Bluetooth: Add class of device control to the management interface

This patch adds the possibility for user space to fully control the
Class of Device value of local adapters. To control the service class
bits each UUID that's added comes with a service class "hint" which acts
as a mask of bits that the UUID needs to have enabled. The
set_service_cache management command is used to make sure we queue up
all UUID changes as user space initializes its drivers and then send a
single HCI_Write_Class_of_Device command when initialization is
complete.

Signed-off-by: Johan Hedberg <[email protected]>
Signed-off-by: Gustavo F. Padovan <[email protected]>

Author: Johan Hedberg

include/net/bluetooth/hci.h

@@ -81,6 +81,7 @@ enum {
 	HCI_AUTO_OFF,
 	HCI_MGMT,
 	HCI_PAIRABLE,
+	HCI_SERVICE_CACHE,
 };
 
 /* HCI ioctl defines */

include/net/bluetooth/hci_core.h

@@ -70,6 +70,7 @@ struct bdaddr_list {
 struct bt_uuid {
 	struct list_head list;
 	u8 uuid[16];
+	u8 svc_hint;
 };
 
 #define NUM_REASSEMBLY 4
@@ -86,6 +87,8 @@ struct hci_dev {
 	bdaddr_t	bdaddr;
 	__u8		dev_name[248];
 	__u8		dev_class[3];
+	__u8		major_class;
+	__u8		minor_class;
 	__u8		features[8];
 	__u8		commands[64];
 	__u8		ssp_mode;

include/net/bluetooth/mgmt.h

@@ -76,6 +76,7 @@ struct mgmt_mode {
 struct mgmt_cp_add_uuid {
 	__le16 index;
 	__u8 uuid[16];
+	__u8 svc_hint;
 } __packed;
 
 #define MGMT_OP_REMOVE_UUID		0x000A
@@ -84,6 +85,19 @@ struct mgmt_cp_remove_uuid {
 	__u8 uuid[16];
 } __packed;
 
+#define MGMT_OP_SET_DEV_CLASS		0x000B
+struct mgmt_cp_set_dev_class {
+	__le16 index;
+	__u8 major;
+	__u8 minor;
+} __packed;
+
+#define MGMT_OP_SET_SERVICE_CACHE	0x000C
+struct mgmt_cp_set_service_cache {
+	__le16 index;
+	__u8 enable;
+} __packed;
+
 #define MGMT_EV_CMD_COMPLETE		0x0001
 struct mgmt_ev_cmd_complete {
 	__le16 opcode;

net/bluetooth/mgmt.c

@@ -571,7 +571,7 @@ static int set_pairable(struct sock *sk, unsigned char *data, u16 len)
 	return err;
 }
 
-static int uuid_rsp(struct sock *sk, u16 opcode, u16 index)
+static int index_rsp(struct sock *sk, u16 opcode, u16 index)
 {
 	struct mgmt_hdr *hdr;
 	struct mgmt_ev_cmd_complete *ev;
@@ -596,6 +596,39 @@ static int uuid_rsp(struct sock *sk, u16 opcode, u16 index)
 	return 0;
 }
 
+static u8 get_service_classes(struct hci_dev *hdev)
+{
+	struct list_head *p;
+	u8 val = 0;
+
+	list_for_each(p, &hdev->uuids) {
+		struct bt_uuid *uuid = list_entry(p, struct bt_uuid, list);
+
+		val |= uuid->svc_hint;
+	}
+
+	return val;
+}
+
+static int update_class(struct hci_dev *hdev)
+{
+	u8 cod[3];
+
+	BT_DBG("%s", hdev->name);
+
+	if (test_bit(HCI_SERVICE_CACHE, &hdev->flags))
+		return 0;
+
+	cod[0] = hdev->minor_class;
+	cod[1] = hdev->major_class;
+	cod[2] = get_service_classes(hdev);
+
+	if (memcmp(cod, hdev->dev_class, 3) == 0)
+		return 0;
+
+	return hci_send_cmd(hdev, HCI_OP_WRITE_CLASS_OF_DEV, sizeof(cod), cod);
+}
+
 static int add_uuid(struct sock *sk, unsigned char *data, u16 len)
 {
 	struct mgmt_cp_add_uuid *cp;
@@ -622,10 +655,15 @@ static int add_uuid(struct sock *sk, unsigned char *data, u16 len)
 	}
 
 	memcpy(uuid->uuid, cp->uuid, 16);
+	uuid->svc_hint = cp->svc_hint;
 
 	list_add(&uuid->list, &hdev->uuids);
 
