Documentation/netlink/specs/ovs_packet.yaml

# SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)
---
name: ovs_packet
version: 1
protocol: genetlink-legacy
uapi-header: linux/openvswitch.h

doc: |
  OVS packet execution over generic netlink.

  Only OVS_PACKET_CMD_EXECUTE is exposed as a genl operation.
  OVS_PACKET_CMD_MISS and OVS_PACKET_CMD_ACTION are kernel-to-userspace
  upcalls sent via genlmsg_unicast() to the vport's upcall_pid and have
  no associated genl_ops or multicast group.

  Several attributes in the attribute set (userdata, egress-tun-key, len)
  exist for the upcall path and are not used by the EXECUTE operation.
  For EXECUTE, packet, key, and actions are mandatory (kernel returns
  -EINVAL without them).

definitions:
  -
    name: ovs-header
    type: struct
    members:
      -
        name: dp-ifindex
        type: u32

attribute-sets:
  -
    name: packet
    name-prefix: ovs-packet-attr-
    enum-name: ovs-packet-attr
    attributes:
      -
        name: packet
        type: binary
        doc: Packet data, from the start of the Ethernet header.
        checks:
          min-len: 14
      -
        name: key
        type: binary
        doc: |
          Nested OVS_KEY_ATTR_* attributes, extracted flow key.
          Defined as binary because the key attribute-set belongs to the
          ovs_flow family spec; cross-spec references are not supported.
      -
        name: actions
        type: binary
        doc: |
          Nested OVS_ACTION_ATTR_* attributes.
          Defined as binary for the same reason as key.
      -
        name: userdata
        type: binary
        doc: Opaque userspace cookie from OVS_USERSPACE_ATTR_USERDATA.
      -
        name: egress-tun-key
        type: binary
        doc: Nested OVS_TUNNEL_KEY_ATTR_* for output tunnel metadata.
      -
        name: unused1
        type: unused
      -
        name: unused2
        type: unused
      -
        name: probe
        type: flag
        doc: Packet operation is a feature probe, error logging suppressed.
      -
        name: mru
        type: u16
        doc: Maximum received IP fragment size.
      -
        name: len
        type: u32
        doc: Packet size before truncation.
      -
        name: hash
        type: u64
        doc: Packet hash, low 32 bits are skb hash, upper bits are flags.
      -
        name: upcall-pid
        type: u32
        doc: Netlink PID to use for upcalls during EXECUTE processing.

operations:
  fixed-header: ovs-header
  name-prefix: ovs-packet-cmd-
  list:
    -
      name: miss
      doc: Notify userspace of a flow table miss for a received packet.
      value: 1
      attribute-set: packet
      event:
        attributes: &event-attrs
          - packet
          - key
          - userdata
          - actions
          - egress-tun-key
          - mru
          - len
          - hash
    -
      name: action
      doc: Notify userspace as requested by an OVS_ACTION_ATTR_USERSPACE action.
      value: 2
      attribute-set: packet
      event:
        attributes: *event-attrs
    -
      name: execute
      doc: Apply actions to a packet.
      value: 3
      attribute-set: packet
      do:
        request:
          attributes:
            - packet
            - key
            - actions
            - probe
            - mru
            - hash
            - upcall-pid