Re: [Exim] How to compare SMTP AUTH login and MAIL FROM stri…

On Thu, 6 Jun 2002, Sebastian Sawicki wrote:

> Hi
> I want do compare AUTH login and Mail From string and reject mail if
> there are different.
> It is possible in exim? How?

Almost surely not in exim 3

If you are using exim 4, this could probably be done within an ACL.

Most implementations of AUTH leave the envelope sender alone, and simple
force-insert a header like "X-SMTP-AUTH: by user@???"

If you are an ISP, keep in mind that it is possible your
authorized/legitimate customers, might have a legitimate need to send
mail 'from' some other mail account(s) they might have.

SMTP AUTH is better used just as an accountability tool, and as a way to
prevent J Random Spammer from relaying through your machine.