| Message ID | 20220825154630.2174742-2-eyal.birger@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | xfrm: support collect metadata mode for xfrm interfaces | expand |
On 25/08/2022 18:46, Eyal Birger wrote: > 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. > > Signed-off-by: Eyal Birger <eyal.birger@gmail.com> > > ---- > > v2: add "link" property as suggested by Nicolas Dichtel > --- > include/net/dst_metadata.h | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
diff --git a/include/net/dst_metadata.h b/include/net/dst_metadata.h index adab27ba1ecb..e4b059908cc7 100644 --- a/include/net/dst_metadata.h +++ b/include/net/dst_metadata.h @@ -9,6 +9,7 @@ enum metadata_type { METADATA_IP_TUNNEL, METADATA_HW_PORT_MUX, + METADATA_XFRM, }; struct hw_port_info { @@ -16,12 +17,18 @@ struct hw_port_info { u32 port_id; }; +struct xfrm_md_info { + u32 if_id; + int link; +}; + struct metadata_dst { struct dst_entry dst; enum metadata_type type; union { struct ip_tunnel_info tun_info; struct hw_port_info port_info; + struct xfrm_md_info xfrm_info; } u; }; @@ -53,6 +60,16 @@ skb_tunnel_info(const struct sk_buff *skb) return NULL; } +static inline struct xfrm_md_info *skb_xfrm_md_info(const struct sk_buff *skb) +{ + struct metadata_dst *md_dst = skb_metadata_dst(skb); + + if (md_dst && md_dst->type == METADATA_XFRM) + return &md_dst->u.xfrm_info; + + return NULL; +} + static inline bool skb_valid_dst(const struct sk_buff *skb) { struct dst_entry *dst = skb_dst(skb); @@ -82,6 +99,9 @@ static inline int skb_metadata_dst_cmp(const struct sk_buff *skb_a, return memcmp(&a->u.tun_info, &b->u.tun_info, sizeof(a->u.tun_info) + a->u.tun_info.options_len); + case METADATA_XFRM: + return memcmp(&a->u.xfrm_info, &b->u.xfrm_info, + sizeof(a->u.xfrm_info)); default: return 1; }
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. Signed-off-by: Eyal Birger <eyal.birger@gmail.com> ---- v2: add "link" property as suggested by Nicolas Dichtel --- include/net/dst_metadata.h | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)