includes/ProxyTools.php

   1 <?php
   2 if ( ! defined( 'MEDIAWIKI' ) )
   3         die();
   4 /**
   5  * Functions for dealing with proxies
   6  * @package MediaWiki
   7  */
   8
   9 /** Work out the IP address based on various globals */
  10 function wfGetIP() {
  11         global $wgSquidServers, $wgSquidServersNoPurge, $wgIP;
  12
  13         # Return cached result
  14         if ( !empty( $wgIP ) ) {
  15                 return $wgIP;
  16         }
  17
  18         /* collect the originating ips */
  19         # Client connecting to this webserver
  20         if ( isset( $_SERVER['REMOTE_ADDR'] ) ) {
  21                 $ipchain = array( $_SERVER['REMOTE_ADDR'] );
  22         } else {
  23                 # Running on CLI?
  24                 $ipchain = array( '127.0.0.1' );
  25         }
  26         $ip = $ipchain[0];
  27
  28         # Get list of trusted proxies
  29         # Flipped for quicker access
  30         $trustedProxies = array_flip( array_merge( $wgSquidServers, $wgSquidServersNoPurge ) );
  31         if ( count( $trustedProxies ) ) {
  32                 # Append XFF on to $ipchain
  33                 if ( isset( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
  34                         $xff = array_map( 'trim', explode( ',', $_SERVER['HTTP_X_FORWARDED_FOR'] ) );
  35                         $xff = array_reverse( $xff );
  36                         $ipchain = array_merge( $ipchain, $xff );
  37                 }
  38                 # Step through XFF list and find the last address in the list which is a trusted server
  39                 # Set $ip to the IP address given by that trusted server, unless the address is not sensible (e.g. private)
  40                 foreach ( $ipchain as $i => $curIP ) {
  41                         if ( array_key_exists( $curIP, $trustedProxies ) ) {
  42                                 if ( isset( $ipchain[$i + 1] ) && wfIsIPPublic( $ipchain[$i + 1] ) ) {
  43                                         $ip = $ipchain[$i + 1];
  44                                 }
  45                         } else {
  46                                 break;
  47                         }
  48                 }
  49         }
  50
  51         wfDebug( "IP: $ip\n" );
  52         $wgIP = $ip;
  53         return $ip;
  54 }
  55
  56 /**
  57  * Given an IP address in dotted-quad notation, returns an unsigned integer.
  58  * Like ip2long() except that it actually works and has a consistent error return value.
  59  */
  60 function wfIP2Unsigned( $ip ) {
  61         $n = ip2long( $ip );
  62         if ( $n == -1 || $n === false ) { # Return value on error depends on PHP version
  63                 $n = false;
  64         } elseif ( $n < 0 ) {
  65                 $n += pow( 2, 32 );
  66         }
  67         return $n;
  68 }
  69
  70 /**
  71  * Return a zero-padded hexadecimal representation of an IP address
  72  */
  73 function wfIP2Hex( $ip ) {
  74         $n = wfIP2Unsigned( $ip );
  75         if ( $n !== false ) {
  76                 $n = sprintf( '%08X', $n );
  77         }
  78         return $n;
  79 }
  80
  81 /**
  82  * Determine if an IP address really is an IP address, and if it is public,
  83  * i.e. not RFC 1918 or similar
  84  */
  85 function wfIsIPPublic( $ip ) {
  86         $n = wfIP2Unsigned( $ip );
  87         if ( !$n ) {
  88                 return false;
  89         }
  90
  91         static $privateRanges = false;
  92         if ( !$privateRanges ) {
  93                 $privateRanges = array(
  94                         array( '10.0.0.0',    '10.255.255.255' ),   # RFC 1918 (private)
  95                         array( '172.16.0.0',  '172.31.255.255' ),   #     "
  96                         array( '192.168.0.0', '192.168.255.255' ),  #     "
  97                         array( '0.0.0.0',     '0.255.255.255' ),    # this network
  98                         array( '127.0.0.0',   '127.255.255.255' ),  # loopback
