Function loop

usbkill/usbkill.py:316–353

(settings)

	return settings
	
def loop(settings):
	# Main loop that checks every 'sleep_time' seconds if computer should be killed.
	# Allows only whitelisted usb devices to connect!
	# Does not allow usb device that was present during program start to disconnect!
	start_devices = lsusb()
	acceptable_devices = start_devices + settings['whitelist']
	
	# Write to logs that loop is starting:
	msg = "[INFO] Started patrolling the USB ports every " + str(settings['sleep_time']) + " seconds..."
	log(settings, msg)
	print(msg)

	# Main loop
	while True:
		# List the current usb devices
		current_devices = lsusb()

		# Check that all current devices are in the set of acceptable devices
		#   and their cardinality is less than or equal to what is allowed 
		for device, count in current_devices.items():
			if device not in acceptable_devices:
				# A device with unknown usbid detected
				kill_computer(settings)
			if count > acceptable_devices[device]:
				# Count of a usbid is larger than what is acceptable (too many devices sharing usbid)
				kill_computer(settings)

		# Check that all start devices are still present in current devices
		#   and their cardinality still the same 
		for device, count in start_devices.items():
			if device not in current_devices:
				# A usbid has disappeared completely
				kill_computer(settings)
			if count > current_devices[device]:
				# Count of a usbid device is lower than at program start (not enough devices for given usbid)
				kill_computer(settings)
				
		sleep(settings['sleep_time'])

def startup_checks():
	# Splash