From: Russ Allbery (rra@stanford.edu)
Date: Thu Feb 12 2004 - 15:55:57 CST
Charles Lindsey <chl@clerew.man.ac.uk> writes:
> Russ Allbery <rra@stanford.edu> writes:
>> Then we don't and we make people who are doing complex gatewaying use
>> some other mechanism of loop detection or bypass the normal posting
>> software by using a special interface that allows preservation of
>> Injection-Date (like, say, IHAVE).
> No, we say that they MUST retain whatever Injection-Date header was put
> there the first time it was injected. That was your original suggestion,
> and indeed it stops all loops.
You say "no" but you're agreeing with exactly what I said above. Complex
gateways should use some other interface that allows them to preserve the
Injection-Date header.
Preserving existing Injection-Date headers for regular posting is highly
unwise for all the reasons that we're talking about moving away from using
the Date header. In off-line news reading situations where the person is
running their own local news server, the Injection-Date may be
significantly stale. Likewise for the workaround situations such as the
one that John Stanley described. In those situations, I think the onus is
on the agent doing unusual reinjection to strip the erroneous
Injection-Date before reinjecting the message (an operation that should
require manual configuration and therefore for someone to know what
they're doing).
Please note that people can always create loops if they try hard enough.
Just strip the Message-Id and Date header from a post and repost it. We
can't stop that behavior; we can only put checks in place to keep any
loops from being generated automatically and document exactly how the
detection algorithm works so that people who have special needs can bypass
it when they need to.
-- Russ Allbery (rra@stanford.edu) <http://www.eyrie.org/~eagle/>