int bt_mesh_lpn_friend_update()

in nimble/host/mesh/src/lpn.c [952:1032]

• 57 lines of code
• 13 McCabe index (conditional complexity)

int bt_mesh_lpn_friend_update(struct bt_mesh_net_rx *rx,
			      struct os_mbuf *buf)
{
	struct bt_mesh_ctl_friend_update *msg = (void *)buf->om_data;
	struct bt_mesh_lpn *lpn = &bt_mesh.lpn;
	struct bt_mesh_subnet *sub = rx->sub;
	uint32_t iv_index;

	if (buf->om_len < sizeof(*msg)) {
		BT_WARN("Too short Friend Update");
		return -EINVAL;
	}

	if (lpn->sent_req != TRANS_CTL_OP_FRIEND_POLL) {
		BT_WARN("Unexpected friend update");
		return 0;
	}

	if (sub->kr_phase == BT_MESH_KR_PHASE_2 && !rx->new_key) {
		BT_WARN("Ignoring Phase 2 KR Update secured using old key");
		return 0;
	}

	if (atomic_test_bit(bt_mesh.flags, BT_MESH_IVU_INITIATOR) &&
	    (atomic_test_bit(bt_mesh.flags, BT_MESH_IVU_IN_PROGRESS) ==
	     BT_MESH_IV_UPDATE(msg->flags))) {
		bt_mesh_beacon_ivu_initiator(false);
	}

	if (!lpn->established) {
		/* This is normally checked on the transport layer, however
		 * in this state we're also still accepting flooding
		 * credentials so we need to ensure the right ones (Friend
		 * Credentials) were used for this message.
		 */
		if (!rx->friend_cred) {
			BT_WARN("Friend Update with wrong credentials");
			return -EINVAL;
		}

		lpn->established = 1;

		BT_INFO("Friendship established with 0x%04x", lpn->frnd);

		bt_mesh_hb_feature_changed(BT_MESH_FEAT_LOW_POWER);

		if (lpn_cb) {
			lpn_cb(lpn->frnd, true);
		}

		/* Set initial poll timeout */
		lpn->poll_timeout = MIN(POLL_TIMEOUT_MAX(lpn),
					POLL_TIMEOUT_INIT);
	}

	friend_response_received(lpn);

	iv_index = sys_be32_to_cpu(msg->iv_index);

	BT_DBG("flags 0x%02x iv_index 0x%08x md %u", msg->flags,
	       (unsigned) iv_index, msg->md);

	bt_mesh_kr_update(sub, BT_MESH_KEY_REFRESH(msg->flags), rx->new_key);
	bt_mesh_net_iv_update(iv_index, BT_MESH_IV_UPDATE(msg->flags));

	if (lpn->groups_changed) {
		sub_update(TRANS_CTL_OP_FRIEND_SUB_ADD);
		sub_update(TRANS_CTL_OP_FRIEND_SUB_REM);

		if (!lpn->sent_req) {
			lpn->groups_changed = 0;
		}
	}

	if (msg->md) {
		BT_DBG("Requesting for more messages");
		send_friend_poll();
	}

	return 0;
}