Hi Daniel,
On Thu, Oct 1, 2020 at 4:05 PM Daniel Winkler <danielwinkler@xxxxxxxxxx> wrote:
>
> This patch calls the new MGMT command to get controller capabilities,
> and parses the min and max LE tx power range when the manager is
> initialized. This will be used to populate a client-facing dbus entry so
> that the client will know the advertising capabilities of the controller
> before registering an advertisement.
>
> This patch is tested by manually verifying the data is parsed correctly
> from the MGMT response.
>
> Reviewed-by: Sonny Sasaka <sonnysasaka@xxxxxxxxxxxx>
> Reviewed-by: Alain Michaud <alainm@xxxxxxxxxxxx>
> ---
>
> Changes in v4:
> - Move tx power range into single capability field
>
> Changes in v3: None
> Changes in v2: None
>
> lib/mgmt.h | 14 ++++++++----
> src/advertising.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++
> tools/btmgmt.c | 12 +++++------
> 3 files changed, 70 insertions(+), 10 deletions(-)
>
> diff --git a/lib/mgmt.h b/lib/mgmt.h
> index 7ab4fb797..f37f7e654 100644
> --- a/lib/mgmt.h
> +++ b/lib/mgmt.h
> @@ -599,10 +599,16 @@ struct mgmt_cp_set_blocked_keys {
> struct mgmt_blocked_key_info keys[0];
> } __packed;
>
> -#define MGMT_OP_READ_SECURITY_INFO 0x0048
> -struct mgmt_rp_read_security_info {
> - uint16_t sec_len;
> - uint8_t sec[0];
> +#define MGMT_CAP_SEC_FLAGS 0x01
> +#define MGMT_CAP_MAX_ENC_KEY_SIZE 0x02
> +#define MGMT_CAP_SMP_MAX_ENC_KEY_SIZE 0x03
> +#define MGMT_CAP_LE_TX_PWR 0x04
> +
> +#define MGMT_OP_READ_CONTROLLER_CAP 0x0048
> +#define MGMT_READ_CONTROLLER_CAP_SIZE 0
> +struct mgmt_rp_read_controller_cap {
> + uint16_t cap_len;
> + uint8_t cap[0];
> } __packed;
>
> #define MGMT_OP_READ_EXP_FEATURES_INFO 0x0049
> diff --git a/src/advertising.c b/src/advertising.c
> index 052964d42..41d0658c8 100644
> --- a/src/advertising.c
> +++ b/src/advertising.c
> @@ -49,6 +49,8 @@ struct btd_adv_manager {
> uint32_t supported_flags;
> unsigned int instance_bitmap;
> bool extended_add_cmds;
> + int8_t min_tx_power;
> + int8_t max_tx_power;
> };
>
> #define AD_TYPE_BROADCAST 0
> @@ -1679,6 +1681,49 @@ static void read_adv_features_callback(uint8_t status, uint16_t length,
> remove_advertising(manager, 0);
> }
>
> +static void read_controller_cap_complete(uint8_t status, uint16_t length,
> + const void *param, void *user_data)
> +{
> + struct btd_adv_manager *manager = user_data;
> + const struct mgmt_rp_read_controller_cap *rp = param;
> + const uint8_t *ptr = rp->cap;
> + size_t offset = 0;
> + uint8_t tag_len;
> + uint8_t tag_type;
> +
> + if (status || !param) {
> + error("Failed to read advertising features: %s (0x%02x)",
> + mgmt_errstr(status), status);
> + return;
> + }
> +
> + if (sizeof(rp->cap_len) + rp->cap_len != length) {
> + error("Controller capabilities malformed, size %lu != %u",
> + sizeof(rp->cap_len) + rp->cap_len, length);
> + return;
> + }
> +
> + while (offset < rp->cap_len) {
> + tag_len = ptr[offset++];
> + tag_type = ptr[offset++];
> +
> + switch (tag_type) {
> + case MGMT_CAP_LE_TX_PWR:
> + if ((tag_len - sizeof(tag_type)) !=
> + 2*sizeof(manager->min_tx_power)) {
