FreeBSD 7.0 and pf

[Norman Maurer]

Am Mittwoch, den 19.03.2008, 14:04 +0530 schrieb Girish Venkatachalam:
> On 07:56:48 Mar 19, Norman Maurer wrote:
> > Hi all,
> > 
> > im using freebsd 7.0  + gif interfaces + racoon + pf to filter stuff on
> > my box. After upgrading to freebsd 7.0 I see some strange behavior. I
> > see packets get dropped because of bad hdr length. The problems only
> > seems to happen on traffic between the local nets and nets routed via
> > ipsec. Here is a tcpdump snipped:
> > 
> > block in on em5: 192.168.175.4.1107 > 192.168.116.6.22:  tcp 544 [bad
> > hdr length 12 - too short, < 20]
> > 
> > gif interface:
> > gif5: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> metric 0 mtu 1402
> >         tunnel inet 213.157.17.67 --> 213.23.198.131
> >         inet 192.168.116.1 --> 192.168.175.1 netmask 0xffffff00 
> > 
> > 
> > Any help is welcome.
> 
> A TCP header can never be less than 20 bytes.
> 
> And 12 is odd since all headers are a multiple of 4 bytes (word
> boundary).
> 
> Check your MTU of the PPPoE/PPPoA/Ethernet/WiFi or whatever datalink
> layer. I bet there is a problem there.
> 
> Best,
> Girish
> 
Maybe the problem is the mtu of the gif interface ( 1402 ) ?
I have a 4 mbit broadband connection ( no dsl ).

bye
Norman