WordPress/wp-includes/SimplePie/Net/IPv6.php

277 lines
7.4 KiB
PHP

<?php
/**
* SimplePie
*
* A PHP-Based RSS and Atom Feed Framework.
* Takes the hard work out of managing a complete RSS/Atom solution.
*
* Copyright (c) 2004-2012, Ryan Parman, Geoffrey Sneddon, Ryan McCue, and contributors
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are
* permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice, this list
* of conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* * Neither the name of the SimplePie Team nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS
* AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* @package SimplePie
* @version 1.3.1
* @copyright 2004-2012 Ryan Parman, Geoffrey Sneddon, Ryan McCue
* @author Ryan Parman
* @author Geoffrey Sneddon
* @author Ryan McCue
* @link http://simplepie.org/ SimplePie
* @license http://www.opensource.org/licenses/bsd-license.php BSD License
*/
/**
* Class to validate and to work with IPv6 addresses.
*
* @package SimplePie
* @subpackage HTTP
* @copyright 2003-2005 The PHP Group
* @license http://www.opensource.org/licenses/bsd-license.php
* @link http://pear.php.net/package/Net_IPv6
* @author Alexander Merz <alexander.merz@web.de>
* @author elfrink at introweb dot nl
* @author Josh Peck <jmp at joshpeck dot org>
* @author Geoffrey Sneddon <geoffers@gmail.com>
*/
class SimplePie_Net_IPv6
{
/**
* Uncompresses an IPv6 address
*
* RFC 4291 allows you to compress concecutive 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)
{
$c1 = -1;
$c2 = -1;
if (substr_count($ip, '::') === 1)
{
list($ip1, $ip2) = explode('::', $ip);
if ($ip1 === '')
{
$c1 = -1;
}
else
{
$c1 = substr_count($ip1, ':');
}
if ($ip2 === '')
{
$c2 = -1;
}
else
{
$c2 = substr_count($ip2, ':');
}
if (strpos($ip2, '.') !== false)
{
$c2++;
}
// ::
if ($c1 === -1 && $c2 === -1)
{
$ip = '0:0:0:0:0:0:0:0';
}
// ::xxx
else if ($c1 === -1)
{
$fill = str_repeat('0:', 7 - $c2);
$ip = str_replace('::', $fill, $ip);
}
// xxx::
else if ($c2 === -1)
{
$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 concecutive 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 $ip An IPv6 address
* @return array [0] contains the IPv6 represented part, and [1] the IPv4 represented part
*/
private static function split_v6_v4($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;
}
}
/**
* Checks if the given IP is a valid IPv6 address
*
* @codeCoverageIgnore
* @deprecated Use {@see SimplePie_Net_IPv6::check_ipv6()} instead
* @see check_ipv6
* @param string $ip An IPv6 address
* @return bool true if $ip is a valid IPv6 address
*/
public static function checkIPv6($ip)
{
return self::check_ipv6($ip);
}
}