Commit f79fbeab authored by Rubin Gerritsen's avatar Rubin Gerritsen Committed by Christopher Friedt
Browse files

Bluetooth: Host: Allow setting more than 251 bytes of adv data 



When the application sets more than 251 bytes of advertising data,
the data is sent over multiple HCI commands.
This is only allowed if the advertiser is not running
as defined by the HCI specification.

The data is sent to the controller one AD-field at the time.
If an AD-field is larger than BT_HCI_LE_EXT_ADV_FRAG_MAX_LEN,
the data is split over two commands.
This introduces some additional complexity.

Signed-off-by: default avatarRubin Gerritsen <rubin.gerritsen@nordicsemi.no>
parent 0f63d113

subsys/bluetooth/host/adv.c

+127 −10
Original line number Diff line number Diff line
@@ -344,7 +344,7 @@ struct bt_ad { 
	size_t len;

};



static int set_data_add(uint8_t *set_data, uint8_t set_data_len_max,

static int set_data_add_complete(uint8_t *set_data, uint8_t set_data_len_max,

			const struct bt_ad *ad, size_t ad_len, uint8_t *data_len)

{

	uint8_t set_data_len = 0;
@@ -397,7 +397,7 @@ static int hci_set_ad(uint16_t hci_op, const struct bt_ad *ad, size_t ad_len) 
	set_data = net_buf_add(buf, sizeof(*set_data));

	(void)memset(set_data, 0, sizeof(*set_data));



	err = set_data_add(set_data->data, BT_GAP_ADV_MAX_ADV_DATA_LEN,

	err = set_data_add_complete(set_data->data, BT_GAP_ADV_MAX_ADV_DATA_LEN,

				    ad, ad_len, &set_data->len);

	if (err) {

		net_buf_unref(buf);
@@ -407,8 +407,7 @@ static int hci_set_ad(uint16_t hci_op, const struct bt_ad *ad, size_t ad_len) 
	return bt_hci_cmd_send_sync(hci_op, buf, NULL);

}



/* Set legacy data using Extended Advertising HCI commands */

static int hci_set_ad_ext(struct bt_le_ext_adv *adv, uint16_t hci_op,

static int hci_set_adv_ext_complete(struct bt_le_ext_adv *adv, uint16_t hci_op,

				    const struct bt_ad *ad, size_t ad_len)

{

	struct bt_hci_cp_le_set_ext_adv_data *set_data;
@@ -423,7 +422,7 @@ static int hci_set_ad_ext(struct bt_le_ext_adv *adv, uint16_t hci_op, 
	set_data = net_buf_add(buf, sizeof(*set_data));

	(void)memset(set_data, 0, sizeof(*set_data));



	err = set_data_add(set_data->data, BT_HCI_LE_EXT_ADV_FRAG_MAX_LEN,

	err = set_data_add_complete(set_data->data, BT_HCI_LE_EXT_ADV_FRAG_MAX_LEN,

				    ad, ad_len, &set_data->len);

	if (err) {

		net_buf_unref(buf);
@@ -437,6 +436,124 @@ static int hci_set_ad_ext(struct bt_le_ext_adv *adv, uint16_t hci_op, 
	return bt_hci_cmd_send_sync(hci_op, buf, NULL);

}



static int hci_set_adv_ext_fragmented(struct bt_le_ext_adv *adv, uint16_t hci_op,

				      const struct bt_ad *ad, size_t ad_len)

{

	struct bt_hci_cp_le_set_ext_adv_data *set_data;

	struct net_buf *buf;

	int err;



	for (size_t i = 0; i < ad_len; i++) {



		const struct bt_data *data = ad[i].data;



		for (size_t j = 0; j < ad[i].len; j++) {

			size_t len = data[j].data_len;

			uint8_t type = data[j].type;

			size_t offset = 0;



			/* We can't necessarily set one AD field in a single step. */

			while (offset < data[j].data_len) {

				buf = bt_hci_cmd_create(hci_op, sizeof(*set_data));

				if (!buf) {

					return -ENOBUFS;

