NAME

       Mail::Milter::Module::ConnectMatchesHostname - milter to accept/reject connecting hosts
       matching regex(es)

SYNOPSIS

           use Mail::Milter::Module::ConnectMatchesHostname;

           my $milter = new Mail::Milter::Module::ConnectMatchesHostname;

           my $milter2 = &ConnectMatchesHostname; # convenience

           $milter2->set_message('Connecting hostname %H looks like a dynamic address');

DESCRIPTION

       This milter module rejects any connecting host whose hostname contains one of a group of
       built-in patterns that match the IP address of the connecting host.  This is normally used
       to detect dynamic pool addresses.

       Currently the following patterns embedded in the hostname are considered matching, where
       10.11.12.13 is the IPv4 address of the connecting host.  In the following cases, the
       string must be preceded by a non-digit character or otherwise must be at the start of the
       hostname.

           010.011.012.013. (optionally without internal dots, or with - in place of .)
           013.012.011.010. (optionally with - in place of .)
           10.11.12.13. (optionally without internal dots, or with - in place of .)
           13.12.11.10. (optionally with - in place of .)
           0A0B0C0D (hexadecimal, ignoring case)

       More specific patterns are anticipated to be added in the future.  Because of this, if you
       use ConnectMatchesHostname, pay attention to this perldoc manual page when updating to a
       newer version of Mail::Milter.

       One final note.  ISPs can and do use "dynamic-looking" reverse DNS entries for what they
       consider to be legitimate server addresses.  This is not ideal, and may require embedding
       this module in a Chain set to "accept_break" with regular expressions; for example:

           my $milter = new Mail::Milter::Chain(
               &ConnectRegex(
                   '\.fooisp\.com$',
               )->accept_match(1);
               &ConnectMatchesHostname,
           )->accept_break(1);

METHODS

           new()

           Creates a ConnectMatchesHostname object.

           set_message(MESSAGE)

           Sets the message used when rejecting connections.  This string may contain the
           substring %H, which will be replaced by the matching hostname, and/or the substring
           %A, which will be replaced by the matching IP address.

           This method returns a reference to the object itself, allowing this method call to be
           chained.

BUGS

       In Sendmail 8.11 and 8.12, a milter rejection at "connect" stage does not allow the reply
       message to be set -- it simply becomes "not accepting messages".  However, this module
       still attempts to set the reply code and message in the hope that this will be fixed.

       The implementation of this module could be much more efficient.

AUTHOR

       Todd Vierling, <tv@duh.org> <tv@pobox.com>

SEE ALSO

       Mail::Milter::Object

POD ERRORS

       Hey! The above document had some coding errors, which are explained below:

       Around line 98:
           You can't have =items (as at line 110) unless the first thing after the =over is an
           =item

perl v5.22.2                                2016Mail::Milter::Module::ConnectMatchesHostname(3pm)