Re: kernel networking stack in userspace

[Antti Kantee <pooka%cs.hut.fi@localhost>]

On Sun Oct 19 2008 at 13:25:58 +0300, Antti Kantee wrote:
> > >Optionally, if wanting to bridge to a real network, execute:
> > >golem> ifconfig bridge0 create
> > >golem> brconfig bridge0 add tap0 add yourrealif0
> > >golem> brconfig bridge0 up
> > >(yes, the first command really is ifconfig, not brconfig)
> > 
> > What about _routing_ between domains?  :)
> 
> All processes using rumpnet have their own routing tables.  Routing
> between these should not be a problem.  E.g., if you have two processes
> using two tap interfaces, and if they are in the same subnet, you can make
> them talk to each other simply by briding the tap interfaces.  If you
> want actual IP routing to happen, you need to configure routing tables.
> I have not yet tested with options GATEWAY, but I don't see why that
> would be a problem.  So, in theory, it should be possible to build a
> quite complex network on one host using a set of processes, virtual
> interfaces and bridges.

I did a minitest for that recently.  I started two endpoint processes
and a third which acted as a router in between.  The router was pretty
simple to write:

        rump_init();
        configure_interfaces();
        pause();

;)