#!/usr/bin/perl -wT

use strict;

use CGI;
use Email::Valid;


# retrieve form parameter(s)
my $q = new CGI;

my $tainted_email = $q->param("email");

# check that $tainted_email is valid
my $is_valid = Email::Valid->address('$tainted_email');

# if $tainted_email is valid, store the address in $email
my $email = "";

if ($is_valid) {
    $email = $tainted_email;
}

# grab user information
my $ip_address = $ENV{REMOTE_ADDR};
my $referrer   = $ENV{HTTP_REFERER};


if ($email) {
    # store the data in a plain text file
    open LOG, ">>newsletter.txt" or die "Cannot Access Logfile: $!"
    print LOG "$email : $ip_address : $referrer\n";
    close LOG;
}


# print thank-you page