Static passkey - central and peripheral code issues (NCS connect)

RE: Static passkey - central and peripheral code issues (NCS connect)

Kenneth — Mon, 27 Jan 2025 09:58:46 GMT

Hello,

Please make a new case, since it may not be directly related.

Also, if possible try to attach on-air sniffer log and example on which bt_conn_auth_cb conn_auth_callbacks you have defined on the central and peripheral. For instance one need to be the display and the other the passkey entry.

Kenneth

RE: Static passkey - central and peripheral code issues (NCS connect)

GerardoF — Sat, 25 Jan 2025 02:49:35 GMT

Has anyone been able to fix this issue? I'm using a nRF52 PCA10040 as my central and I always get "Device found: EB:E1:BD:6F:9F:82 (random), RSSI: -56
Found device name: SB-3100043
Matching device found: EB:E1:BD:6F:9F:82 (random). Attempting to connect...
Connection successfully created
Connected
Security level 3 requested (encrypted connection)
[00:00:05.560,272] <err> bt_smp: pairing failed (peer reason 0x8)
Security failed: EB:E1:BD:6F:9F:82 (random) level 1 err 9" Please help

RE: Static passkey - central and peripheral code issues (NCS connect)

lbe — Wed, 28 Jun 2023 13:17:55 GMT

Hello,

Thanks for the suggestion....I'll try to put this in place and come back to you with the results

RE: Static passkey - central and peripheral code issues (NCS connect)

Kenneth — Wed, 28 Jun 2023 11:38:00 GMT

Do you have the possibility to capture an on-air sniffer log?
https://infocenter.nordicsemi.com/topic/ug_sniffer_ble/UG/sniffer_ble/intro.html

After installation you can:
https://infocenter.nordicsemi.com/topic/ug_sniffer_ble/UG/sniffer_ble/action_paired.html

Kenneth

RE: Static passkey - central and peripheral code issues (NCS connect)

lbe — Tue, 27 Jun 2023 13:40:19 GMT

Hello again, thanks for helping out on this.

Actually, I already tried also this combination (I mean, without the CONFIG_BT_FIXED_PASSKEY=y) , but my .passkey_entry callback is never called.

Its code is the following

static void passkey_entry(struct bt_conn *conn)
{
	LOG_INF("Calling Passkey entry\n");
	char addr[BT_ADDR_LE_STR_LEN];
	default_conn = bt_conn_ref(conn);
	bt_addr_le_to_str(bt_conn_get_dst(conn), addr, sizeof(addr));

	unsigned int fixed_passkey = 223344;
	bt_conn_auth_passkey_entry(conn, fixed_passkey);
}

and as shown above it is defined here

static struct bt_conn_auth_cb conn_auth_callbacks = {
	.passkey_entry = passkey_entry,
	.cancel = auth_cancel,
};

I do not seem to ever reach this point though, because of the "Security Failed" message following the bt_set_security....

RE: Static passkey - central and peripheral code issues (NCS connect)

Kenneth — Tue, 27 Jun 2023 13:17:22 GMT

I can see you have CONFIG_BT_FIXED_PASSKEY=y, you should not need that. Since that will be handled by: For the device with passkey entry you will need to register a .passkey_entry callback in conn_auth_callbacks, make sure to call bt_conn_auth_passkey_entry(with 123456) in the callback.

Can you try without?

Kenneth

RE: Static passkey - central and peripheral code issues (NCS connect)

lbe — Tue, 27 Jun 2023 12:31:29 GMT

Yes, this is what I think too....

This is my prj.conf file

#
# Copyright (c) 2018 Nordic Semiconductor
#
# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
#

# Enable the UART driver
CONFIG_UART_ASYNC_API=y
CONFIG_NRFX_UARTE0=y
CONFIG_SERIAL=y
CONFIG_CONSOLE=y
CONFIG_UART_CONSOLE=y

# Enable the BLE stack with GATT Client configuration
CONFIG_BT=y
CONFIG_BT_CENTRAL=y
CONFIG_BT_GATT_CLIENT=y

# Enable the BLE modules from NCS
CONFIG_BT_NUS_CLIENT=y
CONFIG_BT_SCAN=y
CONFIG_BT_SCAN_FILTER_ENABLE=n
CONFIG_BT_GATT_DM=y
CONFIG_HEAP_MEM_POOL_SIZE=2048

# This example requires more workqueue stack
CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=2048

# Enable bonding
CONFIG_BT_SETTINGS=y
CONFIG_FLASH=y
CONFIG_FLASH_PAGE_LAYOUT=y
CONFIG_FLASH_MAP=y
CONFIG_NVS=y
CONFIG_SETTINGS=y

CONFIG_BT_SMP=y
CONFIG_BT_FIXED_PASSKEY=y



# Config logger
CONFIG_LOG=y
CONFIG_USE_SEGGER_RTT=y
CONFIG_LOG_BACKEND_RTT=n
CONFIG_LOG_BACKEND_UART=y

CONFIG_BT_LOG_LEVEL_OFF=y

CONFIG_ASSERT=y

RE: Static passkey - central and peripheral code issues (NCS connect)

Kenneth — Tue, 27 Jun 2023 12:08:54 GMT

What conn_auth_callbacks and conn_auth_info_callbacks have you set on the central?

Edit: Never mind, I can see those above.

Kenneth

RE: Static passkey - central and peripheral code issues (NCS connect)

Kenneth — Tue, 27 Jun 2023 12:07:55 GMT

If the peripheral works with the phone, then the problem here is the central.

Are you sure the central actually support security? What does the prj.conf look like?

RE: Static passkey - central and peripheral code issues (NCS connect)

lbe — Tue, 27 Jun 2023 11:10:53 GMT

I tried, but anything other than BT_SECURITY_L1 gives the same errors.

My impression is that the peripheral awaits for some information that is not sent to it.....

RE: Static passkey - central and peripheral code issues (NCS connect)

Kenneth — Tue, 27 Jun 2023 10:03:39 GMT

Isn't BT_SECURITY_L4 le secure connection? You should likely try BT_SECURITY_L3.

Kenneth

RE: Static passkey - central and peripheral code issues (NCS connect)

lbe — Tue, 27 Jun 2023 09:37:33 GMT

Hello Kenneth, thanks for the pointer, but I already read that discussion and followed the indicated steps.

As of now, I have in fact the peripheral working fine and accepting a static passkey sent using the smartphone app "Nrf Connect".

My problem is when I use a nrf52833DK as a central instead of the smartphone: whatever I try, I get the errors indicated in the original post...It seems that the problems start when I call the

	err = bt_conn_set_security(conn, BT_SECURITY_L4);

which is not accepted by the peripheral....

So, what is the central supposed to send to the peripheral? At what moment should the central send the passkey to validate its connection to the peripheral?

RE: Static passkey - central and peripheral code issues (NCS connect)

Kenneth — Tue, 27 Jun 2023 09:10:58 GMT

Hello,

A long time ago I made an example, likely the example will not compile in new NCS releases, but I would expect the code is readable enough to understand what I did at the time:
https://devzone.nordicsemi.com/f/nordic-q-a/69202/zephyr-ble-static-passkey-between-central-and-peripheral-on-two-nrf52840s

Kenneth