Is there a runtime counterpart for CONFIG_BT_SMP_ALLOW_UNAUTH_OVERWRITE?

[whyeye]

Hi, we have a use case where the central might need to re-bond with our peripheral (e.g., after choosing "Forget this device" in phone settings). I have learned that setting CONFIG_BT_SMP_ALLOW_UNAUTH_OVERWRITE=y works for our purposes, however it would be ideal if we can configure this during runtime. Is this possible?

Here is an overview of how I envision our product to work:

• Peripheral normally advertises with flag BT_LE_ADV_OPT_FILTER_CONN thus only allowing whitelisted centrals to connect
• To add a new central, a button needs to be pressed on the peripheral, which sets a 60 second window where the filter accept list is disabled to allow new connections
• Once a new connection has been established, bonding occurs and the central is added to the filter accept list

The problem with CONFIG_BT_SMP_ALLOW_UNAUTH_OVERWRITE=y is that it will always allow the central to re-bond, but our preference is for bonding to take place only after a button has been pressed on our peripheral device. Please feel free to also suggest any alternative approaches that might work better. Many thanks!

[whyeye]

Just a quick bump to see if this is possible?

[JONATHAN LL]

Hi, 

Looking in to your request and will update.

Regards,
Jonathan

[JONATHAN LL]

Update:

You should be able to use this to modify it in to behaving as you want i belive.

    if (!IS_ENABLED(CONFIG_BT_SMP_ALLOW_UNAUTH_OVERWRITE) &&

        (!(keys->flags & BT_KEYS_AUTHENTICATED)

         && smp->method == JUST_WORKS)) {

        return false;

    }

If this does not work then pleas update and we will see if we are able to figure something out together.

Regards,
Jonathan