I'd like to make a feature request for the S110 SoftDevice and the nRF51822 SDK. The problem centers around the inability to use passkey authorization on a device that does not have an LCD screen. In many applications, it is either not possible or not practical to add an LCD, yet some level of security is still required.
I propose that a method be added to the SDK, perhaps like this: sd_ble_gap_sec_params_set_passkey(new_passkey);
This could be called when GAP_EVT_SEC_PARAMS_REQUEST or GAP_EVT_PASSKEY_DISPLAY is processed. Calling sd_ble_gap_sec_params_set_passkey(new_passkey); would overwrite the randomly generated passkey in the SoftDevice with one retrieved from flash memory (for example).
I realize that without internal knowledge of the SoftDevice, this might be a difficult feature to implement, but I really hope that it's possible to add something like this. Without such a feature, the alternatives are: no security; cobbled-together security; or switching to a different chip vendor. I really think the community would be happy to see this feature added. Other than this issue, the nRF51822 has been awesome and I'm really excited to be using it.
