• Joe Stringer's avatar
    openvswitch: Add conntrack action · 7f8a436e
    Joe Stringer authored
    Expose the kernel connection tracker via OVS. Userspace components can
    make use of the CT action to populate the connection state (ct_state)
    field for a flow. This state can be subsequently matched.
    
    Exposed connection states are OVS_CS_F_*:
    - NEW (0x01) - Beginning of a new connection.
    - ESTABLISHED (0x02) - Part of an existing connection.
    - RELATED (0x04) - Related to an established connection.
    - INVALID (0x20) - Could not track the connection for this packet.
    - REPLY_DIR (0x40) - This packet is in the reply direction for the flow.
    - TRACKED (0x80) - This packet has been sent through conntrack.
    
    When the CT action is executed by itself, it will send the packet
    through the connection tracker and populate the ct_state field with one
    or more of the connection state flags above. The CT action will always
    set the TRACKED bit.
    
    When the COMMIT flag is passed to the conntrack action, this specifies
    that information about the connection should be stored. This allows
    subsequent packets for the same (or related) connections to be
    correlated with this connection. Sending subsequent packets for the
    connection through conntrack allows the connection tracker to consider
    the packets as ESTABLISHED, RELATED, and/or REPLY_DIR.
    
    The CT action may optionally take a zone to track the flow within. This
    allows connections with the same 5-tuple to be kept logically separate
    from connections in other zones. If the zone is specified, then the
    "ct_zone" match field will be subsequently populated with the zone id.
    
    IP fragments are handled by transparently assembling them as part of the
    CT action. The maximum received unit (MRU) size is tracked so that
    refragmentation can occur during output.
    
    IP frag handling contributed by Andy Zhou.
    
    Based on original design by Justin Pettit.
    Signed-off-by: default avatarJoe Stringer <joestringer@nicira.com>
    Signed-off-by: default avatarJustin Pettit <jpettit@nicira.com>
    Signed-off-by: default avatarAndy Zhou <azhou@nicira.com>
    Acked-by: default avatarThomas Graf <tgraf@suug.ch>
    Acked-by: default avatarPravin B Shelar <pshelar@nicira.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    7f8a436e
openvswitch.h 26 KB