[Dovecot] Shared Mailboxes in a multi domain environment

[Alessio Cecchi]

Hi,

I would like to enable mailbox sharing for my users. I'm using dovecot 
2.1.9 with vpopmail authentication. For security reason shared mailboxes 
should be available only for users of the same domain.

Dovecot's wiki suggest to enable acl like this:

plugin {
   # assumes mailboxes are in /var/mail/%d/%n:
   acl_shared_dict = file:/var/mail/%d/shared-mailboxes.db
}

but in vpopmail, and also in many others configuration, mailboxes are, 
for example, in /var/mail/nas1/%d, /var/mail/nas2/%d and so on, so it's 
difficult to restrict shared mailboxes available only for the same 
domain. A trick could be set acl_shared_dict to 
/var/mail/%d-shared-mailboxes.db, but I don't know if it's safe on an 
NFS environment.

So, why don't provide a way to restrict shared mailboxes also for dict 
in SQL?

One way could be to add to "user_shares" table a column "domains" which 
is the same domain of the mailbox'owner and a config option, for acl, 
like acl_only_for_same_domain =yes/no so dovecot can add a "WHERE %n = 
domain"  for the SELECT.

Are there other possible solutions?
Thanks

-- 
Alessio Cecchi is:
@ ILS -> http://www.linux.it/~alessice/
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Assistenza Sistemi GNU/Linux -> http://www.cecchi.biz/
@ PLUG -> ex-Presidente, adesso senatore a vita, http://www.prato.linux.it