Re: [PATCH nft 1/2] src: add dscp support

[Patrick McHardy <kaber@trash.net>]

On 26.11, Jan Engelhardt wrote:
> 
> On Wednesday 2015-11-25 21:01, Patrick McHardy wrote:
> >On 25.11, Pablo Neira Ayuso wrote:
> >>  #define TYPE_MAX		(__TYPE_MAX - 1)
> >> diff --git a/include/proto.h b/include/proto.h
> >> index a43bf98..41af0c1 100644
> >> --- a/include/proto.h
> >> +++ b/include/proto.h
> >> @@ -176,7 +176,7 @@ enum ip_hdr_fields {
> >>  	IPHDR_INVALID,
> >>  	IPHDR_VERSION,
> >>  	IPHDR_HDRLENGTH,
> >> -	IPHDR_TOS,
> >> +	IPHDR_DSCP,
> >
> >Shouldn't we keep both?
> 
> >From what I read from RFC 2474, DSCP is the 6-bit portion.
> The 8-bit field is known as
>   (a) TOS per IPv4 RFC
>   (b) TC (Traffic Class) per IPv6 RFC 2460
>   (c) DS per RFC 2472
> 
> I would therefore recommend against IPHDR_DSCP, and instead go
> with either of IPHDR_TOS, IPHDR_DS, IPHDR_DIFFSERV, or even
> some mnemonic involving traffic class.

But we actually do refer to the 6 bit sub-field and the further 2 bit ECN
sub-field, they are seperate fields with Pablo's patch.