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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D83EC04AA5 for ; Thu, 25 Aug 2022 08:41:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237516AbiHYIlD (ORCPT ); Thu, 25 Aug 2022 04:41:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52500 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239431AbiHYIkn (ORCPT ); Thu, 25 Aug 2022 04:40:43 -0400 Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [217.70.183.198]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1F4297CB46; Thu, 25 Aug 2022 01:40:39 -0700 (PDT) Received: (Authenticated sender: miquel.raynal@bootlin.com) by mail.gandi.net (Postfix) with ESMTPSA id 37767C000B; Thu, 25 Aug 2022 08:40:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1661416837; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Am4LqnkIKE/yX75vRmuOKr2JVZqFlZvk9xmw+zu4JEs=; b=QKZaHy5Zp9xLp6ZqS5O/4VCLkgikspkA5h5FIFggv1CcKPsd1fqjAkvD9DJ6EmrwMUihy6 Q9UF9vLllphu1SIvd7hFRPZ3ldkqZy6XbqTJJ9kQxaRtx+z16ZZssEzDgymOYNq7wHEqG0 mQL+zN7D0p+i6coQ2UQZR5RMBYkbcmDXWf7nuQi7bRYO3R93FvB3sYDWiOUAgvbvF2Gq/4 vN30x/q65YW99kICQI8Fz/nQ7VFfPyT2XD7eX3sIqLQiSWTfwhiLoH3dC70f3lDjyuaIWk aMu4zj1ucE3cg2mUSXs4yl3oPkJ6ehYzibApsIUYqE581VUxYQefpSXV2yW6tg== Date: Thu, 25 Aug 2022 10:40:35 +0200 From: Miquel Raynal To: Alexander Aring Cc: Alexander Aring , Stefan Schmidt , linux-wpan - ML , "David S. Miller" , Jakub Kicinski , Paolo Abeni , Eric Dumazet , Network Development , David Girault , Romuald Despres , Frederic Blain , Nicolas Schodet , Thomas Petazzoni Subject: Re: [PATCH wpan-next 01/20] net: mac802154: Allow the creation of coordinator interfaces Message-ID: <20220825104035.11806a67@xps-13> In-Reply-To: References: <20220701143052.1267509-1-miquel.raynal@bootlin.com> <20220701143052.1267509-2-miquel.raynal@bootlin.com> <20220819191109.0e639918@xps-13> <20220823182950.1c722e13@xps-13> <20220824093547.16f05d15@xps-13> Organization: Bootlin X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-wpan@vger.kernel.org Hi Alexander, aahringo@redhat.com wrote on Wed, 24 Aug 2022 17:43:11 -0400: > On Wed, Aug 24, 2022 at 3:35 AM Miquel Raynal = wrote: > > > > Hi Alexander, > > > > aahringo@redhat.com wrote on Tue, 23 Aug 2022 17:44:52 -0400: > > =20 > > > Hi, > > > > > > On Tue, Aug 23, 2022 at 12:29 PM Miquel Raynal > > > wrote: =20 > > > > > > > > Hi Alexander, > > > > > > > > aahringo@redhat.com wrote on Tue, 23 Aug 2022 08:33:30 -0400: > > > > =20 > > > > > Hi, > > > > > > > > > > On Fri, Aug 19, 2022 at 1:11 PM Miquel Raynal wrote: =20 > > > > > > > > > > > > Hi Alexander, > > > > > > > > > > > > aahringo@redhat.com wrote on Tue, 5 Jul 2022 21:51:02 -0400: > > > > > > =20 > > > > > > > Hi, > > > > > > > > > > > > > > On Fri, Jul 1, 2022 at 10:36 AM Miquel Raynal wrote: =20 > > > > > > > > > > > > > > > > As a first strep in introducing proper PAN management and a= ssociation, > > > > > > > > we need to be able to create coordinator interfaces which m= ight act as > > > > > > > > coordinator or PAN coordinator. > > > > > > > > > > > > > > > > Hence, let's add the minimum support to allow the creation = of these > > > > > > > > interfaces. This might be restrained and improved later. > > > > > > > > > > > > > > > > Signed-off-by: Miquel Raynal > > > > > > > > --- > > > > > > > > net/mac802154/iface.c | 14 ++++++++------ > > > > > > > > net/mac802154/rx.c | 2 +- > > > > > > > > 2 files changed, 9 insertions(+), 7 deletions(-) > > > > > > > > > > > > > > > > diff --git a/net/mac802154/iface.c b/net/mac802154/iface.c > > > > > > > > index 500ed1b81250..7ac0c5685d3f 100644 > > > > > > > > --- a/net/mac802154/iface.c > > > > > > > > +++ b/net/mac802154/iface.c > > > > > > > > @@ -273,13 +273,13 @@ ieee802154_check_concurrent_iface(str= uct ieee802154_sub_if_data *sdata, > > > > > > > > if (nsdata !