PHP: Encryption/Decryption

Coding      

This code works with a JSON stream encrypted with CryptoJS. You can use PHP with openSSL support to decrypt the data stream using your password.

Decrypt

/**
* Decrypt data from a CryptoJS json encoding string
*
* @param mixed $passphrase
* @param mixed $jsonString
* @return mixed
*/
function Decrypt($passphrase, $jsonString){
    $jsondata = json_decode($jsonString, true);
    $salt = hex2bin($jsondata["s"]);
    $ct = base64_decode($jsondata["ct"]);
    $iv  = hex2bin($jsondata["iv"]);
    $concatedPassphrase = $passphrase.$salt;
    $md5 = array();
    $md5[0] = md5($concatedPassphrase, true);
    $result = $md5[0];
    for ($i = 1; $i < 3; $i++) {
        $md5[$i] = md5($md5[$i - 1].$concatedPassphrase, true);
        $result .= $md5[$i];
    }
    $key = substr($result, 0, 32);
    $data = openssl_decrypt($ct, 'aes-256-cbc', $key, true, $iv);
    return json_decode($data, true);
}

Encrypt

/**
* Encrypt value to a cryptojs compatiable json encoding string
*
* @param mixed $passphrase
* @param mixed $value
* @return string
*/
function Encrypt($passphrase, $value){
    $salt = openssl_random_pseudo_bytes(8);
    $salted = '';
    $dx = '';
    while (strlen($salted) < 48) {
        $dx = md5($dx.$passphrase.$salt, true);
        $salted .= $dx;
    }
    $key = substr($salted, 0, 32);
    $iv  = substr($salted, 32,16);
    $encrypted_data = openssl_encrypt(json_encode($value), 'aes-256-cbc', $key, true, $iv);
    $data = array("ct" => base64_encode($encrypted_data), "iv" => bin2hex($iv), "s" => bin2hex($salt));
    return json_encode($data);

Execute

$json = file_get_contents('https://encryptedURL');
$data = json_decode($json);
$secret = "YOUR PASSWORD";
$rdat = Decrypt($secret, $json);
echo $rdat;

Example:

$encrypted = Encrypt("my passphrase", "value to encrypt");
$decrypted = Decrypt("my passphrase", $encrypted);