Jean-S?bastien Nicaise:
> If a local user sends an email with an invalid email address (mailf
> from:inva...@example.com, for example), the ldap table lookup does not
> return anything, hence the mail is blocked.
>
> If a local user sends an email with a valid email (mail
> from:us...@example.com, for example), the ldap table lookup returns the
> user1's email, then relays the mail.
>
> This works well if the user's email is part of the configured domain (@
> example.com).
>
> The problem is if a user specifies an email address that is not part of the
> configured domain. If the user sends an email with a source address of
> inva...@test.net, for example, the ldap table lookup does not return
> anything, but the email is still relayed.
>
> How could change this behaviour and block this email?
If you can arrange for a database with all the valid addresses on
the internet, then I can show you how to query it with Postfix.
Wietse
