szymor/bulwa-cansim

A minimalistic CAN simulator implementing a virtual bus concept.

Bulwa CAN Simulator

description

BCS is a minimalistic CAN simulator that implements a virtual bus concept known from, among other tools, Vector CANoe. Each network node can be scripted in Lua. Configuration of the environment can be made via editing a JSON configuration file. The application uses SocketCAN so it should be compatible with a wide range of USB-CAN adapters.

The work is in progress.

custom LUA API

node_id - an integer denoting the index of a node running the script,

node_name - a string containing the name of a node running the script,

enable_node(node_name_string) - enables the node named node_name_string,

disable_node(node_name_string) - disables the node named node_name_string,

disable_node() - disable a node running the script,

set_timer(interval) - arms the timer of a node with a given time interval; if interval == 0, then the timer is disarmed,

emit(msg) - sends a message over CAN or CAN FD, the msg table describes the message to be sent:

• msg.type - "CAN" or "CANFD",
• msg.id - message identifier,
• msg.dlc - CAN only, data length code to be sent; certain controllers allow to send DLC different than the actual message length; if not provided, it is assumed from msg's length (#msg),
• msg.eff - boolean, Extended Frame Format flag,
• msg.rtr - boolean, Remote Transmission Request flag,
• msg.err - boolean, Error Message Frame,
• msg.brs - CAN FD only, boolean, Bit Rate Switch,
• msg.esi - CAN FD only, boolean, Error State Indicator.

callbacks

on_enable

on_disable

on_message(msg) - msg contains details of the received message, the format is the same as for emit(msg),

on_timer(interval) - returns non-zero value for a periodic timer, returns zero to stop a timer, returns nil (i.e. nothing) if a timer was previously set in the callback by set_timer.

credits

Code by szymor aka vamastah.

to do

• add iso-tp frame support as lua library
• add obd support to virtual ecu
• add fuzzers (canbus, iso-tp, uds), obd scanners, canbus monitor (to search for diagnostic ids or other information)
• add inter-node communication means, maybe ping and on_pong API?
• add xml parser (lxp?), could be useful for parsing odx and cdd
• encapsulate bulwa functionality in blw object
• improve timer resolution (interrupt poll when a signal comes)
• add json configuration entries for socket options
• add parameters of canbus (mode, bitrate, data bitrate) to json

development cheatsheet

enable virtual CAN module and configure VCAN device

sudo modprobe vcan
sudo ip link add dev vcan0 type vcan
sudo ip link set up vcan0

configure hardware CAN device

# CAN
sudo ip link set can0 type can bitrate 500000
# CAN FD
sudo ip link set can0 type can bitrate 500000 dbitrate 5000000 fd on

sudo ip link set up can0

generate random messages

# CAN
while [ true ]; do cansend vcan0 1FFFFFFF#`head -c 8 /dev/urandom | xxd -p`; sleep 1; done

# CAN FD
while [ true ]; do cansend vcan0 1FFFFFFF##0`head -c 16 /dev/urandom | xxd -p`; sleep 1; done

send ISO-TP frames

echo "2E F1 90 30 31 32 33 34 35 36 37 38 39" | isotpsend -s 18DA0BFA -d 18DAFA0B vcan0

receive ISO-TP frames

isotprecv -s 18DA0BFA -d 18DAFA0B vcan0

dump messages from CAN bus

candump vcan0