/usr/sbin/guest-account is in lightdm 1.2.1-0ubuntu1.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 | #!/bin/sh -e
# (C) 2008 Canonical Ltd.
# Author: Martin Pitt <martin.pitt@ubuntu.com>
# License: GPL v2 or later
# modified by David D Lowe and Thomas Detoux
#
# Setup user and temporary home directory for guest session.
# If this succeeds, this script needs to print the username as the last line to
# stdout.
add_account ()
{
HOME=`mktemp -td guest-XXXXXX`
USER=`echo $HOME | sed 's/\(.*\)guest/guest/'`
# if $USER already exists, it must be a locked system account with no existing
# home directory
if PWSTAT=`passwd -S "$USER"` 2>/dev/null; then
if [ "`echo \"$PWSTAT\" | cut -f2 -d\ `" != "L" ]; then
echo "User account $USER already exists and is not locked"
exit 1
fi
PWENT=`getent passwd "$USER"` || {
echo "getent passwd $USER failed"
exit 1
}
GUEST_UID=`echo "$PWENT" | cut -f3 -d:`
if [ "$GUEST_UID" -ge 500 ]; then
echo "Account $USER is not a system user"
exit 1
fi
HOME=`echo "$PWENT" | cut -f6 -d:`
if [ "$HOME" != / ] && [ "${HOME#/tmp}" = "$HOME" ] && [ -d "$HOME" ]; then
echo "Home directory of $USER already exists"
exit 1
fi
else
# does not exist, so create it
adduser --system --no-create-home --home / --gecos "Guest" --group --shell /bin/bash $USER || {
umount "$HOME"
rm -rf "$HOME"
exit 1
}
fi
# create temporary home directory
mount -t tmpfs -o mode=700 none "$HOME" || { rm -rf "$HOME"; exit 1; }
chown $USER:$USER "$HOME"
gs_skel=/etc/guest-session/skel/
if [ -d "$gs_skel" ] && [ -n "`find $gs_skel -type f`" ]; then
cp -rT $gs_skel "$HOME"
else
cp -rT /etc/skel/ "$HOME"
fi
chown -R $USER:$USER "$HOME"
usermod -d "$HOME" "$USER"
#
# setup session
#
# disable screensaver, to avoid locking guest out of itself (no password)
su $USER <<EOF
gconftool-2 --set --type bool /desktop/gnome/lockdown/disable_lock_screen True
EOF
# disable some services that are unnecessary for the guest session
mkdir --parents "$HOME"/.config/autostart
cd /etc/xdg/autostart/
services="jockey-gtk.desktop update-notifier.desktop user-dirs-update-gtk.desktop"
for service in $services
do
if [ -e /etc/xdg/autostart/"$service" ] ; then
cp "$service" "$HOME"/.config/autostart
echo "X-GNOME-Autostart-enabled=false" >> "$HOME"/.config/autostart/"$service"
fi
done
# Load restricted session
#dmrc='[Desktop]\nSession=guest-restricted'
#/bin/echo -e "$dmrc" > "$HOME"/.dmrc
chown -R $USER:$USER "$HOME"
# set possible local guest session preferences
if [ -f /etc/guest-session/prefs.sh ]; then
. /etc/guest-session/prefs.sh
fi
echo $USER
}
remove_account ()
{
USER=$1
PWENT=`getent passwd "$USER"` || {
echo "Error: invalid user $USER"
exit 1
}
UID=`echo "$PWENT" | cut -f3 -d:`
HOME=`echo "$PWENT" | cut -f6 -d:`
if [ "$UID" -ge 500 ]; then
echo "Error: user $USER is not a system user."
exit 1
fi
if [ "${HOME}" = "${HOME#/tmp/}" ]; then
echo "Error: home directory $HOME is not in /tmp/."
exit 1
fi
# kill all remaining processes
while ps h -u "$USER" >/dev/null; do
killall -9 -u "$USER" || true
sleep 0.2;
done
umount "$HOME" || umount -l "$HOME" || true
rm -rf "$HOME"
# remove leftovers in /tmp
find /tmp -mindepth 1 -maxdepth 1 -uid "$UID" -print0 | xargs -0 rm -rf || true
deluser --system "$USER"
}
case "$1" in
add)
add_account
;;
remove)
if [ -z $2 ] ; then
echo "Usage: $0 remove [account]"
exit 1
fi
remove_account $2
;;
*)
echo "Usage: $0 add|remove"
exit 1
esac
|