Secure BLE connections in nrf52833

[viswa]

Hi All,

Hope everyone is fine.

I'm using Vs code with nrf Connect sdk v1.9.1 to develope firmware for nrf52833.

Here our device has no display or Keyboard to give input. I want to achieve pairing with external mobile application ex. nrf connect app.

How can we do it?

I have tried with example under the path "v1.9.1\zephyr\samples\bluetooth\peripheral_sc_only", where I found one it uses SECURITYLEVEL_4.

I've copied the example as it, and got following response into my terminal.

Security failed: 65:86:DA:1C:0E:65 (random) level 1 err 8
Pairing Failed (8). Disconnecting.
{Disconnected (reason: 22)}

Please guide me with necessary steps here. Thank you in advance.

[viswa]

Hi Hung Bui

I have tried to add 

Hung Bui said:

use BT_GATT_PERM_READ_ENCRYPT

and removed the below code from callback.

if (bt_conn_set_security(conn, BT_SECURITY_L2)) {
		printf("Failed to set security\n");
	}

Then, it will connect directly without pairing and when I try read ccc characteristic then mobile app starts bonding process, still I get the same timeout response as I got earlier.

[Hung Bui]

Hi, 

Have you tested with the example I provided ? 
Please make sure you erase the chip and remove bond on the phone. 

[viswa]

Hi Hung

I haven't tried you example as it is...but added those parts you mentioned into my code. I will try to build the example you shared and check it.

When mobile tries to connect, there should be some api to respond to that request, what is this api?

I've come across this pairing_accept() from Zephyr Documention, which I see no where used in peripheral_sc_only sample and example you provided.

This function returns following structure.

struct bt_conn_pairing_feat *const feat

Does this have anything to do pairing success?