Fix invalid ORDER BY

[mediawiki.git] / includes / ProxyTools.php

<?php
/**
 * Functions for dealing with proxies
 */

function wfGetForwardedFor() {
        if( function_exists( 'apache_request_headers' ) ) {
                // More reliable than $_SERVER due to case and -/_ folding
                $set = apache_request_headers();
                $index = 'X-Forwarded-For';
                $index2 = 'Client-ip';
        } else {
                // Subject to spoofing with headers like X_Forwarded_For
                $set = $_SERVER;
                $index = 'HTTP_X_FORWARDED_FOR';
                $index2 = 'CLIENT-IP';
        }
        #Try a couple of headers
        if( isset( $set[$index] ) ) {
                return $set[$index];
        } else if( isset( $set[$index2] ) ) {
                return $set[$index2];
        } else {
                return null;
        }
}

function wfGetLastIPfromXFF( $xff ) {
        if ( $xff ) {
                // Avoid annoyingly long xff hacks
                $xff = substr( $xff, 0, 511 );
                // Look for the last IP, assuming they are separated by commas or spaces
                $s = ( strrpos($xff, ',') ) ? strrpos($xff, ',') : strrpos($xff, ' ');
                if ( $s !== false ) {
                        $last = trim( substr( $xff, $s + 1 ) );
                        // Make sure it is an IP
                        $m = preg_match('#\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}#', $last, $last_ip4);
                        $n = preg_match('#:(:[0-9A-Fa-f]{1,4}){1,7}|[0-9A-Fa-f]{1,4}(:{1,2}[0-9A-Fa-f]{1,4}|::$){1,7}#', $last, $last_ip6);
                        if ( $m )
                                $xff_ip = $last_ip4;
                        else if ( $n ) 
                                $xff_ip = $last_ip6;
                        else 
                                $xff_ip = null;
                } else {
                        $xff_ip = null;
                } 
        } else {
                $xff_ip = null;
        }
        return $xff_ip;
}

function wfGetClientIPfromXFF( $xff ) {
        if ( $xff ) {
                // Avoid annoyingly long xff hacks
                $xff = substr( $xff, 0, 511 );
                // Look for the first IP
                $m = preg_match('#\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}#', $xff, $first_ip);
                $n = preg_match('#:(:[0-9A-Fa-f]{1,4}){1,7}|[0-9A-Fa-f]{1,4}(:{1,2}[0-9A-Fa-f]{1,4}|::$){1,7}#', $xff, $first_ip);
                if ( $m )
                        $xff_ip = $first_ip4;
                else if ( $n ) 
                        $xff_ip = $first_ip6;
                else 
                        $xff_ip = null;
        } else {
                $xff_ip = null;
        }
        return $xff_ip;
}

function wfGetAgent() {
        if( function_exists( 'apache_request_headers' ) ) {
                // More reliable than $_SERVER due to case and -/_ folding
                $set = apache_request_headers();
                $index = 'User-Agent';
        } else {
                // Subject to spoofing with headers like X_Forwarded_For
                $set = $_SERVER;
                $index = 'HTTP_USER_AGENT';
        }
        if( isset( $set[$index] ) ) {
                return $set[$index];
        } else {
                return '';
        }
}

/** Work out the IP address based on various globals */
function wfGetIP() {
        global $wgIP;

        # Return cached result
        if ( !empty( $wgIP ) ) {
                return $wgIP;
        }

        /* collect the originating ips */
        # Client connecting to this webserver
        if ( isset( $_SERVER['REMOTE_ADDR'] ) ) {
                $ipchain = array( IP::canonicalize( $_SERVER['REMOTE_ADDR'] ) );
        } else {
                # Running on CLI?
                $ipchain = array( '127.0.0.1' );
        }
        $ip = $ipchain[0];

        # Append XFF on to $ipchain
        $forwardedFor = wfGetForwardedFor();
        if ( isset( $forwardedFor ) ) {
                $xff = array_map( 'trim', explode( ',', $forwardedFor ) );
                $xff = array_reverse( $xff );
                $ipchain = array_merge( $ipchain, $xff );
        }
        
