@solene
cat /etc/pf.conf
# $OpenBSD: pf.conf,v 1.55 2017/12/03 20:40:04 sthen Exp $
#
# See pf.conf(5) and /etc/examples/pf.conf
set skip on lo
block return # block stateless traffic
pass # establish keep-state
# By default, do not permit remote connections to X11
block return in on ! lo0 proto tcp to port 6000:6010
# Port build user does not need network
block return out log proto {tcp udp} user _pbuild