postfix alias and dovecot quota

[Jiri Bourek]

On 30.6.2014 12:33, Nick Edwards wrote:
> On 6/29/14, Alexandre Ellert <aellert at numeezy.com> wrote:
>> Le 29 juin 2014 à 06:24, Nick Edwards <nick.z.edwards at gmail.com> a écrit :
>>
>>> it is the job of postfix to do this, aliases are just that, aliases of
>>
>>> the real mail account, they do not exist in real storage, else, they
>>> would not be alias.
>>
>> The problem i'm trying to solve is about dovecot capability to serve quota
>> status via Postfix policy server protocol.
>> It works fine when the destination address is a real mailbox, but if it's a
>> Postfix alias, then the email is not rejected because dovecot doesn't know
>> this user.
>> Maybe it's a wrong idea to try to make Postfix alias visible to dovecot.
>>
>> Do you have another suggestion ?
>
> of course its wrong
> mail aliases are for MTA's *only*  its not for dovecot (or any
> pop3/imap server), if postfix is not saying oh ok alias foo really
> goes to user bar, do we;ll check out bar's quota, status etc,, then ur
> postfix is foobarred somehow.
>

I'm not completely sure about that. If you want to use Dovecot's 
quota-status to reject message during SMTP session, Postfix' smtpd 
process needs to do that and - to my knowledge - it's only able to pass 
recipient address, not the aliases involved.

I was looking for a solution to this few months ago as well. In the end 
I created sort of policy service proxy between Postfix and Dovecot. The 
proxy looks up aliases in database, converts them into real users and 
asks Dovecot about those. Final result is then reported back to 
postfix/smtpd.