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authorPhil Sturgeon <email@philsturgeon.co.uk>2012-08-29 15:53:57 +0200
committerPhil Sturgeon <email@philsturgeon.co.uk>2012-08-29 15:53:57 +0200
commit1e40c213610a4bb643e51c2b298629471664163b (patch)
tree79a3e038ab0a8e3ec7a3c878eb05eb9cd9c44fa1 /system/libraries/Session/drivers/Session_cookie.php
parent2d5c209943ef1e2644504e8d5cb32d3d66b45632 (diff)
parent88b636b06dd91807706e2d442d910fe8b6a3b50c (diff)
Merge pull request #353 from dchill42/session
Switched Sessions to use Drivers Adding native PHP sessions and keeping original-flavor CI cookie sessions
Diffstat (limited to 'system/libraries/Session/drivers/Session_cookie.php')
-rwxr-xr-xsystem/libraries/Session/drivers/Session_cookie.php799
1 files changed, 799 insertions, 0 deletions
diff --git a/system/libraries/Session/drivers/Session_cookie.php b/system/libraries/Session/drivers/Session_cookie.php
new file mode 100755
index 000000000..69e5fde14
--- /dev/null
+++ b/system/libraries/Session/drivers/Session_cookie.php
@@ -0,0 +1,799 @@
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP 5.2.4 or newer
+ *
+ * NOTICE OF LICENSE
+ *
+ * Licensed under the Open Software License version 3.0
+ *
+ * This source file is subject to the Open Software License (OSL 3.0) that is
+ * bundled with this package in the files license.txt / license.rst. It is
+ * also available through the world wide web at this URL:
+ * http://opensource.org/licenses/OSL-3.0
+ * If you did not receive a copy of the license and are unable to obtain it
+ * through the world wide web, please send an email to
+ * licensing@ellislab.com so we can send you a copy immediately.
+ *
+ * @package CodeIgniter
+ * @author EllisLab Dev Team
+ * @copyright Copyright (c) 2008 - 2012, EllisLab, Inc. (http://ellislab.com/)
+ * @license http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
+ * @link http://codeigniter.com
+ * @since Version 1.0
+ * @filesource
+ */
+
+/**
+ * Cookie-based session management driver
+ *
+ * This is the classic CI_Session functionality, as written by EllisLab, abstracted out to a driver.
+ *
+ * @package CodeIgniter
+ * @subpackage Libraries
+ * @category Sessions
+ * @author EllisLab Dev Team
+ * @link http://codeigniter.com/user_guide/libraries/sessions.html
+ */
+class CI_Session_cookie extends CI_Session_driver {
+ /**
+ * Whether to encrypt the session cookie
+ *
+ * @var bool
+ */
+ public $sess_encrypt_cookie = FALSE;
+
+ /**
+ * Whether to use to the database for session storage
+ *
+ * @var bool
+ */
+ public $sess_use_database = FALSE;
+
+ /**
+ * Name of the database table in which to store sessions
+ *
+ * @var string
+ */
+ public $sess_table_name = '';
+
+ /**
+ * Length of time (in seconds) for sessions to expire
+ *
+ * @var int
+ */
+ public $sess_expiration = 7200;
+
+ /**
+ * Whether to kill session on close of browser window
+ *
+ * @var bool
+ */
+ public $sess_expire_on_close = FALSE;
+
+ /**
+ * Whether to match session on ip address
+ *
+ * @var bool
+ */
+ public $sess_match_ip = FALSE;
+
+ /**
+ * Whether to match session on user-agent
+ *
+ * @var bool
+ */
+ public $sess_match_useragent = TRUE;
+
+ /**
+ * Name of session cookie
+ *
+ * @var string
+ */
+ public $sess_cookie_name = 'ci_session';
+
+ /**
+ * Session cookie prefix
+ *
+ * @var string
+ */
+ public $cookie_prefix = '';
+
+ /**
+ * Session cookie path
+ *
+ * @var string
+ */
+ public $cookie_path = '';
+
+ /**
+ * Session cookie domain
+ *
+ * @var string
+ */
+ public $cookie_domain = '';
+
+ /**
+ * Whether to set the cookie only on HTTPS connections
+ *
+ * @var bool
+ */
+ public $cookie_secure = FALSE;
+
+ /**
+ * Whether cookie should be allowed only to be sent by the server
+ *
+ * @var bool
+ */
+ public $cookie_httponly = FALSE;
+
+ /**
+ * Interval at which to update session
+ *
+ * @var int
+ */
+ public $sess_time_to_update = 300;
+
+ /**
+ * Key with which to encrypt the session cookie
+ *
+ * @var string
+ */
+ public $encryption_key = '';
+
+ /**
+ * Timezone to use for the current time
+ *
+ * @var string
+ */
+ public $time_reference = 'local';
+
+ /**
+ * Session data
+ *
+ * @var array
+ */
+ public $userdata = array();
+
+ /**
+ * Reference to CodeIgniter instance
+ *
+ * @var object
+ */
+ public $CI;
+
+ /**
+ * Current time
+ *
+ * @var int
+ */
+ public $now;
+
+ /**
+ * Default userdata keys
