inc/classes/resolver.class.php

   1 <?php
   2 /************************************************************************
   3  * Mailer v0.2.1-FINAL                                Start: 03/05/2010 *
   4  * ===================                          Last change: 03/05/2010 *
   5  *                                                                      *
   6  * -------------------------------------------------------------------- *
   7  * File              : resolver.class.php                               *
   8  * -------------------------------------------------------------------- *
   9  * Short description : Resolver class                                   *
  10  * -------------------------------------------------------------------- *
  11  * Kurzbeschreibung  : Resolver-Klasse                                  *
  12  * -------------------------------------------------------------------- *
  13  * Copyright (c) 2003 - 2009 by Roland Haeder                           *
  14  * Copyright (c) 2009 - 2015 by Mailer Developer Team                   *
  15  * For more information visit: http://mxchange.org                      *
  16  *                                                                      *
  17  * This program is free software; you can redistribute it and/or modify *
  18  * it under the terms of the GNU General Public License as published by *
  19  * the Free Software Foundation; either version 2 of the License, or    *
  20  * (at your option) any later version.                                  *
  21  *                                                                      *
  22  * This program is distributed in the hope that it will be useful,      *
  23  * but WITHOUT ANY WARRANTY; without even the implied warranty of       *
  24  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        *
  25  * GNU General Public License for more details.                         *
  26  *                                                                      *
  27  * You should have received a copy of the GNU General Public License    *
  28  * along with this program; if not, write to the Free Software          *
  29  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,               *
  30  * MA  02110-1301  USA                                                  *
  31  ************************************************************************/
  32
  33 // Some security stuff...
  34 if (!defined('__SECURITY')) {
  35         die();
  36 } // END - if
  37
  38 // Resolver class for cached hostname -> IP address resolving
  39 class HostnameResolver {
  40         // Resolve hostname -> IP address
  41         function resolveHostname ($hostname) {
  42                 // If ext-sql_patches is not at least 0.7.0, abort here and return the hostname (gethostbyname() may return something unwanted)
  43                 if (!isExtensionInstalledAndNewer('sql_patches', '0.7.0')) {
  44                         // Abort here
  45                         return $hostname;
  46                 } // END - if
  47
  48                 // Prepare hostname, look for the ':port' part
  49                 $hostArray = explode(':', $hostname, 2);
  50                 $hostname = strtolower($hostArray[0]);
  51
  52                 // Is the hostname an IP address?
  53                 if (preg_match('/(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9])\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[0-9])/', $hostname, $matches)) {
  54                         // Then we don't need to look it up
  55                         //* DEBUG: */ logDebugMessage(__METHOD__, __LINE__, sprintf("Hostname %s is an IP address. No need to lookup.", $hostname));
  56                         return $hostname;
  57                 } // END - if
  58
  59                 // Log entry
  60                 //* DEBUG: */ logDebugMessage(__METHOD__, __LINE__, sprintf("Begin lookup: %s", $hostname));
  61                 $ret = '0.0.0.0';
  62
  63                 // Search for hostname in cache
  64                 $result = sqlQueryEscaped("SELECT `ip` FROM `{?_MYSQL_PREFIX?}_dns_cache` WHERE `hostname`='%s' LIMIT 1",
  65                         array(
  66                                 $hostname
  67                         ), __METHOD__, __LINE__
  68                 );
  69
  70                 // Does an entry exist?
  71                 if (sqlNumRows($result) == 1) {
  72                         // Then load the hostname
  73                         list($ip) = sqlFetchRow($result);
  74
  75                         // Count cache hit
  76                         incrementStatsEntry('dns_cache_hits');
  77
  78                         // Set fetched IP number as return value
  79                         $ret = $ip;
  80                         //* DEBUG: */ logDebugMessage(__METHOD__, __LINE__, sprintf("Cache used: %s->%s", $hostname, $ip));
  81                 } else {
  82                         // Get IP address
  83                         $ip = gethostbyname($hostname);
  84                         //* DEBUG: */ logDebugMessage(__METHOD__, __LINE__, 'ip=' . $ip . ',hostname=' . $hostname . ' - RESOLVED!');
  85
  86                         // Count lookup hit
  87                         incrementStatsEntry('dns_lookup_hits');
  88
  89                         // Is it an IP address?
  90                         if (($ip != $hostname) && (preg_match('/(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9])\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[0-9])/', $ip, $matches))) {
  91                                 // Seems to be an IP! Now check deeper...
  92                                 if (($matches[0] == $ip) && ($matches[1] >= 0) && ($matches[1] <= 255) && ($matches[2] >= 0) && ($matches[2] <= 255) && ($matches[3] >= 0) && ($matches[3] <= 255) && ($matches[4] > 0) && ($matches[4] < 255)) {
  93                                         // We also cache IP addresses
  94                                         sqlQueryEscaped("INSERT INTO `{?_MYSQL_PREFIX?}_dns_cache` (`ip`, `hostname`, `added`) VALUES ('%s', '%s', NOW())",
  95                                                 array(
  96                                                         $ip,
  97                                                         $hostname
  98                                                 ), __METHOD__, __LINE__
  99                                         );
 100
 101                                         // Set return value to $ip
 102                                         //* DEBUG: */ logDebugMessage(__METHOD__, __LINE__, sprintf("IP detected, cache entry written: %s->%s", $hostname, $ip));
 103                                         $ret = $ip;
 104                                 } else {
 105                                         // Network address or broadcast address found
 106                                         //* DEBUG: */ logDebugMessage(__METHOD__, __LINE__, sprintf("IP %s is possibly a network or broadcast address.", $ip));
 107                                 }
 108                         } elseif ($ip == $hostname) {
 109                                 // Nothing found, maybe invalid!
 110                                 //* DEBUG: */ logDebugMessage(__METHOD__, __LINE__, sprintf("Cannot lookup: %s", $hostname));
 111                         } else {
 112                                 // Put entry in DB
 113                                 sqlQueryEscaped("INSERT INTO `{?_MYSQL_PREFIX?}_dns_cache` (`ip`, `hostname`, `added`) VALUES ('%s', '%s', NOW())",
 114                                         array(
 115                                                 $ip,
 116                                                 $hostname
 117                                         ), __METHOD__, __LINE__
 118                                 );
 119
 120                                 // Set return value to $ip
 121                                 $ret = $ip;
 122                                 //* DEBUG: */ logDebugMessage(__METHOD__, __LINE__, sprintf("Lookup successfull, cache entry written: %s->%s", $hostname, $ip));
 123                         }
 124                 }
 125
 126                 // Free result
 127                 sqlFreeResult($result);
 128
 129                 // Return IP number (let's hope it)
 130                 return $ret;
 131         }
 132
 133         // Purge old entries
 134         function purgeEntries() {
 135                 // SQL for cleaning up
 136                 sqlQuery('DELETE LOW_PRIORITY FROM `{?_MYSQL_PREFIX?}_dns_cache` WHERE (UNIX_TIMESTAMP() - UNIX_TIMESTAMP(`added`) >= {?dns_cache_timeout?})',
 137                         __METHOD__, __LINE__);
 138         }
 139 }
 140
 141 // [EOF]
 142 ?>