-	err = uuid_rsp(sk, MGMT_OP_ADD_UUID, dev_id);
+	err = update_class(hdev);
+	if (err < 0)
+		goto failed;
+
+	err = index_rsp(sk, MGMT_OP_ADD_UUID, dev_id);
 
 failed:
 	hci_dev_unlock_bh(hdev);
@@ -676,7 +714,11 @@ static int remove_uuid(struct sock *sk, unsigned char *data, u16 len)
 		goto unlock;
 	}
 
-	err = uuid_rsp(sk, MGMT_OP_REMOVE_UUID, dev_id);
+	err = update_class(hdev);
+	if (err < 0)
+		goto unlock;
+
+	err = index_rsp(sk, MGMT_OP_REMOVE_UUID, dev_id);
 
 unlock:
 	hci_dev_unlock_bh(hdev);
@@ -685,6 +727,73 @@ static int remove_uuid(struct sock *sk, unsigned char *data, u16 len)
 	return err;
 }
 
+static int set_dev_class(struct sock *sk, unsigned char *data, u16 len)
+{
+	struct hci_dev *hdev;
+	struct mgmt_cp_set_dev_class *cp;
+	u16 dev_id;
+	int err;
+
+	cp = (void *) data;
+	dev_id = get_unaligned_le16(&cp->index);
+
+	BT_DBG("request for hci%u", dev_id);
+
+	hdev = hci_dev_get(dev_id);
+	if (!hdev)
+		return cmd_status(sk, MGMT_OP_SET_DEV_CLASS, ENODEV);
+
+	hci_dev_lock_bh(hdev);
+
+	hdev->major_class = cp->major;
+	hdev->minor_class = cp->minor;
+
+	err = update_class(hdev);
+
+	if (err == 0)
+		err = index_rsp(sk, MGMT_OP_SET_DEV_CLASS, dev_id);
+
+	hci_dev_unlock_bh(hdev);
+	hci_dev_put(hdev);
+
+	return err;
+}
+
+static int set_service_cache(struct sock *sk, unsigned char *data, u16 len)
+{
+	struct hci_dev *hdev;
+	struct mgmt_cp_set_service_cache *cp;
+	u16 dev_id;
+	int err;
+
+	cp = (void *) data;
+	dev_id = get_unaligned_le16(&cp->index);
+
+	hdev = hci_dev_get(dev_id);
+	if (!hdev)
+		return cmd_status(sk, MGMT_OP_SET_SERVICE_CACHE, ENODEV);
+
+	hci_dev_lock_bh(hdev);
+
+	BT_DBG("hci%u enable %d", dev_id, cp->enable);
+
+	if (cp->enable) {
+		set_bit(HCI_SERVICE_CACHE, &hdev->flags);
+		err = 0;
+	} else {
+		clear_bit(HCI_SERVICE_CACHE, &hdev->flags);
+		err = update_class(hdev);
+	}
+
+	if (err == 0)
+		err = index_rsp(sk, MGMT_OP_SET_SERVICE_CACHE, dev_id);
+
+	hci_dev_unlock_bh(hdev);
+	hci_dev_put(hdev);
+
+	return err;
+}
+
 int mgmt_control(struct sock *sk, struct msghdr *msg, size_t msglen)
 {
 	unsigned char *buf;
@@ -743,6 +852,12 @@ int mgmt_control(struct sock *sk, struct msghdr *msg, size_t msglen)
 	case MGMT_OP_REMOVE_UUID:
 		err = remove_uuid(sk, buf + sizeof(*hdr), len);
 		break;
+	case MGMT_OP_SET_DEV_CLASS:
+		err = set_dev_class(sk, buf + sizeof(*hdr), len);
+		break;
+	case MGMT_OP_SET_SERVICE_CACHE:
+		err = set_service_cache(sk, buf + sizeof(*hdr), len);
+		break;
 	default:
 		BT_DBG("Unknown op %u", opcode);
 		err = cmd_status(sk, opcode, 0x01);