        # Step through XFF list and find the last address in the list which is a trusted server
        # Set $ip to the IP address given by that trusted server, unless the address is not sensible (e.g. private)
        foreach ( $ipchain as $i => $curIP ) {
                $curIP = IP::canonicalize( $curIP );
                if ( wfIsTrustedProxy( $curIP ) ) {
                        if ( isset( $ipchain[$i + 1] ) && IP::isPublic( $ipchain[$i + 1] ) ) {
                                $ip = $ipchain[$i + 1];
                        }
                } else {
                        break;
                }
        }

        wfDebug( "IP: $ip\n" );
        $wgIP = $ip;
        return $ip;
}

function wfIsTrustedProxy( $ip ) {
        global $wgSquidServers, $wgSquidServersNoPurge;

        if ( in_array( $ip, $wgSquidServers ) || 
                in_array( $ip, $wgSquidServersNoPurge ) || 
                wfIsAOLProxy( $ip ) 
        ) {
                $trusted = true;
        } else {
                $trusted = false;
        }
        wfRunHooks( 'IsTrustedProxy', array( &$ip, &$trusted ) );
        return $trusted;
}

/**
 * Forks processes to scan the originating IP for an open proxy server
 * MemCached can be used to skip IPs that have already been scanned
 */
function wfProxyCheck() {
        global $wgBlockOpenProxies, $wgProxyPorts, $wgProxyScriptPath;
        global $wgUseMemCached, $wgMemc, $wgProxyMemcExpiry;
        global $wgProxyKey;

        if ( !$wgBlockOpenProxies ) {
                return;
        }

        $ip = wfGetIP();

        # Get MemCached key
        $skip = false;
        if ( $wgUseMemCached ) {
                $mcKey = wfMemcKey( 'proxy', 'ip', $ip );
                $mcValue = $wgMemc->get( $mcKey );
                if ( $mcValue ) {
                        $skip = true;
                }
        }

        # Fork the processes
        if ( !$skip ) {
                $title = SpecialPage::getTitleFor( 'Blockme' );
                $iphash = md5( $ip . $wgProxyKey );
                $url = $title->getFullURL( 'ip='.$iphash );

                foreach ( $wgProxyPorts as $port ) {
                        $params = implode( ' ', array(
                                                escapeshellarg( $wgProxyScriptPath ),
                                                escapeshellarg( $ip ),
                                                escapeshellarg( $port ),
                                                escapeshellarg( $url )
                                                ));
                        exec( "php $params &>/dev/null &" );
                }
                # Set MemCached key
                if ( $wgUseMemCached ) {
                        $wgMemc->set( $mcKey, 1, $wgProxyMemcExpiry );
                }
        }
}

/**
 * Convert a network specification in CIDR notation to an integer network and a number of bits
 */
function wfParseCIDR( $range ) {
        return IP::parseCIDR( $range );
}

/**
 * Check if an IP address is in the local proxy list
 */
function wfIsLocallyBlockedProxy( $ip ) {
        global $wgProxyList;
        $fname = 'wfIsLocallyBlockedProxy';

        if ( !$wgProxyList ) {
                return false;
        }
        wfProfileIn( $fname );

        if ( !is_array( $wgProxyList ) ) {
                # Load from the specified file
                $wgProxyList = array_map( 'trim', file( $wgProxyList ) );
        }

        if ( !is_array( $wgProxyList ) ) {
                $ret = false;
        } elseif ( array_search( $ip, $wgProxyList ) !== false ) {
                $ret = true;
        } elseif ( array_key_exists( $ip, $wgProxyList ) ) {
                # Old-style flipped proxy list
                $ret = true;
        } else {
                $ret = false;
        }
        wfProfileOut( $fname );
        return $ret;
}

/**
 * TODO: move this list to the database in a global IP info table incorporating
 * trusted ISP proxies, blocked IP addresses and open proxies.
 */
function wfIsAOLProxy( $ip ) {
        $ranges = array(
                '64.12.96.0/19',
                '149.174.160.0/20',
                '152.163.240.0/21',
                '152.163.248.0/22',
                '152.163.252.0/23',
                '152.163.96.0/22',
                '152.163.100.0/23',
                '195.93.32.0/22',
                '195.93.48.0/22',
                '195.93.64.0/19',
                '195.93.96.0/19',
                '195.93.16.0/20',
                '198.81.0.0/22',
                '198.81.16.0/20',
                '198.81.8.0/23',
                '202.67.64.128/25',
                '205.188.192.0/20',
                '205.188.208.0/23',
                '205.188.112.0/20',
                '205.188.146.144/30',
                '207.200.112.0/21',
        );

        static $parsedRanges;
        if ( is_null( $parsedRanges ) ) {
                $parsedRanges = array();
                foreach ( $ranges as $range ) {
                        $parsedRanges[] =  IP::parseRange( $range );
                }
        }

        $hex = IP::toHex( $ip );
        foreach ( $parsedRanges as $range ) {
                if ( $hex >= $range[0] && $hex <= $range[1] ) {
                        return true;
                }
        }
        return false;
}



?>