src/applications/files/format/PhabricatorFileROT13StorageFormat.php

   1 <?php
   2
   3 /**
   4  * Trivial example of a file storage format for at-rest encryption.
   5  *
   6  * This format applies ROT13 encoding to file data as it is stored and
   7  * reverses it on the way out. This encoding is trivially reversible. This
   8  * format is for testing, developing, and understanding encoding formats and
   9  * is not intended for production use.
  10  */
  11 final class PhabricatorFileROT13StorageFormat
  12   extends PhabricatorFileStorageFormat {
  13
  14   const FORMATKEY = 'rot13';
  15
  16   public function getStorageFormatName() {
  17     return pht('Encoded (ROT13)');
  18   }
  19
  20   public function newReadIterator($raw_iterator) {
  21     $file = $this->getFile();
  22     $iterations = $file->getStorageProperty('iterations', 1);
  23
  24     $value = $file->loadDataFromIterator($raw_iterator);
  25     for ($ii = 0; $ii < $iterations; $ii++) {
  26       $value = str_rot13($value);
  27     }
  28
  29     return array($value);
  30   }
  31
  32   public function newWriteIterator($raw_iterator) {
  33     return $this->newReadIterator($raw_iterator);
  34   }
  35
  36   public function newStorageProperties() {
  37     // For extreme security, repeatedly encode the data using a random (odd)
  38     // number of iterations.
  39     return array(
  40       'iterations' => (mt_rand(1, 3) * 2) - 1,
  41     );
  42   }
  43
  44 }