Re: [PATCH 2/2] rt2x00: enable experimental MFP with HW crypt

[Stanislaw Gruszka <sgruszka@redhat.com>]

On Wed, Mar 13, 2019 at 02:02:32PM +0100, Tom Psyborg wrote:
> On 13/03/2019, Stanislaw Gruszka <sgruszka@redhat.com> wrote:
> > On Tue, Mar 12, 2019 at 08:11:42PM +0100, Tomislav Požega wrote:
> >> MFP can work with enabled HW crypt engine, but in this case
> >> available bandwidth is reduced at least when connecting to
> >> Archer C7 (QCA9558). Enable the feature for known to work chipsets-
> >> MT7620, RT3070 and RT5390. Userspace setting for ieee80211w should
> >> default to 0 in order to prevent unintentional bandwidth drop.
> >>
> >> Signed-off-by: Tomislav Po?ega <pozega.tomislav@gmail.com>
> >> ---
> >>  drivers/net/wireless/ralink/rt2x00/rt2800lib.c |   11 +++++++----
> >>  1 files changed, 7 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
> >> b/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
> >> index a03b528..bb8204d 100644
> >> --- a/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
> >> +++ b/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
> >> @@ -9326,6 +9326,13 @@ static int rt2800_probe_hw_mode(struct rt2x00_dev
> >> *rt2x00dev)
> >>  	ieee80211_hw_set(rt2x00dev->hw, SIGNAL_DBM);
> >>  	ieee80211_hw_set(rt2x00dev->hw, SUPPORTS_PS);
> >>
> >> +	/* Experimental: Set MFP with HW crypto enabled. */
> >> +	if (rt2x00_rt(rt2x00dev, RT3070) || rt2x00_rt(rt2x00dev, RT5390) ||
> >> +	    rt2x00_rt(rt2x00dev, RT6352))
> >> +		ieee80211_hw_set(rt2x00dev->hw, MFP_CAPABLE);
> >
> > Is not that we support MFP in hardware. We just return -EOPNOTSUPP
> > in rt2x00mac_set_key() when mac80211 will try to set MFP ciphers
> > (since rt2x00crypto_key_to_cipher() will return CIPHER_NONE) and
> > we fallback to software encryption.
> >
> > Please repost patch that enable MFP unconditionally with
> > 'Cc: stable@vger.kernel.org' tag.
> >
> > Stanislaw
> >
> 
> No, I have not test any other chipsets besides the ones I enabled it
> for. It is possible this would cause problems on other devices, so
> just enable it for the known to work ones.

It's just matter of sending already encrypted frames. All chipsets
handle that.

Stanislaw