On Fri, 8 May 1998, Jeffrey Goldberg wrote:
> For every message that we rewrite a (header) From line for we would like
> to add a (header) Sender line with the original value unless there already
> was a Sender line (which we then won't tamper with).
>
> I actually think that this should be normal behaviour for all From line
> rewriting. I'm I wrong? How can I do this with exim?
For locally-originated messages (i.e. those from the command line
interface or from -bs), Exim throws away any existing Sender: line in
the incoming message, and it adds a Sender: line if the address in the
From: line is not the same as "logged-in-user"@qualify_domain. It does
this after applying any rewriting rules to the From: header. It then
applies the rewriting rules to Sender, if appropriate.
The idea behind this is that if a user tries to masquerade by including
From: Santa@Claus
in a message, Exim will put in the real identity as
Sender: login@domain
but if you are hiding login names by rewriting that will get rewritten
to
Sender: A.User@domain
I am afraid there is no mechanism for adding headers conditional upon
the success of a rewrite. Given that a From: line in principle is
permitted to contain more than one address, doing something like this
could be quite tricky.
--
Philip Hazel University Computing Service,
ph10@??? New Museums Site, Cambridge CB2 3QG,
P.Hazel@??? England. Phone: +44 1223 334714
--
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