<?php
/**
 * ---------------------------------------------------------------------
 * GLPI - Gestionnaire Libre de Parc Informatique
 * Copyright (C) 2015-2021 Teclib' and contributors.
 *
 * http://glpi-project.org
 *
 * based on GLPI - Gestionnaire Libre de Parc Informatique
 * Copyright (C) 2003-2014 by the INDEPNET Development Team.
 *
 * ---------------------------------------------------------------------
 *
 * LICENSE
 *
 * This file is part of GLPI.
 *
 * GLPI 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.
 *
 * GLPI is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY 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 GLPI. If not, see <http://www.gnu.org/licenses/>.
 * ---------------------------------------------------------------------
*/

/**
 * Represent an IPv4 or an IPv6 address. Both textual (ie. human readable)
 * and binary (ie. : used for request) are present
 * @since 0.84
 */

if (!defined('GLPI_ROOT')) {
   die("Sorry. You can't access this file directly");
}

/** Class IPAddress : Represents an IPv4 or an IPv6 address. Both textual (ie. human readable)
* and binary (ie. : used for SQL requests) are present inside the DB.
* The class itself contains three protected attributes. If the address is valid, then, these
* attributes are not empty.
* This object is usefull for SQL research and binary<=>textual conversions.
* @warning textual (ie. human readable) representation is not unique for IPv6 addresses :
* 2001:db8:0:85a3\::ac1f:8001 = 2001:db8:0:85a3:0:0:ac1f:8001
* @warning All textual representation of IPv6 addresses conforms to RFC 5952 : they are
* automatically converted by IPAddress::setAddressFromString().
* @since 0.84
**/
class IPAddress extends CommonDBChild {

   // From CommonDBChild
   static public $itemtype       = 'itemtype';
   static public $items_id       = 'items_id';
   public $dohistory             = false;

   public $history_blacklist     = ['binary_0', 'binary_1', 'binary_2', 'binary_3'];

   /// $version (integer) : version of the adresse. Should be 4 or 6, or empty if not valid address
   protected $version = '';
   /// $this->textual (string) : human readable of the IP adress (for instance : 192.168.0.0,
   /// 2001:db8:0:85a3\::ac1f:8001)
   protected $textual = '';
   /// $this->binary (bytes[4]) : binary version for the SQL requests. For IPv4 addresses, the
   /// first three bytes are set to [0, 0, 0xffff]
   protected $binary  = [0, 0, 0, 0];
   //to know is IPV4 is Dotted quoad Format
   protected $isDottedQuoadFormat = false;

   static $rightname  = 'internet';

   //////////////////////////////////////////////////////////////////////////////
   // CommonDBTM related methods
   //////////////////////////////////////////////////////////////////////////////


   /**
    * @param IPAddress|string|integer[] $ipaddress (default '')
   **/
   function __construct($ipaddress = '') {

      // First, be sure that the parent is correctly initialised
      parent::__construct();

      // If $ipaddress if empty, then, empty address !
      if ($ipaddress != '') {

         // If $ipaddress if an IPAddress, then just clone it
         if ($ipaddress instanceof IPAddress) {
            $this->version = $ipaddress->version;
            $this->textual = $ipaddress->textual;
            $this->binary  = $ipaddress->binary;
            $this->fields  = $ipaddress->fields;

         } else {
            // Else, check a binary then a string
            if (!$this->setAddressFromBinary($ipaddress)) {
               $this->setAddressFromString($ipaddress);
            }
         }
      }
   }


   static function getTypeName($nb = 0) {
      return _n('IP address', 'IP addresses', $nb);
   }


   /**
    * @param $input
   **/
   function prepareInput($input) {

      // If $input['name'] does not exists, then, don't check anything !
      if (isset($input['name'])) {
         // WARNING: we must in every case, because, sometimes, fields are partially feels

         // If previous value differs from current one, then check it !
         $this->setAddressFromString($input['name']);
         if (!$this->is_valid()) {
            if (isset($input['is_dynamic']) && $input['is_dynamic']) {
               // We allow invalid IPs that are dynamics !
               $input['version']  = 0;
               $input['binary_0'] = 0;
               $input['binary_1'] = 0;
               $input['binary_2'] = 0;
               $input['binary_3'] = 0;
               return $input;
            }
            //TRANS: %s is the invalid address
            $msg = sprintf(__('%1$s: %2$s'), __('Invalid IP address'), $input['name']);
            Session::addMessageAfterRedirect($msg, false, ERROR);
            return false;
         }
      }
      if (isset($input['itemtype']) && isset($input['items_id'])) {
         $input['mainitemtype'] = 'NULL';
         $input['mainitems_id'] = 0;
         if ($input['itemtype'] == 'NetworkName') {
            $name = new NetworkName();
            if ($name->getFromDB($input['items_id'])) {
               if ($port = getItemForItemtype($name->getField('itemtype'))) {
                  if ($port->getFromDB($name->getField('items_id'))) {
                     if (isset($port->fields['itemtype']) && isset($port->fields['items_id'])) {
                        $input['mainitemtype'] = $port->fields['itemtype'];
                        $input['mainitems_id'] = $port->fields['items_id'];
                     }
                  }
               }
            }
         }
      }

      return array_merge($input, $this->setArrayFromAddress($input, "version", "name", "binary"));
   }


   function prepareInputForAdd($input) {

      return parent::prepareInputForAdd($this->prepareInput($input));
   }


   function prepareInputForUpdate($input) {
      return parent::prepareInputForUpdate($this->prepareInput($input));
   }


   function post_addItem() {
      IPAddress_IPNetwork::addIPAddress($this);
      parent::post_addItem();
   }


   function post_updateItem($history = 1) {

      if ((isset($this->oldvalues['name']))
          || (isset($this->oldvalues['entities_id']))) {

