From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7B507C10F11 for ; Wed, 24 Apr 2019 21:01:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 527C820835 for ; Wed, 24 Apr 2019 21:01:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387985AbfDXVBa (ORCPT ); Wed, 24 Apr 2019 17:01:30 -0400 Received: from s3.sipsolutions.net ([144.76.43.62]:42252 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728550AbfDXVBa (ORCPT ); Wed, 24 Apr 2019 17:01:30 -0400 Received: by sipsolutions.net with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1hJP1E-0007Ny-6j; Wed, 24 Apr 2019 23:01:28 +0200 Message-ID: <2b232d3cd7af0e6ab6e787d94ffad392813d4da0.camel@sipsolutions.net> Subject: Re: [PATCH] mac80211: Set CAN_REPLACE_PTK0 for SW crypto only drivers From: Johannes Berg To: Alexander Wetzel Cc: linux-wireless@vger.kernel.org Date: Wed, 24 Apr 2019 23:01:26 +0200 In-Reply-To: <0e1d8f51-ca1b-a55e-73a1-d4b95fe3f0b5@wetzel-home.de> References: <20190424173246.26421-1-alexander@wetzel-home.de> <45ef6418002ddb01bc99a06a5c52e0dcd30afd4b.camel@sipsolutions.net> <0e1d8f51-ca1b-a55e-73a1-d4b95fe3f0b5@wetzel-home.de> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.5 (3.28.5-2.fc28) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On Wed, 2019-04-24 at 22:58 +0200, Alexander Wetzel wrote: > > > Now I wonder - shouldn't the same A-MPDU issue apply here? After all, if > > you replace the PTK 0 surely you shouldn't use different ones for the > > same frame in an A-MPDU? > > Not from what I found in IEEE 802.11. It's only forbidden to mix keyIDs, > not MPDUs using different keys. And without Extended Key ID the keyID > can only be zero. So from a standard point of view we are ok, no keyID > mixing possible. Yeah, well, the standard probably didn't consider this. From an implementation POV, having two subframes with different keys will not really be possible, *especially* if they have the same key ID. I think this basically was not considered in spec writing. > From a practical point of view cards like mvm cards will for sure > corrupt MPDUs aggregated in a A-MPDU when different key were used for > them. But we still don't care:-) > > We'll corrupt the MPDU's encoded with either the old or the new key > anyhow and we don't care which ones. After all the card will only have > one key active for key ID 0 at any time won't have the second key > installed at all. Yeah, ok, fair point. johannes