Bluetooth: Move Service Discovery logic before refactoring

This patch moves whole packet filering logic of service discovery
into new function is_filter_match. It's done because logic inside
mgmt_device_found is very complicated and needs some
simplification.

Also having whole logic in one place will allow to simplify it in
the future.

Signed-off-by: Jakub Pawlowski <jpawlowski@google.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 1e4635a3374d00607bf6e3317289953f1ba108b5..a41a5efa4391a2da4a5c33744625d0057a9457f8 100644 (file)
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -7280,32 +7280,16 @@ static void restart_le_scan(struct hci_dev *hdev)
                           DISCOV_LE_RESTART_DELAY);
 }
 
-void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
-                      u8 addr_type, u8 *dev_class, s8 rssi, u32 flags,
-                      u8 *eir, u16 eir_len, u8 *scan_rsp, u8 scan_rsp_len)
+static bool is_filter_match(struct hci_dev *hdev, s8 rssi, u8 *eir,
+                           u16 eir_len, u8 *scan_rsp, u8 scan_rsp_len)
 {
-       char buf[512];
-       struct mgmt_ev_device_found *ev = (void *) buf;
-       size_t ev_size;
        bool match;
 
-       /* Don't send events for a non-kernel initiated discovery. With
-        * LE one exception is if we have pend_le_reports > 0 in which
-        * case we're doing passive scanning and want these events.
-        */
-       if (!hci_discovery_active(hdev)) {
-               if (link_type == ACL_LINK)
-                       return;
-               if (link_type == LE_LINK && list_empty(&hdev->pend_le_reports))
-                       return;
-       }
-
-       /* When using service discovery with a RSSI threshold, then check
-        * if such a RSSI threshold is specified. If a RSSI threshold has
-        * been specified, and HCI_QUIRK_STRICT_DUPLICATE_FILTER is not set,
-        * then all results with a RSSI smaller than the RSSI threshold will be
-        * dropped. If the quirk is set, let it through for further processing,
-        * as we might need to restart the scan.
+       /* If a RSSI threshold has been specified, and
+        * HCI_QUIRK_STRICT_DUPLICATE_FILTER is not set, then all results with
+        * a RSSI smaller than the RSSI threshold will be dropped. If the quirk
+        * is set, let it through for further processing, as we might need to
+        * restart the scan.
         *
         * For BR/EDR devices (pre 1.2) providing no RSSI during inquiry,
         * the results are also dropped.
@@ -7314,32 +7298,8 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
            (rssi == HCI_RSSI_INVALID ||
            (rssi < hdev->discovery.rssi &&
             !test_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks))))
-               return;
-
-       /* Make sure that the buffer is big enough. The 5 extra bytes
-        * are for the potential CoD field.
-        */
-       if (sizeof(*ev) + eir_len + scan_rsp_len + 5 > sizeof(buf))
-               return;
-
-       memset(buf, 0, sizeof(buf));
-
-       /* In case of device discovery with BR/EDR devices (pre 1.2), the
-        * RSSI value was reported as 0 when not available. This behavior
-        * is kept when using device discovery. This is required for full
-        * backwards compatibility with the API.
-        *
-        * However when using service discovery, the value 127 will be
-        * returned when the RSSI is not available.
-        */
-       if (rssi == HCI_RSSI_INVALID && !hdev->discovery.report_invalid_rssi &&
-           link_type == ACL_LINK)
-               rssi = 0;
+               return  false;
 
-       bacpy(&ev->addr.bdaddr, bdaddr);
-       ev->addr.type = link_to_bdaddr(link_type, addr_type);
-       ev->rssi = rssi;
-       ev->flags = cpu_to_le32(flags);
 
        if (eir_len > 0) {
                /* When using service discovery and a list of UUID is
@@ -7364,25 +7324,18 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
                }
 
                if (!match && !scan_rsp_len)
-                       return;
-
-               /* Copy EIR or advertising data into event */
-               memcpy(ev->eir, eir, eir_len);
+                       return  false;
        } else {
                /* When using service discovery and a list of UUID is
                 * provided, results with empty EIR or advertising data
                 * should be dropped since they do not match any UUID.
                 */
                if (hdev->discovery.uuid_count > 0 && !scan_rsp_len)
-                       return;
+                       return  false;
 
                match = false;
        }
 
-       if (dev_class && !eir_has_data_type(ev->eir, eir_len, EIR_CLASS_OF_DEV))
-               eir_len = eir_append_data(ev->eir, eir_len, EIR_CLASS_OF_DEV,
-                                         dev_class, 3);
-
        if (scan_rsp_len > 0) {
                /* When using service discovery and a list of UUID is
                 * provided, results with no matching UUID should be
@@ -7393,7 +7346,7 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
                        if (!match && !eir_has_uuids(scan_rsp, scan_rsp_len,
                                                     hdev->discovery.uuid_count,
                                                     hdev->discovery.uuids))
-                               return;
+                               return  false;
 