         $link = new IPAddress_IPNetwork();
         $link->cleanDBonItemDelete($this->getType(), $this->getID());
         $link->addIPAddress($this);
      }

      parent::post_updateItem($history);
   }


   function cleanDBonPurge() {

      $this->deleteChildrenAndRelationsFromDb(
         [
            IPAddress_IPNetwork::class,
         ]
      );
   }


   function post_getFromDB () {

      // Don't forget set local object from DB field
      $this->setAddressFromArray($this->fields, "version", "name", "binary");
   }


   static function showForItem(CommonGLPI $item, $withtemplate = 0) {
      global $CFG_GLPI;

      if ($item->getType() == 'IPNetwork') {

         if (isset($_GET["start"])) {
            $start = $_GET["start"];
         } else {
            $start = 0;
         }

         if (!empty($_GET["order"])) {
            $table_options['order'] = $_GET["order"];
         } else {
            $table_options['order'] = 'ip';
         }

         $order_by_itemtype             = ($table_options['order'] == 'itemtype');

         $table_options['SQL_options']  = [
            'LIMIT'  => $_SESSION['glpilist_limit'],
            'START'  => $start
         ];

         $table           = new HTMLTableMain();
         $content         = "<a href='javascript:reloadTab(\"order=ip\");'>" .
                              self::getTypeName(Session::getPluralNumber()) . "</a>";
         $internet_column = $table->addHeader('IP Address', $content);
         $content         = sprintf(__('%1$s - %2$s'), _n('Item', 'Items', Session::getPluralNumber()),
                                    "<a href='javascript:reloadTab(\"order=itemtype\");'>" .
                                      __('Order by item type') . "</a>");
         $item_column     = $table->addHeader('Item', $content);

         if ($order_by_itemtype) {
            foreach ($CFG_GLPI["networkport_types"] as $itemtype) {
               $table_options['group_'.$itemtype] = $table->createGroup($itemtype,
                                                                        $itemtype::getTypeName(Session::getPluralNumber()));

               self::getHTMLTableHeader($item->getType(), $table_options['group_'.$itemtype],
                                        $item_column, null, $table_options);

            }
         }

         $table_options['group_None'] = $table->createGroup('Main', __('Other kind of items'));

         self::getHTMLTableHeader($item->getType(), $table_options['group_None'], $item_column,
                                  null, $table_options);

         self::getHTMLTableCellsForItem(null, $item, null, $table_options);

         if ($table->getNumberOfRows() > 0) {
            $count = self::countForItem($item);
            Html::printAjaxPager(self::getTypeName(Session::getPluralNumber()), $start, $count);

            Session::initNavigateListItems(__CLASS__,
                                           //TRANS : %1$s is the itemtype name,
                                           //        %2$s is the name of the item (used for headings of a list)
                                           sprintf(__('%1$s = %2$s'),
                                                   $item->getTypeName(1), $item->getName()));
            $table->display(['display_title_for_each_group' => $order_by_itemtype,
                                  'display_super_for_each_group' => false,
                                  'display_tfoot'                => false]);

            Html::printAjaxPager(self::getTypeName(Session::getPluralNumber()), $start, $count);
         } else {
            echo "<table class='tab_cadre_fixe'>";
            echo "<tr><th>".__('No IP address found')."</th></tr>";
            echo "</table>";
         }
      }
   }


   static function displayTabContentForItem(CommonGLPI $item, $tabnum = 1, $withtemplate = 0) {

      switch ($item->getType()) {
         case 'IPNetwork' :
            self::showForItem($item, $withtemplate);
            break;
      }
   }


   /**
    * @param $item      CommonDBTM object
   **/
   static function countForItem(CommonDBTM $item) {
      global $DB;

      switch ($item->getType()) {
         case 'IPNetwork' :
            $result = $DB->request([
               'COUNT'  => 'cpt',
               'FROM'   => 'glpi_ipaddresses_ipnetworks',
               'WHERE'  => [
                  'ipnetworks_id'   => $item->getID()
               ]
            ])->next();
            return $result['cpt'];
      }
   }


   /**
    * @param $item           CommonGLPI object
    * @param $withtemplate   (default 0)
    *
    * @return string
   **/
   function getTabNameForItem(CommonGLPI $item, $withtemplate = 0) {

      if ($item->getID()
          && $item->can($item->getField('id'), READ)) {
         $nb = 0;
         if ($_SESSION['glpishow_count_on_tabs']) {
            $nb = self::countForItem($item);
         }
         return self::createTabEntry(self::getTypeName(Session::getPluralNumber()), $nb);
      }
      return '';
   }


