wiki.techinc.nl/includes/IP.php

118 lines
3.1 KiB
PHP

<?php
/*
* Collection of public static functions to play with IP address
* and IP blocks.
*
* @Author "Ashar Voultoiz" <hashar@altern.org>
* @License GPL v2 or later
*/
class IP {
// Some regex definition to "play" with IP address and IP address blocks
// An IP is made of 4 bytes from x00 to xFF which is d0 to d255
const RE_BYTE = '(25[0-5]|2[0-4]\d|1?\d{1,2})';
const RE_ADD = self::RE_BYTE . '\.' . self::RE_BYTE . '\.' . self::RE_BYTE . '\.' . self::RE_BYTE;
// An IP block is an IP address and a prefix (d1 to d32)
const RE_PREFIX = '(3[0-2]|[12]?\d)';
const RE_BLOCK = self::RE_ADD . '\/' . self::RE_PREFIX;
/**
* Validate an IP address.
* @return boolean True if it is valid.
*/
public static function isValid( $ip ) {
return preg_match( '/^' . self::RE_ADD . '$/', $ip, $matches) ;
}
/**
* Validate an IP Block.
* @return boolean True if it is valid.
*/
public static function isValidBlock( $ipblock ) {
return ( count(self::toArray($ipblock)) == 1 + 5 );
}
/**
* Determine if an IP address really is an IP address, and if it is public,
* i.e. not RFC 1918 or similar
* Comes from ProxyTools.php
*/
function isPublic( $ip ) {
$n = IP::toUnsigned( $ip );
if ( !$n ) {
return false;
}
// ip2long accepts incomplete addresses, as well as some addresses
// followed by garbage characters. Check that it's really valid.
if( $ip != long2ip( $n ) ) {
return false;
}
static $privateRanges = false;
if ( !$privateRanges ) {
$privateRanges = array(
array( '10.0.0.0', '10.255.255.255' ), # RFC 1918 (private)
array( '172.16.0.0', '172.31.255.255' ), # "
array( '192.168.0.0', '192.168.255.255' ), # "
array( '0.0.0.0', '0.255.255.255' ), # this network
array( '127.0.0.0', '127.255.255.255' ), # loopback
);
}
foreach ( $privateRanges as $r ) {
$start = IP::toUnsigned( $r[0] );
$end = IP::toUnsigned( $r[1] );
if ( $n >= $start && $n <= $end ) {
return false;
}
}
return true;
}
/**
* Split out an IP block as an array of 4 bytes and a mask,
* return false if it cant be determined
*
* @parameter $ip string A quad dotted IP address
* @return array
*/
public static function toArray( $ipblock ) {
if(! preg_match( '/^' . self::RE_ADD . '(?:\/(?:'.self::RE_PREFIX.'))?' . '$/', $ipblock, $matches ) ) {
return false;
} else {
return $matches;
}
}
/**
* Return a zero-padded hexadecimal representation of an IP address
* Comes from ProxyTools.php
* @param $ip Quad dotted IP address.
*/
public static function toHex( $ip ) {
$n = self::toUnsigned( $ip );
if ( $n !== false ) {
$n = sprintf( '%08X', $n );
}
return $n;
}
/**
* Given an IP address in dotted-quad notation, returns an unsigned integer.
* Like ip2long() except that it actually works and has a consistent error return value.
* Comes from ProxyTools.php
* @param $ip Quad dotted IP address.
*/
public static function toUnsigned( $ip ) {
$n = ip2long( $ip );
if ( $n == -1 || $n === false ) { # Return value on error depends on PHP version
$n = false;
} elseif ( $n < 0 ) {
$n += pow( 2, 32 );
}
return $n;
}
}
?>