timeslot for ccm encryption

[abyr]

I want to secure advertised packets using ccm 

I am using s132 , SDK 14.2.0  and nrf52 dk

I found that AES-CCM peripheral is blocked by soft device usage and that I need to use Time slot APi

I was referring to this to do so.

EDIT:

I can not perform the changes that should be done in the main file. In fact, in my project I do not have the function stated below nor any of the called functions. I was thinking to create it but I do not know how to use it later. My start point is the beacon application.

And I can not find the files softdevice_handler.h and softdevice_handler.c in the directory of nRF5_SDK_14.2.0_17b948a . I have researched this file and it seems that it is an API for initializing and disabling the SoftDevice so it is mandaory but I can not find it what should I do 

static void sys_evt_dispatch(uint32_t sys_evt)
{
    pstorage_sys_event_handler(sys_evt);
    ble_advertising_on_sys_evt(sys_evt);
}

[Sigurd]

Hi,

After the SoftDevice is enabled, the only way to use the CCM is in a timeslot.

Another option is to use the ECB peripheral instead of the CCM, then you can use the softdevice API, and you don't need to use the timeslot API. This use-case is discussed in e.g. this post.

[abyr]

hi I have edited the question it was unclear 

[Sigurd]

Hi,

sys_evt_dispatch is removed and deprecated starting from SDK 14, it's replaced with observers. See this link.

[Sigurd]

Do you need to use the CCM, or can you use the ECB ?

If you don't plan on changing the advertising data after you start advertising, then you can also use CCM to encrypt the advertising packet before you enable the SoftDevice. If you plan on regularly changing the advertising data, and if you 100% need to use the CCM, then I can create an timeslot+CCM example for you.

[abyr]

I need the example and thanks

[Sigurd]

Ok, what SDK version AND toolchain(Segger Embedded Studio,Keil,gcc,IAR,etc) do you want the example in ?

[abyr]

segger embedded studio

sdk14.2.0

[Sigurd]

Hi,

Here the timeslot tutorial you linked to, but with SDK 14.2:

ble_app_beacon_timeslot_tutorial_sdk14_2.rar

Here is a more complex timeslot implementation using this implemenation.

ble_app_beacon_raal_timeslot.rar

Here is timeslot tutorial + added some ESB + CCM code from this repo. Note that it might need some adjusting on how often it request a timeslot.

ble_app_beacon_timeslot_esb_experimental.rar

Again, not sure if CCM is what you are really after, it could be that ECB is better suited for what you are making.

[abyr]

would you explain why ECB is better suited for doing this ??