   //////////////////////////////////////////////////////////////////////////////
   // IP address specific methods (check, transformation ...)
   //////////////////////////////////////////////////////////////////////////////


   /**
    * Disable the address
   **/
   function disableAddress() {

      $this->version = '';
      $this->textual = '';
      $this->binary  = '';
   }


   /**
    * \brief Fill an array from the the local address object
    * Fill an array from the the local address object. Usefull for feeding $input variable for
    * preparing input to alter database.
    * If the field name is empty, then, the field is not set
    * If the object is not valid, then, version = 0, textual = "" and binary = (0, 0, 0, 0)
    *
    * @param array  $array         the array to Fill
    * @param string $versionField  the name of the key inside $array that contains de IP version number
    * @param string $textualField  the name of the key inside $array that contains de textual version
    * @param string $binaryField   the name of the key inside $array that contains de binary.
    *                              Each element of the array is post-fixed by _i, with i the index
    *
    * @return array the array altered
   **/
   function setArrayFromAddress(array $array, $versionField, $textualField, $binaryField) {

      if (!empty($versionField)) {
         $version = $this->getVersion();
         if ($version !== false) {
            $array[$versionField] = $version;
         } else {
            $array[$versionField] = "0";
         }
      }

      if (!empty($textualField)) {
         $textual = $this->getTextual();
         if ($textual !== false) {
            $array[$textualField] = $textual;
         } else {
            $array[$textualField] = "";
         }
      }

      if (!empty($binaryField)) {
         $binary = $this->getBinary();
         for ($i = 0; $i < 4; ++$i) {
            if ($binary !== false) {
               $array[$binaryField."_".$i] = $binary[$i];
            } else {
               $array[$binaryField."_".$i] = '0';
            }
         }
      }
      return $array;
   }


   /**
    * \brief Fill the local address object from an array
    * Fill the local address object from an array. Usefull for reading $input
    *
    * @param array  $array         the array to Fill
    * @param string $versionField  the name of the key inside $array that contains de IP version number
    * @param string $textualField  the name of the key inside $array that contains de textual version
    * @param string $binaryField   the name of the key inside $array that contains de binary.
    *                              Each element of the array is post-fixed by _i, with i the index
    *
    * If the field name is empty, then, the field is not set
    *
    * @return true is succeffully defined
   **/
   function setAddressFromArray(array $array, $versionField, $textualField, $binaryField) {

      // First, we empty the fields to notify that this address is not valid
      $this->disableAddress();

      if (!isset($array[$versionField])) {
         return false;
      }
      if (!isset($array[$textualField])) {
         return false;
      }
      if (!isset($array[$binaryField."_0"])
          || !isset($array[$binaryField."_1"])
          || !isset($array[$binaryField."_2"])
          || !isset($array[$binaryField."_3"])) {
         return false;
      }

      $this->version    = $array[$versionField];
      $this->textual    = $array[$textualField];
      $this->binary     = [];
      $this->binary[0]  = ($array[$binaryField."_0"] + 0);
      $this->binary[1]  = ($array[$binaryField."_1"] + 0);
      $this->binary[2]  = ($array[$binaryField."_2"] + 0);
      $this->binary[3]  = ($array[$binaryField."_3"] + 0);
      return true;
   }


   /**
    * Check address validity
   **/
   function is_valid() {
      return (($this->version != '') && ($this->textual != '') && ($this->binary != ''));
   }


   function getVersion() {

      if ($this->version != '') {
         return $this->version;
      }
      return false;
   }


   function is_ipv4() {
      return ($this->getVersion() == 4);
   }


   function is_ipv6() {
      return ($this->getVersion() == 6);
   }


   function getTextual() {

      if ($this->textual != '') {
         return $this->textual;
      }
      return false;
   }


   function getBinary() {

      if ($this->binary != '') {
         return $this->binary;
      }
      return false;
   }


   /**
    * Transform an IPv4 address to IPv6
    *
    * @param integer|integer[] $address (bytes[4] or bytes) the address to transform.
    *
    * @return integer[]|false IPv6 mapped address
   **/
   static function getIPv4ToIPv6Address($address) {

      if (is_numeric($address)) {
         return [0, 0, 0xffff, $address];
      }
      if ((is_array($address)) && (count($address) == 4)) {
         return self::getIPv4ToIPv6Address($address[3]);
      }
      return false;
   }


   /**
    * Check an address to see if it is IPv4 mapped to IPv6 address
    *
    * @param integer[] $address (bytes[4]) the address to check
    *
    * @return true if the address is IPv4 mapped to IPv6
   **/
   static function isIPv4MappedToIPv6Address($address) {

      if (is_array($address) && (count($address) == 4)) {
         if (($address[0] == 0) && ($address[1] == 0) && ($address[2] == 0xffff)) {
            return true;
         }
         return false;
      }
      return false;
   }


   /**
    * Replace textual representation by its canonical form.
    *
    * @return void
   **/
   function canonicalizeTextual() {
      $this->setAddressFromBinary($this->getBinary());
   }


