/system/libraries/Session.php
PHP | 632 lines | 331 code | 88 blank | 213 comment | 52 complexity | cffdd8b7586b0471719ad92a62ff5e13 MD5 | raw file
- <?php if (!defined('BASEPATH')) exit('No direct script access allowed');
- /**
- * CodeIgniter
- *
- * An open source application development framework for PHP 4.3.2 or newer
- *
- * @package CodeIgniter
- * @author ExpressionEngine Dev Team
- * @copyright Copyright (c) 2006, EllisLab, Inc.
- * @license http://codeigniter.com/user_guide/license.html
- * @link http://codeigniter.com
- * @since Version 1.0
- * @filesource
- */
- // ------------------------------------------------------------------------
- /**
- * Session Class
- *
- * @package CodeIgniter
- * @subpackage Libraries
- * @category Sessions
- * @author ExpressionEngine Dev Team
- * @link http://codeigniter.com/user_guide/libraries/sessions.html
- */
- class CI_Session {
- var $CI;
- var $now;
- var $encryption = TRUE;
- var $use_database = FALSE;
- var $session_table = FALSE;
- var $sess_length = 7200;
- var $sess_cookie = 'ci_session';
- var $userdata = array();
- var $gc_probability = 5;
- var $flashdata_key = 'flash';
- var $time_to_update = 300;
- /**
- * Session Constructor
- *
- * The constructor runs the session routines automatically
- * whenever the class is instantiated.
- */
- function CI_Session()
- {
- $this->CI =& get_instance();
- log_message('debug', "Session Class Initialized");
- $this->sess_run();
- }
-
- // --------------------------------------------------------------------
-
- /**
- * Run the session routines
- *
- * @access public
- * @return void
- */
- function sess_run()
- {
- /*
- * Set the "now" time
- *
- * It can either set to GMT or time(). The pref
- * is set in the config file. If the developer
- * is doing any sort of time localization they
- * might want to set the session time to GMT so
- * they can offset the "last_activity" time
- * based on each user's locale.
- *
- */
- if (is_numeric($this->CI->config->item('sess_time_to_update')))
- {
- $this->time_to_update = $this->CI->config->item('sess_time_to_update');
- }
- if (strtolower($this->CI->config->item('time_reference')) == 'gmt')
- {
- $now = time();
- $this->now = mktime(gmdate("H", $now), gmdate("i", $now), gmdate("s", $now), gmdate("m", $now), gmdate("d", $now), gmdate("Y", $now));
-
- if (strlen($this->now) < 10)
- {
- $this->now = time();
- log_message('error', 'The session class could not set a proper GMT timestamp so the local time() value was used.');
- }
- }
- else
- {
- $this->now = time();
- }
-
- /*
- * Set the session length
- *
- * If the session expiration is set to zero in
- * the config file we'll set the expiration
- * two years from now.
- *
- */
- $expiration = $this->CI->config->item('sess_expiration');
-
- if (is_numeric($expiration))
- {
- if ($expiration > 0)
- {
- $this->sess_length = $this->CI->config->item('sess_expiration');
- }
- else
- {
- $this->sess_length = (60*60*24*365*2);
- }
- }
-
- // Do we need encryption?
- $this->encryption = $this->CI->config->item('sess_encrypt_cookie');
-
- if ($this->encryption == TRUE)
- {
- $this->CI->load->library('encrypt');
- }
- // Are we using a database?
- if ($this->CI->config->item('sess_use_database') === TRUE AND $this->CI->config->item('sess_table_name') != '')
- {
- $this->use_database = TRUE;
- $this->session_table = $this->CI->config->item('sess_table_name');
- $this->CI->load->database();
- }
-
- // Set the cookie name
- if ($this->CI->config->item('sess_cookie_name') != FALSE)
- {
- $this->sess_cookie = $this->CI->config->item('cookie_prefix').$this->CI->config->item('sess_cookie_name');
- }
-
- /*
- * Fetch the current session
- *
- * If a session doesn't exist we'll create
- * a new one. If it does, we'll update it.
- *
- */
- if ( ! $this->sess_read())
- {
- $this->sess_create();
- }
- else
- {
- // We only update the session every five minutes
- if (($this->userdata['last_activity'] + $this->time_to_update) < $this->now)
- {
- $this->sess_update();
- }
- }
-
- // Delete expired sessions if necessary
- if ($this->use_database === TRUE)
- {
- $this->sess_gc();
- }
- // Delete 'old' flashdata (from last request)
- $this->_flashdata_sweep();
-
- // Mark all new flashdata as old (data will be deleted before next request)
- $this->_flashdata_mark();
- }
-
- // --------------------------------------------------------------------
-
- /**
- * Fetch the current session data if it exists
- *
- * @access public
- * @return void
- */
- function sess_read()
- {
- // Fetch the cookie
- $session = $this->CI->input->cookie($this->sess_cookie);
-
- if ($session === FALSE)
- {
- log_message('debug', 'A session cookie was not found.');
- return FALSE;
- }
-
- // Decrypt and unserialize the data
- if ($this->encryption == TRUE)
- {
- $session = $this->CI->encrypt->decode($session);
- }
- $session = @unserialize($this->strip_slashes($session));
-
- if ( ! is_array($session) OR ! isset($session['last_activity']))
- {
- log_message('error', 'The session cookie data did not contain a valid array. This could be a possible hacking attempt.');
- return FALSE;
- }
-
- // Is the session current?
