Re: [PATCH 2/2] mac80211: Support tx-hw-crypt with rx-sw-crypt.

[Johannes Berg <johannes@sipsolutions.net>]

On Wed, 2014-01-22 at 16:05 -0800, Ben Greear wrote:

> >> + * @IEEE80211_KEY_FLAG_SW_RX_CRYPT: This flag indicates hardware will not
> >> + *	do any decrypt for received packets, though it may have uploaded
> >> + *	the hardware key to be used for encrypting transmitted frames.
> > 
> > This isn't needed, all you need to do is return 0 from the set_key
> > callback in the driver, without programming the key into the device. And
> > then ignore tkip key updates for such a key.
> 
> I want and need to program the key into the device so that it can do the
> encryption for transmit.  But, I need software to do full decryption on
> receive.

Ok so the "without programming the key into the device" part was iwlwifi
specific (on TX the key is given explicitly with that device.) However,
the same still applies - just replace that by "without enabling it for
RX" or so.

> That is the only way I could get ath10k to do any sort of software crypt,
> and in fact, that is the most efficient way to get the features I need
> so I might try getting ath9k to support the same mode some day...
> 
> I'll be posting ath10k patches to use this soon, but the dark magic
> is down in the firmware in this case.

Ok, whatever, what I'm saying is that mac80211 doesn't care about
whether you enabled the key for RX or not if you return 0 from
set_key(). All it cares about it that if you return 0 the key must be
available for TX. You therefore don't need to make any mac80211 changes.

johannes