Re: PF packets being blocked...why?

Hmm, have you enabled net.inet.ip.forwarding?

Timo

Steve Williams <steve@williamsitconsulting.com> writes:

> Hi,
>
> Packets from vether are going out NAT'd no problem. I have 100%
> Internet access on 192.168.123.0/24.
>
> From my understanding, the "pass out quick inet all flags S/SA" allow
> packets out and should create state for the connection for any ipv4
> packets on any interface.
>
> Subsequent packets (these seem to have the "P"ush flag set) should
> match the state and not get blocked.
>
> Hum... perhaps the states are expiring too fast?
>
> How do I find out if the state existed at the time that the packet was
> blocked?
>
> Thanks,
> Steve W.
>
>
> On 26/06/2017 12:09 PM, Ville Valkonen wrote:
>> Hello,
>>
>> a quick glance and it seems you aren't allowing vether traffic to pass.
>>
>> --
>> Regards,
>> Ville
>>
>> On Jun 26, 2017 8:19 PM, "Steve Williams"
>> <steve@williamsitconsulting.com
>> <mailto:steve@williamsitconsulting.com>> wrote:
>>
>> 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 <tel: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
>>
>>
>>