How to set up BLE bonding

[StefXinet]

Dear Nordic,

we are devepoling FW based on nRF52832, SDK 17.0.2. We have 2 devices:

BLE Central with SD S332

BLE Peripheral with SD S112

We setted up an open BLE communication, the data are exchanging fine. At this development stage we need to add the bonding feature because we need a thrusted communication between central an peripheral.

Could you please suggest us some clear documentation on how to set up the peer manager link well?

There are many questions here on the forum but unfortunately there are no adequate answers for our case. Could you give us the correct links to the documentation?
Please don't tell us to use your examples, we'd rather read a guide with clear explanations rather than having to debug examples that have little documentation.

Thanks for your help!

[Kenneth]

Hello,

You can find documentation for peer manager here:
https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.1.0/lib_peer_manager.html

Honestly speaking, if you want to support bonding, then I strongly recommend that you start with an existing application that already support bonding (peer manager), and include the services and characteristics you want to that application (or even update the softdevice header files and ram/flash usage due to a different softdevice), instead of the other way around. The peer manager module have a lot of depencies and defines, and including all those to a new project is not something I recommend. Instead the nRF5 SDK have already done the work for you by providing applications that support bonding.

Best regards,
Kenneth

[StefXinet]

Kenneth said:

You can find documentation for peer manager here:
https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.1.0/lib_peer_manager.html

Dear Kenneth,

I'm studying the docs. There is already some peer manager configuration in my code so i fixed it up following the documentation.

I can't understand the parameters for "ble_gap_sec_params_t" settings struct:

referring to Peer Manager - Usage - Security parameters there is some common configurations. I'm using the "Just Works bonding" settings and I can see my device advertising, when I connect it shows all the characteristic and I can read/write them without bonding my device with my phone.

What are the right parameters to allow the connecton only with bonded devices?

Thanks!

[StefXinet]

Thanks for your reply.

I setted BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM in the gap_params_init function but nothing changed:

If I try to connect using nRF connect APP there is no bonding request.

I can also read the device services and characteristic list, and I can read all the characteristics values.

Is there something missing?

[Kenneth]

Maybe they have been previously bonded?

Kenneth

[StefXinet]

No, i'm sure. I checked the bonded device list and it's empty.

[Kenneth]

Do you have an on-air sniffer log?

https://www.nordicsemi.com/Products/Development-tools/nRF-Sniffer-for-Bluetooth-LE 

[StefXinet]

unfortunatly I have any sniffer LOG, I'm already reading that tutorial to set up a sniffer

[mrono]

StefXinet said:

I setted BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM in the gap_params_init function

Kenneth said:

Typically when you init the services and characteristics you also define the security requirements to access them

Usually the services and characteristics aren't initialized in gap_params_init. I'm guessing you still have the characteristics set to BLE_GAP_CONN_SEC_MODE_SET_OPEN.

I have a project based on one of the SDK examples, and the only security feature set in gap_params_init is for the device name. So I think you may have only set the requirement for changing the device name.

[Kenneth]

mrono said:

I have a project based on one of the SDK examples, and the only security feature set in gap_params_init is for the device name. So I think you may have only set the requirement for changing the device name.

Good observation, I did not think of that. Yes, he should go into the services_init() and check the permissions set there.