#!/usr/bin/perl -w
## Perl script interfaces with robtex.com to gather reverse IP data
##Will accept domain/IP as input
## usage 
## ./robtex.pl google.com
## Updated on 10/14/2010

use LWP::Simple;
use LWP::UserAgent;
use Data::Dumper;


my $input = $ARGV[0];
my $url ='http://www.robtex.com/ip/';

my $ua = new LWP::UserAgent;
$ua->agent("Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1");


my $ns = "/usr/bin/nslookup";


if ($input =~ m/([\d\.]{7,})/){
        my $req = new HTTP::Request GET => ($url.$input.'.rss');
        my $res = $ua->request($req);
        my $robtex = $res->content;
        print "\n\n"."Fetching Domains for"."\n".$input."\n\n";
        if (defined $robtex){

        if ($robtex =~ m/\<span\sid\=\"sharedha\"\>Host\snames\ssharing\sIP\swith\sA\srecords\s(\(.*?\))\<\/span\>/g){
                print "Host names sharing IP with A records $1\n\n";
        }

        if ($robtex =~ m/<span\s+id\=\"sharedha\">(.*?)\<\/div\>/ism ) {
                $sharedDomains = $1;
                while($sharedDomains =~ m/<a\s+href\=\"\/dns\/.*?\.html\#shared\"\s+>(.*?)<\/a>/ig ){
                        print $1."\n";
                }
        }
}

}
elsif ($input !~ m/([\d\.]{7,})/){
        $ns .= " " . $input;
        $rs = `$ns`;
        if ($rs =~ m/Address\:\s+([\d\.]{7,})\s/){
                print "\n$input resolves to $1\n\n";
                my $req = new HTTP::Request GET => ($url.$1.'.rss');
                my $res = $ua->request($req);
                my $robtex = $res->content;
        if (defined $robtex){

        if ($robtex =~ m/\<span\sid\=\"sharedha\"\>Host\snames\ssharing\sIP\swith\sA\srecords\s(\(.*?\))\<\/span\>/g){
                print "Host names sharing IP with A records $1\n\n";
        }

        if ($robtex =~ m/\<span\s+id\=\"sharedha\"\>(.*?)\<\/div\>/ism ) {
                $sharedDomains = $1;
                while($sharedDomains =~ m/<a\s+href\=\"\/dns\/.*?\.html\#shared\"\s+>(.*?)<\/a>/ig ){
                        print $1."\n";
                }
        }
}

        }
}