- if (($session['last_activity'] + $this->sess_length) < $this->now)
- {
- $this->sess_destroy();
- return FALSE;
- }
- // Does the IP Match?
- if ($this->CI->config->item('sess_match_ip') == TRUE AND $session['ip_address'] != $this->CI->input->ip_address())
- {
- $this->sess_destroy();
- return FALSE;
- }
-
- // Does the User Agent Match?
- if ($this->CI->config->item('sess_match_useragent') == TRUE AND trim($session['user_agent']) != trim(substr($this->CI->input->user_agent(), 0, 50)))
- {
- $this->sess_destroy();
- return FALSE;
- }
-
- // Is there a corresponding session in the DB?
- if ($this->use_database === TRUE)
- {
- $this->CI->db->where('session_id', $session['session_id']);
-
- if ($this->CI->config->item('sess_match_ip') == TRUE)
- {
- $this->CI->db->where('ip_address', $session['ip_address']);
- }
- if ($this->CI->config->item('sess_match_useragent') == TRUE)
- {
- $this->CI->db->where('user_agent', $session['user_agent']);
- }
-
- $query = $this->CI->db->get($this->session_table);
- if ($query->num_rows() == 0)
- {
- $this->sess_destroy();
- return FALSE;
- }
- else
- {
- $row = $query->row();
- if (($row->last_activity + $this->sess_length) < $this->now)
- {
- $this->CI->db->where('session_id', $session['session_id']);
- $this->CI->db->delete($this->session_table);
- $this->sess_destroy();
- return FALSE;
- }
- }
- }
-
- // Session is valid!
- $this->userdata = $session;
- unset($session);
-
- return TRUE;
- }
-
- // --------------------------------------------------------------------
-
- /**
- * Write the session cookie
- *
- * @access public
- * @return void
- */
- function sess_write()
- {
- $cookie_data = serialize($this->userdata);
-
- if ($this->encryption == TRUE)
- {
- $cookie_data = $this->CI->encrypt->encode($cookie_data);
- }
- setcookie(
- $this->sess_cookie,
- $cookie_data,
- $this->sess_length + time(),
- $this->CI->config->item('cookie_path'),
- $this->CI->config->item('cookie_domain'),
- 0
- );
- }
-
- // --------------------------------------------------------------------
-
- /**
- * Create a new session
- *
- * @access public
- * @return void
- */
- function sess_create()
- {
- $sessid = '';
- while (strlen($sessid) < 32)
- {
- $sessid .= mt_rand(0, mt_getrandmax());
- }
-
- $this->userdata = array(
- 'session_id' => md5(uniqid($sessid, TRUE)),
- 'ip_address' => $this->CI->input->ip_address(),
- 'user_agent' => substr($this->CI->input->user_agent(), 0, 50),
- 'last_activity' => $this->now
- );
-
-
- // Save the session in the DB if needed
- if ($this->use_database === TRUE)
- {
- $this->CI->db->query($this->CI->db->insert_string($this->session_table, $this->userdata));
- }
-
- // Write the cookie
- $this->sess_write();
- }
-
- // --------------------------------------------------------------------
-
- /**
- * Update an existing session
- *
- * @access public
- * @return void
- */
- function sess_update()
- {
- // Save the old session id so we know which record to
- // update in the database if we need it
- $old_sessid = $this->userdata['session_id'];
- $new_sessid = '';
- while (strlen($new_sessid) < 32)
- {
- $new_sessid .= mt_rand(0, mt_getrandmax());
- }
- $new_sessid = md5(uniqid($new_sessid, TRUE));
-
- // Update the session data in the session data array
- $this->userdata['session_id'] = $new_sessid;
- $this->userdata['last_activity'] = $this->now;
-
- // Update the session in the DB if needed
- if ($this->use_database === TRUE)
- {
- $this->CI->db->query($this->CI->db->update_string($this->session_table, array('last_activity' => $this->now, 'session_id' => $new_sessid), array('session_id' => $old_sessid)));
- }
-
- // Write the cookie
- $this->sess_write();
- }
-
- // --------------------------------------------------------------------
-
- /**
- * Destroy the current session
- *
- * @access public
- * @return void
- */
- function sess_destroy()
- {
- setcookie(
- $this->sess_cookie,
- addslashes(serialize(array())),
- ($this->now - 31500000),
- $this->CI->config->item('cookie_path'),
- $this->CI->config->item('cookie_domain'),
- 0
- );
- }
-
- // --------------------------------------------------------------------
-
- /**
- * Garbage collection
- *
- * This deletes expired session rows from database
- * if the probability percentage is met
- *
- * @access public
- * @return void
- */
- function sess_gc()
- {
- srand(time());
- if ((rand() % 100) < $this->gc_probability)
- {
- $expire = $this->now - $this->sess_length;
-
- $this->CI->db->where("last_activity < {$expire}");
