duplicate suppression, sieve, loops, redirect and lost email

[Ken Murchison]

Quoting Rob Siemborski <rjs3 at andrew.cmu.edu>:

> On Fri, 30 Aug 2002, Ken Murchison wrote:
> 
> > It already does keep track of msgid/rcpt pairs for redirect, but I still
> > don't see how this helps us.  How does the script know that it
> > redirected back to itself?  Perhaps adding the server's hostname to the
> > X-Sieve header would help us determine that this message is coming back
> > to us via a loop.
> 
> I don't think this is good enough, since I could have:
> 
> redirect "leg+cyrus at andrew.cmu.edu"
> 
> in my sieve script, which (if only the server name was included) would
> then get dropped (or bounced or whatever).
> 
> However, putting the expected rcpt-to value in X-Sieve might be
> interesting, since then we have a user and a host name that has already
> seen the message.

Your logic may be correct, but I don't follow.

My thinking is this:

- when we redirect the message, we already store the msgid/rcpt pair in the 
duplicate database

- if/when we see this msgid again, we need to know that it came back to us 
because of a mail loop caused by our redirect

- the only other piece of info that we need is the name of the server (ie, our 
server) that processed this message the first time

- so, if the msgid/rcpt/sieve-server all match, then change the redirect action 
into a keep.

-- 
Kenneth Murchison     Oceana Matrix Ltd.
Software Engineer     21 Princeton Place
716-662-8973 x26      Orchard Park, NY 14127
--PGP Public Key--    http://www.oceana.com/~ken/ksm.pgp