libraries/ip_allow_deny.lib.php

   1 <?php
   2 /* vim: set expandtab sw=4 ts=4 sts=4: */
   3 /**
   4  * This library is used with the server IP allow/deny host authentication
   5  * feature
   6  *
   7  * @package phpMyAdmin
   8  */
   9
  10
  11 /**
  12  * Gets the "true" IP address of the current user
  13  *
  14  * @return  string   the ip of the user
  15  *
  16  * @access  private
  17  */
  18 function PMA_getIp()
  19 {
  20     /* Get the address of user */
  21     if (!empty($_SERVER['REMOTE_ADDR'])) {
  22         $direct_ip = $_SERVER['REMOTE_ADDR'];
  23     } else {
  24         /* We do not know remote IP */
  25         return false;
  26     }
  27
  28     /* Do we trust this IP as a proxy? If yes we will use it's header. */
  29     if (isset($GLOBALS['cfg']['TrustedProxies'][$direct_ip])) {
  30         $trusted_header_value = PMA_getenv($GLOBALS['cfg']['TrustedProxies'][$direct_ip]);
  31         $matches = array();
  32         // the $ checks that the header contains only one IP address, ?: makes sure the () don't capture
  33         $is_ip = preg_match('|^(?:[0-9]{1,3}\.){3,3}[0-9]{1,3}$|', $trusted_header_value, $matches);
  34         if ($is_ip && (count($matches) == 1)) {
  35             // True IP behind a proxy
  36             return $matches[0];
  37         }
  38     }
  39
  40     /* Return true IP */
  41     return $direct_ip;
  42 } // end of the 'PMA_getIp()' function
  43
  44
  45 /**
  46  * Based on IP Pattern Matcher
  47  * Originally by J.Adams <jna@retina.net>
  48  * Found on <http://www.php.net/manual/en/function.ip2long.php>
  49  * Modified for phpMyAdmin
  50  *
  51  * Matches:
  52  * xxx.xxx.xxx.xxx        (exact)
  53  * xxx.xxx.xxx.[yyy-zzz]  (range)
  54  * xxx.xxx.xxx.xxx/nn     (CIDR)
  55  *
  56  * Does not match:
  57  * xxx.xxx.xxx.xx[yyy-zzz]  (range, partial octets not supported)
  58  *
  59  * @param   string   string of IP range to match
  60  * @param   string   string of IP to test against range
  61  *
  62  * @return  boolean    always true
  63  *
  64  * @access  public
  65  */
  66 function PMA_ipMaskTest($testRange, $ipToTest)
  67 {
  68    $result = true;
  69
  70    if (preg_match('|([0-9]+)\.([0-9]+)\.([0-9]+)\.([0-9]+)/([0-9]+)|', $testRange, $regs)) {
  71        // performs a mask match
  72        $ipl    = ip2long($ipToTest);
  73        $rangel = ip2long($regs[1] . '.' . $regs[2] . '.' . $regs[3] . '.' . $regs[4]);
  74
  75        $maskl  = 0;
  76
  77        for ($i = 0; $i < 31; $i++) {
  78            if ($i < $regs[5] - 1) {
  79                $maskl = $maskl + PMA_pow(2, (30 - $i));
  80            } // end if
  81        } // end for
  82
  83        if (($maskl & $rangel) == ($maskl & $ipl)) {
  84            return true;
  85        } else {
  86            return false;
  87        }
  88    } else {
  89        // range based
  90        $maskocts = explode('.', $testRange);
  91        $ipocts   = explode('.', $ipToTest);
  92
  93        // perform a range match
  94        for ($i = 0; $i < 4; $i++) {
  95             if (preg_match('|\[([0-9]+)\-([0-9]+)\]|', $maskocts[$i], $regs)) {
  96                 if (($ipocts[$i] > $regs[2])
  97                     || ($ipocts[$i] < $regs[1])) {
  98                     $result = false;
  99                 } // end if
 100             } else {
 101                 if ($maskocts[$i] <> $ipocts[$i]) {
 102                     $result = false;
 103                 } // end if
 104             } // end if/else
 105        } //end for
 106    } //end if/else
 107
 108    return $result;
 109 } // end of the "PMA_IPMaskTest()" function
 110
 111
 112 /**
 113  * Runs through IP Allow/Deny rules the use of it below for more information
 114  *
 115  * @param   string 'allow' | 'deny' type of rule to match
 116  *
 117  * @return  bool   Matched a rule ?
 118  *
 119  * @access  public
 120  *
 121  * @see     PMA_getIp()
 122  */
 123 function PMA_allowDeny($type)
 124 {
 125     global $cfg;
 126
 127     // Grabs true IP of the user and returns if it can't be found
 128     $remote_ip = PMA_getIp();
 129     if (empty($remote_ip)) {
 130         return false;
 131     }
 132
 133     // copy username
 134     $username  = $cfg['Server']['user'];
 135
 136     // copy rule database
 137     $rules     = $cfg['Server']['AllowDeny']['rules'];
 138
 139     // lookup table for some name shortcuts
 140     $shortcuts = array(
 141         'all'       => '0.0.0.0/0',
 142         'localhost' => '127.0.0.1/8'
 143     );
 144
 145     // Provide some useful shortcuts if server gives us address:
 146     if (PMA_getenv('SERVER_ADDR')) {
 147         $shortcuts['localnetA'] = PMA_getenv('SERVER_ADDR') . '/8';
 148         $shortcuts['localnetB'] = PMA_getenv('SERVER_ADDR') . '/16';
 149         $shortcuts['localnetC'] = PMA_getenv('SERVER_ADDR') . '/24';
 150     }
 151
 152     foreach ($rules as $rule) {
 153         // extract rule data
 154         $rule_data = explode(' ', $rule);
 155
 156         // check for rule type
 157         if ($rule_data[0] != $type) {
 158             continue;
 159         }
 160
 161         // check for username
 162         if (($rule_data[1] != '%') //wildcarded first
 163             && ($rule_data[1] != $username)) {
 164             continue;
 165         }
 166
 167         // check if the config file has the full string with an extra
 168         // 'from' in it and if it does, just discard it
 169         if ($rule_data[2] == 'from') {
 170             $rule_data[2] = $rule_data[3];
 171         }
 172
 173         // Handle shortcuts with above array
 174         if (isset($shortcuts[$rule_data[2]])) {
 175             $rule_data[2] = $shortcuts[$rule_data[2]];
 176         }
 177
 178         // Add code for host lookups here
 179         // Excluded for the moment
 180
 181         // Do the actual matching now
 182         if (PMA_ipMaskTest($rule_data[2], $remote_ip)) {
 183             return true;
 184         }
 185     } // end while
 186
 187     return false;
 188 } // end of the "PMA_AllowDeny()" function
 189
 190 ?>