+ *
+ * @var array
+ */
+ protected $defaults = array(
+ 'session_id' => NULL,
+ 'ip_address' => NULL,
+ 'user_agent' => NULL,
+ 'last_activity' => NULL
+ );
+
+ /**
+ * Data needs DB update flag
+ *
+ * @var bool
+ */
+ protected $data_dirty = FALSE;
+
+ /**
+ * Initialize session driver object
+ *
+ * @access protected
+ * @return void
+ */
+ protected function initialize()
+ {
+ // Set the super object to a local variable for use throughout the class
+ $this->CI =& get_instance();
+
+ // Set all the session preferences, which can either be set
+ // manually via the $params array or via the config file
+ $prefs = array(
+ 'sess_encrypt_cookie',
+ 'sess_use_database',
+ 'sess_table_name',
+ 'sess_expiration',
+ 'sess_expire_on_close',
+ 'sess_match_ip',
+ 'sess_match_useragent',
+ 'sess_cookie_name',
+ 'cookie_path',
+ 'cookie_domain',
+ 'cookie_secure',
+ 'cookie_httponly',
+ 'sess_time_to_update',
+ 'time_reference',
+ 'cookie_prefix',
+ 'encryption_key'
+ );
+ foreach ($prefs as $key)
+ {
+ $this->$key = isset($this->_parent->params[$key]) ? $this->_parent->params[$key] :
+ $this->CI->config->item($key);
+ }
+
+ if ($this->encryption_key === '')
+ {
+ show_error('In order to use the Cookie Session driver you are required to set an encryption key '.
+ 'in your config file.');
+ }
+
+ // Load the string helper so we can use the strip_slashes() function
+ $this->CI->load->helper('string');
+
+ // Do we need encryption? If so, load the encryption class
+ if ($this->sess_encrypt_cookie === TRUE)
+ {
+ $this->CI->load->library('encrypt');
+ }
+
+ // Check for database
+ if ($this->sess_use_database === TRUE && $this->sess_table_name !== '')
+ {
+ // Load database driver
+ $this->CI->load->database();
+
+ // Register shutdown function
+ register_shutdown_function(array($this, '_update_db'));
+ }
+
+ // Set the "now" time. Can either be GMT or server time, based on the config prefs.
+ // We use this to set the "last activity" time
+ $this->now = $this->_get_time();
+
+ // Set the session length. If the session expiration is
+ // set to zero we'll set the expiration two years from now.
+ if ($this->sess_expiration === 0)
+ {
+ $this->sess_expiration = (60*60*24*365*2);
+ }
+
+ // Set the cookie name
+ $this->sess_cookie_name = $this->cookie_prefix.$this->sess_cookie_name;
+
+ // Run the Session routine. If a session doesn't exist we'll
+ // create a new one. If it does, we'll update it.
+ if ( ! $this->_sess_read())
+ {
+ $this->_sess_create();
+ }
+ else
+ {
+ $this->_sess_update();
+ }
+
+ // Delete expired sessions if necessary
+ $this->_sess_gc();
+ }
+
+ /**
+ * Write the session data
+ *
+ * @return void
+ */
+ public function sess_save()
+ {
+ // Check for database
+ if ($this->sess_use_database === TRUE)
+ {
+ // Mark custom data as dirty so we know to update the DB
+ $this->data_dirty = TRUE;
+ }
+
+ // Write the cookie
+ $this->_set_cookie();
+ }
+
+ /**
+ * Destroy the current session
+ *
+ * @return void
+ */
+ public function sess_destroy()
+ {
+ // Kill the session DB row
+ if ($this->sess_use_database === TRUE && isset($this->userdata['session_id']))
+ {
+ $this->CI->db->delete($this->sess_table_name, array('session_id' => $this->userdata['session_id']));
+ }
+
+ // Kill the cookie
+ $this->_setcookie($this->sess_cookie_name, addslashes(serialize(array())), ($this->now - 31500000),
+ $this->cookie_path, $this->cookie_domain, 0);
+
+ // Kill session data
+ $this->userdata = array();
+ }
+
+ /**
+ * Regenerate the current session
+ *
+ * Regenerate the session id
+ *
+ * @param boolean Destroy session data flag (default: false)
+ * @return void
+ */
+ public function sess_regenerate($destroy = false)
+ {
+ // Check destroy flag
+ if ($destroy)
+ {
+ // Destroy old session and create new one
+ $this->sess_destroy();
+ $this->_sess_create();
+ }
+ else
+ {
+ // Just force an update to recreate the id
+ $this->_sess_update(true);
+ }
+ }
+
+ /**
+ * Get a reference to user data array
+ *
+ * @return array - Reference to userdata
+ */
+ public function &get_userdata()
+ {
+ // Return reference to array
+ return $this->userdata;
+ }
+
+ /**
+ * Fetch the current session data if it exists
+ *
+ * @access protected
+ * @return bool
+ */
+ protected function _sess_read()
+ {
+ // Fetch the cookie
+ $session = $this->CI->input->cookie($this->sess_cookie_name);
+
+ // No cookie? Goodbye cruel world!...
