HP-UX IPFilter Version A.03.05.14 Administrator's Guide

HP-UX IPFilter Configuration Examples
tcpstate
Appendix A 171
tcpstate
#
# Only allow TCP packets in/out of lan0 if there is an outgoing
# connection setup somewhere, waiting for it.
#
pass out quick on lan0 proto tcp from any to any flags S/SAFR
keep state
block out on lan0 proto tcp all
block in on lan0 proto tcp all
#
# allow nameserver queries and replies to pass through, but no
# other UDP
#
pass out quick on lan0 proto udp from any to any port = 53
keep state
block out on lan0 proto udp all
block in on lan0 proto udp all