=3D sdata && ieee802154_sdata_r= unning(nsdata)) { > > > > > > > > int ret; > > > > > > > > > > > > > > > > - /* TODO currently we don't support = multiple node types > > > > > > > > - * we need to run skb_clone at rx p= ath. Check if there > > > > > > > > - * exist really an use case if we n= eed to support > > > > > > > > - * multiple node types at the same = time. > > > > > > > > + /* TODO currently we don't support = multiple node/coord > > > > > > > > + * types we need to run skb_clone a= t rx path. Check if > > > > > > > > + * there exist really an use case i= f we need to support > > > > > > > > + * multiple node/coord types at the= same time. > > > > > > > > */ > > > > > > > > - if (wpan_dev->iftype =3D=3D NL80215= 4_IFTYPE_NODE && > > > > > > > > - nsdata->wpan_dev.iftype =3D=3D = NL802154_IFTYPE_NODE) > > > > > > > > + if (wpan_dev->iftype !=3D NL802154_= IFTYPE_MONITOR && > > > > > > > > + nsdata->wpan_dev.iftype !=3D NL= 802154_IFTYPE_MONITOR) > > > > > > > > return -EBUSY; > > > > > > > > > > > > > > > > /* check all phy mac sublayer setti= ngs are the same. > > > > > > > > @@ -577,6 +577,7 @@ ieee802154_setup_sdata(struct ieee80215= 4_sub_if_data *sdata, > > > > > > > > wpan_dev->short_addr =3D cpu_to_le16(IEEE802154_ADD= R_BROADCAST); > > > > > > > > > > > > > > > > switch (type) { > > > > > > > > + case NL802154_IFTYPE_COORD: > > > > > > > > case NL802154_IFTYPE_NODE: > > > > > > > > ieee802154_be64_to_le64(&wpan_dev->extended= _addr, > > > > > > > > sdata->dev->dev_add= r); > > > > > > > > @@ -636,6 +637,7 @@ ieee802154_if_add(struct ieee802154_loc= al *local, const char *name, > > > > > > > > ieee802154_le64_to_be64(ndev->perm_addr, > > > > > > > > &local->hw.phy->perm_extend= ed_addr); > > > > > > > > switch (type) { > > > > > > > > + case NL802154_IFTYPE_COORD: > > > > > > > > case NL802154_IFTYPE_NODE: > > > > > > > > ndev->type =3D ARPHRD_IEEE802154; > > > > > > > > if (ieee802154_is_valid_extended_unicast_ad= dr(extended_addr)) { > > > > > > > > diff --git a/net/mac802154/rx.c b/net/mac802154/rx.c > > > > > > > > index b8ce84618a55..39459d8d787a 100644 > > > > > > > > --- a/net/mac802154/rx.c > > > > > > > > +++ b/net/mac802154/rx.c > > > > > > > > @@ -203,7 +203,7 @@ __ieee802154_rx_handle_packet(struct ie= ee802154_local *local, > > > > > > > > } > > > > > > > > > > > > > > > > list_for_each_entry_rcu(sdata, &local->interfaces, = list) { > > > > > > > > - if (sdata->wpan_dev.iftype !=3D NL802154_IF= TYPE_NODE) > > > > > > > > + if (sdata->wpan_dev.iftype =3D=3D NL802154_= IFTYPE_MONITOR) > > > > > > > > continue; =20 > > > > > > > > > > > > > > I probably get why you are doing that, but first the overall = design is > > > > > > > working differently - means you should add an additional rece= ive path > > > > > > > for the special interface type. > > > > > > > > > > > > > > Also we "discovered" before that the receive path of node vs > > > > > > > coordinator is different... Where is the different handling h= ere? I > > > > > > > don't see it, I see that NODE and COORD are the same now (bec= ause that > > > > > > > is _currently_ everything else than monitor). This change is = not > > > > > > > enough and does "something" to handle in some way coordinator= receive > > > > > > > path but there are things missing. > > > > > > > > > > > > > > 1. Changing the address filters that it signals the transceiv= er it's > > > > > > > acting as coordinator > > > > > > > 2. We _should_ also have additional handling for whatever the > > > > > > > additional handling what address filters are doing in mac8021= 54 > > > > > > > _because_ there is hardware which doesn't have address filter= ing e.g. > > > > > > > hwsim which depend that this is working in software like other > > > > > > > transceiver hardware address filters. > > > > > > > > > > > > > > For the 2. one, I don't know if we do that even for