On Sat. 19 Aug. 2023, 01:19, Jakub Kicinski <kuba@xxxxxxxxxx> wrote: > > On Thu, 17 Aug 2023 12:10:13 +0200 Martin Hundebøll wrote: > > + int len = nla_len(data[IFLA_CAN_HW_FILTER]); > > + int num_filter = len / sizeof(struct can_filter); > > + struct can_filter *filter = nla_data(data[IFLA_CAN_HW_FILTER]); > > This will prevent you from ever extending struct can_filter in > a backward-compatible fashion, right? I obviously know very little > about CAN but are you confident a more bespoke API to manipulate > filters individually and allow extensibility is not warranted? I follow Jakub's point of view. The current struct can_filter is not sound. Some devices such as the ES582.1 supports filtering of the CAN frame based on the flags (i.e. SFF/EFF, RTR, FDF). I think that each of the fields of the filter should have its own NLA declaration with the whole thing wrapped within a NLA_NESTED_ARRAY. I also think that there should then be a method to report the precise filtering capabilities of the hardware. Yours sincerely, Vincent Mailhol
