[sane-devel] USB kernel scanner driver

[Sergey Vlasov]

On Wed, 23 Oct 2002 17:47:18 +0100
Major A <andras at users.sourceforge.net> wrote:

> How does libusb handle permissions on linux then? /proc/bus/usb can
> only be accessed by root. With the USB scanner module, one had a way
> of setting permissions via the device file.

Giving access to all USB devices is relatively simple: usbdevfs has
several mount options to control it: devuid, devgid, devmode; bus*,
list*.

> How would one restrict access so that although a user can scan, they
> can't fiddle with the USB hard drive or CD-ROM or automatic
> nuclear-weapon detonator?

This is trickier. Looks like the hotplug scripts are able to do this,
however, this needs some tweaks...

> saned is great at this, but it would now have as root (I tend to run
> it as a dedicated "saned" user), and I don't think we should lay the
> burden of setting saned up on the normal user who just wants to scan.

You can give the "saned" user the right to access all USB devices.