2022-02-09 13:07:47

by Joseph Hwang

[permalink] [raw]
Subject: [PATCH v3 1/3] Bluetooth: aosp: surface AOSP quality report through mgmt

When receiving a HCI vendor event, the kernel checks if it is an
AOSP bluetooth quality report. If yes, the event is sent to bluez
user space through the mgmt socket.

Signed-off-by: Joseph Hwang <[email protected]>
Reviewed-by: Archie Pusaka <[email protected]>
---

Changes in v3:
- Rebase to resolve the code conflict.
- Move aosp_quality_report_evt() from hci_event.c to aosp.c.
- A new patch (3/3) is added to enable the quality report feature.

Changes in v2:
- Scrap the two structures defined in aosp.c and use constants for
size check.
- Do a basic size check about the quality report event. Do not pull
data from the event in which the kernel has no interest.
- Define vendor event prefixes with which vendor events of distinct
vendor specifications can be clearly differentiated.
- Use mgmt helpers to add the header and data to a mgmt skb.

include/net/bluetooth/hci_core.h | 5 ++
include/net/bluetooth/mgmt.h | 7 +++
net/bluetooth/aosp.c | 27 ++++++++++
net/bluetooth/aosp.h | 13 +++++
net/bluetooth/hci_event.c | 84 +++++++++++++++++++++++++++++++-
net/bluetooth/mgmt.c | 20 ++++++++
net/bluetooth/msft.c | 14 ++++++
net/bluetooth/msft.h | 12 +++++
8 files changed, 181 insertions(+), 1 deletion(-)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index f5caff1ddb29..ea83619ac4de 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -1864,6 +1864,8 @@ int mgmt_add_adv_patterns_monitor_complete(struct hci_dev *hdev, u8 status);
int mgmt_remove_adv_monitor_complete(struct hci_dev *hdev, u8 status);
void mgmt_adv_monitor_device_lost(struct hci_dev *hdev, u16 handle,
bdaddr_t *bdaddr, u8 addr_type);
+int mgmt_quality_report(struct hci_dev *hdev, void *data, u32 data_len,
+ u8 quality_spec);

u8 hci_le_conn_update(struct hci_conn *conn, u16 min, u16 max, u16 latency,
u16 to_multiplier);
@@ -1882,4 +1884,7 @@ void hci_copy_identity_address(struct hci_dev *hdev, bdaddr_t *bdaddr,

#define TRANSPORT_TYPE_MAX 0x04

+#define QUALITY_SPEC_AOSP_BQR 0x0
+#define QUALITY_SPEC_INTEL_TELEMETRY 0x1
+
#endif /* __HCI_CORE_H */
diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
index 99266f7aebdc..03204b4ba641 100644
--- a/include/net/bluetooth/mgmt.h
+++ b/include/net/bluetooth/mgmt.h
@@ -1120,3 +1120,10 @@ struct mgmt_ev_adv_monitor_device_lost {
__le16 monitor_handle;
struct mgmt_addr_info addr;
} __packed;
+
+#define MGMT_EV_QUALITY_REPORT 0x0031
+struct mgmt_ev_quality_report {
+ __u8 quality_spec;
+ __u32 data_len;
+ __u8 data[];
+} __packed;
diff --git a/net/bluetooth/aosp.c b/net/bluetooth/aosp.c
index 432ae3aac9e3..4a336433180d 100644
--- a/net/bluetooth/aosp.c
+++ b/net/bluetooth/aosp.c
@@ -199,3 +199,30 @@ int aosp_set_quality_report(struct hci_dev *hdev, bool enable)
else
return disable_quality_report(hdev);
}
+
+#define BLUETOOTH_QUALITY_REPORT_EV 0x58
+
+/* The following LEN = 1-byte Sub-event code + 48-byte Sub-event Parameters */
+#define BLUETOOTH_QUALITY_REPORT_LEN 49
+
+bool aosp_check_quality_report_len(struct sk_buff *skb)
+{
+ /* skb->len is allowed to be larger than BLUETOOTH_QUALITY_REPORT_LEN
+ * to accommodate an additional Vendor Specific Parameter (vsp) field.
+ */
+ if (skb->len < BLUETOOTH_QUALITY_REPORT_LEN) {
+ BT_ERR("AOSP evt data len %d too short (%u expected)",
+ skb->len, BLUETOOTH_QUALITY_REPORT_LEN);
+ return false;
+ }
+
+ return true;
+}
+
+void aosp_quality_report_evt(struct hci_dev *hdev, void *data,
+ struct sk_buff *skb)
+{
+ if (aosp_has_quality_report(hdev) && aosp_check_quality_report_len(skb))
+ mgmt_quality_report(hdev, skb->data, skb->len,
+ QUALITY_SPEC_AOSP_BQR);
+}
diff --git a/net/bluetooth/aosp.h b/net/bluetooth/aosp.h
index 2fd8886d51b2..b21751e012de 100644
--- a/net/bluetooth/aosp.h
+++ b/net/bluetooth/aosp.h
@@ -10,6 +10,9 @@ void aosp_do_close(struct hci_dev *hdev);

