ZigBee Groups Handler Bug

RE: ZigBee Groups Handler Bug

Alex_T — Tue, 25 Jan 2022 10:38:53 GMT

By coincidence I just found this:

https://devzone.nordicsemi.com/f/nordic-q-a/73876/multi-endpoints-zigbee-device-answers-to-get_group_membership_req-with-the-group-list-of-the-entire-device

It appears to be the same problem but 9 Month ago.

I am confused why this has not been further investigated?

RE: ZigBee Groups Handler Bug

Marte Myrvold — Mon, 17 Jan 2022 13:56:35 GMT

Hi Alex,

Another update from the developers. They confirmed what I said in my previous reply, that group memberships is handled correctly, and that the only issue is the Get Group Membership Response command. View Group command works, so it is possible to use this to check group membership, but this will of course have the same issue as when using zb_aps_is_endpoint_in_group, where you have to check for a specific group ID.

The Get Group Membership bug has been reported to DSR, who are responsible for the ZBOSS stack. The fix should show up in the release notes as ZBS-676.

Best regards,

Marte

RE: ZigBee Groups Handler Bug

Marte Myrvold — Fri, 14 Jan 2022 12:43:19 GMT

Hi Alex,

Sorry for the delay. I have an update from the developers.

They have been able to reproduce the issue and gather some more information regarding it. It seems the issue is with the Get Group Membership Response command, which always returns all groups the device is added to, ignoring the endpoint. By looking at internal logs in the stack they found that adding an endpoint to a group works fine, and sending the Remove Group command from a particular group to and endpoint that is not a member of the group returned that the group was not found. So it seems like group membership is handled correctly otherwise. However, they are still working on this and will keep on testing to make sure that is correct, and to figure out how to solve the issue.

Regarding your question about getting group membership on the device, the developers confirmed that zb_aps_is_endpoint_in_group() is the only option at the moment.

Best regards,

Marte

RE: ZigBee Groups Handler Bug

Marte Myrvold — Thu, 09 Dec 2021 10:09:54 GMT

Hi Alex,

Thank you for the information. I have forwarded it to the developers.

They have not gotten back to me regarding a workaround yet.

Best regards,

Marte

RE: ZigBee Groups Handler Bug

Alex_T — Tue, 07 Dec 2021 11:03:39 GMT

Hi Marte,

I just went back to nRF Connect 1.5.1 (which is the certified zigbee platform).

Unfortunately that version has the same issue. Would be great to get a workaround soon.

Best regards,

Alex

RE: ZigBee Groups Handler Bug

Marte Myrvold — Tue, 07 Dec 2021 10:17:30 GMT

Hi Alex,

The developers are looking into the issue, but it might take some time until they have a fix.

I do not know of any other ways currently. I tested some methods, but eventually ended up with the same issue as you, that the structs and functions in zb_aps.h are not available to the application. I have asked the developers if they know of any ways to get this.

Best regards,

Marte

RE: ZigBee Groups Handler Bug

Alex_T — Fri, 03 Dec 2021 07:46:49 GMT

Hi Marte,

Okay, thank you!

Maybe you know a way for reading a list of existing groups so I can overwrite these commands from my application level?

The zb_apsme_get_group_membership_conf_t & zb_apsme_get_group_membership_request does not seem to be accessible.

As far as I can tell there is only the zb_aps_is_endpoint_in_group function available to access groups. Finding the list of groups would mean checking (bruteforcing) group 0-ffff for membership which is not really an option.

Best regards,

Alex

RE: ZigBee Groups Handler Bug

Marte Myrvold — Tue, 30 Nov 2021 09:54:28 GMT

Hi Alex,

You are correct that making changes to zcl_groups.c would be to change the library. You can read about certification of the Zigbee ZBOSS stack and Zigbee libraries in nRF Connect SDK here: ZBOSS library certification. The ZBOSS stack from DSR is certified together with nRF Connect SDK and Nordic SoCs. This stack is precompiled so part of the stack is not possible to change by the user anyway, and the stack is included as the ZBOSS Zigbee stack library in nrfxlib, so all the files under ncs/nrfxlib/zboss.

I have not heard from the developers yet, but I will let you know as soon as I hear anything.

Best regards,

Marte

RE: ZigBee Groups Handler Bug

Alex_T — Mon, 29 Nov 2021 16:11:49 GMT

Hi Marte,

Great when you can reproduce it now. Looking forward to a workaround for this.

I can change zcl_groups.c to get this fixed but as far as I know this would be "changing the library" which is part of the "certified platform" which would make the certification process complicated?

Where do I actually find out which files belong to the certified platform and which files may be changed?

Best regards,

Alex

RE: ZigBee Groups Handler Bug

Marte Myrvold — Mon, 29 Nov 2021 15:06:55 GMT

Hi Alex,

Thank you for providing the sniffer log, it was very helpful in seeing the behavior you described. I have been able to confirm this on my side, and I also saw that when groupcasting a command the endpoint that was not part of the group the command was sent to would respond with an ACK to the command.

I will report this internally to our developers.

Best regards,

Marte

RE: ZigBee Groups Handler Bug

Alex_T — Mon, 29 Nov 2021 11:58:07 GMT

Hi Marte,

I have modified a devboard as send-tool for sending packets to my DUT-device.

Please find Sniffer logs of what I am doing attached. Key for wireshark ist "7a2cc0bb6504e93b7a55ff79d45569f0".

recommended filter in wireshark: ((!(wpan.frame_type == 0x2)) && !(zbee_aps.type == 0x2)) && !(zbee_nwk.cmd.id == 0x08)

I think the sniffer log is explaining my problem best:

Starting with two identical dimmer endpoints (ep10 and ep11):

- First I verify both are in no group.

- add group id 1 to ep10

- add group id 2 to ep10

- add group id 2 to ep11

- get group membership of ep10 (sending with group count 0 - means return all groups of the entity)

-> ep10 has both groups as expected

- get group membership of ep11 (sending with group count 0 - means return all groups of the entity)

-> ep11 also has both groups!?? -> BUG!

- remove the additinal shown group 1 from ep11

-> ep11 says error that group 1 is not found (on this endpoint)

- verify group membership with get group membership of ep11 (sending with group count 0 - means return all groups of the entity)

-> still says both groups are present on this endpoint

Best regards,

Alex

devzone.nordicsemi.com/.../Groups_5F00_7a2cc0bb6504e93b7a55ff79d45569f0.pcapng

RE: ZigBee Groups Handler Bug

Marte Myrvold — Mon, 29 Nov 2021 10:27:40 GMT

Hi Alex,

Can you share how you are implementing this, especially how you add the endpoint to a group and how you send the get group membership command? Can you also get a sniffer log of when you send the get group membership command and upload it here as a pcap file?

When I tested this myself, only the endpoint with a group membership sent a Get Group Membership Response command.

Best regards,

Marte

RE: ZigBee Groups Handler Bug

Sigurd Hellesvik — Fri, 26 Nov 2021 14:27:30 GMT

Hi Alex

We will look into this, and return to you by the end of Monday

Regards,
Sigurd Hellesvik