Return-Path: MIME-Version: 1.0 In-Reply-To: References: From: Yunhan Wang Date: Tue, 1 Aug 2017 08:42:38 -0700 Message-ID: Subject: Re: how to add local name in scan response when setting MGMT_ADV_FLAG_LOCAL_NAME in Bluez To: Luiz Augusto von Dentz Cc: "linux-bluetooth@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Luiz Thanks for your reply. I think kernel should support scan response because I am able to set different local name in scan rsp using hci socket instead of Dbus API. Have you ever post your patch or sample code in this thread or any other place? May I have a try on your patch? It would be doable and useful to put Local name change as property, like include tx power, so that we can set it in scan rsp when enabling advertisement. Thanks Best wishes Yunhan On Tue, Aug 1, 2017 at 5:24 AM, Luiz Augusto von Dentz wrote: > Hi Yunhan, > > On Tue, Aug 1, 2017 at 1:48 PM, Luiz Augusto von Dentz > wrote: >> Hi Yunhan, >> >> On Tue, Aug 1, 2017 at 1:21 PM, Luiz Augusto von Dentz >> wrote: >>> Hi Yunhan, >>> >>> On Tue, Aug 1, 2017 at 10:37 AM, Yunhan Wang wrote= : >>>> Hi >>>> >>>> I am trying to do some small experiments that add local name in the >>>> scan response, should I use data[0] to store both adv_data and >>>> scan_rsp? >>>> >>>> I tried to add local name(=E2=80=99TEST=E2=80=99) in data[0] under >>>> mgmt_cp_add_advertising on >>>> https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/src/advertisin= g.c#n484, >>>> it seems it does not work, any idea? >>> >>> Seems to be a limitation in the kernel, also setting the adapter name >>> doesn't change anything either so it seems it simply does not include >>> any scan response. I guess we would have to add support for that. >> >> Actually the kernel does seem to set the scan response data, but is empt= y: >> >> < HCI Command: LE Set Scan Response Data (0x08|0x0009) plen 32 >> #8499 13:40:40.663565 >> Length: 0 >>> HCI Event: Command Complete (0x0e) plen 4 #8500= 13:40:40.664554 >> LE Set Scan Response Data (0x08|0x0009) ncmd 1 >> Status: Success (0x00) > > Ive sent some patches that should enable to use the local adapter name > in the scan data, if you do intend to use a different name then we > might gonna need to add a different property or rework the IncludeName > to be a string and if empty use the local adapter name. > >>>> Thanks >>>> Best wishes >>>> Yunhan >>>> >>>> static DBusMessage *refresh_advertisement(struct btd_adv_client *clien= t) >>>> { >>>> struct mgmt_cp_add_advertising *cp; >>>> uint8_t param_len; >>>> uint8_t *adv_data; >>>> size_t adv_data_len; >>>> uint32_t flags =3D 0; >>>> >>>> uint8_t scan_rsp[] =3D { >>>> =E2=80=99T=E2=80=99, >>>> =E2=80=99E=E2=80=99, >>>> =E2=80=99S=E2=80=99, >>>> =E2=80=99T=E2=80=99 >>>> }; >>>> size_t scan_rsp_len =3D sizeof(scan_rsp); > > This needs to be in raw scan data format aka TLV. > >>>> DBG("Refreshing advertisement: %s", client->path); >>>> >>>> if (client->type =3D=3D AD_TYPE_PERIPHERAL) >>>> flags =3D MGMT_ADV_FLAG_CONNECTABLE | MGMT_ADV_FLAG_DISCOV | >>>> MGMT_ADV_FLAG_LOCAL_NAME; >>>> >>>> if (client->include_tx_power) >>>> flags |=3D MGMT_ADV_FLAG_TX_POWER; >>>> >>>> adv_data =3D bt_ad_generate(client->data, &adv_data_len); >>>> >>>> if (!adv_data || (adv_data_len > calc_max_adv_len(client, flags))) { >>>> error("Advertising data too long or couldn't be generated."); >>>> >>>> return g_dbus_create_error(client->reg, ERROR_INTERFACE >>>> ".InvalidLength", >>>> "Advertising data too long."); >>>> } >>>> >>>> param_len =3D sizeof(struct mgmt_cp_add_advertising) + adv_data_len + >>>> scan_rsp_len; >>>> >>>> cp =3D malloc0(param_len); >>>> >>>> if (!cp) { >>>> error("Couldn't allocate for MGMT!"); >>>> >>>> free(adv_data); >>>> >>>> return btd_error_failed(client->reg, "Failed"); >>>> } >>>> >>>> cp->flags =3D htobl(flags); >>>> cp->instance =3D client->instance; >>>> cp->adv_data_len =3D adv_data_len; >>>> cp->scan_rsp_len =3D scan_rsp_len; >>>> memcpy(cp->data, adv_data, adv_data_len); >>>> memcpy(cp->data + adv_data_len, scan_rsp_data, scan_rsp_len); >>>> free(adv_data); >>>> >>>> if (!mgmt_send(client->manager->mgmt, MGMT_OP_ADD_ADVERTISING, >>>> client->manager->mgmt_index, param_len, cp, >>>> add_adv_callback, client, NULL)) { >>>> DBG("Failed to add Advertising Data"); >>>> >>>> free(cp); >>>> >>>> return btd_error_failed(client->reg, "Failed"); >>>> } >>>> >>>> free(cp); >>>> >>>> return NULL; >>>> } >>>> >>>> Reference: >>>> In lib/mgmt.h, >>>> >>>> #define MGMT_OP_ADD_ADVERTISING 0x003E >>>> struct mgmt_cp_add_advertising { >>>> uint8_t instance; >>>> uint32_t flags; >>>> uint16_t duration; >>>> uint16_t timeout; >>>> uint8_t adv_data_len; >>>> uint8_t scan_rsp_len; >>>> uint8_t data[0]; >>>> } __packed; >>>> From mgmt-api.txt, I am >>>> >>>> Add Advertising Command >>>> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D >>>> >>>> Command Code: 0x003e >>>> Controller Index: >>>> Command Parameters: Instance (1 Octet) >>>> Flags (4 Octets) >>>> Duration (2 Octets) >>>> Timeout (2 Octets) >>>> Adv_Data_Len (1 Octet) >>>> Scan_Rsp_len (1 Octet) >>>> Adv_Data (0-255 Octets) >>>> Scan_Rsp (0-255 Octets) >>>> =E2=80=A6... >>>> With the Flags value the type of advertising is controlled and >>>> the following flags are defined: >>>> >>>> 0 Switch into Connectable mode >>>> 1 Advertise as Discoverable >>>> 2 Advertise as Limited Discoverable >>>> 3 Add Flags field to Adv_Data >>>> 4 Add TX Power field to Adv_Data >>>> 5 Add Appearance field to Scan_Rsp >>>> 6 Add Local Name in Scan_Rsp >>>> -- >>>> To unsubscribe from this list: send the line "unsubscribe linux-blueto= oth" in >>>> the body of a message to majordomo@vger.kernel.org >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >>> >>> >>> -- >>> Luiz Augusto von Dentz >> >> >> >> -- >> Luiz Augusto von Dentz > > > > -- > Luiz Augusto von Dentz