CANGW

NAME

cangw - manual page for cangw 2020.11.0-1

SYNOPSIS

cangw [options]

DESCRIPTION

cangw - manage PF_CAN netlink gateway.

Commands:

	-A		(add a new rule)
	-D		(delete a rule)
	-F		(flush / delete all rules)
	-L		(list all rules)

Mandatory:

-s <src_dev>

(source netdevice)

-d <dst_dev>

(destination netdevice)

OPTIONS

	-X		(this is a CAN FD rule)
	-t		(preserve src_dev rx timestamp)
	-e		(echo sent frames - recommended on vcanx)
	-i		(allow to route to incoming interface)

-u <uid>

(user defined modification identifier)

-l <hops>

(limit the number of frame hops / routings)

-f <filter>

(set CAN filter)

-m <mod>

(set Classic CAN frame modifications)

-M <MOD>

(set CAN FD frame modifications)

-x <from_idx>:<to_idx>:<result_idx>:<init_xor_val>

(XOR checksum)

-c <from>:<to>:<result>:<init_val>:<xor_val>:<crctab[256]>

(CRC8 cs)

-p <profile>:[<profile_data>]

(CRC8 checksum profile & parameters)

Values are given and expected in hexadecimal values. Leading 0s can be omitted.

<filter> is a <value><mask> CAN identifier filter:

<can_id>:<can_mask>

(matches when <received_can_id> & mask == can_id & mask)

<can_id>˜<can_mask>

(matches when <received_can_id> & mask != can_id & mask)

<mod> is a CAN frame modification instruction consisting of <instruction>:<can_frame-elements>:<can_id>.<can_dlc>.<can_data>
<instruction>

is one of ’AND’ ’OR’ ’XOR’ ’SET’

<can_frame-elements>

is _one_ or _more_ of ’I’dentifier ’L’ength ’D’ata

<can_id>

is an u32 value containing the CAN Identifier

<can_dlc>

is an u8 value containing the data length code (0 .. 8)

<can_data>

is always eight(!) u8 values containing the CAN frames data

<MOD> is a CAN FD frame modification instruction consisting of <instruction>:<canfd_frame-elements>:<can_id>.<flags>.<len>.<can_data>
<instruction>

is one of ’AND’ ’OR’ ’XOR’ ’SET’

<canfd_frame-elements>

is _one_ or _more_ of ’I’d ’F’lags ’L’ength ’D’ata

<can_id>

is an u32 value containing the CAN FD Identifier

<flags>

is an u8 value containing CAN FD flags (CANFD_BRS, CANFD_ESI)

<len>

is an u8 value containing the data length (0 .. 64)

<can_data>

is always 64(!) u8 values containing the CAN FD frames data

The max. four modifications are performed in the order AND -> OR -> XOR -> SET

Supported CRC 8 profiles:

Profile ’1’ (1U8)

add one additional u8 value

Profile ’2’ (16U8)

add u8 value from table[16] indexed by (data[1] & 0xF)

Profile ’3’ (SFFID_XOR)

add u8 value (can_id & 0xFF) ˆ (can_id >> 8 & 0xFF)

EXAMPLES

cangw -A -s can0 -d vcan3 -e -f 123:C00007FF -m SET:IL:333.4.1122334455667788