CRestServer::getApplicationSignature

public function getApplicationSignature()
{
	$signature = '';

	$arRes = BitrixRestAppTable::getByClientId($this->clientId);
	if(is_array($arRes) && $arRes['SHARED_KEY'] <> '')
	{
		$methodState = is_array($this->securityMethodState)
			? $this->securityMethodState
			: array('data' => $this->securityMethodState);

		$methodState['state'] = $this->securityClientState;

		$signature = $this->makeSignature($arRes['SHARED_KEY'], $methodState);
	}

	return $signature;
}