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<?php/** * CodeIgniter * * An open source application development framework for PHP * * This content is released under the MIT License (MIT) * * Copyright (c) 2014 - 2017, British Columbia Institute of Technology * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. * * @package CodeIgniter * @author EllisLab Dev Team * @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/) * @copyright Copyright (c) 2014 - 2017, British Columbia Institute of Technology (http://bcit.ca/) * @license http://opensource.org/licenses/MIT MIT License * @link https://codeigniter.com * @since Version 3.0.0 * @filesource */defined('BASEPATH') OR exit('No direct script access allowed');
/** * CodeIgniter Session Redis Driver * * @package CodeIgniter * @subpackage Libraries * @category Sessions * @author Andrey Andreev * @link https://codeigniter.com/user_guide/libraries/sessions.html */class CI_Session_redis_driver extends CI_Session_driver implements SessionHandlerInterface {
/** * phpRedis instance * * @var Redis */ protected $_redis;
/** * Key prefix * * @var string */ protected $_key_prefix = 'ci_session:';
/** * Lock key * * @var string */ protected $_lock_key;
/** * Key exists flag * * @var bool */ protected $_key_exists = FALSE;
// ------------------------------------------------------------------------
/** * Class constructor * * @param array $params Configuration parameters * @return void */ public function __construct(&$params) { parent::__construct($params);
if (empty($this->_config['save_path'])) { log_message('error', 'Session: No Redis save path configured.'); } elseif (preg_match('#(?:tcp://)?([^:?]+)(?:\:(\d+))?(\?.+)?#', $this->_config['save_path'], $matches)) { isset($matches[3]) OR $matches[3] = ''; // Just to avoid undefined index notices below
$this->_config['save_path'] = array( 'host' => $matches[1], 'port' => empty($matches[2]) ? NULL : $matches[2], 'password' => preg_match('#auth=([^\s&]+)#', $matches[3], $match) ? $match[1] : NULL, 'database' => preg_match('#database=(\d+)#', $matches[3], $match) ? (int) $match[1] : NULL, 'timeout' => preg_match('#timeout=(\d+\.\d+)#', $matches[3], $match) ? (float) $match[1] : NULL );
preg_match('#prefix=([^\s&]+)#', $matches[3], $match) && $this->_key_prefix = $match[1]; } else { log_message('error', 'Session: Invalid Redis save path format: '.$this->_config['save_path']); }
if ($this->_config['match_ip'] === TRUE) { $this->_key_prefix .= $_SERVER['REMOTE_ADDR'].':'; } }
// ------------------------------------------------------------------------
/** * Open * * Sanitizes save_path and initializes connection. * * @param string $save_path Server path * @param string $name Session cookie name, unused * @return bool */ public function open($save_path, $name) { if (empty($this->_config['save_path'])) { return $this->_fail(); }
$redis = new Redis(); if ( ! $redis->connect($this->_config['save_path']['host'], $this->_config['save_path']['port'], $this->_config['save_path']['timeout'])) { log_message('error', 'Session: Unable to connect to Redis with the configured settings.'); } elseif (isset($this->_config['save_path']['password']) && ! $redis->auth($this->_config['save_path']['password'])) { log_message('error', 'Session: Unable to authenticate to Redis instance.'); } elseif (isset($this->_config['save_path']['database']) && ! $redis->select($this->_config['save_path']['database'])) { log_message('error', 'Session: Unable to select Redis database with index '.$this->_config['save_path']['database']); } else { $this->_redis = $redis; return $this->_success; }
return $this->_fail(); }
// ------------------------------------------------------------------------
/** * Read * * Reads session data and acquires a lock * * @param string $session_id Session ID * @return string Serialized session data */ public function read($session_id) { if (isset($this->_redis) && $this->_get_lock($session_id)) { // Needed by write() to detect session_regenerate_id() calls
$this->_session_id = $session_id;
$session_data = $this->_redis->get($this->_key_prefix.$session_id);
is_string($session_data) ? $this->_key_exists = TRUE : $session_data = '';
$this->_fingerprint = md5($session_data); return $session_data; }
return $this->_fail(); }
// ------------------------------------------------------------------------
/** * Write * * Writes (create / update) session data * * @param string $session_id Session ID * @param string $session_data Serialized session data * @return bool */ public function write($session_id, $session_data) { if ( ! isset($this->_redis, $this->_lock_key)) { return $this->_fail(); } // Was the ID regenerated?