   /**
    * \brief define an address from a string
    * Convert a textual address (string) to binary one. Opposite function that
    * setAddressFromBinary(). If item is valid ($itemtype not empty and $items_id > 0) then first
    * try to find it inside the database and load it from database.
    * \warning The resulting binary form is created inside the current object
    *
    * @param string  $address   textual (ie. human readable) address
    * @param string  $itemtype  type of the item this address has to be attached (default '')
    * @param integer $items_id  id of the item this address has to be attached (default -1)
    *
    * @return true if the address is valid.
   **/
   function setAddressFromString($address, $itemtype = "", $items_id = -1) {
      global $DB;

      $this->disableAddress();

      if (!is_string($address)) {
         return false;
      }

      $address = trim($address);

      if (empty($address)) {
         return false;
      }

      if (!empty($itemtype)
          && ($items_id > 0)) {
         $iterator = $DB->request([
            'SELECT' => 'id',
            'FROM'   => $this->getTable(),
            'WHERE'  => [
               'items_id'  => $items_id,
               'itemtype'  => $itemtype,
               'name'      => $address
            ]
         ]);

         if (count($iterator) == 1) {
            $line = $iterator->next();
            if ($this->getFromDB($line["id"])) {
               return true;
            }
         }
      }

      //if it IPV4 dotted-quoad format ::ffff:192.168.1.1
      //remove ::ffff: to manage only IPV4 part
      //keep in memory that have a special format
      $this->isDottedQuoadFormat = false;
      if (preg_match("/^::ffff:(?:[0-9]{1,3}\.){3}[0-9]{1,3}$/", $address, $regs)) {
         $address = substr($address, 7);
         $this->isDottedQuoadFormat = true;
      }

      unset($binary);
      $singletons = explode(".", $address);
      // First, check to see if it is an IPv4 address
      if (count($singletons) == 4) {
         $binary = 0;
         foreach ($singletons as $singleton) {
            if (!is_numeric($singleton)) {
               return false;
            }
            $singleton = intval($singleton);
            if (($singleton < 0) || ($singleton > 255)) {
               return false;
            }
            $binary *= 256;
            $binary += intval($singleton);
         }
         $binary  = self::getIPv4ToIPv6Address($binary);
      }

      // Else, it should be an IPv6 address
      $singletons = explode(":", $address);
      // Minimum IPv6 address is "::". So, we check that there is at least 3 singletons in the array
      // And no more than 8 singletons
      if ((count($singletons) >= 3) && (count($singletons) <= 8)) {
         $empty_count = 0;
         foreach ($singletons as $singleton) {
            $singleton = trim($singleton);
            // First, we check that each singleton is 4 hexadecimal !
            if (!preg_match("/^[0-9A-Fa-f]{0,4}$/", $singleton, $regs)) {
               return false;
            }
            if ($singleton === '') {
               $empty_count ++;
            }
         }

         // EXTREMITY CHECKS :
         // If it starts with colon : the second one must be empty too (ie.: :2001 is not valid)
         $start_with_empty = ($singletons[0] === '');
         if (($start_with_empty) && ($singletons[1] !== '')) {
            return false;
         }

         // If it ends with colon : the previous one must be empty too (ie.: 2001: is not valid)
         $end_with_empty = ($singletons[count($singletons) - 1] === '');
         if (($end_with_empty) && ($singletons[count($singletons) - 2] !== '')) {
            return false;
         }
         // END OF EXTREMITY CHECKS

         // The number of empty singletons depends on the type of contraction
         switch ($empty_count) {

            case 0: // No empty singleton => no contraction at all
               // Thus, its side must be 8 !
               if (count($singletons) != 8) {
                  return false;
               }
               break;

            case 1:
               // One empty singleton : must be in the middle, otherwise EXTREMITY CHECKS
               // would return false
               break;

            case 2: // If there is two empty singletons then it must be at the beginning or the end
               if (!($start_with_empty XOR $end_with_empty)) {
                  return false;
               }
               // Thus remove one of both empty singletons.
               if ($start_with_empty) {
                  unset($singletons[0]);
               } else { // $end_with_empty == true
                  unset($singletons[count($singletons) - 1]);
               }
               break;

            case 3: // Only '::' allows three empty singletons ('::x::' = four empty singletons)
               if (!($start_with_empty AND $end_with_empty)) {
                  return false;
               }
               // Middle value must be '' otherwise EXTREMITY CHECKS returned an error
               if (count($singletons) != 3) {
                  return false;
               }
               $singletons = [''];
               break;

            default:
               return false;

         }

         // Here, we are sure that $singletons are valids and only contains 1 empty singleton that
         // will be convert to as many '0' as necessary to reach 8 singletons

         $numberEmpty = 9 - count($singletons); // = 8 - (count($singletons) - 1)

         $epanded = [];
         foreach ($singletons as $singleton) {
            if ($singleton === '') {
               $epanded = array_merge($epanded, array_fill(0, $numberEmpty, 0));
            } else {
               $epanded[] = hexdec($singleton);
            }
         }

         $binary = [];
         for ($i = 0; $i < 4; $i++) {
            $binary[$i] = $epanded[2 * $i + 0] * 65536 + $epanded[2 * $i + 1];
         }

