includes/ProxyTools.php

   1 <?php
   2 /**
   3  * Functions for dealing with proxies
   4  * @package MediaWiki
   5  */
   6
   7 function wfGetForwardedFor() {
   8         if( function_exists( 'apache_request_headers' ) ) {
   9                 // More reliable than $_SERVER due to case and -/_ folding
  10                 $set = apache_request_headers();
  11                 $index = 'X-Forwarded-For';
  12         } else {
  13                 // Subject to spoofing with headers like X_Forwarded_For
  14                 $set = $_SERVER;
  15                 $index = 'HTTP_X_FORWARDED_FOR';
  16         }
  17         if( isset( $set[$index] ) ) {
  18                 return $set[$index];
  19         } else {
  20                 return null;
  21         }
  22 }
  23
  24 /** Work out the IP address based on various globals */
  25 function wfGetIP() {
  26         global $wgIP;
  27
  28         # Return cached result
  29         if ( !empty( $wgIP ) ) {
  30                 return $wgIP;
  31         }
  32
  33         /* collect the originating ips */
  34         # Client connecting to this webserver
  35         if ( isset( $_SERVER['REMOTE_ADDR'] ) ) {
  36                 $ipchain = array( $_SERVER['REMOTE_ADDR'] );
  37         } else {
  38                 # Running on CLI?
  39                 $ipchain = array( '127.0.0.1' );
  40         }
  41         $ip = $ipchain[0];
  42
  43         # Append XFF on to $ipchain
  44         $forwardedFor = wfGetForwardedFor();
  45         if ( isset( $forwardedFor ) ) {
  46                 $xff = array_map( 'trim', explode( ',', $forwardedFor ) );
  47                 $xff = array_reverse( $xff );
  48                 $ipchain = array_merge( $ipchain, $xff );
  49         }
  50         # Step through XFF list and find the last address in the list which is a trusted server
  51         # Set $ip to the IP address given by that trusted server, unless the address is not sensible (e.g. private)
  52         foreach ( $ipchain as $i => $curIP ) {
  53                 if ( wfIsTrustedProxy( $curIP ) ) {
  54                         if ( isset( $ipchain[$i + 1] ) && IP::isPublic( $ipchain[$i + 1] ) ) {
  55                                 $ip = $ipchain[$i + 1];
  56                         }
  57                 } else {
  58                         break;
  59                 }
  60         }
  61
  62         wfDebug( "IP: $ip\n" );
  63         $wgIP = $ip;
  64         return $ip;
  65 }
  66
  67 function wfIsTrustedProxy( $ip ) {
  68         global $wgSquidServers, $wgSquidServersNoPurge;
  69
  70         if ( in_array( $ip, $wgSquidServers ) ||
  71                 in_array( $ip, $wgSquidServersNoPurge ) ||
  72                 wfIsAOLProxy( $ip )
  73         ) {
  74                 $trusted = true;
  75         } else {
  76                 $trusted = false;
  77         }
  78         wfRunHooks( 'IsTrustedProxy', array( &$ip, &$trusted ) );
  79         return $trusted;
  80 }
  81
  82 /**
  83  * Forks processes to scan the originating IP for an open proxy server
  84  * MemCached can be used to skip IPs that have already been scanned
  85  */
  86 function wfProxyCheck() {
  87         global $wgBlockOpenProxies, $wgProxyPorts, $wgProxyScriptPath;
  88         global $wgUseMemCached, $wgMemc, $wgProxyMemcExpiry;
  89         global $wgProxyKey;
  90
  91         if ( !$wgBlockOpenProxies ) {
  92                 return;
  93         }
  94
  95         $ip = wfGetIP();
  96
  97         # Get MemCached key
  98         $skip = false;
  99         if ( $wgUseMemCached ) {
 100                 $mcKey = wfMemcKey( 'proxy', 'ip', $ip );
 101                 $mcValue = $wgMemc->get( $mcKey );
 102                 if ( $mcValue ) {
 103                         $skip = true;
 104                 }
 105         }
 106
 107         # Fork the processes
 108         if ( !$skip ) {