  99                 );
 100         }
 101
 102         foreach ( $privateRanges as $r ) {
 103                 $start = wfIP2Unsigned( $r[0] );
 104                 $end = wfIP2Unsigned( $r[1] );
 105                 if ( $n >= $start && $n <= $end ) {
 106                         return false;
 107                 }
 108         }
 109         return true;
 110 }
 111
 112 /**
 113  * Forks processes to scan the originating IP for an open proxy server
 114  * MemCached can be used to skip IPs that have already been scanned
 115  */
 116 function wfProxyCheck() {
 117         global $wgBlockOpenProxies, $wgProxyPorts, $wgProxyScriptPath;
 118         global $wgUseMemCached, $wgMemc, $wgDBname, $wgProxyMemcExpiry;
 119
 120         if ( !$wgBlockOpenProxies ) {
 121                 return;
 122         }
 123
 124         $ip = wfGetIP();
 125
 126         # Get MemCached key
 127         $skip = false;
 128         if ( $wgUseMemCached ) {
 129                 $mcKey = "$wgDBname:proxy:ip:$ip";
 130                 $mcValue = $wgMemc->get( $mcKey );
 131                 if ( $mcValue ) {
 132                         $skip = true;
 133                 }
 134         }
 135
 136         # Fork the processes
 137         if ( !$skip ) {
 138                 $title = Title::makeTitle( NS_SPECIAL, 'Blockme' );
 139                 $iphash = md5( $ip . $wgProxyKey );
 140                 $url = $title->getFullURL( 'ip='.$iphash );
 141
 142                 foreach ( $wgProxyPorts as $port ) {
 143                         $params = implode( ' ', array(
 144                                                 escapeshellarg( $wgProxyScriptPath ),
 145                                                 escapeshellarg( $ip ),
 146                                                 escapeshellarg( $port ),
 147                                                 escapeshellarg( $url )
 148                                                 ));
 149                         exec( "php $params &>/dev/null &" );
 150                 }
 151                 # Set MemCached key
 152                 if ( $wgUseMemCached ) {
 153                         $wgMemc->set( $mcKey, 1, $wgProxyMemcExpiry );
 154                 }
 155         }
 156 }
 157
 158 /**
 159  * Convert a network specification in CIDR notation to an integer network and a number of bits
 160  */
 161 function wfParseCIDR( $range ) {
 162         $parts = explode( '/', $range, 2 );
 163         if ( count( $parts ) != 2 ) {
 164                 return array( false, false );
 165         }
 166         $network = wfIP2Unsigned( $parts[0] );
 167         if ( $network !== false && is_numeric( $parts[1] ) && $parts[1] >= 0 && $parts[1] <= 32 ) {
 168                 $bits = $parts[1];
 169         } else {
 170                 $network = false;
 171                 $bits = false;
 172         }
 173         return array( $network, $bits );
 174 }
 175
 176 /**
 177  * Check if an IP address is in the local proxy list
 178  */
 179 function wfIsLocallyBlockedProxy( $ip ) {
 180         global $wgProxyList;
 181         $fname = 'wfIsLocallyBlockedProxy';
 182
 183         if ( !$wgProxyList ) {
 184                 return false;
 185         }
 186         wfProfileIn( $fname );
 187
 188         if ( !is_array( $wgProxyList ) ) {
 189                 # Load from the specified file
 190                 $wgProxyList = array_map( 'trim', file( $wgProxyList ) );
 191         }
 192
 193         if ( !is_array( $wgProxyList ) ) {
 194                 $ret = false;
 195         } elseif ( array_search( $ip, $wgProxyList ) !== false ) {
 196                 $ret = true;
 197         } elseif ( array_key_exists( $ip, $wgProxyList ) ) {
 198                 # Old-style flipped proxy list
 199                 $ret = true;
 200         } else {
 201                 $ret = false;
 202         }
 203         wfProfileOut( $fname );
 204         return $ret;
 205 }
 206
 207
 208
 209
 210 ?>