guest-account: Blindly copy Ubuntu's guest-account script from bin:package lightdm into this project.

1 files changed, 229 insertions, 0 deletions

diff --git a/arctica-guest-account-script b/arctica-guest-account-script
new file mode 100755
index 0000000..f618390
--- /dev/null
+++ b/arctica-guest-account-script
@@ -0,0 +1,229 @@
+#!/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.
+
+export TEXTDOMAINDIR=/usr/share/locale-langpack
+export TEXTDOMAIN=lightdm
+
+# set the system wide locale for gettext calls
+if [ -f /etc/default/locale ]; then
+  . /etc/default/locale
+  LANGUAGE=
+  export LANG LANGUAGE
+fi
+
+is_system_user ()
+{
+  UID_MIN=$(cat /etc/login.defs | grep UID_MIN | awk '{print $2}')
+  SYS_UID_MIN=$(cat /etc/login.defs | grep SYS_UID_MIN | awk '{print $2}')
+  SYS_UID_MAX=$(cat /etc/login.defs | grep SYS_UID_MAX | awk '{print $2}')
+
+  SYS_UID_MIN=${SYS_UID_MIN:-101}
+  SYS_UID_MAX=${SYS_UID_MAX:-$(( UID_MIN - 1 ))}
+
+  [ ${1} -ge ${SYS_UID_MIN} ] && [ ${1} -le ${SYS_UID_MAX} ]
+}
+
+add_account ()
+{
+  temp_home=$(mktemp -td guest-XXXXXX)
+  GUEST_HOME=$(echo ${temp_home} | tr '[:upper:]' '[:lower:]')
+  GUEST_USER=${GUEST_HOME#/tmp/}
+  if [ "${GUEST_HOME}" != "${temp_home}" ]; then
+    mkdir "${GUEST_HOME}" || {
+      echo "Failed to create ${GUEST_USER}'s home directory (${GUEST_HOME})"
+      exit 1
+    }
+    rmdir "${temp_home}"
+  fi
+
+  # if ${GUEST_USER} already exists, it must be a locked system account with no existing
+  # home directory
+  if PWSTAT=$(passwd -S ${GUEST_USER}) 2>/dev/null; then
+    if [ $(echo ${PWSTAT} | cut -f2 -d' ') != L ]; then
+      echo "User account ${GUEST_USER} already exists and is not locked"
+      exit 1
+    fi
+
+    PWENT=$(getent passwd ${GUEST_USER}) || {
+      echo "getent passwd ${GUEST_USER} failed"
+      exit 1
+    }
+
+    GUEST_UID=$(echo ${PWENT} | cut -f3 -d:)
+
+    if ! is_system_user ${GUEST_UID}; then
+      echo "Account ${GUEST_USER} is not a system user"
+      exit 1
+    fi
+
+    GUEST_HOME=$(echo ${PWENT} | cut -f6 -d:)
+
+    if [ ${GUEST_HOME} != / ] && [ ${GUEST_HOME#/tmp} = ${GUEST_HOME} ] && [ -d ${GUEST_HOME} ]; then
+      echo "Home directory of ${GUEST_USER} already exists"
+      exit 1
+    fi
+  else
+    # does not exist, so create it
+    useradd --system --home-dir ${GUEST_HOME} --comment $(gettext "Guest") --user-group --shell /bin/bash ${GUEST_USER} || {
+      rm -rf ${GUEST_HOME}
+      exit 1
+    }
+  fi
+
+  dist_gs=/usr/share/lightdm/guest-session
+  site_gs=/etc/guest-session
+
+  # create temporary home directory
+  mount -t tmpfs -o mode=700,uid=${GUEST_USER} none ${GUEST_HOME} || {
+    rm -rf ${GUEST_HOME}
+    exit 1
+  }
+
+  if [ -d ${site_gs}/skel ] && [ "$(ls -A ${site_gs}/skel)" ]; then
+    # Only perform union-mounting if BindFS is available
+    if [ -x /usr/bin/bindfs ]; then
+      bindfs_mount=true
+
+      # Try OverlayFS first
+      if modinfo -n overlay >/dev/null 2>&1; then
+        mkdir ${GUEST_HOME}/upper ${GUEST_HOME}/work
+        chown ${GUEST_USER}:${GUEST_USER} ${GUEST_HOME}/upper ${GUEST_HOME}/work
+
+        mount -t overlay -o lowerdir=${dist_gs}/skel:${site_gs}/skel,upperdir=${GUEST_HOME}/upper,workdir=${GUEST_HOME}/work overlay ${GUEST_HOME} || {
+          umount ${GUEST_HOME}
+          rm -rf ${GUEST_HOME}
+          exit 1
+        }
+      # If OverlayFS is not available, try AuFS
+      elif [ -x /sbin/mount.aufs ]; then
+        mount -t aufs -o br=${GUEST_HOME}:${dist_gs}/skel:${site_gs}/skel none ${GUEST_HOME} || {
+          umount ${GUEST_HOME}
+          rm -rf ${GUEST_HOME}
+          exit 1
+        }
+      # If none of them is available, fall back to copy over
+      else
+        cp -rT ${site_gs}/skel/ ${GUEST_HOME}
+        cp -rT ${dist_gs}/skel/ ${GUEST_HOME}
+        chown -R ${GUEST_USER}:${GUEST_USER} ${GUEST_HOME}
+        bindfs_mount=false
+      fi
+
+      if ${bindfs_mount}; then
+        # Wrap ${GUEST_HOME} in a BindFS mount, so that
+        # ${GUEST_USER} will be seen as the owner of ${GUEST_HOME}'s contents.
