OSEC

Neohapsis is currently accepting applications for employment. For more information, please visit our website www.neohapsis.com or email hr@neohapsis.com
 
Subject: Re: recipient_delimiter in aliases
From: Nick Simicich (njsscifi.squawk.com)
Date: Wed Feb 02 2000 - 19:18:50 CST

At 08:39 AM 2/2/00 -0500, Wietse Venema wrote:
>By default, Postfix exempts owner-foo and foo-request from recipient
>delimiter processing. You can turn it on with:
>
> owner_request_special = no
>
>in the main.cf file.
>
>The reason for this brain damage is that '-' is often used as the
>delimiter (e.g., it's default with qmail) and that would conflict
>with owner-foo and foo-request.
>
>I wasn't going to make owner_request_special dependent on whether
>the delimiter is '-' or something else.
>
> Wietse

Thank you, this was the missing piece. I'm sorry to have bothered you
with something as trivial as this.

I'm not sure how to stop someone else from falling into the same trap. The
parameter owner_request_special was documented as giving these addresses
special treatment, but the treatment was not spelled out. My presumption
was that owner_request_special was to allow errors in xxx to go to
xxx-owner or owner-xxx. Silly of me.

It was an issue, of course, because (I've mentioned this a long time ago) I
do fake verp processing with + and = as delimiters, from majordomo, and I
am using address extensions as a way to get those verp fakes back to the
processing scripts, which, for list x is owner-x. I have some convoluted
mail paths, resulting from the fact that I am processing list mail on one
machine using another machine's name. Since it was only the verped bounces
that were bouncing, I guess that a couple folks got a reprieve from being
cycled off the lists.

I guess this was a change since snapshot-19990627, which I'm still running
on my primary majordomo system. That has a owner_request_special parameter
as well, but I'm not sure what it does there. (What did it do? It did not
seem to stop delivery to this address when it was set to yes)

However, I guess I don't understand one thing: I assumed you always try
and match the whole thing, then you would work backwards, no?

So evven if someone had an address of xxx+yyy and this was verped to
xxx+yyy+zzz+qqq, it would try xxx+yyy+zzz+qqq, then xxx+yyy+zzz, then
xxx+yyy, then xxx. So if I have an list-owner alias and I verp that to
list-owner-blech-boy=blech.comscifi.squawk.com, it should eventually find
list-owner if I don't have a longer alias that matches.

I guess my thought is if you use a greedy partial match that it does not
matter what the extension character is. You will find the longest matching
alias (splitting at the extension character) and that is the right thing to
do no matter what. You might have multiple theoretical matches, but you
will match the longest piece.

People who want positive matching will use a different character, say a +,
that does not appear in any of their normal addresses. 

--
Eat natto in the morning and nothing worse will happen to you for the rest of 
the day - http://scifi.squawk.com/natto.html
Nick Simicich mailto:njsscifi.squawk.com
http://scifi.squawk.com/njs.html -- Stop by and Light Up The World!