[Summary view] [Print] [Text view]

   1  <?php
   2  
   3  /**
   4   * Joomla! Content Management System
   5   *
   6   * @copyright  (C) 2017 Open Source Matters, Inc. <https://www.joomla.org>
   7   * @license    GNU General Public License version 2 or later; see LICENSE.txt
   8   */
   9  
  10  namespace Joomla\CMS\Crypt\Cipher;
  11  
  12  use Joomla\Crypt\CipherInterface;
  13  use Joomla\Crypt\Key;
  14  use ParagonIE\Sodium\Compat;
  15  
  16  // phpcs:disable PSR1.Files.SideEffects
  17  \defined('JPATH_PLATFORM') or die;
  18  // phpcs:enable PSR1.Files.SideEffects
  19  
  20  /**
  21   * JCrypt cipher for sodium algorithm encryption, decryption and key generation.
  22   *
  23   * @since  3.8.0
  24   */
  25  class SodiumCipher implements CipherInterface
  26  {
  27      /**
  28       * The message nonce to be used with encryption/decryption
  29       *
  30       * @var    string
  31       * @since  3.8.0
  32       */
  33      private $nonce;
  34  
  35      /**
  36       * Method to decrypt a data string.
  37       *
  38       * @param   string  $data  The encrypted string to decrypt.
  39       * @param   Key     $key   The key object to use for decryption.
  40       *
  41       * @return  string  The decrypted data string.
  42       *
  43       * @since   3.8.0
  44       * @throws  \RuntimeException
  45       */
  46      public function decrypt($data, Key $key)
  47      {
  48          // Validate key.
  49          if ($key->getType() !== 'sodium') {
  50              throw new \InvalidArgumentException('Invalid key of type: ' . $key->getType() . '.  Expected sodium.');
  51          }
  52  
  53          if (!$this->nonce) {
  54              throw new \RuntimeException('Missing nonce to decrypt data');
  55          }
  56  
  57          $decrypted = Compat::crypto_box_open(
  58              $data,
  59              $this->nonce,
  60              Compat::crypto_box_keypair_from_secretkey_and_publickey($key->getPrivate(), $key->getPublic())
  61          );
  62  
  63          if ($decrypted === false) {
  64              throw new \RuntimeException('Malformed message or invalid MAC');
  65          }
  66  
  67          return $decrypted;
  68      }
  69  
  70      /**
  71       * Method to encrypt a data string.
  72       *
  73       * @param   string  $data  The data string to encrypt.
  74       * @param   Key     $key   The key object to use for encryption.
  75       *
  76       * @return  string  The encrypted data string.
  77       *
  78       * @since   3.8.0
  79       * @throws  \RuntimeException
  80       */
  81      public function encrypt($data, Key $key)
  82      {
  83          // Validate key.
  84          if ($key->getType() !== 'sodium') {
  85              throw new \InvalidArgumentException('Invalid key of type: ' . $key->getType() . '.  Expected sodium.');
  86          }
  87  
  88          if (!$this->nonce) {
  89              throw new \RuntimeException('Missing nonce to decrypt data');
  90          }
  91  
  92          return Compat::crypto_box(
  93              $data,
  94              $this->nonce,
  95              Compat::crypto_box_keypair_from_secretkey_and_publickey($key->getPrivate(), $key->getPublic())
  96          );
  97      }
  98  
  99      /**
 100       * Method to generate a new encryption key object.
 101       *
 102       * @param   array  $options  Key generation options.
 103       *
 104       * @return  Key
 105       *
 106       * @since   3.8.0
 107       * @throws  \RuntimeException
 108       */
 109      public function generateKey(array $options = array())
 110      {
 111          // Generate the encryption key.
 112          $pair = Compat::crypto_box_keypair();
 113  
 114          return new Key('sodium', Compat::crypto_box_secretkey($pair), Compat::crypto_box_publickey($pair));
 115      }
 116  
 117      /**
 118       * Check if the cipher is supported in this environment.
 119       *
 120       * @return  boolean
 121       *
 122       * @since   4.0.0
 123       */
 124      public static function isSupported(): bool
 125      {
 126          return class_exists(Compat::class);
 127      }
 128  
 129      /**
 130       * Set the nonce to use for encrypting/decrypting messages
 131       *
 132       * @param   string  $nonce  The message nonce
 133       *
 134       * @return  void
 135       *
 136       * @since   3.8.0
 137       */
 138      public function setNonce($nonce)
 139      {
 140          $this->nonce = $nonce;
 141      }
 142  }