<?php

function generarCodigo($longitud) {
 $key = '';
 $pattern = '1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
 $max = strlen($pattern)-1;
 for($i=0;$i < $longitud;$i++) $key .= $pattern{mt_rand(0,$max)};
 return $key;
}
 

$plaintext = 'Hola Mundo';
$password = generarCodigo(32);
$method = 'aes-256-cbc';

$key = password_hash($password, PASSWORD_BCRYPT, ['cost' => 12]);
//echo "Key:" . $key . "<br>";

$iv = rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9) . rand(0,9);


$encrypted = base64_encode(openssl_encrypt($plaintext, $method, $key, OPENSSL_RAW_DATA, $iv));
$decrypted = openssl_decrypt(base64_decode($encrypted), $method, $key, OPENSSL_RAW_DATA, $iv);


echo 'decrypted to: ' . $decrypted . "<br>";
echo $encrypted ."<br>";