/**
* XOR two-way encryption/decryption, with a base64 wrapper.
*
* @package optimizeMember\Utilities
* @since 3.5
*
* @param str $base64 A string of data to decrypt. Should still be base64 encoded.
* @param str $key Optional. Key used originally for encryption. Defaults to the one configured for optimizeMember. Short of that, defaults to: ``wp_salt()``.
* @return str Decrypted string.
*/
public static function xdecrypt($base64 = FALSE, $key = FALSE)
{
$base64 = is_string($base64) ? $base64 : "";
$e = strlen($base64) ? c_ws_plugin__optimizemember_utils_strings::base64_url_safe_decode($base64) : "";
/**/
if (strlen($e) && preg_match("/^~xe(?:\\:([a-zA-Z0-9]+))?\\|(.*?)\$/s", $e, $md5_e)) {
$key = c_ws_plugin__optimizemember_utils_encryption::key($key);
/**/
if (strlen($md5_e[2]) && (!$md5_e[1] || $md5_e[1] === md5($md5_e[2]))) {
/**/
for ($i = 1, $d = ""; $i <= strlen($md5_e[2]); $i++) {
$char = substr($md5_e[2], $i - 1, 1);
$keychar = substr($key, $i % strlen($key) - 1, 1);
$d .= chr(ord($char) - ord($keychar));
}
}
if (isset($d) && is_string($d) && strlen($d)) {
/**/
if (strlen($d = preg_replace("/^~xe\\|/", "", $d, 1, $xe)) && $xe) {
$d = $d;
} else {
/* Else we need to empty this out. */
$d = "";
}
}
/**/
return isset($d) && is_string($d) && strlen($d) ? $string = $d : "";
} else {
/* Otherwise we must fail here with an empty string value. */
return "";
}
}
