Added Session driver with native PHP sessions and original-flavor CI cookie sessions
diff --git a/system/libraries/Session/drivers/Session_cookie.php b/system/libraries/Session/drivers/Session_cookie.php
new file mode 100755
index 0000000..0982b1e
--- /dev/null
+++ b/system/libraries/Session/drivers/Session_cookie.php
@@ -0,0 +1,583 @@
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP 5.1.6 or newer
+ *
+ * @package CodeIgniter
+ * @author ExpressionEngine Dev Team
+ * @copyright Copyright (c) 2008 - 2010, EllisLab, Inc.
+ * @license http://codeigniter.com/user_guide/license.html
+ * @link http://codeigniter.com
+ * @since Version 2.0
+ * @filesource
+ */
+
+
+/**
+ * Cookie-based session management driver
+ *
+ * This is the CI_Session functionality, as written by EllisLab, abstracted out to a driver.
+ * I have done a little updating for PHP5, and made minor changes to extract this functionality from
+ * the public interface (now in the Session Library), but effectively this code is unchanged.
+ *
+ * @package CodeIgniter
+ * @subpackage Libraries
+ * @category Sessions
+ * @author ExpressionEngine Dev Team and Darren Hill (DChill42)
+ */
+class Session_Cookie extends SessionDriver {
+ private $sess_encrypt_cookie = FALSE;
+ private $sess_use_database = FALSE;
+ private $sess_table_name = '';
+ private $sess_expiration = 7200;
+ private $sess_expire_on_close = FALSE;
+ private $sess_match_ip = FALSE;
+ private $sess_match_useragent = TRUE;
+ private $sess_cookie_name = 'ci_session';
+ private $cookie_prefix = '';
+ private $cookie_path = '';
+ private $cookie_domain = '';
+ private $sess_time_to_update = 300;
+ private $encryption_key = '';
+ private $time_reference = 'time';
+ private $userdata = array();
+ private $CI = null;
+ private $now = 0;
+
+ const gc_probability = 5;
+
+ /**
+ * 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 above or via the config file
+ foreach (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', 'sess_time_to_update', 'time_reference', 'cookie_prefix', 'encryption_key') 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)
+ {
+ $this->CI->load->library('encrypt');
+ }
+
+ // Are we using a database? If so, load it
+ if ($this->sess_use_database === TRUE && $this->sess_table_name != '')
+ {
+ $this->CI->load->database();
+ }
+
+ // 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
+ $this->_sess_gc();
+ }
+
+ /**
+ * Write the session data
+ *
+ * @return void
+ */
+ public function sess_save()
+ {
+ // Are we saving custom data to the DB? If not, all we do is update the cookie
+ if ($this->sess_use_database === FALSE)
+ {
+ $this->_set_cookie();
+ return;
+ }
+
+ // set the custom userdata, the session data we will set in a second
+ $custom_userdata = $this->all_userdata();
+ $cookie_userdata = array();
+
+ // Before continuing, we need to determine if there is any custom data to deal with.
+ // Let's determine this by removing the default indexes to see if there's anything left in the array
+ // and set the session data while we're at it
+ foreach (array('session_id','ip_address','user_agent','last_activity') as $val)
+ {
+ unset($custom_userdata[$val]);
+ $cookie_userdata[$val] = $this->userdata($val);
+ }
+
+ // Did we find any custom data? If not, we turn the empty array into a string
+ // since there's no reason to serialize and store an empty array in the DB
+ if (count($custom_userdata) === 0)
+ {
+ $custom_userdata = '';
+ }
+ else
+ {
+ // Serialize the custom data array so we can store it
+ $custom_userdata = $this->_serialize($custom_userdata);
+ }
+
+ // Run the update query
+ $this->CI->db->where('session_id', $this->userdata('session_id'));
+ $this->CI->db->update($this->sess_table_name,
+ array('last_activity' => $this->userdata('last_activity'), 'user_data' => $custom_userdata));
+
+ // Write the cookie. Notice that we manually pass the cookie data array to the
+ // _set_cookie() function. Normally that function will store $this->userdata, but
+ // in this case that array contains custom data, which we do not want in the cookie.
