PF is blocking inbound/outbound ssh, nothing else

[Jeremy Chadwick]

On Tue, Sep 02, 2008 at 02:15:14PM -0700, Gavin Spomer wrote:
> I've recently had to leave my firewall off on my test server because when I'm ssh-ed in and enable pf, I get "locked out". :( It was working fine before and the only change that's happened recently is our university has a new ip range, but I've changed that in my config. I also have a production FreeBSD server of which I can ssh to (thankfully) with pf enabled and it's pf.conf is virtually the same.
> 
> My pf config relevant to this is: 
> 
>    #### LISTS/MACROS:
>    ext_if = "bce0"
> 
>    #### TABLES:
>    table <campusaccess> const { campus ip range omitted }
> 
>    #### OPTIONS:
>    set skip on lo0 
> 
>    #### NORMALIZATION:
>    scrub in all 
> 
>    #### FILTERING:
>    # default deny everything in and log 
>    block in log on $ext_if all 
>    block out log on $ext_if all 
> 
>    # activate spoofing
>    antispoof log quick for $ext_if inet
> 
>    # ssh for <campusaccess>
>    pass in on $ext_if proto tcp from <campusaccess> to $ext_if port 22 flags S/SA keep state
> 
>    (other rules for other services/ports that are working go here)
> 
>    # let stuff out
>    pass out on $ext_if proto { tcp, udp } from any to any keep state
> 
> /var/log/messages shows entries like:
> 
>    Sep  2 10:02:27 myserver sshd[21000]: fatal: Write failed: Operation not permitted
> 
> tcpdump -n -e -ttt -r /var/log/pflog shows entries like:
> 
>    32. 022410 rule 0/0(match): block in on bce0: mymacip.50186 > myserverip.22: P 1:97(96) ack 0 win 65535 <nop,nop,timestamp 32900581 4199243883>
> 
> and:
> 
>    2143. 098222 rule 1/0(match): block out on bce0: myserverip.22 > mymacip.50542: P 3200122721 :3200122817(96) ack 2819997173 win 8326 <nop,nop,timestamp 3729475032 32922638>
> 
> My Mac is within the <campusaccess> defined in my tables section. Only ssh is being blocked. Other things like port 80 for apache, port 3306 for MySQL, port 8080 for Plone, etc. are all fine.
> 
> I have searched the freebsd-pf list archives, but it only allows me one page of search results for some reason. I have also Googled a bit and have finally posted here. Very confused.

The version of FreeBSD you're using is important here.  What version?

-- 
| Jeremy Chadwick                                jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |