#!/usr/bin/perl
# Read IP addresses from first field of Apache logfile and determine country

use strict;
use Net::DNS;

my $domain = "qupps.geo";
my $res   = Net::DNS::Resolver->new(            # create resolver object
        nameservers => [qw(127.0.0.3)] );

my ($ip, $rev, $query);
my %ipcache;                                    # cache identical IP
my %countrylist;                                # count countries

while (<>) {
        chomp;
        s/\s.*$//;                              # leaves only IP

        if (defined($ipcache{$ip = $_})) {
                $countrylist{$ipcache{$ip}}++;  # IP seen; incr.counter
                next;
        }

        my ($a, $b, $c, $d) = split(/\./, $_, 4);
        $rev = "$d.$c.$b.$a.$domain";

        $query = $res->search($rev, 'TXT');     # perform query
        if ($query) {
                my $rr = ($query->answer)[0];
                if ($rr->type eq 'TXT') {
                        $ipcache{$ip} = $rr->txtdata;
                        $countrylist{$rr->txtdata}++;
                }
        } else {
                warn "query $rev failed: ", $res->errorstring, "\n";
        }
}
foreach my $country (keys %countrylist) {
        print $countrylist{$country} . " " . $country . "\n";
}