1flowi structure:
   3The secid member in the flow structure is used in LSMs (e.g. SELinux) to indicate
   4the label of the flow. This label of the flow is currently used in selecting
   5matching labeled xfrm(s).
   7If this is an outbound flow, the label is derived from the socket, if any, or
   8the incoming packet this flow is being generated as a response to (e.g. tcp
   9resets, timewait ack, etc.). It is also conceivable that the label could be
  10derived from other sources such as process context, device, etc., in special
  11cases, as may be appropriate.
  13If this is an inbound flow, the label is derived from the IPSec security
  14associations, if any, used by the packet.
  15 kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.