      }

      // $binary is an array that is only defined for IPv4 or IPv6 address
      if (isset($binary)) {
         // Calling setAddressFromBinary is usefull to recheck one more time inside
         // glpi_ipaddresses table and to make canonical textual version
         return $this->setAddressFromBinary($binary, $itemtype, $items_id);
      }

      // Else, it is not IPv4 nor IPv6 address
      return false;
   }


   /**
    * \brief define an address from a binary
    * Convert a binary address (bytes[4]) to textual one. Opposite function that
    * setAddressFromString(). If item is valid ($itemtype not empty and $items_id > 0) then first
    * try to find it inside the database and load it from database. textual version is condensed
    * one (ie : 2001:db8:0:85a3\::ac1f:8001 rather than 2001:0db8:0000:85a3:0000:0000:ac1f:8001)
    * \warning The resulting binary form is created inside the current object
    *
    * @param integer[] $address   (bytes[4]) binary (ie. SQL requests) address
    * @param string    $itemtype  type of the item this address has to be attached (default '')
    * @param integer   $items_id  id of the item this address has to be attached (default -1)
    *
    * @return true if the address is valid.
   **/
   function setAddressFromBinary($address, $itemtype = "", $items_id = -1) {
      global $DB;

      $this->disableAddress();
      if ((!is_array($address)) || (count($address) != 4)) {
         return false;
      }
      if (!empty($itemtype)
          && ($items_id > 0)) {
         $where = [
            'itemtype'  => $itemtype,
            'items_id'  => $items_id
         ];

         for ($i = 0; $i < 4; ++$i) {
            $where["binary_$i"] = $address[$i];
         }

         $iterator = $DB->request([
            'SELECT' => 'id',
            'FROM'   => $this->getTable(),
            'WHERE'  => $where
         ]);

         if (count($iterator) == 1) {
            $line = $iterator->next();
            if ($this->getFromDB($line["id"])) {
               return true;
            }
         }
      }
      $binary      = [];
      $textual     = [];
      $currentNull = "";
      foreach ($address as $singleton) {
         if (!is_numeric($singleton)) {
            return false;
         }
         $singleton = (int)$singleton;
         $binary[]  = $singleton;
         $singleton = str_pad(dechex($singleton), 8, "0", STR_PAD_LEFT);
         $elt       = ltrim(substr($singleton, 0, 4), "0");
         if (empty($elt)) {
            $textual[]    = "0";
            $currentNull .= "1";
         } else {
            $currentNull .= "0";
            $textual[]    = $elt;
         }
         $elt = ltrim(substr($singleton, 4, 4), "0");
         if (empty($elt)) {
            $textual[]    = "0";
            $currentNull .= "1";
         } else {
            $currentNull .= "0";
            $textual[]    = $elt;
         }
      }

      if (isset($binary) && (count($binary) == 4)) {
         if (self::isIPv4MappedToIPv6Address($binary)) {
            $this->version = 4;
         } else {
            $this->version = 6;
         }
      } else {
         return false;
      }

      $this->binary = $binary;
      if ($this->getVersion() == 4) {
         $hexValue = str_pad($textual[6], 4, "0", STR_PAD_LEFT).str_pad($textual[7], 4, "0",
                                                                        STR_PAD_LEFT);
         $textual  = [];
         for ($i = 0; $i < 4; $i++) {
            $textual[] = hexdec($hexValue[2*$i+0].$hexValue[2*$i+1]);
         }
         $textual = implode('.', $textual);
      } else {
         foreach (["11111111", "1111111", "111111", "11111", "1111", "111", "11"] as $elt) {
            $pos = strpos($currentNull, $elt);
            if ($pos !== false) {
               $first = array_slice($textual, 0, $pos);
               if (count($first) == 0) {
                  $first = [""];
               }
               $second = array_slice($textual, $pos + strlen($elt));
               if (count($second) == 0) {
                  $second = [""];
               }
               $textual = array_merge($first, [""], $second);
               break;
            }
         }
         $textual = implode(':', $textual);
      }

      $prefix = "";

      //If it a special format, add prefix previsouly removed (to manage IPV4 part)
      if ($this->isDottedQuoadFormat) {
         $prefix = "::ffff:";
      }

      $this->textual = $prefix.$textual;
      return true;
   }


   /**
    * \brief add value to the address for iterator on addresses
    *
    * @param integer[] $address   (in and out) the address to increment or decrement
    * @param integer   $value     the value to add or remove. Must be betwwen -0xffffffff and +0xffffffff
    *
    * @return true if the increment is valid
   **/
   static function addValueToAddress(&$address, $value) {

      if (!is_array($address)
          || (count($address) != 4)
          || !is_numeric($value)
          || ($value < -0xffffffff)
          || ($value > 0xffffffff)) {
         return false;
      }

      for ($i = 3; $i >= 0; --$i) {
         $address[$i] += $value;
         if ($address[$i] < 0) {
            $address[$i] += (0x80000000 * 2);
            $value        = -1; // For next value for right to left ...
         } else if ($address[$i] > 0xffffffff) {
            $address[$i] -= (0x80000000 * 2);
            $value        = 1; // For next value for right to left ...
         } else {
            break;
         }
      }

      return true;
   }


   /**
    * \brief get absolute value of an integer
    * Convert a negative integer to positiv float. That is usefull as integer, in PHP are signed 32
    * bits values. As such, they are limited from +2 147 483 647 to ???2 147 483 648. Thus, when
    * working on integer with bit-wise boolean operations (&, |, ^, ~), the sign of the operand
    * remain inside the result. That make problem as IP address are only positiv ones.
    *
    * @param integer $value the integer that we want the absolute value
    *
    * @return float value that is the absolute of $value
    *
   **/
   static function convertNegativeIntegerToPositiveFloat($value) {

      if (intval($value) && ($value < 0)) {
         $value = floatval($value) + floatval(0x80000000 * 2);
      }
      return $value;
   }

