Re: Adding a parameter to net80211_input?

[David Young <dyoung%pobox.com@localhost>]

On Wed, Sep 03, 2008 at 04:51:54PM +0200, Quentin Garnier wrote:
> On Wed, Sep 03, 2008 at 09:39:31AM -0500, David Young wrote:
> > On Wed, Sep 03, 2008 at 05:52:45AM +0200, Quentin Garnier wrote:
> > > Hi,
> > > 
> > > I've been working on importing support for RALink 2860 devices from
> > > OpenBSD, because that's the WLAN chip the EeeBox has.
> > > 
> > > Like wi(4), this chip is able to do encryption and decryption in the
> > > hardware.  Like wi(4), it has the issue that the net80211 layer isn't
> > > too keen on the idea.
> > 
> > Actually, the net80211 layer *is* keen on the idea.  Maybe it appears
> > otherwise.  Can you say more about that?
> 
> Do you remember the workaround wi(4) has to use not to see F_DROPUNENC
> kill all frames?
> 
> You called it grotty in the first place :)
> http://mail-index.netbsd.org/tech-net/2007/11/26/0005.html

It is grotty.  I do not think that it should be repeated.

> I guess the problem is that just like for wi, the crypto headers are
> lost.

I guess so.  Does the Ralink adapter clear the crypto bit,
IEEE80211_FC1_WEP, or leave it set?  Does it indicate the key number
by using, for example, bits in the rx descriptor?  Is it possible to
program the Ralink adapter to decrypt without removing the WEP header?

I think that the best option is probably to let software do WEP.
Second best option may be to add a capability flag to net80211
(IEEE80211_C_xxx)that tells it that the h/w does the WEP decapsulation,
then fiddle a bit with ieee80211_input().

Dave

-- 
David Young             OJC Technologies
dyoung%ojctech.com@localhost      Urbana, IL * (217) 278-3933 ext 24