Hi,
New install of OpenBSD 6.1 on apu2. Love the little box.
I have em0 as the connection to the Internet and I bridged em1 and em2
together on 192.168.123.0.
I've been using OpenBSD since the 2.7 days, but have never run NAT so
this is my first foray into that world. I have followed the FAQ on
"building a router" almost vebatim. It's working fine, but I am seeing
some packets blocked with no effect on browsing behind the OpenBSD box.
My ruleset:
# pfctl -sr
match in all scrub (no-df random-id)
match out on egress inet from ! (egress:network) to any nat-to
(egress:0) round-robin
block drop log quick from <blocklist> to any
block drop log quick from <bad_hosts> to any
block drop log all
pass out quick inet all flags S/SA
pass in on vether0 inet all flags S/SA
pass in on em1 inet all flags S/SA
pass in on em2 inet all flags S/SA
pass in on egress inet proto tcp from any to (egress) port = 22 flags S/SA
pass in on egress inet proto tcp from any to (egress) port = 993 flags S/SA
pass in on egress inet proto tcp from any to (egress) port = 80 flags S/SA
pass in on egress inet proto tcp from any to (egress) port = 443 flags S/SA
# tcpdump -n -e -ttt -i pflog0 # from man pflog man page
Jun 26 09:45:54.241145 rule 4/(match) block in on vether0:
192.168.123.2.38022 > 216.58.216.165.443: P 0:1375(1375) ack 1 win 1805 (DF)
Jun 26 09:45:54.701283 rule 4/(match) block in on vether0:
192.168.123.2.38022 > 216.58.216.165.443: P 0:1375(1375) ack 1 win 1805 (DF)
Jun 26 09:45:55.623757 rule 4/(match) block in on vether0:
192.168.123.2.38022 > 216.58.216.165.443: P 0:1375(1375) ack 1 win 1805 (DF)
Jun 26 09:45:57.460985 rule 4/(match) block in on vether0:
192.168.123.2.38022 > 216.58.216.165.443: P 0:1375(1375) ack 1 win 1805 (DF)
Jun 26 09:46:01.150933 rule 4/(match) block in on vether0:
192.168.123.2.38022 > 216.58.216.165.443: P 0:1375(1375) ack 1 win 1805 (DF)
Jun 26 09:46:08.522599 rule 4/(match) block in on vether0:
192.168.123.2.38022 > 216.58.216.165.443: P 0:1375(1375) ack 1 win 1805 (DF)
Jun 26 09:46:47.479083 rule 4/(match) block in on vether0:
192.168.123.2.46549 > 172.217.3.206.443: P 4042174712:4042174735(23) ack
2564095917 win 1593 (DF)
Jun 26 09:46:47.896295 rule 4/(match) block in on vether0:
192.168.123.2.53452 > 23.23.126.54.443: P 4003838125:4003838156(31) ack
2044539346 win 65535 (DF)
Jun 26 09:46:47.896662 rule 4/(match) block in on vether0:
192.168.123.2.53452 > 23.23.126.54.443: R 31:31(0) ack 1 win 65535 (DF)
Jun 26 09:46:47.896674 rule 4/(match) block in on vether0:
192.168.123.2.59762 > 216.58.216.163.443: P 113176577:113176608(31) ack
2619790719 win 1403 (DF)
Jun 26 09:46:47.896685 rule 4/(match) block in on vether0:
192.168.123.2.59762 > 216.58.216.163.443: F 31:31(0) ack 1 win 1403 (DF)
Jun 26 09:46:47.896711 rule 4/(match) block in on vether0:
192.168.123.2.39279 > 31.13.77.6.443: P 4254697166:4254697197(31) ack
2615144509 win 1545 (DF)
Jun 26 09:46:47.896735 rule 4/(match) block in on vether0:
192.168.123.2.39279 > 31.13.77.6.443: R 31:31(0) ack 1 win 1545 (DF)
# pfctl -R 4 -sr
block drop log all
It is not all https traffice that is being blocked as I can hit my
banking site, etc. Does anyone have an idea why are these packets being
blocked?
Thanks,
Steve Williams
