Restrict access to SocketCAN to a certain user group

I have a PC to which a robot is connected via CAN (using SocketCAN). I'd like to control who can send commands to the robot, ideally through a group (i.e. only users who are in the "use_robot" group have permission to send/receive anything via CAN). How can I achieve this? To my understanding, SocketCAN uses network interfaces so, probably somehow with iptables?