File: my_session.class.php


<?

//  ----------------------------------------------------------------------

//    |    My Session By Marco Baldini (info [at] marcobaldini [dot] com)      |

//  ----------------------------------------------------------------------

// |    My session is a class that stores session data in a database rather |

// |    than files. This method in most secure that the default session     |

// |    system of PHP                                                       |

//  ----------------------------------------------------------------------        

// |    System Requirements: A web server that support PHP (at least 4.2.0  |

// |    for incoming PostreSQL support) and a DBMS up and running. If you   |

// |    chose MySQL you need at least MySQL 4.0.2.                          |

//  ----------------------------------------------------------------------        

// |  Tested on PHP 4.3.8 and MySql 4.1.3b                                |

//  ----------------------------------------------------------------------    

// |  ATTENTION: The support for PostgreSQL will be implemented in the    |

// |  next minor release (1.2.0).                                         |

//  ----------------------------------------------------------------------    

// | This class has been created and released under the GNU GPL and is    |

// | free to use and redistribute only if this whole header comments and  |

// | copyright statement are not removed. Author gives no warranties. Use |

// | at your own risk. Read the copyright, change log, howto and license. |

//  ----------------------------------------------------------------------



class my_session

{

    

var $session_id;

var $connessione;

var $_MYSESSION_CONF;

var $VARS = array();

var $forced_expire;

var $versione="1.1";

/*    

Invocazione:

require_once('config.DB_eSession.php');

require_once('class.DB_eSession.php');

$sessione = new my_session($_MYSESSION_CONF);

*/



//versione

function get_version() {        



    return $this->versione;    

    

}





//registra variabili

function get_var($nome) {            



    return $this->VARS["$nome"];

        

}



//registra variabili

function registra($nome,$valore) {            

        

        if ($this->_MYSESSION_CONF['CRIPT']==1) {

        

            $cond = "AES_ENCRYPT('".$nome."','".$this->_MYSESSION_CONF['CRIPT_KEY']."')=".$this->_MYSESSION_CONF['NOME'];

            

        } else {



            $cond = $this->_MYSESSION_CONF['NOME']."='$nome'";

            

        }    

        

        $cond .= " AND ".$this->_MYSESSION_CONF['SID']."='".$this->session_id."'";

        

        $this->delete($this->_MYSESSION_CONF['TB_NAME'],$cond,$this->_MYSESSION_CONF['DB_DATABASE']);    

        $this->insert($this->_MYSESSION_CONF['TB_NAME'],$this->_MYSESSION_CONF['DB_DATABASE'],$nome,$valore);

        $this->get_variabili_di_sessione();

}



//deregistra variabili

function cancella($nome) {

        if ($this->_MYSESSION_CONF['CRIPT']==1) {

        

            $cond = "AES_ENCRYPT('".$nome."','".$this->_MYSESSION_CONF['CRIPT_KEY']."')=".$this->_MYSESSION_CONF['NOME'];

            

        } else {



            $cond = $this->_MYSESSION_CONF['NOME']."='$nome'";

            

        }    

        

        $cond .= " AND ".$this->_MYSESSION_CONF['SID']."='".$this->session_id."'";

            

        $this->delete($this->_MYSESSION_CONF['TB_NAME'],$cond,$this->_MYSESSION_CONF['DB_DATABASE']);

        $this->get_variabili_di_sessione();

}





//------COSTRUTTORE------------//

//costruttore PHP 4

function my_session($config) {

    

    $this->__construct($config);

    

}



//costruttore PHP 5

function __construct($config) {



    $this->_MYSESSION_CONF=$config;

        

    $this->db_connection();

    

    $this->sessionid();

    

    //echo "<hr>".$this->session_id."<hr>";

    

    if ($this->controllo_expire_forzato()) $this->destroy();

    

    $_REQUEST[$this->_MYSESSION_CONF['SESSION_VAR_NAME']]=$this->session_id;



}





//---------DISTRUTTORE----------//

//distruttore PHP4

function destroy() {

    

    $this->__destruct();

    

}

//distruttore PHP5

function __destruct() {



    //elimino le variabili di sessione da DB

    $cond=$this->_MYSESSION_CONF['SID']."='".$this->session_id."'";

    $tabelle=$this->_MYSESSION_CONF['TB_NAME'];



    $this->delete($this->_MYSESSION_CONF['TB_NAME'],$cond,$this->_MYSESSION_CONF['DB_DATABASE']);    



}



//------FUNZIONI PRIVATE-------//

function controllo_expire_forzato() {    

    

    if (time()>$this->forced_expire) return 0;

        else return 1;    

}





function get_variabili_di_sessione() {

    

    $this->VARS = array();

    

    $cond=$this->_MYSESSION_CONF['SID']."= '".$this->session_id."'";

    $tabelle=$this->_MYSESSION_CONF['TB_NAME'];

    

    //aggiorno la scadenza della sessione

    $campi_upd=$this->_MYSESSION_CONF['EXP']."=".(time()+($this->_MYSESSION_CONF['DURATA']));



    $this->update($campi_upd,$tabelle,$cond,$this->_MYSESSION_CONF['DB_DATABASE']);

    

    //prelevo le variabili e le metto bell'array VARS        

        if ($this->_MYSESSION_CONF['CRIPT']==1) {

        

            $campi="AES_DECRYPT(".$this->_MYSESSION_CONF['VALORE'].",'".$this->_MYSESSION_CONF['CRIPT_KEY']."') as valore, AES_DECRYPT(".$this->_MYSESSION_CONF['NOME'].",'".$this->_MYSESSION_CONF['CRIPT_KEY']."') as nome";

            

