Envelope rewrite by sendmail?

[Trond Endrestøl]

On Thu, 26 Jan 2017 08:31+0100, Bernt Hansson wrote:

> On 2017-01-25 21:42, Trond Endrestøl wrote:
> > Hi,
> > 
> > I have users with email addresses ending in a long suffix.  Combine
> > this with long names in front of the @ sign, and it immediately gets
> > very tedious to type an email address.
> > 
> > We have a shorter domain name, and I was thinking of creating a small
> > SMTP server to serve this short domain name and simply forward email
> > to the main SMTP server.
> > 
> > It is not possible to switch the main SMTP server to serve the short
> > domain name.
> > 
> > Here's an example:
> > 
> >    A mail messages arrives on the small SMTP server addressed to
> >    shorty at short.tld. Sendmail, though the aliases mechanism, forwards
> >    the message to long.name at some.incredible.long.domain.name.tld.
> > 
> >    Antispam measures such as SPF will flag the small SMTP server as not
> >    allowed to send email on behalf of the originator.
> > 
> >    Thus, prior to forwarding each message, the small SMTP server will
> >    need to masquerade as the originator and rewrite the envelope's from
> >    address to an address within the short.tld domain.
> > 
> > Can this be accomplished using sendmail? Would the short address of
> > the receiver suffice or should I use a fixed address regardless of the
> > originator and/or the ultimate receiver?
> > 
> > The OS on the small SMTP server will be FreeBSD 11.
> > 
> > Any pointers are appreciated.
> > 
> 
> http://www.sendmail.org/~ca/email/doc8.12/cf/m4/masquerading_relaying.html

Thank you for your input.

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