To allow (1) or deny (0) interfaces a mask or interface attributes could written.
For interfaces that belongs together use the mask for authorization.
As default each bit has the initial value of the default authorization bit.
Entry: /sys/bus/usb/devices/*-*:*.*/interface_authorized
Signed-off-by: Stefan Koch <skoch@xxxxxxx>
---
drivers/usb/core/sysfs.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 55 insertions(+)
diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c
index afa0799e..54e2e8e 100644
--- a/drivers/usb/core/sysfs.c
+++ b/drivers/usb/core/sysfs.c
@@ -995,6 +995,60 @@ static ssize_t supports_autosuspend_show(struct device *dev,
}
static DEVICE_ATTR_RO(supports_autosuspend);
+/*
+ * show authorization status of usb interface
+ * 1 is authorized, 0 is not authorized
+ */
+static ssize_t interface_authorized_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct usb_interface *intf = to_usb_interface(dev);
+
+ if (!intf)
+ return -ENODEV;
+
+ return sprintf(buf, "%u\n", intf->authorized);
+}
+
+/*
+ * authorize or deauthorize an usb interface
+ * 1 is to authorize, 0 is to deauthorize
+ */
+static ssize_t interface_authorized_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct usb_interface *intf = to_usb_interface(dev);
+ struct usb_device *usb_pdev = NULL;
+ int rc = 0;
+ unsigned val = 0;
+ unsigned intf_nr = 0;
+ u32 mask = 0;
+
+ if (!dev->parent || !intf || !intf->cur_altsetting)
+ return -ENODEV;
+
+ usb_pdev = to_usb_device(dev->parent);
+
+ if (!usb_pdev)
+ return -ENODEV;
+
+ mask = usb_pdev->mask;
+ intf_nr = intf->cur_altsetting->desc.bInterfaceNumber;
+
+ if (sscanf(buf, "%u\n", &val) != 1)
+ return -EINVAL;
+
+ if (val == 0)
+ mask &= ~(1 << intf_nr);
+ else if (val == 1)
+ mask |= (1 << intf_nr);
+
+ rc = usb_device_set_mask(dev->parent, mask);
+
+ return rc < 0 ? rc : count;
+}
+static DEVICE_ATTR_RW(interface_authorized);
+
static struct attribute *intf_attrs[] = {
&dev_attr_bInterfaceNumber.attr,
&dev_attr_bAlternateSetting.attr,
@@ -1004,6 +1058,7 @@ static struct attribute *intf_attrs[] = {
&dev_attr_bInterfaceProtocol.attr,
&dev_attr_modalias.attr,
&dev_attr_supports_autosuspend.attr,
+ &dev_attr_interface_authorized.attr,
NULL,
};
static struct attribute_group intf_attr_grp = {
--
2.1.4
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
