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  • Bug fixes for general core bugs in 4.0.x will end 8 May 2023 (12 months).
  • Bug fixes for security issues in 4.0.x will end 13 November 2023 (18 months).
  • PHP version: minimum PHP 7.3.0 Note: the minimum PHP version has increased since Moodle 3.10. PHP 7.4.x is also supported.
   1  <?php
   2  /**
   3   * Copyright 2014 TrueServer B.V.
   4   * Copyright 2015-2017 Horde LLC (http://www.horde.org/)
   5   *
   6   * See the enclosed file LICENSE for license information (BSD). If you
   7   * did not receive this file, see http://www.horde.org/licenses/bsd.
   8   *
   9   * @author   Renan Gonçalves <renan.saddam@gmail.com>
  10   * @author   Michael Slusarz <slusarz@horde.org>
  11   * @category Horde
  12   * @license  http://www.horde.org/licenses/bsd BSD
  13   * @package  Idna
  14   */
  15  
  16  /**
  17   * Punycode implementation as described in RFC 3492.
  18   *
  19   * Original code (v1.0.1; released under the MIT License):
  20   *     https://github.com/true/php-punycode/
  21   *
  22   * @author    Renan Gonçalves <renan.saddam@gmail.com>
  23   * @author    Michael Slusarz <slusarz@horde.org>
  24   * @category  Horde
  25   * @copyright 2014 TrueServer B.V.
  26   * @copyright 2015-2017 Horde LLC
  27   * @license   http://www.horde.org/licenses/bsd BSD
  28   * @package   Idna
  29   * @link      http://tools.ietf.org/html/rfc3492
  30   */
  31  class Horde_Idna_Punycode
  32  {
  33      /**
  34       * Bootstring parameter values.
  35       */
  36      const BASE         = 36;
  37      const TMIN         = 1;
  38      const TMAX         = 26;
  39      const SKEW         = 38;
  40      const DAMP         = 700;
  41      const INITIAL_BIAS = 72;
  42      const INITIAL_N    = 128;
  43      const PREFIX       = 'xn--';
  44      const DELIMITER    = '-';
  45  
  46      /**
  47       * Encode table.
  48       *
  49       * @param array
  50       */
  51      protected static $_encodeTable = array(
  52          'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l',
  53          'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x',
  54          'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
  55      );
  56  
  57      /**
  58       * Decode table.
  59       *
  60       * @param array
  61       */
  62      protected static $_decodeTable = array(
  63          'a' =>  0, 'b' =>  1, 'c' =>  2, 'd' =>  3, 'e' =>  4, 'f' =>  5,
  64          'g' =>  6, 'h' =>  7, 'i' =>  8, 'j' =>  9, 'k' => 10, 'l' => 11,
  65          'm' => 12, 'n' => 13, 'o' => 14, 'p' => 15, 'q' => 16, 'r' => 17,
  66          's' => 18, 't' => 19, 'u' => 20, 'v' => 21, 'w' => 22, 'x' => 23,
  67          'y' => 24, 'z' => 25, '0' => 26, '1' => 27, '2' => 28, '3' => 29,
  68          '4' => 30, '5' => 31, '6' => 32, '7' => 33, '8' => 34, '9' => 35
  69      );
  70  
  71      /**
  72       * Encode a domain to its Punycode version.
  73       *
  74       * @param string $input  Domain name in Unicde to be encoded.
  75       *
  76       * @return string  Punycode representation in ASCII.
  77       */
  78      public function encode($input)
  79      {
  80          $parts = explode('.', $input);
  81  
  82          foreach ($parts as &$part) {
  83              $part = $this->_encodePart($part);
  84          }
  85  
  86          return implode('.', $parts);
  87      }
  88  
  89      /**
  90       * Encode a part of a domain name, such as tld, to its Punycode version.
  91       *
  92       * @param string $input  Part of a domain name.
  93       *
  94       * @return string  Punycode representation of a domain part.