   /**
    * Search IP Addresses
    *
    * @param string $IPaddress  the address to search
    *
    * @return array  each value of the array (corresponding to one IPAddress) is an array of the
    *                items from the master item to the IPAddress
   **/
   static function getItemsByIPAddress($IPaddress) {
      global $DB;

      // We must resolv binary address :
      //    1??) we don't know if the IP address is valid
      //    2??) we don't know its version
      //    3??) binary request is more efficient than textual one (polymorphism of IPv6 addresses)
      $address = new self();

      if (!$address->setAddressFromString($IPaddress)) {
         return [];
      }

      $criteria = [
         'SELECT' => 'gip.id',
         'FROM'   => 'glpi_ipaddresses AS gip',
         'WHERE'  => ['gip.version' => $address->version]
      ];
      $startIndex = (($address->version == 4) ? 3 : 1);
      $binaryIP = $address->getBinary();
      for ($i = $startIndex; $i < 4; ++$i) {
         $criteria['WHERE']["gip.binary_$i"] = $binaryIP[$i];
      }
      $iterator = $DB->request($criteria);
      $addressesWithItems = [];
      while ($result = $iterator->next()) {
         if ($address->getFromDB($result['id'])) {
            $addressesWithItems[] = array_merge(array_reverse($address->recursivelyGetItems()),
                                                [clone $address]);
         }
      }
      return $addressesWithItems;
   }


   /**
    * Get an Object ID by its IP address (only if one result is found in the entity)
    *
    * @param string  $value   the ip address
    * @param integer $entity  the entity to look for
    *
    * @return array containing the object ID
    *         or an empty array is no value of serverals ID where found
   **/
   static function getUniqueItemByIPAddress($value, $entity) {

      $addressesWithItems = self::getItemsByIPAddress($value);

      // Filter : Do not keep ip not linked to asset
      if (count($addressesWithItems)) {
         foreach ($addressesWithItems as $key => $tab) {
            if (isset($tab[0])
                && (($tab[0] instanceof NetworkName)
                    || ($tab[0] instanceof IPAddress)
                    || ($tab[0] instanceof NetworkPort)
                    || $tab[0]->isDeleted()
                    || $tab[0]->isTemplate()
                    || ($tab[0]->getEntityID() != $entity))) {
               unset($addressesWithItems[$key]);
            }
         }
      }

      if (count($addressesWithItems)) {
         // Get the first item that is matching entity
         foreach ($addressesWithItems as $items) {
            foreach ($items as $item) {
               if ($item->getEntityID() == $entity) {
                  $result = ["id"       => $item->getID(),
                                  "itemtype" => $item->getType()];
                  unset($addressesWithItems);
                  return $result;
               }
            }
         }
      }
      return [];
   }


   /**
    * Check if two addresses are equals
    *
    * @param IPAddress|string|integer[] $ipaddress  the ip address to check with this
    *
    * @return boolean true if and only if both addresses are binary equals.
   **/
   function equals($ipaddress) {

      // To normalise the address, just make new one
      $ipaddress = new self($ipaddress);

      if (!is_array($this->binary)
          || (count($this->binary) != 4)
          || (count($ipaddress->binary) != 4)
          || ($this->version != $ipaddress->version)) {
         return false;
      }

      for ($index = 0; $index < 4; $index ++) {
         if ($this->binary[$index] != $ipaddress->binary[$index]) {
            return false;
         }
      }

      return true;
   }


   /**
    * @param $itemtype
    * @param $base                  HTMLTableBase object
    * @param $super                 HTMLTableSuperHeader object (default NULL)
    * @param $father                HTMLTableHeader object (default NULL)
    * @param $options      array
   **/
   static function getHTMLTableHeader($itemtype, HTMLTableBase $base,
                                      HTMLTableSuperHeader $super = null,
                                      HTMLTableHeader $father = null, array $options = []) {

      $column_name = __CLASS__;

      $content = self::getTypeName();

      if ($itemtype == 'IPNetwork') {

         $base->addHeader('Item', _n('Item', 'Items', 1), $super, $father);
         $base->addHeader('NetworkPort', NetworkPort::getTypeName(0), $super, $father);
         $base->addHeader('NetworkName', NetworkName::getTypeName(1), $super, $father);
         $base->addHeader('Entity', Entity::getTypeName(1), $super, $father);
      } else {

         if (isset($options['dont_display'][$column_name])) {
            return;
         }

         if (isset($options['column_links'][$column_name])) {
            $content = "<a href='".$options['column_links'][$column_name]."'>$content</a>";
         }

