Hi Alain,
> This change adds support for a configurable eir_max_name_len for
> platforms which requires a larger than 48 bytes complete name in EIR.
>
> From bluetoothctl:
> [bluetooth]# system-alias
> 012345678901234567890123456789012345678901234567890123456789
> Changing 012345678901234567890123456789012345678901234567890123456789
> succeeded
> [CHG] Controller DC:71:96:69:02:89 Alias:
> 012345678901234567890123456789012345678901234567890123456789
>
> From btmon:
> < HCI Command: Write Local Name (0x03|0x0013) plen 248 #109
> [hci0] 88.567990
> Name:
> 012345678901234567890123456789012345678901234567890123456789
>> HCI Event: Command Complete (0x0e) plen 4 #110 [hci0] 88.663854
> Write Local Name (0x03|0x0013) ncmd 1
> Status: Success (0x00)
> @ MGMT Event: Local Name Changed (0x0008) plen 260
> {0x0004} [hci0] 88.663948
> Name:
> 012345678901234567890123456789012345678901234567890123456789
> Short name:
> < HCI Command: Write Extended Inquiry Response (0x03|0x0052) plen 241
> #111 [hci0] 88.663977
> FEC: Not required (0x00)
> Name (complete):
> 012345678901234567890123456789012345678901234567890123456789
> TX power: 12 dBm
> Device ID: Bluetooth SIG assigned (0x0001)
> Vendor: Google (224)
> Product: 0xc405
> Version: 0.5.6 (0x0056)
> 16-bit Service UUIDs (complete): 7 entries
> Generic Access Profile (0x1800)
> Generic Attribute Profile (0x1801)
> Device Information (0x180a)
> A/V Remote Control (0x110e)
> A/V Remote Control Target (0x110c)
> Handsfree Audio Gateway (0x111f)
> Audio Source (0x110a)
>> HCI Event: Command Complete (0x0e) plen 4 #112 [hci0] 88.664874
> Write Extended Inquiry Response (0x03|0x0052) ncmd 1
> Status: Success (0x00)
>
> Reviewed-by: Sonny Sasaka <sonnysasaka@xxxxxxxxxxxx>
> Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
> Signed-off-by: Alain Michaud <alainm@xxxxxxxxxxxx>
>
> ---
>
> include/net/bluetooth/hci_core.h | 1 +
> net/bluetooth/hci_core.c | 1 +
> net/bluetooth/hci_request.c | 29 +++++++++++++++++++++--------
> net/bluetooth/mgmt_config.c | 5 +++++
> 4 files changed, 28 insertions(+), 8 deletions(-)
>
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index bee1b4778ccc..e08f92e7a9ca 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -298,6 +298,7 @@ struct hci_dev {
> __u8 dev_name[HCI_MAX_NAME_LENGTH];
> __u8 short_name[HCI_MAX_SHORT_NAME_LENGTH];
> __u8 eir[HCI_MAX_EIR_LENGTH];
> + __u16 eir_max_name_len;
> __u16 appearance;
> __u8 dev_class[3];
> __u8 major_class;
> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> index 6509f785dd14..b2507bd6613a 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -3536,6 +3536,7 @@ struct hci_dev *hci_alloc_dev(void)
> hdev->adv_instance_cnt = 0;
> hdev->cur_adv_instance = 0x00;
> hdev->adv_instance_timeout = 0;
> + hdev->eir_max_name_len = 48;
>
> hdev->sniff_max_interval = 800;
> hdev->sniff_min_interval = 80;
> diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
> index 7c0c2fda04ad..f4714370b7e7 100644
> --- a/net/bluetooth/hci_request.c
> +++ b/net/bluetooth/hci_request.c
> @@ -578,17 +578,21 @@ static u8 *create_uuid128_list(struct hci_dev *hdev, u8 *data, ptrdiff_t len)
> static void create_eir(struct hci_dev *hdev, u8 *data)
> {
> u8 *ptr = data;
> + u8 size_remaining = HCI_MAX_EIR_LENGTH;
> size_t name_len;
>
> name_len = strlen(hdev->dev_name);
>
> if (name_len > 0) {
> /* EIR Data type */
> - if (name_len > 48) {
> - name_len = 48;
> + if (name_len > min_t(u16, (HCI_MAX_EIR_LENGTH - 2),
> + hdev->eir_max_name_len)) {
> + name_len = min_t(u16, (HCI_MAX_EIR_LENGTH - 2),
> + hdev->eir_max_name_len);
if we have proper input validation we could just skip this hard to read code.