bool aosp_has_quality_report(struct hci_dev *hdev);
int aosp_set_quality_report(struct hci_dev *hdev, bool enable);
+bool aosp_check_quality_report_len(struct sk_buff *skb);
+void aosp_quality_report_evt(struct hci_dev *hdev, void *data,
+ struct sk_buff *skb);

#else

@@ -26,4 +29,14 @@ static inline int aosp_set_quality_report(struct hci_dev *hdev, bool enable)
return -EOPNOTSUPP;
}

+static inline bool aosp_check_quality_report_len(struct sk_buff *skb)
+{
+ return false;
+}
+
+static inline void aosp_quality_report_evt(struct hci_dev *hdev, void *data,
+ struct sk_buff *skb)
+{
+}
+
#endif
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 63b925921c87..6468ea0f71bd 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -37,6 +37,7 @@
#include "smp.h"
#include "msft.h"
#include "eir.h"
+#include "aosp.h"

#define ZERO_KEY "\x00\x00\x00\x00\x00\x00\x00\x00" \
"\x00\x00\x00\x00\x00\x00\x00\x00"
@@ -4241,6 +4242,87 @@ static void hci_num_comp_blocks_evt(struct hci_dev *hdev, void *data,
queue_work(hdev->workqueue, &hdev->tx_work);
}

+/* Define the fixed vendor event prefixes below.
+ * Note: AOSP HCI Requirements use 0x54 and up as sub-event codes without
+ * actually defining a vendor prefix. Refer to
+ * https://source.android.com/devices/bluetooth/hci_requirements
+ * Hence, the other vendor event prefixes should not use the same
+ * space to avoid collision.
+ */
+static unsigned char AOSP_BQR_PREFIX[] = { 0x58 };
+
+/* Some vendor prefixes are fixed values and lengths. */
+#define FIXED_EVT_PREFIX(_prefix, _vendor_func) \
+{ \
+ .prefix = _prefix, \
+ .prefix_len = sizeof(_prefix), \
+ .vendor_func = _vendor_func, \
+ .get_prefix = NULL, \
+ .get_prefix_len = NULL, \
+}
+
+/* Some vendor prefixes are only available at run time. The
+ * values and lengths are variable.
+ */
+#define DYNAMIC_EVT_PREFIX(_prefix_func, _prefix_len_func, _vendor_func)\
+{ \
+ .prefix = NULL, \
+ .prefix_len = 0, \
+ .vendor_func = _vendor_func, \
+ .get_prefix = _prefix_func, \
+ .get_prefix_len = _prefix_len_func, \
+}
+
+/* Every distinct vendor specification must have a well-defined vendor
+ * event prefix to determine if a vendor event meets the specification.
+ * If an event prefix is fixed, it should be delcared with FIXED_EVT_PREFIX.
+ * Otherwise, DYNAMIC_EVT_PREFIX should be used for variable prefixes.
+ */
+struct vendor_event_prefix {
+ __u8 *prefix;
+ __u8 prefix_len;
+ void (*vendor_func)(struct hci_dev *hdev, void *data,
+ struct sk_buff *skb);
+ __u8 *(*get_prefix)(struct hci_dev *hdev);
+ __u8 (*get_prefix_len)(struct hci_dev *hdev);
+} evt_prefixes[] = {
+ FIXED_EVT_PREFIX(AOSP_BQR_PREFIX, aosp_quality_report_evt),
+ DYNAMIC_EVT_PREFIX(get_msft_evt_prefix, get_msft_evt_prefix_len,
+ msft_vendor_evt),
+
+ /* end with a null entry */
+ {},
+};
+
+static void hci_vendor_evt(struct hci_dev *hdev, void *data,
+ struct sk_buff *skb)
+{
+ int i;
+ __u8 *prefix;
+ __u8 prefix_len;
+
+ for (i = 0; evt_prefixes[i].vendor_func; i++) {
+ if (evt_prefixes[i].get_prefix)
+ prefix = evt_prefixes[i].get_prefix(hdev);
+ else
+ prefix = evt_prefixes[i].prefix;
+
+ if (evt_prefixes[i].get_prefix_len)
+ prefix_len = evt_prefixes[i].get_prefix_len(hdev);
+ else
+ prefix_len = evt_prefixes[i].prefix_len;
+
+ if (!prefix || prefix_len == 0)
+ continue;
+
+ /* Compare the raw prefix data directly. */
+ if (!memcmp(prefix, skb->data, prefix_len)) {
+ evt_prefixes[i].vendor_func(hdev, data, skb);
+ break;
+ }
+ }
+}
+
static void hci_mode_change_evt(struct hci_dev *hdev, void *data,
struct sk_buff *skb)
{
@@ -6844,7 +6926,7 @@ static const struct hci_ev {
HCI_EV(HCI_EV_NUM_COMP_BLOCKS, hci_num_comp_blocks_evt,
sizeof(struct hci_ev_num_comp_blocks)),
/* [0xff = HCI_EV_VENDOR] */
- HCI_EV_VL(HCI_EV_VENDOR, msft_vendor_evt, 0, HCI_MAX_EVENT_SIZE),
+ HCI_EV_VL(HCI_EV_VENDOR, hci_vendor_evt, 0, HCI_MAX_EVENT_SIZE),
};

