NAME
cangw - manual page for cangw 2023.03-1
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 Classical 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 Classical 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 in hex (0 .. F)
- <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 in hex (0 .. 40)
- <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) ^ (can_id >> 8 & 0xFF)
EXAMPLES
cangw -A -s can0 -d vcan3 -e -f 123:C00007FF -m SET:IL:333.4.1122334455667788