diff options
Diffstat (limited to 'system/libraries')
-rw-r--r-- | system/libraries/Session.php | 467 |
1 files changed, 254 insertions, 213 deletions
diff --git a/system/libraries/Session.php b/system/libraries/Session.php index 31a162e81..9907ade47 100644 --- a/system/libraries/Session.php +++ b/system/libraries/Session.php @@ -26,17 +26,24 @@ */
class CI_Session {
+ var $sess_encrypt_cookie = FALSE;
+ var $sess_use_database = FALSE;
+ var $sess_table_name = '';
+ var $sess_expiration = 7200;
+ var $sess_match_ip = FALSE;
+ var $sess_match_useragent = TRUE;
+ var $sess_cookie_name = 'ci_session';
+ var $cookie_prefix = '';
+ var $cookie_path = '';
+ var $cookie_domain = '';
+ var $sess_time_to_update = 300;
+ var $encryption_key = '';
+ var $flashdata_key = 'flash';
+ var $time_reference = 'time';
+ var $gc_probability = 5;
+ var $userdata = array();
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 $time_to_update = 300;
/**
* Session Constructor
@@ -44,132 +51,70 @@ class CI_Session { * The constructor runs the session routines automatically
* whenever the class is instantiated.
*/
- function CI_Session()
+ function CI_Session($params = array())
{
- $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');
+ // Set the super object to a local variable for use throughout the class
+ $this->CI =& get_instance();
- if (is_numeric($expiration))
+ // 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_match_ip', 'sess_match_useragent', 'sess_cookie_name', 'cookie_path', 'cookie_domain', 'sess_time_to_update', 'time_reference', 'cookie_prefix', 'encryption_key') as $key)
{
- if ($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');
+ $this->$key = (isset($params[$key])) ? $params[$key] : $this->CI->config->item($key);
+ }
- if ($this->encryption == TRUE)
+ // 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)
{
$this->CI->load->library('encrypt');
}
- // Are we using a database?
- if ($this->CI->config->item('sess_use_database') === TRUE AND $this->CI->config->item('sess_table_name') != '')
+ // Are we using a database? If so, load it
+ if ($this->sess_use_database === TRUE AND $this->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)
+
+ // 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_cookie = $this->CI->config->item('cookie_prefix').$this->CI->config->item('sess_cookie_name');
+ $this->sess_expiration = (60*60*24*365*2);
}
+
+ // Set the cookie name
+ $this->sess_cookie_name = $this->cookie_prefix.$this->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.
- *
- */
+ // 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())
{
$this->sess_create();
}
else
{
- // We only update the session every five minutes
- if (($this->userdata['last_activity'] + $this->time_to_update) < $this->now)
- {
- $this->sess_update();
- }
+ $this->sess_update();
}
- // Delete expired sessions if necessary
- if ($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();
+
+ // Delete expired sessions if necessary
+ $this->_sess_gc();
+
+ log_message('debug', "Session routines successfully run");
}
// --------------------------------------------------------------------
@@ -183,28 +128,28 @@ class CI_Session { function sess_read()
{
// Fetch the cookie
- $session = $this->CI->input->cookie($this->sess_cookie);
+ $session = $this->CI->input->cookie($this->sess_cookie_name);
+ // No cookie? Goodbye cruel world!...
if ($session === FALSE)
{
log_message('debug', 'A session cookie was not found.');
return FALSE;
}
- // Decrypt and unserialize the data
- if ($this->encryption == TRUE)
+ // 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
+ $hash = substr($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->CI->config->item('encryption_key')))
+ // 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();
@@ -212,68 +157,75 @@ class CI_Session { }
}
- $session = @unserialize($this->strip_slashes($session));
+ // Unserialize the session array
+ $session = @unserialize(strip_slashes($session));
- if ( ! is_array($session) OR ! isset($session['last_activity']))
+ // Is the session data we unserialized and array with the correct format?
+ if ( ! is_array($session) OR ! isset($session['session_id']) OR ! isset($session['ip_address']) OR ! isset($session['user_agent']) 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.');
+ $this->sess_destroy();
return FALSE;
}
// Is the session current?
- if (($session['last_activity'] + $this->sess_length) < $this->now)
+ if (($session['last_activity'] + $this->sess_expiration) < $this->now)
{
$this->sess_destroy();
return FALSE;
}
// Does the IP Match?
- if ($this->CI->config->item('sess_match_ip') == TRUE AND $session['ip_address'] != $this->CI->input->ip_address())
+ if ($this->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)))
+ if ($this->sess_match_useragent == TRUE AND trim($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)
+ if ($this->sess_use_database === TRUE)
{
$this->CI->db->where('session_id', $session['session_id']);
- if ($this->CI->config->item('sess_match_ip') == TRUE)
+ if ($this->sess_match_ip == TRUE)
{
$this->CI->db->where('ip_address', $session['ip_address']);
}
- if ($this->CI->config->item('sess_match_useragent') == TRUE)
+ if ($this->sess_match_useragent == TRUE)
{
$this->CI->db->where('user_agent', $session['user_agent']);
}
- $query = $this->CI->db->get($this->session_table);
+ $query = $this->CI->db->get($this->sess_table_name);
+ // No result? Kill it!
if ($query->num_rows() == 0)
{
$this->sess_destroy();
return FALSE;
}
- else
+
+ // Is there custom data? If so, add it to the main session array
+ $row = $query->row();
+ if (isset($row->user_data) AND $row->user_data != '')
{
- $row = $query->row();
- if (($row->last_activity + $this->sess_length) < $this->now)
+ $custom_data = @unserialize(strip_slashes($row->user_data));
+
+ if (is_array($custom_data))
{
- $this->CI->db->where('session_id', $session['session_id']);
- $this->CI->db->delete($this->session_table);
- $this->sess_destroy();
- return FALSE;
+ foreach ($custom_data as $key => $val)
+ {
+ $session[$key] = $val;
+ }
}
- }
+ }
}
// Session is valid!
