[Dovecot] Posfix and Dovecot (dovecot like LDA) and no space left on the disk

[Andrzej Adam Filip]

On 05/10/2011 08:37 PM, Timo Sirainen wrote:
> On 10.5.2011, at 21.32, Andrzej Adam Filip wrote:
> 
>> Do you intent any time soon to provide some hook to alow MTA reject
>> in reply to "RCPT TO:" (in SMTP session) messages to over quota
>> mailboxes?
> 
> Can you give specifics of what I'd need to do for that?
> I remember there is some sendmail protocol that is also supported by
> Postfix (I think), but I can't remember specifics (and a bit lazy to
> google for it). 
> v2.0 would finally allow easily implementing such
> service. Hmm. I guess such service would both have to check if the
> user exists and also the quota value, and give errors about both of them.

Both sendmail and postfix support milter protocol/API. Unlike API
provided by library the protocol is "not officially" documented.
Sendmail/sendmail.cf could also use trivial "socket map" protocol
(query->response) [sample Perl scripts implementing it are in contrib
directory of sendmail distribution].

IMHO the best honeypot for developers (especially without dovecot
expertise) would be simple library providing two functions
email_address -> state( does_not_exist, under_quota, over_quota)
email_address, message_size -> ( does_not_exist, ....).