Zephyr/NCS BLE Central accepting fixed passkey

RE: Zephyr/NCS BLE Central accepting fixed passkey

Nhuan — Tue, 15 Jun 2021 12:08:38 GMT

Hi Jonas,

How can you create a bond with fixed passkey on peripheral device and phone ?

I'm trying but it is not worked

RE: Zephyr/NCS BLE Central accepting fixed passkey

Einar Thorsrud — Mon, 08 Mar 2021 13:54:13 GMT

There is an error on the peripheral side here, so we need to solve that crash first. Can you start by finding which file/line causes problems by using arm-none-eabi-addr2line -e <project_folder>/build/zephyr/zephyr.elf 0x51308 ? What code do you have on that line? Please share some code amount it as well to provide context, or even better your whole project.

RE: Zephyr/NCS BLE Central accepting fixed passkey

Jonas Lien — Fri, 05 Mar 2021 16:09:43 GMT

Sorry for the late reply, Einar!

Following is what happens on the Peripheral side:

And the Centrals side:

It fails when trying to deal with this custom service I've made. This works when no encryption is enforced, however I've now set it to:

BT_GATT_SERVICE_DEFINE(project_service,
  BT_GATT_PRIMARY_SERVICE(&bt_uuid_project_service),
  BT_GATT_CHARACTERISTIC(&bt_uuid_project_characteristic1.uuid, BT_GATT_CHRC_READ,
                        BT_GATT_PERM_READ_ENCRYPT, read_cb1, NULL, NULL),
  BT_GATT_CHARACTERISTIC(&bt_uuid_project_characteristic2.uuid, BT_GATT_CHRC_READ, 
                        BT_GATT_PERM_READ_ENCRYPT, read_cb2, NULL, NULL),
  BT_GATT_CHARACTERISTIC(&bt_uuid_project_characteristic3.uuid, BT_GATT_CHRC_READ,
                        BT_GATT_PERM_READ_ENCRYPT, read_cb3, NULL, NULL),
  BT_GATT_CHARACTERISTIC(&bt_uuid_project_characteristic4.uuid, BT_GATT_CHRC_READ | BT_GATT_CHRC_WRITE,
                        BT_GATT_PERM_READ_ENCRYPT | BT_GATT_PERM_WRITE_ENCRYPT, read_cb4, write_cb4, NULL),
  BT_GATT_CHARACTERISTIC(&bt_uuid_project_characteristic5.uuid, BT_GATT_CHRC_READ | BT_GATT_CHRC_WRITE,
                        BT_GATT_PERM_READ_ENCRYPT | BT_GATT_PERM_WRITE_ENCRYPT, read_cb5, write_cb5, NULL),
);

and the Peripheral breaks down after fulfilling connected():

static void connected(struct bt_conn *conn, uint8_t err)
{
if (err) {
printk("Connection failed (err 0x%02x)\n", err);
} else {
printk("Connected\n");
}

int sec = bt_conn_get_security(conn);
printk("security level is: %d\n", sec); //sec = 1 upon connection

}

To answer your other question, passkey_confirm() doesnt get invoked on the Central either. Just let me know if you'd want me to paste the complete code, I'd just have to rename some variables like I did in the service register function 🙂

RE: Zephyr/NCS BLE Central accepting fixed passkey

Einar Thorsrud — Thu, 25 Feb 2021 14:19:59 GMT

Hi Jonas,

Your code snippets look correct to me. Can you explain in what way it does not work (adding some logging may be useful)? Is passkey_confirm() called at all?

Einar