<?php
/**
* CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
* Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
*
* Licensed under The MIT License
* For full copyright and license information, please see the LICENSE.txt
* Redistributions of files must retain the above copyright notice.
*
* @copyright Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
* @link https://cakephp.org CakePHP(tm) Project
* @since 3.0.0
* @license https://opensource.org/licenses/mit-license.php MIT License
*/
namespace Cake\Utility\Crypto;
use LogicException;
/**
* OpenSSL implementation of crypto features for Cake\Utility\Security
*
* OpenSSL should be favored over mcrypt as it is actively maintained and
* more widely available.
*
* This class is not intended to be used directly and should only
* be used in the context of Cake\Utility\Security.
*
* @internal
*/
class OpenSsl
{
/**
* @var string
*/
const METHOD_AES_256_CBC = 'aes-256-cbc';
/**
* Not implemented
*
* @param string $text Encrypted string to decrypt, normal string to encrypt
* @param string $key Key to use as the encryption key for encrypted data.
* @param string $operation Operation to perform, encrypt or decrypt
* @throws \LogicException Rijndael compatibility does not exist with Openssl.
* @return void
*/
public static function rijndael($text, $key, $operation)
{
throw new LogicException('rijndael is not compatible with OpenSSL. Use mcrypt instead.');
}
/**
* Encrypt a value using AES-256.
*
* *Caveat* You cannot properly encrypt/decrypt data with trailing null bytes.
* Any trailing null bytes will be removed on decryption due to how PHP pads messages
* with nulls prior to encryption.
*
* @param string $plain The value to encrypt.
* @param string $key The 256 bit/32 byte key to use as a cipher key.
* @return string Encrypted data.
* @throws \InvalidArgumentException On invalid data or key.
*/
public static function encrypt($plain, $key)
{
$method = static::METHOD_AES_256_CBC;
$ivSize = openssl_cipher_iv_length($method);
$iv = openssl_random_pseudo_bytes($ivSize);
return $iv . openssl_encrypt($plain, $method, $key, OPENSSL_RAW_DATA, $iv);
}
/**
* Decrypt a value using AES-256.
*
* @param string $cipher The ciphertext to decrypt.
* @param string $key The 256 bit/32 byte key to use as a cipher key.
* @return string Decrypted data. Any trailing null bytes will be removed.
* @throws \InvalidArgumentException On invalid data or key.
*/
public static function decrypt($cipher, $key)
{
$method = static::METHOD_AES_256_CBC;
$ivSize = openssl_cipher_iv_length($method);
$iv = mb_substr($cipher, 0, $ivSize, '8bit');
$cipher = mb_substr($cipher, $ivSize, null, '8bit');
return openssl_decrypt($cipher, $method, $key, OPENSSL_RAW_DATA, $iv);
}
}