Android pairing pop-up appears twice

RE: Android pairing pop-up appears twice

EbonyH — Sun, 10 Mar 2024 07:49:10 GMT

Hi Andreas,

Can you please share the example code to solve the popup twice issue?

Ebony

RE: Android pairing pop-up appears twice

Simonr — Tue, 21 Dec 2021 11:48:07 GMT

Thank you for sharing your solution with us. I'll report your findings internally. Good job! I'm glad you got it working. Just for reference, the security level was set to SEC_MITM previously, correct?

Best regards and happy Holidays,

Simon

RE: Android pairing pop-up appears twice

Andreas48752 — Mon, 20 Dec 2021 15:56:47 GMT

Hi,

well I did test with the delay. My phone says all services are discovered before connection is secured but popup still showed twice.

I found a workaround: I set characteristics read and write access to "SEC_JUST_WORKS". So connection must be secured and mobile will start encryption. Pairing popup only shows once now.

Best regards,

Andreas

RE: Android pairing pop-up appears twice

Simonr — Mon, 13 Dec 2021 11:30:45 GMT

The root cause is that the SoftDevice sends a security request before the remote initiates LL encryption, so the only thing I can think of is to add the delay I mentioned earlier, so that the device has a chance to complete service discovery before this event is called.

Best regards,

Simon

RE: Android pairing pop-up appears twice

Andreas48752 — Sun, 12 Dec 2021 22:32:34 GMT

Hi!

Sorry for the late reply!

Yes, I commented out the pm_handler_on_pm_evt() but then no pairing is done at all.

Till now I don't have a solution for this. I still having two popups or no pairing at all...

Any other toughts on this?

Thanks und best regards,

Andreas

RE: Android pairing pop-up appears twice

Simonr — Fri, 19 Nov 2021 08:19:58 GMT

Have you tried removing (commenting out) a pm_handler_on_pm_evt() call in your application?

Best regards,

Simon

RE: Android pairing pop-up appears twice

Andreas48752 — Thu, 18 Nov 2021 14:50:06 GMT

Hi,

thank you for looking into that again.

I changed my code. Now I invoke "smd_link_secure" a few seconds after mobile gets connected. Now I see "services discovered" on my mobile app before sending "smd_link_secure". I changed to "smd_link_secure":

ble_gap_sec_params_t sec_param;
memset(&sec_param, 0, sizeof(ble_gap_sec_params_t));

// Security parameters to be used for all security procedures.
sec_param.bond = SEC_PARAM_BOND; // =1
sec_param.mitm = SEC_PARAM_MITM; // =0
sec_param.lesc = SEC_PARAM_LESC;// =1

sec_param.keypress = SEC_PARAM_KEYPRESS; // =0
sec_param.io_caps = SEC_PARAM_IO_CAPABILITIES; // =3
sec_param.oob = SEC_PARAM_OOB; // =0
sec_param.min_key_size = SEC_PARAM_MIN_KEY_SIZE; // = 7
sec_param.max_key_size = SEC_PARAM_MAX_KEY_SIZE; // = 16
sec_param.kdist_own.enc = 1;
sec_param.kdist_own.id = 1;
sec_param.kdist_peer.enc = 1;
sec_param.kdist_peer.id = 1;

smd_link_secure(handle, &sec_param, true);

But I still get "PM_EVT_CONN_SEC_PARAMS_REQ" in pm_evt_handler twice after that.

I see pairing popup on mobile after invoking "smd_link_secure" but when I accept that I get the second "PM_EVT_CONN_SEC_PARAMS_REQ " request and after I see this a second pairing popup on the mobile.

It looks like the mobile tries to pair again or use other settings? This is a breakpoint at second "PM_EVT_CONN_SEC_PARAMS_REQ"

I found some who has the same problem, but he also got no answer:

https://stackoverflow.com/questions/67701354/why-do-i-receive-a-message-twice-asking-me-if-i-want-to-pair-with-lesc-just-work

Many thanks on your effort! Maybe you can help further?

Andreas

RE: Android pairing pop-up appears twice

Simonr — Thu, 18 Nov 2021 07:21:45 GMT

We have taken another look at your sniffer trace, and it seems like the peripheral is issuing a security request on connection before the client has a chance to perform service discovery. Are you calling pm_handler_on_pm_evt() from your PM callback? If so, you can try adding a delay using pm_handler_sec_delay_ms or comment out pm_handler_on_pm_evt() entirely.

Best regards,

Simon

RE: Android pairing pop-up appears twice

Amanda Hsieh — Thu, 04 Nov 2021 14:13:43 GMT

Hi,

The second pairing messages window is used to send pairing DHKey Check or not from the mobile. See the Pairing: Just Works procedure.

Our Android expert has no idea about why Android reacts that. You might seek help from other forums as you did.

-Amanda

RE: Android pairing pop-up appears twice

Amanda Hsieh — Thu, 04 Nov 2021 08:00:19 GMT

Hi,

Sorry. It's my tool's issue. After updating the version, I can see the content. I am looking into the log now.

-Amanda

RE: Android pairing pop-up appears twice

Andreas48752 — Wed, 03 Nov 2021 14:17:27 GMT

Hi,

sorry, but the provided log already starts before making the connection. At first you only see advertising packets and around second 9.5 a connection is established.

I don't think another log would be different?

Andreas

RE: Android pairing pop-up appears twice

Amanda Hsieh — Wed, 03 Nov 2021 13:49:30 GMT

Hi,

Please capture the log before starting the connection and upload it again. Thanks.

-Amanda

RE: Android pairing pop-up appears twice

Andreas48752 — Tue, 02 Nov 2021 12:11:18 GMT

Hi,

attached you will find the wireshark trace.

The MAC of the peripheral is C0.E3.F7.8A.4F.76

devzone.nordicsemi.com/.../2604.Trace.pcapng

RE: Android pairing pop-up appears twice

Amanda Hsieh — Tue, 02 Nov 2021 11:58:25 GMT

Hi,

I have updated the link.

Here is the link https://www.nordicsemi.com/Products/Development-tools/nrf-sniffer-for-bluetooth-le again and the documentation https://infocenter.nordicsemi.com/topic/ug_sniffer_ble/UG/sniffer_ble/intro.html.

-Amanda

RE: Android pairing pop-up appears twice

Andreas48752 — Tue, 02 Nov 2021 09:54:00 GMT

Hi Amanda,

thank you for your reply.

Well unfortunately your provided link is broken. I managed to install the sniffer for wireshark but there I only can see advertising packets?

Maybe you can give me more detailed instructions on how to capture that log?

I provided the log of nRF Connect above? Can't you see anything there?

Thanks, Andreas

RE: Android pairing pop-up appears twice

Amanda Hsieh — Mon, 01 Nov 2021 13:53:39 GMT

Hi,

Please kindly provide the sniffer log to help know what happened in the air.

Regards,
Amanda