NODE righ= t or we > > > > > > > just have the bare minimal support there... I don't assume th= at > > > > > > > everything is working correctly here but what I want to see i= s a > > > > > > > separate receive path for coordinators that people can send p= atches to > > > > > > > fix it. =20 > > > > > > > > > > > > Yes, we do very little differently between the two modes, that'= s why I > > > > > > took the easy way: just changing the condition. I really don't = see what > > > > > > I can currently add here, but I am fine changing the style to e= asily > > > > > > show people where to add filters for such or such interface, bu= t right > > > > > > now both path will look very "identical", do we agree on that? = =20 > > > > > > > > > > mostly yes, but there exists a difference and we should at least = check > > > > > if the node receive path violates the coordinator receive path and > > > > > vice versa. > > > > > Put it in a receive_path() function and then coord_receive_path(), > > > > > node_receive_path() that calls the receive_path() and do the > > > > > additional filtering for coordinators, etc. > > > > > > > > > > There should be a part in the standard about "third level filter = rule > > > > > if it's a coordinator". > > > > > btw: this is because the address filter on the transceiver needs = to > > > > > have the "i am a coordinator" boolean set which is missing in this > > > > > series. However it depends on the transceiver filtering level and= the > > > > > mac802154 receive path if we actually need to run such filtering = or > > > > > not. =20 > > > > > > > > I must be missing some information because I can't find any places > > > > where what you suggest is described in the spec. > > > > > > > > I agree there are multiple filtering level so let's go through them= one > > > > by one (6.7.2 Reception and rejection): > > > > - first level: is the checksum (FCS) valid? > > > > yes -> goto second level > > > > no -> drop > > > > - second level: are we in promiscuous mode? > > > > yes -> forward to upper layers > > > > no -> goto second level (bis) > > > > - second level (bis): are we scanning? > > > > yes -> goto scan filtering > > > > no -> goto third level > > > > - scan filtering: is it a beacon? > > > > yes -> process the beacon > > > > no -> drop > > > > - third level: is the frame valid? (type, source, destination, pan = id, > > > > etc) > > > > yes -> forward to upper layers > > > > no -> drop > > > > > > > > But none of them, as you said, is dependent on the interface type. > > > > There is no mention of a specific filtering operation to do in all > > > > those cases when running in COORD mode. So I still don't get what > > > > should be included in either node_receive_path() which should be > > > > different than in coord_receive_path() for now. > > > > > > > > There are, however, two situations where the interface type has its > > > > importance: > > > > - Enhanced beacon requests with Enhanced beacon filter IE, which as= ks > > > > the receiving device to process/drop the request upon certain > > > > conditions (minimum LQI and/or randomness), as detailed in > > > > 7.4.4.6 Enhanced Beacon Filter IE. But, as mentioned in > > > > 7.5.9 Enhanced Beacon Request command: "The Enhanced Beacon Reque= st > > > > command is optional for an FFD and an RFD", so this series was on= ly > > > > targeting basic beaconing for now. > > > > - In relaying mode, the destination address must not be validated > > > > because the message needs to be re-emitted. Indeed, a receiver in > > > > relaying mode may not be the recipient. This is also optional and= out > > > > of the scope of this series. > > > > > > > > Right now I have the below diff, which clarifies the two path, with= out > > > > too much changes in the current code because I don't really see why= it > > > > would be necessary. Unless