Johannes,
did you double check if your planned setup will not break other things?
Have similar needs but am not yet deep enough into mail to see possible
pitfalls.
Stefan
Am Dienstag, 2. Oktober 2018 schrieb Johannes Bauer :
> Hi list,
>
> I'm having an issue with my Postfix configuration: Currently I've it set
> up so that one authentication SASL login (e.g., m...@foo.com) supports
> multiple virtual email addresses (e.g., m...@foo.com but also
> f...@foo.com, b...@foo.com).
>
> Once authenticated with m...@foo.com, the envelope sender ("MAIL FROM")
> is restricted to only the permissible variants.
>
> However, as I've now painfully found out, when in Thunderbird someone
> uses the "Custom From Address" feature, it doesn't change the envelope
> sender, but only the actual "From" header field. This means, I have the
> following situation:
>
> Auth: m...@foo.com
> Envelope from: m...@foo.com
> Header 'From': anyth...@goes.com
>
> One of my customers used a gmail address in the header "From", sent an
> email to @hotmail.com and now my mailserver is permablocked at Microsoft
> for bad reputation.
>
> How can I ensure in the future that the same checks are applied to the
> Header "From" field that are also applied to the evelope "From" field?
>
> Thanks,
> Johannes
>
