Am 15.02.19 um 12:52 schrieb Johannes Berg:
On Sun, 2019-02-10 at 22:06 +0100, Alexander Wetzel wrote:
This is not ready for merge and has known issues.
The patch is only for discussions to sort out how to handle it correctly!
Signed-off-by: Alexander Wetzel <alexander@xxxxxxxxxxxxxx>
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iwlwifi intel cards had two big surprises:
Assuming I did not make some stupid errors it looks like my old
"Intel Corporation Centrino Ultimate-N 6300 (rev 3e)" using ucode
9.221.4.1 build 25532 is perfectly fine with two keys uploaded to
harware and honoring the keyid in the MPDUs. For a card launched 2011
that's a pleasant surprise:-)
:-)
A much shorter test with a modern "Intel Corporation Wireless 8265 /
8175 (rev 78)" using ucode version 36.e91976c0.0 shows what seems to be
MPDUs decoded with the wrong key at each rekey and therefore a candidate
for the COMPAT support only..
So the bad news seems to be, that the modern card dropped the support.
Probably just a firmware bug.
It also seems to force us to add some per-card or per-firmware depending
check to decide which card can use the Native Extended Key ID support
and use the Compat mode for the rest.
Is there any way to find out which cards/firmware can be used with
Extended Key ID?
No, but if you have a good test case we can check out what the firmware
bug is and fix it. Perhaps not for all, but for the future at least.
Maybe we can still figure out where it was introduced and thus see where
it's good to use native mode.
I'll verify if can reproduce the scrambled packets and will provide a
capture if so. Assuming that confirms the initial finding I'll be able
to reproduce that at will within minutes with access to a test system
having a mvm card. (I have some plans which will improve access, but
looks like that will take some time and efforts.)
For now I handle that as low prio till we have generic Extended Key ID
support merged and I've had some time to improve my test setup and
hopefully have better access to a mvm card for testing.
I also have tested patch for iwldvm using the Compat mode and I think
mvm cards will also work with that.
No they don't, no firmware is available for that.
So far I only looked at the dvm part of iwlwifi with only minutes spend
on mvm to port the NATIVE solution from dvm.
Are you saying that mvm cards can't seamless switch a RX/TX key to TX
only one? mvm seems to support SW crypto as needed and switching RX/TX
to TX keys is the only other requirement for COMPAT mode.
Alexander
