Directed advertising with pre-shared IRK

RE: Directed advertising with pre-shared IRK

KAoT — Tue, 03 Jan 2017 09:10:16 GMT

Yep, that's working! I was not aware of the adv_dir_report member of ble_gap_scan_params_t struct. Setting this to one did the trick. Thanks a lot for your help.

RE: Directed advertising with pre-shared IRK

Petter Myhre — Tue, 27 Dec 2016 13:25:52 GMT

Seems to be working.

For the peripheral:

ret_code_t err_code;

const ble_gap_id_key_t m_peer1 = 
{
    .id_info =
    {
        .irk = {0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F},
    }
};

const ble_gap_id_key_t * m_identities[] = {&m_peer1};

err_code = sd_ble_gap_device_identities_set(m_identities, NULL, 1);
APP_ERROR_CHECK(err_code);

ble_gap_addr_t gap_addr = 
{
    .addr_id_peer = 0,
};

ble_gap_adv_params_t adv_params;

memset(&adv_params, 0, sizeof(adv_params));
adv_params.type        = BLE_GAP_ADV_TYPE_ADV_DIRECT_IND; 
adv_params.p_peer_addr = &gap_addr;

err_code = sd_ble_gap_adv_start(&adv_params);
APP_ERROR_CHECK(err_code);

For the central:

uint32_t err_code;

ble_gap_irk_t irk = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};

ble_gap_privacy_params_t privacy_params;
privacy_params.privacy_mode = BLE_GAP_PRIVACY_MODE_DEVICE_PRIVACY;

privacy_params.private_addr_cycle_s = 15*60;
privacy_params.private_addr_type = BLE_GAP_ADDR_TYPE_RANDOM_PRIVATE_RESOLVABLE;
privacy_params.p_device_irk = &irk;

err_code = sd_ble_gap_privacy_set(&privacy_params);
APP_ERROR_CHECK(err_code);

m_scan_param.active   = 0;
m_scan_param.interval = SCAN_INTERVAL;
m_scan_param.window   = SCAN_WINDOW;
m_scan_param.timeout  = 0x0000;

m_scan_param.use_whitelist  = 0;
m_scan_param.adv_dir_report = 1;

err_code = sd_ble_gap_scan_start(&m_scan_param);
APP_ERROR_CHECK(err_code);

RE: Directed advertising with pre-shared IRK

Petter Myhre — Fri, 23 Dec 2016 14:08:42 GMT

Ok. I'll see if I can make a small example. Let me know if you have any news.

RE: Directed advertising with pre-shared IRK

KAoT — Fri, 23 Dec 2016 13:53:40 GMT

I guess you're right, not both should be set. I tested with a private peer + only id_info and static peer + only id_addr_info and it seems to work that way. But still, no connection so far. Initiator replies with a connection request and then seems to stop.

RE: Directed advertising with pre-shared IRK

Petter Myhre — Fri, 23 Dec 2016 12:07:18 GMT

I haven't tested this myself, but I would think it would be something like this:

const ble_gap_id_key_t m_peer1 = {
  .id_info ={
      .irk = {0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F},}
};
const ble_gap_id_key_t * m_identities[] = {&m_peer1};

err_code = sd_ble_gap_device_identities_set(m_identities,NULL,1);
APP_ERROR_CHECK(err_code);

I don't think you should set id_addr_info and id_info.

RE: Directed advertising with pre-shared IRK

KAoT — Thu, 22 Dec 2016 16:37:55 GMT

Thanks for the comment Petter Myhre, I found the part I was missing in your link.

In the scanning device right before starting to scan I've added the advertiser's identity with

const ble_gap_id_key_t m_peer1 = {
  .id_addr_info = {
    .addr_type = BLE_GAP_ADDR_TYPE_RANDOM_STATIC,
    .addr = {0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xfX},},
  .id_info ={
      .irk = {0x00,0x01,0x02,0x03,...,0x0F},}
};
const ble_gap_id_key_t * m_identities[] = {&m_peer1};

sd_ble_gap_device_identities_set(m_identities,NULL,1);

Now the device responds to the advertising, but connection is not possible so far. Interestingly, the address type of the id key must be of type random static in order to make it work, although the advertiser is not using this address type. I'm still confused how I have to set this up correctly.

RE: Directed advertising with pre-shared IRK

Petter Myhre — Wed, 21 Dec 2016 11:21:05 GMT

Maybe try like shown in this MSC instead?