Subject: Re: setting ethernet interface hardware address?
To: None <firstname.lastname@example.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
Date: 10/16/2001 19:09:59
> Is it possible to set the link layer address on NICs in NetBSD?
It depends on the NIC. Much - most? all? - hardware supports this,
though with varying degrees of ease.
I don't think any drivers currently support it; I certainly know of
none. For a past project, I had occasion to add a kernel-compile-time
option to cause one driver to override the MAC address read from the
card, but it was a major kludge, and worked for that driver only.
Given a reasonably well-thought-out interface, I would guess that
most-to-all ethernet interfaces could be made to handle it.
Of course, if you want to do it for non-Ethernets, it gets more
interesting. Not all network interfaces have software-settable
link-layer addresses; a simple example is SLIP/PPP, for which
link-layer addressing is entirely implicit.
I'd love to see a good interface design for this. Especially if it
also allows fetching the link-layer address; the project I alluded to
above also had occasino to want to fetch an interface's MAC address,
and I found it really gross that I couldn't do that without assuming
something about some other address family. (The program was
AF_INET-dependent anyway, so it wasn't a practical issue, just an
/~\ The ASCII der Mouse
\ / Ribbon Campaign
X Against HTML email@example.com
/ \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B