2fa algorithm

function randomString(length, chars) {
    var result = '';
    for (var i = length; i > 0; --i) result += chars[Math.floor(Math.random() * chars.length)];
    return result;
}
var rString = randomString(32, '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ');
console.log(rString);

$value = 'hwefwkZ4tHCfQ425HNtp5ffl7FRVOMND';
$output = '';
for($x = 0; $x < 6; $x++){
$randomnumber = rand(1,32);
$randomelement = substr($value, $randomnumber,1);
$integervalue = ord($randomelement);
$output .= substr($integervalue, -1);
}

echo $output;