Re: [PATCH] tcp: efficient port randomisation

On Friday 29 October 2004 19:28, Stephen Hemminger wrote:

Provide port randomization for incoming connections using variation of
existing sequence number hash. Replace tcp_portalloc_lock and
tcp_port_rover with atomic operation to allow better parallelism.

This is based on
http://www.ietf.org/internet-drafts/draft-larsen-tsvwg-port-randomisation-0
0.txt (with confirmation of of no IPR issues).

I have looked through this, and have a few comments:

* It is probably a good strategy to set 'tcp_rover_next' such that
  the next search is resumed from the previous port found to be free.
  (similar to the old algorithm).  I don't see this in your patch,
  but of course I could have missed it.

* connect_port_offset() does not (at least from an algorithm point
  of view) need to return an u32, an u16 is sufficient.


Michael Larsen