/**
* Generate key by time
*
* @access private
* @param string $seed
* @param integer|string $delta strtotime
* @return string
*/
private function generateByTime($seed, $delta)
{
$end = strtotime($delta);
$hash = hash_hmac("sha256", $seed, $this->signing_key, TRUE);
$iters = 0;
while (time() < $end) {
$hash = hash_hmac("sha256", $hash, $this->signing_key, TRUE);
$iters += 1;
}
$this->iterations = $iters;
return Fernet::base64url_encode($hash);
}
/**
* Gets the site-specific encryption and signing key.
*
* If the key does not exist, it is automatically generated.
*
* @return string the site-specific encryption and signing key
* as a base64url encoded string
*/
protected static function getKey()
{
$store = StoreManager::instance();
$key = $store->getSetting('oauth-fernet');
if ($key == NULL) {
$rand = new Random();
$key = Fernet::base64url_encode($rand->bytes(32));
$store->setSetting('oauth-fernet', $key);
}
return $key;
}
/**
* Gets the site-specific encryption and signing key.
*
* If the key does not exist, it is automatically generated.
*
* @return string the site-specific encryption and signing key
* as a base64url encoded string
*/
private static function getSiteToken()
{
$store = StoreManager::instance();
$site_token = $store->getSetting('site-token');
if ($site_token == NULL) {
$rand = new Random();
$site_token = Fernet::base64url_encode($rand->bytes(32));
$store->setSetting('site-token', $site_token);
}
return $site_token;
}
