Bluetooth: mgmt: Implement support for passkey notification

This patch adds support for Secure Simple Pairing with devices that have
KeyboardOnly as their IO capability. Such devices will cause a passkey
notification on our side and optionally also keypress notifications.
Without this patch some keyboards cannot be paired using the mgmt
interface.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Cc: stable@vger.kernel.org
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>

5 files changed, 114 insertions, 0 deletions

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 0f28f7052f82..76b2b6bdcf36 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -1249,6 +1249,24 @@ struct hci_ev_simple_pair_complete {
         bdaddr_t bdaddr;
 } __packed;
 
+#define HCI_EV_USER_PASSKEY_NOTIFY      0x3b
+struct hci_ev_user_passkey_notify {
+        bdaddr_t        bdaddr;
+        __le32          passkey;
+} __packed;
+
+#define HCI_KEYPRESS_STARTED            0
+#define HCI_KEYPRESS_ENTERED            1
+#define HCI_KEYPRESS_ERASED             2
+#define HCI_KEYPRESS_CLEARED            3
+#define HCI_KEYPRESS_COMPLETED          4
+
+#define HCI_EV_KEYPRESS_NOTIFY          0x3c
+struct hci_ev_keypress_notify {
+        bdaddr_t        bdaddr;
+        __u8            type;
+} __packed;
+
 #define HCI_EV_REMOTE_HOST_FEATURES     0x3d
 struct hci_ev_remote_host_features {
         bdaddr_t bdaddr;
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 6a3337e9c42c..e7d454609881 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -303,6 +303,8 @@ struct hci_conn {
         __u8            pin_length;
         __u8            enc_key_size;
         __u8            io_capability;
+        __u32           passkey_notify;
+        __u8            passkey_entered;
         __u16           disc_timeout;
         unsigned long   flags;
 
@@ -1022,6 +1024,9 @@ int mgmt_user_passkey_reply_complete(struct hci_dev *hdev, bdaddr_t *bdaddr,
                                      u8 link_type, u8 addr_type, u8 status);
 int mgmt_user_passkey_neg_reply_complete(struct hci_dev *hdev, bdaddr_t *bdaddr,
                                          u8 link_type, u8 addr_type, u8 status);
+int mgmt_user_passkey_notify(struct hci_dev *hdev, bdaddr_t *bdaddr,
+                             u8 link_type, u8 addr_type, u32 passkey,
+                             u8 entered);
 int mgmt_auth_failed(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
                      u8 addr_type, u8 status);
 int mgmt_auth_enable_complete(struct hci_dev *hdev, u8 status);
diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
index 1b48effcd973..22980a7c3873 100644
--- a/include/net/bluetooth/mgmt.h
+++ b/include/net/bluetooth/mgmt.h
@@ -478,3 +478,10 @@ struct mgmt_ev_device_unblocked {
 struct mgmt_ev_device_unpaired {
         struct mgmt_addr_info addr;
 } __packed;
+
+#define MGMT_EV_PASSKEY_NOTIFY          0x0017
+struct mgmt_ev_passkey_notify {
+        struct mgmt_addr_info addr;
+        __le32  passkey;
+        __u8    entered;
+} __packed;
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 48d730228c2f..ccca88fc6195 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -3263,6 +3263,65 @@ static void hci_user_passkey_request_evt(struct hci_dev *hdev,
                 mgmt_user_passkey_request(hdev, &ev->bdaddr, ACL_LINK, 0);
 }
 
+static void hci_user_passkey_notify_evt(struct hci_dev *hdev,
+                                        struct sk_buff *skb)
+{
+        struct hci_ev_user_passkey_notify *ev = (void *) skb->data;
+        struct hci_conn *conn;
+
+        BT_DBG("%s", hdev->name);
+
+        conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &ev->bdaddr);
+        if (!conn)
+                return;
+
+        conn->passkey_notify = __le32_to_cpu(ev->passkey);
+        conn->passkey_entered = 0;
+
+        if (test_bit(HCI_MGMT, &hdev->dev_flags))
+                mgmt_user_passkey_notify(hdev, &conn->dst, conn->type,
+                                         conn->dst_type, conn->passkey_notify,
+                                         conn->passkey_entered);
+}
+
+static void hci_keypress_notify_evt(struct hci_dev *hdev, struct sk_buff *skb)
+{
+        struct hci_ev_keypress_notify *ev = (void *) skb->data;
+        struct hci_conn *conn;
+
+        BT_DBG("%s", hdev->name);
+
+        conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &ev->bdaddr);
+        if (!conn)
+                return;
+
+        switch (ev->type) {
+        case HCI_KEYPRESS_STARTED:
+                conn->passkey_entered = 0;
+                return;
+
+        case HCI_KEYPRESS_ENTERED:
+                conn->passkey_entered++;
+                break;
+
+        case HCI_KEYPRESS_ERASED:
+                conn->passkey_entered--;
+                break;
+
+        case HCI_KEYPRESS_CLEARED:
+                conn->passkey_entered = 0;
+                break;
+
+        case HCI_KEYPRESS_COMPLETED:
+                return;
+        }
+
+        if (test_bit(HCI_MGMT, &hdev->dev_flags))
+                mgmt_user_passkey_notify(hdev, &conn->dst, conn->type,
+                                         conn->dst_type, conn->passkey_notify,
+                                         conn->passkey_entered);
+}
+
 static void hci_simple_pair_complete_evt(struct hci_dev *hdev,
                                          struct sk_buff *skb)
 {
@@ -3627,6 +3686,14 @@ void hci_event_packet(struct hci_dev *hdev, struct sk_buff *skb)
                 hci_user_passkey_request_evt(hdev, skb);
                 break;
 
+        case HCI_EV_USER_PASSKEY_NOTIFY:
+                hci_user_passkey_notify_evt(hdev, skb);
+                break;
+
+        case HCI_EV_KEYPRESS_NOTIFY:
+                hci_keypress_notify_evt(hdev, skb);
+                break;
+
         case HCI_EV_SIMPLE_PAIR_COMPLETE:
                 hci_simple_pair_complete_evt(hdev, skb);
                 break;
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 05d4b83a0189..8e1ab59a9cef 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -99,6 +99,7 @@ static const u16 mgmt_events[] = {
         MGMT_EV_DEVICE_BLOCKED,
         MGMT_EV_DEVICE_UNBLOCKED,
         MGMT_EV_DEVICE_UNPAIRED,
+        MGMT_EV_PASSKEY_NOTIFY,
 };
 
 /*
@@ -3276,6 +3277,22 @@ int mgmt_user_passkey_neg_reply_complete(struct hci_dev *hdev, bdaddr_t *bdaddr,
                                           MGMT_OP_USER_PASSKEY_NEG_REPLY);
 }
 
+int mgmt_user_passkey_notify(struct hci_dev *hdev, bdaddr_t *bdaddr,
+                             u8 link_type, u8 addr_type, u32 passkey,
+                             u8 entered)
+{
+        struct mgmt_ev_passkey_notify ev;
+
+        BT_DBG("%s", hdev->name);
+
+        bacpy(&ev.addr.bdaddr, bdaddr);
+        ev.addr.type = link_to_bdaddr(link_type, addr_type);
+        ev.passkey = __cpu_to_le32(passkey);
+        ev.entered = entered;
+
+        return mgmt_event(MGMT_EV_PASSKEY_NOTIFY, hdev, &ev, sizeof(ev), NULL);
+}
+
 int mgmt_auth_failed(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
                      u8 addr_type, u8 status)
 {