A ifname counterpart for the "from" attribute

[Ondrej Zajicek]

On Fri, Mar 26, 2021 at 01:00:52PM +0100, Marcel Krüger wrote:
> Hi,
> 
> is there any way to identify in a filter the interface the route was
> learned from? So basically an attribute which relates to "from" like
> ifname and ifindex relate to "gw"? This would be particularly useful
> when "from" is a link lcal address and therefore might not be enough to
> identify the source.
> 
> If this doesn't exists, is there another way to enforce that the
> "gw" is always on the same interface the route was learned on whithout
> ..
> If not, would a patch implementing such an route attribute have a chance
> of being merged?


Hi

Iface associated with 'from' is not stored internally. Check like
'gw = from' work also for link local address, because link-local
next_hop is resolved only on the same iface, but that is more strict
check that you wanted.

We currently do not support iface as a value for regular attributes
('ifname' itself is an exception and only a temporary solution), but
we have some pending patches that redesign route attributes.

-- 
Elen sila lumenn' omentielvo

Ondrej 'Santiago' Zajicek (email: santiago at crfreenet.org)
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