1: <?php
 2: 
 3: namespace Genetsis\core;
 4: 
 5: /**
 6:  * This class is used to wrap encryption functions.
 7:  *
 8:  * @package   Genetsis
 9:  * @category  Helper
10:  * @version   1.0
11:  * @access    private
12:  */
13: class Encryption
14: {
15:     /** @var string The secret key to encrypt data. */
16:     private $_skey = "yourSecretKey";
17: 
18:     /**
19:      * @param string The secret key to encrypt data.
20:      */
21:     public function __construct($client_secret)
22:     {
23:         $this->_skey = str_pad(trim((string)$client_secret), 32, '\0');
24:     }
25: 
26:     /**
27:      * Encodes a string using a secret key.
28:      *
29:      * @param string The string to be encoded.
30:      * @return mixed The string encoded or FALSE.
31:      */
32:     public function encode($value)
33:     {
34:         if (!$value) {
35:             return false;
36:         }
37:         $iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
38:         $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
39:         $crypttext = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $this->_skey, $value, MCRYPT_MODE_ECB, $iv);
40:         return trim($this->safe_b64encode($crypttext));
41:     }
42: 
43:     /**
44:      * Encodes a string using base64.
45:      *
46:      * @param $string The string to be encoded.
47:      * @return mixed The encoded string.
48:      */
49:     public function safe_b64encode($string)
50:     {
51:         return str_replace(array('+', '/', '='), array('-', '_', ''), base64_encode($string));
52:     }
53: 
54:     /**
55:      * Decodes a string using a secret key.
56:      *
57:      * @param string The string to be decoded.
58:      * @return mixed The string decoded or FALSE.
59:      */
60:     public function decode($value)
61:     {
62:         if (!$value) {
63:             return false;
64:         }
65:         $iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
66:         $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
67:         $decrypttext = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $this->_skey, $this->safe_b64decode($value), MCRYPT_MODE_ECB, $iv);
68:         return trim($decrypttext);
69:     }
70: 
71:     /**
72:      * Decodes base64 encoded string.
73:      *
74:      * @param $string The string to be decoded.
75:      * @return The string decoded.
76:      */
77:     public function safe_b64decode($string)
78:     {
79:         $data = str_replace(array('-', '_'), array('+', '/'), $string);
80:         $mod4 = (strlen($data) % 4);
81:         if ($mod4) {
82:             $data .= substr('====', $mod4);
83:         }
84:         return base64_decode($data);
85:     }
86: }