Re: [Exim] Resent- headers

Pàgina inicial
Delete this message
Reply to this message
Autor: Phil Pennock
Data:  
A: Exim Users
Assumpte: Re: [Exim] Resent- headers
On 2003-11-11 at 09:35 +0000, Philip Hazel wrote:
> RFC822 and RFC2822 specify that certain header lines must be present.
> Exim makes sure this is the case. IIRC, it is still working to 822,
> which insists on more lines than 2822.


The problem here is that Exim is not fixing up the first set of
header-lines, so as a result is creating erroneous information; the
Resent-Date: stuff in particular is available in Received: trace
headers, but having Exim touch earlier/lower headers is problematic.

> Exim has no built-in concept of "initial submission" or "relay
> submission".


Indeed; but it does have "whilst processing -t", which is a good time to
apply this sort of fix-up; as opposed to general operation.

> > issues at the moment getting a good set of test-cases to figure out when
> > Exim changes which set of Resent- headers, when there are multiple
> > Resent- sets of varying quality.
>
> Multiple Resent- sets (as discussed on a thread some time ago) are a
> total disaster for a number of reasons, not least of which is that there
> is no seriously enforced ordering of header lines. That is why many
> mail-processing programs (MUAs and MTAs) amalgamate multiple Resent-
> sets or rename old ones to X-Resent-xxx when adding new sets.


By my re-reading of the RFC2822 stuff yesterday, if there's a header
line that isn't Resent-*: between Resent-*: then those are separate
instances; what we're seeing is a Resent bounce of a mail which was
already Resent, but that earlier one had erroneously put the Resent
lines at the end of the headers; Exim added lines to that earliest,
lowest point, instead of to the current set, the first group nestled
between Received: headers.

The problem here is _caused_ by a mailing-list manager but Exim's
actions are in effect adding incorrect information -- if it went to the
_first_ set of Resent- headers, and only those, then it would be
correct; the current behaviour isn't correct.

Thanks,
--
2001: Blogging invented. Promises to change the way people bore strangers with
banal anecdotes about their pets. <http://www.thelemon.net/issues/timeline.php>