NoProtocol\Encryption\MySQL\AES\Crypter

Complexity

Total Complexity

6

Size/Duplication

Total Lines	82
Duplicated Lines	0 %

Test Coverage

Coverage

96.43%

Importance

Changes	3
Bugs	1	Features	0

4 Methods

Rating	Name	Duplication	Size	Complexity
A	decrypt()	0	10	1
A	generateKey()	0	8	2
A	encrypt()	0	15	2
A	__construct()	0	4	1

<?php
/**
 * Encrypt/decrypt data to a format compatible with MySQL aes_encrypt() & aes_decrypt() functions.
 *
 * @author    Bob Fanger <bob.fanger@noprotocol.nl>
 * @author    Anne Jan Brouwer <anne.jan.brouwer@noprotocol.nl>
 * @author    Govert Verschuur <govert.verschuur@noprotocol.nl>
 * @author    Renan Martins Pimentel <renan.pimentel@gmail.com>
 * @copyright 2016 NoProtocol
 * @license   https://opensource.org/licenses/MIT The MIT License (MIT)
 *
 * @version   2.0.1
 *
 * @link      http://www.smashingmagazine.com/2012/05/replicating-mysql-aes-encryption-methods-with-php/
 */

namespace NoProtocol\Encryption\MySQL\AES;

class Crypter
{
    protected $method;
    protected $key;

    /**
     * Crypter constructor.
     *
     * @param $seed
     * @param string $method default AES-128-ECB
     */
    public function __construct($seed, $method = 'AES-128-ECB')
    {
        $this->method = $method;
        $this->key = $this->generateKey($seed);
    }

    /**
     * Encrypts the data.
     *
     * @since  2.0
     *
     * @param string $data A string of data to encrypt.
     *
     * @return string (binary) The encrypted data
     */
    public function encrypt($data)
    {
        $chiperIvLength = openssl_cipher_iv_length($this->method);
        $iv = '';
        if ($chiperIvLength > 0) {
            $iv = openssl_random_pseudo_bytes($chiperIvLength);
        }
        $padValue = 16 - (strlen($data) % 16);

        return openssl_encrypt(
            str_pad($data, intval(16 * (floor(strlen($data) / 16) + 1)), chr($padValue)),
            $this->method,
            $this->key,
            OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING,
            $iv
        );
    }

    /**
     * Decrypts the data.
     *
     * @since  2.0
     *
     * @param string $data A (binary) string of encrypted data
     *
     * @return string Decrypted data
     */
    public function decrypt($data)
    {
        $data = openssl_decrypt(
            $data,
            $this->method,
            $this->key,
            OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING
        );

        return rtrim($data, "\x00..\x10");
    }

    /**
     * Create and set the key used for encryption.
     *
     * @since  2.0
     *
     * @param string $seed The seed used to create the key.
     *
     * @return string (binary) the key to use in the encryption process.
     */
    protected function generateKey($seed)
    {
        $key = str_repeat(chr(0), 16);
        for ($i = 0, $len = strlen($seed); $i < $len; $i++) {
            $key[$i % 16] = $key[$i % 16] ^ $seed[$i];
        }

        return $key;
    }
}