ParagonIE_Sodium_Core32_XChaCha20::ietfStreamXorIc( string $message, string $nonce = '', string $key = '', string $ic = '' ): string

76    public static function ietfStreamXorIc($message, $nonce = '', $key = '', $ic = '')77    {78        return self::encryptBytes(79            new ParagonIE_Sodium_Core32_ChaCha20_IetfCtx(80                self::hChaCha20(self::substr($nonce, 0, 16), $key),81                "\x00\x00\x00\x00" . self::substr($nonce, 16, 8),82                $ic83            ),84            $message85        );86    }