  95       */
  96      protected function _encodePart($input)
  97      {
  98          $codePoints = $this->_codePoints($input);
  99  
 100          $n = static::INITIAL_N;
 101          $bias = static::INITIAL_BIAS;
 102          $delta = 0;
 103          $h = $b = count($codePoints['basic']);
 104  
 105          $output = '';
 106          foreach ($codePoints['basic'] as $code) {
 107              $output .= $this->_codePointToChar($code);
 108          }
 109          if ($input === $output) {
 110              return $output;
 111          }
 112          if ($b > 0) {
 113              $output .= static::DELIMITER;
 114          }
 115  
 116          $codePoints['nonBasic'] = array_unique($codePoints['nonBasic']);
 117          sort($codePoints['nonBasic']);
 118  
 119          $i = 0;
 120          $length = Horde_String::length($input, 'UTF-8');
 121  
 122          while ($h < $length) {
 123              $m = $codePoints['nonBasic'][$i++];
 124              $delta = $delta + ($m - $n) * ($h + 1);
 125              $n = $m;
 126  
 127              foreach ($codePoints['all'] as $c) {
 128                  if (($c < $n) || ($c < static::INITIAL_N)) {
 129                      ++$delta;
 130                  }
 131  
 132                  if ($c === $n) {
 133                      $q = $delta;
 134                      for ($k = static::BASE; ; $k += static::BASE) {
 135                          $t = $this->_calculateThreshold($k, $bias);
 136                          if ($q < $t) {
 137                              break;
 138                          }
 139  
 140                          $code = $t + (($q - $t) % (static::BASE - $t));
 141                          $output .= static::$_encodeTable[$code];
 142  
 143                          $q = ($q - $t) / (static::BASE - $t);
 144                      }
 145  
 146                      $output .= static::$_encodeTable[$q];
 147                      $bias = $this->_adapt($delta, $h + 1, ($h === $b));
 148                      $delta = 0;
 149                      ++$h;
 150                  }
 151              }
 152  
 153              ++$delta;
 154              ++$n;
 155          }
 156  
 157          return static::PREFIX . $output;
 158      }
 159  
 160      /**
 161       * Decode a Punycode domain name to its Unicode counterpart.
 162       *
 163       * @param string $input  Domain name in Punycode
 164       *
 165       * @return string  Unicode domain name.
 166       */
 167      public function decode($input)
 168      {
 169          $parts = explode('.', $input);
 170  
 171          foreach ($parts as &$part) {
 172              if (strpos($part, static::PREFIX) === 0) {
 173                  $part = $this->_decodePart(
 174                      substr($part, strlen(static::PREFIX))
 175                  );
 176              }
 177          }
 178  
 179          return implode('.', $parts);
 180      }
 181  
 182      /**
 183       * Decode a part of domain name, such as tld.
 184       *
 185       * @param string $input  Part of a domain name.
 186       *
 187       * @return string  Unicode domain part.
 188       */
 189      protected function _decodePart($input)
 190      {
 191          $n = static::INITIAL_N;
 192          $i = 0;
 193          $bias = static::INITIAL_BIAS;
 194          $output = '';
 195  
 196          $pos = strrpos($input, static::DELIMITER);
 197          if ($pos !== false) {
 198              $output = substr($input, 0, $pos++);
 199          } else {
 200              $pos = 0;
 201          }
 202  
 203          $outputLength = strlen($output);
 204          $inputLength = strlen($input);
 205  
 206          /* Punycode lookup is case-insensitive. */
 207          $input = Horde_String::lower($input);
 208  
 209          while ($pos < $inputLength) {
 210              $oldi = $i;
 211              $w = 1;
 212  
 213              for ($k = static::BASE; ; $k += static::BASE) {
 214                  $digit = static::$_decodeTable[$input[$pos++]];
 215                  $i = $i + ($digit * $w);
 216                  $t = $this->_calculateThreshold($k, $bias);
 217  
 218                  if ($digit < $t) {
 219                      break;
 220                  }
 221  
 222                  $w = $w * (static::BASE - $t);
 223              }
 224  
 225              $bias = $this->_adapt($i - $oldi, ++$outputLength, ($oldi === 0));
 226              $n = $n + (int) ($i / $outputLength);
 227              $i = $i % ($outputLength);
 228  
 229              $output = Horde_String::substr($output, 0, $i, 'UTF-8') .
 230                  $this->_codePointToChar($n) .
