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Differences Between: [Versions 310 and 311] [Versions 311 and 400] [Versions 311 and 401] [Versions 311 and 402] [Versions 311 and 403] [Versions 39 and 311]

   1  <?php
   2  
   3  namespace PhpOffice\PhpSpreadsheet\Shared;
   4  
   5  use PhpOffice\PhpSpreadsheet\Exception;
   6  use PhpOffice\PhpSpreadsheet\Worksheet\Protection;
   7  
   8  class PasswordHasher
   9  {
  10      /**
  11       * Get algorithm name for PHP.
  12       */
  13      private static function getAlgorithm(string $algorithmName): string
  14      {
  15          if (!$algorithmName) {
  16              return '';
  17          }
  18  
  19          // Mapping between algorithm name in Excel and algorithm name in PHP
  20          $mapping = [
  21              Protection::ALGORITHM_MD2 => 'md2',
  22              Protection::ALGORITHM_MD4 => 'md4',
  23              Protection::ALGORITHM_MD5 => 'md5',
  24              Protection::ALGORITHM_SHA_1 => 'sha1',
  25              Protection::ALGORITHM_SHA_256 => 'sha256',
  26              Protection::ALGORITHM_SHA_384 => 'sha384',
  27              Protection::ALGORITHM_SHA_512 => 'sha512',
  28              Protection::ALGORITHM_RIPEMD_128 => 'ripemd128',
  29              Protection::ALGORITHM_RIPEMD_160 => 'ripemd160',
  30              Protection::ALGORITHM_WHIRLPOOL => 'whirlpool',
  31          ];
  32  
  33          if (array_key_exists($algorithmName, $mapping)) {
  34              return $mapping[$algorithmName];
  35          }
  36  
  37          throw new Exception('Unsupported password algorithm: ' . $algorithmName);
  38      }
  39  
  40      /**
  41       * Create a password hash from a given string.
  42       *
  43       * This method is based on the algorithm provided by
  44       * Daniel Rentz of OpenOffice and the PEAR package
  45       * Spreadsheet_Excel_Writer by Xavier Noguer <xnoguer@rezebra.com>.
  46       *
  47       * @param string $pPassword Password to hash
  48       */
  49      private static function defaultHashPassword(string $pPassword): string
  50      {
  51          $password = 0x0000;
  52          $charPos = 1; // char position
  53  
  54          // split the plain text password in its component characters
  55          $chars = preg_split('//', $pPassword, -1, PREG_SPLIT_NO_EMPTY);
  56          foreach ($chars as $char) {
  57              $value = ord($char) << $charPos++; // shifted ASCII value
  58              $rotated_bits = $value >> 15; // rotated bits beyond bit 15
  59              $value &= 0x7fff; // first 15 bits
  60              $password ^= ($value | $rotated_bits);
  61          }
  62  
  63          $password ^= strlen($pPassword);
  64          $password ^= 0xCE4B;
  65  
  66          return strtoupper(dechex($password));
  67      }
  68  
  69      /**
  70       * Create a password hash from a given string by a specific algorithm.
  71       *
  72       * 2.4.2.4 ISO Write Protection Method
  73       *
  74       * @see https://docs.microsoft.com/en-us/openspecs/office_file_formats/ms-offcrypto/1357ea58-646e-4483-92ef-95d718079d6f
  75       *
  76       * @param string $password Password to hash
  77       * @param string $algorithm Hash algorithm used to compute the password hash value
  78       * @param string $salt Pseudorandom string
  79       * @param int $spinCount Number of times to iterate on a hash of a password
  80       *
  81       * @return string Hashed password
  82       */
  83      public static function hashPassword(string $password, string $algorithm = '', string $salt = '', int $spinCount = 10000): string
  84      {
  85          $phpAlgorithm = self::getAlgorithm($algorithm);
  86          if (!$phpAlgorithm) {
  87              return self::defaultHashPassword($password);
  88          }
  89  
  90          $saltValue = base64_decode($salt);
  91          $encodedPassword = mb_convert_encoding($password, 'UCS-2LE', 'UTF-8');
  92  
  93          $hashValue = hash($phpAlgorithm, $saltValue . $encodedPassword, true);
  94          for ($i = 0; $i < $spinCount; ++$i) {
  95              $hashValue = hash($phpAlgorithm, $hashValue . pack('L', $i), true);
  96          }
  97  
  98          return base64_encode($hashValue);
  99      }
 100  }