session_handler_redirect.php

<?php
/**
 * 
 */
ob_start();


class EncryptedSessionHandler extends SessionHandler
{

    protected $ttl = 5;

    use Base62Encoder;
    use OpenSSLEncrypter;

    public function __construct($key)
    {
        $this->key = $key;
    }

    public function read($id)
    {
        $id = $this->checkId($id);
        var_dump([__FUNCTION__, $id]);
        if (!$id) {
            return false;
        }
        return parent::read($id);
    }

    public function write($id, $data)
    {
        $id = $this->checkId($id);
        var_dump([__FUNCTION__, $id]);
        return parent::write($id, $data);
    }

    public function destroy($id)
    {
        var_dump([__FUNCTION__, $id]);
        // parent::destroy($key);
    }

    public function create_sid() 
    {
        $id = [uniqid(true), isset($_SERVER['HTTP_USER_AGENT']) ? substr($_SERVER['HTTP_USER_AGENT'], 0, 100) : null, time()];
        return $this->encrypt($id);
    }


    protected function checkId($id)
    {
        $uac = isset($_SERVER['HTTP_USER_AGENT']) ? substr($_SERVER['HTTP_USER_AGENT'], 0, 100) : null;
        list($key, $ua, $mtime) = $this->decrypt($id);
        if ($mtime < time() - $this->ttl) {
            return null;
        }
        if ($ua !== $uac) {
            return null;
        }
        return $key;
    }


}

trait OpenSSLEncrypter
{
    protected $key;
    protected $cipherMethod = "aes-256-cbc";

    /**
     * [encrypt description]
     * @param  [type] $decrypted [description]
     * @return [type]            [description]
     */
    public function encrypt($decrypted)
    {
        $iv = openssl_random_pseudo_bytes(openssl_cipher_iv_length($this->cipherMethod));
        $encrypted = openssl_encrypt(serialize($decrypted), $this->cipherMethod, $this->key, 0, $iv);
        $data = join(':', [$this->cipherMethod, base64_encode($iv), base64_encode($encrypted)]);
        return $this->encode($data);
    }

    public function decrypt($encrypted)
    {
        list($algo, $iv, $encrypted) = explode(':', $this->decode($encrypted));
        $decrypted = openssl_decrypt(base64_decode($encrypted), $algo, $this->key, 0, base64_decode($iv));
        return unserialize($decrypted);
    }

}


trait Base62Encoder
{

    protected $chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";

    public function encode($data)
    {
        if (is_integer($data)) {
            $data = [$data];
        } else {
            $data = str_split($data);
            $data = array_map(function ($character) {
                return ord($character);
            }, $data);
        }
        $converted = $this->baseConvert($data, 256, 62);
        return implode("", array_map(function ($index) {
            return $this->chars[$index];
        }, $converted));
    }
    public function decode($data, $integer = false)
    {
        $data = str_split($data);
        $data = array_map(function ($character) {
            return strpos($this->chars, $character);
        }, $data);
        /* Return as integer when requested. */
        if ($integer) {
            $converted = $this->baseConvert($data, 62, 10);
            return (integer) implode("", $converted);
        }
        $converted = $this->baseConvert($data, 62, 256);
        return implode("", array_map(function ($ascii) {
            return chr($ascii);
        }, $converted));
    }

    public function baseConvert(array $source, $source_base, $target_base)
    {
        $result = [];
        while ($count = count($source)) {
            $quotient = [];
            $remainder = 0;
            for ($i = 0; $i !== $count; $i++) {
                $accumulator = $source[$i] + $remainder * $source_base;
                $digit = (integer) ($accumulator / $target_base);
                $remainder = $accumulator % $target_base;
                if (count($quotient) || $digit) {
                    array_push($quotient, $digit);
                };
            }
            array_unshift($result, $remainder);
            $source = $quotient;
        }
        return $result;
    }
}


session_set_save_handler(new EncryptedSessionHandler('tututu'));


session_start();

if (@$_GET['sleep']) {
    sleep(max($_GET['sleep'], 5));
}

// $i = 0;
// while ($sessid = @$_SESSION['regenid']) {
//     session_abort();
//     session_write_close();
//     if ($sessid == session_id()) {
//         $_SESSION['regenid'] = null;
//         break;
//     }
//     var_dump([$sessid, session_id(), @$_SESSION['regenid']]);
//     session_id($_SESSION['regenid']);
//     session_start();
//     var_dump([session_id()]);
//     var_dump([$sessid, session_id(), @$_SESSION['regenid']]);
//     if (++$i > 10) break;
// }

$_SESSION['count'] = @$_SESSION['count']+1;
print date(DATE_COOKIE) . ' — ' . session_id() . ' — ' . $_SESSION['count'];

session_regenerate_id();


if (!array_key_exists('sleep', $_GET)) {
    ?>

    <script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>
    <script src="http://cdn.intercoolerjs.org/intercooler-1.1.1.min.js"></script>

    <hr/>
    <div ic-get-from="?sleep=1" ic-trigger-on="load"></div>
    <hr/>
    <div ic-get-from="?sleep=1" ic-trigger-on="load" ic-trigger-delay="500ms"></div>
    <hr/>
    <div ic-get-from="?sleep=3" ic-trigger-on="load"></div>

    <?php 

}