> ptr[1] = EIR_NAME_SHORT;
> - } else
> + } else {
> ptr[1] = EIR_NAME_COMPLETE;
> + }
>
> /* EIR Data length */
> ptr[0] = name_len + 1;
> @@ -596,17 +600,21 @@ static void create_eir(struct hci_dev *hdev, u8 *data)
> memcpy(ptr + 2, hdev->dev_name, name_len);
>
> ptr += (name_len + 2);
> + size_remaining -= (name_len + 2);
> }
>
> - if (hdev->inq_tx_power != HCI_TX_POWER_INVALID) {
> + if (hdev->inq_tx_power != HCI_TX_POWER_INVALID &&
> + size_remaining >= 3) {
> ptr[0] = 2;
> ptr[1] = EIR_TX_POWER;
> ptr[2] = (u8) hdev->inq_tx_power;
>
> ptr += 3;
> + size_remaining -= 3;
> }
>
> - if (hdev->devid_source > 0) {
> + if (hdev->devid_source > 0 &&
> + size_remaining >= 10) {
> ptr[0] = 9;
> ptr[1] = EIR_DEVICE_ID;
>
> @@ -616,11 +624,16 @@ static void create_eir(struct hci_dev *hdev, u8 *data)
> put_unaligned_le16(hdev->devid_version, ptr + 8);
>
> ptr += 10;
> + size_remaining -= 10;
> }
>
> - ptr = create_uuid16_list(hdev, ptr, HCI_MAX_EIR_LENGTH - (ptr - data));
> - ptr = create_uuid32_list(hdev, ptr, HCI_MAX_EIR_LENGTH - (ptr - data));
> - ptr = create_uuid128_list(hdev, ptr, HCI_MAX_EIR_LENGTH - (ptr - data));
> + ptr = create_uuid16_list(hdev, ptr, size_remaining);
> + size_remaining = HCI_MAX_EIR_LENGTH - (ptr - data);
> +
> + ptr = create_uuid32_list(hdev, ptr, size_remaining);
> + size_remaining = HCI_MAX_EIR_LENGTH - (ptr - data);
> +
> + ptr = create_uuid128_list(hdev, ptr, size_remaining);
> }
>
> void __hci_req_update_eir(struct hci_request *req)
> diff --git a/net/bluetooth/mgmt_config.c b/net/bluetooth/mgmt_config.c
> index b30b571f8caf..420ea322a5b7 100644
> --- a/net/bluetooth/mgmt_config.c
> +++ b/net/bluetooth/mgmt_config.c
> @@ -67,6 +67,7 @@ int read_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,
> HDEV_PARAM_U16(0x001a, le_supv_timeout),
> HDEV_PARAM_U16_JIFFIES_TO_MSECS(0x001b,
> def_le_autoconnect_timeout),
> + HDEV_PARAM_U16(0x001c, eir_max_name_len),
We should really have range validation for these parameters. And we should document ranges in mgmt-api.txt as well.
> };
> struct mgmt_rp_read_def_system_config *rp = (void *)params;
>
> @@ -138,6 +139,7 @@ int set_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,
> case 0x0019:
> case 0x001a:
> case 0x001b:
> + case 0x001c:
> if (len != sizeof(u16)) {
> bt_dev_warn(hdev, "invalid length %d, exp %zu for type %d",
> len, sizeof(u16), type);
> @@ -251,6 +253,9 @@ int set_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,
> hdev->def_le_autoconnect_timeout =
> msecs_to_jiffies(TLV_GET_LE16(buffer));
> break;
> + case 0x0001c:
> + hdev->eir_max_name_len = TLV_GET_LE16(buffer);
> + break;
> default:
> bt_dev_warn(hdev, "unsupported parameter %u", type);
> break;
Regards
Marcel