        } else {



            $campi=$this->_MYSESSION_CONF['VALORE']." as valore, ".$this->_MYSESSION_CONF['NOME']." as nome";            

        }        

        

    $r=$this->select($campi,$tabelle,$cond,$this->_MYSESSION_CONF['DB_DATABASE']);

    

    while ($dati=mysql_fetch_array($r)) {

    





        $this->VARS[$dati["nome"]]=$dati["valore"];

        

    }

}







//cerco l'id della sessione, se non lo trovo lo creo nuovo

function sessionid() {



    if ($this->_MYSESSION_CONF['USE_COOKIE']==true) { //cookie abilitati

        

        if (isset($_COOKIE[$this->_MYSESSION_CONF['SESSION_VAR_NAME']])) { // il cookie contiene qualcosa

            

            $this->session_id=$_COOKIE[$this->_MYSESSION_CONF['SESSION_VAR_NAME']];

            

        } else { // cerco l'ID tra i request

            

            if (isset($_REQUEST[$this->_MYSESSION_CONF['SESSION_VAR_NAME']])) {//essite un id in request!

                

                $this->session_id    = $_REQUEST[$this->_MYSESSION_CONF['SESSION_VAR_NAME']];

                $this->get_variabili_di_sessione();

                

            } else { // creo il nuovo ID e lo piazzo nel cookie

                $this->new_sid();

                setcookie ($this->_MYSESSION_CONF['SESSION_VAR_NAME'], $this->session_id,time()+$this->_MYSESSION_CONF['DURATA']);    

            }

            

        }

        

    } else { //cerco altrove



            if (isset($_REQUEST[$this->_MYSESSION_CONF['SESSION_VAR_NAME']])) {//esiste l'id!

                

                $this->session_id    = $_REQUEST[$this->_MYSESSION_CONF['SESSION_VAR_NAME']];

                $this->get_variabili_di_sessione();

                

            } else { // creo il nuovo ID

                

                $this->new_sid();            

                

            }

        

    }    

    

}



//funzione per creare un nuovo id di sessione univoco

function new_sid() {

    

    $this->session_id=$this->genera_stringa();

    

    while ( $this->get_num($this->_MYSESSION_CONF['SID'],$this->_MYSESSION_CONF['TB_NAME'],$this->_MYSESSION_CONF['DB_DATABASE'],$this->session_id) > 0 ) {

    

        $this->session_id=$this->genera_stringa();

        

    }



    $this->forced_expire = time()+ $this->_MYSESSION_CONF['MAX_DURATA'];

    

}



//generero una stringa casuale

function genera_stringa()

{

    

     $alfabeto="qazxswedcvfrtgbnhyujmklpoi0987654321";

     $ris='';

    

    for ($i=0; $i < $this->_MYSESSION_CONF['SID_LEN']; $i++) {

        srand($this->make_seed());        

        $ris .= $alfabeto[rand(0,(strlen($alfabeto)-1))];

    }

    

    return($ris);

}



//funzione casuale per l'inizializzazione del generatore di numeri casuali

function make_seed()

{

   list($usec, $sec) = explode(' ', microtime());

   return (float) $sec + ((float) $usec * 100000);

}



//connessione al database mysql

function db_connection() {



if (!is_resource($this->connessione))

    $this->connessione = mysql_pconnect($this->_MYSESSION_CONF['DB_SERVER'],$this->_MYSESSION_CONF['DB_USERNAME'],$this->_MYSESSION_CONF['DB_PASSWORD']) or die("Connessione non riuscita: " . mysql_error());

    

}



//--------------------FUNZIONI MYSQL



//Numero dei risultati 

function get_num($campo,$tab,$db,$valore) {

    

    $query="select count(*) from $db.$tab where $campo = '$valore'";    

    //echo "<hr>$query<hr>";

    $val=mysql_result(mysql_query($query,$this->connessione),0,0);    

    return $val;

    

}



//select

function select($campi,$tabelle,$cond,$db) {



    $query="SELECT $campi FROM $db.$tabelle WHERE $cond";

    //echo "<hr>$query<hr>";

    $val=mysql_query($query,$this->connessione) or die("Sel:".mysql_error());

    

    return $val;



}



//update

function update($campi,$tabelle,$cond,$db) {

    

    $query="UPDATE $db.$tabelle SET $campi WHERE $cond";

    //echo "<hr>$query<hr>";

    $val=mysql_query($query,$this->connessione) or die("Upd:".mysql_error());

    

    return $val;



}



//delete

function delete($tabelle,$cond,$db) {

    

    $query="DELETE FROM $db.$tabelle WHERE $cond";

    //echo "<hr>$query<hr>";

    $val=mysql_query($query,$this->connessione) or die("Del:".mysql_error());

    

    return $val;



}



//insert

function insert($tabelle,$db,$nome,$val) {

    

    if ($this->_MYSESSION_CONF['CRIPT']==1) {

        $nome= "AES_ENCRYPT('".$nome."','".$this->_MYSESSION_CONF['CRIPT_KEY']."')";

        $val= "AES_ENCRYPT('".$val."','".$this->_MYSESSION_CONF['CRIPT_KEY']."')";

    } else {

        $nome= "'".$nome."'";

        $val= "'".$val."'";

    }

    

    $query="INSERT INTO $db.$tabelle (sid,expires,nome,valore) VALUES ('".$this->session_id."','".(time()+$this->_MYSESSION_CONF['DURATA'])."',$nome,$val)";

    //echo "<hr>$query<hr>";

    $val=mysql_query($query,$this->connessione) or die("Ins:".mysql_error());

    

    return $val;



}



//--------------------    

}

?>
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