1 <?php

     2 

     3 /**

     4  * SimplePie

     5  *

     6  * A PHP-Based RSS and Atom Feed Framework.

     7  * Takes the hard work out of managing a complete RSS/Atom solution.

     8  *

     9  * Copyright (c) 2004-2022, Ryan Parman, Sam Sneddon, Ryan McCue, and contributors

    10  * All rights reserved.

    11  *

    12  * Redistribution and use in source and binary forms, with or without modification, are

    13  * permitted provided that the following conditions are met:

    14  *

    15  * 	* Redistributions of source code must retain the above copyright notice, this list of

    16  * 	  conditions and the following disclaimer.

    17  *

    18  * 	* Redistributions in binary form must reproduce the above copyright notice, this list

    19  * 	  of conditions and the following disclaimer in the documentation and/or other materials

    20  * 	  provided with the distribution.

    21  *

    22  * 	* Neither the name of the SimplePie Team nor the names of its contributors may be used

    23  * 	  to endorse or promote products derived from this software without specific prior

    24  * 	  written permission.

    25  *

    26  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS

    27  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY

    28  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS

    29  * AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

    30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

    31  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

    32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR

    33  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

    34  * POSSIBILITY OF SUCH DAMAGE.

    35  *

    36  * @package SimplePie

    37  * @copyright 2004-2016 Ryan Parman, Sam Sneddon, Ryan McCue

    38  * @author Ryan Parman

    39  * @author Sam Sneddon

    40  * @author Ryan McCue

    41  * @link http://simplepie.org/ SimplePie

    42  * @license http://www.opensource.org/licenses/bsd-license.php BSD License

    43  */

    44 

    45 namespace SimplePie\Net;

    46 

    47 /**

    48  * Class to validate and to work with IPv6 addresses.

    49  *

    50  * @package SimplePie

    51  * @subpackage HTTP

    52  * @copyright 2003-2005 The PHP Group

    53  * @license http://www.opensource.org/licenses/bsd-license.php

    54  * @link http://pear.php.net/package/Net_IPv6

    55  * @author Alexander Merz <alexander.merz@web.de>

    56  * @author elfrink at introweb dot nl

    57  * @author Josh Peck <jmp at joshpeck dot org>

    58  * @author Sam Sneddon <geoffers@gmail.com>

    59  */

    60 class IPv6

    61 {

    62     /**

    63      * Uncompresses an IPv6 address

    64      *

    65      * RFC 4291 allows you to compress concecutive zero pieces in an address to

    66      * '::'. This method expects a valid IPv6 address and expands the '::' to

    67      * the required number of zero pieces.

    68      *

    69      * Example:  FF01::101   ->  FF01:0:0:0:0:0:0:101

    70      *           ::1         ->  0:0:0:0:0:0:0:1

    71      *

    72      * @author Alexander Merz <alexander.merz@web.de>

    73      * @author elfrink at introweb dot nl

    74      * @author Josh Peck <jmp at joshpeck dot org>

    75      * @copyright 2003-2005 The PHP Group

    76      * @license http://www.opensource.org/licenses/bsd-license.php

    77      * @param string $ip An IPv6 address

    78      * @return string The uncompressed IPv6 address

    79      */

    80     public static function uncompress($ip)

    81     {

    82         $c1 = -1;

    83         $c2 = -1;

    84         if (substr_count($ip, '::') === 1) {

    85             [$ip1, $ip2] = explode('::', $ip);

    86             if ($ip1 === '') {

    87                 $c1 = -1;

    88             } else {

    89                 $c1 = substr_count($ip1, ':');

    90             }

    91             if ($ip2 === '') {

    92                 $c2 = -1;

    93             } else {

    94                 $c2 = substr_count($ip2, ':');

    95             }

    96             if (strpos($ip2, '.') !== false) {

    97                 $c2++;

    98             }

    99             // ::

   100             if ($c1 === -1 && $c2 === -1) {

   101                 $ip = '0:0:0:0:0:0:0:0';

   102             }

   103             // ::xxx

   104             elseif ($c1 === -1) {

   105                 $fill = str_repeat('0:', 7 - $c2);

   106                 $ip = str_replace('::', $fill, $ip);

   107             }

   108             // xxx::

   109             elseif ($c2 === -1) {

   110                 $fill = str_repeat(':0', 7 - $c1);

   111                 $ip = str_replace('::', $fill, $ip);

   112             }

   113             // xxx::xxx

   114             else {

   115                 $fill = ':' . str_repeat('0:', 6 - $c2 - $c1);

   116                 $ip = str_replace('::', $fill, $ip);

   117             }

   118         }

   119         return $ip;

   120     }

   121 

   122     /**

   123      * Compresses an IPv6 address

   124      *

   125      * RFC 4291 allows you to compress concecutive zero pieces in an address to

   126      * '::'. This method expects a valid IPv6 address and compresses consecutive

   127      * zero pieces to '::'.

