Hi Archie, On Mon, Nov 15, 2021 at 1:27 AM Archie Pusaka <apusaka@xxxxxxxxxx> wrote: > > From: Archie Pusaka <apusaka@xxxxxxxxxxxx> > > When Remote Name Resolve ends with failure, record this occurrence and > prevent remote name resolving for the same device for some time. > Increase the time duration for subsequent failures. > --- > Hi maintainers, > > This is the patch series for remote name request as was discussed here. > https://patchwork.kernel.org/project/bluetooth/patch/20211028191805.1.I35b7f3a496f834de6b43a32f94b6160cb1467c94@changeid/ > Please also review the corresponding kernel space change. > > Changes in v3: > * Rename MGMT const to align with the doc > > Changes in v2: > * Stay silent instead of sending MGMT_OP_CONFIRM_NAME with DONT_CARE flag. > > lib/mgmt.h | 1 + > src/adapter.c | 15 +++++++++++++-- > src/device.c | 23 +++++++++++++++++++++++ > src/device.h | 2 ++ > 4 files changed, 39 insertions(+), 2 deletions(-) > > diff --git a/lib/mgmt.h b/lib/mgmt.h > index 0d1678f01d..d860b27401 100644 > --- a/lib/mgmt.h > +++ b/lib/mgmt.h > @@ -856,6 +856,7 @@ struct mgmt_ev_auth_failed { > #define MGMT_DEV_FOUND_CONFIRM_NAME 0x01 > #define MGMT_DEV_FOUND_LEGACY_PAIRING 0x02 > #define MGMT_DEV_FOUND_NOT_CONNECTABLE 0x04 > +#define MGMT_DEV_FOUND_NAME_REQUEST_FAILED 0x10 > > #define MGMT_EV_DEVICE_FOUND 0x0012 > struct mgmt_ev_device_found { > diff --git a/src/adapter.c b/src/adapter.c > index d0d38621b8..6100448b5f 100644 > --- a/src/adapter.c > +++ b/src/adapter.c > @@ -6989,6 +6989,7 @@ static void update_found_devices(struct btd_adapter *adapter, > uint8_t bdaddr_type, int8_t rssi, > bool confirm, bool legacy, > bool not_connectable, > + bool name_resolve_failed, > const uint8_t *data, uint8_t data_len) > { > struct btd_device *dev; > @@ -7081,6 +7082,9 @@ static void update_found_devices(struct btd_adapter *adapter, > > device_set_legacy(dev, legacy); > > + if (name_resolve_failed) > + device_name_resolve_fail(dev); > + > if (adapter->filtered_discovery) > device_set_rssi_with_delta(dev, rssi, 0); > else > @@ -7151,7 +7155,10 @@ static void update_found_devices(struct btd_adapter *adapter, > if (g_slist_find(adapter->discovery_found, dev)) > return; > > - if (confirm) > + /* If name is unknown but it's not allowed to resolve, don't send > + * MGMT_OP_CONFIRM_NAME. > + */ > + if (confirm && (name_known || device_name_resolve_allowed(dev))) > confirm_name(adapter, bdaddr, bdaddr_type, name_known); > > adapter->discovery_found = g_slist_prepend(adapter->discovery_found, > @@ -7201,6 +7208,8 @@ static void device_found_callback(uint16_t index, uint16_t length, > uint32_t flags; > bool confirm_name; > bool legacy; > + bool not_connectable; > + bool name_resolve_failed; > char addr[18]; > > if (length < sizeof(*ev)) { > @@ -7230,10 +7239,12 @@ static void device_found_callback(uint16_t index, uint16_t length, > > confirm_name = (flags & MGMT_DEV_FOUND_CONFIRM_NAME); > legacy = (flags & MGMT_DEV_FOUND_LEGACY_PAIRING); > + not_connectable = (flags & MGMT_DEV_FOUND_NOT_CONNECTABLE); > + name_resolve_failed = (flags & MGMT_DEV_FOUND_NAME_REQUEST_FAILED); > > update_found_devices(adapter, &ev->addr.bdaddr, ev->addr.type, > ev->rssi, confirm_name, legacy, > - flags & MGMT_DEV_FOUND_NOT_CONNECTABLE, > + not_connectable, name_resolve_failed, > eir, eir_len); > } > > diff --git a/src/device.c b/src/device.c > index fdc2d50a47..699faeba3b 100644 > --- a/src/device.c > +++ b/src/device.c > @@ -79,6 +79,8 @@ > #define GATT_INCLUDE_UUID_STR "2802" > #define GATT_CHARAC_UUID_STR "2803" > > +#define NAME_RESOLVE_RETRY_DELAY 120 /* seconds */ I'd make this configurable since on headless systems it might be a good idea to have an option to disable the retrying logic. > static DBusConnection *dbus_conn = NULL; > static unsigned service_state_cb_id; > > @@ -272,6 +274,9 @@ struct btd_device { > > GIOChannel *att_io; > guint store_id; > + > + time_t name_resolve_earliest_allow_time; > + uint8_t name_resolve_fail_count; > }; > > static const uint16_t uuid_list[] = { > @@ -4361,6 +4366,24 @@ bool device_name_known(struct btd_device *device) > return device->name[0] != '\0'; > } > > +bool device_name_resolve_allowed(struct btd_device *device) > +{ > + return time(NULL) >= device->name_resolve_earliest_allow_time; > +} > + > +void device_name_resolve_fail(struct btd_device *device) > +{ > + if (!device) > + return; > + > + /* Punish this device by not allowing name resolve for some time. > + * increase punishment time for subsequent failures. > + */ > + device->name_resolve_fail_count++; > + device->name_resolve_earliest_allow_time = time(NULL) + > + NAME_RESOLVE_RETRY_DELAY * device->name_resolve_fail_count; Like I said above we should probably make the number of retries and intervals configurable, have a look how it was done for reconnections in the policy plugin since I believe this would look very similar to that. Anyway we can't really use the system time as that can be modified causing jumps backward or forward in time so you must use CLOCK_MONOTONIC if you don't want it to be affected by system time changes. The other possible solution would be not to have any retry logic since those device are likely to fail resolving their names on each retry, or we are doing this because we now properly abort the name resolution? > +} > + > void device_set_class(struct btd_device *device, uint32_t class) > { > if (device->class == class) > diff --git a/src/device.h b/src/device.h > index 5f615cb4b6..76d79855f8 100644 > --- a/src/device.h > +++ b/src/device.h > @@ -25,6 +25,8 @@ void btd_device_device_set_name(struct btd_device *device, const char *name); > void device_store_cached_name(struct btd_device *dev, const char *name); > void device_get_name(struct btd_device *device, char *name, size_t len); > bool device_name_known(struct btd_device *device); > +bool device_name_resolve_allowed(struct btd_device *device); > +void device_name_resolve_fail(struct btd_device *device); > void device_set_class(struct btd_device *device, uint32_t class); > void device_update_addr(struct btd_device *device, const bdaddr_t *bdaddr, > uint8_t bdaddr_type); > -- > 2.34.0.rc1.387.gb447b232ab-goog > -- Luiz Augusto von Dentz
