On Wed, Mar 20, 2024 at 12:19:02PM +0100, Claudio Jeker wrote:
> While working on capability enforcement I realized that
> parse_notification() had the handling of ERR_OPEN / ERR_OPEN_CAPA wrong.
> 
> RFC5492 is fairly clear about ERR_OPEN_CAPA (Unsupported Capability, 7):
>    As explained in the "Overview of Operations" section, the Unsupported
>    Capability NOTIFICATION is a way for a BGP speaker to complain that
>    its peer does not support a required capability without which the
>    peering cannot proceed.  It MUST NOT be used when a BGP speaker
>    receives a capability that it does not understand; such capabilities
>    MUST be ignored.
> 
> So the logic in parse_notification() is reversed since it tries to turn
> off the capability that the other side complains about. So remove all this
> humbug.
> 
> Now since we are already in there parse the notification exclusivly with
> the ibuf api. Clear the last_reason when setting last_rcvd_errcode and
> last_rcvd_suberr. Parse the last_reason before calling log_notification()
> do this with ibuf functions which simplifes the code a bit (since the full
> buffer is memset to 0 the string does not need to be terminated anymore).
> 
> In log_notification() add handling for last_reason and also for ERR_OPEN /
> ERR_OPEN_CAPA. For ERR_OPEN_CAPA only look at the first capa_code and
> report that. I see little reason to dig deeper there (also it seems that
> bird and zebra both violate the RFC and send no data with the
> notification).

I wasn't aware that zebra was still a thing. Does that include quagga?

ok tb