@@ -286,35 +238,61 @@ class CI_Session { // --------------------------------------------------------------------
/**
- * Write the session cookie
+ * Write the session data
*
* @access public
* @return void
*/
function sess_write()
- {
- $cookie_data = serialize($this->userdata);
+ {
+ // 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;
+ }
+
+ // We need two copies of the session data array. One will contain any custom data
+ // that might have been set. The other will contain the data that will be saved to the cookie
+ $cookie_userdata = $this->userdata;
+ $custom_userdata = $this->userdata;
+
+ // 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
+ foreach (array('session_id','ip_address','user_agent','last_activity') as $val)
+ {
+ unset($custom_userdata[$val]);
+ }
- if ($this->encryption == TRUE)
+ // 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)
{
- $cookie_data = $this->CI->encrypt->encode($cookie_data);
+ $custom_userdata = '';
}
else
{
- // if encryption is not used, we provide an md5 hash to prevent userside tampering
- $cookie_data = $cookie_data . md5($cookie_data.$this->CI->config->item('encryption_key'));
+ // Before we serialize the custom data array, let's remove that data from the
+ // main session array since we do not want to save that info to the cookie
+ foreach (array_keys($custom_userdata) as $val)
+ {
+ unset($cookie_userdata[$val]);
+ }
+
+ // Serialize the custom data array so we can store it
+ $custom_userdata = serialize($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));
- setcookie(
- $this->sess_cookie,
- $cookie_data,
- $this->sess_length + time(),
- $this->CI->config->item('cookie_path'),
- $this->CI->config->item('cookie_domain'),
- 0
- );
+ // 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);
}
-
+
// --------------------------------------------------------------------
/**
@@ -330,6 +308,9 @@ class CI_Session { {
$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();
$this->userdata = array(
'session_id' => md5(uniqid($sessid, TRUE)),
@@ -339,14 +320,14 @@ class CI_Session { );
- // Save the session in the DB if needed
- if ($this->use_database === TRUE)
+ // Save the data to the DB if needed
+ if ($this->sess_use_database === TRUE)
{
- $this->CI->db->query($this->CI->db->insert_string($this->session_table, $this->userdata));
+ $this->CI->db->query($this->CI->db->insert_string($this->sess_table_name, $this->userdata));
}
// Write the cookie
- $this->sess_write();
+ $this->_set_cookie();
}
// --------------------------------------------------------------------
@@ -358,7 +339,13 @@ class CI_Session { * @return void
*/
function sess_update()
- {
+ {
+ // We only update the session every five minutes by default
+ if (($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'];
@@ -367,20 +354,25 @@ class CI_Session { {
$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->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' => $old_sessid)));
+ // Update the session ID and last_activity field in the DB if needed
+ if ($this->sess_use_database === TRUE)
+ {
+ $this->CI->db->query($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->sess_write();
+ $this->_set_cookie();
}
// --------------------------------------------------------------------
@@ -392,13 +384,21 @@ class CI_Session { * @return void
*/
function sess_destroy()
- {
+ {
+ // Kill the session DB row
+ if ($this->sess_use_database === TRUE AND isset($this->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,
+ $this->sess_cookie_name,
addslashes(serialize(array())),
($this->now - 31500000),
- $this->CI->config->item('cookie_path'),
- $this->CI->config->item('cookie_domain'),
+ $this->cookie_path,
+ $this->cookie_domain,
0
);
}
@@ -406,31 +406,6 @@ class CI_Session { // --------------------------------------------------------------------
/**
- * 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
@@ -509,33 +484,6 @@ class CI_Session { $this->sess_write();
}
- // --------------------------------------------------------------------
-
- /**
- * Strip slashes
- *
- * @access public
- * @param mixed
- * @return mixed
- */
- function strip_slashes($vals)
- {
- if (is_array($vals))
- {
- foreach ($vals as $key=>$val)
- {
- $vals[$key] = $this->strip_slashes($val);
- }
- }
- else
- {
- $vals = stripslashes($vals);
- }
-
- return $vals;
- }
-
-
// ------------------------------------------------------------------------
/**
@@ -646,6 +594,99 @@ class CI_Session { }
}
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Get the "now" time
+ *
+ * @access private
+ * @return string
+ */
+ function _get_time()
+ {
+ if (strtolower($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 $time;
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Write the session cookie
+ *
+ * @access public
+ * @return void
+ */
+ function _set_cookie($cookie_data = NULL)
+ {
+ if (is_null($cookie_data))
+ {
+ $cookie_data = $this->userdata;
+ }
+
+ // Serialize the userdata for the cookie
+ $cookie_data = serialize($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);
+ }
+
+ // Set the cookie
+ setcookie(
+ $this->sess_cookie_name,
+ $cookie_data,
+ $this->sess_expiration + time(),
+ $this->cookie_path,
+ $this->cookie_domain,
+ 0
+ );
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Garbage collection
+ *
+ * This deletes expired session rows from database
+ * if the probability percentage is met
+ *
+ * @access public
+ * @return void
+ */
+ function _sess_gc()
+ {
+ if ($this->sess_use_database != TRUE)
+ {
+ return;
+ }
+
+ srand(time());
+ if ((rand() % 100) < $this->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 Class
|