Re: [PATCH wpan-next 0/2] ieee802154: Beaconing support

Hi,

On Mon, Jan 23, 2023 at 7:49 AM Miquel Raynal [off-list ref] wrote:

Hi Alexander,

quoted

quoted

btw: what is about security handling... however I would declare this
feature as experimental anyway.

I haven't tested the security layer at all yet, would you have a few
commands to start with, which I could try using eg. hwsim?

Using the dev_queue_xmit() doest not bypasses the whole stack anymore,
the beacons got rejected by the llsec layer. I did just hack into it
just to allow unsecure beacons for now:

Stupid questions: do the beacon frames need to be encrypted? Because
we bypass llsec always with those mlme functionality.

btw: there is currently an issue with the llsec hooks. You will not
see the transmit side being encrypted via wireshark (so far I
remember) because the capture is before encryption...

-       if (hlen < 0 || hdr.fc.type != IEEE802154_FC_TYPE_DATA)
+       if (hlen < 0 ||
+           (hdr.fc.type != IEEE802154_FC_TYPE_DATA &&
+            hdr.fc.type != IEEE802154_FC_TYPE_BEACON))
                return -EINVAL;

I believe that would be enough as a first step, at least for merging
beacons support for now.

ok.

However I'll have to look at the spec about security stuff and
beaconing to know how to handle this properly if security was required,
but could you drive me through useful resources were I could quickly
grasp how all that works? Did you make any presentation of it? Perhaps
just a blog post or something alike? Or even just a script showing its
use?

I am pretty sure I have something... you need to construct an ACL
there and there exist different methods to do a key lookup. Some are
very easy and some are more difficult to set up. I will look later...
or just do a setup again with hwsim with should work (but again don't
trust wireshark/tcpdump).

Also note: currently there exists practical issues on 802.15.4 stack
(but star topology kind of solves it, so far I understood) to
synchronize security parameters e.g. frame counter.

While I was looking at linux-wpan.org, I realized we should both
contribute to it with some examples about security stuff and
beaconing/scanning?

yes, that would be nice... I am pretty sure there are some examples on
the mailinglist archive.

- Alex