         $father = $base->addHeader($column_name, $content, $super, $father);

         if (isset($options['display_isDynamic']) && ($options['display_isDynamic'])) {
            $father = $base->addHeader($column_name.'_dynamic', __('Automatic inventory'),
                                        $super, $father);
         }

         IPNetwork::getHTMLTableHeader(__CLASS__, $base, $super, $father, $options);
      }

   }


   /**
    * @param $row                HTMLTableRow object (default NULL)
    * @param $item               CommonDBTM object (default NULL)
    * @param $father             HTMLTableCell object (default NULL)
    * @param $options   array
   **/
   static function getHTMLTableCellsForItem(HTMLTableRow $row = null, CommonDBTM $item = null,
                                            HTMLTableCell $father = null, array $options = []) {
      global $DB, $CFG_GLPI;

      if (($item !== null)
          && ($item->getType() == 'IPNetwork')) {

         $queries = [];
         $main_criteria = [
            'SELECT'       => [
               'ADDR.binary_0 AS binary_0',
               'ADDR.binary_1 AS binary_1',
               'ADDR.binary_2 AS binary_2',
               'ADDR.binary_3 AS binary_3',
               'ADDR.name AS ip',
               'ADDR.id AS id',
               'ADDR.itemtype AS addr_item_type',
               'ADDR.items_id AS addr_item_id',
               'glpi_entities.completename AS entity',
            ],
            'FROM'         => 'glpi_ipaddresses_ipnetworks AS LINK',
            'INNER JOIN'   => [
               'glpi_ipaddresses AS ADDR' => [
                  'ON' => [
                     'ADDR'   => 'id',
                     'LINK'   => 'ipaddresses_id', [
                        'AND' => [
                           'ADDR.itemtype' => 'NetworkName',
                           'ADDR.is_deleted' => 0
                        ]
                     ]
                  ]
               ]
            ],
            'LEFT JOIN'    => [
               'glpi_entities'             => [
                  'ON' => [
                     'ADDR'            => 'entities_id',
                     'glpi_entities'   => 'id'
                  ]
               ]
            ],
            'WHERE'        => [
               'LINK.ipnetworks_id' => $item->getID(),
            ]
         ];

         foreach ($CFG_GLPI["networkport_types"] as $itemtype) {
            $table = getTableForItemType($itemtype);
            $criteria = $main_criteria;
            $criteria['SELECT'] = array_merge($criteria['SELECT'], [
               'NAME.id AS name_id',
               'PORT.id AS port_id',
               'ITEM.id AS item_id',
               new \QueryExpression("'$itemtype' AS " . $DB->quoteName('item_type'))
            ]);
            $criteria['INNER JOIN'] = $criteria['INNER JOIN'] + [
               'glpi_networknames AS NAME'   => [
                  'ON' => [
                     'NAME'   => 'id',
                     'ADDR'   => 'items_id', [
                        'AND' => [
                           'NAME.itemtype' => 'NetworkPort'
                        ]
                     ]
                  ]
               ],
               'glpi_networkports AS PORT'   => [
                  'ON' => [
                     'NAME'   => 'items_id',
                     'PORT'   => 'id', [
                        'AND' => [
                           'PORT.itemtype' => $itemtype
                        ]
                     ]
                  ]
               ],
               "$table AS ITEM"              => [
                  'ON' => [
                     'ITEM'   => 'id',
                     'PORT'   => 'items_id'
                  ]
               ]
            ];
            $queries[] = $criteria;
         }

         $criteria = $main_criteria;
         $criteria['SELECT'] = array_merge($criteria['SELECT'], [
            'NAME.id AS name_id',
            'PORT.id AS port_id',
            new \QueryExpression('NULL AS ' . $DB->quoteName('item_id')),
            new \QueryExpression("NULL AS " . $DB->quoteName('item_type')),
         ]);
         $criteria['INNER JOIN'] = $criteria['INNER JOIN'] + [
            'glpi_networknames AS NAME'   => [
               'ON' => [
                  'NAME'   => 'id',
                  'ADDR'   => 'items_id', [
                     'AND' => [
                        'NAME.itemtype' => 'NetworkPort'
                     ]
                  ]
               ]
            ],
            'glpi_networkports AS PORT'   => [
               'ON' => [
                  'NAME'   => 'items_id',
                  'PORT'   => 'id', [
                     'AND' => [
                        'NOT' => [
                           'PORT.itemtype' => $CFG_GLPI['networkport_types']
                        ]
                     ]
                  ]
               ]
            ]
         ];
         $queries[] = $criteria;

         $criteria = $main_criteria;
         $criteria['SELECT'] = array_merge($criteria['SELECT'], [
            'NAME.id AS name_id',
            new \QueryExpression("NULL AS " . $DB->quoteName('port_id')),
            new \QueryExpression('NULL AS ' . $DB->quoteName('item_id')),
            new \QueryExpression("NULL AS " . $DB->quoteName('item_type'))
         ]);
         $criteria['INNER JOIN'] = $criteria['INNER JOIN'] + [
            'glpi_networknames AS NAME'   => [
               'ON' => [
                  'NAME'   => 'id',
                  'ADDR'   => 'items_id', [
                     'AND' => [
                        'NAME.itemtype' => ['!=', 'NetworkPort']
                     ]
                  ]
               ]
            ]
         ];
         $queries[] = $criteria;

