<?php
  /*
   *  brisk - auth.phh
   *
   *  Copyright (C) 2006-2012 Matteo Nastasi
   *                          mailto: nastasi@alternativeoutput.it 
   *                                  matteo.nastasi@milug.org
   *                          web: http://www.alternativeoutput.it
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABLILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   * General Public License for more details. You should have received a
   * copy of the GNU General Public License along with this program; if
   * not, write to the Free Software Foundation, Inc, 59 Temple Place -
   * Suite 330, Boston, MA 02111-1307, USA.
   *
   */

require_once("${G_base}Obj/dbase_${G_dbasetype}.phh");

define('CHAL_SHM_DIMS_MIN', 16384);
define('CHAL_SHM_DIMS_MAX', 65536);
define('CHAL_SHM_DIMS_DLT', 16384);
define('CHAL_VALID_TIME',      15);
define('CHAL_GARBAGE_TIMEOUT',  5);


class Challenge {
    var $login;
    var $token;
    var $ip;
    var $tstamp;
    
    function Challenge($login, $token, $ip, $tstamp)
    {
        $this->login  = $login;
        $this->token  = $token;
        $this->ip     = $ip;
        $this->tstamp = $tstamp + CHAL_VALID_TIME;
    }
}

class Challenges {
    static $delta_t;

    var $item;
    var $item_n;
    var $mod;
    var $shm_sz;
    
    var $garbage_timeout;
    
    
    function Challenges()
    {
        $this->item = array();
        $this->item_n = 0;
        $this->garbage_timeout = 0;
        $this->mod = FALSE;
    }
    
    function add($login, $token, $ip, $tstamp) 
    {
        $chal = null;
        
        log_auth("xxx", sprintf("Challenges::add [%s]\n", $login));
        // FIXME Checks here
        if ($login == '') {
            return (FALSE);
        }
        
        // log_auth("xxx", "LOOPI tstamp: ".$this->item[$i]->tstamp."  curtime: ".$curtime);
        
        if (($chal = new Challenge($login, $token, $ip, $tstamp)) == FALSE) {
            return (FALSE);
        }
        
        $this->item[$this->item_n] = $chal;
        $this->item_n++;

        $this->mod = TRUE;

        return ($chal);
    }


    /* remove all istances related to $login */

    function rem($login)
    {
        $ismod  = FALSE;

        for ($i = 0 ; $i < $this->item_n ; $i++) {
            if ($this->item[$i]->login == $login) {
                $ismod = TRUE;
                for ($e = $i ; $e  < ($this->item_n - 1) ; $e++) {
                    $this->item[$e] = $this->item[$e + 1];
                }
        
                $i--;
                $this->item_n--;
                unset($this->item[$this->item_n]);
                $this->mod = TRUE;
            }
        }

        return ($ismod);
    }

    function garbage_manager()
    {
        $curtime = time();

        // FIXME remove set to 0
        $this->garbage_timeout = 0;
        if ($this->garbage_timeout > $curtime)
            return (FALSE);

        $ismod = FALSE;
    
        for ($i = 0 ; $i < $this->item_n ; $i++) {
            log_auth("xxx", "LOOPI item: ".$i." tstamp: ".$this->item[$i]->tstamp."  curtime: ".$curtime);
            if ($this->item[$i]->tstamp < $curtime) {
                for ($e = $i ; $e  < ($this->item_n - 1) ; $e++) {
                    $this->item[$e] = $this->item[$e + 1];
                }
        
                $i--;
                $this->item_n--;
                log_auth("xxx", "LOOPI unset: ".$this->item_n);
                unset($this->item[$this->item_n]);
                $ismod = TRUE;
                $this->mod = TRUE;
            }
        }
    
        log_auth("xxx", "LOOPI AFTER: ".count($this->item)." _n:" .$this->item_n );
    
        $this->garbage_timeout = $curtime + CHAL_GARBAGE_TIMEOUT;
    
        return ($ismod);
    }
  
    function ismod()
    {
        return ($this->mod);
    }

    // Static functions
    static function create()
        {
            $chal =& new Challenges();
    
            $chal->mod = TRUE;

            return $chal;
        }

    function load_data() 
        {
            GLOBAL $sess;
            do {
                if (($tok = @ftok(FTOK_PATH."/challenges", "C")) == -1) {
                    log_main("ftok failed");
                    break;
                }
    
                if (($shm_sz = sharedmem_sz($tok)) == -1) {
                    log_main("shmop_open failed");
                }
	
                if ($shm_sz == -1)
                    $shm_sz = CHAL_SHM_DIMS_MIN;

                if ($shm = shm_attach($tok, $shm_sz)) {
                    $chals = @shm_get_var($shm, $tok); // CHECKED BELOW
	
                    log_only("challenges ==  ".($chals == FALSE ?   "FALSE" : "TRUE")."  challenges ===  ".($chals === FALSE ? "FALSE" : "TRUE")."  challenges isset ".(isset($chals) ?   "TRUE" : "FALSE"));
	
                    if ($chals == FALSE) {
                        log_only("INIT CHALLENGES DATA");
	  
                        $chals =& Challenges::create();
                        if (@shm_put_var($shm, $tok, $chals) == FALSE) {
                            log_only("PUT_VAR FALLITA ".strlen(serialize($chals)));
                            log_only(serialize($chals));
                        }
                        log_shme("Challenges::save_data2");
                    }
                    $chals->shm_sz = $shm_sz;
	
                    shm_detach($shm);
                }

                $chals->garbage_manager();

                return ($chals);
            } while (0);
    
            return (FALSE);
        }
  

    function save_data($chals) 
    {
        $shm =   FALSE;
        $oldmod = $chals->mod;

        if (($tok = @ftok(FTOK_PATH."/challenges", "C")) == -1) 
            return (FALSE);
    
        while ($chals->shm_sz < CHAL_SHM_DIMS_MAX) {
            if (($shm = shm_attach($tok, $chals->shm_sz)) == FALSE)
                break;
      
            if (isset($chals)) 
                log_only("challenges count ".count($chals->item)."  _n: ".$chals->item_n);

            $chals->mod = FALSE;
            if (@shm_put_var($shm, $tok, $chals) != FALSE) {
                log_shme("Challenges::save_data");
                shm_detach($shm);
                return (TRUE);
            }
            $chals->mod = $oldmod;

            if (shm_remove($shm) === FALSE) {
                log_only("REMOVE FALLITA");
                break;
            }
            shm_detach($shm);
            $chals->shm_sz += CHAL_SHM_DIMS_DLT;
        } 

        if ($shm)
            shm_detach($shm);
    
        return (FALSE);
    }

    static function lock_data($is_exclusive)
    {
      if (($res = file_lock(FTOK_PATH."/challenges", $is_exclusive)) != FALSE) {
          self::$delta_t = microtime(TRUE);
          log_lock("LOCK   challenges   [".self::$delta_t."]");
          
          return ($res);
      }

      return (FALSE);
    }
  
    static function unlock_data($res)
    {
        GLOBAL $sess; 
    
        log_lock("UNLOCK challenges   [".(microtime(TRUE) - (self::$delta_t))."]");

        file_unlock($res);
    }
} // End CLASS Challenges

?>