> + error("TX power had unexpected length %d",
> + tag_len);
> + break;
> + }
> + memcpy(&manager->min_tx_power, &ptr[offset], tag_len);
> + memcpy(&manager->max_tx_power, &ptr[offset+1], tag_len);
> + }
> +
> + /* Step to the next entry */
> + offset += (tag_len - sizeof(tag_type));
> + }
> +}
> +
> static struct btd_adv_manager *manager_create(struct btd_adapter *adapter,
> struct mgmt *mgmt)
> {
> @@ -1700,6 +1745,8 @@ static struct btd_adv_manager *manager_create(struct btd_adapter *adapter,
> manager->supported_flags = MGMT_ADV_FLAG_LOCAL_NAME;
> manager->extended_add_cmds =
> btd_has_kernel_features(KERNEL_HAS_EXT_ADV_ADD_CMDS);
> + manager->min_tx_power = ADV_TX_POWER_NO_PREFERENCE;
> + manager->max_tx_power = ADV_TX_POWER_NO_PREFERENCE;
>
> if (!g_dbus_register_interface(btd_get_dbus_connection(),
> adapter_get_path(manager->adapter),
> @@ -1716,6 +1763,13 @@ static struct btd_adv_manager *manager_create(struct btd_adapter *adapter,
> goto fail;
> }
>
> + /* Query controller capabilities. This will be used to display valid
> + * advertising tx power range to the client.
> + */
> + mgmt_send(manager->mgmt, MGMT_OP_READ_CONTROLLER_CAP,
> + manager->mgmt_index, 0, NULL,
> + read_controller_cap_complete, manager, NULL);
I'd make this conditional to experimental for now, also don't we need
to check the kernel has support for it?
> return manager;
>
> fail:
> diff --git a/tools/btmgmt.c b/tools/btmgmt.c
> index 48c9e5887..8b1cc4df5 100644
> --- a/tools/btmgmt.c
> +++ b/tools/btmgmt.c
> @@ -1531,7 +1531,7 @@ static void cmd_extinfo(int argc, char **argv)
> static void sec_info_rsp(uint8_t status, uint16_t len, const void *param,
> void *user_data)
> {
> - const struct mgmt_rp_read_security_info *rp = param;
> + const struct mgmt_rp_read_controller_cap *rp = param;
> uint16_t index = PTR_TO_UINT(user_data);
>
> if (status != 0) {
> @@ -1546,7 +1546,7 @@ static void sec_info_rsp(uint8_t status, uint16_t len, const void *param,
> }
>
> print("Primary controller (hci%u)", index);
> - print("\tSecurity info length: %u", le16_to_cpu(rp->sec_len));
> + print("\tSecurity info length: %u", le16_to_cpu(rp->cap_len));
>
> done:
> pending_index--;
> @@ -1589,11 +1589,11 @@ static void sec_index_rsp(uint8_t status, uint16_t len, const void *param,
> if (rp->entry[i].type != 0x00)
> continue;
>
> - if (!mgmt_send(mgmt, MGMT_OP_READ_SECURITY_INFO,
> + if (!mgmt_send(mgmt, MGMT_OP_READ_CONTROLLER_CAP,
> index, 0, NULL, sec_info_rsp,
> UINT_TO_PTR(index), NULL)) {
> - error("Unable to send read_security_info cmd");
> - return bt_shell_noninteractive_quit(EXIT_FAILURE);
> + error("Unable to send read_security_info cmd");
> + return bt_shell_noninteractive_quit(EXIT_FAILURE);
> }
> pending_index++;
> }
> @@ -1615,7 +1615,7 @@ static void cmd_secinfo(int argc, char **argv)
> return;
> }
>
> - if (!mgmt_send(mgmt, MGMT_OP_READ_SECURITY_INFO, mgmt_index, 0, NULL,
> + if (!mgmt_send(mgmt, MGMT_OP_READ_CONTROLLER_CAP, mgmt_index, 0, NULL,
> sec_info_rsp,
> UINT_TO_PTR(mgmt_index), NULL)) {
> error("Unable to send read_security_info cmd");
> --
> 2.28.0.709.gb0816b6eb0-goog
>
--
Luiz Augusto von Dentz