   128      *

   129      * Example:  FF01:0:0:0:0:0:0:101   ->  FF01::101

   130      *           0:0:0:0:0:0:0:1        ->  ::1

   131      *

   132      * @see uncompress()

   133      * @param string $ip An IPv6 address

   134      * @return string The compressed IPv6 address

   135      */

   136     public static function compress($ip)

   137     {

   138         // Prepare the IP to be compressed

   139         $ip = self::uncompress($ip);

   140         $ip_parts = self::split_v6_v4($ip);

   141 

   142         // Replace all leading zeros

   143         $ip_parts[0] = preg_replace('/(^|:)0+([0-9])/', '\1\2', $ip_parts[0]);

   144 

   145         // Find bunches of zeros

   146         if (preg_match_all('/(?:^|:)(?:0(?::|$))+/', $ip_parts[0], $matches, PREG_OFFSET_CAPTURE)) {

   147             $max = 0;

   148             $pos = null;

   149             foreach ($matches[0] as $match) {

   150                 if (strlen($match[0]) > $max) {

   151                     $max = strlen($match[0]);

   152                     $pos = $match[1];

   153                 }

   154             }

   155 

   156             $ip_parts[0] = substr_replace($ip_parts[0], '::', $pos, $max);

   157         }

   158 

   159         if ($ip_parts[1] !== '') {

   160             return implode(':', $ip_parts);

   161         }

   162 

   163         return $ip_parts[0];

   164     }

   165 

   166     /**

   167      * Splits an IPv6 address into the IPv6 and IPv4 representation parts

   168      *

   169      * RFC 4291 allows you to represent the last two parts of an IPv6 address

   170      * using the standard IPv4 representation

   171      *

   172      * Example:  0:0:0:0:0:0:13.1.68.3

   173      *           0:0:0:0:0:FFFF:129.144.52.38

   174      *

   175      * @param string $ip An IPv6 address

   176      * @return array [0] contains the IPv6 represented part, and [1] the IPv4 represented part

   177      */

   178     private static function split_v6_v4($ip)

   179     {

   180         if (strpos($ip, '.') !== false) {

   181             $pos = strrpos($ip, ':');

   182             $ipv6_part = substr($ip, 0, $pos);

   183             $ipv4_part = substr($ip, $pos + 1);

   184             return [$ipv6_part, $ipv4_part];

   185         }

   186 

   187         return [$ip, ''];

   188     }

   189 

   190     /**

   191      * Checks an IPv6 address

   192      *

   193      * Checks if the given IP is a valid IPv6 address

   194      *

   195      * @param string $ip An IPv6 address

   196      * @return bool true if $ip is a valid IPv6 address

   197      */

   198     public static function check_ipv6($ip)

   199     {

   200         $ip = self::uncompress($ip);

   201         [$ipv6, $ipv4] = self::split_v6_v4($ip);

   202         $ipv6 = explode(':', $ipv6);

   203         $ipv4 = explode('.', $ipv4);

   204         if (count($ipv6) === 8 && count($ipv4) === 1 || count($ipv6) === 6 && count($ipv4) === 4) {

   205             foreach ($ipv6 as $ipv6_part) {

   206                 // The section can't be empty

   207                 if ($ipv6_part === '') {

   208                     return false;

   209                 }

   210 

   211                 // Nor can it be over four characters

   212                 if (strlen($ipv6_part) > 4) {

   213                     return false;

   214                 }

   215 

   216                 // Remove leading zeros (this is safe because of the above)

   217                 $ipv6_part = ltrim($ipv6_part, '0');

   218                 if ($ipv6_part === '') {

   219                     $ipv6_part = '0';

   220                 }

   221 

   222                 // Check the value is valid

   223                 $value = hexdec($ipv6_part);

   224                 if (dechex($value) !== strtolower($ipv6_part) || $value < 0 || $value > 0xFFFF) {

   225                     return false;

   226                 }

   227             }

   228             if (count($ipv4) === 4) {

   229                 foreach ($ipv4 as $ipv4_part) {

   230                     $value = (int) $ipv4_part;

   231                     if ((string) $value !== $ipv4_part || $value < 0 || $value > 0xFF) {

   232                         return false;

   233                     }

   234                 }

   235             }

   236             return true;

   237         }

   238 

   239         return false;

   240     }

   241 

   242     /**

   243      * Checks if the given IP is a valid IPv6 address

   244      *

   245      * @codeCoverageIgnore

   246      * @deprecated Use {@see IPv6::check_ipv6()} instead

   247      * @see check_ipv6

   248      * @param string $ip An IPv6 address

   249      * @return bool true if $ip is a valid IPv6 address

   250      */

   251     public static function checkIPv6($ip)

   252     {

   253         return self::check_ipv6($ip);

   254     }

   255 }

   256 

   257 class_alias('SimplePie\Net\IPv6', 'SimplePie_Net_IPv6');