resolve BLE_GAP_ADDR_TYPE_RANDOM_PRIVATE_RESOLVABLE address without using whitelist advertising

[chd]

Hi there,

Is there any way to resolve a BLE_GAP_ADDR_TYPE_RANDOM_PRIVATE_RESOLVABLE address without using whitelist advertising? If not, I guess I should implement the ah function by myself.

I know that Nordic softdevice certainly has this function implemented. My question is, could I have the access to it?

Thank you for any information

[Ulrich Myhre]

You can do this with the sd_ecb_block_encrypt() function. Here is a quick and dirty example function that checks if a given address matches a given IRK. This assumes the address has the BLE_GAP_ADDR_TYPE_RANDOM_PRIVATE_RESOLVABLE type, and does not handle any errors with the encryption call.

static bool resolve_addr(ble_gap_addr_t * addr, const uint8_t * irk_array)
{
    ble_gap_addr_t tmp_addr = {0};
    nrf_ecb_hal_data_t encryption_data;
    uint32_t errcode;
    uint8_t i;
   
    memcpy(&tmp_addr.addr[3], &addr->addr[3], 3);
    memset(&encryption_data, 0, sizeof(encryption_data));

    /* Reverse the array as ECB expects it in big-endian format */
    for (i=0; i<sizeof(encryption_data.key); i++)
    {
        encryption_data.key[i] = irk_array[sizeof(encryption_data.key)-1-i];
        if (i < 3)
        {
            encryption_data.cleartext[15-i] = tmp_addr.addr[3+i];
        }
    }

    errcode = sd_ecb_block_encrypt(&encryption_data);
    for (i=0; i<3; i++)
    {
        tmp_addr.addr[i] = encryption_data.ciphertext[15-i];
    }

    return (memcmp(addr->addr, tmp_addr.addr, sizeof(addr->addr)) == 0);
}

Edit: Indentation is different from the edit mode :(