Re: [iproute2-next] tc flower: use right ethertype in icmp/arp parsing

[David Ahern <dsahern@gmail.com>]

On 10/19/20 5:47 AM, Zahari Doychev wrote:
> Currently the icmp and arp prsing functions are called with inccorect
> ethtype in case of vlan or cvlan filter options. In this case either
> cvlan_ethtype or vlan_ethtype has to be used.
> 
> Signed-off-by: Zahari Doychev <zahari.doychev@linux.com>
> ---
>  tc/f_flower.c | 43 ++++++++++++++++++++++++++-----------------
>  1 file changed, 26 insertions(+), 17 deletions(-)
> 
> diff --git a/tc/f_flower.c b/tc/f_flower.c
> index 00c919fd..dd9f3446 100644
> --- a/tc/f_flower.c
> +++ b/tc/f_flower.c
> @@ -1712,7 +1712,10 @@ static int flower_parse_opt(struct filter_util *qu, char *handle,
>  			}
>  		} else if (matches(*argv, "type") == 0) {
>  			NEXT_ARG();
> -			ret = flower_parse_icmp(*argv, eth_type, ip_proto,
> +			ret = flower_parse_icmp(*argv, cvlan_ethtype ?
> +						cvlan_ethtype : vlan_ethtype ?
> +						vlan_ethtype : eth_type,
> +						ip_proto,

looks correct to me, but would like confirmation of the intent from Simon.

Also, I am not a fan of the readability of that coding style. Rather
than repeat that expression multiple times, make a short helper to
return the relevant eth type and use a temp variable for it. You should
also comment that relevant eth type changes as arguments are parsed.

Thanks,