Am Mi, Mär 05, 2025 am 08:30:44 -0000 schrieb Grant Edwards:
I'm working on an application that allows you to remap/mix/reconfigure
the channels/buttons on a USB joystick/game-controller device. That
requires access to /dev/uinput which is used to create a "synthetic"
joystick device and feed data to it.
On Gentoo /dev/uinput is accessible only to root.
$ ls -l /dev/uinput
crw------- 1 root root 10, 223 Mar 5 09:36 /dev/uinput
What's the best way to make that available to specific users?
Add a "uinput" group, change the group of /dev/uinput to "uinput",
chmod g+wr, then make specific users part of that group?
That’s a way to do that, probably the easiest. If you go that way, you might
want to write that as part of your device manager rules, probably udev.
I’ve noticed recently on a Debian system, that /dev/hidraw* devices were
root:root 0600, but the one for my yubikey had an acl on it that gave my user
write access. This acl was set by elogind at login time (the idea being that
only the user behind the screen should be able to read from that device at any
time).
That could be another way to do that, although in your case the security
implications are probably not the same as for sensitive devices like yubikeys
and as such may not require such a setup.
