Bug: Shared Mailbox - Case Sensitivity

Leander Schäfer info at netocean.de
Fri Sep 16 12:21:13 UTC 2016

Hi Aki,

Thanks for your advice. Yes, I'm aware of this. Yet lowercasing should 
be the default since Dovecot 2.1.x., isn't it? Yet I wouldn't know where 
exactly to implement this %L, since the ACLs are set through IMAP 
commands through the users mailclient like Thunderbird. So in other 
words, the email address to whom the user want to grant ACLs provided by 
the user's mailclient, has nothing to do with my auth backend where e.g. 
%u => %Lu would apply. PLease correct me if I'm wrong here.

It clearly looks like a bug of the internal processing of the 
"dovecot-acl-list" files. It simply lacks on a lowercase enforcement in 
the code, like it already seems to do for the "dovecot-acl" file.

Best regards

Leander Schäfer

Am 16.09.16 um 12:53 schrieb Aki Tuomi:
> On 16.09.2016 12:54, Leander Schäfer wrote:
>> Hi,
>> unfortunately I found a bug in Dovecot's ACL handling for shared
>> mailboxes. It turns out Dovecot doesn't enforce lower casing the
>> privileged username to whom the mailbox should be shared to. This
>> results in a invalid configuration. Users get confused, since they
>> passed on a valid email address in their ACL setup.
>> /usr/local/www/default/mail/test at mydomain.localdomain/maildir/.Spam/dovecot-acl
>> user=leander at mydomain.localdomain eilrwts
>> ^^ works
>> /usr/local/www/default/mail/leander at mydomain.localdomain/maildir/dovecot-acl
>> user=test at mydomain.localdomain eilrwts
>> ^^ works
>> /usr/local/www/default/mail/test at mydomain.localdomain/maildir/.Drafts/dovecot-acl
>> user=Leander at MyDomain.LocalDomain eilrwts
>> ^^ Doesn't work
>> Best regards
>> Leander Schäfer
> Hi! Did you know you can use %Lu instead of %u to force lowercasing?
> Aki

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