USB scanner permission

[John Thompson]

After one of the latest rounds of updates of FC8 I find I can no longer 
use xsane as a normal user: it shows the "Looking for devices" pop-up 
but never finds my USB scanner. If I run xsane as "root" it works fine, 
so apparently this is a permission problem.

How do I determine which device file in /dev is being used for the 
scanner? This used to be simple before the days of udev...

[Mikkel]

John Thompson wrote:
> After one of the latest rounds of updates of FC8 I find I can no longer 
> use xsane as a normal user: it shows the "Looking for devices" pop-up 
> but never finds my USB scanner. If I run xsane as "root" it works fine, 
> so apparently this is a permission problem.
>
> How do I determine which device file in /dev is being used for the 
> scanner? This used to be simple before the days of udev...

This should be handled by a combination of 
/etc/udev/rules.d/60-libsane.rules and 
/etc/security/console.perms.d//etc/security/console.perms.d

I can not really test it here, as I am using a network scanner, and 
that is working.

Mikkel

[Andrea Mastellone]

Mikkel L. Ellertson wrote:
> John Thompson wrote:
> > After one of the latest rounds of updates of FC8 I find I can no 
> > longer use xsane as a normal user: it shows the "Looking for devices" 
> > pop-up but never finds my USB scanner. If I run xsane as "root" it 
> > works fine, so apparently this is a permission problem.
> >
> > How do I determine which device file in /dev is being used for the 
> > scanner? This used to be simple before the days of udev...
>
> This should be handled by a combination of 
> /etc/udev/rules.d/60-libsane.rules and 
> /etc/security/console.perms.d//etc/security/console.perms.d
>
> I can not really test it here, as I am using a network scanner, and that 
> is working.
>
> Mikkel

Simple trick (but not definitive):

As root, find your device and bus id by lsusb. Then, cd to

/dev/bus/usb/xxx/

(xxx being the bus id)

and chmod o+rw the device id.

AndreArtu

[John Thompson]

On 2008-02-20, Andrea Mastellone  wrote:
> Mikkel L. Ellertson wrote:
> Simple trick (but not definitive):
>
> As root, find your device and bus id by lsusb. Then, cd to

Bus 001 Device 006: ID 04b8:0101 Seiko Epson Corp. Perfection 636
> /dev/bus/usb/xxx/
>
> (xxx being the bus id)
>
> and chmod o+rw the device id.

[root@lancre ~]# ls -l /dev/bus/usb/001/006
crw-rw-rw- 1 root users 189, 5 Feb 20 16:26 /dev/bus/usb/001/006

Still no joy. :-(

[Andrea Mastellone]

John Thompson wrote:
> On 2008-02-20, Andrea Mastellone  wrote:
> > Mikkel L. Ellertson wrote:
> > Simple trick (but not definitive):
> >
> > As root, find your device and bus id by lsusb. Then, cd to
>
> Bus 001 Device 006: ID 04b8:0101 Seiko Epson Corp. Perfection 636
> > /dev/bus/usb/xxx/
> >
> > (xxx being the bus id)
> >
> > and chmod o+rw the device id.
>
> [root@lancre ~]# ls -l /dev/bus/usb/001/006
> crw-rw-rw- 1 root users 189, 5 Feb 20 16:26 /dev/bus/usb/001/006
>
> Still no joy. :-(

I am sorry... on my system this trick works perfectly. Perhaps you have 
to tune udev setting at this point, but I do not know how to help you :|

Andrea

[John Thompson]

On 2008-02-20, Mikkel L. Ellertson  wrote:
> John Thompson wrote:
> > After one of the latest rounds of updates of FC8 I find I can no longer
> > use xsane as a normal user: it shows the "Looking for devices" pop-up
> > but never finds my USB scanner. If I run xsane as "root" it works fine,
> > so apparently this is a permission problem.
> >
> > How do I determine which device file in /dev is being used for the
> > scanner? This used to be simple before the days of udev...
> This should be handled by a combination 
> /etc/udev/rules.d/60-libsane.rules and
> /etc/security/console.perms.d/

I thought you might be onto something when I saw:

<console>  0660 <scanner>    0600 root.lp

But after changing it to:

<console>  0666 <scanner>    0666 root.users

It still didn't work.

Here's my scanner in /etc/udev/rules.d/60-libsane.rules:

# EPSON GT-7000U | EPSON Perfection 636U | Epson Perfection 636U
ATTR{idVendor}=="04b8", ATTR{idProduct}=="0101", SYMLINK+="scanner-%k"

I suspect I just don't know what I'm doing here.

[Mikkel]

John Thompson wrote:
> I thought you might be onto something when I saw:
>
> <console>  0660 <scanner>    0600 root.lp
>
> But after changing it to:
>
> <console>  0666 <scanner>    0666 root.users
>
> It still didn't work.
>
> Here's my scanner in /etc/udev/rules.d/60-libsane.rules:
>
> # EPSON GT-7000U | EPSON Perfection 636U | Epson Perfection 636U
> ATTR{idVendor}=="04b8", ATTR{idProduct}=="0101", SYMLINK+="scanner-%k"
>
> I suspect I just don't know what I'm doing here.

The first set of permissions are the permissions when the user is 
logged into the local console. The owner.group is changed to that of 
the user. The second permissions are the default permissions when 
no-one is logged in locally. The owner.group is what the device gets 
set to in that case.

One thing to keep in mind - the changes will not affect a scanner 
that is already plugged in, unless the user that "owns" the console 
logs out.

It isn't the clearest, but you may want to read the console.perms 
and pam_console man pages.

Mikkel