woocommerce/includes/vendor/class-requests-ipv6.php

185 lines
4.9 KiB
PHP

<?php
/**
* Class to validate and to work with IPv6 addresses
*
* @package Requests
* @subpackage Utilities
*/
/**
* Class to validate and to work with IPv6 addresses
*
* This was originally based on the PEAR class of the same name, but has been
* entirely rewritten.
*
* @package Requests
* @subpackage Utilities
*/
class Requests_IPv6 {
/**
* Uncompresses an IPv6 address
*
* RFC 4291 allows you to compress consecutive zero pieces in an address to
* '::'. This method expects a valid IPv6 address and expands the '::' to
* the required number of zero pieces.
*
* Example: FF01::101 -> FF01:0:0:0:0:0:0:101
* ::1 -> 0:0:0:0:0:0:0:1
*
* @author Alexander Merz <alexander.merz@web.de>
* @author elfrink at introweb dot nl
* @author Josh Peck <jmp at joshpeck dot org>
* @copyright 2003-2005 The PHP Group
* @license http://www.opensource.org/licenses/bsd-license.php
* @param string $ip An IPv6 address
* @return string The uncompressed IPv6 address
*/
public static function uncompress( $ip ) {
if ( substr_count( $ip, '::' ) !== 1 ) {
return $ip;
}
list($ip1, $ip2) = explode( '::', $ip );
$c1 = ( '' == $ip1 ) ? -1 : substr_count( $ip1, ':' );
$c2 = ( '' == $ip2 ) ? -1 : substr_count( $ip2, ':' );
if ( strpos( $ip2, '.' ) !== false ) {
$c2++;
}
// ::
if ( -1 === $c1 && -1 === $c2 ) {
$ip = '0:0:0:0:0:0:0:0';
} // ::xxx
elseif ( -1 === $c1 ) {
$fill = str_repeat( '0:', 7 - $c2 );
$ip = str_replace( '::', $fill, $ip );
} // xxx::
elseif ( -1 === $c2 ) {
$fill = str_repeat( ':0', 7 - $c1 );
$ip = str_replace( '::', $fill, $ip );
} // xxx::xxx
else {
$fill = ':' . str_repeat( '0:', 6 - $c2 - $c1 );
$ip = str_replace( '::', $fill, $ip );
}
return $ip;
}
/**
* Compresses an IPv6 address
*
* RFC 4291 allows you to compress consecutive zero pieces in an address to
* '::'. This method expects a valid IPv6 address and compresses consecutive
* zero pieces to '::'.
*
* Example: FF01:0:0:0:0:0:0:101 -> FF01::101
* 0:0:0:0:0:0:0:1 -> ::1
*
* @see uncompress()
* @param string $ip An IPv6 address
* @return string The compressed IPv6 address
*/
public static function compress( $ip ) {
// Prepare the IP to be compressed
$ip = self::uncompress( $ip );
$ip_parts = self::split_v6_v4( $ip );
// Replace all leading zeros
$ip_parts[0] = preg_replace( '/(^|:)0+([0-9])/', '\1\2', $ip_parts[0] );
// Find bunches of zeros
if ( preg_match_all( '/(?:^|:)(?:0(?::|$))+/', $ip_parts[0], $matches, PREG_OFFSET_CAPTURE ) ) {
$max = 0;
$pos = null;
foreach ( $matches[0] as $match ) {
if ( strlen( $match[0] ) > $max ) {
$max = strlen( $match[0] );
$pos = $match[1];
}
}
$ip_parts[0] = substr_replace( $ip_parts[0], '::', $pos, $max );
}
if ( '' !== $ip_parts[1] ) {
return implode( ':', $ip_parts );
} else {
return $ip_parts[0];
}
}
/**
* Splits an IPv6 address into the IPv6 and IPv4 representation parts
*
* RFC 4291 allows you to represent the last two parts of an IPv6 address
* using the standard IPv4 representation
*
* Example: 0:0:0:0:0:0:13.1.68.3
* 0:0:0:0:0:FFFF:129.144.52.38
*
* @param string $ip An IPv6 address
* @return string[] [0] contains the IPv6 represented part, and [1] the IPv4 represented part
*/
protected static function split_v6_v4( $ip ) {
if ( strpos( $ip, '.' ) !== false ) {
$pos = strrpos( $ip, ':' );
$ipv6_part = substr( $ip, 0, $pos );
$ipv4_part = substr( $ip, $pos + 1 );
return array( $ipv6_part, $ipv4_part );
} else {
return array( $ip, '' );
}
}
/**
* Checks an IPv6 address
*
* Checks if the given IP is a valid IPv6 address
*
* @param string $ip An IPv6 address
* @return bool true if $ip is a valid IPv6 address
*/
public static function check_ipv6( $ip ) {
$ip = self::uncompress( $ip );
list($ipv6, $ipv4) = self::split_v6_v4( $ip );
$ipv6 = explode( ':', $ipv6 );
$ipv4 = explode( '.', $ipv4 );
if ( count( $ipv6 ) === 8 && count( $ipv4 ) === 1 || count( $ipv6 ) === 6 && count( $ipv4 ) === 4 ) {
foreach ( $ipv6 as $ipv6_part ) {
// The section can't be empty
if ( '' === $ipv6_part ) {
return false;
}
// Nor can it be over four characters
if ( strlen( $ipv6_part ) > 4 ) {
return false;
}
// Remove leading zeros (this is safe because of the above)
$ipv6_part = ltrim( $ipv6_part, '0' );
if ( '' === $ipv6_part ) {
$ipv6_part = '0';
}
// Check the value is valid
$value = hexdec( $ipv6_part );
if ( dechex( $value ) !== strtolower( $ipv6_part ) || $value < 0 || $value > 0xFFFF ) {
return false;
}
}
if ( count( $ipv4 ) === 4 ) {
foreach ( $ipv4 as $ipv4_part ) {
$value = (int) $ipv4_part;
if ( (string) $value !== $ipv4_part || $value < 0 || $value > 0xFF ) {
return false;
}
}
}
return true;
} else {
return false;
}
}
}