Re: pyserial.tools.list_port improvement for FreeBSD

On Tue, Oct 22, 2024 at 8:47 PM Poul-Henning Kamp <phk@phk.freebsd.dk> wrote:
>
> --------
> Tomek CEDRO writes:
>
> > On the "desc:" in place of ugen I would put "Silicon Labs CP2102N USB
> > to UART Bridge Controller" as the ugen is in the HWID/LOCATION or
> > there is a reason to put ugen there? :-)
>
> The strings from the USB descriptors are unfortunately not available
> from devinfo(8) and usbconfig(8) needs root-privs to reveal them.
>
> I vaguely recall that the strings are not in devinfo (aka: "newbus")
> due to valid security concerns about unsafe "strings" like these,
> but I cannot find any evidence of/from that ancient discussion just
> now.
>
> I do find it inconsistent, that usbconfig(8) cannot function in
> read-only mode for plain users, given that the information it would
> reveal is already available for all from dmesg, but this might not
> be policy but merely an sideeffect of the implementation.

Hmm, I am running usbconfig on non-root user in the operator group
with some devfs.rules tweak that enables operator group members to
have full access to usb devices with no suid and I can see these
strings :-) I did put a pkg-message when creating OpenOCD port and it
seems to work fine for a long time :-)

% whoami
cederom

% cat /etc/devfs.rules
[system=10]
add path 'usb/*' mode 0660 group operator

% grep ruleset /etc/rc.conf
devfs_system_ruleset="localrules"

% whereis usbconfig
usbconfig: /usr/sbin/usbconfig /usr/share/man/man8/usbconfig.8.gz
/usr/src/usr.sbin/usbconfig

% ls -al /usr/sbin/usbconfig
-r-xr-xr-x  1 root  wheel  29504  4 lip 20:31 /usr/sbin/usbconfig

% usbconfig
(..)
ugen0.7: <STMicroelectronics STM32 STLink> at usbus0, cfg=0 md=HOST
spd=FULL (12Mbps) pwr=ON (300mA)

% ls -al /dev/usb/0.7*
crw-rw----  1 root  operator  0x24a 22 paź 20:50 /dev/usb/0.7.0
crw-rw----  1 root  operator  0x24e 22 paź 20:50 /dev/usb/0.7.1
crw-rw----  1 root  operator  0x250 22 paź 20:50 /dev/usb/0.7.2
crw-rw----  1 root  operator  0x252 22 paź 20:50 /dev/usb/0.7.3
crw-rw----  1 root  operator  0x253 22 paź 20:50 /dev/usb/0.7.4
crw-rw----  1 root  operator  0x280 22 paź 20:50 /dev/usb/0.7.5

Can you please verify? Maybe when this string is not available you can
put ugen0.7 instead? :-)

Thank you :-)
Tomek

-- 
CeDeROM, SQ7MHZ, http://www.tomek.cedro.info