<?php
/**
* Part of the Joomla Framework Crypt Package
*
* @copyright Copyright (C) 2005 - 2021 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE
*/
namespace Joomla\Crypt\Cipher;
use Joomla\Crypt\CipherInterface;
use Joomla\Crypt\Exception\DecryptionException;
use Joomla\Crypt\Exception\EncryptionException;
use Joomla\Crypt\Exception\InvalidKeyException;
use Joomla\Crypt\Exception\InvalidKeyTypeException;
use Joomla\Crypt\Key;
/**
* Joomla cipher for encryption, decryption and key generation via the openssl extension.
*
* @since 2.0.0
*/
class OpenSSL implements CipherInterface
{
/**
* Initialisation vector for key generator method.
*
* @var string
* @since 2.0.0
*/
private $iv;
/**
* Method to use for encryption.
*
* @var string
* @since 2.0.0
*/
private $method;
/**
* Instantiate the cipher.
*
* @param string $iv The initialisation vector to use
* @param string $method The encryption method to use
*
* @since 2.0.0
*/
public function __construct(string $iv, string $method)
{
$this->iv = $iv;
$this->method = $method;
}
/**
* Method to decrypt a data string.
*
* @param string $data The encrypted string to decrypt.
* @param Key $key The key object to use for decryption.
*
* @return string The decrypted data string.
*
* @since 2.0.0
* @throws DecryptionException if the data cannot be decrypted
* @throws InvalidKeyTypeException if the key is not valid for the cipher
*/
public function decrypt($data, Key $key)
{
// Validate key.
if ($key->getType() !== 'openssl')
{
throw new InvalidKeyTypeException('openssl', $key->getType());
}
$cleartext = openssl_decrypt($data, $this->method, $key->getPrivate(), true, $this->iv);
if ($cleartext === false)
{
throw new DecryptionException('Failed to decrypt data');
}
return $cleartext;
}
/**
* Method to encrypt a data string.
*
* @param string $data The data string to encrypt.
* @param Key $key The key object to use for encryption.
*
* @return string The encrypted data string.
*
* @since 2.0.0
* @throws EncryptionException if the data cannot be encrypted
* @throws InvalidKeyTypeException if the key is not valid for the cipher
*/
public function encrypt($data, Key $key)
{
// Validate key.
if ($key->getType() !== 'openssl')
{
throw new InvalidKeyTypeException('openssl', $key->getType());
}
$encrypted = openssl_encrypt($data, $this->method, $key->getPrivate(), true, $this->iv);
if ($encrypted === false)
{
throw new EncryptionException('Unable to encrypt data');
}
return $encrypted;
}
/**
* Method to generate a new encryption key object.
*
* @param array $options Key generation options.
*
* @return Key
*
* @since 2.0.0
* @throws InvalidKeyException if the key cannot be generated
*/
public function generateKey(array $options = [])
{
$passphrase = $options['passphrase'] ?? false;
if ($passphrase === false)
{
throw new InvalidKeyException('Missing passphrase file');
}
return new Key('openssl', $passphrase, 'unused');
}
/**
* Check if the cipher is supported in this environment.
*
* @return boolean
*
* @since 2.0.0
*/
public static function isSupported(): bool
{
return \extension_loaded('openssl');
}
}