/config.file -s -r
dnsblmon path/to/config.file \
-r path/outfile1 \
-s path/outfile2

Normally dnsblmon prints an IP report sorted by "comment" and IP of the DNSBL's interrogated with their reply results for each IP address.

The 'comment' field may contain html markup text.

i.e. commenta
1.2.3.4 127.0.0.3 zen.spamhaus.org
127.0.0.5 dnsbl.sorbs.net
1.2.3.5 127.0.0.5 dnsbl.sorbs.net
commentb
3.4.5.6 127.0.0.2 bl.spamcannibal.org

With the (-s) switch, dnsblmon prints a sorted list (by count) of the DNSBL's interrogated with their reply count, percentage of the total count, and any comments from the DNSBL's 'comment' key field in the config file.

The 'comment' field may contain html markup text.

i.e.
44 100.0% TOTAL IP's interrogated
41 93.2% UNION of all results
34 77.3% dnsbl.sorbs.net comment
........

The -t switch will print a start and stop time to STDOUT

i.e.
# start: Fri Jan 4 17:46:44 2008
# stop : Fri Jan 4 17:58:21 2008

The -w switch will put the output into an HTML table without the <table> statement </table>., a commment as above and with an <a href="...">dnsbl name</a> statement replacing the dnsbl name if the 'url' key is present in the config file.

The -r and -s switchs are position dependent output designators.

-r REPORT output designator
-s STATISTICS output designator
as follows:
-r -s would produce the report on STDOUT and the statistics
on STDERR.
-s -r would produce the statistics on STDOUT and the
report on STDERR.
-s outfile1 -r outfile2 would write the statistics and report
to outfile1 and outfile2 respectively.

Other combinations are possible. Switches are order dependent but not positionally dependent with respect to other switches

dnsblmon input file format

The input file format for dnsblmon consists of an address element block in the form used by NetAddr::IP followed by a 'comment field'. The report generated will be sorted on the 'comment field', then by IP address.

i.e. input format
1.2.3.4 single host IP belonging to XYZ
2.3.4.5/24 A class C belonging to ABC hosting
etc...

Net::DNSBL::Monitor FUNCTIONS

  • ($dnsblcnts,$responses)=run(\%config,$NonBlockSock,$sockaddr_in);

    Returns the total number of IP's interrogated (IP list less white listed items) and a hash of DNSBL names and their respective SPAM reply counts or equivalent for 'in-addr.arpa' and GENERIC.

    input: config pointer,
    non-blocking socket descriptor,
    sockaddr_in for local DNS host
    returns: pointer to dnsbl count hash
    pointer to response hash

    The dnsbl count hash will have two added keys:

    TOTAL the total number of interrogations less whitelist
    UNION the total number of spam 'hits'

    The response hash will be of the form:

    $response = {
    '1.2.3.4' => {
    'COMMENT' => 'text from comment field for IP range',
    'bl.xyz.com' => '127.0.0.2',
    'bl.abc.net' => '127.0.0.5',
    },
    etc...
    };
    HINTs: use Net::NBsocket qw( open_udbNB sockaddr_in );
    use Net::DNS::ToolKit qw( get_ns );
    my $sock = open_udpNB();
    my $sockaddr_in = sockaddr_in(53, scalar get_ns());
  • $text = plaintxt($config,\%dnsbls);

    Generate a plain text report of the form:

    44 100.0% TOTAL IP's interrogated
    41 93.2% UNION of all results
    34 77.3% dnsbl.sorbs.net comment
    22 50.0% GENERIC comment
    13 29.5% in-addr.arpa comment
    11 25.0% cbl.abuseat.org comment
    9 20.5% list.dsbl.org comment
    2 4.5% dnsbl.njabl.org comment
    1 2.3% bl.spamcannibal.org comment
    0 0.0% dynablock.njabl.org comment
    input: configuration pointer,
    dnsbl count hash pointer
    returns: text buffer

    The 'comment' comes from the config file 'comment' key field for each specified DNSBL or is blank if there is no 'comment' key.

  • $html = htmltxt($config,\%dnsbls);

    Generate a report as above but with <tr><td></td></tr> table markup. The <table></table> tags are not generated. If there is a 'url' key field in the respective DNSBL config entry, the DNSBL name is provide with <a href="url">DNSBL</a> tags with the specified 'url' as the 'href' value.

    input: configuration pointer,
    dnsbl count hash pointer
    returns: html text buffer

    A one line example corresponding to the text line above:

    34 77.3% dnsbl.sorbs.net
    with a 'comment' key of: 127.0.0.2,5,7,8,9,10,12
    <tr class=dnsbl><td align=right>34</td>
    <td align=right>77.3%</td>
    <td align=left><a
    href="http://www.au.sorbs.net/using.shtml">dnsbl.sorbs.net</a></td>
    <td align=left>127.0.0.2,5,7,8,9,10,12</td>
    </tr>
  • $text = plainresp(\%response);

    Generate a plain text report of the form:

    comment string 1
    ipaddr1 response code dnsbl
    response code dnsbl
    response code dnsbl
    ipaddr2 response code dnsbl
    comment string 2
    ipaddr3 response code dnsbl
    etc...
    input: response hash pointer
    returns: text buffer
  • $html = htmlresp(\%config,\%response);

    Generate a report as above but with <tr><td></td></tr> table markup. The <table></table> tags are not generated.

    input: config hash pointer
    response hash pointer
    returns: html text buffer

    A one line example corresponding to the text line above:

    34 77.3% dnsbl.sorbs.net
    with a 'comment' key of: 127.0.0.2,5,7,8,9,10,12
    <tr class=dnsbl><td align=right>34</td>
    <td align=right>77.3%</td>
    <td align=left><a
    href="http://www.au.sorbs.net/using.shtml">dnsbl.sorbs.net</a></td>
    <td align=left>127.0.0.2,5,7,8,9,10,12</td>
    </tr>

Monitor Web Page HOWTO

Read the contrib/HOWTO document that describes the scripts used with 'cron' to auto generate web pages for the statistics reports

EXPORT_OK

run
plaintxt
htmltxt
plainresp
htmlresp

AUTHOR

Michael Robinton, michael@bizsystems.com

COPYRIGHT

Copyright 2008-2014, Michael Robinton. 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

SEE ALSO

Mail::SpamCannibal, Net::DNS::Codes, Net::DNS::ToolKit, Net::DNSBL::MultiDaemon NetAddr::IP