No experience with SocketCAN, but hopefully a good guess: SocketCAN is basically a socket (see Wikipedia article), but with a new protocol family, CAN. Perl can work fine with sockets, you "just" need to find a way to create a CAN socket instead of an IPv4, IPv6, or Unix domain socket. The Wikipedia article contains a very stripped down example in C that sets up a CAN socket. A little bit of messing with pack and unpack should be sufficient to call socket with the parameters required for a CAN socket. Reading from and writing to CAN devices requires another round of pack and unpack. Required constants and structures should be in linux/can.h and linux/can/raw.h.

Alexander