Turn off gnome auto screen-lock when connected to specific wireless networks

pam_auth_inhibit_lock

#!/bin/sh -e

# Turn off gnome auto screen-lock when connected to specific wireless networks

# USAGE
# Add the following to /etc/pam.d/gdm-password, just after pam_gnome_keyring.so in the auth block:
#   auth optional pam_exec.so quiet /usr/local/sbin/pam_auth_inhibit_lock

# Hat tip - md, http://blog.bofh.it/debian/id_444

WIRELESS_IFACE=wlan0
AUTH_ESSID=orchard
AUTH_USER=steve

# return the ESSID of this interface
current_essid() {
  /sbin/iwconfig $1 | sed -nre '/ESSID/s/.*ESSID:"([^"]+)".*/\1/p'
}

# automatically unlock only for these users
case "$PAM_USER" in
  "")         echo "This program must be run by pam_auth.so!"
              exit 1
              ;;

  $AUTH_USER) ;;

  *)          exit 1
              ;;
esac

CURRENT_ESSID=$(current_essid $WIRELESS_IFACE)

# automatically turn off auto screen-lock when connected to these networks,
# otherwise turn on auto screen-lock
case "$CURRENT_ESSID" in
  $AUTH_ESSID)
    su -c "DISPLAY=:0 gsettings set org.gnome.desktop.screensaver lock-enabled false" $AUTH_USER
    exit 1
    ;;
  *)
    su -c "DISPLAY=:0 gsettings set org.gnome.desktop.screensaver lock-enabled true" $AUTH_USER
    exit 1
    ;;
esac

exit 6