Add BabbleSim tests for VS write BD addr functionality

[Copilot]

Adds test coverage for setting public address via HCI Vendor-Specific bt_hci_cp_vs_write_bd_addr command during bt_enable(), introduced in zephyrproject-rtos#103753.

Changes

Test Scenario 1: Central with public address

• test_central_connect_vs_set_public_addr in main.c - Creates public identity with bt_id_create() before bt_enable() to trigger VS write BD addr path, then connects to peripheral with random address
• tests_scripts/run_central_vs_set_public_addr.sh - BabbleSim test runner

Test Scenario 2: Peripheral with public address

• test_peripheral_vs_set_public_addr in dummy_peripheral.c - Peripheral creates public identity with bt_id_create() before bt_enable() to trigger VS write BD addr path, then advertises
• test_central_connect_to_peripheral_public_addr in main.c - Central connects to the peripheral with public address
• tests_scripts/run_central_connect_to_peripheral_public_addr.sh - BabbleSim test runner

Test infrastructure:

• Enabled CONFIG_BT_HCI_VS=y in prj.conf

Test flow

Scenario 1 - Central with public address:

/* Central creates public address identity before bt_enable() */
bt_addr_le_t addr = {.type = BT_ADDR_LE_PUBLIC,
                     .a.val = {0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF}};

err = bt_id_create(&addr, NULL);
/* bt_enable() triggers hci_vs_write_bd_addr() internally */
err = bt_enable(NULL);

/* Verify by connecting to peripheral with random address */
err = bt_conn_le_create(&peer, &create_param, ...);

Scenario 2 - Peripheral with public address:

/* Peripheral creates public address identity before bt_enable() */
bt_addr_le_t addr = {.type = BT_ADDR_LE_PUBLIC,
                     .a.val = {0x11, 0x22, 0x33, 0x44, 0x55, 0x66}};

err = bt_id_create(&addr, NULL);
/* bt_enable() triggers hci_vs_write_bd_addr() internally */
err = bt_enable(NULL);

/* Central connects to this peripheral */
err = bt_conn_le_create(&peer, &create_param, ...);

Tests registered in test_def[] arrays, following existing BabbleSim test patterns.

Original prompt

Context

PR zephyrproject-rtos#103753 adds support for using the HCI Vendor-Specific command bt_hci_cp_vs_write_bd_addr to set the public address during bt_enable(). This replaces the previous approach of using bt_hci_driver_api::setup which didn't work well in split builds.

The key changes in that PR are:

1. New macro BT_VS_CMD_WRITE_BD_ADDR(cmd) in include/zephyr/bluetooth/hci_vs.h
2. New function hci_vs_write_bd_addr() in subsys/bluetooth/host/hci_core.c that sends the VS command
3. In hci_init(), after hci_vs_init(), if there's a pre-configured public address and the VS write BD addr command is supported, it sends the address via the VS command
4. bt_id_create() in subsys/bluetooth/host/id.c now allows public addresses when CONFIG_BT_HCI_VS is enabled (not just CONFIG_BT_HCI_SET_PUBLIC_ADDR)

Task

Add new BabbleSIM tests to tests/bsim/bluetooth/host/central/ to verify the VS write BD addr functionality. Take inspiration from the existing run_central_connect_to_existing.sh test and the test infrastructure already in place.

Existing test structure to follow

The test lives in tests/bsim/bluetooth/host/central/ with:

• src/main.c - Contains test functions and test installer
• src/dummy_peripheral.c - Contains a simple connectable peripheral
• tests_scripts/run_central_connect_to_existing.sh - Shell script that runs central + peripheral + PHY simulator
• prj.conf - Project configuration
• CMakeLists.txt - Build configuration
• testcase.yaml - Test case metadata

What to add

1. New test function in tests/bsim/bluetooth/host/central/src/main.c:

   • Add a new test test_central_connect_vs_set_public_addr that:
     • Creates a public address identity using bt_id_create() with BT_ADDR_LE_PUBLIC type BEFORE calling bt_enable(). Use an address like {.type = BT_ADDR_LE_PUBLIC, .a.val = {0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF}}
     • Calls bt_enable(NULL) - this should trigger the VS write BD addr path internally
     • Connects to the dummy peripheral (similar to test_central_connect_to_existing)
     • Verifies successful connection
     • Passes the test
   • Register the new test in the test_def[] array with test_id = "central_vs_set_public_addr"

2. New test script tests/bsim/bluetooth/host/central/tests_scripts/run_central_vs_set_public_addr.sh:

   • Follow the exact same pattern as run_central_connect_to_existing.sh:

   #!/usr/bin/env bash
   # Copyright (c) 2026 Nordic Semiconductor
   # SPDX-License-Identifier: Apache-2.0
   
   source ${ZEPHYR_BASE}/tests/bsim/sh_common.source
   
   simulation_id="central_vs_set_public_addr"
   verbosity_level=2
   
   cd ${BSIM_OUT_PATH}/bin
   
   Execute ./bs_${BOARD_TS}_tests_bsim_bluetooth_host_central_prj_conf \
     -v=${verbosity_level} -s=${simulation_id} -d=0 -testid=central_vs_set_public_addr
   
   Execute ./bs_${BOARD_TS}_tests_bsim_bluetooth_host_central_prj_conf \
     -v=${verbosity_level} -s=${simulation_id} -d=1 -testid=peripheral_dummy
   
   Execute ./bs_2G4_phy_v1 -v=${verbosity_level} -s=${simulation_id} \
     -D=2 -sim_length=60e6 $@
   
   wait_for_background_jobs

Reference: Existing run_central_connect_to_existing.sh

#!/usr/bin/env bash
# Copyright (c) 2024 Nordic Semiconductor
# SPDX-License-Identifier: Apache-2.0

source ${ZEPHYR_BASE}/tests/bsim/sh_common.source

simulation_id="central_connect_timeout_to_existing"
verbosity_level=2

cd ${BSIM_OUT_PATH}/bin

Execute ./bs_${BOARD_TS}_tests_bsim_bluetooth_host_central_prj_conf \
  -v=${verbosity_level} -s=${simulation_id} -d=0 -testid=central_connect_to_existing

Execute ./bs_${BOARD_TS}_tests_bsim_bluetooth_host_central_prj_conf \
  -v=${verbosity_level} -s=${simulation_id} -d=1 -testid=peripheral_dummy

Execute ./bs_2G4_phy_v1 -v=${verbosity_level} -s=${simulation_id} \
  -D=2 -sim_length=60e6 $@

wait_for_background_jobs

Reference: Existing src/main.c (relevant parts)

#include "bstests.h"
#include "babblekit/testcase.h"
#include <zephyr/bluetooth/conn.h>
#include <zephyr/bluetooth/hci.h>
#include "common/hci_common_internal.h"
#include "host/conn_internal.h"

struct bst_test_list *test_peripheral_install(struct bst_test_list *tests);

static K_SEM_DEFINE(sem_failed_to_connect, 0, 1);
static K_SEM_DEFINE(sem_connected, 0, 1);

static void connected_cb(struct bt_conn *conn, uint8_t err)
{
	TEST_ASSERT(conn);
	TEST_ASSERT(err == BT_HCI_ERR_SUCCESS, "Expected connection establishment");
	k_sem_give(&sem_connected);
	bt_conn_unref(conn);
}

static struct bt_conn_cb conn_cb = {
	.connected = connected_cb,
};

// ... existing test functions ...

static void test_central_connect_to_existing(void)
{
	int err;
	bt_conn_cb_register(&conn_cb);
	err = bt_enable(NULL);
	TEST_ASSERT(err == 0, "Can't enable Bluetooth (err %d)", err);

	struct bt_conn *conn;
	bt_addr_le_t peer = {.type = BT_ADDR_LE_RANDOM,
			     .a.val = {0xc0, 0xc0, 0xc0, 0xc0, 0xc0, 0xc...

</details>



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[cvinayak]

@copilot add a new test in dummy_peripheral.c file too where in public address is used by peripheral and central connects to it.

[Copilot]

@copilot add a new test in dummy_peripheral.c file too where in public address is used by peripheral and central connects to it.

Added new tests:

1. test_peripheral_vs_set_public_addr in dummy_peripheral.c - Peripheral uses public address via VS write BD addr
2. test_central_connect_to_peripheral_public_addr in main.c - Central connects to peripheral with public address
3. New test script run_central_connect_to_peripheral_public_addr.sh to run both tests together

The peripheral creates a public address {0x11, 0x22, 0x33, 0x44, 0x55, 0x66} before bt_enable() and the central successfully connects to it.

Committed in 81db14a and 3288bbc.

[cvinayak]

@copilot i have now updated the pull request (force pushed). I added scripts et al to be able to test on nrf5340bsim/nrf5340/cpuapp

[Copilot]

@copilot i have now updated the pull request (force pushed). I added scripts et al to be able to test on nrf5340bsim/nrf5340/cpuapp

Acknowledged. I can see the new files added in e298ddf:

• Kconfig - Kernel configuration
• Kconfig.sysbuild - Sysbuild configuration for nrf5340bsim
• compile.sh - Compilation script
• sysbuild.cmake - Sysbuild CMake configuration for HCI IPC network core

The test infrastructure I added (test functions and scripts) is still intact and will now work with nrf5340bsim/nrf5340/cpuapp builds.