Bluetooth: LE advertising cache

This patch implements the LE advertising cache. It stores sensitive
information (bdaddr and bdaddr_type so far) gathered from LE
advertising report events.

Only advertising entries from connectables devices are added to the
cache.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 6c994c0..10dfb85 100644 (file)
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -89,6 +89,12 @@ struct oob_data {
        u8 randomizer[16];
 };
 
+struct adv_entry {
+       struct list_head list;
+       bdaddr_t bdaddr;
+       u8 bdaddr_type;
+};
+
 #define NUM_REASSEMBLY 4
 struct hci_dev {
        struct list_head list;
@@ -181,6 +187,8 @@ struct hci_dev {
 
        struct list_head        remote_oob_data;
 
+       struct list_head        adv_entries;
+
        struct hci_dev_stats    stat;
 
        struct sk_buff_head     driver_init;
@@ -527,6 +535,11 @@ int hci_add_remote_oob_data(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 *hash,
                                                                u8 *randomizer);
 int hci_remove_remote_oob_data(struct hci_dev *hdev, bdaddr_t *bdaddr);
 
+int hci_adv_entries_clear(struct hci_dev *hdev);
+struct adv_entry *hci_find_adv_entry(struct hci_dev *hdev, bdaddr_t *bdaddr);
+int hci_add_adv_entry(struct hci_dev *hdev,
+                                       struct hci_ev_le_advertising_info *ev);
+
 void hci_del_off_timer(struct hci_dev *hdev);
 
 void hci_event_packet(struct hci_dev *hdev, struct sk_buff *skb);

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 815269b..cc40f22 100644 (file)
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -1202,6 +1202,67 @@ int hci_add_remote_oob_data(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 *hash,
        return 0;
 }
 
+int hci_adv_entries_clear(struct hci_dev *hdev)
+{
+       struct adv_entry *entry, *tmp;
+
+       list_for_each_entry_safe(entry, tmp, &hdev->adv_entries, list) {
+               list_del(&entry->list);
+               kfree(entry);
+       }
+
+       BT_DBG("%s adv cache cleared", hdev->name);
+
+       return 0;
+}
+
+struct adv_entry *hci_find_adv_entry(struct hci_dev *hdev, bdaddr_t *bdaddr)
+{
+       struct adv_entry *entry;
+
+       list_for_each_entry(entry, &hdev->adv_entries, list)
+               if (bacmp(bdaddr, &entry->bdaddr) == 0)
+                       return entry;
+
+       return NULL;
+}
+
+static inline int is_connectable_adv(u8 evt_type)
+{
+       if (evt_type == ADV_IND || evt_type == ADV_DIRECT_IND)
+               return 1;
+
+       return 0;
+}
+
+int hci_add_adv_entry(struct hci_dev *hdev,
+                                       struct hci_ev_le_advertising_info *ev)
+{
+       struct adv_entry *entry;
+
+       if (!is_connectable_adv(ev->evt_type))
+               return -EINVAL;
+
+       /* Only new entries should be added to adv_entries. So, if
+        * bdaddr was found, don't add it. */
+       if (hci_find_adv_entry(hdev, &ev->bdaddr))
+               return 0;
+
+       entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
+       if (!entry)
+               return -ENOMEM;
+
+       bacpy(&entry->bdaddr, &ev->bdaddr);
+       entry->bdaddr_type = ev->bdaddr_type;
+
+       list_add(&entry->list, &hdev->adv_entries);
+
+       BT_DBG("%s adv entry added: address %s type %u", hdev->name,
+                               batostr(&entry->bdaddr), entry->bdaddr_type);
+
+       return 0;
+}
+
 /* Register HCI device */
 int hci_register_dev(struct hci_dev *hdev)
 {
@@ -1268,6 +1329,8 @@ int hci_register_dev(struct hci_dev *hdev)
 
        INIT_LIST_HEAD(&hdev->remote_oob_data);
 
+       INIT_LIST_HEAD(&hdev->adv_entries);
+
        INIT_WORK(&hdev->power_on, hci_power_on);
        INIT_WORK(&hdev->power_off, hci_power_off);
        setup_timer(&hdev->off_timer, hci_auto_off, (unsigned long) hdev);
@@ -1348,6 +1411,7 @@ int hci_unregister_dev(struct hci_dev *hdev)
        hci_uuids_clear(hdev);
        hci_link_keys_clear(hdev);
        hci_remote_oob_data_clear(hdev);
+       hci_adv_entries_clear(hdev);
        hci_dev_unlock_bh(hdev);
 
        __hci_dev_put(hdev);