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#
# pass ack packets (ie established connection)
#
pass in proto tcp from 10.1.0.0/16 port = 23 to 10.2.0.0/16 flags A/A
pass out proto tcp from 10.1.0.0/16 port = 23 to 10.2.0.0/16 flags A/A
#
# block incoming connection requests to my internal network from the big bad
# internet.
#
block in on le0 proto tcp from any to 10.1.0.0/16 flags S/SA
#  to block the replies:
block out on le0 proto tcp from 10.1.0.0 to any flags SA/SA