Anchor evaluation

[David DeSimone]

Manoj Ganesan <manoj.ganesan at gmail.com> wrote:
>
> I'm probably doing something very silly here, which I can't figure out. I'm
> trying to get an anchor to be evaluated, but I can't seem to get traffic to
> go through.
> 
> My /etc/pf.conf looks like:
> 
> rdr pass log on ix0 proto udp from 10.0.111.61 to any port 1234 ->
> 10.0.211.62 port 4321
> nat pass log on ix0 from 10.0.211.62 port 4321 to 10.0.111.61 ->
> 10.0.111.71 port 1234
> pass out all
> 
> I want to replace these by an anchor like so (my /etc/pf.conf looks like):
> 
> anchor my_anchor
> load anchor gamenode from "/usr/home/my_user/my_anchor"

You're telling PF to evaluate an anchor "my_anchor" but you named the
anchor "gamenode", so there are no rules to be evaluated in that case.


> where the /usr/home/my_user/my_anchor looks like:
> 
> rdr pass log on ix0 proto udp from 10.0.111.61 to any port 1234 ->
> 10.0.211.62 port 4321
> nat pass log on ix0 from 10.0.211.62 port 4321 to 10.0.111.61 ->
> 10.0.111.71 port 1234
> pass out all
> 
> But while the anchor-less case lets packets through, the anchor case
> doesn't. Am I doing something wrong here?

The "anchor" directive tells PF to only evaluate filter rules from the
anchor.  I would assume you also need "nat-anchor" and "rdr-anchor"
directives to force all of the anchor rules to be evaluated:

    nat-anchor my_anchor
    rdr-anchor my_anchor
        anchor my_anchor

    load anchor my_anchor from "/usr/home/my_user/my_anchor"

-- 
David DeSimone == Network Admin == fox at verio.net
  "I don't like spinach, and I'm glad I don't, because if I
   liked it I'd eat it, and I just hate it." -- Clarence Darrow


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