you convince me otherwise or read the sp= ec > > > > differently than I do :) What do you think? > > > > =20 > > > > > > "Reception and rejection" > > > > > > third-level filtering regarding "destination address" and if the > > > device is "PAN coordinator". > > > This is, in my opinion, what the coordinator boolean tells the > > > transceiver to do on hardware when doing address filter there. You can > > > also read that up in datasheets of transceivers as atf86rf233, search > > > for I_AM_COORD. =20 > > > > Oh right, I now see what you mean! > > =20 > > > Whereas they use the word "PAN coordinator" not "coordinator", if they > > > really make a difference there at this point..., if so then the kernel > > > must know if the coordinator is a pan coordinator or coordinator > > > because we need to set the address filter in kernel. =20 > > > > Yes we need to make a difference, you can have several coordinators but > > a single PAN coordinator in a PAN. I think we can assume that the PAN > > coordinator is the coordinator with no parent (association-wise). With > > the addition of the association series, I can handle that, so I will > > create the two path as you advise, add a comment about this additional > > filter rule that we don't yet support, and finally after the > > association series add another commit to make this filtering rule real. > > =20 > > > =20 > > > > Thanks, > > > > Miqu=C3=A8l > > > > > > > > --- > > > > > > > > --- a/net/mac802154/rx.c > > > > +++ b/net/mac802154/rx.c > > > > @@ -194,6 +194,7 @@ __ieee802154_rx_handle_packet(struct ieee802154= _local *local, > > > > int ret; > > > > struct ieee802154_sub_if_data *sdata; > > > > struct ieee802154_hdr hdr; > > > > + bool iface_found =3D false; > > > > > > > > ret =3D ieee802154_parse_frame_start(skb, &hdr); > > > > if (ret) { > > > > @@ -203,18 +204,31 @@ __ieee802154_rx_handle_packet(struct ieee8021= 54_local *local, > > > > } > > > > > > > > list_for_each_entry_rcu(sdata, &local->interfaces, list) { > > > > - if (sdata->wpan_dev.iftype !=3D NL802154_IFTYPE_NOD= E) > > > > + if (sdata->wpan_dev.iftype =3D=3D NL802154_IFTYPE_M= ONITOR) > > > > continue; > > > > > > > > if (!ieee802154_sdata_running(sdata)) > > > > continue; > > > > > > > > + iface_found =3D true; > > > > + break; > > > > + } > > > > + > > > > + if (!iface_found) { > > > > + kfree_skb(skb); > > > > + return; > > > > + } > > > > + > > > > + /* TBD: Additional filtering is possible on NODEs and/or CO= ORDINATORs */ > > > > + switch (sdata->wpan_dev.iftype) { > > > > + case NL802154_IFTYPE_COORD: > > > > + case NL802154_IFTYPE_NODE: > > > > ieee802154_subif_frame(sdata, skb, &hdr); > > > > - skb =3D NULL; > > > > + break; > > > > + default: > > > > + kfree_skb(skb); > > > > break; > > > > } =20 > > > > > > Why do you remove the whole interface looping above and make it only > > > run for one ?first found? ? =20 > > > > To reduce the indentation level. > > =20 > > > That code changes this behaviour and I do > > > not know why. =20 > > > > The precedent code did: > > for_each_iface() { > > if (not a node) > > continue; > > if (not running) > > continue; > > > > subif_frame(); > > break; > > } > > > > That final break also elected only the first running node iface. > > Otherwise it would mean that we allow the same skb to be consumed > > twice, which is wrong IMHO? =20 >=20 > no? Why is that wrong? There is a real use-case to have multiple > interfaces on one phy (or to do it in near future, I said that > multiple times). This patch does a step backwards to this. So we need to duplicate the skb because it automatically gets freed in the "forward to upper layer" path. Am I right? I'm fine doing so if this is the way to go, but I am interested if you can give me a real use case where having NODE+COORDINATOR on the same PHY is useful? Thanks, Miqu=C3=A8l