                        /* If duplicate filtering does not report RSSI changes,
                         * then restart scanning to ensure updated result with
@@ -7403,16 +7356,13 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
                                     &hdev->quirks))
                                restart_le_scan(hdev);
                }
-
-               /* Append scan response data to event */
-               memcpy(ev->eir + eir_len, scan_rsp, scan_rsp_len);
        } else {
                /* When using service discovery and a list of UUID is
                 * provided, results with empty scan response and no
                 * previous matched advertising data should be dropped.
                 */
                if (hdev->discovery.uuid_count > 0 && !match)
-                       return;
+                       return  false;
        }
 
        /* Validate the reported RSSI value against the RSSI threshold once more
@@ -7421,8 +7371,75 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
         */
        if (hdev->discovery.rssi != HCI_RSSI_INVALID &&
            rssi < hdev->discovery.rssi)
+               return  false;
+
+       return true;
+}
+
+void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
+                      u8 addr_type, u8 *dev_class, s8 rssi, u32 flags,
+                      u8 *eir, u16 eir_len, u8 *scan_rsp, u8 scan_rsp_len)
+{
+       char buf[512];
+       struct mgmt_ev_device_found *ev = (void *)buf;
+       size_t ev_size;
+
+       /* Don't send events for a non-kernel initiated discovery. With
+        * LE one exception is if we have pend_le_reports > 0 in which
+        * case we're doing passive scanning and want these events.
+        */
+       if (!hci_discovery_active(hdev)) {
+               if (link_type == ACL_LINK)
+                       return;
+               if (link_type == LE_LINK && list_empty(&hdev->pend_le_reports))
+                       return;
+       }
+
+       if (hdev->discovery.rssi != HCI_RSSI_INVALID ||
+           hdev->discovery.uuid_count > 0) {
+               /* We are using service discovery */
+               if (!is_filter_match(hdev, rssi, eir, eir_len, scan_rsp,
+                                    scan_rsp_len))
+                       return;
+       }
+
+       /* Make sure that the buffer is big enough. The 5 extra bytes
+        * are for the potential CoD field.
+        */
+       if (sizeof(*ev) + eir_len + scan_rsp_len + 5 > sizeof(buf))
                return;
 
+       memset(buf, 0, sizeof(buf));
+
+       /* In case of device discovery with BR/EDR devices (pre 1.2), the
+        * RSSI value was reported as 0 when not available. This behavior
+        * is kept when using device discovery. This is required for full
+        * backwards compatibility with the API.
+        *
+        * However when using service discovery, the value 127 will be
+        * returned when the RSSI is not available.
+        */
+       if (rssi == HCI_RSSI_INVALID && !hdev->discovery.report_invalid_rssi &&
+           link_type == ACL_LINK)
+               rssi = 0;
+
+       bacpy(&ev->addr.bdaddr, bdaddr);
+       ev->addr.type = link_to_bdaddr(link_type, addr_type);
+       ev->rssi = rssi;
+       ev->flags = cpu_to_le32(flags);
+
+       if (eir_len > 0)
+               /* Copy EIR or advertising data into event */
+               memcpy(ev->eir, eir, eir_len);
+
+       if (dev_class && !eir_has_data_type(ev->eir, eir_len, EIR_CLASS_OF_DEV))
+               eir_len = eir_append_data(ev->eir, eir_len, EIR_CLASS_OF_DEV,
+                                         dev_class, 3);
+
+       if (scan_rsp_len > 0)
+               /* Append scan response data to event */
+               memcpy(ev->eir + eir_len, scan_rsp, scan_rsp_len);
+
        ev->eir_len = cpu_to_le16(eir_len + scan_rsp_len);
        ev_size = sizeof(*ev) + eir_len + scan_rsp_len;