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On Tue, 12 Jul 2011 14:12:49 +0100 Kevin Lucas wrote: > Just been reading the LinuxUser mag and tried this from Joanna > Rutkowska It shows how insecure a root shell can be > > in a terminal > do > > ( you need the package "xorg-x11-apps" to do this) > > [kevin@kevinspc ~]$ xinput list > â Virtual core pointer id=2 [master > pointer (3)] â â Virtual core XTEST pointer > id=4 [slave pointer (2)] > â â Microsoft Microsoft Wireless Optical Mouse 1.0A > id=9 [slave pointer (2)] > â Virtual core keyboard id=3 [master > keyboard (2)] â Virtual core XTEST keyboard > id=5 [slave keyboard (3)] > â Power Button id=6 > [slave keyboard (3)] > â Power Button id=7 > [slave keyboard (3)] > â ov519 id=8 > [slave keyboard (3)] > â AT Translated Set 2 keyboard id=10 > [slave keyboard (3)] > â i2c IR (HVR 1110) id=11 > [slave keyboard (3)] > > > > note the AT id = 8 > type in > > xinput --test 8 > > then in a root terminal type some commands > > and see the keyboard codes as root types > remember you are just a normal user ? > > perhaps in a bash script you could redirect the output of xinput to > Dev/null or just Never install the Xorg-X11-apps Not a good situation to be in, but not one I imagine that will cause that many problems in current systems. Either that or I'm being short-sighted about this. It would seem that "xinput --test xx" will only show the input for the current X session. My keyboard shows up as id 11. I just tried running "xinput --test 11" in one window, opened another Gnome Terminal window and sure enough, the xinput test picked up the keypresses from the new terminal window, including after I had sudo su'd. Not good... but... I then tried running "xinput --test 11", swapped to another virtual terminal (CTRL+ALT+F1), logged in, ran a few commands and swapped back to the X session... none of the keypresses from the "other" session were picked up. Not surprising as the "other" session didn't involve X. So, in the "other" virtual terminal I opened up an X session with "startx -- :1"... opened a terminal in my second X session, typed a few commands, etc, swapped back to my main X session to check whether anything had been picked up by the running instance of "xinput --test 11"... nothing. So it would seem that yes, it will pick up all keypresses from the current X session, but it won't pick up keypresses from the hardware directly (or it would have picked up something from the command-line virual terminal session), and it won't pick up keypresses from other X sessions on the same machine (which might have been a problem in situations where you have 1 box running 2+ X sessions... think "Internet Cafe"). I can see some potential situations where this would be a potential problem, but then to my mind those situations would only arise if the system has been poorly setup anyway. Grant. -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/listfaq