         $criteria = $main_criteria;
         $criteria['SELECT'] = array_merge($criteria['SELECT'], [
            new \QueryExpression("NULL AS name_id"),
            new \QueryExpression("NULL AS port_id"),
            new \QueryExpression('NULL AS item_id'),
            new \QueryExpression("NULL AS item_type")
         ]);
         $criteria['INNER JOIN']['glpi_ipaddresses AS ADDR']['ON'][0]['AND']['ADDR.itemtype'] = ['!=', 'NetworkName'];
         $queries[] = $criteria;

         $union = new \QueryUnion($queries);
         $criteria = [
            'FROM'   => $union,
         ];

         if (($options['order'] == 'ip')
             || ($options['order'] == 'itemtype')) {
            $criteria['ORDERBY'] = [
               'binary_0',
               'binary_1',
               'binary_2',
               'binary_3'
            ];
         }

         if (isset($options['SQL_options'])) {
            $criteria = array_merge($criteria, $options['SQL_options']);
         }
         $iterator = $DB->request($criteria);

         $canedit              = (isset($options['canedit']) && $options['canedit']);
         $options['createRow'] = false;
         $address              = new self();

         $ipaddress   = new self();
         $networkname = new NetworkName();
         $networkport = new NetworkPort();

         $item = null;
         while ($line = $iterator->next()) {
            unset($row);

            if (($options['order'] == 'itemtype')
                && !empty($line['item_type'])) {
               $row = $options['group_'.$line['item_type']]->createRow();
            }

            if (!isset($row)) {
               $row = $options['group_None']->createRow();
            }

            $ip_header  = $row->getGroup()->getSuperHeaderByName('IP Address');
            $item_header= $row->getGroup()->getHeaderByName('Item', 'Item');
            $port_header= $row->getGroup()->getHeaderByName('Item', 'NetworkPort');
            $name_header= $row->getGroup()->getHeaderByName('Item', 'NetworkName');
            $entity_header= $row->getGroup()->getHeaderByName('Item', 'Entity');

            $row->addCell($ip_header, $line['ip'], $father);

            if (!empty($line['name_id'])) {
               $networkname->getFromDB($line['name_id']);
               $row->addCell($name_header, $networkname->getLink(), $father);

               if (!empty($line['port_id'])) {
                  $networkport->getFromDB($line['port_id']);
                  $row->addCell($port_header, $networkport->getLink(), $father);

                  if ((!empty($line['item_id'])) && (!empty($line['item_type']))) {
                     $itemtype = $line['item_type'];
                     $item     = new $itemtype();
                     $item->getFromDB($line['item_id']);
                     $row->addCell($item_header, $item->getLink(), $father);
                  }
               }
               $row->addCell($entity_header, $line['entity'], $father);
            } else if ((!empty($line['addr_item_id'])) && (!empty($line['addr_item_type']))) {
               $itemtype = $line['addr_item_type'];
               $item     = new $itemtype();
               $item->getFromDB($line['addr_item_id']);
               if ($item instanceof CommonDBChild) {
                  $items    = $item->recursivelyGetItems();
                  $elements = [$item->getLink()];
                  foreach ($items as $item_) {
                     $elements[] = $item_->getLink();
                  }
                  $row->addCell($item_header, implode(' > ', $elements), $father);
               } else {
                  $row->addCell($item_header, $item->getLink(), $father);
               }
               $row->addCell($entity_header, $line['entity'], $father);
            }
         }

      } else {

         if (isset($options['dont_display']['IPAddress'])) {
            return;
         }

         $header= $row->getGroup()->getHeaderByName('Internet', __CLASS__);
         if (!$header) {
            return;
         }

         if (empty($item)) {
            if (empty($father)) {
               return;
            }
            $item = $father->getItem();
         }

         $iterator = $DB->request([
            'SELECT' => 'id',
            'FROM'   => self::getTable(),
            'WHERE'  => [
               'items_id'     => $item->getID(),
               'itemtype'     => $item->getType(),
               'is_deleted'   => 0
            ]
         ]);

         $canedit              = (isset($options['canedit']) && $options['canedit']);
         $createRow            = (isset($options['createRow']) && $options['createRow']);
         $options['createRow'] = false;
         $address              = new self();

         while ($ipaddress = $iterator->next()) {
            if ($address->getFromDB($ipaddress['id'])) {

               if ($createRow) {
                  $row = $row->createRow();
               }

               $content   = $address->fields['name'];
               $this_cell = $row->addCell($header, $content, $father);

               if (isset($options['display_isDynamic']) && ($options['display_isDynamic'])) {
                  $dyn_header = $row->getGroup()->getHeaderByName('Internet', __CLASS__.'_dynamic');
                  $this_cell  = $row->addCell($dyn_header,
                                              Dropdown::getYesNo($address->fields['is_dynamic']),
                                              $this_cell);
               }

               IPNetwork::getHTMLTableCellsForItem($row, $address, $this_cell, $options);
            }
         }
      }
   }
}
