fauxcon

A utility to provide a direct connection between your keyboard and the console of a system. Very handy if you're ssh'd into a system, but need to fake keystrokes on the physical console.

I use this (so far!) to operate my Raspberryy Pi's as if I had a keyboard hooked up, while logged in via ssh. Honest, you don't know how useful this is until you try it.

It uses uinput, so you'll have to have the module loaded:

sudo modprobe uinput

Should load it if necessary. My laptops (Jessie/Sid) and RPi Raspian (Jessie/Sid) systems all seem to have it loaded automatically. You may force loading of the uinput module by placing it's name in /etc/modules, or better, by placing it's name in a file within the /etc/modules-load.d subdirectory. Thusly:

/etc/modules-load.d/load-uinput.conf
    # load uinput module automatically at startup
    #
    uinput

Of course, the uinput system will have permissions set to require root access to create a fake keyboard/mouse device. Generally, you'll have to start fauxcon with sudo to use it:

sudo fauxcon

Another possibility, set the setuid bit on fauxcon:

sudo chown root:root fauxcon
sudo chmod 4755 fauxcon         # -or- u=rwxs,g=rx,o=rx

To run fauxcon as a normal user, udev rules to allow users in particular group can be added. Edit /etc/udev/rules.d/99-uinput.rules and insert the following:

KERNEL=="uinput", GROUP="uinput", MODE:="0660"

Create the uinput group, then add a user (pi in this example) to the group with the following commands:

sudo groupadd -f uinput
sudo gpasswd -a pi uinput

The new group membership take effect in new shell sessions. To make an existing session aware of the new group membership, type newgrp uinput.

The new udev rule will be active after reboot. To enable the new rule immediately, run these commands:

sudo udevadm control --reload
sudo udevadm trigger --type=devices --sysname-match=uinput

By default, to EXIT fauxcon, you'll need to type a specific 3 character sequence, since we're emulating a full keyboard, you need to be able to type anything and everything. I've chosen a sequence similar to SSH's escape character, defaulting to '%'. (Can't be the same, as I envision using this over ssh connections too.) You'll need to type <ENTER>, then the ESCAPE CHAR, then a period ('.'). Hopefully not too many '<CR>%.' sequences occur in the wild.

TODO: Mouse passthrough. Quirky, since I'd really have to grab and constrain the mouse locally, while transmitting all the motions and clicks. ('remote mode'? see below) Probably best to make mouse passthrough NOT enabled by default, since anyone trying out fauxcon without reading the man page would suddenly have no working mouse, making it considerably more difficult to frantically kill fauxcon to restore their keyboard. (Nah, that wouldn't happen, would it?)

TODO: Remote mode. Viability of a 'remote' connection method? Run fauxcon locally, it connects to another machine and passes keystrokes through. Perhaps like rsync does, essentially connecting to itself to do work. (would make constraining mouse easier, see 'mouse passthrough' TODO above)

lornix/fauxcon

fauxcon