Get entered passcode

[Elias Löwe]

Hello!

I have a custom board with nRF52810 and s132. BLE connection is secured with passcode. it works.

I would like to get exact passcode entered by User if the passcode is wrong. Is it possible and how?

Thanks in advance

[awneil]

Is the code being entered on your device?

• If yes - then you have control, and can "get" whatever you want.
• If no - then you will have to ask the device developer; but it seems highly unlikely.

[Elias Löwe]

Yes, it is my device. I can not find which event of PM I have to handle and how I can get entered code.

[awneil]

Surely, you must know how the code is entered?

You must have provided the code which reads whatever input device is used?

If you don't know - when it's your device - how can anyone else possibly know?! 

[Elias Löwe]

Let me clarify it:

1. I have nRF52840 board with NUS service and BLE connection requires passcode

2. I connect to the device using lets say iPhone and nRF Connect or Bluefruit app.

3. iOS asks for passcode, I enter some, lets say `123456`

4. Right passcode on the device is `654321`

5. So I get the PM_EVT_CONN_SEC_FAILED event on device side with mesage

<info> peer_manager_handler: Connection security failed: role: Peripheral, conn_handle: 0x0, procedure: Bonding, error: 132

<warning> peer_manager_handler: Disconnecting conn_handle 0.

6. It is absolutely correct workflow but I would like to know in the firmware, that user entered `123456`, not just that it was wrong.

Is it possible?

[Einar Thorsrud]

Hi,

There is no possibility to get this information from the SoftDevice. The only thing you get is a BLE_GAP_EVT_KEY_PRESSED every time a key is pressed on the peer when using LESC, but there is no way to know which number was entered or the full passkey.

[William.wei]

hi Einar,

      Can you instruct me how to catch this BLE_GAP_EVT_KEY_PRESSED , i simply add this event in ble_evt_handler, it doesn't work. also can't find out any doc about this in devzone.

Regards,

William.

[William.wei]

i guess this event is from mobile phone, so no message is received by nrf device, right ?

[Einar Thorsrud]

Yes. Sending key press notifications is optional, so if you do not get the event, then it is probably not sent by the phone.