				}



				set_data = net_buf_add(buf, sizeof(*set_data));

				(void)memset(set_data, 0, sizeof(*set_data));



				set_data->handle = adv->handle;

				set_data->frag_pref = BT_HCI_LE_EXT_ADV_FRAG_DISABLED;



				/* Determine the operation parameter value. */

				if ((i == 0) && (j == 0) && (offset == 0)) {

					set_data->op = BT_HCI_LE_EXT_ADV_OP_FIRST_FRAG;

				} else if ((i == ad_len - 1) && (j == ad[i].len - 1)) {

					/* The last AD field may be split into

					 * one or two commands.

					 */

					if (offset != 0) {

						/* We can always set the data in two operations

						 * Therefore, we know that this is the last.

						 */

						set_data->op = BT_HCI_LE_EXT_ADV_OP_LAST_FRAG;

					} else if (len + 2 <= BT_HCI_LE_EXT_ADV_FRAG_MAX_LEN) {

						/* First part fits. */

						set_data->op = BT_HCI_LE_EXT_ADV_OP_LAST_FRAG;

					} else {

						/* The data must be split into two

						 * commands.

						 */

						set_data->op = BT_HCI_LE_EXT_ADV_OP_INTERM_FRAG;

					}

				} else {

					set_data->op = BT_HCI_LE_EXT_ADV_OP_INTERM_FRAG;

				}



				if (offset == 0) {

					set_data->len = MIN(len + 2,

							    BT_HCI_LE_EXT_ADV_FRAG_MAX_LEN);

				} else {

					/* No need to take min operation here,

					 * as we can always fit the second part.

					 */

					set_data->len = len - offset;

				}



				if (offset == 0) {

					set_data->data[0] = len + 1;

					set_data->data[1] = type;

					memcpy(&set_data->data[2], data[j].data, set_data->len);

					offset += set_data->len - 2;

				} else {

					memcpy(&set_data->data[0], &data[j].data[offset],

					       set_data->len);

					offset += set_data->len;

				}



				err = bt_hci_cmd_send_sync(hci_op, buf, NULL);

				if (err) {

					return err;

				}

			}



		}

	}



	return 0;

}



static int hci_set_ad_ext(struct bt_le_ext_adv *adv, uint16_t hci_op,

			  const struct bt_ad *ad, size_t ad_len)

{

	size_t total_len_bytes = 0;



	for (size_t i = 0; i < ad_len; i++) {

		for (size_t j = 0; j < ad[i].len; j++) {

			total_len_bytes += ad[i].data[j].data_len + 2;

		}

	}



	if ((total_len_bytes > BT_HCI_LE_EXT_ADV_FRAG_MAX_LEN) &&

	    atomic_test_bit(adv->flags, BT_ADV_ENABLED)) {

		/* It is not allowed to set advertising data in multiple

		 * operations while the advertiser is running.

		 */

		return -EAGAIN;

	}



	if (total_len_bytes <= BT_HCI_LE_EXT_ADV_FRAG_MAX_LEN) {

		/* If possible, set all data at once.

		 * This allows us to update advertising data while advertising.

		 */

		return hci_set_adv_ext_complete(adv, hci_op, ad, ad_len);

	} else {

		return hci_set_adv_ext_fragmented(adv, hci_op, ad, ad_len);

	}



	return 0;

}



static int set_ad(struct bt_le_ext_adv *adv, const struct bt_ad *ad,

		  size_t ad_len)

{
@@ -1525,7 +1642,7 @@ int bt_le_per_adv_set_data(const struct bt_le_ext_adv *adv, 
	 */

	cp->op = BT_HCI_LE_PER_ADV_OP_COMPLETE_DATA;



	err = set_data_add(cp->data, BT_HCI_LE_PER_ADV_FRAG_MAX_LEN, &d, 1,

	err = set_data_add_complete(cp->data, BT_HCI_LE_PER_ADV_FRAG_MAX_LEN, &d, 1,

				    &cp->len);

	if (err) {

		return err;

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