static void hci_event_func(struct hci_dev *hdev, u8 event, struct sk_buff *skb,
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 08d6494f1b34..cab79f480a21 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -4389,6 +4389,26 @@ static int set_exp_feature(struct sock *sk, struct hci_dev *hdev,
MGMT_STATUS_NOT_SUPPORTED);
}

+int mgmt_quality_report(struct hci_dev *hdev, void *data, u32 data_len,
+ u8 quality_spec)
+{
+ struct mgmt_ev_quality_report *ev;
+ struct sk_buff *skb;
+
+ skb = mgmt_alloc_skb(hdev, MGMT_EV_QUALITY_REPORT,
+ sizeof(*ev) + data_len);
+ if (!skb)
+ return -ENOMEM;
+
+ ev = skb_put(skb, sizeof(*ev));
+ ev->quality_spec = quality_spec;
+ ev->data_len = data_len;
+ skb_put_data(skb, data, data_len);
+
+ return mgmt_event_skb(skb, NULL);
+}
+EXPORT_SYMBOL(mgmt_quality_report);
+
static int get_device_flags(struct sock *sk, struct hci_dev *hdev, void *data,
u16 data_len)
{
diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
index 9a3d77d3ca86..3edf64baf479 100644
--- a/net/bluetooth/msft.c
+++ b/net/bluetooth/msft.c
@@ -731,6 +731,20 @@ static void msft_monitor_device_evt(struct hci_dev *hdev, struct sk_buff *skb)
handle_data->mgmt_handle);
}

+__u8 *get_msft_evt_prefix(struct hci_dev *hdev)
+{
+ struct msft_data *msft = hdev->msft_data;
+
+ return msft->evt_prefix;
+}
+
+__u8 get_msft_evt_prefix_len(struct hci_dev *hdev)
+{
+ struct msft_data *msft = hdev->msft_data;
+
+ return msft->evt_prefix_len;
+}
+
void msft_vendor_evt(struct hci_dev *hdev, void *data, struct sk_buff *skb)
{
struct msft_data *msft = hdev->msft_data;
diff --git a/net/bluetooth/msft.h b/net/bluetooth/msft.h
index afcaf7d3b1cb..a354ebf61fed 100644
--- a/net/bluetooth/msft.h
+++ b/net/bluetooth/msft.h
@@ -27,6 +27,8 @@ int msft_set_filter_enable(struct hci_dev *hdev, bool enable);
int msft_suspend_sync(struct hci_dev *hdev);
int msft_resume_sync(struct hci_dev *hdev);
bool msft_curve_validity(struct hci_dev *hdev);
+__u8 *get_msft_evt_prefix(struct hci_dev *hdev);
+__u8 get_msft_evt_prefix_len(struct hci_dev *hdev);

#else

@@ -77,4 +79,14 @@ static inline bool msft_curve_validity(struct hci_dev *hdev)
return false;
}

+static inline __u8 *get_msft_evt_prefix(struct hci_dev *hdev)
+{
+ return NULL;
+}
+
+static inline __u8 get_msft_evt_prefix_len(struct hci_dev *hdev)
+{
+ return 0;
+}
+
#endif
--
2.35.0.263.gb82422642f-goog