 231                  Horde_String::substr($output, $i, $outputLength - 1, 'UTF-8');
 232  
 233              ++$i;
 234          }
 235  
 236          return $output;
 237      }
 238  
 239      /**
 240       * Calculate the bias threshold to fall between TMIN and TMAX.
 241       *
 242       * @param integer $k
 243       * @param integer $bias
 244       *
 245       * @return integer
 246       */
 247      protected function _calculateThreshold($k, $bias)
 248      {
 249          if ($k <= ($bias + static::TMIN)) {
 250              return static::TMIN;
 251          } elseif ($k >= ($bias + static::TMAX)) {
 252              return static::TMAX;
 253          }
 254          return $k - $bias;
 255      }
 256  
 257      /**
 258       * Bias adaptation.
 259       *
 260       * @param integer $delta
 261       * @param integer $numPoints
 262       * @param boolean $firstTime
 263       *
 264       * @return integer
 265       */
 266      protected function _adapt($delta, $numPoints, $firstTime)
 267      {
 268          $delta = (int) (
 269              ($firstTime)
 270                  ? $delta / static::DAMP
 271                  : $delta / 2
 272              );
 273          $delta += (int) ($delta / $numPoints);
 274  
 275          $k = 0;
 276          while ($delta > ((static::BASE - static::TMIN) * static::TMAX) / 2) {
 277              $delta = (int) ($delta / (static::BASE - static::TMIN));
 278              $k = $k + static::BASE;
 279          }
 280          $k = $k + (int) (((static::BASE - static::TMIN + 1) * $delta) / ($delta + static::SKEW));
 281  
 282          return $k;
 283      }
 284  
 285      /**
 286       * List code points for a given input.
 287       *
 288       * @param string $input
 289       *
 290       * @return array  Multi-dimension array with basic, non-basic and
 291       *                aggregated code points.
 292       */
 293      protected function _codePoints($input)
 294      {
 295          $codePoints = array(
 296              'all'      => array(),
 297              'basic'    => array(),
 298              'nonBasic' => array()
 299          );
 300  
 301          $len = Horde_String::length($input, 'UTF-8');
 302          for ($i = 0; $i < $len; ++$i) {
 303              $char = Horde_String::substr($input, $i, 1, 'UTF-8');
 304              $code = $this->_charToCodePoint($char);
 305              if ($code < 128) {
 306                  $codePoints['all'][] = $codePoints['basic'][] = $code;
 307              } else {
 308                  $codePoints['all'][] = $codePoints['nonBasic'][] = $code;
 309              }
 310          }
 311  
 312          return $codePoints;
 313      }
 314  
 315      /**
 316       * Convert a single or multi-byte character to its code point.
 317       *
 318       * @param string $char
 319       *
 320       * @return integer
 321       */
 322      protected function _charToCodePoint($char)
 323      {
 324          $code = ord($char[0]);
 325          if ($code < 128) {
 326              return $code;
 327          } elseif ($code < 224) {
 328              return (($code - 192) * 64) + (ord($char[1]) - 128);
 329          } elseif ($code < 240) {
 330              return (($code - 224) * 4096) + ((ord($char[1]) - 128) * 64) + (ord($char[2]) - 128);
 331          }
 332          return (($code - 240) * 262144) + ((ord($char[1]) - 128) * 4096) + ((ord($char[2]) - 128) * 64) + (ord($char[3]) - 128);
 333      }
 334  
 335      /**
 336       * Convert a code point to its single or multi-byte character
 337       *
 338       * @param integer $code
 339       *
 340       * @return string
 341       */
 342      protected function _codePointToChar($code)
 343      {
 344          if ($code <= 0x7F) {
 345              return chr($code);
 346          } elseif ($code <= 0x7FF) {
 347              return chr(($code >> 6) + 192) . chr(($code & 63) + 128);
 348          } elseif ($code <= 0xFFFF) {
 349              return chr(($code >> 12) + 224) . chr((($code >> 6) & 63) + 128) . chr(($code & 63) + 128);
 350          }
 351          return chr(($code >> 18) + 240) . chr((($code >> 12) & 63) + 128) . chr((($code >> 6) & 63) + 128) . chr(($code & 63) + 128);
 352      }
 353  
 354  }