kern/63317: make ng_ether(4) support "lower" and "orphans"simultaneously

[Gleb Smirnoff]

The following reply was made to PR kern/63317; it has been noted by GNATS.

From: Gleb Smirnoff <glebius at cell.sick.ru>
To: Archie Cobbs <archie at dellroad.org>
Cc: Maxim Konovalov <maxim at macomnet.ru>,
	bzeeb-lists at lists.zabbadoz.net, FreeBSD-gnats-submit at FreeBSD.ORG
Subject: Re: kern/63317: make ng_ether(4) support "lower" and "orphans"simultaneously
Date: Wed, 28 Apr 2004 11:00:42 +0400

 On Tue, Apr 27, 2004 at 09:18:58AM -0500, Archie Cobbs wrote:
 A> > It is said in current manpage, that ng_ether sends all packets to lower,
 A> > however code reveals the truth. Here is a sniplet from ng_ether_input_orphan(),
 A> > which is a hook called by ethernet stack:
 A> > 
 A> >         /* If "orphan" hook not connected, let packet continue */
 A> >         if (priv->lower == NULL || !priv->lowerOrphan) {
 A> >                 m_freem(m);
 A> >                 return;
 A> >         }
 A> 
 A> What is your point? This function is only called for orphan packets.
 A> In the current code, if the 'lower' hook is connected, this function will
 A> never be called (all packets will get sent to 'lower') (note: in the current
 A> code, 'priv->lower' is used for both 'lower' and 'orphans' hooks).
 
 Yes, you are right. I've looked into if_ethersubr.c and understood this. Sorry.
 I have repeated my experiment, and it showed that all packets are received on lower.
 Yesterday it was a coincidence, that no IPX packet broadcasted during a minute.
 
 A> > A> To preserve the existing behavior, the node would need to duplicate
 A> > A> the orphanable packets and send them to BOTH connected hooks.
 
 What about this behavoir?
 
 - if lower is connected, send ALL packets to it (like now)
 - if orphans is connected send orphaned packets to it (like now)
 - if both are connected, send non-orphaned to lower and orphaned to orphans
 
 Since, the third option is not available now at all, we won't break any current
 configurations.
 
 -- 
 Totus tuus, Glebius.
 GLEBIUS-RIPN GLEB-RIPE