Le 26/08/2022 à 13:46, Eyal Birger a écrit : > XFRM interfaces provide the association of various XFRM transformations > to a netdevice using an 'if_id' identifier common to both the XFRM data > structures (polcies, states) and the interface. The if_id is configured by > the controlling entity (usually the IKE daemon) and can be used by the > administrator to define logical relations between different connections. > > For example, different connections can share the if_id identifier so > that they pass through the same interface, . However, currently it is > not possible for connections using a different if_id to use the same > interface while retaining the logical separation between them, without > using additional criteria such as skb marks or different traffic > selectors. > > When having a large number of connections, it is useful to have a the > logical separation offered by the if_id identifier but use a single > network interface. Similar to the way collect_md mode is used in IP > tunnels. > > This patch attempts to enable different configuration mechanisms - such > as ebpf programs, LWT encapsulations, and TC - to attach metadata > to skbs which would carry the if_id. This way a single xfrm interface in > collect_md mode can demux traffic based on this configuration on tx and > provide this metadata on rx. > > The XFRM metadata is somewhat similar to ip tunnel metadata in that it > has an "id", and shares similar configuration entities (bpf, tc, ...), > however, it does not necessarily represent an IP tunnel or use other > ip tunnel information, and also has an optional "link" property which > can be used for affecting underlying routing decisions. > > Additional xfrm related criteria may also be added in the future. > > Therefore, a new metadata type is introduced, to be used in subsequent > patches in the xfrm interface and configuration entities. > > Reviewed-by: Nikolay Aleksandrov <razor@xxxxxxxxxxxxx> > Signed-off-by: Eyal Birger <eyal.birger@xxxxxxxxx> Reviewed-by: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx>
