[systemd-devel] Is it possible to dynamically remove the "uaccess" tag?

[David Herrmann]

Hey

On Mon, Feb 15, 2016 at 2:26 PM, Lennart Poettering
<lennart at poettering.net> wrote:
> On Sun, 14.02.16 19:18, Manuel Reimer (Manuel.Spam at nurfuerspam.de) wrote:
>
>> Hello,
>>
>> I want to create a daemon which translates inputs, given by an game
>> controller (/dev/input/eventX). The default is, that the tag "uaccess" is
>> set there.
>>
>> As soon as my daemon runs, I don't want to use the original input device.
>> Other applications should not connect to the original device but to my
>> translated uinput device.
>>
>> Currently, the only way to do this seems to be to delete the device nodes,
>> which seems to be a bit harsh to me.
>>
>> Can someone suggest an alternative way to get rid of what uaccess does as
>> long as my daemon is running and handling the device? As far as I can see
>> there is no way to remove tags with libudev. It also seems to be impossible
>> to set an ACL rule to deny access for everyone. Any other suggestions?
>
> There isn't any concept of ownership in udev, and I am pretty sure
> there shouln't be.
>
> input does know one however, in EVIOCGRAB.

..but you shouldn't use it. It is deprecated and it took us years to
get rid of it in the whole graphics stack.

Thanks
David