Phil Howard:
> On Tue, May 25, 2010 at 10:36, Wietse Venema <wie...@porcupine.org> wrote:
>
> > Postfix supports wildcards via regexp/pcre tables.
> >
> > ?1) You can use them for all the tables that define Postfix address
> > ? ?classes: mydestination + aliases, virtual_alias_domains +
> > ? ?virtual_alias_maps, virtual_mailbox_domains + virtual_mailbox_maps,
> > ? ?relay_domains + relay_recipient_maps.
> >
> > ? ?Simply replacing one domain name by another does not produce the
> > ? ?expected result.
>
> That's what I'm afraid of ... particularly if it can result in
> backscatter or open relay. I need to get the test of the valid user
> done at RCPT time, obviously. But the addressed domain could be
> foobar.example.com or xyzzy.example.com or anything else in front of
> the domain, without me knowing what these could be in advance. So I
> can't just have a table of all possible valid u...@hostpart.domain. I
> can have all valid u...@domain even though RCPT can name
> u...@hostpart.domain.
Postfix supports wildcards via regexp/pcre tables:
/^u...@.*\.example\.com$/ will match the user in any subdomain of
example.com.
> > ?2) Postfix 2.7 supports SMTP command rewriting (smtpd_command_filter)
> > ? ?However this would produce an incorrect error message:
> >
> > ? ?RCPT TO:<u...@foo.example.com>
> > ? ? ? ?smtpd_command_filter strips this to ``RCPT TO:<u...@example.com>''
> > ? ? ? ?The Postfix SMTP server then responds with:
> > ? ?550 5.1.1 <u...@example.com> User unknown
In this example, the user really does not exist. Postfix does not
produce an error message when u...@example.com exists.
Wietse