+ if ($session === NULL)
+ {
+ log_message('debug', 'A session cookie was not found.');
+ return FALSE;
+ }
+
+ // Check for encryption
+ if ($this->sess_encrypt_cookie === TRUE)
+ {
+ // Decrypt the cookie data
+ $session = $this->CI->encrypt->decode($session);
+ }
+ else
+ {
+ // Encryption was not used, so we need to check the md5 hash in the last 32 chars
+ $len = strlen($session)-32;
+ $hash = substr($session, $len);
+ $session = substr($session, 0, $len);
+
+ // Does the md5 hash match? This is to prevent manipulation of session data in userspace
+ if ($hash !== md5($session.$this->encryption_key))
+ {
+ log_message('error', 'The session cookie data did not match what was expected. '.
+ 'This could be a possible hacking attempt.');
+ $this->sess_destroy();
+ return FALSE;
+ }
+ }
+
+ // Unserialize the session array
+ $session = $this->_unserialize($session);
+
+ // Is the session data we unserialized an array with the correct format?
+ if ( ! is_array($session) || ! isset($session['session_id'], $session['ip_address'], $session['user_agent'],
+ $session['last_activity']))
+ {
+ $this->sess_destroy();
+ return FALSE;
+ }
+
+ // Is the session current?
+ if (($session['last_activity'] + $this->sess_expiration) < $this->now)
+ {
+ $this->sess_destroy();
+ return FALSE;
+ }
+
+ // Does the IP match?
+ if ($this->sess_match_ip === TRUE && $session['ip_address'] !== $this->CI->input->ip_address())
+ {
+ $this->sess_destroy();
+ return FALSE;
+ }
+
+ // Does the User Agent Match?
+ if ($this->sess_match_useragent === TRUE &&
+ trim($session['user_agent']) !== trim(substr($this->CI->input->user_agent(), 0, 120)))
+ {
+ $this->sess_destroy();
+ return FALSE;
+ }
+
+ // Is there a corresponding session in the DB?
+ if ($this->sess_use_database === TRUE)
+ {
+ $this->CI->db->where('session_id', $session['session_id']);
+
+ if ($this->sess_match_ip === TRUE)
+ {
+ $this->CI->db->where('ip_address', $session['ip_address']);
+ }
+
+ if ($this->sess_match_useragent === TRUE)
+ {
+ $this->CI->db->where('user_agent', $session['user_agent']);
+ }
+
+ $query = $this->CI->db->limit(1)->get($this->sess_table_name);
+
+ // No result? Kill it!
+ if ($query->num_rows() === 0)
+ {
+ $this->sess_destroy();
+ return FALSE;
+ }
+
+ // Is there custom data? If so, add it to the main session array
+ $row = $query->row();
+ if ( ! empty($row->user_data))
+ {
+ $custom_data = $this->_unserialize($row->user_data);
+
+ if (is_array($custom_data))
+ {
+ $session = $session + $custom_data;
+ }
+ }
+ }
+
+ // Session is valid!