 109                 $title = SpecialPage::getTitleFor( 'Blockme' );
 110                 $iphash = md5( $ip . $wgProxyKey );
 111                 $url = $title->getFullURL( 'ip='.$iphash );
 112
 113                 foreach ( $wgProxyPorts as $port ) {
 114                         $params = implode( ' ', array(
 115                                                 escapeshellarg( $wgProxyScriptPath ),
 116                                                 escapeshellarg( $ip ),
 117                                                 escapeshellarg( $port ),
 118                                                 escapeshellarg( $url )
 119                                                 ));
 120                         exec( "php $params &>/dev/null &" );
 121                 }
 122                 # Set MemCached key
 123                 if ( $wgUseMemCached ) {
 124                         $wgMemc->set( $mcKey, 1, $wgProxyMemcExpiry );
 125                 }
 126         }
 127 }
 128
 129 /**
 130  * Convert a network specification in CIDR notation to an integer network and a number of bits
 131  */
 132 function wfParseCIDR( $range ) {
 133         return IP::parseCIDR( $range );
 134 }
 135
 136 /**
 137  * Check if an IP address is in the local proxy list
 138  */
 139 function wfIsLocallyBlockedProxy( $ip ) {
 140         global $wgProxyList;
 141         $fname = 'wfIsLocallyBlockedProxy';
 142
 143         if ( !$wgProxyList ) {
 144                 return false;
 145         }
 146         wfProfileIn( $fname );
 147
 148         if ( !is_array( $wgProxyList ) ) {
 149                 # Load from the specified file
 150                 $wgProxyList = array_map( 'trim', file( $wgProxyList ) );
 151         }
 152
 153         if ( !is_array( $wgProxyList ) ) {
 154                 $ret = false;
 155         } elseif ( array_search( $ip, $wgProxyList ) !== false ) {
 156                 $ret = true;
 157         } elseif ( array_key_exists( $ip, $wgProxyList ) ) {
 158                 # Old-style flipped proxy list
 159                 $ret = true;
 160         } else {
 161                 $ret = false;
 162         }
 163         wfProfileOut( $fname );
 164         return $ret;
 165 }
 166
 167 /**
 168  * TODO: move this list to the database in a global IP info table incorporating
 169  * trusted ISP proxies, blocked IP addresses and open proxies.
 170  */
 171 function wfIsAOLProxy( $ip ) {
 172         $ranges = array(
 173                 '64.12.96.0/19',
 174                 '149.174.160.0/20',
 175                 '152.163.240.0/21',
 176                 '152.163.248.0/22',
 177                 '152.163.252.0/23',
 178                 '152.163.96.0/22',
 179                 '152.163.100.0/23',
 180                 '195.93.32.0/22',
 181                 '195.93.48.0/22',
 182                 '195.93.64.0/19',
 183                 '195.93.96.0/19',
 184                 '195.93.16.0/20',
 185                 '198.81.0.0/22',
 186                 '198.81.16.0/20',
 187                 '198.81.8.0/23',
 188                 '202.67.64.128/25',
 189                 '205.188.192.0/20',
 190                 '205.188.208.0/23',
 191                 '205.188.112.0/20',
 192                 '205.188.146.144/30',
 193                 '207.200.112.0/21',
 194         );
 195
 196         static $parsedRanges;
 197         if ( is_null( $parsedRanges ) ) {
 198                 $parsedRanges = array();
 199                 foreach ( $ranges as $range ) {
 200                         $parsedRanges[] =  IP::parseRange( $range );
 201                 }
 202         }
 203
 204         $hex = IP::toHex( $ip );
 205         foreach ( $parsedRanges as $range ) {
 206                 if ( $hex >= $range[0] && $hex <= $range[1] ) {
 207                         return true;
 208                 }
 209         }
 210         return false;
 211 }
 212
 213
 214
 215 ?>