+        bindfs -u ${GUEST_USER} -g ${GUEST_USER} ${GUEST_HOME} ${GUEST_HOME} || {
+          umount ${GUEST_HOME} # union mount
+          umount ${GUEST_HOME} # tmpfs mount
+          rm -rf ${GUEST_HOME}
+          exit 1
+        }
+      fi
+    # If BindFS is not available, just fall back to copy over
+    else
+      cp -rT ${site_gs}/skel/ ${GUEST_HOME}
+      cp -rT ${dist_gs}/skel/ ${GUEST_HOME}
+      chown -R ${GUEST_USER}:${GUEST_USER} ${GUEST_HOME}
+    fi
+  else
+    cp -rT /etc/skel/ ${GUEST_HOME}
+    cp -rT ${dist_gs}/skel/ ${GUEST_HOME}
+    chown -R ${GUEST_USER}:${GUEST_USER} ${GUEST_HOME}
+  fi
+
+  # setup session
+  su ${GUEST_USER} -c "env HOME=${GUEST_HOME} site_gs=${site_gs} ${dist_gs}/setup.sh"
+
+  # set possible local guest session preferences
+  source_local_prefs() {
+    local USER=${GUEST_USER}
+    local HOME=${GUEST_HOME}
+    . ${site_gs}/prefs.sh
+    chown -R ${USER}:${USER} ${HOME}
+  }
+  if [ -f ${site_gs}/prefs.sh ]; then
+    source_local_prefs
+  fi
+
+  echo ${GUEST_USER}
+}
+
+remove_account ()
+{
+  GUEST_USER=${1}
+
+  PWENT=$(getent passwd ${GUEST_USER}) || {
+    echo "Error: invalid user ${GUEST_USER}"
+    exit 1
+  }
+
+  GUEST_UID=$(echo ${PWENT} | cut -f3 -d:)
+
+  if ! is_system_user ${GUEST_UID}; then
+    echo "Error: user ${GUEST_USER} is not a system user."
+    exit 1
+  fi
+
+  GUEST_HOME=$(echo ${PWENT} | cut -f6 -d:)
+
+  # kill all remaining processes
+  if [ -x /bin/loginctl ] || [ -x /usr/bin/loginctl ]; then
+    loginctl --signal=9 kill-user ${GUEST_USER} >/dev/null || true
+  else
+    while ps h -u ${GUEST_USER} >/dev/null
+    do
+      killall -9 -u ${GUEST_USER} || true
+      sleep 0.2;
+    done
+  fi
+
+  if [ ${GUEST_HOME} = ${GUEST_HOME#/tmp/} ]; then
+    echo "Warning: home directory ${GUEST_HOME} is not in /tmp/. It won't be removed."
+  else
+    umount ${GUEST_HOME} || umount -l ${GUEST_HOME} || true # BindFS mount
+    umount ${GUEST_HOME} || umount -l ${GUEST_HOME} || true # union mount
+    umount ${GUEST_HOME} || umount -l ${GUEST_HOME} || true # tmpfs mount
+    rm -rf ${GUEST_HOME}
+  fi
+
+  # remove leftovers in /tmp
+  find /tmp -mindepth 1 -maxdepth 1 -uid ${GUEST_UID} -print0 | xargs -0 rm -rf || true
+
+  # remove possible {/run,}/media/guest-XXXXXX folder
+  for media_dir in /run/media/${GUEST_USER} /media/${GUEST_USER}; do
+    if [ -d ${media_dir} ]; then
+      for dir in $(find ${media_dir} -mindepth 1 -maxdepth 1); do
+        umount ${dir} || true
+      done
+
+      rmdir ${media_dir} || true
+    fi
+  done
+
+  userdel --force ${GUEST_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"
+    echo "       ${0} remove [account]"
+    exit 1
+esac