+ $this->userdata = $session;
+ return TRUE;
+ }
+
+ /**
+ * Create a new session
+ *
+ * @access protected
+ * @return void
+ */
+ protected function _sess_create()
+ {
+ // Initialize userdata
+ $this->userdata = array(
+ 'session_id' => $this->_make_sess_id(),
+ 'ip_address' => $this->CI->input->ip_address(),
+ 'user_agent' => substr($this->CI->input->user_agent(), 0, 120),
+ 'last_activity' => $this->now,
+ );
+
+ // Check for database
+ if ($this->sess_use_database === TRUE)
+ {
+ // Add empty user_data field and save the data to the DB
+ $this->CI->db->set('user_data', '')->insert($this->sess_table_name, $this->userdata);
+ }
+
+ // Write the cookie
+ $this->_set_cookie();
+ }
+
+ /**
+ * Update an existing session
+ *
+ * @access protected
+ * @param boolean Force update flag (default: false)
+ * @return void
+ */
+ protected function _sess_update($force = FALSE)
+ {
+ // We only update the session every five minutes by default (unless forced)
+ if ( ! $force && ($this->userdata['last_activity'] + $this->sess_time_to_update) >= $this->now)
+ {
+ return;
+ }
+
+ // Update last activity to now
+ $this->userdata['last_activity'] = $this->now;
+
+ // Save the old session id so we know which DB record to update
+ $old_sessid = $this->userdata['session_id'];
+
+ // Changing the session ID during an AJAX call causes problems
+ if ( ! $this->CI->input->is_ajax_request())
+ {
+ // Get new id
+ $this->userdata['session_id'] = $this->_make_sess_id();
+ }
+
+ // Check for database
+ if ($this->sess_use_database === TRUE)
+ {
+ // Update the session ID and last_activity field in the DB
+ $this->CI->db->update($this->sess_table_name, array(
+ 'last_activity' => $this->now,
+ 'session_id' => $this->userdata['session_id']
+ ), array('session_id' => $old_sessid));
+ }
+
+ // Write the cookie
+ $this->_set_cookie();
+ }
+
+ /**
+ * Update database with current data
+ *
+ * This gets called from the shutdown function and also
+ * registered with PHP to run at the end of the request
+ * so it's guaranteed to update even when a fatal error
+ * occurs. The first call makes the update and clears the
+ * dirty flag so it won't happen twice.
+ */
+ public function _update_db()
+ {
+ // Check for database and dirty flag and unsaved
+ if ($this->sess_use_database === TRUE && $this->data_dirty === TRUE)
+ {
+ // Set up activity and data fields to be set
+ // If we don't find custom data, user_data will remain an empty string
+ $set = array(
+ 'last_activity' => $this->userdata['last_activity'],
+ 'user_data' => ''
+ );
+
+ // Get the custom userdata, leaving out the defaults
+ // (which get stored in the cookie)
+ $userdata = array_diff_key($this->userdata, $this->defaults);
+
+ // Did we find any custom data?
+ if ( ! empty($userdata))
+ {
+ // Serialize the custom data array so we can store it
+ $set['user_data'] = $this->_serialize($userdata);
+ }
+
+ // Run the update query
+ // Any time we change the session id, it gets updated immediately,
+ // so our where clause below is always safe
+ $this->CI->db->update($this->sess_table_name, $set, array('session_id' => $this->userdata['session_id']));
+
+ // Clear dirty flag to prevent double updates
+ $this->data_dirty = FALSE;
+
+ log_message('debug', 'CI_Session Data Saved To DB');
+ }
+ }
+
+ /**
+ * Generate a new session id
+ *
+ * @return string Hashed session id
+ */
+ protected function _make_sess_id()
+ {
+ $new_sessid = '';
+ do
+ {
+ $new_sessid .= mt_rand(0, mt_getrandmax());
+ }
+ while (strlen($new_sessid) < 32);
+
+ // To make the session ID even more secure we'll combine it with the user's IP
+ $new_sessid .= $this->CI->input->ip_address();
+
+ // Turn it into a hash and return
+ return md5(uniqid($new_sessid, TRUE));
+ }
+
+ /**
+ * Get the "now" time
+ *
+ * @access protected
+ * @return int Time
+ */
+ protected function _get_time()
+ {
+ if ($this->time_reference === 'local' || $this->time_reference === date_default_timezone_get())
+ {
+ return time();
+ }
+
+ $datetime = new DateTime('now', new DateTimeZone($this->time_reference));
+ sscanf($datetime->format('j-n-Y G:i:s'), '%d-%d-%d %d:%d:%d', $day, $month, $year, $hour, $minute, $second);
+