+ $this->_set_cookie($cookie_userdata);
+ }
+
+ /**
+ * Destroy the current session
+ *
+ * @return void
+ */
+ public function sess_destroy()
+ {
+ // Kill the session DB row
+ if ($this->sess_use_database === TRUE && $this->has_userdata('session_id'))
+ {
+ $this->CI->db->where('session_id', $this->userdata['session_id']);
+ $this->CI->db->delete($this->sess_table_name);
+ }
+
+ // Kill the cookie
+ setcookie($this->sess_cookie_name, addslashes(serialize(array())), ($this->now - 31500000),
+ $this->cookie_path, $this->cookie_domain, 0);
+ }
+
+ /**
+ * Regenerate the current session
+ *
+ * Regenerate the session id
+ *
+ * @param boolean Destroy session data flag (default: false)
+ * @return void
+ */
+ public function sess_regenerate($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 private
+ * @return bool
+ */
+ private function _sess_read()
+ {
+ // Fetch the cookie
+ $session = $this->CI->input->cookie($this->sess_cookie_name);
+
+ // No cookie? Goodbye cruel world!...
+ if ($session === FALSE)
+ {
+ log_message('debug', 'A session cookie was not found.');
+ return FALSE;
+ }
+
+ // Decrypt the cookie data
+ if ($this->sess_encrypt_cookie == TRUE)
+ {
+ $session = $this->CI->encrypt->decode($session);
+ }
+ else
+ {
+ // encryption was not used, so we need to check the md5 hash
+ $hash = substr($session, strlen($session)-32); // get last 32 chars
+ $session = substr($session, 0, strlen($session)-32);
+
+ // Does the md5 hash match? This is to prevent manipulation of session data in userspace
+ if ($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']) || ! isset($session['ip_address']) ||
+ ! isset($session['user_agent']) || ! isset($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, 50)))
+ {
+ $this->sess_destroy();
+ return FALSE;
+ }
+
+ // Is there a corresponding session in the DB?
+ if ($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 = $this->CI->db->get($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 = $query->row();
+ if (isset($row->user_data) && $row->user_data != '')
+ {
+ $custom_data = $this->_unserialize($row->user_data);
+
+ if (is_array($custom_data))
+ {
+ foreach ($custom_data as $key => $val)
+ {
+ $session[$key] = $val;
+ }
+ }
+ }
+ }
+
+ // Session is valid!
+ $this->userdata = $session;
+ unset($session);
+
+ return TRUE;
+ }
+
+ /**
+ * Create a new session
+ *
+ * @access private
+ * @return void
+ */
+ private function _sess_create()
+ {
+ $sessid = '';
+ while (strlen($sessid) < 32)
+ {
+ $sessid .= mt_rand(0, mt_getrandmax());
+ }
+
+ // To make the session ID even more secure we'll combine it with the user's IP
+ $sessid .= $this->CI->input->ip_address();
+
+ $this->set_userdata('session_id', md5(uniqid($sessid, TRUE)));
+ $this->set_userdata('ip_address', $this->CI->input->ip_address());
+ $this->set_userdata('user_agent', substr($this->CI->input->user_agent(), 0, 50));
+ $this->set_userdata('last_activity',$this->now());
+
+
+ // Save the data to the DB if needed
+ if ($this->sess_use_database === TRUE)
+ {
+ $this->CI->db->query($this->CI->db->insert_string($this->sess_table_name, $this->all_userdata()));
+ }
+
+ // Write the cookie
+ $this->_set_cookie();
+ }
+
+ /**
+ * Update an existing session
+ *
+ * @access private
+ * @param boolean Force update flag (default: false)
+ * @return void
+ */
+ private function _sess_update($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;
+ }
+
+ // 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());
+ }
+
+ // 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
+ $new_sessid = md5(uniqid($new_sessid, TRUE));
+
+ // Update the session data in the session data array
+ $this->set_userdata('session_id', $new_sessid);
+ $this->set_userdata('last_activity', $this->now());
+
+ // _set_cookie() will handle this for us if we aren't using database sessions
+ // by pushing all userdata to the cookie.
