AWS IP address ranges scanner

amazon-ip-ranges.pl

#!/usr/bin/env perl
use strict;
use warnings qw(all);

use constant IP_RANGES_JSON => 'https://ip-ranges.amazonaws.com/ip-ranges.json';

use JSON::PP qw();
use LWP::Simple qw();
use NetAddr::IP qw();

my $needle = NetAddr::IP->new($ARGV[0] || '127.0.0.1');

my $json = JSON::PP->new
    ->ascii
    ->canonical
    ->pretty
;

my $filename = IP_RANGES_JSON;
$filename =~ s{^.*/}{};

my $status = LWP::Simple::mirror(IP_RANGES_JSON, $filename);
die "HTTP status $status when downloading @{[ IP_RANGES_JSON ]}\n"
    if $status ne 200 && $status ne 304;

my $ip_ranges = do {
    local $/;
    open(my $fh, '<', $filename) || die "Can't read $filename: $@\n";
    $json->decode(<$fh>);
};

for my $prefix ($ip_ranges->{prefixes}->@*) {
    my $haystack = NetAddr::IP->new($prefix->{ip_prefix});
    if ($needle->within($haystack)) {
        print $json->encode($prefix);
        last;
    }
}

exit 0;