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   1  <?php
   2  /**
   3   * Part of the Joomla Framework Crypt Package
   4   *
   5   * @copyright  Copyright (C) 2005 - 2021 Open Source Matters, Inc. All rights reserved.
   6   * @license    GNU General Public License version 2 or later; see LICENSE
   7   */
   8  
   9  namespace Joomla\Crypt\Cipher;
  10  
  11  use Joomla\Crypt\CipherInterface;
  12  use Joomla\Crypt\Exception\DecryptionException;
  13  use Joomla\Crypt\Exception\EncryptionException;
  14  use Joomla\Crypt\Exception\InvalidKeyException;
  15  use Joomla\Crypt\Exception\InvalidKeyTypeException;
  16  use Joomla\Crypt\Key;
  17  
  18  /**
  19   * Joomla cipher for encryption, decryption and key generation via the openssl extension.
  20   *
  21   * @since  2.0.0
  22   */
  23  class OpenSSL implements CipherInterface
  24  {
  25      /**
  26       * Initialisation vector for key generator method.
  27       *
  28       * @var    string
  29       * @since  2.0.0
  30       */
  31      private $iv;
  32  
  33      /**
  34       * Method to use for encryption.
  35       *
  36       * @var    string
  37       * @since  2.0.0
  38       */
  39      private $method;
  40  
  41      /**
  42       * Instantiate the cipher.
  43       *
  44       * @param   string  $iv      The initialisation vector to use
  45       * @param   string  $method  The encryption method to use
  46       *
  47       * @since   2.0.0
  48       */
  49  	public function __construct(string $iv, string $method)
  50      {
  51          $this->iv     = $iv;
  52          $this->method = $method;
  53      }
  54  
  55      /**
  56       * Method to decrypt a data string.
  57       *
  58       * @param   string  $data  The encrypted string to decrypt.
  59       * @param   Key     $key   The key object to use for decryption.
  60       *
  61       * @return  string  The decrypted data string.
  62       *
  63       * @since   2.0.0
  64       * @throws  DecryptionException if the data cannot be decrypted
  65       * @throws  InvalidKeyTypeException if the key is not valid for the cipher
  66       */
  67  	public function decrypt($data, Key $key)
  68      {
  69          // Validate key.
  70          if ($key->getType() !== 'openssl')
  71          {
  72              throw new InvalidKeyTypeException('openssl', $key->getType());
  73          }
  74  
  75          $cleartext = openssl_decrypt($data, $this->method, $key->getPrivate(), true, $this->iv);
  76  
  77          if ($cleartext === false)
  78          {
  79              throw new DecryptionException('Failed to decrypt data');
  80          }
  81  
  82          return $cleartext;
  83      }
  84  
  85      /**
  86       * Method to encrypt a data string.
  87       *
  88       * @param   string  $data  The data string to encrypt.
  89       * @param   Key     $key   The key object to use for encryption.
  90       *
  91       * @return  string  The encrypted data string.
  92       *
  93       * @since   2.0.0
  94       * @throws  EncryptionException if the data cannot be encrypted
  95       * @throws  InvalidKeyTypeException if the key is not valid for the cipher
  96       */
  97  	public function encrypt($data, Key $key)
  98      {
  99          // Validate key.
 100          if ($key->getType() !== 'openssl')
 101          {
 102              throw new InvalidKeyTypeException('openssl', $key->getType());
 103          }
 104  
 105          $encrypted = openssl_encrypt($data, $this->method, $key->getPrivate(), true, $this->iv);
 106  
 107          if ($encrypted === false)
 108          {
 109              throw new EncryptionException('Unable to encrypt data');
 110          }
 111  
 112          return $encrypted;
 113      }
 114  
 115      /**
 116       * Method to generate a new encryption key object.
 117       *
 118       * @param   array  $options  Key generation options.
 119       *
 120       * @return  Key
 121       *
 122       * @since   2.0.0
 123       * @throws  InvalidKeyException if the key cannot be generated
 124       */
 125  	public function generateKey(array $options = [])
 126      {
 127          $passphrase = $options['passphrase'] ?? false;
 128  
 129          if ($passphrase === false)
 130          {
 131              throw new InvalidKeyException('Missing passphrase file');
 132          }
 133  
 134          return new Key('openssl', $passphrase, 'unused');
 135      }
 136  
 137      /**
 138       * Check if the cipher is supported in this environment.
 139       *
 140       * @return  boolean
 141       *
 142       * @since   2.0.0
 143       */
 144  	public static function isSupported(): bool
 145      {
 146          return \extension_loaded('openssl');
 147      }
 148  }