+ $cookie_data = NULL;
+
+ // Update the session ID and last_activity field in the DB if needed
+ if ($this->sess_use_database === TRUE)
+ {
+ // set cookie explicitly to only have our session data
+ $cookie_data = array();
+ foreach (array('session_id','ip_address','user_agent','last_activity') as $val)
+ {
+ $cookie_data[$val] = $this->userdata[$val];
+ }
+
+ $this->CI->db->query($this->CI->db->update_string($this->sess_table_name,
+ array('last_activity' => $this->now(), 'session_id' => $new_sessid),
+ array('session_id' => $old_sessid)));
+ }
+
+ // Write the cookie
+ $this->_set_cookie($cookie_data);
+ }
+
+ /**
+ * Get the "now" time
+ *
+ * @access private
+ * @return int
+ */
+ private function _get_time()
+ {
+ if (strtolower($this->time_reference) == 'gmt')
+ {
+ $now = time();
+ $time = mktime(gmdate('H', $now), gmdate('i', $now), gmdate('s', $now), gmdate('m', $now),
+ gmdate('d', $now), gmdate('Y', $now));
+ }
+ else
+ {
+ $time = time();
+ }
+
+ return $time;
+ }
+
+ /**
+ * Write the session cookie
+ *
+ * @access private
+ * @param array Cookie name/value pairs
+ * @return void
+ */
+ private function _set_cookie(array $cookie_data = NULL)
+ {
+ if (is_null($cookie_data))
+ {
+ $cookie_data = $this->all_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 : $this->sess_expiration + time();
+
+ // Set the cookie
+ setcookie($this->sess_cookie_name, $cookie_data, $expire, $this->cookie_path, $this->cookie_domain, 0);
+ }
+
+ /**
+ * Serialize an array
+ *
+ * This function first converts any slashes found in the array to a temporary
+ * marker, so when it gets unserialized the slashes will be preserved
+ *
+ * @access private
+ * @param mixed Data to serialize
+ * @return string
+ */
+ private function _serialize($data)
+ {
+ if (is_array($data))
+ {
+ foreach ($data as $key => $val)
+ {
+ if (is_string($val))
+ {
+ $data[$key] = str_replace('\\', '{{slash}}', $val);
+ }
+ }
+ }
+ else
+ {
+ if (is_string($data))
+ {
+ $data = str_replace('\\', '{{slash}}', $data);
+ }
+ }
+
+ return serialize($data);
+ }
+
+ /**
+ * Unserialize
+ *
+ * This function unserializes a data string, then converts any
+ * temporary slash markers back to actual slashes
+ *
+ * @access private
+ * @param string Data to unserialize
+ * @return mixed
+ */
+ private function _unserialize($data)
+ {
+ $data = @unserialize(strip_slashes($data));
+
+ if (is_array($data))
+ {
+ foreach ($data as $key => $val)
+ {
+ if (is_string($val))
+ {
+ $data[$key] = str_replace('{{slash}}', '\\', $val);
+ }
+ }
+
+ return $data;
+ }
+
+ return (is_string($data)) ? str_replace('{{slash}}', '\\', $data) : $data;
+ }
+
+ /**
+ * Garbage collection
+ *
+ * This deletes expired session rows from database
+ * if the probability percentage is met
+ *
+ * @access private
+ * @return void
+ */
+ private function _sess_gc()
+ {
+ if ($this->sess_use_database != TRUE)
+ {
+ return;
+ }
+
+ srand(time());
+ if ((rand() % 100) < self::gc_probability)
+ {
+ $expire = $this->now() - $this->sess_expiration;
+
+ $this->CI->db->where('last_activity < '.$expire);
+ $this->CI->db->delete($this->sess_table_name);
+
+ log_message('debug', 'Session garbage collection performed.');
+ }
+ }
+}
+// END Session_Cookie Class
+
+/* End of file Session_cookie.php */
+/* Location: ./system/libraries/Session/Session.php */
+?>