Bizarre decimal number to in-addr-arpa mapping......

[Farid Hamjavar]

On Wed, 2 Jun 1999, Farid Hamjavar wrote:

> Date: Wed, 2 Jun 1999 12:33:35 -0600
> From: Farid Hamjavar <hamjavar at unm.edu>
> To: Michael Fenton <mfenton at fentonnet.com>
> Cc: comp-protocols-dns-bind at moderators.uu.net,
     Ruth Anne Ladue <Ruth_Anne_Ladue at iengines.net>, bind-users at isc.org
> Newsgroups: comp.protocols.dns.bind
> Subject: Re: Bizarre decimal number to in-addr-arpa mapping......
> 
> On Wed, 2 Jun 1999, Michael Fenton wrote:
> 
> > Date: Wed, 02 Jun 1999 11:33:33 -0500
> > From: Michael Fenton <mfenton at fentonnet.com>
> > To: comp-protocols-dns-bind at moderators.uu.net
> > Newsgroups: comp.protocols.dns.bind
> > Subject: Bizarre decimal number to in-addr-arpa mapping......
> > Resent-Date: Wed, 2 Jun 1999 11:06:42 -0700 (PDT)
> > Resent-From: Ruth Anne Ladue <Ruth_Anne_Ladue at iengines.net>
> > Resent-To: bind-users at isc.org
> > 
> > I discovered that people on my network are getting around
> > our web filtering by using decimal number URL's.
> > Check this out:
> > gunk:~$ nslookup 3489040081
> > Server:  server.tt.net
> > Address:  209.98.124.2
> > 
> > Name:    teen-space.com
> > Address:  207.246.134.209
> > 
> > How the hell does 3489040081 resolve?
> > I did a little looking and it seems to map somehow
> > to an inaddr-arpa address......
> > 
> > Anybody know what's going on here?
> > 
> > Thanks,
> > Michael Fenton
> > 
> 
> 

I forgot the script ....


----8<--------------------------CUT------------------------------->8----
#!/usr/local/gnu/bin/perl
#################################################
#created by hamjavar: Fri Feb  5 12:43:59 MST 1999
#
# This script converts dotted format IP addresses
# into their decimal integer representation.
#
# For example these should all function the same:
#  http://www.sgi.com/
#  http://3626020507/
#  http://216.32.174.155/
#
#
#
#
#################################################
use Socket;
#
$[=1;
$all_digit=0;
$dotted=0;
#
#
#################################################
#Decide which way to go:
if    ($ARGV[0] =~ /^[0-9]+$/)
      {
        $input0 = $ARGV[0];
        $all_digit=1;
        print "#Input is all digits: \"$input0\"\n";
      }
elsif ($ARGV[0] =~ /^[0-9]+.*[0-9]+$/)
      {
        $input0 = $ARGV[0];
        $dotted=1;
        print "#Input is in dotted notation: \"$input0\"\n";
      }
else
      {
       print "Examples:\n";
       $scrloc=`basename $0`;
       chop $scrloc;
       print "$scrloc 3488253803 \n";
       print "$scrloc 207.234.135.107 \n";
       exit 1;
      }
#################################################
#
#
#
#Process according to format of input:
#
if    ($all_digit == 1 )
      {
       $packed_addy = pack('N', $input0);
       $answer = inet_ntoa($packed_addy);
       print "#Answer in dotted form: $answer \n";
      }
#
#
#
#
elsif ($dotted == 1)
      {
       @octet_array = split(/\./,$input0);
       #
       $num_octet=0;
       foreach $octet (@octet_array) {$num_octet++;}
       #
       #print "$num_octet \n";
       $octet_index=1;
       $this_power=$num_octet;
       $sum = 0;
       while ($octet_index  <= $num_octet)
           {
            $this_octet = @octet_array[$octet_index] ;
            $this_power--;
            $x = 256 ** $this_power ;
            $y = $this_octet * $x ;
            $sum = $sum + $y;
            print "#OctetIndex[$octet_index] is  $this_octet  and $this_octet x $x  = $y \n";
            $octet_index++;
           }
            print "#\n#Answer is in decimal $sum \n";
            $hexvalue = sprintf("%lx", $sum) ;
            print "#Answer is in hex is $hexvalue \n"
      }

#
#
#
#
else
      {
       ;
      }
   
#
#
#
#
#
#
#
#
#
#