+ return mktime($hour, $minute, $second, $month, $day, $year);
+ }
+
+ /**
+ * Write the session cookie
+ *
+ * @access protected
+ * @return void
+ */
+ protected function _set_cookie()
+ {
+ // Get userdata (only defaults if database)
+ if ($this->sess_use_database === TRUE)
+ {
+ $cookie_data = array_intersect_key($this->userdata, $this->defaults);
+ }
+ else
+ {
+ $cookie_data = $this->userdata;
+ }
+
+ // Serialize the userdata for the cookie
+ $cookie_data = $this->_serialize($cookie_data);
+
+ if ($this->sess_encrypt_cookie === TRUE)
+ {
+ $cookie_data = $this->CI->encrypt->encode($cookie_data);
+ }
+ else
+ {
+ // if encryption is not used, we provide an md5 hash to prevent userside tampering
+ $cookie_data = $cookie_data.md5($cookie_data.$this->encryption_key);
+ }
+
+ $expire = ($this->sess_expire_on_close === TRUE) ? 0 : $this->sess_expiration + time();
+
+ // Set the cookie
+ $this->_setcookie($this->sess_cookie_name, $cookie_data, $expire, $this->cookie_path, $this->cookie_domain,
+ $this->cookie_secure, $this->cookie_httponly);
+ }
+
+ /**
+ * Set a cookie with the system
+ *
+ * This abstraction of the setcookie call allows overriding for unit testing
+ *
+ * @access protected
+ * @param string Cookie name
+ * @param string Cookie value
+ * @param int Expiration time
+ * @param string Cookie path
+ * @param string Cookie domain
+ * @param bool Secure connection flag
+ * @param bool HTTP protocol only flag
+ * @return void
+ */
+ protected function _setcookie($name, $value = '', $expire = 0, $path = '', $domain = '', $secure = false,
+ $httponly = false)
+ {
+ // Set the cookie
+ setcookie($name, $value, $expire, $path, $domain, $secure, $httponly);
+ }
+
+ /**
+ * Serialize an array
+ *
+ * This function first converts any slashes found in the array to a temporary
+ * marker, so when it gets unserialized the slashes will be preserved
+ *
+ * @access protected
+ * @param mixed Data to serialize
+ * @return string Serialized data
+ */
+ protected function _serialize($data)
+ {
+ if (is_array($data))
+ {
+ array_walk_recursive($data, array(&$this, '_escape_slashes'));
+ }
+ elseif (is_string($data))
+ {
+ $data = str_replace('\\', '{{slash}}', $data);
+ }
+ return serialize($data);
+ }
+
+ /**
+ * Escape slashes
+ *
+ * This function converts any slashes found into a temporary marker
+ *
+ * @access protected
+ * @param string Value
+ * @param string Key
+ * @return void
+ */
+ protected function _escape_slashes(&$val, $key)
+ {
+ if (is_string($val))
+ {
+ $val = str_replace('\\', '{{slash}}', $val);
+ }
+ }
+
+ /**
+ * Unserialize
+ *
+ * This function unserializes a data string, then converts any
+ * temporary slash markers back to actual slashes
+ *
+ * @access protected
+ * @param mixed Data to unserialize
+ * @return mixed Unserialized data
+ */
+ protected function _unserialize($data)
+ {
+ $data = @unserialize(strip_slashes(trim($data)));
+
+ if (is_array($data))
+ {
+ array_walk_recursive($data, array(&$this, '_unescape_slashes'));
+ return $data;
+ }
+
+ return is_string($data) ? str_replace('{{slash}}', '\\', $data) : $data;
+ }
+
+ /**
+ * Unescape slashes
+ *
+ * This function converts any slash markers back into actual slashes
+ *
+ * @access protected
+ * @param string Value
+ * @param string Key
+ * @return void
+ */
+ protected function _unescape_slashes(&$val, $key)
+ {
+ if (is_string($val))
+ {
+ $val= str_replace('{{slash}}', '\\', $val);
+ }
+ }
+
+ /**
+ * Garbage collection
+ *
+ * This deletes expired session rows from database
+ * if the probability percentage is met
+ *
+ * @access protected
+ * @return void
+ */
+ protected function _sess_gc()
+ {
+ if ($this->sess_use_database !== TRUE)
+ {
+ return;
+ }
+
+ $probability = ini_get('session.gc_probability');
+ $divisor = ini_get('session.gc_divisor');
+
+ srand(time());
+ if ((mt_rand(0, $divisor) / $divisor) < $probability)
+ {
+ $expire = $this->now - $this->sess_expiration;
+ $this->CI->db->delete($this->sess_table_name, 'last_activity < '.$expire);
+
+ log_message('debug', 'Session garbage collection performed.');
+ }
+ }
+}
+
+/* End of file Session_cookie.php */
+/* Location: ./system/libraries/Session/drivers/Session_cookie.php */