PF suddenly malfunctioned

[Damien Fleuriot]

On 23 Jul 2012, at 01:49, jmattax at clanspum.net wrote:

> A few weeks ago (I've been trying to debug it myself since then) my pf
> firewall stopped working fully correctly. The symptom is that I can no longer
> access a variety of websites when I'm behind the firewall. I have verified
> that I can access all of the affected websites from outside my firewall. I
> have since stripped down my firewall (and general home server) so that it is
> no longer running named, sshguard or any useful firewalling rules in an
> attempt to figure out was broken but have been unable to do so.
> 
> Attached are my current /etc/pf.conf and /etc/rc.conf, to ensure that these
> are the configurations being used as of my last test I restarted the system
> and am still getting the same behavior. This behavior started sometime around
> a storm at my house, but since the firewall can see the websites that the
> computers behind it can't I don't believe the hardware is an issue.
> 
> Also, some websites (like anything google hosts) are just fine.
> 
> The also, so people can see what my kernel thinks I've attach the output of a
> couple of commands below
> 
> [root@ ~]# pfctl -s rules
> No ALTQ support in kernel
> ALTQ related functions disabled
> pass in quick all flags S/SA keep state
> pass out quick all flags S/SA keep state
> [root@ ~]# pfctl -s nat
> No ALTQ support in kernel
> ALTQ related functions disabled
> nat on xl0 inet from 10.11.10.0/24 to any -> 192.168.0.200
> [root at stilgar ~]# ifconfig
> re0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
>        options=389b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_UCAST,WOL_MCAST,WOL_MAGIC>
>        ether 90:e6:ba:60:9a:33
>        inet 10.11.10.1 netmask 0xffffff00 broadcast 10.11.10.255
>        media: Ethernet autoselect (100baseTX <full-duplex>)
>        status: active
> xl0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
>        options=82009<RXCSUM,VLAN_MTU,WOL_MAGIC,LINKSTATE>
>        ether 00:01:03:d1:fa:90
>        inet 192.168.0.200 netmask 0xffffff00 broadcast 192.168.0.255
>        media: Ethernet autoselect (100baseTX
> <full-duplex,flowcontrol,rxpause,txpause>)
>        status: active
> plip0: flags=8810<POINTOPOINT,SIMPLEX,MULTICAST> metric 0 mtu 1500
> ipfw0: flags=8801<UP,SIMPLEX,MULTICAST> metric 0 mtu 65536
> lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
>        options=3<RXCSUM,TXCSUM>
>        inet6 fe80::1%lo0 prefixlen 64 scopeid 0x5
>        inet6 ::1 prefixlen 128
>        inet 127.0.0.1 netmask 0xff000000
>        nd6 options=3<PERFORMNUD,ACCEPT_RTADV>
> pflog0: flags=141<UP,RUNNING,PROMISC> metric 0 mtu 33152
> 
> I would be very appreciative of any suggestions anyone can offer.
> 
>     Jason Mattax
> 

1/ OS version ? We can't tell from the current info

2/ When the problem appears. Have you tried disabling PF ? (pfctl -d)
Does it help ?

3/ The websites wouldn't be using connection recycling per chance ? (linux)
We've had a lot of problems with Linux enabled hosts using recycling, having them turn it off solved the problems.
There was not a thing we found on our side to fix it.
Disabling scrubbing wouldn't help either.