- $this->CI->db->delete($this->session_table);
- log_message('debug', 'Session garbage collection performed.');
- }
- }
-
- // --------------------------------------------------------------------
-
- /**
- * Fetch a specific item from the session array
- *
- * @access public
- * @param string
- * @return string
- */
- function userdata($item)
- {
- return ( ! isset($this->userdata[$item])) ? FALSE : $this->userdata[$item];
- }
- // --------------------------------------------------------------------
-
- /**
- * Fetch all session data
- *
- * @access public
- * @return mixed
- */
- function all_userdata()
- {
- return ( ! isset($this->userdata)) ? FALSE : $this->userdata;
- }
-
- // --------------------------------------------------------------------
-
- /**
- * Add or change data in the "userdata" array
- *
- * @access public
- * @param mixed
- * @param string
- * @return void
- */
- function set_userdata($newdata = array(), $newval = '')
- {
- if (is_string($newdata))
- {
- $newdata = array($newdata => $newval);
- }
-
- if (count($newdata) > 0)
- {
- foreach ($newdata as $key => $val)
- {
- $this->userdata[$key] = $val;
- }
- }
- $this->sess_write();
- }
-
- // --------------------------------------------------------------------
-
- /**
- * Delete a session variable from the "userdata" array
- *
- * @access array
- * @return void
- */
- function unset_userdata($newdata = array())
- {
- if (is_string($newdata))
- {
- $newdata = array($newdata => '');
- }
-
- if (count($newdata) > 0)
- {
- foreach ($newdata as $key => $val)
- {
- unset($this->userdata[$key]);
- }
- }
-
- $this->sess_write();
- }
-
- // --------------------------------------------------------------------
-
- /**
- * Strip slashes
- *
- * @access public
- * @param mixed
- * @return mixed
- */
- function strip_slashes($vals)
- {
- if (is_array($vals))
- {
- foreach ($vals as $key=>$val)
- {
- $vals[$key] = $this->strip_slashes($val);
- }
- }
- else
- {
- $vals = stripslashes($vals);
- }
-
- return $vals;
- }
-
- // ------------------------------------------------------------------------
- /**
- * Add or change flashdata, only available
- * until the next request
- *
- * @access public
- * @param mixed
- * @param string
- * @return void
- */
- function set_flashdata($newdata = array(), $newval = '')
- {
- if (is_string($newdata))
- {
- $newdata = array($newdata => $newval);
- }
-
- if (count($newdata) > 0)
- {
- foreach ($newdata as $key => $val)
- {
- $flashdata_key = $this->flashdata_key.':new:'.$key;
- $this->set_userdata($flashdata_key, $val);
- }
- }
- }
-
- // ------------------------------------------------------------------------
- /**
- * Keeps existing flashdata available to next request.
- *
- * @access public
- * @param string
- * @return void
- */
- function keep_flashdata($key)
- {
- // 'old' flashdata gets removed. Here we mark all
- // flashdata as 'new' to preserve it from _flashdata_sweep()
- // Note the function will return FALSE if the $key
- // provided cannot be found
- $old_flashdata_key = $this->flashdata_key.':old:'.$key;
- $value = $this->userdata($old_flashdata_key);
- $new_flashdata_key = $this->flashdata_key.':new:'.$key;
- $this->set_userdata($new_flashdata_key, $value);
- }
-
- // ------------------------------------------------------------------------
- /**
- * Fetch a specific flashdata item from the session array
- *
- * @access public
- * @param string
- * @return string
- */
- function flashdata($key)
- {
- $flashdata_key = $this->flashdata_key.':old:'.$key;
- return $this->userdata($flashdata_key);
- }
- // ------------------------------------------------------------------------
- /**
- * Identifies flashdata as 'old' for removal
- * when _flashdata_sweep() runs.
- *
- * @access private
- * @return void
- */
- function _flashdata_mark()
- {
- $userdata = $this->all_userdata();
- foreach ($userdata as $name => $value)
- {
- $parts = explode(':new:', $name);
- if (is_array($parts) && count($parts) === 2)
- {
- $new_name = $this->flashdata_key.':old:'.$parts[1];
- $this->set_userdata($new_name, $value);
- $this->unset_userdata($name);
- }
- }
- }
- // ------------------------------------------------------------------------
- /**
- * Removes all flashdata marked as 'old'
- *
- * @access private
- * @return void
- */
- function _flashdata_sweep()
- {
- $userdata = $this->all_userdata();
- foreach ($userdata as $key => $value)
- {
- if (strpos($key, ':old:'))
- {
- $this->unset_userdata($key);
- }
- }
- }
-
- }
- // END Session Class
- ?>