Blocks hack attempts against asterisk

ip_blocker.pl

#!/usr/bin/perl -w
use strict;
use warnings;
my (@failhost);
my %currblocked;
my %addblocked;
my $action;
 
open (MYINPUTFILE, "/var/log/asterisk/messages") or die "\n", $!, "Does log file file exist\?\n\n";
 
while (<MYINPUTFILE>) {
    my ($line) = $_;
    chomp($line);
    if ($line =~ m/\' failed for \'(.*?)\' - No matching peer found/) {
        push(@failhost,$1);
    }
    if ($line =~ m/\' failed for \'(.*?)\' – Wrong password/) {
        push(@failhost,$1);
    }
}
 
my $blockedhosts = `iptables -n -L asterisk`;
 
while ($blockedhosts =~ /(.*)/g) {
    my ($line2) = $1;
    chomp($line2);
    if ($line2 =~ m/(\d+\.\d+\.\d+\.\d+)(\s+)/) {
        $currblocked{ $1 } = 'blocked';
    }
}
 
if (@failhost) {
    &count_unique(@failhost);
    while (my ($ip, $count) = each(%addblocked)) {
        if (exists $currblocked{ $ip }) {
            print "$ip already blocked\n";
        } else {
            if ($count >= 10) {
                $action = `iptables -I asterisk -s $ip -j DROP`;
                print "$ip blocked. Failed attempts: $count\n";
            } else {
                print "$ip NOT blocked. Only $count failed attempt(s).\n";
            }
        }
    }
} else {
    print "no failed registrations.\n";
}
 
sub count_unique {
    my @array = @_;
    my %count;
    map { $count{$_}++ } @array;
    map {($addblocked{ $_ } = ${count{$_}})} sort keys(%count);
}