elseif ($session_id !== $this->_session_id) { if ( ! $this->_release_lock() OR ! $this->_get_lock($session_id)) { return $this->_fail(); }
$this->_key_exists = FALSE; $this->_session_id = $session_id; }
$this->_redis->setTimeout($this->_lock_key, 300); if ($this->_fingerprint !== ($fingerprint = md5($session_data)) OR $this->_key_exists === FALSE) { if ($this->_redis->set($this->_key_prefix.$session_id, $session_data, $this->_config['expiration'])) { $this->_fingerprint = $fingerprint; $this->_key_exists = TRUE; return $this->_success; }
return $this->_fail(); }
return ($this->_redis->setTimeout($this->_key_prefix.$session_id, $this->_config['expiration'])) ? $this->_success : $this->_fail(); }
// ------------------------------------------------------------------------
/** * Close * * Releases locks and closes connection. * * @return bool */ public function close() { if (isset($this->_redis)) { try { if ($this->_redis->ping() === '+PONG') { $this->_release_lock(); if ($this->_redis->close() === FALSE) { return $this->_fail(); } } } catch (RedisException $e) { log_message('error', 'Session: Got RedisException on close(): '.$e->getMessage()); }
$this->_redis = NULL; return $this->_success; }
return $this->_success; }
// ------------------------------------------------------------------------
/** * Destroy * * Destroys the current session. * * @param string $session_id Session ID * @return bool */ public function destroy($session_id) { if (isset($this->_redis, $this->_lock_key)) { if (($result = $this->_redis->delete($this->_key_prefix.$session_id)) !== 1) { log_message('debug', 'Session: Redis::delete() expected to return 1, got '.var_export($result, TRUE).' instead.'); }
$this->_cookie_destroy(); return $this->_success; }
return $this->_fail(); }
// ------------------------------------------------------------------------
/** * Garbage Collector * * Deletes expired sessions * * @param int $maxlifetime Maximum lifetime of sessions * @return bool */ public function gc($maxlifetime) { // Not necessary, Redis takes care of that.
return $this->_success; }
// ------------------------------------------------------------------------
/** * Get lock * * Acquires an (emulated) lock. * * @param string $session_id Session ID * @return bool */ protected function _get_lock($session_id) { // PHP 7 reuses the SessionHandler object on regeneration,
// so we need to check here if the lock key is for the
// correct session ID.
if ($this->_lock_key === $this->_key_prefix.$session_id.':lock') { return $this->_redis->setTimeout($this->_lock_key, 300); }
// 30 attempts to obtain a lock, in case another request already has it
$lock_key = $this->_key_prefix.$session_id.':lock'; $attempt = 0; do { if (($ttl = $this->_redis->ttl($lock_key)) > 0) { sleep(1); continue; }
if ( ! $this->_redis->setex($lock_key, 300, time())) { log_message('error', 'Session: Error while trying to obtain lock for '.$this->_key_prefix.$session_id); return FALSE; }
$this->_lock_key = $lock_key; break; } while (++$attempt < 30);
if ($attempt === 30) { log_message('error', 'Session: Unable to obtain lock for '.$this->_key_prefix.$session_id.' after 30 attempts, aborting.'); return FALSE; } elseif ($ttl === -1) { log_message('debug', 'Session: Lock for '.$this->_key_prefix.$session_id.' had no TTL, overriding.'); }
$this->_lock = TRUE; return TRUE; }
// ------------------------------------------------------------------------
/** * Release lock * * Releases a previously acquired lock * * @return bool */ protected function _release_lock() { if (isset($this->_redis, $this->_lock_key) && $this->_lock) { if ( ! $this->_redis->delete($this->_lock_key)) { log_message('error', 'Session: Error while trying to free lock for '.$this->_lock_key); return FALSE; }
$this->_lock_key = NULL; $this->_lock = FALSE; }
return TRUE; }
}
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